Why seamless steel pipe called seamless steel pipe?
Seamless is relative to welded steel pipe, because welded steel pipe is welded with steel strip, seamless steel pipe is made of whole round steel empty, no welding seam.
Steel pipe is divided into seamless steel pipe and welded steel pipe two kinds: seamless steel pipe is ingot or tube billet, through the perforation made capillary, and then by hot rolling, cold rolling or cold drawn made, so seamless steel pipe is divided into hot-rolled and cold drawn two categories. Welded steel pipe is through the steel plate or steel strip after bending forming, and then welded to make, according to the form of weld is divided into longitudinal welded pipe and spiral welded pipe two kinds. It is obvious that seamless welded pipe has no weld and that welded steel pipe has weld line.
Seamless steel pipe is a hollow section, without the joint round, square, rectangular steel. Seamless steel tubes are made of ingots or billets made by piercing and are then made by hot rolling, cold rolling or cold casting. Seamless steel pipe with a hollow section, as pipe conveying fluid, compared withsteel and roundsteelinsolid, flexural torsional strength in the same time, the weight is light, is a kind of economic section steel, widely used in the manufacture of structural parts and mechanical parts, such as the oil pipe, automobile transmission shaft, bike frame and construction using steel scaffolding.