In the production of books and products of the book type, more than 30 options for fastening book blocks are used, which can be combined into 14 types and 5 methods (Table 5.1): sewing with threads, sewing with wire, glueless sewing without sewing (KBS), sewing and glue fastening (SCS) and mechanical bonding.

Each method has its own advantages and disadvantages, which determine its predominant use in the production of one or another type of book products and white goods. In the characteristics of each method, financial and labor costs per unit of product are noted, which are discussed in detail in the discipline "Design and calculation of TBPP", as well as the effect of the block fastening operation on the quality of the finished product. Most used by the end of the XX century. in Russia and abroad they have gotten a lot of thread sewing without gauze, wire saddle stitching and glued seamless fastening with spine milling.

Garment sewing with threads without gauze provides high strength, durability and good opening of book products. It can be successfully used in small, medium and large-scale production of books and white goods, since the leading machine-building firms produce a large number of machine tools, automatic machines and units that allow mechanizing and automating most of the bookbinding and binding operations.

Table 5.1

Saddle wire sewing is widely used in the production of small-volume books, school notebooks and various documents due to its simplicity and low labor and material costs. Sewing with a wire, stitching, and especially pocket sewing, find very limited use due to the successful development of adhesive and mechanical fastening methods.

Adhesive seamless bonding methods in the second half of the XX century. They have significantly pushed aside sewing methods for fastening blocks due to the small number of operations and extensive mechanization and automation of production, good disclosure of finished products, but their disadvantage is the high demand for the selection of materials (glue to paper), strict adherence to the modes of the technological process, on which they largely depend strength and reliability of adhesive joints and, consequently, the service life of book products. Sewing and glue fastening combines the advantages of sewing and glue fastening (low labor intensity and high economic indicators, high strength and good opening), but unfortunately, it has not been widely used in Russia and the CIS countries.

Mechanical methods of fastening blocks are mainly used in the so-called tetradless technology, in small- and medium-batch production of white goods and some types of book publications (for example, catalogs of semiconductor devices and other products of rapidly developing industries), since they make it easy to remove individual sheets and supplement block with preprints. Among them, combs and spirals are predominantly used, providing full disclosure of a publication or product, thanks to the mass production of simple and affordable desktop small-sized and easy-to-use equipment for small businesses.

Binding with clips and locks is of limited use in the production of plastic and cardboard folders for storing various archival documents, since it makes it easy to replenish their contents. Two types of permanent fasteners - with screws and rivets - also have limited use: they are mainly used in the production of albums for photographs and stamps (stockbooks).

5.2.1. Block sewing with threads

Block sewing with threads can be performed with a single-thread knotted and double-thread chain stitch (Fig.5.6).

For knotted sewing, the use of long (about 10 cm) stitches is characteristic, their loose tightening and the presence of hanging ends of the thread in the lower part of the block at the knotted knot. This type of sewing is used in foreign practice in the manufacture of small-volume publications in the cover and in the cover, completed with an insert and intended for children of preschool and primary school age. Two or three stitches are usually enough to fasten a block, so the laboriousness of fastening blocks with this type of sewing is not high. In Russia and in the CIS countries, this type of sewing has not found application.

Sewing blocks with a saddle stitch double-thread chain stitch is carried out with special sewing machines of the company "Singer" class 300 model 104, in which the seam is formed by one needle and one hook, which performs the function of a shuttle. The length of the stitches can be adjusted from 6 to 11 mm depending on the block height: shorter stitches are usually used in the manufacture of small-format publications and products (for example, passbooks) in the cover. The De Flores SS / T model (McCain, USA), in which this type of bonding is carried out, allows processing blocks with a format from 78 * 90/32 to 70 * 100/8 up to 5 mm thick at a speed of 60 -70 blocks / min. The production line based on this unit has been successfully operated for a number of years at the Children's Book Production Association (Moscow) in the production of bound cover editions for children of preschool and primary school age.

Block sewing with thread stitch can be carried out with a double-thread chain stitch on sewing machines of "heavy type", for example, class 222 (Podolsk plant, Russia). When implementing this method of bonding blocks, it is recommended to use thin types of printing paper with a surface density of 50-60 g / m2, notebooks - only with side cutting (with a machine direction along the spine) and strong threads of synthetic fibers with a high tensile elongation, linear density in the range of 64-82 tex (g / km) and breaking strength of the order of 15-18 N (1.5-1.8 kgf). In the process of sewing, the thread seam should be 4-5 mm from the edge of the block spine. If these conditions are met, high strength and good opening will be ensured for large and medium-sized book editions.

Sewing with a set-in thread is widely used abroad in the production of school textbooks and other publications for selective reading - encyclopedias, reference books, dictionaries, technological instructions, etc. In Russia, this method is used mainly in the repair of library books.

5.2.2. Loose sewing with threads

When sewing book blocks with thread, each notebook of a completed block is fastened with several (from 3 to 6) stitches, while each stitch fastenes an adjacent notebook in two places with a single and double thread. Loose sewing is carried out on specialized and universal sewing machines. Specialized automatic sewing machines are designed for sewing blocks without gauze with a simple brochure stitch, which is used in the medium and large-scale production of book publications of significant volume, the blocks of which are further processed on automated production lines and units, on which, in the process of processing blocks, the root material provides strong connection of the cover with the block, not sewn on, but glued. Such machines consist of a feeder, a saddle-shaped stationary table with a chain conveyor and push-in rollers, an adhesive apparatus, an oscillating table with mechanisms for piercing needles and gates, a sewing carriage with sewing and needles and hooks, a thread feeder and a receiving table with a push bar.

Universal semiautomatic sewing machines and automatic machines allow you to fasten blocks with two types of sewing on gauze and without gauze using, respectively, simple and adjustable binding and simple and adjustable (or combined) brochure stitches (Fig.5.7).

Binding sewing on gauze is distinguished by the fact that in the process of fastening the block to the spine, a spine material (printing gauze or non-woven material) is sewn, designed for reliable fastening of the binding cover to the block. In this regard, universal sewing machines are equipped with a gauze feeding mechanism and a device for forming gauze loops between the blocks, which is necessary to obtain gauze valves.

When preparing a sewing machine for operation, the feeder magazine is adjusted in height, width and thickness of the notebooks, and its counting and distribution device - according to the number of notebooks in the block. By the height of the notebooks, the position of the nearest leash of the chain conveyor of the stationary table is also adjusted from the push-in rollers that transfer the notebooks to the swinging table of the sewing machine. The glue machine is installed in height so that the glue strip is applied to notebooks with an indent from the spine fold by 1-1.5 mm. Adjustment of the thickness and width of the glue strip in sewing machines is not provided, therefore, their value when gluing the extreme notebooks, which prevents the possible separation of notebooks from the block at subsequent transshipment operations, can only be regulated by changing the composition, concentration and viscosity of the glue.

On the swinging table of the machine, the crimping angle is adjusted to half the thickness of the thickest notebook in the block to ensure the exact position of the stitches on the spine folds of the notebooks of the stitched block. The adjustment of the push bar is also important for the quality of the sewn blocks: the amount of pushing the sewn blocks on the receiving table during the machine operation cycle should be equal to the thickness of simple block notebooks, since only under this condition can the required thread tension and high sewing density be obtained. The movable wall of the receiving table is installed along the height of the sewn blocks with a minimum gap, taking into account the tolerances for folding the notebooks.

When changing the type of sewing and the format of the notebooks, the sewing machine is also readjusted. Sewing tools are installed and fixed in accordance with the required type of sewing and the height of the block, using the preliminary marking of one of the notebooks according to the setting tables. A set of sewing needles and hooks is placed on the sewing carriage and the needle bar, fixing them, respectively, in the holders and in the chucks. The piercing needles and gates (thread guides) are installed on the corresponding strips of the swinging table, with the punctures against each sewing needle and each hook, and the gates - to the right of the hooks at a distance of 9 mm. The mechanism for aligning the notebook before sewing is set to a value greater than the offset of the uppermost stitch from the upper edge of the notebook by 15 mm.

The number of spools of thread should correspond to the type of sewing and the number of stitches, which are set depending on the size and proportion of the paper sheet (Table 5.2). When sewing on gauze, a roll of polygraphic gauze or non-woven material with a width of NS pm:

where V- block height before trimming.

In the process of sewing blocks, the spine material is unwound from the roll as the stitched blocks advance on the receiving table, and the gauze feeder mechanism is adjusted to the amount of formation of a loop of the spine material between the stitched blocks, which is set in accordance with the thickness of the book blocks T b: at T b = 20 mm, the width of the flaps of the root material after cutting the loops on the receiving table of the machine should be 18 mm, and with a greater thickness of the book blocks - 22 mm.

Table 5.2

The duties of the sewing machine operator include preparing the machine for operation: readjusting the sewing machine and feeder in accordance with the type of fastening and the height of the next order block, threading and gauze, filling the glue machine with glue, loading the feeder store, monitoring the quality of sewn blocks, replenishing the sewing apparatus with consumables and a feeder - complete blocks, as well as taking off finished products and placing them on a pallet, in a truck or on a conveyor for sending sewn blocks for subsequent operations. The duties of the operators of semiautomatic sewing machines, which are equipped with small printing enterprises, also include a cape of notebooks on the stationary transport table of the machine, therefore, its high-speed capabilities are not fully used. When manually applying the block notebooks, the machine speed is set within 75-80 cycles / min, but even at such speeds, 20-23% of the time when sewing blocks without gauze and 22- 25% - when sewing on gauze.

In modern sewing machines, the maximum technical operating speed has been significantly increased: up to 115 cycles / min in BNSH-6A and BNSH-6BA machines (Kiev ZPM, Ukraine), up to 140 cycles / min in F145 machines (Stahl, Germany) and up to 300 cycles / min in the FN-Unica model (Kolbus, Germany). In them, there is no setting of sewing machines for sewing with an adjustable brochure stitch, since when using it, the quality of the sewn blocks deteriorates due to a significant (up to 2.5 mm) displacement of every second notebook due to the tension of the threads in the zigzag seam.

Tight gluing when sewing blocks. The presence of a glue machine in sewing machines led to the emergence of a simplified version of the classical technology for processing stitched book blocks, excluding the first four operations: crimping the spine and block, gluing and drying the spine (see Section 6). The use of this version of the technology in the production of multi-volume editions in the cover did not give positive results: the finished books quickly lost their shape and were destroyed during operation. The low quality of books made by simplified block processing is explained by the following: 1) starch glue and glue based on NaCMC do not provide the required strength of the adhesive bond of notebooks; 2) glue strips gluing the notebooks of the block to each other, even with strict adherence to the requirements for preparing the glue machine for work, are located too far from the surface of the spine (the outer edge is at a distance of 1-1.5 mm, and the inner edge is 3-4 times larger) , which leads to the rapid destruction of the adhesive joint, since its inner layers experience the greatest stress when opening the book; 3) strips of glue are uneven and too wide due to the accelerated movement of notebooks when they are pushed from the stationary table of the machine to the swinging table; 4) the position of the glue strip depends on the thickness of the notebooks, therefore, when the glue layer is fixed on the receiving table of the machine, the spine folds of complex notebooks and fractional parts of the sheet turn out to be at different levels with the rest of the simple notebooks of the block.

Patchwork gluing is permissible in the manufacture of low-volume publications and manual covering of blocks with a cover. Technological instructions for TBPP recommend the use of tetrad gluing in cases where publications are printed on coated paper and have swing illustrations in the slots of notebooks.

Materials used for sewing. For casual sewing, sewing harsh nylon threads in three folds of grade 50k (64/3) according to TU 17 RF 5999-73 or matte cotton "special" threads in 6 additions (trade number 30) with a linear density of 68.6 tex (g / km) are used ) according to GOST 6309 with a breaking force of at least 15.5 N (1.58 kgf).

Capron threads are stronger than cotton threads with the same linear density, have a large elongation when stretched, therefore they rarely break off when sewing. In a sewn block, they cause less thickening of the spine, since, with the same strength, they have a lower linear density (grade 50k means: linear density r l= 50 g / km, k - nylon thread).

Polygraphic cotton-polyester gauze NSh (GOST 5196), containing 25% nylon fibers with a rigidity of (19 ± 3) cN (gs), is used as a root material. Instead of gauze, a non-woven material made of synthetic fibers is also used.

For gluing the extreme notebooks of the block during sewing, a 7% aqueous solution of NaKMC with the addition of 4% PVAD is used, and when gluing together, glue based on PVAD with the addition of polyvinyl alcohol and NaKMC is used.

Assessment of the quality of stitched blocks. The quality of the book blocks sewn with thread is assessed according to the following indicators: 1) the presence of the full number of benign notebooks of the given edition, the correctness of their arrangement in the order of the signatures and the absence of inverted notebooks; 2) the correct application of the type of sewing, the number and sizes of stitches; 3) the absence of trims, thread breaks and lowered loops; 4) the absence of displacement in the position of the folds in the spine and along the upper edge from the common plane (tolerance of 1 mm); 5) absence of displacement of punctures from the fold line of notebooks (tolerance 1 mm); 6) the correct position and width of the glue strip on the outer notebooks [the gap of the glue strip from the spine of the notebooks should be (2 ± 1) mm, the width of the strip - (2.5 ± 1) mm]; 7) sewing density. When sewing on gauze, the evenness of the edges and the width of the gauze flaps are also evaluated.

The quality indicators listed in the first three points are assessed visually and by comparison with an approved standard, and dimensional indicators are measured with a metal ruler with a graduation of 1 mm. The sewing density is determined by the foreman of the site or laboratory worker on the PSh device, on which the block attached to the lower notebook is shifted behind the upper notebook by a force of 9.8 N (with a weight of 1 kg), acting in the horizontal direction. The sewing density on this device is judged by the amount of block shift. a, the nominal values ​​of which, depending on the thickness of the block, were given in GOST 20254-74, which was in force until 1981, and repeated in the technological instructions for TBPP. Analysis of these values ​​showed that the average shear values ​​are proportional to the block thickness and can be calculated using the formula

where T b - block thickness, mm. After calculating the value a should be rounded to the nearest 0.5 mm. It is more convenient to present the tolerances for the nominal values ​​of the sewing density in specific figures: with T b = 20 mm D= ± 0.5 mm, at T b = 21-45 mm D= ± 1.0 mm, and at T b> 45 mm D= 1.5 mm.

5.2.3. Factors Affecting the Strength of Loose Thread Sewing

The strength of the thread sewing is determined on a dynamometer with a maximum load of up to 200 N (20 kgf) when tested for pulling out the inner sheets or a whole notebook of the block. The strength of thread sewing depends on the type of sewing, the strength of the paper and the direction of its cutting in notebooks, the volume of notebooks, the strength and relative elongation of the threads, the number and length of stitches, the presence and type of spine material.

From type of sewing the strength of the binding of the notebooks to each other and the strength of the bond of the cover with the block depend. The highest bond strength of the book construction is provided by sewing blocks on gauze binding stitches, in which the gauze is securely connected to the block by zigzag outer stitch elements, and the binding cover in the finished book is fastened to the block by the flaps of the root material. The advantages of gauze binding are used in the production of bound cover editions designed for medium and long life and intensive use. A simple binding stitch is easy to set up, but the arrangement of the stitches in adjacent notebooks one below the other limits the scope of its application to stitching blocks of medium-sized editions due to the large seam of folds (thickening of the spine). When sewing relatively thin blocks, the number of diagonal seam elements fastening the spine material is increased due to the increase in the number of stitches: instead of one adjustable binding stitch, three simple binding stitches can be placed along the block height instead of one adjustable binding stitch. The adjustable binding stitch, which gives half the thickening of the spine when sewing, due to the high strength of binding of both notebooks and a cover with a block, is used in the production of large-format multi-volume publications (with a large block mass) - encyclopedias, dictionaries, reference books, etc.

