Implementing Single‐Roller Hard Reduction Technology for High‐Speed Production of High‐Carbon Hard Wire Steel Billets

Abstract

The production of high‐carbon hard wire steel at high speeds necessitates the use of appropriate technical support to ensure cost‐efficiency and optimal performance of the special steel casting machine. This study investigates the industrial application of single‐roller hard reduction technology in a domestic steel plant for the production of high‐carbon hard wire steel billets, specifically of section 165 × 165 mm. The produced billets meet all customer specifications and demonstrate the benefits of this approach, including lower comprehensive costs, suitability for modification, and advanced technical concepts. These features make this method compatible with a wide range of billet casting machines, from standard to specialized. In this research, discussion is done on the reduction process, the layout of withdrawal and straightening units (WSUs), and the optimal casting speed. It is concluded that bow‐type billet casting machines using rigid dummy bars can achieve single‐roller hard reduction by only three WSUs, offering lower comprehensive costs and suitability for modification. This approach is particularly beneficial for small billet casting machines undergoing an upgrade from general to high‐quality and ultimately to special steel. During the process of increasing the central density of the billet and improving central defects using single‐roller hard reduction technology, it is observed that defects in the central region gravitated toward the center. For billet casting machines with a bow radius of 10 m, considering process tolerance, the maximum casting speeds achievable with single‐roller hard reduction are 2.95–3.40 m min−1 for a section of 150 × 150 mm, 2.60–3.0 m min−1 for a section of 160 × 160 mm, and 2.45–2.80 m min−1 for a section of 165 × 165 mm. To achieve higher casting speeds for high‐carbon hard wire steel, it is necessary to modify the machine configuration to flexible dummy bars.