PROCESS OF DEPOSITION OF PROTECTIVE COATS ON METAL PIPES AND PLANTS FOR ITS REALIZATION Russian patent published in 2000 - IPC

FIELD: coating of metal pipes used in metallurgy, mechanical engineering, construction industry, petroleum refining industry and public utilities. SUBSTANCE: process includes cleaning of outer surface of pipe first with electric arc discharges under atmospheric pressure in atmosphere of protective, reducing or protective-reducing gas, then with mechanical means and again with electric arc discharges under mode of rising section of volt-ampere characteristic with use of graphite as anode, deposition of protective coat on outer surface of pipe in vacuum or at exit from vacuum and subsequent cooling with liquid cooling agent. Plant for realization of process has vacuum chamber with sluice system, vacuum treatment system and mechanical cleaning unit, unit of electric arc cleaning under atmospheric pressure with electric arc modules and gas supply system, aggregate for deposition of protective coats and system cooling with liquid cooling agent. EFFECT: increased productivity, improved quality of coats and prevention of pollution of environment. 2 cl, 2 dwg