Sewing without gauze, carried out with the use of simple and combined booklet stitches, provides a very reliable fastening of the block notebooks, allows for complete processing with a block (see Section 6) on automated production lines, but when it is used, the binding of the cover or cover with the block is carried out only by glue, strength and the durability of which depends on many factors (see subsection 1.2.9) and, to a large extent, on the culture of production, quality of raw materials, strict adherence to the formulation of adhesives and modes of the technological process. This type of sewing is widely used in the production of a wide variety of publications of significant volume, designed for medium and long service life with low intensity of use.

The higher tensile strength of paper, the higher is the strength of the sewing bond, but in this test, the direction of its cutting is also of great importance. If the notebooks of a book block have side cutting, then when testing the inner sheets for tearing, the breaking force is directed towards the paper in the transverse direction, in which all types of paper (except for whatman paper of hand production) are always less than in the sideways direction. Of course, this does not mean that in order to increase this indicator, notebooks with transverse cutting of paper should be used, but this factor must be taken into account when drawing up strength standards.

Volume of notebooks practically does not affect the tensile strength indicator of the inner sheets of notebooks, since when the first pair of sheets of the notebook is torn out, the paper is destroyed, and when two or three (or more) pairs of sheets are torn out, the threads are torn. When testing for pulling out of a block of a whole notebook, the strength indicator largely depends on the strength of the sewing and adhesive fastening of the notebook with neighboring notebooks and with the spine material, therefore, with an increase in the number of pages in notebooks, the strength for their tearing increases. In pull-out tests of the first pair of inner sheets of 32-page notebooks, sewn with four stitches, the pull-out force does not exceed 10 N (1 kgf), but when an entire notebook is pulled out, the strength indicator is 12-15 times higher.

Sewing threads blocks, have a breaking force of about 15 N (1.5 kgf), which gives an approximately 1.5-fold safety margin for tearing out the inner sheets of notebooks of medium format book editions, stitched with four stitches. Of course, the more thread strength, the higher is the strength of the sewing binding, but it is advisable to use thicker (higher linear density, lower sales number) and stronger threads only when sewing blocks with a set-in, in which the load on the sewing binding when using a book is much higher. The use of threads made of synthetic fibers that have a large relative extension at break, not only reduces the number of thread breaks in the sewing process, but also contributes to less destruction of the paper block during its machining and when using the book, increases the service life of the publication.

It was found that the bond strength of sheets and notebooks of a book block is proportional to number of stitches, which, as indicated in the table. 5.2, depends on the block height and is justified by the loads that increase when using a book with an increase in the publication format, thickness and weight of the book block. Stitch length has less effect on the strength of the book: doubling the length of the stitches gives an increase in the tensile strength of the sheets by about 20%. Therefore, it is advisable to sew blocks of large format and volume books with the maximum number of short stitches.

According to research carried out at the All-Russian Research Institute of Printing in the 1950s. , the pull-out strength of the blocks, the breaking of the blocks and the bond strength of the binding cover with the block depend on of the kind and the size of the root material. Two types of fabric with a low surface density (cambric and coarse calico) and two types of gauze - shaped and two-thread on the basis were selected as the root material. Studies have shown that the maximum strength of the block is achieved when using double-strand gauze, which has increased tensile strength along the weft and large cells, which provide free penetration of glue to the folds of notebooks when gluing the spine and strong gluing of gauze to the paper of the block and endpapers. Tensile strength, but poorly glue-permeable fabrics showed 21-29% lower strength in block tear tests and notebook pull-out tests.

The bond strength of the binding cover with the block is maximum if the spine material is cut out along the entire height of the block, but when sewing blocks on gauze, this is not feasible, since when cutting the blocks, the edges of the gauze crumble. To prevent the spine material of a smaller size in the block height from entering the finished book on the folding flaps of the cover material of the binding cover, a roll of spine material is cut out with a width less than the nominal block height by 35 mm [see. formula (5.3)]. In the finished book, a strip of gauze should be placed symmetrically, at an equal distance from the upper and lower edges; for this to happen, when preparing the sewing machine for work, the left edge of the gauze cloth is shifted to the upper edge of the block so that this distance in the sewn blocks is 15 mm.

The minimum width of the flaps of the backing material, ensuring their reliable gluing with endpapers, is calculated based on the minimum admissible width of gluing fabric binding materials with paper and cardboard, equal to 10 mm, a 20% margin of safety and the size of the spacing when using thin cardboard for binding covers.

where R m - the minimum size of the distance, mm; kЗп - safety factor of gluing; NS ms - the minimum value of gluing fabric with cardboard, mm.

At R m = 4.5 mm, k zp = 1.2 and NS ms = 10 mm NSμ = 17 mm, which, with a tolerance of 1 mm, is taken into account in the Norms of Consumption of Materials and in the recommendations of technological instructions for TBPP. With an increase in the thickness of the block and the thickness of all materials of the binder cover, the size of the spacing and the width of the flaps of the backing material, respectively, increase to 22 mm.

5.2.4. Sewing blocks with wire

Of the three ways of sewing blocks with a wire (block stitch, block stitch, and tetrad in connector), the most widely used is saddle stitching due to its ease of use, extensive mechanization and automation, the ability in large-scale production to organize continuous flow production at all operations - from block assembly to packaging of finished products. When using it, a minimum of a relatively cheap consumable material is required - a thin wire, it can be successfully used both at small and large printing enterprises, and in small-scale production it requires minimal financial costs for the acquisition of relatively simple and high-performance equipment that requires a minimum of time for readjustment when changing an order. When it is used in medium-scale production, sewing-sewing semiautomatic devices are used, which make it possible to assemble, fasten and cover from 22 to 31 thousand publications per shift, depending on their volume and format.

Modern lining-sewing-cutting machines (HSRA) impress with their capabilities: their maximum technical speed, depending on the needs of production, can be from 8 to 20 thousand copies of finished products per hour. When a stacker and a packing machine are connected to the saddle stitcher, the finished product can be immediately sent to the warehouse or to the customer.

The disadvantage of this method of bonding can be attributed to the fact that it is applicable only when assembling the blocks with a tab, therefore, the volume of publications printed even on thin paper does not exceed 128 pages.

Sewing with a wire stitch it is used relatively rarely - for binding cover editions with a block thickness of 5 to 20 mm, produced in small and medium editions. Its disadvantages include the poor opening of the book and the quick tearing off of the edge sheets at the attachment points when using the book.

Garment sewing with wire on gauze was first carried out in the 1870s. in Germany. The book block sewing machine with wire was designed and patented by Hugo Bremer in 1875/76 and was first demonstrated at the exhibition of the Stock Society of German Booksellers in Leipzig in 1879. It was the first machine to mechanize the very laborious and tedious labor of hand sewing book blocks , which contributed to the rapid spread of this sewing method in Europe and North America. Thread sewing machines began to be produced by the Bremer Brothers company (Germany) 5 years later, from 1884, and these two ways of sewing blocks, semiautomatic machines could no longer compete, and the old-fashioned wire sewing lost its position.

In the 50s and 60s, the lottery sewing of blocks with wire was still widely used in the production of art books printed on highly calendered and coated types of paper, as well as in the manufacture of any other publications intended for export, since sewing is thin (about 0, 5 mm) wire provided "clean" turns of notebooks without flowing into punctures of brown bone glue, which was used in previous years to glue the spine. In the 70s. multi-device semiautomatic wire stitching machines were discontinued, but wire sewing is still used in small-batch production of albums and atlases due to the wide technological capabilities of PSh-4M and 2ShP-4 machines, which make it possible to fasten blocks up to 500 mm in height and up to 125 mm in thickness with four to seven wire staples at speeds up to 65 cycles / min.

Wire block sewing technology. At small printing enterprises, saddle-stitch and set-in wire sewing is performed on single-device wire stitching machines of the MPD type of the State Research and Production Association "Splav" (Tula, Russia) and 4BPSh-30 or on multi-device machines 4BPSh-30/2 (JSC "Kievpoligraph mash ", Ukraine). The MPD machine is designed for sewing blocks up to 14 mm thick, and 4BPSh-30 - up to 19 mm. On multi-device 4BPSh-30/2 machines, from two to four sewing machines can be installed and blocks up to 8 mm thick can be fastened.

When changing the order, the wire sewing machines are readjusted to the type of sewing (saddle stitch or set-in) and to the thickness of the block to be sewn, at the same time the position of the rotary work table is changed, the fixed stop is removed or installed, which fixes the position of the block spine when sewing the set, and the position of the sewing machine is adjusted in accordance with the thickness of the book block. When preparing for the work of the sewing machine, it is necessary to adjust the position of the carriage of the sewing machine, the sewing heads and the flexors of the legs of the staples, and, depending on the thickness of the opened block, the amount of opening of the carriage grips and the gaps between the sewing heads and the folds. The preparation for the work of the saddle stitcher also includes the adjustment of the feeders in accordance with the format and thickness of notebooks and covers, and the cutting section in accordance with the format of the publication.

For fastening book blocks with wire staples, printing wire is used in accordance with GOST 7480 or low-carbon steel for general purpose in accordance with GOST 3282. GOST 7480 provides for the production of 11 types of wire with a diameter of 0.36 to 1.20 mm, of which technological The instructions recommend using only seven: wire with a diameter of 0.4 to 0.7 mm for sewing blocks with a thickness of 0.5 to 5 mm and a diameter of 0.8 mm for larger thicknesses.

With a block height of up to 150 mm, they should be fastened with one staple, with a height of up to 270 mm - with two, and with a higher height - with three staples. When sewing blocks on sewing machines, the position of the staples along the height of the block is not fixed, but this is possible if a cardboard stop (or two stops on both sides) is glued on the table in order to obtain sewing "with transition". In the process of reconfiguring the collating-sewing machine and the saddle stitcher for sewing with one staple, one of its edges should be in the middle of the block height, so that when sewing with a transition (displacement of the staples in the next block by the length of the back of the staple), the staples in every second block are placed symmetrically relative to the middle of the block height. When sewing with two staples, the distance between them should be equal to half the height of the block, and when sewing with three staples, 1/3 of the height. Crossover sewing reduces the likelihood of a stack of stitched blocks and finished items scattering during handling operations, before block trimming and when finished product packaging.

The technology of easy-to-use sewing with a wire. As well as long-term sewing with threads, long-term sewing with a wire in a slot is performed on gauze, the width of the roll of which is determined by the formula (5.3). When reconfiguring multi-device wire stitching machines 2ShP-4 and PSh-4M, the number of sewing machines is set in accordance with the block height: at a block height of up to 210 mm, two machines are installed, at a height of up to 270 mm - three, and at a higher height - four sewing machines. All sewing machines are installed at an equal distance from each other and so that the extreme wire staples are located at a distance of at least 5 mm from the edges of the root material, since otherwise, near the edges of the sparse gauze, the warp threads may shatter and unweave in the process of further processing of the blocks, which will reduce the strength of the sewing bond. The machine is adjusted to one of two possible sewing options: with one or two transitions, displacement of the staples in the adjacent notebooks of the stitched block by a distance slightly greater than the length of the back of the staple, since the thickening of the spine of the block when sewing with wire is 2-2.5 times larger than when sewing with a thread. For sewing with two transitions, the sewing machine is adjusted in cases where the block consists of a large number of relatively thin notebooks: 16-page or larger, but obtained from paper with a low surface density and a large bulk density with a block thickness of more than 10 mm. Sewing 16-page notebooks with a wire with a diameter of 0.4 mm with one transition allows you to reduce the thickness of the spine by 14%, and sewing blocks made up of 32-page notebooks - by 10%; when sewing with two transitions, the reduction in the spine thickness is 19 and 14%, respectively.

In multi-device stitching machines, the size of the staples is not adjustable; sewing machines cut wire blanks with a length of 25 mm, from which staples with a back length of 13 mm are formed. Taking into account the length of the backs of the wire brackets, the distance between them l ms can be determined by the formula

where V- block height before trimming, mm; N n is the number of transitions of staples when sewing; Nс - the number of brackets along the block height; l c - the length of the back of the staple, mm.

For sewing, a wire of minimum thickness (0.36, 0.40 and 0.45 mm) is used, since only half of the thickness of the notebooks is stitched, which does not exceed 0.25 for dictionary paper with an areal density of 50 g / m 2 in 16-page notebooks. mm, and in 32-page notebooks with a maximum paper thickness of 90 microns, it cannot be more than 0.72 mm.

Upon receipt of a new order, the machinist on one of the notebooks makes a marking of the position of the spine material and wire staples (Fig.5.8), and the preparation of the machine begins with the installation of the leftmost sewing machine, by turning the handwheel the overhead table to the extreme right position, after which the right extreme sewing machine set at the extreme left position of the overhead table. Sewing heads of medium (or medium) sewing machines are fixed at an equal distance from the extreme apparatuses and from each other. When sewing blocks with two and three staples, the sewing machines are moved to the right or removed. The wire staple leg folding devices are installed against the sewing heads and adjusted to a gap equal to half the thickness of the sewing books.

The wire of the required thickness starts from the extreme right apparatus. The correctness of the sewing machine setting is checked by sewing one notebook by lifting the overhead table to the extreme upper position. The installation of the gauze roll and the filling of the gauze are performed at the extreme right position of the overhead table. The most important is the operation of adjusting the machine to the sewing density, which is regulated by the amount of lowering of the overhead table for each cycle of the machine. The sewing density adjustment scale is marked with the number of notebooks that can fit in a tightly sewn 25 mm block. In this regard, it is recommended to use a template of the same thickness so that during sewing it is quite objective to set the sewing density of blocks for any thickness of notebooks and paper.

In the process of sewing, the driver manually opens each notebook of the completed block and places it on the overhead table, pushing it against the side and front stops. At the end of sewing of each block on BShP-4M machines, the tape of the spine material is manually cut with a knife; on 2ShP-4 machines, the feeding and cutting of gauze is mechanized. The driver removes the sewn blocks from the overhead table and places them on the work table, as it fills up, interrupting the work on the machine, controls the quality of the sewn blocks, puts them in a pile, refills the gauze valves between the blocks and transfers them to a pallet or to a truck.

The productivity of tetrad sewing blocks with wire on 2ShP-4 machines is 24 thousand notebooks per shift, while the technical utilization factor is 0.769. When working on BShP-4M machines, about 23% of the working time is spent on cutting and filling gauze, so the shift capacity does not exceed 18.5 thousand notebooks.

Quality control of blocks sewn with wire. The blocks sewn with a wire are controlled according to the following indicators: 1) by the number of staples; 2) by the number of transitions of staples when sewing; 3) wire diameter; 4) the distance between the staples; 5) the size of the gauze valves; 6) the correctness of the collation; 7) the absence of displacement of the wire brackets relative to the root fold (tolerance - 1 mm); 8) absence of displacement of notebooks at the upper edge (tolerance - 2 mm); 9) the tightness and length of the legs of the wire staples (the allowable gap between the ends of the legs is 1-5 mm); 10) when sewing on gauze - according to the tightness of the gauze to the spine, the absence of distortions of the gauze, the evenness of the edges of the valves and the correct position of the edges of the gauze in relation to the extreme brackets; 11) the absence of damaged, deformed and contaminated blocks; 12) sewing density.

The control of indicators for the number of staples and transitions, the correctness of the assembly, the tightness of the legs of the staples and gauze, the absence of damage and contamination is carried out visually, and the dimensional indicators for which a tolerance of whole mm is set is carried out using a metal ruler with a scale division of 1 mm. The wire diameter is controlled with a caliper or TIK thickness gauge. The sewing density is measured, as in the case of blocks sewn with threads, on the PSh device (see subsection 5.2.2).

