Carton die cutting problem and solution experts talk about suppliers

Sound from supplier two

The circular press die cutting machine has entered the country for more than 20 years. Due to the continuous updating of technology, it has become the main equipment for post-press carton processing. However, when using a circular press die cutting machine, there are certain limitations, some problems such as "inaccurate die-cutting indentation", "die-cutting fluffing", "explosive line" and other problems have appeared, affecting the circular press die Cutting machine use effect. The author's company has many years of experience in manufacturing and using circular press die cutting machines, and provides related solutions for some die cutting problems.

(I) Inaccurate position of die-cut indentation

Die-cut indentation is inaccurate, and is often caused by the performance level of the device and manufacturing accuracy. The paper feed system of the first-generation round-barrel hard-cutting machine made in China is a “chain manual feeding”, and the die-cutting accuracy is about 3-5 mm, which can only be adapted to the “fruit box” with low die-cutting accuracy; The semi-automatic die-cutting machines of the generation generally adopt the “feed-back reciprocating” feeding method, and the precision of the die-cutting equipment of the well-manufactured equipment can be controlled within ±1 mm. However, because the “soft-cut” technology is mostly used, there is an “incision”. The problem of "hairiness" (this problem will be described in detail in the following article); Domestic third-generation fully automatic round press die cutting machine not only greatly improves the automatic control technology, but also has greater manufacturing precision. The breakthrough, die-cutting accuracy can be controlled between l 0.5 mm, can meet the requirements of high-precision cartons, but the price of equipment has also been improved a lot. The fourth-generation improved automatic round-press die cutting machine currently being developed has been used in large-scale promotion. In the paper-feeding system, the “forward-feeding” technology has been adopted, which not only improves the accuracy and speed of paper feeding, but also expands. The scope of use can meet the requirements of various non-standard or problematic paperboards, such as "multifaced paperboard", "ultra-thin paperboard" and "bent cardboard". The cutting speed can reach 160/min, and the precision of die-cutting can be Controls between 0.5 mm and 0.5 mm. (See Table 1)

Accuracy and efficiency are important indicators for measuring circular die-cutting machines. High-precision cartons are required for die-cutting machines with excellent performance, high-quality cardboard and skilled operating techniques. Carton packaging manufacturers can choose the corresponding die-cutting equipment according to the requirements of the product.

(B) Die-cutting burst line problem

When the circular press die cutting machine is in use, because of the quality problem of the paperboard, it is easy to have a "burst problem". The explosion usually occurs in the parallel direction of the corrugated fiber, and the "corona" does not occur in the vertical direction of the corrugated fiber, mainly due to the pressure line. The choice of height and width is unreasonable. For the die plate used in the round press die cutting machine, the width of the press line should be selected according to the thickness and quality of the paperboard. If the height of the indentation line is low, the indentation line is not clear; if the indentation line is of high height, it is easy to cause bursting. It can generally be selected based on the following empirical formula:

Hard cutting: Die cutter height - 1/2 (cardboard thickness) = indentation line height

The heights of the soft-cut die cutters and indentation lines currently on the market are listed in Table 2. Types of indentation lines include "bulk line", "steel wire", and "nylon indentation line". When the requirement of die-cutting cardboard is high, the “bulk line” type indentation line is used, but it is easy to produce the phenomenon of “explosive line”, and rubber pressure line guards can be inserted on both sides of the indentation line to prevent the occurrence of burst line. The role of; When the cardboard quality is relatively poor, it is recommended to use "nylon indentation line", this indentation line has a simple installation, low price, height adjustable characteristics, to meet the production needs.

(c) Problems with hair cutting in die cutting

The round press hard cutting machine does not have the problem of hairline cuts, and the incision is smooth. However, due to the "hard bumping" of the plane of the die cutter and the roller, the cutting rate is up to 90%, and it is easy to damage the cardboard during the scrapping. Usually only 2-3 million times. When the edge of the knife is cut, there will be a problem with the haircut, which can be solved by trimming the cutting edge with a fine file.

The common haircut phenomenon occurs on the circular press die cutting machine. Because the soft cutting machine must use the "serrated knife", the knife edge is serrated, so the edge of the incision is serrated and there is a problem of hairiness in the incision. The solution to this problem is It is necessary to use "single sided edge" first, because the usual die cutters are mostly "double sided edges". When installing on the stencil, use the "single-edged" die cutter and install the edged side on one side of the waste paper so that the finished cut is smooth, even after the blade is passivated. There is no problem with hair cuts. Because the single-edged die cutter is relatively expensive, it can only be used for products that require smooth die cuts. When making a stencil, the calculated size should also have a corresponding change. The circumference is the thickness of the surrounding die cutter.

In the domestic market, there are many manufacturers of circular presses and die cutting machines, and there are many differences in the grades of products, and the function configuration is also varied. Because the "hard cutter" itself has a low tool life (only 20,000-30,000 times), the cut-off rate is at most 90%, and the problem of difficult scrapping is relatively small. The domestically-manufactured third-generation round-circle-soft mold die cutting machine has the functions of automatic compensation of line speed, soft roll repair, moving and moving, and push-plate automatic feeding. The die-cutting accuracy can generally be within ±1 mm. About 100 pieces of paper are fed per minute, and the life of the tool plate is more than 600,000 times. It can meet the requirements of the general corrugated box packaging industry. However, due to the complexity of the tool plate manufacturing and the high cost, it can not meet the requirements of carton products that are not mass-produced. With the use of purchased knife products, centralized manufacturing can reduce the purchase cost.

The above is the author's point of view on the use of die-cutting machines, for the use of personnel engaged in related work, and also welcomes the relevant persons and I for experience and technology exchanges.