Indentation tools are called steel wire, indentation line or beer line. Steel wire materials must have characteristics such as wear resistance and bending. According to different indentation needs, the shape of the steel wire is single head line, double head line, round head line, flat head line and pointed line.
In corrugated box production, indented steel wire is a very important production component in carton forming. How to choose it?
Pay attention to the thickness of the indentation line
1. The width of the kerf (laser slit) on the diecut should be such that the indentation steel wire is tightly fitted, and at least the indentation steel wire can not be pulled out with bare hands.
2. In laser die-cutting plates, high-grade inserts are usually used to meet users' requirements for service life and bending performance. The thickness of high-grade inserts has strict tolerances. For example, the thickness tolerance of Sandvik's 0.71mm inserts is ±0.015mm. Laser slits are very stable and strong when combined with such thickness tolerances. The thickness of commonly used indentation lines is shown in Table 1.
3. If the indentation steel wire with large thickness tolerance is used (thickness tolerance of many low-grade indentation steel wire is ±0.06mm-±0.10mm), the indentation steel wire installed on the die-cut plate will be reversed when it is compressed. On one side, this brings a series of problems:
The position of the indentation deviates from the design position;
Paper box, carton shape change;
Sticking machine box;
At the bottom of the template, the strips are opened and displaced;
Indentation height is reduced, indentation is too shallow;
Indentation steel wire looses and even falls off.
Note the actual height of the indentation steel wire
In actual production, we need to understand the true thickness of the indented steel wire, not the thickness of the mark. The actual thickness can be measured with a micrometer.
The height of the indented steel wire is calculated from the height of the insert and the thickness of the material being die cut. The die-cut material is divided into cardboard, corrugated paper, plastic, and other types, and their thickness is not the same, so the height of the indentation steel wire is also finer. Some commonly used indentation steel wire heights can be found in Table 1.
Indentation line height = (die cutter height - thickness of die cut material) ± correction value
The correction is based on different paper quality. The cardboard used for die-cutting and paperboard will be different: the longer paper fibers are more resistant to pull, and the higher-strength creasing steel wire can be used; while the short-fiber paper is relatively brittle, it needs to be reduced accordingly. The height of the indentation steel wire.
However, we found in the production practice that although the height of the indentation steel wire installed on the die-cut plate is strictly calculated and corrected (the height and thickness of the ink-jet printing by the manufacturer prior to shipment from the indentation steel wire), However, the indentation is always not in place, and often this batch of deep and the next batch of shallow situations will occur. It is necessary to constantly adjust in the die-cutting production, and it is still inconsequential. What is the reason? According to investigations, many of them are caused by the fact that the actual height of the indented steel wire is far from the mark height. It is recommended to measure with a micrometer to see if there is a gap between the marked height of the indented steel wire and the actual height of the used die-cut version. How much worse?
The 0.71mm indentation steel wire used for the paperboard indentation shall have a height of at least one file per 0.10mm. When the difference between the actual height and the mark height exceeds 0.01mm, it indicates that another specification is required. Indentation of steel wire, it is not possible to press out the calculated or desired indentation height and indentation effect using the steel wire now used.
How to choose indentation steel wire
When the effect of indentation in production is not satisfactory, the first thing to do is to confirm the actual height and thickness of the indented steel wire, and to see how far it differs from the mark's specification, otherwise any other effort Fundamentally solve the problem.
Secondly, a good indentation steel wire requires that the indentation of the round head be symmetrical and centered. B. Put the two creasing steel wires together and compare the size of the white part of the indentation end. It can be easily judged whether it is symmetrical or not. .
Thirdly, the round outline of the indentation line is required to be smooth, and the transition from both sides to the top should be uniform. Otherwise, the high-quality printing surface will lose its original flatness and gloss after the indentation.
To figure out the points mentioned above, when confronted with the quality problem of indentation, we only have to look at the magnifying glass and take a closer look and we will find that many of the problems encountered on a daily basis can be solved in such a simple way. And avoid it.
Selection of Indentation Steel Wire in Round Die Cutting
Round die cutting is similar to flat die cutting in the selection of indentation steel wire. The round press circle has a larger retractable space than the die cut, making it easier to select the height of the indented steel wire.
Normally, the horizontal indentation steel wire is slightly higher than the circumferential direction. When calculating the indentation steel wire, it is necessary to take into account the depth of the blade cutting into the bottom roller, the blade is usually cut to the depth of the bottom roller 2. Omm-2.5mm (Uni knife is 1mm-1.5mm). The use of indentation ridges can fully prevent the occurrence of bursts, laser head lines, and crosshairs, and can improve the efficiency of platemaking while improving the indentation effect.
What needs to be reminded again is that the indentation steel wire is crucial for the control of the forming precision of the box piece. The indented steel wire also plays the role of controlling the traveling speed after the box piece is detached from the paper feeding wheel.
(Wang Liqun)
Ningbo XISXI E-commerce Co., Ltd , https://www.xisxipetsupplies.com