Study on the Life of Carton Printing Slotter Blades

Carton printing slotting machine, molding machine and various printing die cutting slots and other multi-functional joint machine. With high quality and high education, compact structure and other characteristics, is widely used by carton packaging companies. Slotting knife is one of the necessary tools. Its service life has a direct impact on carton slotting quality and manufacturing cost. It is one of the problems that need to be improved in quality management and cost management of similar companies.

In today's fierce market competition with quality and price as the core, this issue is increasingly being concerned by the leaders of relevant companies, prompting enterprises to tap potential innovations, reduce costs and increase efficiency, and take the path of connotative development. This article discusses how to improve the service life of slotted cutters.

First, the problem exists Slotted knife at home and abroad, its structure and shape are basically similar.

Slotting knives include upper knives and lower knives. Common knives include curved knives and curved serrated knives. Lower knives have semicircular acute knives or semicircular knives, and semicircular slot width knives. . As shown in Figure 1. The service life of the slotting knife depends on whether the quality of the slotting of the cardboard meets the product standard. Slotting quality generally decreases with the wear of the cutting edge of the tool, resulting in burrs, burrs, chipping, and scrap and other phenomena. When the product does not meet the standards, the slotting knife needs to be replaced.

Although there are certain differences in the service life of imported and domestic slotted knives, there are some problems similar to this: First, the slotting knife (upper knife) can only be used once, and the service life is short; Poor, grooving quality is not stable; Thirdly, the wear resistance of the cutting edge is poor, and some cutting edges crack locally; Fourth, frequent addition of new knives, large expenses, high production costs.

Second, the main reasons

(I) When the cutter is worn and the slitting knife is working on the cut paper, the cutting edge of the cardboard will produce a cutting movement. At the same time, the surface is subject to relative friction. In many paperboards, the amount of sand contained is 5% to l0% higher. The sand particles produce a strong grinding and scraping effect relative to the cutting edge, which gradually plastically deforms the metal on the surface of the cutting edge and causes fatigue wear off. The life of the tool decreases with the increase of the use time and the increase of the sand content (quartz sand, etc.) and impurities of the cut board.

(2) The gap between the upper and lower blades after the sharpening is irrational, and then the quality of the product is affected.

1 The form and degree of knife wear. as shown in picture 2. The upper blade face a is obviously worn within a range of about 10mm from the cutting edge, the edge of the working face b has a certain wear, the two acute angle blades become blunt, and the thickness between the two a faces becomes thinner; the lower blade working face c is from the edge In the following range of about 10mm, there is also obvious wear. The cutting edge of working face d also has certain wear. The sharp knife or right-angle knife blade becomes blunt, and the thickness between the c-face edge and the corresponding end face becomes thin.

2 Abrasion causes the gap between the upper and lower blades to change. Usually, people pay more attention to the grinding of working surfaces a and c, but less analysis and research is done on the gap changes caused by this.

3 Ignore the corresponding change in the ring width of the groove width. After the slotting knife grinding, the effect is poor. This is due to the fact that the thickness of the groove width retaining ring is fixed and the clearance between the upper and lower blade edges is unreasonable.

(C) Tool wear resistance and material and heat treatment Hardness is related to wear resistance and material hardness and hard spots in the organization of the nature, quantity, size and distribution status are related, the higher the hardness, the more refined carbides The more uniform the distribution, the better the wear resistance.

Third, to improve the life of the method This article refers to some of the objectively difficult to avoid factors or tools due to accidental injury affect the life expectancy, no longer discussed here. Our practical and practical approach through subjective efforts is to solve the problems of old knife reuse and new knife selection, thereby extending the service life of the slotted knife.

(1) Reasonable clearance and grinding of old knives to ensure reuse effect.

1. The old tool wear measured the classification grinding. In order to uniform size, standard grinding knife, reduce the amount of unnecessary edge grinding losses, grinding all the old knife on the measurement, recording, classification.

2. Inspect and classify the edge of the knife. Grinding. Where the d-plane cutting edge has cracks and other defects of the grinding d surface, until the defect polished; where the d surface has no obvious cracks and other defects, all grinding c surface. C surface wear surface flat.

(b) The preferred material is good and the hardness is high

1, to prevent abnormal edge cracks. After forging the steel can reach the shape of the required tool, but also can make the internal organization become compact, the quality of the crystal phase is improved, but it is required to avoid the forging gap during the forging process. In the heat treatment process, defects such as quenching cracks are fully considered.

2. Add new knife strictly according to the plan acceptance. Carton packaging companies generally purchase new slotting knives through outsourced purchasers. What needs attention is that they must be strictly inspected in accordance with the dimensional tolerances, materials, and hardness required by the drawings.