Views:7 Author:Site Editor Publish Time: 2018-11-05 Origin:Site
The main links of the manufacturing process of cold rolling sizing roller are melting, forging, heat treatment, processing and inspection.
Cold rolling sizing roll bears great rolling stress in the work process rolling, in addition, welding joint, inclusion, edge crack problems of rolled piece easily lead to instantaneous high temperature, making the sizing roll subjected to the strong thermal shock, causing crack, roll banding, peeling or even scrapping. Therefore, the cold rolling sizing roll should have the ability to resist cracking and spalling caused by bending stress, torsion stress and shear stress, at the same time, it should have high wear resistance, high contact fatigue strength, high fracture toughness and thermal shock strength. So how to improve the sizing roll service life has been a major issue of sizing roll manufacturing industry.
Nondestructive testing of the sizing roll is usually carried out with ultrasonic flaw detector. In the cold rolling sizing roll testing standard, generally the roll body is divided into the surface region according to the force condition, central region and middle region, and critical dimension of allowable defects of each region are prescribed respectively in accordance with the principle of fracture mechanics. The testing workers should not noly have the knowledge of roll manufacturing to determine the property of defects, but also have the sizing roll use knowledge to estimate whether these defects may cause damage in specific conditions or not.