Seamless steel tubes are no seams around a hollow section, round, square, rectangular steel. Seamless steel tube is made from perforated or solid billet of steel ingot capillary, then made of hot-rolled, cold-rolled or cold drawn. Seamless hollow sections, a large number of for transmission fluid pipe, steel and solid steel round bar compared to resistance to bending and torsional strength is the same, weighs less, is a kind of economic section steel, widely used in the manufacture of structural components and mechanical parts such as drill, propeller shafts, bicycle frames and steel scaffolding used in the construction.
Seamless steel tube production: hot, thermal expansion, cold drawing, cold rolled, centrifugal casting steel seamless steel tubes. Seamless steel tube size: 8-1240x1-200 mm.
Welded steel pipes are used in a strip or plate bending deformation of circle, square shape, then welded, surface of joints of steel tubes. Welded blanks are steel plates or strips. According to the welding method can be divided into electric arc welding, high frequency or low frequency electric resistance welding pipe, gas pipe, stove pipe, Bondi, pipes and so on. Welded steel pipe: used in oil drilling and machinery manufacturing. Stove pipe: use as a water-gas tubes, large-calibred straight seam welded pipe for high pressure oil and gas transmission, such as spiral welded pipe used in oil and gas transportation, pipe piles, piers, etc. Classified according to the weld shape straight seam welded pipe and spiral welded pipe straight seam welded pipe: the production process is simple, high efficiency, low cost, rapid development. Spiral welded pipe: high strength than welded, can narrow the billet production of large diameter welded pipes, you can use the same width of the billet production of different diameter of the pipe. But compared with the straight seam pipe of the same length, weld length 30~100%, and lower production rate. Therefore, most small-diameter pipe used straight seam welding, large-diameter pipe is mostly used spiral welding. According to purpose can be divided into general pipe, galvanized pipe, blowing pipe, wire and tube, metric pipe, roller tubes, pump tube, tube, transformer for car tubes, welding of thin-walled tube, welded rectangular pipe and spiral welded pipe.