Molding process principles and production of die-analysis

Bump indentation process is the use of the corresponding two yin, yang template, by pressure, in print embossed into the surface of a three-dimensional relief-like pattern, the processing effect is printed surface of a certain deformation.

    Indentation process is the use of cutting blades, and steel wire arranged in the template, under pressure, cut the roll-type printing process, the processing result is: both the printed surface deformation, another fracture.

    With the generated development and people's rising living standards, people goods, in addition to quality, the packaging requirements of products also increased. Molding process technology with its unique advantages, more and more widely being used in the processing of various types of printed surface to become non-print surface finishing technology, but a few.

    First, the molding process theory analysis

    1. Molded Dimensions

    Practice has proved that when the paper thickness increased, shear stress reduction; the other hand, shear stress increases. In fact, in the case of changing the thickness of paper, play a major role is not entirely the thickness of the paper, as well as molding the ratio of the size and thickness of paper, which changes the relationship shown that:

    Molded Dimensions / molding thickness trend with shear stress



 

    Note: 1,2,3,4 are printed in different thickness. Which 4> 3> 2> 1

    2. Pressure calculation

    In the molding process, due process and the requirements of as different, should generally be molded in advance calculated the force required in order to select and adjust the machine, and guide the molding process.

    Mold pressure F1 can be calculated: F1 = K * α * A

    Where: F1-molding the force required, α-molded in the shear stress per unit area, A-molding the actual separation of surface area, according to the print thickness and perimeter considered, K-molding process to consider the actual conditions and a series of technical factors affect the coefficient.

    Second, the production of die-

    Die-making, commonly known as row knife. Row refers to the so-called knife blades, steel wire, lining materials, according to the requirements of air, makes up the template of process operation. Cutting indentation production, quality assurance processed row knife key to the quality.

    1 plate material

    (1) bottom plate materials: including board, PVC board and steel

    ① board first asked board has a high hardness, resistant to pressure, to be uniform wooden board, cut neatly, elastic consistency. Put on a knife, wire elastic uniform. Full page without stress, thus cutting out the paper by force, not fracture, wear and tear on the knife small, extend die life, also requires good flexibility of wood, can ease due to bending knife board caused by stress is not appropriate, subsequently better solid blade, the cutting, they have some cushion, so that the blade is more durable. For production of die-birch and beech wood with. At present, Finland is the best quality wood board, wood, high hardness, good flexibility. Good die-cutting system of good quality. But it is expensive imported board, only for the high quality requirements of die. In the domestic product, the Shanghai board the best quality, even texture, pliability, high, white surface. Northeast board is not even wood, it applies only to the general corrugated boxes, medium-size box, the larger the curve graphics and other products. Plywood manufacturing die of high quality, light weight and templates. Therefore, commonly used in plywood floor boards, wood is commonly used in 18mm, 15mm birch board. Die products in general, with 18mm thick wood, cardboard or foam cutting, the use of 15mm thick wood. 20mm film and adhesive for the production of wood products, die, commonly used to clear waste of 12mm or 8mm version of the board.

    ② PVC board commonly used thickness 8mm, 5mm, 3mm, 3mm thick 18mm terms produced compound knife template, that is, the lower two layers of 3mm plastic board, the middle layer of 12mm board, three were later cut and positioning knife and then mounted on the rivet riveting line. As the cost cutting, loading knife difficult, resulting in high costs than wood die, coupled with PVC plastic cutting board will release toxic gases, metal parts and the body of the device there is a certain risk, not suitable for promotion.

    ③ thick plate of steel is not easy to cut, and so the high cost of steel plate is also used to make composite die. The upper and lower layers of 3mm thick steel sheet, in the middle of 12mm thick wood, although the cost of return, but made of die-strong, durable, can take multiple tool for the live version, because long-term change knife, the cost could be reduced, because of cutting quality is good, so you can use it to do.

    Die-life depends mainly on the number of tool changes, and the durability of different bottom plate is different.

    (2) used knives, wire

    ① steel wire: Steel wire indentation in the cutting process used to do with the indentation line. A round mouth lines and fast port line two. High-23mm, thickness 0.7mm.

