Factors affecting the service life of the serrated knife

Serrated knives are widely used in the paper industry, food industry, iron and steel metallurgy industry and other fields. In the process of use, due to the influence of various factors, the blade will produce varying degrees of wear, which will affect the service life of serrated knives. This article will introduce the factors affecting the service life of the serrated knife.

The following is a list of contents

1. Influence of cutting clearance on the blade

2. Effect of demineralized water on the serrated knife

3. Effect of titanium dioxide content on blade quality

4. Influence of tool machining

5. Influence of production load change on cutting tools

Influence of cutting clearance on the blade

The so-called cutting clearance is the clearance between moving and fixed knives. In a certain range, the cutting clearance is large and the cutting force required is small; On the contrary, the cutting force is large and the tool wear is also large; When the gap approaches zero, the cutting force will become quite large until the strength of the edge can not bear and fracture occurs; However, if the gap is too large, the slicing quality will be significantly affected. Therefore, the cutting clearance must be reasonably selected in production. According to experience, the cutting gap is controlled between 0.03 ~ 0.04 mm, which can not only ensure a certain cutting force but also obtain qualified slices.

Effect of demineralized water on the serrated knife

Demineralized water is indispensable in the granulation process. It not only cools the materials transported by the casting belt but also has a certain impact on the use of cutting tools. Demineralized water can timely take away the heat generated in cutting, reduce the tool wear speed, and also play a certain role in lubrication. Without demineralized water, the heat loss is slow, and the tool wear will be accelerated; however, excessive demineralized water will hinder the operation of the cutting tool and slicing, which will increase the noise and cutting consumption. At the same time, the demineralized water will also enter the mechanical transmission part. The purity of demineralized water also has a great impact on the tool. The solid impurities in demineralized water wear the tool very quickly. Therefore, the role of demineralized water in the cutting process has both advantages and disadvantages, which should be strictly controlled in actual production.

Effect of titanium dioxide content on blade quality

Titanium dioxide is a matting agent in polyester production and an indispensable additive in chemical fiber production, but titanium dioxide has an important impact on tool wear. When the content of titanium dioxide increases, the service life of the tool decreases sharply; When the content of titanium dioxide is close to zero, the service life of the tool can be very long. In normal BOPP production, the content of titanium dioxide is 10%, and the service life of ordinary carbon alloy steel tools is only 40 rain. It can be seen that titanium dioxide has a great impact on the service life of cutting tools. Without affecting the quality of polyester products, the most reasonable injection amount should be maintained as far as possible when injecting titanium dioxide.

Influence of tool machining

After normal grinding, there are many small spikes on the edge of the tool. These spikes are sharp but fragile and easy to break. After the fracture of the rear small spikes, the cutting force increases and more heat is generated, which shortens the service life of the tool. Therefore, the small spikes must be carefully treated before use to reduce local stress concentration, so as to improve the impact strength and prolong the service life of the tool. During the grinding process of the tool, the width of the blade belt of the tool shall be strictly controlled within 0.1-0.2mm; Otherwise, the cutting clearance is too large.

Influence of production load change on cutting tools

The change of production load will inevitably lead to the change of cutting conditions. Experience has proved that as the output of chips increases, the amount of titanium dioxide increases, the cutting speed, and friction heat also increase, and the service life of cutting tools will be shortened. It has been proved that the service life of the cutter under low load is much longer than that under full load. The general polyester plant does not adopt the full load production form of one for use and one for standby but uses two sets of 50% low load operation at the same time. One of the reasons is to prolong the service life of the cutting tool.