Seamless steel pipe is a kind of circular, square and rectangular steel with hollow section and no joints around. Seamless steel pipe is made of steel ingot or solid pipe blank by piercing and then by hot rolling, cold rolling or cold drawing. Seamless steel pipe has a hollow section, which is widely used as a pipeline for conveying fluid. Compared with solid steel such as round steel, the steel pipe has a lighter weight when the bending and torsional strength are the same. It is a kind of economic section steel, widely used in manufacturing structural parts and mechanical parts, such as steel scaffold of petroleum drill, etc.
Seamless steel pipe is a kind of economic section steel, which plays an important role in the national economy. It is widely used in petroleum, chemical industry, boiler, power station, ship, machinery manufacturing, automobile, aviation, aerospace, energy, geology, construction and military industry.
Production process of seamless steel pipe
① main production process (main inspection process) of hot-rolled seamless steel pipe:
Preparation and inspection of tube blank → heating of tube blank → piercing → rolling tube → reheating of raw tube → sizing (reducing) diameter → heat treatment → straightening of finished tube → finishing → inspection (non-destructive, physical and chemical, bench inspection) → warehousing
② main production process of cold rolled (drawn) seamless steel pipe
Billet preparation → pickling and lubrication → cold rolling (drawing) → heat treatment → straightening → finishing → inspection
The production process flow chart of hot-rolled seamless steel pipe is as follows: