A production method of high temperature resistant cutting edge of medium and heavy plate shearing machine

Abstract

The invention relates to a high-temperature-resistant shear blade of a medium-thick plate shearing machine, and a production method of the shear blade. The shear blade comprises a blade body, wherein the blade body comprises the components of Fe, Cr and Ni, and the composition percentages of Cr alloy content and Ni alloy content are 5.2-5.8% and 1.65-1.95% respectively. The production method of the shear blade comprises the following steps that (1) a casting with the composition percentages of the Cr alloy content and the Ni alloy content of 5.2-5.8% and 1.65-1.95% respectively is produced; (2) the casting is forged; (3) a forging is preheated at 940 DEG C; (4) the forging is heated at 1016 DEG C (in a furnace control atmosphere); heat preservation is performed for 15min; air cooling is performed; and (5) the forging is tempered twice at 550 DEG C, and tempered for 2h each time. According to the shear blade and the production method, the high-temperature hardness of the shear blade is improved obviously; a hardness value reaches HRC (Rockwell Hardness) 50-55 at a high temperature (500-700 DEG C); change of the components reduces a critical cooling rate of steel, so that the hardenability of the steel is improved; a through hardening layer can reach 6mm; the wear-resisting property is improved; the shearing quantity of a single blade surface is greater than or equal to 40,000t; the service cycle is prolonged; and the shearing efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of shearing machines, and in particular relates to a production method of a high-temperature-resistant cutting blade of a medium-thick plate shearing machine. Background technique [0002] In the medium and heavy plate production line, most steel plates need to be finished by shearing machines to cut both sides, segmented to length, etc. before they can be sold as finished products. At present, most of the cutting blades of medium plate shears in use in China are made of H13 material, namely: 4Cr5MoSiV1. The heat treatment process is: preheating at 790°C, heating at 1010°C (furnace control atmosphere), heat preservation for 5 to 10 minutes, air cooling, and tempering at 550°C. The hardened layer is generally 3mm, and the hardness of the hardened layer is HRC50-55, but its high-temperature (≥500°C) hardness is lower, about HRC43-48, and the high-temperature (≥500°C) wear resistance is poor, and the single-edg...

AI Technical Summary

Problems solved by technology

At present, most of the cutting blades of medium plate shears in use in China are made of H13 material, namely: 4Cr5MoSiV1. The heat treatment process is: preheating at 790°C, heating at 1010°C (furnace control atmosphere), heat preservation for 5 to 10 minutes, air cooling, and tempering at 550°C. The hardened layer is generally 3mm, and the hardness of the hardened layer is HRC50-55, but its high-temperature (≥500°C) hardness is lower, about HRC43-48, and the high-temperature (≥500°C) wear resistance is poor, and the single-edge shear Quantity ≤ 30,000 tons, if it exceeds this value, the cutting edge will have rounded corners, the sheared product will be torn, the shearing surface is irregular and other defects, resulting in unqualified products

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