METHOD AND INSTALLATION FOR THERMAL TREATMENT OF RAILS Russian patent published in 2013 - IPC C21D9/04 C21D1/42 C21D11/00 C21D1/18 

FIELD: metallurgy.

SUBSTANCE: rail is exposed to thermal treatment, including pre-heating, additional heating, cooling. Rail is heated continuously or discretely with control according to the program-specified mode. Pre-heating is carried out to the temperature of austenitisation start (point Ac₁), not exceeding temperature of austenitisation end (point Ac₃). Additional heating is carried out by thermocycling in the field of phase α-γ transformations. In intervals between separate heating devices, soaking is carried out to balance temperatures in each cross section. The rail is first cooled down to temperature providing for fine-grained perlite structure for each cross section of a rail, then cooled under natural conditions, at the same time cooling speeds are changed at various stages of the cooling mode. The method is carried out at an installation comprising zones of pre-heating, thermocycling, homogenisation with separate heating devices and intervals arranged between them and/or devices of temperature balancing along the cross section, a cooling zone, including cooling modules with a unit of control and adjustment of cooling parameters.

EFFECT: increased level of physical and mechanical properties and increased operating resistance.

8 cl, 2 tbl, 6 dwg