    ② blades: the indentation in the cutting blades used to do with the cutting line. Blades are divided into single port, double-sided mouth, and other specifications, the general high-23.8mm, thickness 0.7mm. Used knives, wire Sweden, Austria, Japanese products, to meet all kinds of die-product processing, blades, there is a rigid material, in hard, soft three. Rigid blades, high hardness and wear resistance, but the flexibility of small, curved shape of small, so suitable for processing large, thick cardboard shapes simpler product processing; soft blades, low hardness, but with good elasticity, forming The curvature can be large, so suitable for processing small quantities, paper thin, the shape of complex products; the hardness of steel knife in between.

    Blades cut the length of the voltage to less splicing is appropriate, and generally not suitable for further forming voltage after the cut; steel wire after forming of the blades, the knife edge and the bottom should be perpendicular to each other, to keep the steel knife blade steel wire extension cord at every point on the same plane.

    (3) sticky rubber plug: it is the main steel knife edge on both sides of the template, using rubber elastic restoring force of the role and can be cutting edge after the separation of cardboard from the Ministry of launch. Its original height of 7mm, the rubber should be higher than the knife-edge 3mm ~ 5mm.

    Figure:



Schematic diagram of a sticky rubber plug, air liner material 2, 3 blades, rubber

    Rubber is generally made from synthetic polymer materials, elastic into hard, soft and neutral three, should be used depending on the circumstances a reasonable choice.

    (4) common processing tools

    ① Bending Machine: blades, steel wire shape of special tools. It can be blades, steel wire bent into any 30 degree arc of the arc and 90-degree angled. In order to expand the scope of use, easy to operate, equipped with such equipment commonly used in mold, there is a common bend angle and a set of common mold diameter round mold. (Each group about 20 species)

    ② sawing machine: sawing machine sawing of wood is a special tool. Both general and more drilling capabilities. Common saw blade thickness of 0.7mm and 1.07mm two. When used on cutting blades, steel wire and the thickness of the material being processed.

    ③ voltage wire machine: it is a special tool for cutting plate indentation. Main function is to steel wire, steel knife voltage into the required size.

    With the molding process of development, there has been a combination of die-machine system. A cutting template, cut steel wire, knives, corners, and round, oval shape features such as graphics.

    (5) at the end of mold materials

    Its main role is to make products bearing the line to clear, beautiful, wrinkle-free folded cracks, the shape accurately. Bottom mold materials commonly used kraft paper glued to the steel floor, kraft soft, easy to hand-draw slot, without pressure, indentation is not transparent. Currently, a large number of imports at the end of die line to enter the domestic market, such as a paste of multiple lines, outlet fast, convenient, full-line indentation, high anti-Indian forces. Supply of different manufacturers have different thick bottom mold line to provide its basic structure from the pressure line mode, positioning tape, protective film composition.

    2 graphics and layout

    (1) drawing

    Molded version of the system before the draft of the molded product of the black and white drawing out, that a single carton container of the expansion plan. General molding products will start drawing on a plane, with a pencil mark plate size, colors, pen mark product size, indentation of the line with other color pen mark (to avoid confusion). This map is plate, printing the basis on which the basis for molding processing. Their requirements straight lines and precise. Application of high-precision drawing table or plotter to draw.

    (2) molded version of the design

    Molded version of the structure depends on the product structure. Layout are: molding layout the size of the equipment should be used with the ability to match the specifications and work, both to ensure processing quality, but also good play equipment; determine the molded version of the species; choose the template materials and specifications; templates The Double column should be consistent with the Double column printing; working part of the plate should be located in a central location; lines, graphics transplant, required to ensure the accuracy of the product; layout knife to the straight line, longitudinal mode knife line at right angles to each other and with side parallel to the template, suitable for advertisement, broken to be aligned.

    To make the template on the blades, steel cutting wire with a good fit, product design, process of cutting should be considered:

    ① hole cutter wire should be used the entire line, the line should bend with rounded corners, to prevent the blades perpendicular to each other stitching.

    ② line the joints, should prevent sharp corners are like.



 

    ③ avoid waste several adjacent narrow side of the link, increasing the connections should be part of it together into one, so in the clearance of waste.



