SURFACE TREATMENT METHOD FOR STEEL PIPE JOINT OF EXCELLENT RESISTANCE TO GALLING

摘要

PURPOSE: To form a film of excellent resistance to stoving and resistance to wear for an oil well pipe joint by forming phosphorus manganese formed film layers on a screw section and a metal sheet section, applying a solid lubricant of a specified concentration, heat processing and forming solid lubricating film layers of a specified thickness. CONSTITUTION: Phophorus manganese formed film layers of 5μm-25μm thickness or nitrogen layers of 1μm-20μm thickness and phosphorus manganese formed film layers of 5μm-25μm thickness are formed on a screw section 3 and a metal sheet section 4 of a joint of a steel pipe. A solid lubricant containing one kind selected out of a molybdenum disulfied powder, an epoxy resin, a furan resin and a polyimide resin as an essential component and having the composition ratio of 0.5 <= (content of molybdenum disulfied)/(content of one kind selected out of an epoxy resin, a furan resin and a polyimide resin) <= 3.0 (weight ratio) is applied and heat treated to form solid lubricant film layers of 10μm-45μm thickness.