How to Choose A Suitable Rolling Mill Equipment?

The rolling mill is the key equipment for rolling billets or rolling pieces. It is suitable for non-ferrous metals and ferrous metals. It is widely used in metallurgy, metal processing, building materials and other industries for hot or cold rolling of metal rollable materials. There are many types and models of rolling mills, so pay attention to choosing the right equipment when choosing.

In addition to considering the economy and the matching of slot changing cycle and downtime, it is more important to choose rolls with reasonable comprehensive performance according to different rack pass patterns, workpiece deformation characteristics, product accuracy requirements and different racks.

The main task of the roughing stand of the bar rolling mill equipment is to reduce the cross-section at high temperatures, and the rolls bear greater rolling forces at this position. The hole is deep, the downforce is large, and the roll neck strength is high. Secondly, because the rolling speed at this position is very slow, the contact time between the roll and the high-temperature billet is longer, and it should have good thermal cracking resistance, peeling resistance, impact resistance and seizure resistance. The selection of alloy steel, semi-steel, alloy ductile iron or ferritic ductile iron can meet the requirements.

Bar rolling mills generally use round pass and elliptical systems, which are mainly responsible for the extension of the rolled pieces and the provision of precise flatness of the finishing mill. The pass of the rolling mill is still deep and can withstand greater rolling forces, so the strength of the roll is very important. However, due to the excessively large roll pass size, the cooling of the groove bottom cannot be fully realized. Therefore, the roll at this position should have good thermal crack resistance, impact toughness and wear resistance.

According to the characteristics of its location, its wear resistance is higher than that of the rough rolling mill, especially the difference in hardness between the groove bottom and the groove top is basically the same. Centrifugal casting melts the molten iron on the outside of the roll and the molten iron on the inside of the roll separately. The material can be adjusted according to the requirements of the roll.

Therefore, the working layer of the roll has high density, uniform hardness, and small radial hardness difference. The casting thickness of the outer layer of the roll can be determined according to the requirements of the rolling mill. The chilled layer of the outer layer of the roll is formed by the chilling of the metal profile. The working layer is thin and the radial hardness difference is large, which cannot meet the requirements of the rolling mill. Therefore, the middle rolling mill can choose pearlite centrifugal composite rolls and alloy infinite chilled cast iron rolls, the front roll is 60-65hsd, and the rear roll is 63-68hsd.