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Existing traditional restoration techniques is surfacing welding technology, this technology combined with sexual difference, service life is very short, all the drilling companies are not willing to repair again, causing enormous waste of petroleum enterprise. And restore refers to the special structure of plasma spray gun zhongtong into the working gas and dc power supply, high frequency spark producing the excitation of arc, plasma arc electromagnetic contraction after spray gun, cooling and nozzle mechanical contraction after three effect formed a bundle of energy concentrated high speed jet plasma arc, on the surface of oil drill pipe and drill pipe and drill ontology to repair material powder, form a circle in drill pipe and drill bit dense non-porous, bright and neat, high hardness, and combined with joint high wear-resistant alloy with high strength. Plasma repair technology combined with strong sex, after repair with new drill pipe and drill organizations, performance, and the cost is much lower than the cost of the new drill pipe and drill bit.