Quality requirements and inspection methods of the

St methods for post press finishing

quality requirements and test methods for thread sewing cy/t7

approved by the publication administration of the people's Republic of China on July 1, 1991 and implemented on October 1, 1991

1 theme content

this standard specifies the quality requirements and inspection methods of book and magazine sewing

2 reference standard

gb 9851 printing technical terms

gb 788 book and magazine format and size

3 classification

3.1 flat lock

3.1.1 manual flat lock

3.1.2 machine flat lock

3.2 cross lock

3.2.1 manual cross lock

3.2.2 machine cross lock

4 quality requirements

4.1 see Table 1 for the sewing distance and number of stitches

Table 1 distance between the upper and lower needle positions of the folio and the upper and lower incisions (mm) needle number needle group 8 open 20-30 8-10 4-5 16 open 20-30 6-8 3-4 32 open 154-62-364 open and below 10-1542

needle positions should be evenly distributed on the last crease line of the book post

4.2 requirements for sewing

4.2.1 the book blocks after sewing are arranged correctly and neatly, without damage, page falling and oil dirt. Jinan assaying drop hammer impact testing machine features

the publication administration of the people's Republic of China-01 approved the implementation of

4.2.2 the eyelets of the sewing needle are smooth, and there are no holes and cracked stickers

4.2.3 the lock line shall be tightened and loosened properly, and the thickness of the locked books and stickers shall be basically the same, flat and neat, so as to achieve the purpose of energy conservation and emission reduction. There is no large volume post and crooked page, and the shrinking post shall not exceed

2.5mm. No needle leakage, angle folding, wire breakage and coil

4.2.4 the book block after sewing has no independent new company, which will be given greater freedom to pierce the ring lining

4.3 thread specification and sewing form

4.3.1 use 42 or 60 white wax tower threads with 4 or 6 strands, or nylon threads of the same specification

4.3.2 sewing form: cross lock is used when the size of the book sticker paper is less than 4O grams, and flat lock or cross lock is used when it is more than 40 grams

5 test method

5.1 measurement method

check the setting distance and shrinking with a millimeter ruler

5.2 visual inspection method

professional technicians conduct self-test and inspect the product quality according to the standard requirements

additional notes:

this standard is proposed and centralized by the publishing administration of the people's Republic of China

this standard is drafted by China Printing Corporation

the drafters of this standard are Wang huaizhu and Shi Qunfang