The main links in the manufacturing process of cold-rolled work rolls and cold-rolled intermediate rolls are smelting, forging, heat treatment, processing and inspection.
Cold-rolled work rolls and cold-rolled intermediate rolls have to bear a lot of rolling stress during the working process. In addition, problems such as welds, inclusions, and edge cracks in the rolled piece can easily lead to instantaneous high temperatures, which make the work rolls subject to strong thermal shocks. Cause cracks, sticking, peeling and even scrapping.
Therefore, cold-rolled work rolls and cold-rolled intermediate rolls must have the ability to resist cracking and spalling caused by bending stress, torsional stress, and shear stress, and also have high wear resistance, high contact fatigue strength, and high Fracture toughness and thermal shock strength, etc.
Therefore, how to improve the service life of the roll has always been a major problem faced by the roll manufacturing industry.
Non-destructive testing of rolls is usually carried out with ultrasonic flaw detectors. In the flaw detection standards of cold-rolled work rolls and cold-rolled intermediate rolls, the roll body is usually divided into a surface area, a central area and an intermediate area according to the stress, and then the critical size of the allowable defects in each area is specified according to the principle of fracture mechanics. Flaw detectors should have knowledge of roll manufacturing in order to determine the nature of defects, and should also have knowledge of roll use in order to estimate whether these defects may cause service damage under specific conditions of use.
Leading Manufacturer of High-Performance Work Rolls - LMM GROUP
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