5.2.5. Theory of wire sewing

The work of V.D. Zhmutsky, carried out at MPI-MGUP in the 50s, made it possible to conclude that the process of sewing book blocks proceeds in five stages, characterized by a stepwise increase in the applied load, reaching its maximum and its stepwise fall as the legs of the staple move. in the thickness of the book block. At the first stage, the ends of the legs of the staple are pressed into the block with a smoothly increasing force and mainly compact the upper sheets, bending them at a certain distance, comparable to the diameter of the wire. The greatest compressive stresses in a deformable stack of sheets arise under the ends of the legs of the bracket and especially near the perimeter of the ends due to the concentration of stresses at the edges and tensile stresses in the immediate space. When the resulting compressive, bending and tensile stresses reach the ultimate strength of the paper sheet, a part of the sheet is pulled out along the circumference of the end face of the staple leg.

Since the paper density is uneven near the perimeter of the staple leg end and in the place where the sheets are bent (under the staple end, the air in the pores and capillaries of the paper is compressed, and near the perimeter it is displaced outside of it), stress dissipation is inevitable along the radius of the staple end circumference. As a result, the average diameter of the disk pressed and squeezed out of a sheet of paper (Fig.5.9, a) turns out to be less than the diameter of the wire by an amount approximately equal to the thickness of two sheets of paper in the block.

With further movement into the depth of the block, the leg of the staple compresses the underlying sheets, which are no longer pressured by the end of the leg, but by the torn disc or discs of compressed paper. After pushing through four to seven sheets (depending on the diameter of the wire, thickness and bulk density of the paper), a paper cone is formed under the end of the staple (Fig.5.9, b) with an apex angle of about p / 2 rad (90 °). The second stage is characterized by a constant value of the force required to penetrate the paper cone into the underlying sheets. During this stage, the paper build-up at the end of the leg acts as a cone-shaped wedge, creating high compression stresses by its tip on the next sheet and tensile stresses in several top sheets, as a result of which tears are formed in them mainly along the machine direction of the paper.

The third stage occurs when the leg of the staple with a paper cone pushes the last sheets of the book block (Fig.5.9, v). Since these sheets do not have a solid support under them (since the swinging side strips of the sewing machine are still lowered), when they are pushed through by the staple leg, tearing out of paper particles, the dimensions of which are larger than the area of ​​the end of the leg, are inevitable.

At the fourth stage, the piercing force is sharply reduced, since the movement of the legs is impeded only by the frictional forces of the paper in the punctured holes. At the end of this stage, the back of the staple touches the top sheet of the block and the staple begins to seal the top sheets. In the final, fifth, stage, the legs of the staple are bent, at which the lower sheets experience the greatest compressive stresses near the punctured holes, since only the paper of the block serves as a support for the bent ends of the legs of the staple.

5.2.6. Factors affecting the strength of the wire bonding of blocks

The strength of sewing binding of book blocks with a wire is determined by the force of tearing off a sheet, cover or notebook on a dynamometer equipped with wide jaws for attaching a block, sheet or notebook. The sewing strength indicator depends mainly on the sewing mode and three technological factors - the direction of cutting the paper in the block, the tensile strength of the paper and the number of staples with which the block was sewn or the notebook was sewn to the spine material.

Sewing mode the coefficient of block compaction at the last stage of forming the wire staple in the stitching machine should be considered (see subsection 5.2.5). As shown by the studies carried out at the Department of TP and PP MGUP, the strength of bonding the sheets in the block depends on the accuracy of the sewing machine adjustment to the thickness of half of the notebook when sewing blocks in a saddle-stitch pattern and on the thickness of the block when sewing a set-in. It was found that at the moment of bending the legs of the staple, the position of the pushing bar of the sewing machine in relation to the swinging bars of the mechanism for folding the legs of the staple should exactly correspond to the thickness of the block with the coefficient of compression TO c = 1 [see. formula (3.7)]. Decrease and excess of this indicator by 10% (up to values ​​of 0.9 and 1.1) lead to a loss of strength by 18-21% (Figure 5.10).

Technological factors. When testing for tearing out sheets and when using a book, the forces are directed perpendicularly to the spine line, therefore, from the point of view of strength, transverse cutting of sheets in a block is preferable, since the force in these cases is directed along the machine direction of the paper, along which the strength of the paper is always higher than with force directed perpendicular to it. However, cross-cutting is only permissible when using thin paper in selective reading publications.

The higher the tensile strength of the paper, the higher the strength index; therefore, the highest values ​​of the bond strength are provided by the use of paper No. 1, consisting only of cellulose, without fillers or with a low content of them, with increased values ​​of surface density and thickness. The more staples a block or notebook is sewn together, the higher the strength of their fastening. Numerous tests carried out at the Department of TP and PP MGUP showed that the dependence of the separation force F from the number of staples when sewing N has the form of a straight line outgoing from the origin. In this regard, in the production of publications for children and other publications designed for intensive use, one should not save on wire: sewing with three staples instead of the usual two increases the strength of the binding of the publication by 1.5 times, and the cost of a wire staple is many times lower than the cost of paper and all printing production of brochures or books.

5.2.7. Adhesive seamless bonding of blocks with spine milling

Attempts to simplify the technology of binding book blocks, to replace the old-fashioned sewing with threads by fastening the sheets of the block with glue have been undertaken for a long time. The modern principle of glued seamless bonding (KBS) was proposed in Austria in 1811. In the early 1900s, a significant number of small-format "pocket" editions were issued in a number of countries, the sheets of which were bonded with bone glue with a large addition of glycerin to increase its elasticity, but the strength and the durability of such books left much to be desired. The date of the real birth of KBS can be considered 1936, when the polymerization reaction of vinyl acetate was carried out in Germany and a polyvinyl acetate dispersion (PVAD) was obtained, which ensures high adhesion strength of paper sheets and preservation of the strength properties of the adhesive bond for a long time. In Russia, KBS began to be used since 1948, using foreign equipment purchased in England, and later in Switzerland. In 1955, a hot melt adhesive was obtained in the USA, which has been used for CBS in Europe (Germany, England and France) since 1965, and in Russia and the CIS countries since 1970.

The relatively rapid spread and development of this method of binding book blocks is explained by a number of its advantages: 1) high speed and low labor intensity of the process, which practically do not depend on the volume of the publication, the number of notebooks in the block and the thickness of the block; 2) the possibility of organizing continuous flow production at most of the operations of the technological chain of stitching and binding processes; 3) a significant reduction in financial costs and terms of production of the circulation. The disadvantages of this method of bonding blocks include the dependence of the strength indicators of the KBS on the type of paper used, the correct selection of glue for paper, the need for strict adherence to the technology and processing modes of semi-finished products at all stages of the surface preparation of the spine and the gluing process.

KBS technology using PVAD. In 1998, Müller-Martini (Switzerland) produced Amigo semiautomatic devices with a capacity of 1,500 copies per hour and Tigra automatons for the purpose of gluing without sewing together the blocks of book publications in the cover using "cold" (normal room temperature) glue. , "StarPlus", "Trend-binder" and "Crown" with the maximum technical speed, respectively, 60, 116, 125 and 200-300 cycles / min. On semiautomatic KBS machines, only three operations are performed: 1) spine milling; 2) gluing the spine; 3) covering the block with a cover. Loading the machine after pushing the blocks along the top edge and onto the spine and removing the product is done manually. Natural drying before three-sided pruning after stacking editions with a small foot is carried out on the work table or on the folding truck shelves.

In the large-scale production of cover editions, multifunctional units are used that perform the following operations: 1) pushing blocks; 2) deep milling of the spine; 3) surface milling; 4) cleaning the spine from paper dust; 5) preliminary gluing of the spine; 6) short-term drying; 7) secondary gluing of the spine; 8) covering the block with a cover; 9) short-term high-frequency heating of the radicular zone. Cooling and final drying of the semi-finished products of the publication take place on a long transport, transferring them to the separation of doubles or to three-sided trimming.

For the production of editions in the binding cover, the Kolbus company (Germany) produces three modifications of KBS machines - Raziobinder KM 470, Systembinder KM 490 and Systembin der KM 495 with the maximum technical speed of 100, 166 and 216 cycles / min, and the company "Zigloch" (Germany) - machines SB-3000 and SB-6000 with a maximum technical speed of 100 cycles / min. An important difference between the KM and SB-3000 units is that in the former, the block spine is edged with the spine material of the transverse cutting, and in the SB-3000 unit - by the side cutting material. The KBS machine is included in the production line, which includes a picking machine and a natural drying and cooling conveyor covered with a cover or edged blocks (Figure 5.11).

The operation of pushing the blocks before milling the spine is necessary in order to maintain dimensional accuracy tolerances and the absence of skewing of the spine and upper margins in the finished edition during the BSC; in production lines based on KBS units, it is performed on a vibrating table while transferring blocks from the picking machine to the unit.

In KBS units, the assembled blocks are carried over the actuators using an endless chain conveyor consisting of links with flat clamps, the number of which depends on the number of operations performed, the speed of the unit and the technologically required time for setting and fixing the adhesive layer. Therefore, in different models of Kolbus KM units, the number of links varies from 15 to 39. When preparing the KBS unit for operation, the input of the block spines from the clamps is adjusted in accordance with the thickness of half of the block notebooks and with the tightness of the spine folds. Technological instructions recommend the amount of cutting the spine folds in the milling process to be set taking into account the volume of the notebooks of the block: if the blocks consist of 16-page notebooks, then the size of cutting the folds should be no more than 3.5 mm, and if out of 32-page notebooks - no more than 5 mm (fig.5.12).

These recommendations need to be revised, since they were established for KBS units, which were discontinued shortly after the release of relatively small series; It is also possible that the folding machines and folding machines of the book-magazine rotary printing presses of the 1960s folded notebooks with a very low tightening density of the folds of 3-4.5 mm. But on modern folding equipment, the folding accuracy is significantly increased, so it is too wasteful to transfer 2.5-3% of the paper into chips when milling the spine. Let's explain these numbers with a simple calculation: in 32-page notebooks with the maximum paper thickness d b = 90 microns = 0.09 mm and compression ratio TO c = 0.90 the thickness of half of the notebooks (8 sheets) in the spine will be equal to d k = 8H d b / TO s = 8 × 0.09: 0.90 = = 0.8 mm. With a tolerance of +0.2 mm, 4 mm of "excess" paper is milled, which with a block width of 135 mm (for the most common format 84ґ108 / 32) is (4: 135) × 100% = 3%.

The purpose of the first deep milling is to remove all the spine folds of the block, including the folds of the inner lobes of the notebooks. On KBS units, this operation is performed sequentially by two milling cutters at different milling depths in order to reduce the likelihood of tearing out large paper particles. With repeated milling, a kind of cleaning of the rough rough surface obtained during the first milling is performed, large tears in the paper are eliminated, and the average depth of irregularities decreases. This is achieved due to a significantly (5-10 times) shallower milling depth and the use of various abrasive materials glued to metal discs instead of cutters.

Paper dust closes the micropores and mouths of the paper capillaries, making it difficult to wet and stick in the subsequent operations of gluing the spine, therefore, dust removal with rotating brushes and suction greatly contributes not only to improving working conditions, but also to obtaining a reliable adhesive seam of the adhesive joint.

It is recommended that the primary gluing be done with a relatively thin layer of glue of low concentration and viscosity, since its purpose, as in the previous operation, is to create conditions for wetting the surface and deep absorption of a relatively low-viscosity and more liquid layer of glue compared to the second, main, layer of glue. The primary gluing of the spine is performed with a low-viscosity undiluted or diluted to 45% dry residue polyvinyl acetate dispersion (PVAD) with a nominal viscosity of 45-60 s according to the IUD viscometer. A short-term irradiation with quartz infrared lamps, intermediate between two gluing of the spine, can only be conditionally called drying, since its main purpose is to create a temperature gradient (see Section 1.3.5), under the influence of which the moisture of the glue first rushes into the depth of the block, and after being covered with a cover or the edging of the block with spine material _ and to the spine surface.

The purpose of the secondary gluing of the spine is to create a relatively thick and durable film, therefore, in this operation, undiluted PVAD with a relative viscosity of 60-80 s according to the IUD viscometer is used, which ensures high cohesive strength of the adhesive bond and the required durability of the publication. After covering with a cover or gluing the spine material (and on SB-3000 and SB-6000 units from Zigloch - after edging the spine), the spine zone is subjected to high-frequency heating in order to quickly remove moisture from the adhesive layer and spine zone of the book block in the course of its further natural drying on a conveyor belt and on pallets or in wagons before three-sided cutting.

KBS technology using hot melt glue. In this version of CBS with spine milling, hot melt glue is used, which includes a vinyl acetate copolymer and various additives that increase elasticity, stickiness, reduce the melting temperature range and slow down the aging process. For example, in the composition of the domestic hot melt adhesive TK-2P, the main component is a copolymer of vinyl acetate with ethylene, the plasticizing additive and reducing the melting temperature range is paraffin, and the tackifier is rosin pentaerythritol ether. The density and working temperature of hot melt adhesives depend on the composition and quantitative ratio of the main components in it (since the amount of aging retarders does not exceed 2%). For most formulations, the density of hot melt adhesives is approximately 0.95 g / cm 3, and the operating temperature range is in the range of 140-180 ° C. In practice, it is preferable to use hot melt adhesives with a lower operating temperature range, of the order of 140-160 ° C, since at its large values ​​not only the curing time of the adhesive layer increases, but also the process of thermal destruction of the copolymer in the finished product is accelerated.

When preparing the KBS unit for work, the gaps between the clamps of the chain conveyor and the cutters of the cutters are carefully adjusted, since the quality of the surface preparation of the spine depends on this. During the first milling, 60 to 80% of the part of the spine protruding from the clamps is spherical. This value depends mainly on the indicators that determine the tensile strength of the block paper: on the surface density, bulk density, degree of gluing and direction of cutting. If the tensile strength of the paper is low, 60-70% of the part of the spine protruding from the clamps should be removed, since at a higher value of this indicator, large tears of the paper are possible, which cannot be removed during the subsequent processing of the spine with a second cutter and abrasive materials.

When fastening blocks of publications designed for intensive use, in order to increase the strength of the CBS, narrow transverse grooves are cut out with a special cutter along the entire height of the spine of the blocks. The width, height and pitch (distance between adjacent grooves) are set in accordance with the degree of gluing, composition (number) and type of paper finish, since these indicators determine the completeness of wetting and the depth of penetration of the glue into the pores of the paper. The width of the grooves can vary from 0.3 to 0.5 mm, the depth - from 0.5 to 1.0 mm, and the pitch - from 4 to 8 mm. If the blocks consist of weakly glued paper No. 2 containing wood pulp, then use a cutter with cutters 0.3 and 0.4 mm thick, the depth of the grooves is set within 0.5-0.6 mm, and the step between them is 6-8 mm. When milling the spine of blocks consisting of glued and highly glued, calendered and highly calendered paper with a smoothness of more than 120 s, containing only cellulose, the groove width is increased to 0.5 mm, the depth to 0.8-1.0 mm, and the pitch is reduced to 4-6 mm.

