Conference on Abrasion Wear Resistant Cast Iron And Forged Steel For Rolling and Pulverizing Mills – ABRASION 2024

The manufacturing process of seamless steel tubes in hot rolling mills includes piercing, pushing and stretch-reducing of the tubes. Depending on the specific steel grade, the tubes are heat-treated and hot-straightened to achieve the predefined geometric specifications of the final product. As the strength of the tube steel increases, the rolls used in the straightening machines show greater signs of wear. Hence, detailed information about the wear behavior of the rolls is of utmost importance for extending their service life and for reducing tooling costs and maintenance efforts. For this reason, the experimental study investigated the wear behavior of typical roll materials (high-chromium cast iron and cast high-speed steel) under rolling contact with selected tube steels (L80 and Q125 grades) by using a lab-scale roll test rig. The roll specimens were tested at predefined temperature (500 °C), contact load and roll slip in order to simulate the complex conditions of the real straightening process. To determine the specific wear volume over the rolling time or rolling distance, respectively, the full geometry of each specimen was captured after each of the test runs using an optical 3D scanner. Almost linear volume loss was observed beyond the initial run-in phase, which enabled determining the specific wear coefficient of the roll material for defined process conditions. Based on the specific wear coefficient the service life of the roll material was estimated as function of both the tube grade and the tube dimension. Moreover, the results of the study demonstrated that high-chromium cast iron rolls show similar performance as the more expensive high-speed steel rolls.