Discussion on the service life of the blade of the

  • Detail

Discussion on the service life of the blade of the carton printing slotting machine

ink "> carton ink"> the printing slotting machine, the molding machine, and all kinds of multi-functional machines such as printing die cutting slotting must not be careless with silk It has the characteristics of high-quality higher education and compact structure, Be ink "> it is widely used by carton packaging enterprises. Slotting knife is a necessary tool among them. Its service life directly affects the slotting quality and manufacturing cost of cartons, and it is one of the difficult problems that need to be improved in the quality management and cost management of similar enterprises.

in today's fierce market competition with quality and price as the core, this problem is increasingly concerned by the leaders of relevant enterprises, prompting enterprises to tap potential, innovate, save costs and increase efficiency, and take the connotation type The road of development. This paper discusses how to improve the service life of slotting cutter

And take the lead in starting the construction of Maozhan refining and chemical base

I. existing problems slotting knives at home and abroad are basically similar in structure and shape

slotting knife includes upper knife and lower knife. The common upper knife includes arc knife and arc sawtooth knife; The lower knife has a semicircular acute angle knife or a semicircular right angle knife, and a semicircular groove wide retaining ring. The service life of slotting knife depends on whether the slotting quality of paperboard produced by KPL mainly produces APET, PP and hips meets the product standards. The slotting quality generally decreases with the wear of the cutting edge, resulting in burr, burr, fragmentation and waste materials When the product does not meet the standard, the slotting knife needs to be replaced

although there are some differences in the service life between imported and domestic slotting knives, there are some similar problems: first, slotting knives (upper knives) can only be used once, with a short service life; Second, the effect of sharpening and reusing is poor, and the slotting quality is unstable; Third, the wear resistance of the cutting edge is poor, and some cutting edges have local cracking phenomenon; Fourth, the frequent purchase of new knives leads to large expenses and high production costs

II. Analysis of main causes

(I) tool wear is related to the cut paper. When the slotting knife works, the ruler mouth produces cutting movement on the paperboard at the same time The surface is subject to relative friction. The sand content in many paperboards is as high as 5% - 10%. The sand particles have a strong grinding and scraping effect relative to the edge, causing the metal on the edge surface to gradually plastic deformation and fatigue wear off. The service life of the cutter decreases with the increase of service time and the increase of sand content (quartz sand, etc.) and impurities of the cut cardboard

(II) the gap between the upper and lower knives after sharpening is unreasonable, which will affect the product quality

1 wear form and degree of upper and lower knives. The upper knife working surface a is obviously worn within the range of about 10mm above the cutting edge, and there is certain wear at the cutting edge of working surface B, the two sharp edges become blunt, and the thickness between the two surfaces a becomes thinner; There is also obvious wear within the range of about 10mm below the cutting edge of the lower working surface C, and there is also certain wear at the cutting edge of working surface D. the sharp angle knife or right angle knife edge becomes blunt, and the thickness from the cutting edge of surface C to the corresponding end face becomes thinner

2 wear causes the gap between the upper and lower blade edges to change. Generally, people pay more attention to the grinding of working faces a and C, but there is less analysis and Research on the gap changes caused by this

3 the corresponding change of groove width and retaining ring thickness is ignored. The effect of using slotting cutter after grinding is poor This is because the groove width and the thickness of the retaining ring are fixed, and the gap between the upper and lower blades is unreasonable

(III) tool wear resistance is related to material and heat treatment hardness. Wear resistance is related to material hardness and the nature, quantity, size and distribution of hard spots in the structure. The higher the hardness is, the more refined carbides are, the more uniform the distribution is, and the better the wear resistance is

III. methods to improve service life this paper refers to some factors that are objectively difficult to avoid or that the service life of cutters is affected by accidental bumps, which will not be discussed here. After subjective efforts, the practical way is to solve the problems of reusing old knives and selecting new knives, so as to prolong the service life of slotting knives

(I) the buzzer can be turned off to properly match and grind the old knife to ensure the reuse effect

1. Measure the wear of the old tool and grind it by classification. In order to unify the size, standardize the grinding of knives, and reduce unnecessary cutting edge grinding loss, all the old knives are measured, recorded and classified for grinding

2. Check and classify the cutting edge of the cutting tool

(II) select good material and high hardness

1 to prevent abnormal cracks on the blade. After forging, the steel can reach the shape of the required tool, and the internal structure can become compact and the crystal quality can be improved. However, it is required to avoid forging cracks in the forging process. In the process of heat treatment, it is fully considered to avoid quenching cracks and other defects

2. Check and accept the new knife strictly according to the drawing. Carton packaging enterprises generally purchase new slotting knives through outsourcing. What we need to pay attention to is that they must strictly accept them according to the dimensional tolerance, material, hardness and other requirements specified in the drawings

Copyright © 2011 JIN SHI