GB steel pipes

The GB steel pipes are made from a ingot or a solid billet through piercing, and then by hot rolling, cold rolling or cold dial.

The GB seamless steel pipe is made of steel ingot or solid tube blank through perforation, and then made by hot rolling, cold rolling or cold drawing. GB steel pipe has an important position in China's steel pipe industry.

Tubing shall be made seamless, plain or upset and coupling with high-seal connections. Coupling-free connections are possible.


According to incomplete statistics, there are more than 240 national standard steel pipe production enterprises and more than 250 seamless steel pipe units.

GB/T 12770-2002  

Stainless steel welded pipe for mechanical structure

GB/T 12771-2000

Welded stainless steel tubes for fluid transport

GB/T 13793-1992  

Straight seam welded steel pipe

GB/T 14975-2002
Seamless stainless steel structure
GB/T 14976-2002

Stainless steel seamless tubes for fluid transport

GB/T 18984-2003

Seamless steel tubes for low temperature pipe

GB/T 3639-2000

Cold drawn or cold-rolled precision seamless steel tube

GB 3087-1999

Seamless steel tubes for low and medium pressure boiler

GB/T 3091-2001

Welded steel pipe for low pressure liquid delivery

GB 5310-1995

Seamless steel tube for high pressure boiler

GB/T 5312-1999

Marine carbon and carbon manganese steel seamless steel pipe

GB 6479-2000

Seamless steel tubes for high-pressure chemical fertilizer equipment

GB/T 8162-1999

Seamless steel tubes for structure

GB/T 8163-2008

Seamless pipe conveying fluid

GB 9948-2006

Seamless steel tubes for petroleum cracking

GB/T 14976-2002

Stainless steel seamless tubes for fluid transport

GB/T 20409-2006

For high pressure boiler seamless pipe thread

GB/T 14291-2006

Welded steel pipe for mine fluid transport

GB 9948-2006

Seamless steel tubes for petroleum cracking

CJ/T 3022-1993

Spiral seam submerged arc welded steel pipe for urban heating

GB/T 9711.1-1997

Industrial oil gas transportation pipe technical delivery conditions - part first: steel pipes

SY/T 5038-1992

Spiral seam high frequency welded steel pipe for ordinary fluid transmission pipeline


Seamless steel tubes for boilers and heat exchangers


Welded steel tubes for boilers and heat exchangers

SY/T 5037-2000

Spiral seam submerged arc welded steel pipe for low pressure fluid transmission pipeline

DL/T 5017-2007

Specification for fabrication, installation and acceptance of penstocks for hydropower and water conservancy projects

GB steel pipe size and tolerance

National standard steel pipe weight formula: [(outer diameter - wall thickness) * wall thickness] * 0.02466 = kg / m (weight per meter)

Deviation level Standardized outer diameter tolerance
D1 ±1.5%,min ±0.75 mm
D2 ±1.0%。min ±0.50 mm
D3 ±0.75%.min±0.30 mm
D4 ±0.50%。min ±0.10 mm



DIN/EN steel pipe
GB steel pipes
JIS seamless pipes

Tech & Service of Seamless pipe

Seamless pipes are extensively applied for the nuclear device, gas, petrochemical, ship building and boiler industries. Seamless pipes dominates 65% of market share in Chinese boiler industry.

How to make seamless pipe(seamless pipe process)?
Hot Piercing Workshop
Piercing process
The cross roll piercing and pilger rolling process in the size range from approx. 250 to 660 mm outside diameter.
Precision cold drawn steel tube production process
Pipe weld cracks
often follow different mechanisms can be divided into two types of thermal cracking and cold cracking.
How to calculate a steel pipe and tube theoretic weight
Calculate a steel pipe?
Pipe fittings are necessary to join together pipes, or to change the direction of an existing pipe.
Pipe beveling
Pipe beveling is the process where an angle is formed between the edge of the end of a pipe or tube and a plane perpendicular to the surface.
Steel pipe cutting machine
Pipe cutting
Cutting tools have a grinding wheel piece cutting machine (also known as toothless saw), hand saw, cutter and other hand tools.
Packing the steel pipes
There are probably hundreds of different methods for packing a pipe, and most of them have merit, but there are two principles that are vital for any method.


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