What are the national standards for welded steel pipes?

National standard for welded steel pipes:

1, GB/T309 1- 1993 (galvanized welded steel pipe for low-pressure fluid transportation)

Mainly used for conveying water, gas, air, oil, heating hot water or steam and other general low-pressure fluids. Its representative material is Q235A grade steel.

2.GB/T3092-1993 (galvanized welded steel pipe for low-pressure fluid transportation)

Mainly used for conveying water, gas, air, oil, heating hot water or steam and other general low-pressure fluids. Its representative material is Q235A grade steel.

3.GB/T14291-1992 (welded steel pipe for conveying mining fluid)

It is mainly used for straight seam welded steel pipes in mine air pressure, drainage and gas discharge in shaft. Its representative materials are Q235A and B grade steel.

4.GB/T14980-1994 (Large Diameter Welded Steel Pipe for Low Pressure Fluid Transportation)

Mainly used for conveying water, sewage, gas, air, heating steam and other low-pressure fluids. Its representative material is Q235A grade steel.

5.GB/T12770-1991(stainless steel welded steel pipe for mechanical structure)

Mainly used in machinery, automobiles, bicycles, furniture, hotel decoration and other mechanical parts and structural parts. The representative materials are 0Cr 13, 1Cr 17, 0cr19ni118Ni9, 0cr18ni.

Extended data:

A, welded pipe according to the weld shape classification:

1, straight seam welded steel pipe:

Simple production process, high production efficiency, low cost and rapid development. There are many straight welded pipes for general industry.

2, spiral welded steel pipe:

Generally, the strength is higher than that of straight welded pipe. Welded pipes with larger diameters can be produced from narrow blanks, and welded pipes with different diameters can also be produced from blanks with the same width. However, compared with the straight seam pipe with the same length, the length of the spiral welded steel pipe increases by 30~ 100%, and the production speed is low. Therefore, straight seam welding is mostly used for welded pipes with smaller diameter, and spiral welding is mostly used for welded pipes with larger diameter.

Second, the welded pipe according to the purpose of classification:

1, common welded steel pipe:

Usually, welded steel pipes are used to transport low-pressure fluids. Made of Q 195A, Q2 15A, Q235A steel or other low-carbon steel that is easy to weld. Steel pipes have to undergo water pressure, bending, flattening and other experiments, which have certain requirements for surface quality. Usually the delivery length is 4- 10m, and it is often required to deliver according to the length (or double the length).

The specifications of welded pipes are expressed in nominal caliber (millimeters or inches). The nominal caliber is different from the actual situation. Welded pipes can be divided into ordinary steel pipes and thickened steel pipes according to the specified wall thickness, and steel pipes can be divided into threaded and non-threaded pipes according to the pipe end form.

2, galvanized welded steel pipe:

In order to improve the corrosion resistance of steel pipes, common steel pipes (black steel pipes) were galvanized. Galvanized steel pipes are divided into hot dip galvanizing and electrical steel zinc. Hot-dip galvanizing has a thick zinc layer and low cost.

3, oxygen blowing welding steel pipe:

Generally, small-diameter welded steel pipes are used as oxygen blowing pipes for steelmaking, and there are 8 kinds of steel belts with specifications of 08, 10, 15, 20 or Q 195-Q235. In order to prevent corrosion, some of them are aluminized.

4, wire sleeve:

It is also a common carbon steel welded steel pipe, which is used in concrete and various structural power distribution projects. Commonly used nominal diameters range from13-76mm. ..

5, metric welded steel pipe:

The welded steel pipe, which is in the form of seamless pipe and expressed by outside diameter * wall thickness mm, is made of ordinary carbon steel, high-quality carbon steel or ordinary low-alloy steel by hot and cold strip welding or cold drawing after hot strip welding.

Metric welded pipes can be divided into general-purpose and thin-walled pipes, which are often used as structural parts, such as transmission shafts or conveying fluids, and thin-walled pipes are used to produce furniture and lamps. Ensure the strength and bending test of steel pipe.

References:

Baidu Baike welding steel tube