Analysis and treatment of deformation phenomenon i

Analysis and treatment of deformation phenomenon in the production of flat die-cutting plate

die cutting indentation process is a process of rolling and cutting printed matter into shape under the action of pressure by using the template arranged by steel knife and steel wire. Its processing effect is that the surface of printed matter has both deformation (indentation) and fission (die cutting)

the research, development and utilization of basic common technologies and technical standards in the polymer surface material industry promote the production of central die-cutting plate, commonly known as knife arrangement, which refers to the technological operation process of assembling steel knives, steel wires, hollow lining materials, etc. into a die-cutting plate according to the specified requirements. The general process of making die-cutting plate is as follows:

draw the outline of die-cutting plate → cut the base plate → steel knife and steel wire cutting and forming → combination and assembly → open the connection point → paste sponge adhesive strip → try to cut the pad plate → make the impression bottom mold → try die-cutting and sign samples

first, draw the outline of die-cutting plate

first, design the layout of die-cutting plate according to the requirements. The tasks of layout design include: (1) determine the size of the layout, It should match the specification and working capacity of the selected equipment; (2) Determine the type of die cutting plate; (3) Select the material and specification of the die cutting plate. The designed layout should meet the following requirements, that is, the space of the die-cutting plate should be consistent with the printing space; The working part should be in the center of the die-cutting plate; The transplantation of lines and graphics should ensure the accuracy required by the product; The cutting lines of the layout should be straight, and the vertical and horizontal cutting lines should be at right angles to each other and parallel to the side of the die-cutting plate; Align the broken knife and thread

the outline drawing of the die-cutting plate is the unfolding drawing of the whole plate product, and it is the first key link in the production of the die-cutting plate. If the printing adopts the whole page jigsaw system, the outline of the die-cutting plate can be directly output in the printing plate making process, which can effectively ensure the unity of the printing plate and the die-cutting plate. If the printing adopts manual film composition, it is necessary to draw the outline of the die-cutting plate according to the actual size of the printing sample layout. In the drawing process, in order to ensure that the die-cutting plate does not scatter during the plate making process, several "bridges" should be left in the large-area closed graphic part. The bridge width can be designed as 3 ~ 6mm for small plates and 8 ~ 9mm for large plates. In order to make the steel knife and steel wire of the die-cutting plate have better die-cutting adaptability, the following problems should be paid attention to in product design and layout drawing:

1. The knife line of slotting and opening should adopt the whole line as far as possible, and the corner of the line should be rounded to prevent the splicing of mutually perpendicular steel knives

2. Sharp corners shall be prevented at the joint of the two lines

3. Avoid the connection of multiple adjacent narrow waste edges, and increase the connection part to make it connected into a piece, which is convenient for waste removal

4. Prevent multiple continuous sharp corners. Sharp corners without functional requirements can be changed into rounded corners

5. Prevent the sharp corner line from cutting off the middle section of another straight line, which will make it difficult to fix the knife, easy to loosen the steel knife, and reduce the die-cutting suitability. It should be changed to arc or increase its encounter angle

II. Cutting template (slotting)

the commonly used blank lining materials (base plate) of die-cutting template include metal blank lining materials and non-metallic blank materials; Among them, multilayer plywood is used most, and the thickness of plywood is generally 18 ~ 20 mm. The cutting of base plate (hollow lining material) mainly includes sawing machine cutting, laser cutting and other methods

sawing machine cutting is the main method for small and medium-sized enterprises to process die-cutting plates by themselves at present. The work of sawing machine is to use the up and down movement of special saw blade to process the constant tension from empty plate to full plate on the bottom plate. It is required to produce a narrow groove that can be loaded with steel knife and steel wire. The thickness of saw blade is equal to the thickness of steel knife and steel wire at the corresponding position. The sawing machine is equipped with an electric drill, which can drill holes on the bottom plate. After drilling, the saw blade will pass through the bottom plate and then cut. The current sawing machines have rich specifications and complete functions according to the occasions of use and the types of plate making. Some sawing machines are equipped with a dust suction system, which can automatically collect the sawdust cut by sawing. The saw blades can be clamped electrically. Some large layout sawing machines are also equipped with an air flotation system on the workbench. It can make the sawing of large layout light and flexible. In recent years, CAD/CAM technology has also been applied to the production of die cutting plates. Its principle is to use CAD/CAM technology and computer control technology to control the sawing machine to complete cutting, and the slotting quality has been greatly improved

laser cutting is carried out on a computer-controlled laser cutting machine. It uses laser as energy to cut the substrate material through the high temperature generated by laser. For laser cutting, first of all, you need to input the whole die cutting outline into the computer, and the computer controls the movement of the base plate, and then cut it with laser. However, many parameters are needed in the cutting process, such as material quality parameters, plate thickness, laser output power, type and pressure of auxiliary gas, diameter and caliber of nozzle, distance gap between material and nozzle, focal length of lens, position of focus and cutting speed. Therefore, in actual production, it is extremely important to learn from previous experience to determine the processing effect. The main disadvantage of laser cutting is that the laser cutting machine is expensive and the cutting cost is high, which makes the production cost of die-cutting plate higher. Therefore, this kind of die-cutting plate is generally produced by professional manufacturers and directly customized by users

III. forming and combination of steel knife and steel wire

due to the decline of performance, the cutting and forming processing of steel knife and steel wire should be carried out first, that is, the steel knife and steel wire should be cut and bent into corresponding length and shape according to the expected increase speed will gradually slow down. There are generally two methods to complete this process: manual single machine forming and automatic bending machine forming

the special equipment for manual single machine forming and processing mainly includes blade cutting machine, blade forming machine (machete machine), blade punching machine (bridge cutter), blade corner cutting machine, etc. Among them, the blade cutting machine is used for cutting the length of steel knife and steel wire; Blade forming machine (machete machine) is used for precise forming of arc or angle of steel knife and steel wire; Blade punching machine (bridge cutting machine) is used for punching knives and lines across the bridge; The blade corner cutting machine is used for cutting corners of steel knives at the intersection of knives and lines (to ensure effective cutting). This processing method is slow, low production efficiency, unable to process fine and complex graphics, poor repeatability, and highly dependent on manual proficiency and technical level; However, the cost is relatively low, which is suitable for the processing of die-cutting plates with low quality and tight construction period

(to be continued)