Welded steel pipe

Classification of welded pipes: general welded pipes, straight seam welded pipes, spiral welded pipes

General welded pipe
Made of Q195A steel, Q215A carbon steel, Q235A steel. Also available in other mild steels that are easy to weld.
The steel pipe needs to be tested for water pressure, bending, flattening, etc., and has certain requirements on the surface quality. Usually the delivery length is 4-10m, and it is often required to deliver to a fixed length (or multiple feet).
The specification of the welded pipe is expressed by the nominal diameter (mm or inch). The nominal diameter is different from the actual one. The welded pipe can be divided into two types: ordinary steel pipe and thickened steel pipe according to the specified wall thickness. Welded pipes are used to transport low pressure fluids.

Straight seam welded pipe
Simple production, high production efficiency, low cost and rapid development.
Specifications: Φ21.3-457.2*1.8-14

Spiral welded pipe
The strength is generally higher than that of straight seam welded pipes, which can produce welded pipes with larger diameters from narrower billets. Spiral seam welded steel pipes are divided into automatic submerged arc welded steel pipes and high frequency welded steel pipes.

A. Spiral seam automatic submerged arc welded steel pipes are divided into two categories: Class A pipes and Class B pipes according to the pressure of the conveying medium. Type A pipes are generally welded with ordinary carbon steel Q235, Q235F and ordinary low-alloy structural steel 16Mn, and Type B pipes are welded with steels such as Q235, Q235F, Q195, etc., and are used as low-pressure fluid conveying pipes.

B.Spiral seam high frequency welded steel pipe Spiral seam high frequency welded steel pipe, there is no unified product standard, generally made of ordinary carbon steel Q235, Q235F and other steel.

Specifications: Φ219-2320*6-22

standard:
GB/T3091-1993 (galvanized welded steel pipe for low-pressure fluid transportation) is a representative material of Q235A grade steel.
The representative material of GB/T3092-1993 (galvanized welded steel pipe for low-pressure fluid transportation) is: Q235A grade steel.
GB/T14291-1992 (Welded Steel Pipe for Mine Fluid Transport) Its representative material is Q235A grade steel.
GB/T12770-1991 (Stainless Steel Welded Steel Pipe for Mechanical Structure) Its representative materials are 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb, etc.
GB/T12771-1991 (stainless steel welded steel pipe for fluid transportation) represents the material of 0Cr13, 0Cr19Ni9, 00Cr19Ni11, 00Cr17, 0Cr18Ni11Nb, 0017Cr17Ni14Mo2, etc.

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