Mastering the production of rail chairs of type KB 65

• Published in: Metallurgist (New York) Vol. 44; no. 2; p. 102
• Main Authors: Shleining, L I, Shargunov, A V, Melnichenko, A V
• Format: Journal Article
• Language: English
• Published: New York Springer Nature B.V 01-02-2000
• ISSN: 0026-0894; 1573-8892
• DOI: 10.1007/BF02463541

In 1999, NOSTA developed and introduced a technology to roll billets that could be used to make KB 65 rail chairs (flanged rail tracks?), thereby expanding the product mix. These rail chairs are mainly used in laying track on factory grounds. The billets were made of steels 3sp and 4sp to meet the GOST 16277 specification. Representatives from the Moscow Railroad and Ministry of Railroads (MPS) recommended that steps be taken to decrease the height reduction of the forged flanges so that they could also be used on rail lines belonging to the MPS. Increasing the carbon equivalent of the steel lowered the height reduction from 3.5 mm (carbon equivalent of 0.295%) to a height reduction of 2.06 mm for a carbon equivalent of 0.443%. Statistical analyses (linear regression) confirmed that these chairs can be used on MPS tracks and factory grounds. "Hard" heats (higher carbon equivalent) require additional high-temperature tempering at 650-700 deg C to improve ductility. Increasing the Mn content to 1.1% allows attainment of a single treatment for normalization, substantially reducing production cost of ferromanganese additions and multiple heat treatments.