The gaps between the milled spine and two to four rollers of two glue machines of machines and units of the KBS are set in a certain order and by the amount specified in the instruction manual for the equipment. In most machines, as the milled block moves to the cover section or gluing the backing material, the gap increases from 0.1-0.5 to 0.5-1.5 mm, and the excess glue is removed with a scraper or a rotating brush and a counter-rotation roller. The increased gaps between the glue rollers and the spine surface reduce the dynamic load when the glue comes into contact with the paper and the likelihood of excessive penetration between the sheets of the block. The thickness of the glue layer on the spine and the consumption of hot melt glue are regulated by setting a gap between the milled surface of the spine and a counter-rotation roller or a scraper that removes excess glue. The size of the gap is recommended to be set within 0.4-1.0 mm, depending on the thickness of the block T b and (in the manufacture of cover publications) from the surface density of the printing and cover paper. At T b £ 10 mm adhesive layer thickness d to should be d k = (0.5 ± 0.1) mm; at T b £ 20 mm d k = (0.65 ± 0.15) mm and at T b> 20 mm d k = (0.8 ± 0.2) mm.

When using printing paper with a basis weight of more than 70 g / m 2 and burning paper with a weight of more than 120 g / m 2, the thickness of the adhesive layer should be increased towards the positive tolerance.

KBS options with spine milling. In the 50s, the Ukrainian Research Institute for Special Types of Printing developed a version of the KBS with milling and reinforcement of the spine. A distinctive feature of this option is that after milling, transverse cuts are made on the spine, into which, after gluing the gauze, this spine material is pressed in, connects the sheets of the block with threads, increasing the strength of the sheets bonding in the finished book. To implement this method, the Kharkiv ZPM produced semiautomatic sewing machines PBS, in which processing is carried out by screwing blocks placed in containers. When loading containers, plates are placed between the blocks, forming gauze valves and allowing artificial drying of the roots of the blocks in a clamped state. The increased strength of the KBS with the reinforcement of the spine made it possible to use this method of fastening the blocks for publications in a binding cover, designed for an average service life and intensive use, for example, in the production of school textbooks.

In units of the 650 type series (factory LBV, now the firm "Stahl-Bremer", Germany), designed for sewing-glue and glue-free fastening of blocks with a share edging of the spine, the spine is glued sequentially by three rollers, the first two of which are tapered, turned cut off tops in different directions. When the blocks move over the tapered rollers, notebooks and sheets in notebooks are fan-shaped alternately in both directions, as a result of which the spine edges of notebooks and their sheets move relative to each other, providing glue access to the side surfaces of the sheets. It is argued that with such a smear, the glue penetrates deeply into the spine and the sheets or notebooks are not only held in the spine by the adhesive film, but also stick together.

This version of the KBS with spine milling is not widespread for the following reasons: 1) the uncut upper folds of the block notebooks interfere with the uniform bending of the sheets; 2) the distance from the clamps of the conveyor to the surface of the glue rollers is not the same, depends on the thickness of the block and the serial number of the notebooks in the block, as a result of which the bending radius and the relative shift of notebooks and sheets along the block thickness are different (Fig.5.13);

3) notebooks and sheets of the block, oriented towards the apex of the cone, can deflect under negligible loads from the side of a thick layer of concentrated high-viscosity glue; 4) the sheets of each notebook, adjoining the edges with the surface of the tapered roller, also fan out from the top to the front edge of the block. All this leads to uneven spreading of the root zone of the blocks and a decrease in the quality of their adhesive bonding.

5.2.8. Adhesive seamless bonding of blocks with partial destruction of folds

The purpose of sewing-free methods with partial destruction of folds is to preserve part of the spine folds, since paper, as a rule, is stronger than a glue bond, and to use the advantages of notebook technology in terms of printing a publication on full-format sheets, processes for making notebooks and book blocks. These goals are achieved in three essentially similar ways: by perforating the root folds, milling out several small zones (slots) and milling the middle part of the spine (Fig. 5.14).

In all three versions of the KBS with perforation of the folds and milling of a part of the spine of the block, from 60 to 80% of the spine folds are destroyed, which, when gluing the spine, allows you to fasten the notebooks to each other, ensure the penetration of glue inside and glue the inner lobes of the notebooks. These methods allow the use of only 16- and 8-page notebooks, since when using 32-page notebooks, weak tightening of their folds requires too large a milling depth, which makes it difficult for glue to penetrate the inner lobes of the block notebooks, significantly deteriorates the opening and decreases the strength of the editions or products.

The most simple is the KBS technology with root fold perforation, which can be performed on almost any folding machine (see subsections 2.4.3 and 3.3.1). Milling of the splines and the middle part of the spine can be performed individually or by screwing with one or several cutters on special machines, since the movement of the block and the cutter relative to each other usually occurs perpendicular to the line of the block spine. The milling depth of blocks assembled from thin notebooks does not exceed 1.0-1.5 mm. For gluing the spine, a low-viscosity 33-40% PVAD is used, which ensures good wetting and deep penetration of the glue into the slots, between the folds of the notebooks and between the milled sheets. To increase the strength and durability of publications and products in the cover, the milled part of the spine is glued with a non-woven material or a thin cloth. In the manufacture of book products in the binding cover, the block is edged with the spine material coming into the endpapers.

The version of the KBS with perforation of the spine folds is used abroad in the manufacture of white goods, small-format and low-volume magazines, publications of fiction with an average service life. Variants of KBS with milling of slots and the middle part of the spine are used in the production of multi-volume editions of fiction, catalogs, albums for stamps, etc.

5.2.9. Adhesive seamless bonding of blocks without destroying the spine folds

The idea of ​​using in notebook technology for glue binding of block sheets without destroying the spine folds of notebooks has long attracted printers-technologists for its advantages: this option does not require the operation of milling the spine and transfer of about 3% of the paper into shavings, it allows you to get spreads of the book publication that are not damaged by sewing tools and materials, which are very convenient and desirable when reproducing paintings and maps. Back in the middle of the XX century. MV Balandin proposed an option for obtaining 16-page notebooks of four-fold combined folding (Fig. 5.15), in which four single-fold leaf lobes are located with the roots in one direction. This variant could not be used commercially, since folding machines did not allow producing such notebooks with the required accuracy of alignment of all four root folds. Other methods involve the application of wide or narrow strips of liquid glue or hot melt glue to the places of the intended folds in the press - after printing or (in roll-fed rotary presses) and during the folding process.

Method of single-fold notebooks. This method in relation to the production of geographic atlases was developed at the All-Russian Research Institute of Polygraphy and was used for some time in cartographic publishing. Navigational charts used in sea and river voyages are printed on highly glued, thick and rigid cartographic paper, the bond strength of which with PVAD glue is insufficient, therefore, in this version of the KBS, an alcohol-water solution of methylolpolyamide resin was used, which, when applied twice with short-term intermediate drying, provides high strength and excellent frost resistance bone adhesive joints.

The method of fastening two- and three-fold notebooks in the root folds with narrow (up to 4 mm) strips of liquid "cold" glue in the middle of the root margins was implemented using systems of jet glue devices of the "Optimatic 6000" type ("Planatolwerke" company, Germany), which can be equipped with book-magazine roll-to-roll folding machines. Inkjet glue machines allow you to apply glue to a folded paper tape in a continuous or broken line of various widths, taking into account the absorbency of the paper and the volume of notebooks. In the simplest version of the edition of 16 and 32 pages (with 3-fold combined folding with collapse), printed and glued on such machines, only need cutting and packing operations. Processing of multi-volume editions in the cover and in the binding cover is performed on any KBS machines when the spine milling section is turned off.

The method of binding notebooks along the spine folds using hot glue was developed in the laboratory of TBPP VNII Polygraphy. The method involves applying hot glue strips with a width of about 9 mm to the spine field in a special section of sheet-fed printing machines. The bonding process itself can be carried out in KBS machines when melting hot glue strips in the high-frequency heating section of the spine zone of book blocks.

A version of the KBS with preliminary application of strips of "cold" polyamide glue with a width of 6 to 10 mm to the middle of the root margins in roll-to-roll printing machines was developed at the Department of TBPP (now technology of printing and post-printing processes) of MGUP. The glue dries up as the paper web moves towards the folder. Heat-sealing of notebook sheets at the place of the root folds to a width of not more than 0.5 mm occurs until the root fold of the notebooks is obtained. The relatively wide glue strips strengthen the paper in the spine area and ensure that all sheets are heat sealed, taking into account the tolerances for print register accuracy and folding accuracy. The small width of the heat seal ensures good opening of the book publication, and the use of polyamide glue ensures frost resistance down to -50 ° C. This version of the KBS allows you to eliminate the skew of the margins in the finished books, which inevitably occurs in all versions of the KBS with spine milling due to the weak tightening of the spine folds in notebooks.

Both versions of CBS with heat sealing of a pre-applied adhesive layer have not received industrial application.

5.2.10. Assessment of the quality of blocks fastened by the BSC

When setting up the KBS machine and during its operation, the main attention is paid to the quality of the surface preparation of the spine during the milling process, the thickness of the applied adhesive layer and the strength of the adhesive bond. The quality of the surface preparation of the spine is assessed visually by comparison with a reference block made of the same paper, or, in doubtful cases, by measuring the average depth of macro unevenness of the sheet taken from the middle of the milled block. Technological instructions recommend measuring the depth of macroroughnesses at 10 points along the entire height of the root with an interval of 15-20 mm and calculating their average value h cf, which with good milling quality should be in the range of 0.25-0.40 mm. Measurements are performed with a reference microscope MPB-2 with a scale division of 0.05 mm.

Assessment method described above h c needs revision, since it does not meet the requirements of GOST 2789 and the international standard for assessing the surface roughness of printing paper. The methodology of technological instructions, in fact, proposes to make a random sample of a controlled quality indicator, the volume of which, in order for it to be representative, must be at least 25 copies (in this case, measurements). GOST 2789 recommends measuring irregularities in a row, that is, making an instant sample, in which the number of measurements of the controlled parameter can be reduced by an order of magnitude (maximum - up to three).

Analysis of the macrogeometry of the milled surface of the spine of the blocks showed that the degree of its development (and this is the goal of milling the spine in CBS) is determined not so much by the depth of macroroughnesses as by their number along the spine height and the shape of the grooves or tops; for example, a symmetrical shape gives the smallest increase in root surface. To take into account the degree of surface development, the author proposed to introduce the coefficient of macroroughness steepness into the assessment of the quality of milling the spine of blocks TO to as the ratio of the sum of the depths of irregularities to the base length (Fig.5.16):

where h i- uneven depth, mm; N- number of grooves measured; l- base length (distance between the left edge of the first and right edge i-th irregularities), mm.
The number of measurements of instant sampling can be reduced to 5, but if there is a significant difference in the quality of milling along the height of the blocks, then measurements should be made in three places (in the middle and along the edges of the sheet), and the calculation h from the total sample - according to the results of 15 measurements.

The thickness of the applied hot melt glue film can be estimated with a measuring magnifier LI-3 (GOST 8309) with a graduation of 0.1 mm. When using PVAD, the border between the paper surface and the adhesive film is not visible, therefore the glue is tinted with an aqueous solution of auramine or chrysopheline dyes at the rate of 20-30 ml of a 3% solution per 10 liters of glue.

The strength of the KBS under laboratory conditions is measured on a dynamometer with a breaking force of at least 30 daN (kgf). Three sheets of the block are tested: two 15s from the beginning and from the end and one from the middle of the block. The strength of the CBS is estimated by the specific pull-out force f, kN / m (kgf / cm), which is calculated by the formula

where F i- values ​​of the force of tearing out of sheets, daN (kgf); N and is the number of pull-out tests; V- block height before trimming, mm.

According to the standards developed by the Institute "Adhesive Products" (USA), the strength of the BSC is assessed using a four-point system (Table 5.3).

Table 5.3

The blocks fastened and edged or covered with covers should not have splits (violations of the integrity of the adhesive joints of the sheets), but gaps between sheets up to 0.2 mm wide are allowed, which are formed when the blocks are lowered from the clamps of the KBS machine before gluing the spine and subsequent operations. The penetration depth of the glue between the sheets of the block should not exceed 1.5 mm, but individual streaks up to 3 mm are allowed. When covering blocks with a cover with a gap, the width of the glue strips on the spine margins of the blocks should be equal to (5 ± 2) mm. Dimensional indicators over 2 mm are controlled by a metal measuring ruler or tape measure with a stop that fixes the reference point.

The quality of the products of the KBS machines should be monitored no earlier than 1 hour when the blocks are bonded with hot melt glue and no earlier than 3 hours when they are bonded with "cold" adhesives. When using express control methods, it is possible to significantly improve the quality of products due to a timely change in processing modes, if the dependence of the strength of the CBS on the time of natural drying or cooling in the first hours of the formation of an adhesive bond of the block sheets is known.

5.2.11. Factors Influencing the Strength and Durability of CBS with Spine Milling

In the 60s and 70s. The department TBPP MGUP carried out research work, which made it possible to establish the influence of numerous factors on the quality of book publications, fastened by the most common type of KBS with milling of the spine of book blocks. These studies formed the basis of technological instructions for the production of cover editions on machines "Jet-Binder", "Rotor-Binder RV-5" and others (firm "Müller-Martini", Switzerland), which were equipped with many large printing houses in Russia and CIS countries. It was found that the spine milling modes and a number of technological factors associated with the physicomechanical and physicochemical properties of paper and glue have a significant effect on the quality of the surface preparation of the spine and the strength of the CBS of book blocks.

Milling modes. Milling modes include the amount of root exit from the clamps, the size of the gap between the clamps of the block and the teeth of the cutter, the feed rate of blocks to the cutter and the sharpness of the cutters. The quality of the mechanical processing of the root is characterized by the macro- and microgeometry of its surface obtained after milling: the size of the contact area of ​​the adhesive layer with the paper, and at the molecular level, by the number of active centers per unit area of ​​the rough surface of the root. Since the fibrous structure of the paper does not allow even an approximate determination of the true development of the surface when milling the spine, the average depth of macroroughness is considered to be an indicator of the milling quality (see subsection 5.2.10 and Fig. 5.16).

The amount of the spine coming out of the clamp. As mentioned above (see subsection 5.2.7), when milling the spine of the blocks, it is necessary to remove from 3.5 to 5 mm of the width of the spine zone. But when milling only 2-3 mm of the spine width, the depth of macro unevenness can exceed the permissible value of 0.4 mm, therefore, with the notebook technology, a large spine exit from the clamps is milled in at least two steps, so that during "finishing" milling the spine exit from the clamp does not exceed 1.5 mm.

The size of the gap between the clamps and the teeth of the cutter. An increase in the gap between the clamps and the teeth of the cutter from the minimum (0.5 mm) to 1 mm, by only 0.5 mm, increases the depth of macro unevenness by about 1.4-1.5 times, which in many cases leads to an unsatisfactory state of the milled surface and low quality KBS. The size of the gap should always be set to the minimum, which is allowed by the quality of the cutter and the technical condition of the machine.

Milling speed. With an increase in milling speed, the average depth of roughness increases linearly, and the initial depth of roughness at the minimum speed of the machine depends on the size of the set gap between the block clamps and the cutter teeth and on the position of the sheets in the block (Fig. 5.17 and 5.19). With an eightfold increase in the feed rate of blocks to the cutter (from 7 to 56 m / min), the depth of macro unevenness in the middle of the block increases by about 12%, and at the entrance and exit of the block - by about 1.5 times; the strength of the KBS decreases by about 25% (Fig. 5.18).

Sharpness of the teeth of the cutter. As the cutter becomes blunt, the average depth of macroroughnesses increases, and to the greatest extent - in the second half of the block, and especially when the block comes out of the cutter (Fig. 5.19). This circumstance requires constant attention from the driver and regular checking of the milling quality by comparing the controlled blocks with a reference sample.

Technological factors. The quality of book blocks after spine milling largely depends on the stiffness of the block paper and the resistance to bending of the spine zone protruding from the clamps of the main conveyor of the KBS machine during milling. The value of these parameters depends on the thickness of the block and the thickness of its constituent notebooks and sheets of paper, its composition, bulk mass (density), degree of gluing, thickness and direction of cutting. Another group of factors is the concentration, viscosity, temperature and thickness of the adhesive layer or the consumption of adhesive per unit of root surface.

