| 摘要 |
FIELD: process engineering. ^ SUBSTANCE: invention may be used in butt welding of railway and tram rails. Butts are machined and subjected to nitrogen hardening to depth of 0.05 to 0.1 mm. Rails butted, pressing force is applied to butt joint to heat to (Ac3+300)C(Ac3+400)C and hold it thereat for butt joint austenitisation. After upsetting, butt joint is cooled by air-water mix to "£"C("£"+400)C and, then, by air to ambient temperature. ^ EFFECT: higher hardness and strength thanks to fine-grained structure, and impact number of metal. ^ 1 tbl, 1 ex |
