Boronizing treatment of steel screw barrel surface
Published:
2022-10-13 11:50
Screw and barrel are mostly scrapped due to large gap caused by wear, which can not be extruded and injected normally. Few of them fail due to insufficient strength. Especially, in addition to strength, more consideration should be given to structural commonweal and thermal inertia in the design of barrel, and the wall thickness determined by the latter two factors should be far greater than the calculated value of strength conditions
Screw and barrel are mostly scrapped due to large gap caused by wear, which can not be extruded and injected normally. Few of them fail due to insufficient strength. Especially, in addition to strength, more consideration should be given to structural commonweal and thermal inertia in the design of barrel, and the wall thickness determined by the latter two factors should be far greater than the calculated value of strength conditions
The chrome plated screw and barrel of 45 # steel and 40Cr steel commonly used in China have uneven coating and low fastness to collective bonding, which will cause local peeling during work and rapid wear or corrosion. Compared with the performance of nitriding screw and barrel only, they are better and are widely used at present. Their disadvantages are that nitriding steel has high price, nitriding layer has low hydrogen chloride corrosion resistance, and surface hardness and wear resistance are still difficult to meet the requirements of extrusion The need for injection and processing of reinforced plastics. Improving the surface hardness and wear resistance of the extruder screw, the injection molding machine screw and the barrel has become a key technical issue in the plastic processing industry to improve productivity, improve plasticizing quality and reduce production costs. This paper only conducts and tests the feasibility of the boronizing treatment process for the surface of 45 steel screw and barrel, and verifies it in the form of product installation assessment
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