Welded steel pipe is shaped up by crimping steel plate or steel belt and then it was made after welding. Welded steel pipe can be classified into longitudinally-welded pipe and spiral welded steel pipe according to the ways of welding. The common forming technique of longitudinally-welded pipe is UOE forming process and JCOE steel pipe forming process. According to the application, welded steel pipe is classified into general welded pipe, galvanized welded pipe, oxygen blast welded pipe, electric wire conduit, metric welded pipe, roller tube, deep well pump pipe, automobile tube, transformer tube, electric welding thin walled pipe, electric soldering special pipe and spiral welded pipe.
General
welded steel pipe fabricated by Steel Q195A, Q215A, and Q235A is used for conveying low-pressure fluid. It also can be manufactured by other mild rolled steel for easier welding. Steel pipe should be conducted some experiments such as hydraulic pressure, bending, battering and so on and so forth. Production manufacturers can do a more advanced detection for steel pipe in terms of their own conditions. Welded steel pipe usually has certain requirements for surface quality. The delivery length is usually four to ten meters. Moreover, manufacturers can deliver the goods by sizing or ruler-multiplying according to actual production requirements. The specification of welded pipe in nominal diameter express nominal diameter is different from the actual nominal diameter. According to the regulations of the length of wall thickness, welded pipe has two kinds: thin-wall steel tube and thick-wall steel tube.
Steel pipe also has two kinds: thread steel pipe and steel pipe without thread according to pipe ends.
For the price of welded steel pipe is lower than that of south seamless pipe which has the same specifications, welded steel pipe is widely used in low-pressure fluid transmission engineering, steel structure engineering, etc.