The thickness of the block, notebooks and paper. The resistance of the block spine to bending is the smallest in the extreme notebooks and sheets of the block, since when the block is secured with the clamps of the main conveyor of the KBS machine, they are fan-shaped and move away relative to the middle of the block. Therefore, at the first moment of the forceful action of the teeth of the cutter on the spine of the block, the outer sheets do not have support against the sheets of the middle part of the block. The last sheets of the block are in an even more disadvantageous position, since at the exit of the block from the cutter, the teeth of the cutter squeeze the sheets from the middle of the block even more, the air gaps between them increase, and the bending resistance of the remaining sheets decreases. For these reasons, the average depth of macroroughness turns out to be minimum in the middle of the block and maximum at the edges (see Fig. 5.19).

Paper composition... The fiber composition of the paper significantly affects the quality of the surface preparation of the block spine and the strength of the CBS. The influence of this factor is not unambiguous: paper No. 1, which does not contain wood pulp, provides a smoother structure of the milled surface, stronger adhesion of cellulose fibers to each other, but a relatively high bulk density (density) and lower porosity make it difficult for high-viscosity glue to penetrate into its capillaries and pores ... The greatest strength of CBS is provided by paper No. 2, which contains a moderate amount of wood pulp, which increases the porosity and absorbency of the paper. The high strength of the CBS is also ensured by fine-pored gravure printing paper made of high-quality fibrous material containing a significant amount (up to 22%) of finely dispersed filler.

Bulk weight. Bulk density (density) of paper, if it does not contain a large amount of fillers, characterizes its porosity and, consequently, absorbency. Therefore, as a rule, all types of paper with a relatively low bulk density (machine smoothness), in comparison with calendered and highly calendered, provide a higher strength of CBS.

The degree of gluing. The high degree of gluing of offset and especially cartographic paper has a negative effect on the strength of the CBS, since the rosin esters used for gluing domestic paper impart hydrophobicity to it, impairing the wetting of paper with water-based adhesives. The use of glued and high-glued paper leads to a significant decrease in the strength of the CBS, therefore, when using this method of bonding in publications printed with an offset method, other parameters of the paper that determine its stiffness are limited. The greatest strength and stability of the results with KBS is provided by low-glued letterpress paper No. 2.

The thickness of the paper. When glued without seam binding, the best indicators of strength and durability of books are provided by thin types of paper - up to 90 microns thick and areal density up to 70 g / m 2. Thicker types of paper, due to their high rigidity, have a significant force effect on the adhesive bonding of sheets in the spine when using a book, leading to its rapid destruction; for KBS books designed for a long service life or intensive use, they are unsuitable. The use of offset paper with a surface density of 80, 100 g / m 2 and above is possible only under the condition of fractional cutting for publications designed for short and medium service life and low intensity of use.

Cutting direction. Fractional cutting of block paper provides the least force effect on the adhesive bonding of sheets when using a book, but in the process of milling, especially with a blunt cutter, tears are often formed in fractional cutting paper outside the macro unevenness, which sharply reduces the life of a book publication. It should also be taken into account (when selecting the concentration, viscosity and consumption of glue) that with side cutting, the average depth of macroroughnesses and their number along the block height are always less than with cross cutting. Cross-cutting of sheets of a block is permissible and recommended by technological instructions when using thin and low-strength types of paper, since in such cases the durability of publications is decisively influenced by the tensile strength of the paper and the degree of development of the spine surface during milling.

Concentration and viscosity of the adhesive. On KBS machines with a one-time gluing of the block spine, undiluted medium- or high-viscosity PVAD grades DF 51/15 VP, DF 50 / 7.5 VP, etc. are used. with a dry matter content of 50 to 55% and a relative viscosity of 41 to 100 s according to the IUD viscometer. This dispersion provides a high cohesive strength of the adhesive layer, but its adhesion strength to the glued paper of the block may not be sufficient. In KBS machines with double gluing of the root, the first gluing is performed with a low-viscosity dispersion with a relative viscosity of 18 to 35 s, and after intermediate drying - medium and high-viscosity PVAD with a relative viscosity of 32 to 75 s according to the IUD viscometer. Double gluing of the spine allows to obtain high adhesive and cohesive strength of the glued joint of the block sheets.

Adhesive film thickness and adhesive consumption. With an increase in the thickness of the adhesive film to a certain limit, the strength of the adhesive seamless bonding first increases and then decreases (Fig. 5.20).

The figure clearly shows that the maximum strength of the CBS occurs at a flow rate of 50% PVAD equal to 800 g / m 2. Simple calculations show that the average thickness of the adhesive layer is 0.736 mm, since the density of polyvinyl acetate r PVA = 1.19 g / cm 3, 1 kg of 50% PVAD has a volume V= 920.17 cm 3 and density r 50 = 1.087 g / cm 3. In any volume of 50% PVAD, the dispersion medium occupies 54.34%, and polyvinyl acetate - 45.66% of the glue volume. During film formation in the process of absorption and evaporation of the dispersion medium, it must be removed in an amount from 6.7 to 28.4% in order to form, respectively, cubic and hexagonal packing of the solid phase of the adhesive.

At a consumption of 800 g / m 2 of glue and with cubic laying, polyvinyl acetate creates an air-dry film with a thickness of 0.687 mm, with a hexagonal one - 0.527 mm, with an equiprobable one - 0.607 mm. In a dry glue film, a combined version of PVA laying is most likely, therefore, its thickness will be approximately equal to 0.6 mm. If the average depth

Macroroughness is 0.4 mm, and the areas of the grooves and tops are the same, then only 1/3 of the total amount of glue, about 0.2 mm of dry film, is spent on the complete filling of the macro-grooves. In this case, 0.4 mm of air-dry glue should remain on the surface of the spine. If, when assessing the quality of the BSC, the thickness of the adhesive film on the spine turns out to be less than this value, then this means that the PVAD consumption is less than 0.8 kg / m 2, or the penetration depth of the glue between the sheets of the block is greater than the maximum permissible value of the average depth of macroroughnesses.

PVAD temperature. The greatest strength of CBS is ensured if at the time of application the glue and paper have a temperature of (20 ± 2) ° C. With a decrease in the glue temperature to 10 ° C, the strength of CBS blocks fastened with polyvinyl acetate dispersions from various manufacturers decreases by 1.1-1.4 times, but the greatest drop in strength is observed with an increase in the PVAD temperature to 30 ° C - by 1.5 -1.8 times, while the decrease is the greater, the lower the initial viscosity of the dispersion.

5.2.12. Sewing and glue binding of book blocks

The sewing-glue method for fastening book blocks was developed at the TWT plant (Stahl-Bremer, Germany) in the 70s. According to this technology, the binding of book blocks is carried out in two stages: first, the sheets of notebooks are fastened with thread staples in the process of folding the notebooks, after which, during the processing of the completed block, the stitched notebooks are fastened with glue and edged with some kind of spine material.

For sewing notebooks, complex two-component (for example, viscose-polypropylene) threads are used, one of which serves as a kind of hot glue during sewing. In the process of sewing, the sewing machine forms a thread staple, pierces two holes in the spine field of the open notebook with thin needles and pushes the legs of the thread staple into them. The bending and attachment of the legs is carried out with tools heated to about 250 ° C, which melt the fusible component of the thermal thread and press the legs of the staple to the outside of the notebook. The fastening of the legs of the staples to the paper occurs due to the natural cooling of the melt during the movement of the semi-finished product to the operation of the last root fold.

In the original version, sewing of notebooks with thermal threads was carried out with one to four sewing machines model 311, fastening each notebook with 2-8 staples, depending on the height of the spine. The devices were installed above the last transport table of the folding machines serially produced by the TWT plant. Since 1983, a model 341 sewing and folding machine has been put into production, which can be connected to folding machines of any manufacturer. The machine 341 implements the rotary principle of sewing with thermal threads in time with the operation of the folding machine; the length of the backs of the staples with which each notebook is sewn is constant, and their number depends on the height of the spine. In small-scale production, sewing of exercise books with thermal threads is performed on model 301 sewing machines, when working on which the exercise books are placed manually on a horizontal table under the sewing machine, and the sewing machine is turned on by pressing the pedal.

Glue binding of notebooks and subsequent operations (edging and high-frequency heating of the spine zone) are performed on specialized semiautomatic machines of the SB-3000 type or on universal machines SB-6000 (Zigloch, Germany), which provide for fractional edging of the block with spine material. This version of the edging, in comparison with gluing the spine material of the cross cut, makes the block more compact and durable, since the flaps of the edging material attract the outer notebooks of the block to the neighboring ones, ensuring their more reliable gluing to the block.

Sewing and glue binding of the blocks allows to obtain very high strength and durability of book editions in the binding cover, which, in terms of these most important quality indicators, are very close to editions held together with threads. The advantages of this method of binding the blocks should be attributed to the fact that it can be used with equal success both in large-scale and small-scale production of book editions in a binding cover.

Assessment of the quality of notebooks sewn with thermal threads. The quality of notebooks sewn with thermal threads is assessed according to the following indicators: 1) the accuracy of the position of the thread staples on the root folds of the notebooks (tolerance of 0.5 mm); 2) the strength of welding of the legs of the thread staples (nominal value 6 N @ 0.6 kgf, tolerance ± 1 N @ 0.1 kgf). The first indicator is assessed using a LI-3 measuring magnifier with a graduation of 0.1 mm, and the second - using a dynamometer with a maximum load force of at least 300 N (30 kgf), equipped with wide jaws for securing stitched notebooks.

Factors affecting the strength and durability of the sewing and adhesive bonding of blocks. The strength and durability of the sewing-adhesive bonding of the blocks depends on the strength of the threads, the strength of the welding of the legs of the thread staples, the adhesive bonding of the legs of the staples and block notebooks to each other, the type and strength of the edging material. The strength of the threads is sufficient: it usually exceeds the strength of sewing threads No. 30, used for block sewing, by about 1.5 times. The strength of the welding of the thread legs depends on the temperature of the working tools and the type of paper (Fig.5.22).

With an increase in the temperature of the heating tools, the welding strength of the legs of the thermofilaments increases, reaches a maximum value for many types of paper in the temperature range of about 250-265 ° C, after which it decreases. For calendered types of paper (for letterpress No. 1, offset No. 2, illustration No. 1), the optimum welding temperature of the legs is 255 ° C, and for chalk overlay letterpress - 265 ° C. Typically, highly-calendered and chalk-coated papers give about 1.5 times lower weld strength than stock-coated and calendered papers. In some types of paper, the strength of the welding of the legs of the thread staples decreases rapidly immediately after reaching the maximum strength or remains constant up to a temperature of 280 ° C.

In the process of gluing, edging and drying the spine of the block, the strength of the sewing-adhesive bonding increases by about 1.6-2 times and reaches an average of 10-11 N (1.0-1.1 kgf).

5.2.13. Mechanical binding of book blocks

Mechanical is the name given to methods of fastening book-type blocks that use metal or plastic fasteners or devices. According to the type of hole formation in the root zone of the block and the type of fasteners and devices, mechanical methods of fastening the blocks are divided into fastening with spirals and combs, screws and rivets, clamps and clips.

Binding with spirals and combs. To carry out the fastening of blocks with spirals, it is necessary to perform two operations: to make a perforation of the holes in the root zone and to wind the spiral into the holes of the perforation. In large and medium-scale production, perforation is performed on machines of the EX 380, 610 or 700 type (by James Byrne International, Sweden), in which perforation can be made sheet by sheet or in stacks from 3 to 30 sheets. In small-scale production, desktop "office" perforators or universal punching and creasing machines of the 2UPB-500 type (Kharkiv ZPM, Ukraine) are used. For fastening with metal or plastic spirals, small round holes with a diameter of about 2-3 mm are perforated in 4: 1 ¢¢ increments (four holes per inch, every 6.35 mm). Coils are wound onto blocks on semi-automatic 52 E type (Renz, Germany) or manually.

When fastening book blocks with wire or plastic combs, a more sparse and coarse perforation with a step of 3: 1 ¢¢ and 2: 1 ¢¢ is usually used, and when fastening with wire combs, the holes are made square, and when fastening with plastic combs - rectangular, narrower and longer ... Manufacturers offer fastening combs of various sizes depending on the thickness of the book blocks to be fastened (Table 5.4).

The filling of the wire combs into the prepared book block and their compression to form closed rings, completely covering the edge of the root zone, are carried out on semi-automatic machines "Renz-Autobind", the hourly capacity of which is about 1 thousand A4 blocks, or on small-sized table-type devices with manual actuator drive. Manufacturing companies supply plastic combs twisted into tubes, so when they are inserted into perforation holes in Attacombo Super machines (Attalus international corporation), the combs are unwound so that their teeth can enter the perforation holes. The compression of the plastic combs occurs due to the restoration of the highly elastic deformation of the main polymer component.

The advantages of the methods of fastening blocks with spirals and combs include their relative simplicity of technology, which does not require highly qualified maintenance, the possibility of their use in small enterprises and in offices, full (180 °) opening of book-type products, the possibility of using covers of various designs (Fig.5.23 ).

The disadvantage of methods for fastening blocks with spirals and combs is the use of part of the spine field, which somewhat reduces the percentage of paper use.

Binding with spirals and combs is used in the production of wall calendars, diaries, various catalogs, music and general notebooks, notebooks, and abroad - in the manufacture of some textbooks.

Fastening blocks with screws and rivets. When fastening the blocks with screws and rivets, two or three through holes with a diameter equal to the size of the sleeve or shaped nut of the fastener are punched or drilled in the root zone. Fasteners are inserted into the finished holes manually, after which the rivets are pressed with a hammer blow or in a lever and screw press. When using threaded fasteners, the block is fastened with a screwdriver or, if there is a notch on the screw head, manually.

This type of bonding is mainly used in the production of albums for various purposes and folders with paper for explanatory notes to diploma theses and projects. Good disclosure of the albums is ensured by the use of fabric hinges connecting the sheets of the block with the spine strips of cardboard.

Fastening blocks with clasps and clips. Fastening of blocks consisting of single sheets can be performed with spring locks, which are securely riveted to welded plastic binder covers. The spring lock can have from 4 to 6 pairs of half rings, which in the finished product fit tightly into rings. In other versions of locks, the sheets of the block are tightly squeezed along the spine by a spring-loaded bar, the position of which is fixed by a lever and a latch. The first version of the lock fastening involves the perforation of round holes with a diameter of about 4 mm in the root zone of the block. In the finished product, the sheets of the block are fastened in the same way as when fastening with combs, but the number of elements fastening the block is about an order of magnitude less.

When using locks with a spring-loaded bar, the sheets of the block are kept from falling out of the clamp by friction forces, which depend on the pre-tension of the spring, the thickness of the block, the smoothness of the paper and the position of the sheet in the block. In case of careless handling of the block or with the clamping device, the sheets of the block may fall out, therefore this type of block fastening is used in cases where the order of block assembly does not matter: in the production of white goods, for storing various documents, etc. the bar can be attributed to the fact that the block does not require any preparatory operation, and the main disadvantage is the high cost of binding covers with built-in spring locks.

In essence, the fastening of blocks with clips (springy U-shaped fastening elements with "wings" converging at a certain angle) is similar to fastening blocks with locks with a spring-loaded bar: in both versions, the sheets of the block are held by friction forces. The difference is that the clips are usually independent fasteners. When using clips, they must be selected according to the determining size, according to the thickness of the block with a small margin, and cut the blanks in accordance with the height of the blocks.

