Heat treating method for driving roll and driving gear of rolling mill

Abstract

The invention relates to a heat treating method for a driving roll and a driving gear of a rolling mill. The heat treating method comprises the following steps: I insulating the driving roll in a salt bath furnace at the temperature of 980 DEG C-1080 DEG C for 40-50 minutes, then suspending into quenching oil with the temperature of 20 DEG C-80 DEG C for cooling, cooling the roll to the temperature below 120 DEG C, II putting the driving roll into a nitrate furnace with the temperature of 510 DEG C-600 DEG C for tempering three times, wherein each time lasts 3.5-5 hours, air cooling after the first two times tempering, performing the third tempering after cooling the temperature of roll lower than 60 DEG C; cooling to the room temperature after performing the third tempering; III carrying out a partial high-temperature tempering to the driving gear of the tempered roll, immersing the whole driving gear into the nitrate furnace with the temperature of 560 DEG C-680 DEG C for 1-4 hours and then oil cooling, cooling the roll to the temperature below 40 DEG C. According to the invention, the driving gear processed by the heat treatment method has high impact resistance.

Description

Technical field [0001] The invention relates to a heat treatment method for driving rollers and driving teeth of a rolling mill. Background technique [0002] The driving roller of the rolling mill is connected with the power motor through its own driving teeth, and is responsible for the driving task of the entire roller system. [0003] The existing heat treatment method for driving rollers and driving teeth of a rolling mill is a deep hardenable driving roller with integral heat treatment. After heat treatment, the hardness of the driving teeth is the same as the hardness of the roll body (58-60HRC), and the strength of the driving teeth is high and the impact resistance is insufficient. . During the rolling process, the rolling mill needs to stop urgently when it encounters steel strip fracture or other failures. The instant inertia generated by the entire set of rolls and the impact force of the broken steel strip on the rolls are all concentrated on the drive teeth of the dr...

AI Technical Summary

Problems solved by technology

[0003] The existing heat treatment method for the driving roll and driving teeth of the rolling mill is a deep hardenable driving roll with overall heat treatment. After heat treatment, the hardness of the driving teeth is the same as that of the roll body (58-60HRC), and the strength of the driving teeth is relatively high and the impact resistance is insufficient.

During the rolling process of the rolling mill, if the steel strip breaks or other faults need to be stopped urgently, the momentary inertia of the whole set of rolls and the impact force of the broken steel strip on the rolls are all concentrated on the drive teeth of the drive roll, resulting in Extremely high torque can easily lead to broken teeth of the drive roller and scrap it

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