TPT May 2014

Article

Shandong Province SiFang Technical Development Co, Ltd

GmbH & Co KG Selection and application of roll for welding steel pipe and cold roll formed steel By Yuan Hou-zhi, Liu Xing-yi, Shandong Province SiFang Technical Development Co, Ltd, China

the roll and for guiding correctly rolled piece to come in and out from the rolls. The roll consisted of the shape and material is first designed before the designing rolling mill. In a sense, the good steel product can not be produced without good roll. The good or bad roll quality influences directly the quality of rolled steel product. Because the roll is often working in adverse conditions, such as high heat, high pressure, speedily chilling and heating and attacking, the properties of the roll must be a strict requirement including strength, surface hardness, wear resistance, heat resistance, speedily chilling and heating resistance, peeling resistance, etc. Based on the different conditions, such as the kinds of produced steel product, size, property and used environment and so on, the material and property of roll should possess different requirements. For welding steel pipe roll and cold roll formed steel roll the using condition and required properties are basically the same. Through some different bending processes the strip steel is formed by rolls, therefore the high or low service life and good or bad quality of roll are directly to influence the quality and productivity of welding steel pipe and cold roll formed steel.

The steel rolling process is a main technology in steel shaped process and it is possessed of basic role for economic development of our country. Since the beginning of the twenty-first century the steel rolling technology experience of a hundred years has gained rapid development with intervening in advanced technology. In the foreseeable future, the continuous steel rolling technology using a roll as a feature will still be the main production technology in shaped process of steel rolling and its position can not be changed. Through rolled piece to directly touch with rolls the steel rolling process which is also known as “plastic deformation of metal” is achieved. The roll is the most important part in the production of steel rolling process and others included working stands, etc are all designed for mounting, supporting, adjusting and exchanging The analysis considers that the roll is an important consumption tool in the production of steel rolling, in the practical utilisation process the user must persist in the principle of first quality of rolled steel, the principle of difficultly formed degree for different steel grade and product shape and the principle of large or small sizes of rolled raw material. The selection principle and the standard of material and chemical composition selection listed in national standard for roll of welding steel pipe and cold roll formed steel are introduced, the properties of chemical composition of various rolls are analysed, and the selection principle of roll material in actual production process is summarised in this article.

1. Selecting and using of roll material 1.1. Selection principle of roll material

General principle of selection roll material is suitable for the working environment. Any materials are not universal, usually

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May 2014