Postpress Technology 1000 (628-642)

628. What are the requirements for opening operations?
Answer: The requirements for the opening operation are as follows:
(1) When opening loose pages, the specification of the official post shall prevail, and the page number of the adjacent signature shall be accurately matched in place;
(2) When opening a chart, it should be proportional to the small margin of the text;
(3) When opening the cover material, it is necessary to accurately calculate the width of the spine, the trim of the burrs, and the uniformity of the four sides of the book frame and the book according to the specifications of the book;
(4) When opening hardcover book shell paper, all knife is used, no outer knife is needed to ensure that the cardboard does not have slopes and irregularities after cutting;
(5) When the hard-packing material is to be opened, a reasonable calculation shall be made according to the size of the specification. It is necessary to have a qualified size, save materials, and conduct scientific and rational material processing.

629. What are the format specifications for International Standard Type A?
A: The international standard A-type paper format specifications are 889mm × 1240mm and 900mm × 1280mm two.

630.A type paper commonly used in the number of cutting specifications which?
Answer: As shown in Table 1, specifications are all length × width.
631.B-type paper commonly used in the number of crop specifications?
Answer: As shown in Table 2, the specifications are all length × width.

632. What is the sizing at the time of cutting?
Answer: The sizing at the time of cutting is based on the number of materials to be opened. The more the number of openings, the more sizing. Under normal circumstances, the minimum number of cuts, including light edges, is 4mm. With the increase in the number of cuts and the increase in the number of cuts, cuts naturally increase.

633.How to unload a knife when using a common cutter?
A: When unloading the knife, the first step is to lower the blade to the lowest position to make it come into contact with the blade, stop the machine at the same time and stop all activities of the brake; in the second step, loosen the bolts that are exposed on the outside of the blade and insert the blade. After gently touching the blade, unscrew the bolt to raise the knife holder (cartridge or blade) to the original position. In the third step, use both hands to pinch the blade back or both ends of the remaining blade and take it out. After inserting the knife box, the unloading operation is completed when the tool is changed.

634. What are the forms of sharpening machine?
A: There are two types of sharpening machines, flat and arc.

635. Which type of sharpening is better and why?
A: The sharpening form of the flat-type sharpening machine is better, because the α-angle of the blade it grinds is a straight line, and the bearing capacity is large, which can prolong the service life of the blade and increase the cutting times of the blade.

636. What are the disadvantages of arc sharpening?
A: The blade milled by the arc-type grinding machine has a certain degree of curvature in the slope, which affects the accuracy of the blade α angle, resulting in a decrease in the shear resistance, resulting in premature wear of the blade, shortening the service life, and reducing the number of cutting operations.

637. How to replace a new blade?
A: When replacing a new blade or a re-polished blade, first check whether the angle α of the blade meets the cutting force of the work piece to be cut, then wipe the blade with the cloth from top to bottom, and do not wipe it against or along the blade. Wipe to avoid injury. Attention should be paid when replacing: 1 Do not touch the blade with any hard object to ensure the sharpness of the blade; 2 The height of the tool change should be appropriate so that the paper can be cut without touching the blade to the paper; 3 Tool change Afterwards, a detailed examination must be carried out. If irregularities are found and adjustments are made in time, the inspections are correct and they must be cut several times before cutting.

638. How much is the contact depth between the cutter blade and the blade plate?
A: There are two situations when the cutter blade and the blade are in contact when cutting: for the new blade, the contact depth of the cutter should be 0.2~0.5mm; for the blade that has worn out the gap for a while The plate can expand the cutter contact depth range to 1~1.5mm, which is not dependent on the cutter paper and the cut smoothness.

639. What is the role of the blade?
A: The knife blade is also called knife blade. It is installed on the cutter plate under the cutter. When the cutter blade cuts under pressure, the blade plate will hold the pad and it will complete the cutting of the paper without cutting the blade. Worn cushion knife function.

640. What kind of material is made of the blade?
A: The material used to make the blade is initially made of wood, such as eucalyptus; resin materials such as nylon plates, plastic plates, etc. are now used; it is also made of bakelite. However, regardless of the kind, the hardness and elasticity should meet the requirements of the cutting blade.

641. What are the precautions for using the blade?
Answer: 1 The blade plate placed in the groove should be flush with the surface of the paper cutter, and it should not be protruded or recessed. When it protrudes, the paper frame cannot be pushed in, which will affect the quality of the cutting; when the groove is recessed, the paper frame will be easily concaved. The surface of the groove is blocked or a convex indentation appears below the finished paper box; 2 the blade plate needs to fill the groove and have no gap with the groove to ensure that the blade plate is not moved arbitrarily; 3 the blade plate used should be flat Straight, flat and warped.

642. What are the ways of folding?
A: Although there are various folding styles, they are all based on the layout of the page layout, ie, how the typesetting should be folded, and the typesetting is based on the binding style of the books and the folding mechanism of the machine, such as paperback and horseback riding. Ordering, there are scattered pages and no loose inserts.

- "Printing Technology - Publishing Commercial Printing"