Carton die cutting problem and solution experts talk about the carton factory

Sound from carton factory II

People are increasingly demanding packaging products. Cartons packaging requires not only bright colors, but also requires generous design, clear lines, and smooth folding. The importance of die-cutting technology is also gradually emerging. The quality of the die-cutting process is then affected. The problem arises. The author will make some brief introductions to the problems encountered in actual production.

(a) Cardboard shift, tilt

Due to improper adjustment of the gap in the entrance section of the die-cutting machine, the gap is too large and the force of biting the paper is not sufficient when entering the branch. The formation of skewness should be based on different types of cardboard, and the feed pressure should be properly adjusted. The aging and wear of the feeding wheel causes unevenness in various parts of the feeding wheel. When the cardboard is conveyed, the gaps on both sides are inconsistent, so that the feeding is skewed, and a cloth tape can be used to wrap the feeding wheel at a low position. Temporary To solve this problem, as long-term considerations should be promptly replaced feeding wheel. Improper use of the traction wheel, improper adjustment of the traction wheel clearance will also cause the cardboard to be skewed in the process of transmission, and to properly adjust the position and clearance of the traction wheel. The gears of the machine are worn out due to wear. Check and maintain the equipment regularly, and replace the parts when the wear is serious.

(B) Pressure burst

Because the moisture content of the paperboard is too low, causing the pressure line to burst, this phenomenon occurs more often in the winter. Since the weather in winter is dry and cold, the relative humidity in the air is low, which will directly affect the moisture content of the paperboard and cause the board to break after the pressure line. The general practice is to require the base paper manufacturer to control the moisture content of the base paper as much as possible (between 8% and 10%) in the winter. When making corrugated paperboard, pack less dryer cylinders to speed up the vehicle speed to reduce the moisture loss from the paperboard; After the timely production of die cutting, not easy to store for too long, reduce the relative humidity on the moisture content of the cardboard, for low moisture content of the paperboard, you can smear water on the cardboard to reduce the burst phenomenon. Crimping knife is too narrow or too high caused by the pressure line burst, should be based on the screening thickness of the cardboard, in the production of mold selection of different thickness, height of the knife; in the installation of the mold, the various parts of the fixing screw is not locked, Causes the mold to loosen, can also form the popping phenomenon, so should check whether the screw locks after the mold installment; Also must pay attention to is the mold use time is long, the pressure knife will loosen, causes the pressure knife to bounce in the cutting process, causes Cardboard pressure line burst, should always check the mold and found that the knife has to be repaired or re-made in time. The unevenness of the pad causes the pressure line to burst. Due to the long use of the pad, and the different specifications of the cardboard box being die-cut, the wear degree of the pad will be different, resulting in uneven phenomenon, ie, in the same setting. Under the parameters, some places are under heavy pressure and some places are under pressure. The method to solve this problem is to often change the position of each pad, so that the wear degree in the process of using as close as possible, some machines with automatic grinding function, that is, according to the degree of wear of the pad automatically trimming, Keep the pad flat. The position of the sponge pad of the knife is not proper. When the burst phenomenon occurs, the sponge pad can be used next to the knife of the die to help destroy the corrugation at the cardboard line to solve the crack phenomenon, but the sponge used The pad should not be too soft and should use its own harder bead. Deformation and damage to the tool's crimper can also cause pressure lines to burst, and the pressure knife should be replaced in time.

(c) There is tearing on the edge of the cardboard and the knife edge is not straight

The long use time of the die cutter results in the bluntness of the knife edge. When the cut paper board is formed, it is cut continuously. After the scrap paper is cut, tearing occurs and the tool must be replaced in time. The splicing of the dies and knives is not good, and tearing may also occur. It is required that the mold makers pay special attention when installing the splicing tools. The sponge pad is close to the cutter. During the die-cutting process, the sponge pad is pressed to generate a pressing force around it. If the tool is close to the cutter, the cutter bending phenomenon will occur, which will cause the die-cut cardboard edge to be bent and not straight, so When sticking the sponge pad, it should keep a certain distance with the cutter, generally about 2 ~ 3mm.

(four) die cutting size is not the same size

This problem occurs in the round press die cutting machine. When the pad on the die cutting machine is worn for a long time, its circumference diameter becomes smaller, which directly affects the circumference of the die plate circumference and the pad circumference, and the machine operation is affected. When there is no synchronization between the upper and lower, the formation of the speed difference causes the dimensions of the front and rear molds to be large and small. Installing a variable speed motor on the machine table to adjust the speed of the pad roller can improve this problem, but it must rely on the operator's technology to make the correct adjustment. Even if such an adjustment is made, it is difficult to ensure that the front and rear molds are of the same size. Because in most cases, the pads wear differently throughout. In addition to this, it is also possible to make the rear mold slightly longer to compensate for the difference in size, but the problem of dimensional accuracy of round-bore die cutting cannot be fundamentally completely solved. At present, there is a product called “Die-cut Equalizer” that improves this problem by changing the surface speed of the pad, but the price is relatively expensive.

(Text / Ling Jie)