As an independent type of binding, this method is used mainly for storing archival documents. Sometimes binding with clips is used in the production of directories and product catalogs of rapidly developing industries, since this type of bonding makes it easy to supplement a block with sheets or replace some of its sheets with new ones.

Sewing with threads is the oldest way to fasten book blocks, as it was also used to fasten handwritten books. In world practice, three types of sewing blocks with threads are used: patchwork, saddle stitch and set-in. Pocket sewing has two varieties: with gauze and without gauze.

For almost two millennia, handwritten and printed books were sewn at a fair pace with thin tendons and threads by hand using a simple sewing machine (a wooden board with a U-shaped stand on the edge), which allows you to fasten the bundles or braids in a taut state. The technology of pocketbook sewing of book blocks was mechanized only at the end of the 19th century, in 1984 (Bremer firm, Germany) and automated in the 50s. 20th century (THE USSR). Currently, sewing of blocks with threads is carried out on specialized semiautomatic sewing machines and automatic machines. Specialized machines are designed for sewing blocks with simple booklet stitching. Universal sewing machines allow you to sew blocks on gauze with simple and adjustable binding stitch and without gauze with simple and adjustable booklet stitch.

For sewing, strong nylon and cotton threads are used with a linear density of about 50 tex (g / km) and printing cotton-polyester gauze "NSh" (for sewing machines). When sewing without gauze, the sheets of notebooks and notebooks are fastened to each other with three to six stitches, the number of which depends on the height of the book block, and the outer notebooks of the block are glued to the neighboring ones with a narrow strip of glue to prevent them from coming off due to the loosening of the seam after cutting the threads between the blocks ... When sewing on gauze, a wide strip of spine material is additionally attached to the spine of the block with the outer elements of the seam, which serves to securely fasten the binding cover to the block, and a gauze loop is made between the blocks, which, after cutting manually on the machine's receiving table, forms valves of the spine material, width which can be 18 or 22 mm, depending on the format and thickness of the block.

The productivity of semiautomatic sewing machines is about 60 notebooks per minute, and the maximum technical speed of the machines reaches 100-130 cycles / min. However, even at a high sewing speed, the labor intensity of sewing blocks consisting of 20 - 30 notebooks makes up a significant part of all labor costs required for stitching and binding processes. As a result, at the present time, notebook sewing with threads is used mainly for binding, blocks of publications designed for a long service life and (or) intensive use - collections of essays, encyclopedias, multi-volume dictionaries and reference books, textbooks, etc. it is used mainly in the manufacture of editions in a binding cover, if further processing of blocks with a thickness of 12 - 40 mm is supposed to be processed on automated tray lines, on which gauze is glued after mechanical processing of the spine. This sewing method is sometimes used in small-scale production of multi-volume publications in the cover with a block thickness of more than 15 mm, if other methods of fastening cannot be used (for example, due to lack of equipment) or they cannot provide the required values ​​of strength, durability and openability of the publications.

Block sewing of blocks with a saddle stitch has limited application, for example, in the large-scale production of small-volume children's publications in a binding cover. This method of fastening is used in the De Flores production line (McCain, USA), in which blocks are sewn with a Singer sewing machine (USA) with a two-thread chain stitch with a stitch length of up to 2 mm.

Sewing book blocks with a set-in thread can be carried out on special machines of the firm "Singer" with relatively thick threads with a linear density of about 100 tex. Abroad, this method is widely used in the production of publications designed for a long service life or intensive use in selective reading - textbooks, reference books, encyclopedias, etc.

Before we start sewing the block, we will choose the sewing method. It has long been believed that the best results are obtained by sewing on cords, the results are somewhat worse when sewing on braid, and sewing on gauze can be performed only with significant experience in this area, since the blocks can be weak, with uneven roots. One way or another, many bookbinders associate the operation of "sewing a book block" with the obligatory presence of a bookbinding machine, or rather, that part of it, which is intended for stitching notebooks into a block. The device for performing block sewing is easy to make in a home workshop (Fig. 6). It allows you to carry out any kind of sewing.

Rice. 6. Sewing device (fragment of the bookbinding machine)

The sewing pattern for cords is shown in fig. 7, a. To sew on cords, it is necessary to align all the notebooks of the book block along the spine and upper edge, mark the spine for sewing and make cuts in it for cords of such depth so that the cords along their entire diameter are flush with the spine of the block. The cuts should be made of the same depth, which is easiest to accomplish using metal templates specially made for this purpose, located on both sides of the book block and squeezed by two clamps. It is not bad to "precipitate" the notebooks of the block with a thin metal ruler inserted into the middle of each notebook and pressed with an edge to the inner fold of the notebooks before sawing the spine part.

Figure 7. Schemes for sewing notebooks into a book block: a - sewing on cords; b - sewing on the braid; c - sewing on gauze; d - sewing followed by pasting with gauze; d - sewing a set-in; f - stitching of individual notebooks and a layout template

The extreme cuts through which the cord does not pass are made with a jigsaw or cut with a knife.

This method is used only when sewing a block with glued endpapers (this will be discussed below).

Usually in the literature, sewing in two notebooks is recommended for sewing a block on cords. This method is quite simple, but it does not give a very strong connection of the block notebooks. Therefore, it will be better if, using thin strong threads (silk or nylon is better, but ordinary bobbin threads No. 10 or No. 20 are suitable), sew notebooks on cords in accordance with the scheme (Fig. 7, a).

In any case, start sewing from the first notebook. If the design of the book block with glued endpapers is chosen, then we can assume that all the notebooks of the book block are already ready for sewing, that is, slots for the entry and exit of the stitching thread are made in the spines of the notebooks. When stitching endpapers are installed on the first and last notebooks, their spine parts are not cut through, but pierced with a needle and thread or an awl before sewing in accordance with the markings for the cuts of the spine part of the book block.

Having laid the first notebook on the bottom plate of the sewing device "face down", insert the needle and thread into the extreme slot in the spine of the notebook (or into the corresponding hole with the glued endpaper), after making a knotted loop at the end of the double stitching thread. The needle is inserted from the outside of the spine and is output into the first slot for the cord from the inside of the notebook, after which, bypassing the cord from the outside, it is directed again into the same slot, and then passed in the same way through the second and subsequent slots. The location of the cords on the stitching device should exactly correspond to the location of the slots in the spine of the unit to be stitched, and the tension of the cords should be adjusted so that they do not sag, but are sufficiently elastic. Traditionally, twisted hemp rope or twine consisting of 3-5 yarns is used as cords, but if it is not available, a cotton cord twisted from separate threads can also be used, but the strength and durability of sewing on it is lower than on hemp twine. If necessary, ready-made cords are replaced with bundles of harsh sewing threads glued with starch paste. The beam diameter is 1.5–2 mm.

A needle with a thread, which came out of the last slot of the first notebook, goes out into the corresponding slot of the second notebook, which fits onto the first. Further sewing of the second notebook will be carried out in the same way as the first. After the thread comes out of the extreme slot of the second notebook, insert the needle and thread into the initial loop of the thread and carefully so as not to cut through the folds of the notebooks, pull the thread of both the first and second notebooks, after which we will continue sewing the third notebook, when sewing which (and all subsequent ones) the stitching thread must be constantly pulled. When the thread comes out of the last slot of the third notebook, you should ensure that it is fastened to the second notebook. To do this, direct the needle from the side of the spine to the side of the cut obliquely between the first and second notebooks under the thread connecting them. It is better to do this with the eye of the needle forward, so as not to spoil the root part of the notebooks. Having checked the thread tension, we can proceed to sewing on the fourth and subsequent notebooks. When finishing sewing, thread one of the outer seams several times and remove the stitched unit from the stapler. Cut the ends of the cords so that on both sides of the block there are 15–20 mm ponytails.

Coat the stitched block from the spine side with glue and place it under the press until it is completely dry.

Sewing on tape is not much different from sewing on cords. The difference is that when sewing on the braid, you do not need to saw through the notebooks of the block, and the sewing is done so that the braid is not stitched with threads. The sewing pattern for the tape is shown in fig. 7, b.

When sewing on gauze, as shown in fig. 7.in, the notebooks are sewn to the gauze. In all cases, the spine of the block after sewing must be glued and pressed until completely dry, as described above. For the convenience of sewing on braid and gauze, it is recommended to make a ruler out of cardboard, on which you should mark the entry and exit of the needle with the thread through the roots of the notebooks. Using such a template, you can mark the notebooks from the inside along the fold, applying the points of future punctures of the notebooks of the block with a needle.

Keep in mind that the gauze used for bookbinding is designed to provide it only with the strength of fastening the notebooks of the block, but also the possibility of long-term use of the book, for which the threads of the gauze base, as the most durable, are placed across the spine of the block. The location of the warp threads is easy to determine: along the base, the gauze breaks with less effort than across it. The width of the gauze strip for sewing blocks should be taken 25–30 mm less than the height of the book block.

One more tip: if you have to tie on the sewing thread when sewing the block, fold the ends of the old and new threads and tie them in one knot in the manner of a usual tailor's knot when sewing with a needle by hand. When tying threads, especially slippery ones, do not use a double knot, as it will untie when the thread is pulled.

The above methods of sewing book blocks from notebooks are classic types of saddle stitching. As you can see from the above, they require the use of a sewing device. However, in the absence of the latter, the notebooks are stitched into a block without such a device.

Aligning the book block along the spine and the upper edge, it is clamped with a clamp and the spine of the block is marked along a ruler or using a template, that is, pairs of parallel lines are applied to the spine (perpendicular to it) with a distance of 20-25 mm between them. For books less than 20 cm in height, two pairs are sufficient, with high heights - three or four.

Then take a double-folded thread (its length is 10-15 cm more than the number of notebooks multiplied by the distance between a pair of parallel lines marking the spine), thread it so that there is a loop at the long end of the double thread (the middle of the double-folded single thread), and open in the middle of the first notebook 1 (Fig. 7, d), insert the needle outside the spine to the point 1 leaving a loop of thread behind the spine. Derived through the point 2 direct the needle and thread to the point 3 the next (second) notebook II, opened in the middle. A needle with a thread, released on the second notebook through a dot 4 , put in the loop sticking out of the puncture 1 ... Carefully so as not to cut through the folds of the spine, pull the thread, thereby fixing the stitching of the first two notebooks, and then insert the needle into the point 5 notebook iii and, bringing it through the dot 6 , lock the stitch by passing the thread between the first and second notebooks under the connecting stitch 2 -3 , then insert the needle into the point 7 exercise books iv, etc. When you have finished sewing the first row of stitches, secure the end of the thread by tying two or three knots around the stitches across the spine and start sewing the exercise books along the next row of markings. Coat the stitched block with glue along the spine and press it in until it is completely dry.

Books with wide margins, as well as sets of newspapers or typed sheets, can be bound by the sewing method (that is, along the spine of the block), as shown in Fig. 7, d. Having aligned the block along the spine and the upper edge, it is glued along the spine and pressed in until it is completely dry. It is advisable to glue over the spine with a cloth or gauze tape with an approach to the first and last notebooks of a block of cloth tapes about 10 mm wide. Having retreated 5 mm from the root part of the block on a line parallel to the spine, drill an odd number of holes with a diameter of about 2 mm (or pierce them with an awl), evenly spaced at a distance of 25-30 mm from each other along the entire height of the block. Drilling is best done by clamping the spine of the block between two plywood, which will save the block from tearing the paper when the drill comes out of the block. Sew the block through the holes obtained with a coarse thread (Fig. 7, e), and tie the ends of the thread, pulling it together.

It should be warned that the block stitched in this way is inconvenient for use: it does not open well.

When sewing books, the cropping of which is undesirable, it is recommended to pre-stitch the notebooks with their subsequent connection into a block (Fig. 7, f).

In this case, using a ruler template, combining the risk a with the top edge of the notebook, mark the stitches of future sewing so that there are six stitches on each notebook. Two stitches marked on the pattern with numbers 1–2 and 3–4 , are made smaller than the others, marked with letters a - h... It is advisable to make the distances between the stitches less than the length of the stitches themselves. Points a and s should be 25-30 mm from the upper and lower edges of the block.

First, notebooks are sewn together - each separately - through punctures in the folds of the notebooks 1–2 and 3–4 ... Sewing should be done with a double thin thread and fix the second stitch with a knot. The thread is cut so that a 6–8 mm “tail” remains near the knot. The stitched notebooks are stacked, aligned by collision, pressed in and glued along the spine. The “tails” of the threads left after the notebooks have been stitched should be evenly distributed over the spine of the block smeared with glue. If you stick gauze on the block spine processed in a similar way, then after the glue dries, the block can be stitched in accordance with the markings, as shown in Fig. 7, without fear that individual sheets of notebooks will change their position in the block.

Special mention should be made of the sewing of book blocks made by a sewing method. Note that knowledge of such sewing techniques is also useful in the manufacture of book blocks from sheet material, for example, from typewritten sheets.

Sewing in a seamless way begins either with cleaning the glue residues of the title and last pages of the book (if the book block is intact), or with laying all the sheets of the book in an even pile. Then the first and last 3-5 sheets of the book are glued to each other along the spine field, applying a 3-4 mm wide strip of glue along the spine along the inner margin, after which the block is clamped with a clamp with the spine outward so that the spine edge with a width of about 4 mm (fig. 8).

Rice. 8. Preparation of a block with a seamless fastening of the spine to the binding

Rice. 9. Scheme of strengthening the sewingless root: 1–2, 3–4 - grooves forming a "dovetail"

The spine of the book block is treated with fine emery paper, removing the remnants of the paper cover from it (up to the glue layer) or creating a smooth surface of the spine when it comes to sheet material. With a hacksaw with fine teeth (it is convenient to use slotting), the grooves in the block spine are cut at an angle of 45 ° to its base to a depth of 3-4 mm. The grooves are paired dovetail grooves evenly distributed along the spine (Fig. 9). Usually 3-4 pairs of grooves are sufficient. The distance between the grooves of the pair along the spine does not exceed 25–30 mm, and the extreme cuts must be at least 15 mm apart from the upper and lower edges of the block.

Dovetail winding starts from the groove 1 the first pair of cuts. The winding is carried out with a strong thread (preferably nylon), laying its turn to the turn with sufficient interference (only 2-3 turns are needed). Without breaking the threads, make the same number of cuts, using the second pair of cuts, etc. The last pair of grooves are placed in 1-2 turns more than in the previous ones, and without breaking the thread (it will already pass along the opposite side of the book block ), return to the first pair of grooves, alternately winding 1-2 turns on each "dovetail" of the block. End and beginning of thread in the groove 1 , tied with a knot, trying to get it inside the groove.

It remains to glue the spine of the block, making sure that the glue gets into the grooves and soaks the threads in them well. If the grooves turned out to be too wide, pieces of hemp or cotton twine (cord) impregnated with glue are laid in them, ensuring the reliability of the block spine. The experience of amateur binders and the authors themselves has shown that such books open better than sewn-in books.

It is necessary to glue the endpapers to the finished book block, without which it is impossible to connect the block with the binding covers. Endpapers are glued to the first sheet of the first and last sheet of the last notebook of the block. Note that the endpapers should have a sectional cutting, that is, the sectional direction of the endpaper paper grains must coincide with its spine fold. To determine the direction of the fibers, a small section of paper is moistened with water: in the fractional direction, the paper is slightly deformed, and in the transverse direction it becomes wavy.

Three types of endpapers are used in modern books.

