THERMAL TREATMENT METHOD OF WEAR RESISTANT BUSHINGS OF OIL AND GAS EQUIPMENT DRILLING PUMP FROM TOOL CHROMIUM STEELS Russian patent published in 2019 - IPC C21D9/08 C21D1/42 C21D1/18 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to production of parts of drilling oil and gas equipment, in particular, cylindrical bushings of drilling pump from steel H12MFL, operating under conditions of abrasive wear, corrosion action and high variable pressure. To achieve technical result, steel is melted in induction furnace, centrifugal casting and heat treatment. Heat treatment includes heating of inner surface of bushing at installation of high-frequency currents to temperatures of 1,050–1,075 °C, holding for 8–10 minutes, cooling with compressed air for 10–20 minutes to temperature not lower than 200 °C, final cooling in tank with water for 3–5 minutes and tempering at 200 °C for 180–220 minutes, wherein after final cooling, cold treatment is carried out at -70 °C for 20 minutes.

EFFECT: increased service life of cylinder bushings in 1,5-1,8 times (up to 1,000 hours) and manufacturing cost reduction in 1,5 times.

1 cl, 5 dwg