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Classification And Various Uses Of Welded Steel Pipes

Feb. 11, 2020

Welded pipes are also called welded steel pipes, which are basically made of steel plates or strips that have been welded after being crimped. The production process of welded steel pipe is simple, the production efficiency is high, there are many varieties and specifications, and the equipment cost is small, but the general strength is lower than that of seamless steel pipe. Since the 1930s, with the rapid development of high-quality strip steel rolling production and the improvement of welding and inspection technology, the quality of welds has been continuously improved, and the variety and specifications of welded steel pipes have been increasing, and they have replaced Seam steel pipe. Welded steel pipe is divided into straight seam welded pipe and spiral welded pipe according to the form of weld.

Seamless Elbow

Seamless Elbow

First, the classification of welded pipe

Welded pipes are classified according to purpose: they are divided into general welded pipes, galvanized welded pipes, oxygen blown welded pipes, wire sleeves, metric welded pipes, idler pipes, deep well pump pipes, automotive pipes, transformer pipes, electric welding thin-walled pipes, electric welding Shaped pipe and spiral welded pipe.

Application range of welded pipe

Welded pipe products are widely used in boilers, automobiles, ships, light-weight door and window steel, furniture, various agricultural machinery, scaffolding, wire threading pipes, high-rise shelves, and containers. Can meet customer requirements, special specifications of welded pipe can be processed according to user requirements.

Third, the theoretical calculation method of welded pipe weight

The theoretical calculation method of welded pipe weight has formulas to follow;

The theoretical weight of steel pipe per meter (the density of steel is 7.85kg / dm3): W = 0.02466 (D-S) S

Where: W--theoretical weight per meter of steel pipe, kg / m;

D--Nominal outer diameter of steel pipe, mm;

S--Nominal wall thickness of steel pipe, mm.

4.Official definition and industrial use of welded pipe

The custom stainless steel pipe supplier believes that the blanks used for welding steel pipes are steel plates or strip steels, which are divided into furnace welded pipes, electric welded (resistance welded) pipes and automatic arc welded pipes due to their different welding processes. There are two types of welded pipe: straight seam welded pipe and spiral welded pipe. Because of its end shape, it is divided into round welded pipes and special-shaped (square, flat, etc.) welded pipes. Welded pipes are divided into the following varieties due to their different materials and uses:

1. GB / T3091-1993 (galvanized welded steel pipe for low-pressure fluid transportation). It is mainly used to transport water, gas, air, oil, and generally lower pressure fluids such as heating hot water or steam and other purposes. Its representative material is Q235A grade steel.

3, GB / T14291-1992 (mining fluid conveying welded steel pipe). It is mainly used for straight seam welded steel pipes for mine pressure, drainage and shaft gas discharge. It represents the material Q235A, B grade steel. GB / T14980-1994 (Large diameter electric welded steel pipe for low pressure fluid transportation). Mainly used for conveying low-pressure fluids such as water, sewage, gas, air, heating steam and other purposes. Its representative material is Q235A grade steel.

4. GB / T12770-1991 (stainless steel welded steel pipe for mechanical structure). Mainly used in machinery, automobiles, bicycles, furniture, hotel and restaurant decoration and other mechanical parts and structural parts. Its representative materials are 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb and so on.

5. GB / T12771-1991 (stainless steel welded steel pipe for fluid transportation). Mainly used to transport low-pressure corrosive media. Representative materials are 0Cr13, 0Cr19Ni9, 00Cr19Ni11, 00Cr17, 0Cr18Ni11Nb, 0017Cr17Ni14Mo2 and so on.