Most often, there is a glued endpaper (Fig. 10, a), which is a sheet of paper folded in half. The height of the endpaper is equal to the height of the book block, and the width is twice the width of the notebook of the block. To attach endpapers to notebooks, a 3-4 mm wide strip of glue is applied along the spine fold of the endpaper and glued to the spine of the corresponding notebook so that the fold of the endpaper is flush with the spine of the notebook or the spine of a book block. If you follow the advice of many bookbinding aids and attach the flyleaf at a distance of 3-4 mm from the spine of the block, then after inserting the block into the covers, the flyleaf may be torn the very first time you open the book!

In books of large volume, a glued endpaper with a border is used, which increases the strength of the glued endpaper (Fig. 10, b). In this case, after gluing the endpaper to the notebook of the block, the spine of the notebook is edged with a strip of fabric or strong paper about 15 mm wide, thickly greased with glue. A strip of edging material is glued so that it goes 3–4 mm with one of its edges on the inner side of the notebook, goes around the spine of the notebook and for the most part goes onto the glued endpaper. The length of the edging material is equal to the height of the block.

Editions designed for long-term storage and frequent use are usually supplied with a composite endpaper with a folder (Fig. 10, c). The flyleaf consists of two sheets of paper: sheet 1 has a width of 5-6 mm less than the width of the notebook, and the sheet 1 - as much wider than it. Falchik 4 made of well-starched fabric, its width is about 15 mm. The length of the folder and the height of the endpaper sheets are equal to the height of the notebook. 2 book block.

It is convenient to assemble this flyleaf in this sequence. Fold the flyleaf sheets with their front sides facing each other so that the narrow one lies on top of the wide one, and the root part of the wide leaf protrudes from under the root part of the narrow one by 3-4 km. The narrow sheet is covered with a sheet of auxiliary paper with an indent from the spine of the narrow sheet by 3 mm. The edges of the two sheets of the endpaper protruding from under the auxiliary paper are smeared with glue, the auxiliary sheet of paper is removed and both halves of the endpaper are pushed onto the side edge opposite the spine. A fold is placed on top, aligning it along the border of the glue strip of a narrow sheet, and carefully wipe it in the places where it is glued to the endpaper sheets. The endpaper is applied to the notebook, aligning it along the side edge, grease the protruding part of the folder along the spine by 5 mm and glue it to the inside of the notebook, gently bending and rubbing it.

Rice. 10. Design of endpapers. a - glued endpaper; b - glued endpaper with edging; c - a composite endpaper with a fold; 1–1 - endpaper; 2 - block notebook; 3 - adhesive layer; 4 - edging

After attaching the endpapers, the glued spines of the book blocks must be pasted over with gauze so that the edges of the gauze 15–20 mm would go onto the endpapers from the side of the block spine. If the block was sewn on a tape, the ends of the tape 15–20 mm long are glued to the outer sheets of the endpapers. The ends of the cords (when sewing on cords) must be tousled and flattened before gluing to the endpapers, for which you can use an ordinary awl, but it is better to make a special tool - a rasp. It is a thin steel plate 0.5–1 mm thick, in which oblique cuts are made (a drawing of the racking will be given below). The end of the cord is grasped into the slot and on the surface of the plate, using a needle or awl, it is fanned out or flattened with a hammer.

After gluing the spine of the book block with gauze, it should be dried under a press. To protect the glued areas from sticking to the working surfaces of the press or clamp, use pads made of waxed paper or polyethylene.

The production of book blocks includes only two operations - their assembly and fastening, but these are operations of paramount importance, since the quality of their execution determines the most important consumer properties of book publications - ease of use, their strength and durability.

Collation is a selection in strict sequence of all notebooks or sheets of a book block or complete publication. In accordance with the design of book editions, book blocks are assembled by an insert and a selection (Fig. 5.1); complete editions, consisting of separate sheets, are completed only with a selection.

Collecting blocks with a tab is used only in the manufacture of small-volume book editions with a block thickness of up to 4 or 5 mm - editions in the cover and in the cover, respectively. This limitation is explained by the fact that with a thicker block, the width of the sheets and the front margins of the inner spread of the finished book will be more than 3-4 mm less than that of the outer sheets of the block.

In small-scale production, book blocks are assembled manually. When collating with a tab, the feet of notebooks are laid on the table in the order of the notebook numbers from left to right, and the collating is done from right to left, putting the inner notebooks into the outer ones and then the entire block into the cover. When collating, the feet of notebooks are placed in the cells of a special table, the collating begins with the last notebook or sheet of the block, laying them on the palm or cardboard corner.

In the medium and large-scale production of publications in the cover, the collation with the insert is carried out on lining-sewing machines and lining-sewing-cutting units (HSRA). On saddlery and sewing machines, the notebooks and the cover are manually opened in the middle and sequentially thrown - the inner one onto the chain conveyor, and the outer and the cover one on top of each other as they move to the sewing machine operating in automatic mode. In the NSAID, all operations, except for loading feeders, are automated. Modern saddle stitches have a maximum technical operating speed of 167 to 300 cycles / min.

At large printing enterprises, the assembly of blocks with a selection is carried out on collecting machines, for example, 891 and 892 (Bremer-Stahl, Germany), the number of stations for loading notebooks can reach 42, and the maximum technical speed is 120 cycles / min. Before work and periodically in the process of work, the feeder of the collecting machine stations are manually loaded with stacks of notebooks in a strict sequence of their signature numbers. While the machine is running, the notebooks are taken out by feeders onto the assembly conveyor, which, during the machine's operation cycle, moves to the width of one store and brings the assembled blocks onto the receiving table or transfers them for further processing (Fig. 5.2).

On collectors with a large number of stations, two or three book blocks can be selected in one cycle, but if the number of notebooks in a block is much more than the number of stations in the machine, then the two halves of the block are assembled separately, after which they are connected manually. In case of glued seamless binding (KBS) of book blocks, the collecting machine is connected to the KBS unit, which makes it possible to organize continuous in-line production already from the block packing operation, the speed of such units can reach 300 cycles / min.

The complete blocks must contain the full number of good-quality notebooks of this edition, which must be arranged in a given order, with fields of the same name in one direction. Notebooks must be clean and undamaged. For visual, quality control of the blocks assembled by the selection, at the place of the spine folds of the notebooks, notebook and order marks are printed in advance, which in the assembled block form a correct "ladder" and a transverse strip on the spine (Fig. 5.3).

The fastening of book blocks, consisting of separate sheets or notebooks, can be carried out in various ways, each of which has its own advantages, disadvantages and an advantageous area of ​​application. According to the version of the technology for fastening book blocks, all methods are divided into tetrad and block-by-block, and by the type of fastening materials, parts or devices - into sewing, glue, sewing-glue and mechanical. By the type of stacking of notebooks or a block in the sewing machine and the location of the fastening elements, sewing fastening can be performed in the slot (along the spine fold of the notebooks), stitching (along the spine fold of the block completed with the tab) and stitching (along the spine of the block completed with the selection). Adhesive bonding is performed along the surface of the spine, and mechanical methods - along the spine field of the block.

When binding book blocks, typical only for sewing with threads and wire, all sheets of each notebook are fastened with transverse elements of a thread seam or legs of wire staples, and the notebooks are sequentially attached to each other using the outer elements of the seam and spine material or, when sewing with wire, - only with root material. With block-by-block binding, the sheets or notebooks of the book block are fastened simultaneously in one or several (when sewing with saddle stitch and set-in with threads - for several dozen) cycles of equipment operation.

The technology of notebook block binding provides high strength, durability and good opening of book publications, but its high labor intensity, which is directly proportional to the number of notebooks in a book block, does not allow this operation to be included in continuous production. The technology of block-by-block fastening of blocks, the labor intensity of the main variants of which does not depend on their thickness and format, ensures high productivity of the leading equipment, allows organizing continuous in-line production of the largest part of the chain of technological operations, starting with the assembly of blocks, and not with their processing, as is done with fastening blocks. When blocking blocks together, a construction of a book edition is usually created with an equal strength in the thickness of the block, but the outermost (when collating with a tab - outer and inner) sheets of the block are held together less firmly. Opening of publications depends mainly on the type of block-by-block fastening and can vary from complete (when fastening with spirals, combs, locks) to poor (when sewing with a wire, fastening with screws and rivets).

In sewing methods, when sewing blocks with threads and wire, the fastening materials are threads or thin wire, in adhesive sewing methods (KBS) - glue (additionally - a cover or edging material); in the sewing and glue method, the sheets of each notebook are fastened with thread staples, and the notebooks with each other - with glue and edging material. In mechanical methods of fastening blocks, metal or plastic fasteners are used - screws with nuts, rivets, spirals, ring-shaped combs, clips and locking devices with split bows.

Sewing methods for fastening blocks allow you to obtain high strength and durability of publications, but with a significant thickness or height of the block, it is very laborious. Glueless binding, depending on the load of the printing company, can be carried out on relatively simple semi-automatic equipment or on high-performance production lines, on which most of the chain of binding and binding operations can be performed. It is characterized by low labor intensity of the technological process and high production profitability. At the same time, KBS gives good results only with careful selection of glue for paper and strict adherence to the modes of performing technological operations. Sewing and glue binding of blocks combines the advantages of sewing and glue bonding methods, provides the possibility of organizing continuous flow production, starting with the collection of book blocks, good strength, durability and opening of publications. Its disadvantages include the fact that it can be used when processing sheet printed products, since the binding of notebooks with thread staples is performed on folding machines equipped with sewing machines. Mechanical methods of fastening allow reliably fastening blocks of almost any thickness and any format on simple small-sized equipment. They provide high strength and durability of various book-type products, but when using them, a preliminary operation of cutting or drilling holes in the spine zone of the block is required, the percentage of paper use is significantly reduced.

It can be argued that the maximum strength and durability of book editions is provided by the binding of blocks with threads, somewhat less - by wire and thermal threads, and the least - by glued seamless fastening. Full disclosure of book editions is ensured by the fastening of blocks with spirals, combs and locks, very good - tetrad sewing with threads and wire and sewing and glue fastening, good - KBS, and bad - sewing with threads and wire set-in, fastening with screws, rivets and clips. In terms of the productivity of the leading equipment, labor costs and profitability of production, the best indicators are for saddle-stitching and glueless bonding, good for sewing-glue bonding, the worst for tetrad sewing with threads and wire and mechanical bonding methods.

Sewing with threads is the oldest way to fasten book blocks, as it was also used to fasten handwritten books. In world practice, three types of sewing blocks with threads are used: patchwork, saddle stitch and set-in. Pocket sewing has two varieties: with gauze and without gauze.

For almost two millennia, handwritten and printed books were sewn at a fair pace with thin tendons and threads by hand using a simple sewing machine (a wooden board with a U-shaped stand on the edge), which allows you to fasten the bundles or braids in a taut state. The technology of pocketbook sewing of book blocks was mechanized only at the end of the 19th century, in 1984 (Bremer firm, Germany) and automated in the 50s. 20th century (THE USSR). Currently, sewing of blocks with threads is carried out on specialized semiautomatic sewing machines and automatic machines. Specialized machines are designed for sewing blocks with simple brochure stitch (Fig. 5.4) without gauze. Universal sewing machines allow you to sew blocks on gauze with a simple and adjustable binding stitch and without gauze with a simple and adjustable brochure stitch.

For sewing, strong nylon and cotton threads are used with a linear density of about 50 tex (g / km) and printing cotton-polyester gauze "NSh" (for sewing machines). When sewing without gauze, the sheets of notebooks and notebooks are fastened to each other with three to six stitches, the number of which depends on the height of the book block, and the outer notebooks of the block are glued to the neighboring ones with a narrow strip of glue to prevent them from coming off due to the loosening of the seam after cutting the threads between the blocks ... When sewing on gauze, a wide strip of spine material is additionally attached to the spine of the block with the outer elements of the seam, which serves to securely fasten the binding cover to the block, and a gauze loop is made between the blocks, which, after cutting manually on the machine's receiving table, forms valves of the spine material, width which can be 18 or 22 mm, depending on the format and thickness of the block.

The spine material is harvested in the form of rolls, the width of which is the formula "src =" http://hi-edu.ru/e-books/xbook280/files/4.gif%20 "border =" 0 "align =" absmiddle "alt = "(! LANG:= B - 35 = B - 25, where B is the block height before, and in - after trimming from three sides, mm.

The productivity of semiautomatic sewing machines is about 60 notebooks per minute, and the maximum technical speed of the machines reaches 100-130 cycles / min. However, even at a high sewing speed, the labor intensity of sewing blocks consisting of 20 - 30 notebooks makes up a significant part of all labor costs required for stitching and binding processes. As a result, at the present time, notebook sewing with threads is used mainly for binding, blocks of publications designed for a long service life and (or) intensive use - collections of essays, encyclopedias, multi-volume dictionaries and reference books, textbooks, etc. it is used mainly in the manufacture of editions in a binding cover, if further processing of blocks with a thickness of 12 - 40 mm is supposed to be processed on automated tray lines, on which gauze is glued after mechanical processing of the spine. This sewing method is sometimes used in small-scale production of multi-volume publications in the cover with a block thickness of more than 15 mm, if other methods of fastening cannot be used (for example, due to lack of equipment) or they cannot provide the required values ​​of strength, durability and openability of the publications.

Block sewing of blocks with a saddle stitch has limited application, for example, in the large-scale production of small-volume children's publications in a binding cover. This method of fastening is used in the De Flores production line (McCain, USA), in which blocks are sewn with a Singer sewing machine (USA) with a two-thread chain stitch with a stitch length of up to 2 mm.

Sewing book blocks with a set-in thread can be carried out on special machines of the firm "Singer" with relatively thick threads with a linear density of about 100 tex. Abroad, this method is widely used in the production of publications designed for a long service life or intensive use in selective reading - textbooks, reference books, encyclopedias, etc.

Sewing of book blocks with wire in the production of books in the cover of medium, large and large volumes began to be used in the last quarter of the 19th century: the first multi-device wire stitching machine was created by the Bremer Brothers company (USA) in 1875 - 1876. It was a semi-automatic machine for the tetrad bonding of blocks on the root material. On such machines, wire sewing is carried out in a socket, in which the wire staples formed by 4-7 sewing machines pierce the half-open notebook from the inside, and the legs of the staples are bent over the spine material.

In world practice, three types of sewing with wire are used: patchwork in connector and block stitching (Fig.5.5) and set-in. Loose wire sewing has been widely used (along with thread sewing) for about 80 years, but it competed with automated sewing with threads in the second half of the 20th century. this method could no longer. In the 70s. 20th century The machines for pocket wire sewing were discontinued, but now they are still used at printing enterprises in the production of albums, atlases, stockbooks and other small-circulation products of almost any format and block thickness.

Block-by-block sewing of blocks with a saddle wire can be performed on wire stitching machines of type 4BSh1-30 (Ukraine), on saddle-stitching machines of type 731 and 735 (enterprise "Polygraph", GDR) and on saddle-sewing and cutting units (N11RA) of various models. Block-by-block sewing of blocks with a wire stitching can be performed on 4NSH-30 wire stitching machines and on collating and sewing machines, for example, 891-D (Bremer-Stahl, Germany).

One-piece stitching machines are designed to bond small to medium editions and blocks, and they can quickly be changed from saddle stitching to stitching sewing or vice versa. The productivity of these machines is low (14 - 20 copies / min for saddle stitching and 10 - 15 copies / min for set-in sewing), so they are mainly used in small-scale production of cover books.

Collar sewing machines are called collating machines (see 5.1) equipped with devices for sewing blocks with a set. They are designed for the production of medium volume blocks for cover editions and can be successfully used in medium batch production. In Russia and the CIS countries, these machines have not received widespread use, since such publications currently prefer to be glued without sewing on machines that also perform the subsequent operation of covering the block with a cover. Inserting and sewing machines with manual overlay of notebooks and covers are not widely used due to the high labor intensity of maintenance and low profitability. Widespread use of saddle stitches designed for mass production of cover publications and having a maximum technical speed of 150 cycles / min (model 750, Bremer-Stahl, Germany) to 300 cycles / min (model 301, Müller-Martini, Switzerland").

