Development and Factory Testing of a Technology to Make Wide Plates for 1420-mm-Diam. Tubes on a 5000 Mill

• Published in: Metallurgist (New York) Vol. 47; no. 5-6; pp. 248 - 253
• Main Authors: Efron, L. I., Il'inskii, V. I., Golovanov, A. V., Lamukhin, A. M.
• Format: Journal Article
• Language: English
• Published: New York Springer Nature B.V 01.05.2003
• ISSN: 0026-0894; 1573-8892
• DOI: 10.1023/A:1025637132001

The company Gazprom needs straight-welded pipes 1420 mm in diameter to build gas pipelines. However, such pipes are not made in Russia, and neither is skelp of the corresponding size - up to 4600 mm in width. Thus far, Russian metallurgists have succeeded in making spiral-welded pipes with a diameter of 1420 mm and a wall thickness of 15.7-18.7 mm. These pipes - which meet all of Gazprom's requirements - are made on the 2520 mill at the Volzhsk Pipe Plant from skelp with a length of 24 m. The skelp needed to make the pipes is obtained from factories in Ukraine, and their output is limited to 200,000 tons of skelp with a maximum length of 12 m. Severstal' is rebuilding plate shop No. 3 and upgrading the 5000 mill, the goal being to have modern facilities for making electric-welded pipes that will have a diameter up to 1420 mm and a wall thickness up to 40 mm and will also satisfy all present and prospective Gazprom requirements. To be able to do this within the context of its general plan of reconstruction, Severstal' is working with TsNIIchermet on several research projects. The goal of the research project being reported on in this article was to develop and factory-test on the 5000 mill a technology for the controlled rolling of wide plates to be used in the production of single-seam pipes 1420 mm in diameter. We also wanted to evaluate the properties of the resulting metal. Before the work was begun, specialists at the firm KO VNIImetmash calculated the mechanical parameters of the rolling operation with allowance for the specifications of the existing equipment of the 5000 mill. It was determined in particular that the maximum allowable load was 9000 ton-f. Two rolling schemes were examined: with a maximum load of 6500 ton-f and a maximum load of 8000 ton-f. At the lower maximum, the number of passes during the finishing stage was increased without changing the thickness of the starting plate or the finishing temperature. Calculations showed that it might be possible to subject the entire range of product thicknesses (14.5-39.6 mm) to controlled rolling on the 5000 mill.