Major Solutions to Common Faults of Die Cutting Machines

Different analysis and solutions are provided for common problems such as "broken lines" and "dark lines" on corrugated die cutting machines, as well as issues like fuzziness and low cutting precision.

During the daily production and use of die cutting machines, various types of faults are often encountered, which can have a certain impact on production. The following are the analysis and solutions for several common faults of die cutting machines:

1. Problem: "Broken lines" refer to the rupture or partial rupture of paper fibers caused by excessive pressure in die cutting, exceeding the limit of paper fiber tolerance. "Dark lines" are unintended embossed lines, usually caused by inappropriate selection of die cutting plate and creasing rules, improper adjustment of die cutting pressure, poor paper quality, inconsistency between the paper fiber direction and the cutting direction of the die cutting plate, and decreased flexibility due to low moisture content of the paper.

Solution: Select an appropriate die cutting plate and adjust the die cutting pressure properly. Before die cutting, let the printed material sit in the workshop for a period of time to increase the relative humidity of the workshop environment. The best method is to reduce the height of the creasing rule by 0.1~0.2mm. The specific reduction depends on the basis weight of the paper. For paper with a basis weight above 350g/m2, the height of the creasing rule should be reduced by 0.2mm, while for paper with a basis weight below 350g/m2, it is recommended to reduce it by 0.1mm.

2. Problem: During die cutting, there are often issues such as rough and fuzzy edges, especially near the crease line. This is caused by the tension exerted on the paper by the rubber strip and creasing rule on the die cutting plate during die cutting and creasing, causing the paper to be pulled and broken before being completely cut, resulting in fuzzy edges.

Solution: First, choose different types of die cutting blades according to the paper. Die cutting blades include straight blades and cross blades, which also have different heights. The different patterns and heights formed by the blades directly affect the quality of die cutting and the service life of the blades. For avoiding fuzziness, straight blades are better than cross blades. For the service life, shorter blades are better than taller ones. When die cutting laminated paper, it is recommended to use straight blades with shorter heights, and the blades should be polished. It is better not to use the one-step molding process of embossing and debossing, as excessive pressure will greatly affect die cutting. For processing regular cardboard, shorter blades should be used, and the pattern of the blades should be determined based on the quality of the paper fibers.

3. Problem: Low cutting precision of the die cutting machine.

Reason: The low cutting precision is caused by issues with the die cutting version and the printed materials. Handmade die cutting plates have larger errors, and the difference in the working environment between die cutting and the printing process can cause paper deformation and inaccurate positioning of the die cutting pressure mark. This is especially severe after varnishing or film lamination, which affects the die cutting precision.

Solution: Choose advanced die cutting plate making technology to improve the precision of the die cutting plate. Try to ensure that die cutting and the printing process are carried out in the same working environment, or ensure the uniformity of the working environment (such as temperature and relative humidity). Pre-treat the paper after varnishing or film lamination to minimize the impact of paper deformation on the die cutting precision.