Rolling mill support roll steel and heat treatment technology thereof

Abstract

The invention discloses a rolling mill support roll steel and a heat treatment technology of the rolling mill support roll steel. The steel comprises carbon, silicon, manganese, chromium, nickel, molybdenum, vanadium, sulphur, phosphorus and the balance of iron and impurity not capable of being removed. The heat treatment technology of the rolling mill support roll steel comprises the following steps of: firstly, transporting a support roll into a car bottom furnace to be wholly preheated; clamping the support roll in an induction heating machine set, and driving a workpiece to rotate; arranging an inductor in the induction heating machine set, and spirally winding the inductor by a purple copper pipe; carrying out quick differential heating on the support roll by the inductor by controlling the control inductor; exactly controlling the temperature at a set temperature in the process of heating; when a roll body reaches to the set heating depth and temperature, quickly lifting the support roll into a spraying and quenching system from the induction heating machine set; and when the temperature of the support roll is reduced at 80-150 DEG C, lifting the support roll out of the spraying and quenching system. According to the heat treatment technology, the mechanical property of the support roll can be observably improved, and the service life of the support roll can be prolonged.

Description

technical field [0001] The invention relates to a metal material and a heat treatment process, in particular to a rolling mill backup roll steel material and a heat treatment process thereof. Background technique [0002] With the development of cold rolling mills in the direction of automation, high speed, high precision, and high-quality shape control, the requirements for backup rolls are also increasing. In particular, high requirements are put forward for the hardness, uniformity, depth of hardened layer, impact resistance, peeling resistance, wear resistance and residual stress of the roll body. [0003] 9Cr2Mo, 9Cr3Mo, 70Cr3Mo, 70Cr3NiMo, 45Cr5NiMoV, 50Cr4MoV, etc. are generally selected as domestic and international materials for cold rolling backup rolls. 9Cr2Mo and 9Cr3Mo are traditional materials, and their comprehensive properties cannot meet the requirements of modern rolling mills. 45Cr5NiMoV and 50Cr4MoV have high alloying elements and high prices, which are...

AI Technical Summary

Problems solved by technology

9Cr2Mo and 9Cr3Mo are traditional materials, and their comprehensive properties cannot meet the requirements of modern rolling mills.

45Cr5NiMoV and 50Cr4MoV have high alloying elements and high prices, which are difficult for users to accept

Especially for backup roller parts after quenching treatment, surface cracks, brittle fracture, poor wear resistance and other problems often occur, so it is necessary to choose appropriate metal materials and heat treatment methods