Heat treatment process for improving low-temperature impact work of 42CrMo bearing

Abstract

The invention belongs to the technical field of heat treatment processes, and discloses a heat treatment process for improving the low-temperature impact work of a 42CrMo bearing. The heat treatment process comprises the following quenching and tempering process parameters: the quenching heating temperature of quenching and tempering heat treatment is 840+ / -10 DEG C; the quenching soaking time (h) of the quenching and tempering heat treatment is 3.5 hours; the tempering heating temperature of the quenching and tempering heat treatment is 580+ / -10 DEG C; the tempering soaking time (h) of the quenching and tempering heat treatment is 8 hours; and a coolant adopted by the quenching and tempering heat treatment is F2000 with the concentration of 6 percent. The process solves the important technical problem that the low-temperature impact work cannot meet the requirement after a wind power bearing is treated by adopting a conventional heat treatment process; and the process greatly improves the low-temperature impact work of the wind power bearing, ensures that the wind power bearing has high reliability, and reduces hidden quality danger.

Description

technical field [0001] The invention belongs to the technical field of heat treatment technology, and in particular relates to a heat treatment technology for improving low-temperature impact energy of 42CrMo bearings. Background technique [0002] The yaw and pitch wind power bearing rings are made of 42CrMo steel as raw material. Wind power bearings are installed on wind turbines at an altitude of more than 100 meters. It is inevitable to be subjected to huge wind force for a long time, bear huge impact loads, and work at an ambient temperature of tens of degrees below zero. The special service conditions of wind power bearings determine that they must have extremely high reliability. Otherwise, once the bearings fail early, the cost of installation and disassembly alone will exceed 1 million yuan, which will bring huge economic losses to bearing users. Therefore, users The requirements for its low temperature impact energy are getting higher and higher. [0003] Low tem...

AI Technical Summary

Problems solved by technology

Since the carbides in the Trostite are in the form of fine flakes, the low-temperature impact toughness index (A KV ) is much lower than the tempered sorbite structure, a large number of strips and massive ferrite in the structure, resulting in uneven structure, and eventually lead to uneven performance, a large amount of ferrite will also lead to low local hardness

Due to the existence of ferrite and troostite, the comprehensive mechanical properties of steel are reduced, resulting in a significant reduction in the impact energy of steel. Therefore, it is difficult for wind power bearing forgings to meet the requirements of high low-temperature impact energy according to the current heat treatment process.

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