Discrimination of Shear Blade Quality

Shear blades are widely used in the use of the shearing machine. Many people believe that the higher the raw material of the CNC shearing machine blade, the better the product will be. In fact, it is not the case. The material used for the blade of the steel plate shearing machine depends on the plate to be cut. Only by choosing the right material can the cutting be smoother.

Shear blades made of T10 (carbon tool steel), Cr5Mo (chromium molybdenum alloy steel for the high-temperature environment), 9CrSi (low alloy tool steel), suitable for cutting ordinary A3, ordinary low carbon cold-rolled sheet and scrap; in addition, shearing blades made of 9CrSi (low-alloy tool steel) are also suitable for cutting harder thin steel plates.

Shear blades made of 6Crw2si (a steel grade formed by adding a certain amount of tungsten on the basis of chromium-silicon steel) and Cr12MoV (cold work die steel) is suitable for cutting hot-rolled plates, stainless steel, and medium-thick plates.

Shearing blades made of 4Cr5MoSiV1 (air quenching hardening hot work die steel), 7Cr7Mo2V2Si (high strength and toughness cold work die steel), W6Mo5Cr4V2 (high carbon and high alloy tool steel suitable for high-speed cutting), etc. The material is characterized by high-temperature resistance, not easy to anneal.

Shear blades are an essential tool for cutting metal plates, especially when cutting stainless steel products, the cutting edge of the shearing machine blade must be sharp, wear-resistant, and tough. Therefore, the quality of the shearing machine blade is the key to determining the cutting effect. We cannot distinguish the quality of the blade of the shearing machine from the surface! However, it is not difficult to distinguish through the following points.

1. Blade Price

In the case of the same material and process, the price of the shear blade is similar. Customers can first understand the market price of raw materials used in the production of shearing machine blades, and then compare the quotations of shearing machine blade manufacturers. If the quotation is lower than or slightly higher than the price of the material, then it is shoddy.

2. Production Process

In addition to the material, that is the processing technology in the production process. In the production of shear blades, every process is very important, and the most important thing is heat treatment. And we must quenched a set of qualified shear blades at least twice in the furnace to achieve a consistent blade hardness inside and outside. The cutting edge is tough but not brittle, and the effect is durable and wear-resistant. Some shear blade manufacturers, in order to reduce costs, reduce the number of quenching, or even use soil quenching. If you don’t want customers to buy such a shear blade, you should first compare the price. The second is to use a metal hardness tester on the body after purchase, and test in multiple places to see if the hardness is up to standard and consistent.

3. Cutting Accuracy

Generally, the parallelism of the blade of the shearing machine is 0.03mm, and the thickness of the full length of the blade cannot exceed 0.03mm, and if it can achieve such accuracy, we can regard it as a set of qualified shear blades. You can use measuring tools after purchase. First, compare the errors of the two ends of a single piece, then measure whether the accuracy of the entire set of blades is consistent one by one, and then check whether there is no gap at the joint, and whether it is flat and no tentacles when touched by hand.

4. Warranty

A set of high-quality and qualified shearing machine blades can be used for at least one or two years under normal use and can be re-ground for three or five years. Therefore, when purchasing, be sure to ask about the after-sales guarantee and sign an agreement. Shearing machine blade manufacturers will promise users that within a certain period of time if there are quality problems, they can be returned and exchanged unconditionally. Without such a commitment, the quality of the blade cannot be guaranteed.

Causes of Shear Blade Chipping

CNC shearing machines are used in many processing processes. In the process of use, due to the unreasonable operation of many friends, the phenomenon of blade chipping often occurs. Generally, it is often easy to cause collapse, which may be caused by some of the following aspects.

First of all, it may be that the plate to be cut is too hard. We need to pay attention to this during the operation process. We cannot use one tool to cut all materials, otherwise, it will easily lead to chipping. If we encounter very hard materials, we must change to a more suitable blade. Maintenance is very important, otherwise, the best blade will not last long in your hands.

Secondly, when cutting the plate, we also need to carefully debug the gap between the knife edges, otherwise, it will easily lead to collapse.

Once again, when cutting round steel, it is most likely to cause chipping. If it is this material, we need to be extra careful.

In the end, it may also be the quality of the blade itself. We must not choose a shear blade with poor quality because of cheapness. After all, this is a very important part of the shearing machine.

In the hydraulic shearing machine, we must know and pay attention. Specifically, there are the following:

1. In the hydraulic shearing machine, if the rectangular lower blade is used, it can be cut into four cutting edges, so that the service life of the blade in the shearing machine can be prolonged.

2. On its work surface, there is generally an auxiliary knife seat to facilitate the blade and fine-tuning adjustment, so that it has a good adjustment effect.

3. The hydraulic shearing machine, the adjustment of the blade gap, can adopt the mechanism of step-less adjustment, so as to adapt to different plate thicknesses and shearing requirements of different materials. In addition, the cutting stroke can also be adjusted appropriately. In addition, the number of cuts can be automatically counted, so that the workload can be reduced.

4. The hydraulic oil of the hydraulic shearing machine has good viscosity-temperature properties. Viscosity temperature refers to the degree to which the viscosity of the oil changes with temperature, which is usually expressed by the viscosity index. The larger the viscosity index is, the smaller the oil viscosity decreases with the temperature rise during the operation of the hydraulic system of the shearing machine, so that the internal leakage of the hydraulic system will not be too large. The working conditions of the hydraulic system of the shearing machine are generally poor. During the operation, the temperature of the hydraulic oil changes with the load and the ambient temperature, and the viscosity index is generally not lower than 90.

Hydraulic Shearing Machine

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