1. Introduction of seamless steel pipe
Seamless steel pipe is a kind of circular, square, rectangular steel with hollow section and no joints around. Seamless steel pipe is made of steel ingot or solid tube blank perforated into wool tube, and then made by hot rolling, cold rolling or cold drawing. Seamless steel pipe has a hollow section, a large number of used for conveying fluid pipeline, steel pipe and round steel and other solid steel, in bending and torsional strength at the same time, light weight, is a kind of economic section of steel, widely used in the manufacture of structural parts and mechanical parts, such as oil drilling steel scaffolding.
2. History of seamless steel pipe development
Seamless steel pipe production has a history of nearly 100 years. The German Manisman brothers first invented the two-high skew piercing machine in 1885, and the invention of the periodic pipe rolling machine in 1891. In 1903, the Swiss R.C.Stiefel invented the automatic pipe rolling machine (also known as the top pipe rolling machine), and later appeared the continuous pipe rolling machine and pipe pushing machine and other extension machines, beginning to form the modern seamless steel pipe industry. In the 1930s, the variety quality of steel pipe was improved by adopting three-high pipe rolling machine, extruding machine and periodic cold pipe rolling machine. In the 1960s, due to the improvement of continuous pipe rolling machine, the emergence of three-roll perforator, especially the application of tension reducing machine and continuous casting billet success, improve the production efficiency, enhance the seamless pipe and welded pipe competition ability. In the 70′s seamless pipe and welded pipe are abreast, the world steel pipe output at a rate of more than 5% per year. Since 1953, China has attached great importance to the development of seamless steel pipe industry, and has initially formed a production system for rolling various large, medium and small pipes. Copper pipe is also commonly used ingot cross – rolling perforation, tube mill rolling, coil drawing process.
3. Use and classification of seamless steel pipe
Use:
Seamless steel pipe is a kind of economic cross-section steel, has a very important position in the national economy, widely used in petroleum, chemical industry, boiler, power station, ship, machinery manufacturing, automobile, aviation, aerospace, energy, geology, construction and military and other sectors.
Classification:
(1) According to the section shape, it is divided into circular section pipe and special-shaped section pipe
(2) According to the material: carbon steel pipe, alloy steel pipe, stainless steel pipe, composite pipe
(3) According to the connection mode: threaded connection pipe, welded pipe
(4) According to the production method: hot rolling (extrusion, top, expansion) pipe, cold rolling (drawing) pipe
(5) by use: boiler pipe, oil well pipe, pipeline pipe, structure pipe, chemical fertilizer pipe……
4, seamless steel pipe production process
① Main production process (main inspection process) of hot rolled seamless steel pipe:
Preparation and inspection of tube blank → heating of tube blank → perforation → Rolling of tube → reheating of tube in waste → fixing (reducing) diameter → heat treatment → straightening of finished pipe → finishing → inspection (non-destructive, physical and chemical, table inspection) → storage
② Cold rolled (drawing) seamless steel pipe main production process
Blank preparation → pickling lubrication → cold rolling (drawing) → heat treatment → straightening → finishing → inspection.
5. The production process flow chart of hot-rolled seamless steel pipe is as follows:
Post time: Mar-13-2023