For sewing, a thin (about 0.6 mm) steel printing or general-purpose wire is used, the diameter of which is selected in accordance with the surface density of the paper. thickness of notebooks or blocks and may differ from the specified in the smaller or larger side by 01-0.2 mm.

The idea of ​​glued seamless bonding (KBS), connecting individual sheets of a book block with only glue, appeared long ago (the first patent was registered in Austria in 1811), but the real possibility of obtaining a strong and durable gluing of sheets at the ends appeared only after the production of polyvinyl acetate (1936. , Germany), the water dispersion of which (PVAD) is widely used in the CBS technology. In Russia and the CIS countries, this method of binding blocks began to be used for binding editions in a cover from the 50s, and for editions in a binding cover - from the 80s. 20th century

According to the technology of preparing the notebooks of the book block for bonding, the methods of adhesive bonding are divided into three groups:

1) with milling the spine folds of notebooks;

2) with partial destruction of folds;

3) without destroying the folds.

In each group, there are three options for the KBS technology, but in this tutorial we will give a description of only those options that have received relatively widespread use in the printing industry in Russia and the CIS countries.

The most widespread use all over the world is the version of the KBS with milling of the spine folds without dissolving (shifting with a "ladder") of sheets, in which spine folds are milled at the completed block by an amount of up to 5 mm, after which paper dust is carefully removed, the spine of the block is glued with a thick (up to 0.8 mm) with a layer of glue, and the block is covered with a cover or edged with spine material. For the production of cover publications using this technology, the Müller-Martini company (Switzerland) produces more than ten models of KES machines and units with a maximum technical speed from 25 (Baby-Pony) to 300 cycles / min (Normbinder SFC). To equip small printing enterprises, various companies produce small-sized semi-automatic KBS machines that perform two or three basic operations: milling and gluing the spine, covering the block with a cover.

Leading firms producing bookbinding and binding equipment produce KBS units and production lines, designed for the production of editions in a binding cover. Such production lines (for example, a line based on the "Systembinder KM" unit of the "Kolbus" company, Germany) are distinguished by the fact that the picking machine is supplemented with a section for gluing or attaching endpapers to the block, the KBS unit works on "cold" glue, the section of the block spine edging is smoldering. , a high-frequency drying device and is complemented by an extended conveyor for cooling and additional drying of edged blocks before their three-sided cutting.

Undiluted high-viscosity PBAD with a dry matter content of about 50% or hot glue based on a copolymer of vinyl acetate with ethylene is used for CBS. Hot glue before work is heated and applied to the spine of the block in the form of a melt with a temperature of 140 to 180 ° C. It does not require drying, as it is fixed during hardening due to natural cooling within a few tens of seconds. KBS imposes special requirements on the paper of the block: it should not be strongly glued and rigid, the best results in terms of strength and durability of publications are provided by porous, weakly glued, thin paper with fractional cutting, - with a machine direction along the spine of the block.

The use of hot melt glue allows to increase the speed of equipment operation by approximately 1.5 times and to fully automate production in operations from block assembly to packaging of finished products. The disadvantages of this version of the KBS technology should be attributed to the fact that hot glue is much more expensive than PVAD, it gives a hard and relatively short-lived film, which worsens the opening of publications and limits the scope of its application to the production of publications with a cover with a short service life.

In Ukraine in the 1960s. a version of KBS with milling of spine folds and reinforcement of the spine with polygraphic gauze, tucked into narrow transverse cuts (slots), was developed and applied, which significantly increases the strength and durability of adhesive bonding of block sheets. This version of KBS is carried out on semiautomatic binding machines (PBS "Sputnik"), in which container (several copies at once) processing of blocks for publications in a binding cover is performed.

In the last decade, the KBS version has received industrial application without cutting the spine folds and gluing the spine folds in the process of folding the sealed paper tape in the folding machines of roll-fed book-and-magazine presses. The gluing of the root folds can be performed by a system of jet devices of the "Optimatic-6000" type (firm "Planatolwerke V. Hesselmann, Germany). The production and processing of book blocks, consisting of such notebooks, can be performed on any machines and production lines of glued seamless bonding when the spine milling section is turned off, which allows us to consider this version of the KBS very promising in the large-scale production of book publications.

Other KBS options are not considered in this discipline.

The method of sewing and glue binding of book blocks was developed in the GDR and was used industrially in the 60s. 20th century According to this method, the binding of a book block occurs in two stages: each notebook of the block, in the process of folding, is stitched with special threads at the place of the spine fold, and the fastening of a complete block consisting of stitched notebooks is done with glue and edging material. Sewing of notebooks is carried out in folding machines equipped with special sewing machines model 311, installed above the transport table of the last folding section. The sewing machine forms two thread staples (Fig.5.6), the legs of which, at the moment of a short stop of the notebook on the transport table of the folding machine, are brought out through the holes formed by thin needles to the outside of the notebook, bent to the side, pressed and welded to the notebook along the line of the subsequent root fold pads heated to about 250 ° C. In the folding machine, depending on the height of the spine of the stitched notebook, from one to four sewing machines can be used, which makes it possible to fasten notebooks with two to eight staples, which are distributed in pairs and evenly along the height of the spine.

Sewing with thermal threads can also be carried out on semiautomatic machines of model 301 and on sewing-folding machines 341 (Bremer-Stahl, Germany). On semiautomatic devices 301, the open notebook is placed manually on the desktop and stitched by pressing the pedal. The 341 sewing / folding machine can be connected to any folding machine to sew a partially folded notebook for the last (third or fourth) fold.

On the 341 machine, one sewing machine of the rotary principle of operation is installed (Fig.5.7), which holds the notebooks in the process of their movement, therefore, the thread staples are distributed evenly along the entire length of the fold obtained in the root fold section, and their number is determined by the height of the spine.

Sewing semiautomatic devices 301 are designed for use in small printing enterprises, where they are used in the production of small-volume cover editions, book-type advertising editions. Folding-sewing machines with 311 devices and sewing-folding machines are designed for medium and large enterprises that produce book products in binding covers.

For sewing with thermal threads, special two-component viscose-polypropylene threads are used, the polypropylene component of which, when sewing, plays the role of hot glue, which turns into a fluid state in the temperature range of 220-270 ° C.

Sewing and glue binding provides for two more operations that are performed after the block is assembled: gluing the spine and its edging, which allows you to obtain strong glue binding of the sewn notebooks to each other and increases the reliability of fastening the legs of the thread staples (Fig.5.8). These and subsequent operations are performed on the 670 glue-edging unit (Bremer-Stahl, Germany), which is used as a piecemeal equipment or works in a production line consisting of a picking machine 891, unit 670, drying device T2, TZ or T4 (of different power - depending on the thickness of the book blocks) and a three-knife cutter SDY-EZ.

Bonding with thermal threads was widely used in Germany (at the end of the 80s of the 20th century in the GDR about 50% of book publications were bonded by this method). In Russia and the CIS countries, it finds limited use, since it involves the use of sheet-fed printing and the receipt of notebooks on folding machines. Due to the indisputable advantage of this method of fastening - obtaining small holes from punctures with thin needles in the spine of notebooks, through which the glue applied to the spine during the processing of the block and spoiling the internal spreads of the book does not penetrate - this method is used in the production of illustrated books printed on coated and highly calendered papers.

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General information about binding blocks with threads

Sewing with threads is one of the oldest ways to fasten individual notebooks into book blocks. At present, despite the rapid development of the sewing-free method, sewing with threads remains the main type of fastening book blocks for important publications (textbooks, reference books, encyclopedias, etc.). Books sewn with threads have the greatest strength and good opening; so far, books bound in other ways cannot compete with them.

There are two types of fastening blocks with threads: block-by-block and tetrad (Fig. 14). With block-by-block binding, all sheets of the block are stitched at the same time. When sewing every notebook of the block is stitched through the spine fold and fastened to the previous notebooks with the same threads.

Block stitching with threads can be performed with a single-thread knot and a double-thread chain stitch. Knot sewing is performed with long stitches (about 10 cm) and is used abroad in the manufacture of low-volume publications, completed with a tab. It is not used in Russia.

Classification of sewing methods with threads.

Sewing blocks with a saddle stitch with a two-thread stitch (it is also called stitching) is performed at the place of the root fold with special sewing machines with one needle and one hook. This type of sewing is used very limitedly in the manufacture of small-format publications (for example, savings books). Block stitching with a thread stitch is carried out with a two-thread stitch. This method is not used in our country and in other European countries, although it is quite common in the book industry in the United States (school textbooks, children's books, encyclopedias, dictionaries, reference books).

In Russia, only regular block sewing is used. It has the following positive features:

1. the design of such a bond is characterized by elasticity and flexibility;
2. sheets in notebooks and in a block are connected quite firmly due to a significant number of stitches, their large total length, elasticity of the threads;
3. durability, since the threads are neutral to paper, glue and the environment;
4. the block has a slight thickening of the spine;
5. any subsequent processing of the block is possible (rounding, folding of folds, crimping, drying, etc.);
6. books have good opening rate.

The principle of operation of the sewing machine

Loose sewing of blocks with threads, which is performed on sewing equipment, consists of the following operations:

• opening the notebook in the middle and transporting it to the sewing machine;
• sewing the notebook through the fold and attaching it to the previously sewn part of the block;
• pushing the stitched notebook onto the receiving table;
• gluing the outermost pairs of block notebooks along the spine;
• blank stitch formation;
• cutting threads between blocks;
• the formation of a gauze loop (when sewing on root material);
• automatic control of the correctness of the assembly of notebooks in the block.

Block diagram of a sewing machine (a) and a technological line for withdrawing and opening notebooks (b)

To perform these operations, the automatic sewing machine has the following components and devices (Figure 15) feeder-opener 1, transport system 2, swinging table 3, sewing machine 4, receiving table 5, glue machine b, control panel 7.

In addition to the components shown in the diagram, there is also a drive, a vacuum system, interlocks and other mechanisms and devices. On the structural diagram, circles show the original semi-finished products that are used in the NSA T - notebooks (fit into the feeder-opener), K - glue (fed into the glue machine), H - threads, M - gauze (used in the sewing machine), B - sewn ready-made book blocks on the receiving table.

Considering the mutual placement of the components of the NSA, we see that the movement of the semi-finished product (notebooks) in it occurs along a n-shaped trajectory, in which three technological lines can be distinguished.

A-B - taking notebooks out of the store and opening them in the middle, B-C - transporting notebooks to the sewing machine, C-D - sewing and outputting stitched blocks to the receiving table. It is advisable to consider the principle of operation of the sewing machine in accordance with the above division.

The technological line for the withdrawal and opening of notebooks (Figure 15, b). Notebooks with a train are placed in a horizontal-type store, resting on the spine on the belts of the conveyor 1, the upper branch of which moves along the flooring.

The notebooks are bounded in front by the front wall. Lever 6 with suction cups fits to the first notebook, which bend its spine towards the sheet output drum 5. Valves of the spine 2 close, and the notebook is removed from the store when the drum rotates clockwise. Then the valves of loop 4 are closed. In the BNSh-6A machine, a reversible sheet-out device is used for notebooks with a loop.

When the drum rotates by rack and pinion 3 from the main shaft of the feeder 8 in the opposite direction (counterclockwise), the notebook opens in the middle and is thrown onto the saddle-like table 7 of the chain conveyor. The drive of all feeder-opener mechanisms is carried out from the cams, which are located at the bottom of the main shaft. The vacuum pump 9 provides the feeder with vacuum. The magazine is replenished with notebooks manually.

Technological line for transportation of notebooks (Figure 16, a). The notebook 1, taken out of the store by the feeder-opener 4, falls on the saddle-like table 3, where it is picked up by the stop 6 of the chain conveyor 2, which is inside the table and moves to the left. First, it passes near the photo head of the device for checking the correctness of the collation 5, then enters the zone of the glue apparatus 7, which applies a narrow strip of glue to the spine zone of the notebook with a rotating disk (section A-A). It should be noted that photo control is carried out only on one notebook in a block, and glue is usually applied to only two notebooks (the second and last). The commands to turn on these devices are received from the machine control unit operating according to a special program.

After passing the glue apparatus, the notebooks are fed to the push-in rollers, which consist of two rotating disks of the lower 9 - with a fixed axis of rotation and the upper 8 - with a movable axis mounted on a swinging arm. The rollers are driven by an individual electric motor, and their peripheral speed is much higher than the speed of the conveyor. When the notebook enters the zone of action of the rollers, the upper rotating roller is lowered onto the spine of the notebook and presses it against the lower one. The notebook, squeezed between the rotating rollers, receives an energy impulse and flies at high speed onto the swinging table 10, which has the same saddle-like shape as the chain conveyor. Notebook head fits to the side stops 11 on the swinging table (movable stop on the front side and fixed on the back).

This is where the transportation ends - the notebook is delivered to the swinging table and is on its saddle in a half-open form, the head touches the side stops.

Technological line for sewing and outputting stitched blocks. After the notebook is brought out onto the swinging table 1 (Figure 16, b), a crimping square 2 is lowered onto its fold, which squeezes the notebook and sits it tightly on the table saddle (position A).

The swinging table 1 begins to move to the sewing carriage 9, while the movable side stop 11 (Figure 16, a), which has a roller at the end of the bar and rolls along the fixed slide 12, shifts the notebook to the right and aligns it before sewing The swinging table approaches the sewing carriage 9 (see Figure 16, b) and stops (position B). At this moment, the swinging table and the sewing carriage form the sewing machine. On the swinging table (inside the saddle) there are punctures (piercing needles) 4 and gates 3 (they are sometimes called yarn feeders), needles and hooks are installed on the sewing carriage. The looping process begins on the basis of the interaction of all the above sewing tools. From under the table, punctures 4 first come out and holes are made in the spine of the notebook. Then the sewing carriage 9 is lowered down, and needles with threads and hooks are inserted into the holes in the fold, the gates grab the thread and transfer it to the hooks. The sewing carriage with all the tools is lifted up the loop of the thread is pulled out. Thus, the notebook is sewn through the fold to the previous ones, and the swinging table returns to its original position to receive the next notebook.

After the end of sewing, the notebooks are pushed onto the receiving table 10 using a push bar (not shown in the diagram). When the push bar is released, the book is held on the receiving table by the brochure needles.

Technological lines for transportation of notebooks (a), sewing and output of stitched blocks (b)

When the table is returned to position A, the upper half of the notebook will lie on the crest of the saddle for a while. Removing it is carried out by the mechanism of the removable lever 5.

The unwinding of the threads from the bobbins 8, their release during the stretching of the loops with the gates and the tight tightening of the stitches are carried out by the thread guide mechanism.

In the case of sewing blocks on the root material (for example, gauze), it is fed from the bobbin 7 through the gauze loop b. After the end of sewing of the block, this mechanism makes a swinging movement up and down, pulling out a supply of gauze sufficient to form a loop necessary to obtain the valves after cutting the gauze. Thus, the notebooks that enter the swinging table are transported by it to the sewing machine, stitched with threads through the fold and remain there in a vertical position, gradually moving along the receiving table 10. The stitched blocks come out in the form of a fairly dense solid horizontal foot, which is supported from the back by a square eleven.

To separate the book blocks in the sewing process, a blank stitch is provided (there is no notebook for sewing). For the formation of a blank stitch, the notebook is not removed from the feeder magazine, all the actuators of the machine are idle. At the same time, such technological operations are carried out as the formation of a gauze loop when sewing with binding stitches and cutting the threads between the blocks.