Application and key points analysis of die cutting

Corrugated box die cutting indentation process application and key points analysis

Abstract: This paper mainly discusses the application and processing points of corrugated box die cutting indentation process

key words: die cutting indentation typesetting indentation die line

die cutting indentation is an indispensable process in corrugated box processing. After die cutting and indentation, the appearance quality and market competitiveness of cartons have been greatly improved

the main technological process of die-cutting indentation is pneumatic units T, kg, N, kn, G, LB: product design → die-cutting tool processing → typesetting → loading and pad → die-cutting indentation → finishing → finished products

1. product design

when designing corrugated boxes, it is necessary to accurately calculate the internal dimensions of the packaging, and try to use rounded corners at the corners of the lines to prevent sharp corners, which is conducive to knife arrangement; Avoid connecting multiple adjacent narrow edges to facilitate waste removal. After the specifications of each part of the corrugated box are determined, the method of proofing and trial molding is adopted to check the rationality of the specifications and the artistry of the appearance, and then formal plate making is carried out

2. tool selection and processing

the tools used for die cutting are called die cutting knives, also known as steel knives, beer knives, etc; The tool used for indentation is called indentation line, also known as steel wire, beer wire, etc. Die cutting knives and indentation lines are made by professional factories. Users only need to select them according to requirements. The height of the common die cutter is 23.8 mm and the thickness is 0.7 mm

thickness D and height h of corrugated box indentation line:

D ≥ C

H = H-C

C - thickness of corrugated board after compaction

h - height of die cutter

the cutting edge of the die-cutting indentation tool should have a certain hardness, and the tool should be specific and tough. It can be bent into any complex shape to meet the needs of the complex shape of the die-cutting indentation product. The thicker the blade, the harder it is to bend; The higher the blade, the greater the force required to bend. For products with extremely precise and complex shapes, thinner blades can bring many conveniences

according to the requirements of the product, select tools with different hardness and shapes, and bend the tools into the required shape with bending machine and other equipment. The die of the bending machine with good design can avoid incorrect pressure on the deformation of the blade

the blade should have a certain degree of bending plasticity. The blade can neither be like a spring nor deform under a little pressure. Good plasticity should be that the blade bends into a certain shape and rebounds slightly

when installing the blade into the slotted formwork, it should be properly tightened. The blade can be embedded by gently tapping with a plate making hammer. The thickness of the blade and the width of the sawing gap should be controlled within a certain tolerance range. The knife back with an inclined plane allows the blade to be easily installed into the template

the die of the blade cutting machine should have precise perpendicularity, which can ensure that each cutting end is perpendicular to the blade

drum type die cutting indentation tools are divided into assembled and integral types. The assembled die cutting tools and indentation lines are assembled on the die cutting indentation drum, and the integral die cutting tools and indentation lines are integrated with the drum

the assembled die-cutting indentation roller is easy to assemble and flexible to replace products: the manufacturing of the integral die-cutting indentation roller is complex, and the whole roller should be replaced when replacing the former expensive products, but this method has high die-cutting indentation precision and fast speed

3. Holding version

typesetting is also known as knife arrangement. Before typesetting, bend the cutter into the required shape according to the shape of the die-cutting indentation product, and fix the cutter in the frame with blank lining material to make a die-cutting indentation plate. The lining materials include lead, wood, fiber plastic board and steel board

lead lining materials include lead blocks and lead bars. Die cutting indentation plates made of lead blocks and lead bars have low dimensional accuracy and are easy to scatter

the wood board lining material generally adopts multilayer plywood with a thickness of about 18mm. This material is affected by the changes of ambient temperature and humidity. 6. After the pressure test of the pipeline, it is large, easy to deform, and the size is unstable, which affects the accuracy of die-cutting indentation

fiber plastic board is not affected by temperature and humidity changes, and has good dimensional stability. It is a good die-cutting indentation plate, which requires special equipment for processing, and the cost is high

steel die cutting indentation plate has high precision, no deformation and complex processing

when typesetting, first design the die cutting layout according to the product. The size of the layout should match the specification and working capacity of the selected equipment; The position of the die-cutting plate should be consistent with the printing position; The working part should be in the center of the die-cutting plate; 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

the outline drawing of the die-cutting plate is the unfolding drawing of the whole plate product. If the printing adopts the whole page assembly system, the outline drawing of the die-cutting plate can be directly output in the printing and plate making 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 ~ 6 mm for small plates and 8 ~ 9 mm for large plates

when designing the layout, the cutting line of slotting and opening should be 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; Sharp corners shall be prevented at the joint of two lines; 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; Prevent continuous multiple sharp corners. Sharp corners without functional requirements can be changed into rounded corners; Prevent the sharp corner line from cutting off the middle section of another straight line, which will make it difficult to fix the knife, the steel knife is easy to loosen, and reduce the die cutting suitability. It should be changed to arc or increase the included angle

in the process of plate making, it is also necessary to open the connection point. The connection point is to open a small opening with a certain width at the edge of the die-cutting knife. During the die-cutting process, the waste edges that can be hot pressed, welded, bonded, reinforced, machined, etc. are still partially connected to the whole print sheet after die-cutting without being scattered, which is convenient for paper feeding. The connection point is opened with a knife line punch, which is ground with a grinding wheel. Do not open the connection point with a hammer and chisel, otherwise the knife line will be damaged and burrs will be generated in the connection part. The connection point is usually placed in the concealed place of the formed product to avoid affecting the appearance of the finished product

do not open the connection point at the bridge crossing position, and try to avoid opening the connection point at the gluing position. Generally speaking, the width of the connection point of corrugated board is corrugated paper, and the actual thickness of the board plus 0.2mm is about 1 ~ 3mm. (to be continued)