Welded steel pipe, also known as welded pipe
, is a steel pipe welded with steel plate or strip steel after crimping. Generally, the length is 6m. Welded steel pipe has the advantages of simple production process, high production efficiency, many varieties and specifications and less equipment investment, but its general strength is lower than that of seamless steel pipe.
With the rapid development of high-quality strip continuous rolling production(welded pipe)
and the progress of welding and inspection technology, the weld quality is continuously improved, the varieties and specifications of welded steel pipes are increasing, and seamless steel pipes are replaced in more and more fields. Welded steel pipes are divided into straight welded pipe and spiral welded pipe according to the form of weld. Classification by production method: process classification - arc welded pipe, resistance welded pipe, (high frequency, low frequency) gas welded pipe, furnace welded pipe.
Straight seam welding
is adopted for small diameter welded pipe, while spiral welding is mostly adopted for large diameter welded pipe; According to the end shape of steel pipe, it is divided into circular welded pipe and special-shaped (square, rectangular, etc.) welded pipe; According to different materials and uses, it is divided into welded steel pipe for mining fluid transportation, galvanized welded steel pipe for low-pressure fluid transportation, electric welded steel pipe for belt conveyor idler, etc. According to the specification and size table in the current national standard, it is sorted from small to large according to outer diameter * wall thickness.