Rolls Selection of High-Speed wire rod rolling mill

I. Preface

In the mid-20th century, due to the war and post-war reconstruction, industrial countries needed many wire rods, which led to the rapid development of wire rod rolling mills. In the mid-60s of the 20th century, the advent of high-speed torsion-free wire rod finishing mills and Stelmor-controlled cooling processes pushed the world's wire rod production technology to a new stage.

Ⅱ. Rolls Selection of High-speed Wire Rod Rolling Mill

The high-speed wire rod rolling mill has fast rolling speed, high product precision, good surface quality, a large rolling coil, and no torsion and micro tension of the entire rolling line. A high-speed wire rod rolling mill comprises a rough rolling mill, medium rolling mill, pre-finishing mill, and finishing mill.

The roughing mill is generally composed of 4~8 stands, due to the high rolling temperature, large cross-section, and deep roll groove, therefore, the rolls used for the roughing mill should have good fracture resistance, thermal crack resistance, wear resistance, and good bite performance.?

Generally, roughing roll stands adopt pearlitic ductile iron rolls with hardness HSD 45-55 or alloy semi-steel rolls with hardness HSD 45~50.

The rolls of the medium rolling mill groups are generally required to have good wear and surface roughness resistance, and there is not much difference in material selection. Therefore, the high-speed wire rod rolling mill's rolling mill generally selects pearlitic ductile iron rolls with a hardness of HSD 60 ~ 70 or alloy infinite cold hard ductile iron rolls, which are both economical and practical.

The pre-finishing mill of the high-speed wire rod rolling mill can reduce the rolling accidents of the finished wire and improve the dimensional accuracy of the finished wire rod. Therefore, the roll materials should ensure the wear resistance of the rolls.

High-speed wire rod rolling mills have a wide choice of materials for the roll rings of the pre-finishing mill group, and some manufacturers use tungsten carbide roller rings, although the wear resistance is excellent, the strength is low, and there will be fracture. The wear resistance of centrifugal composite ring and high-speed steel rolling roll is 3 times higher than that of high nickel chromium platinum infinite cold hard cast iron, and the strength is higher than that of tungsten carbide roller ring, and the price is cheaper. Therefore, centrifugal composite roll rings and high-speed steel roll will be the preferred material for the roll or roll ring of the pre-finishing mill in the future.

The high-speed wire rod finishing mill is an important factor in ensuring that the wire rod achieves high-precision rolling, so the high-speed wire rod finishing mill must use tungsten carbide roll rings, otherwise, the rolling speed and wear resistance of the roll rings will not be guaranteed. So far, the tungsten carbide roll ring of the high-speed wire rod rolling mill finishing mill has not been replaced by any material