METHOD FOR APPLYING A PROTECTIVE SURFACE LAYER TO DRILL BITS Russian patent published in 2022 - IPC B23K26/342 C23C26/02 

FIELD: mining.

SUBSTANCE: invention relates to the petroleum and gas industry, namely, to manufacture of drill bits with a strengthened surface. Method for applying a surfaced protective layer of a wear-resistant nickel-chromium alloy to drill bits includes preheating the body of the drill bit, surfacing a wear-resistant alloy on the leading and trailing sides of the blades of the drill bit, and cooling the drill bit. Preheating is conducted to a temperature of 510 to 550°C. Surfacing at the surface temperature of the body of the drill bit, equal to 495-510°C, is conducted using a wear-resistant alloy. The wear-resistant alloy is produced by adding a powder to the flame of an acetylene torch, containing, wt.%: carbon 0.6 to 0.9, silicon 2.5 to 3.5, boron 3.5 to 4.0, iron no more than 3, copper 2.1 to 2.5, molybdenum 2.4 to 2.8, chromium 30.0 to 33.0, nickel the rest. Follows is cooling to room temperature in the open air.

EFFECT: creation of a protective layer in a single surfacing operation at least without deterioration of the working characteristics of the bit.

2 cl, 1 ex, 1 dwg