METHOD FOR HEAT TREATMENT OF RAILWAY WHEELS Russian patent published in 2022 - IPC C21D9/34 

FIELD: railway transport.

SUBSTANCE: invention relates to heat treatment of railway wheels. The method for heat treatment of railway wheels made of steel containing, wt.%: C 0.55 to 0.63, Mn 0.50 to 0.90, Si 0.22 to 0.45, Cr ≤ 0.20, Ni ≤0.25, V 0.02 to 0.07, Mo 0.04 to 0.06, Fe the rest, includes heating the wheel to the austenisation temperature, cooling the working layer of the wheel rim elements, followed by holding the wheel in the air and tempering. The working layer of each wheel rim element is therein cooled for 300 seconds simultaneously, wherein the flow rate of water or air for each wheel rim element during periods of cooling, respectively, is controlled while cooling: along the tape line of the wheel for the first period of 15 seconds with a water flow rate of up to 0.012 l/cm²·s, for a period of 15 seconds with a water flow rate from 0.012 to 0.016 l/cm²·s, for a period of 270 seconds with a water flow rate from 0.016 to 0.049 l/cm²·s and along the outer side surface of the wheel rim for the first period of 15 seconds with a water flow rate up to 0.035 l/cm²·s,for a period of 15 seconds with a water flow rate from 0.035 to 0.038 l/cm²·s, for a period of 270 seconds from 0.038 to 0.044 l/cm²·s, and the inner side surface of the wheel rim is cooled for the first period of 180 seconds without water flow and with an air flow rate of 0.015 m³/cm²·s, for a period of 60 seconds with a water flow rate of 0.003 l/cm²·s and air flow rate of 0.015 m³/cm²·s, for a period of 60 seconds with a water flow rate from 0.003 to 0.005 l/cm²·s and air flow rate of 0.015 m³/cm²·s.

EFFECT: increase in the wear resistance of the working layer of the rim due to the obtained homogeneous structure of thin-plate perlite both directly on the surface and at the depth of the rim, obtained consistently high mechanical properties of the wheel rim and the rim area of the wheel disk.

1 cl, 5 tbl, 1 ex