METHOD OF THE RAILS THERMAL TREATMENT Russian patent published in 2007 - IPC C21D9/04 

FIELD: ferrous metallurgy; methods of the rails thermal treatment.

SUBSTANCE: the invention is pertaining to the field of ferrous metallurgy in particular, to the methods of the thermal treatment of the railroad rails. Hardening of the railroad rail head is exercised in the water-polimeric-air medium up to 400-280°С, then - by the compressed air up to 150°С with simultaneous cooling of the rail foot by the compressed air with the temperature from the temperature of the austenization up to 150°С. The water-polimeric solutions used for production of the water-polimeric-air medium are prepared from the concentrate of the PK-M polymeric compound at the ratio of the concentrate and water in this water-polymeric solution of 1:14÷1:20. For preparation of the water-polymeric solutions it is possible to use the concentrate of Brooks Thermo A polymeric compound, in which the optimum ratio of this concentrate and the water should make 1:17÷1:25. Utilization of the invention allows to increase the set of the rails mechanical properties and the rail head hardness, to produce the high-strength wear-resistant and cold-resistant rails with the favorable (contracting) residual stresses, to increase their linearity and the service life.

EFFECT: the invention ensures production of the high-strength wear-resistant and cold-resistant rails with the increased set of the rails mechanical properties additionally including the favorable (contracting) residual stresses, the rail head hardness, the increased linearity and the service life.

2 cl, 1 tbl