 

    ④ prevent multiple sharp corners in a row, on the cusp of reactive performance requirements can be changed round.

    ⑤ prevent sharp corners straight line ending in the middle of another paragraph, it would be difficult for solid knives, blades, easy to loose, and should be changed to reduce the cutting arc, or adaptive increase their encounter angle.

    3. Making templates

    Layout diagram in the system are advised to transfer to the plywood, the transfer of two ways, a hand-drawn, one is a photocopy. Hand-painted photographic accuracy than the end of some, but also trouble.

    (1) the production of bottom plate

    Bottom plate is made according to product design or sample request. On the plywood to the system along the lines of the graph line of inlaid knife slit. Pattern replication accuracy and caulking the molding process that affect the quality of the merits of the key.

    Bottom grooving There are many ways: lead weights row slot die cutter system; hand wood saw slot; slot machine industry cutting die plate; laser cutting die slot.

    (2) knife, the assembly line

    ① blades, steel wire cutting and forming voltage: according to design requirements, the knife used, line voltage cut forming the largest segment, and then processed into the required geometry.

    ② open connection point: In the mold, the opening is an essential connection point processes. Connection point is to open the mouth parts in the cutting edge of a small open mouth of a certain width, carton die in the process, so that part of the tray and waste in the cutting edges together after the still partial to take the next paper , the collection of paper and smooth. Make the connection point is to use special equipment to play the mouth edge machine, with the grinding wheel, open-side connection point, not use a hammer to open the connection point, causing damage to the knife line and take the corner, the connection point some glitches, bridge cutting knife position as vacant, do not open the connection point at this location.

    (3) emissions knife, wire

    Pai knife is based on product design specifications and style, good specification and planning and printing graphic proof is correct, you can start row knife operation. Lining material used in space based on different rows of knife operation is slightly different.

    The use of plywood for the lining material discharge air knife, blades, and steel wire should be perpendicular to the plane with the bottom plate embedded in the bottom plate saw cracks, gaps properly, should not appear in embedded or processing such as deformation or twisting phenomena.

    Air lead with metal blade row, the basis having certain technical requirements, with air lead directly to the knife-type mold plate fixed in the specified location, complete the row of knife operation, very similar to the movable type printing in the publishing operations, then asked staff to comfortable and flexible use of various types of air lead emissions in the work of the template can not be loose or channeling lines. System, especially in the row of various geometry, they need to ensure that graphics standard, but also to ensure an appropriate degree.

    Row of knife, should be blades, steel-wire interface according to row at the right location, the interface gap should be appropriate, not because of pressure occurs at the interface knife lines overlap or gap is too big is like. After discharge, template vertical and horizontal lines at right angles to each other, the edges parallel to each other, this forum will be smooth.

    (4) adhesive tape cutting

    Cutting the main strip in order to prevent the cutting knife, cutting indentation indentation line stuck in the paper, so take the paper smooth, elastic strips attached to the knife cutting line on both sides. Strip in the die cutting, will be deformation, impact cutting effect. If the knife away from the line too close to the lateral pressure generated by the strip pitch, when in the cutting edge of the paper is easy to nap; as far away from the cutting knife line, you will not achieve its own function. Generally from 1 to 2 mm is appropriate.

    (5) die at the end of the template produced

    Wash the steel bottom plate, and then paste it above the layer of insulating paper and then put a layer of carbon paper, then cover a layer of cardboard, and the power-indentation. According to Western blot, will die at the end of paper cut into strips, glued on both sides of the formation of indentation in the indentation groove. Usually die at the end of the die thickness is less than or equal to the thickness of the substrate, the indentation effect due to the arrangement direction of the indentation line and fiber orientation varies with fiber direction perpendicular to the line off after full indentation, therefore, engraved line, ruled the direction of the indentation line best narrow 0.1mm.

    (6) The cushion version

    Produced in the template, the template to be installed in the test cut on a cutting machine, in this process and try to cut the sample of local normal, and some do not cut through, then we should make this part of the pad version.

    Version with 0.05mm thick pad of paper glued to the bottom of the template, cutting to a high degree of compensation.