Welded steel pipe refers to a steel pipe with a seam on the surface that is made by bending steel strips or steel plates into round, square and other shapes and then welding them. The blank used for welded steel pipes is steel plates or strip steel.

GB/T3091-1993 (Galvanized welded steel pipe for low-pressure fluid transportation). Mainly used for conveying water, gas, air, oil, heating hot water or steam and other generally low-pressure fluids and other pipes. Its representative material is Q235A grade steel.

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 generally low-pressure fluids and other pipes. Its representative material is: Q235A grade steel.

GB/T14291-1992 (Welded steel pipe for fluid transportation in mines). Mainly used for straight seam welded steel pipes for mine compressed air, drainage, and axial gas discharge. Its representative materials are Q235A and 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.

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

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

The model range of welded steel pipe mainly includes the following types:

DN6: nominal diameter is 6mm, outer diameter is 10mm, wall thickness is 2mm, theoretical weight is 0.39kg/m12

DN8: nominal diameter is 8mm, outer diameter is 13.5mm, wall thickness is 2.25mm, theoretical weight is 0.62kg/m12

DN10: nominal diameter is 10mm, outer diameter is 17mm, wall thickness is 2.25mm, theoretical weight is 0.82kg/m12

DN15: nominal diameter is 15mm, outer diameter is 21.25m m, wall thickness is 2.75mm, theoretical weight is 1.26kg/m‌12

‌DN20‌: nominal diameter is 20mm, outer diameter is 26.75mm, wall thickness is 2.75mm, theoretical weight is 1.63kg/m‌12

‌DN25‌: nominal diameter is 25mm, outer diameter is 33.5mm, wall thickness is 3.25mm, theoretical weight is 2.42kg/m‌12

‌DN32‌: nominal diameter is 32mm, outer diameter is 42.25mm, wall thickness is 3.25mm, theoretical weight is 3.13kg/m‌12

‌DN40‌: Nominal diameter is 40mm, outer diameter is 48mm, wall thickness is 3.5mm, theoretical weight is 3.84kg/m‌12

‌DN50‌: Nominal diameter is 50mm, outer diameter is 60mm, wall thickness is 3.5mm, theoretical weight is 4.88kg/m‌12

‌DN70‌: Nominal diameter is 70mm, outer diameter is 75.5mm, wall thickness is 3.75mm, theoretical weight is 6.64kg/m‌12

‌DN80‌: Nominal diameter is 80mm, outer diameter is 88.5mm, wall thickness is 4mm, theoretical weight is 8.34kg/m‌12

‌DN100‌: nominal diameter is 100mm, outer diameter is 114mm, wall thickness is 4mm, theoretical weight is 10.85kg/m‌12

‌DN125‌: nominal diameter is 125mm, outer diameter is 140mm, wall thickness is 4.5mm, theoretical weight is 18.24kg/m‌12

‌DN150‌: nominal diameter is 150mm, outer diameter is 165mm, wall thickness is 4.5mm, theoretical weight is 17.81kg/m‌12

These types of welded steel pipes are widely used in various industrial fields, including the transportation of water, gas, steam and other fluids.

Common materials for welded steel pipes include Q235A, Q235C, 16Mn and Q195, etc. These materials are widely used in the production of welded steel pipes, mainly for fluid transportation pipes.

Welded steel pipes have a very wide range of applications and are mainly used in the following fields:

‌Industrial and construction fields: welded steel pipes are suitable for various industrial and construction piping systems due to their high strength and corrosion resistance. It can be used as pipes for water supply, drainage, heating, etc. to meet the needs of different engineering projects.

‌Petroleum, natural gas and water conservancy fields: welded steel pipes are also widely used in fields such as petroleum, natural gas and water conservancy. It is often used to transport fluids such as oil, natural gas and water, and is one of the important pipeline transportation equipment.

‌Other fluid transportation: welded steel pipes are also used for low-pressure fluid transportation, such as water, gas, air and steam. According to the form of the weld, welded steel pipes can be divided into spiral welded pipes, straight seam welded pipes, etc., which are suitable for different fluid transportation needs.

‌Special environment applications: welded steel pipes also show good adaptability in corrosive gas or high temperature environments. For example, welded steel pipes can be used for open and concealed installations in places with corrosive gases.