GB/T 29047-2021 Prefabricated directly buried insulating pipes and fittings with polyurethane foamed-plastics and high density polyethylene casing pipes

GB/T 29047-2012 Prefabricated directly buried insulating pipes and fittings with polyurethane [PUR]foamed-plastics and high density polyethylene [PE]casing pipes

GB/T 8923.1-2011 Preparation of steel substrates before application of paints and related products—Visual assessment of surface cleanliness—Part 1:Rust grades and preparation grades of uncoated steel substrates and of steel substrates after overall removal of previous coatings GB/T 18475-2001 Thermoplastics materials for pipes and fittings for pressure applications—Classification and designation—Overall Service(design) coefficient GB/T 3091-2001 Welded steel pipe for low pressure liquid delivery GB/T 3091-2008 Welded steel pipes for low pressure liquid delivery GB/T 3091-2015 Welded steel pipes for low pressure liquid delivery GB/T 8163-1999 Seamless steel tubes for liquid service GB/T 8163-2008 Seamless steel tubes for liquid service GB/T 8163-2018 Seamless steel pipes for liquid service GB/T 9711-2011 Petroleum and natural gas industries—Steel pipe for pipeline transportation systems GB/T 9711-2017 Petroleum and natural gas industries—Steel pipe for pipeline transportation systems GB/T 9711-2023 Petroleum and natural gas industries—Steel pipe for pipeline transportation systems GB/T 9711.1-1997 Petroleum and natural gas industries—Steel pipe for pipelines—Technical delivery conditions—Part 1:Pipes of requirements class A GB/T 9711.2-1999 Petroleum and natural gas industries—Steel pipe for pipelines—Technical delivery conditions—Part 2:Pipes of requirement class B GB/T 9711.3-2005 Petroleum and natural gas industries—Steel pipe for pipelines—Technical delivery conditions—Part 3:Pipes of requirements class C GB/T 12459-1990 Steel butt-welding seamless pipe fittings GB/T 12459-2005 Steel butt-welding seamless pipe fittings GB/T 12459-2017 Steel buttwelding pipe fittings—Types and parameter GB/T 13401-1992 Steel plate butt-welding pipe fittings GB/T 13401-2005 Steel plate butt-welding pipe fittings GB/T 13401-2017 Steel buttwelding pipe fittings—Technical specification GB/T 29046-2012 Test methods of technical specification for pre-insulated directly buried district heating pipes GB/T 29046-2023 Detection methods of technical specification for pre-insulated district heating pipes NB/T 47013.2-2015 Non-destructive testing of pressure equipment - Part 2: Radiographic testing NB/T 47013.3-2015 Non-destructive testing of pressure equipment - Part 3: Ultrasonic testing NB/T 47013.5-2015 Non-destructive testing of pressure equipment - Part 5: Penetrant testing NB/T 47014-2023 Pressure equipment welding process qualification SY 5257-1991 Steel Bending Pipe SY/T 5257-2012 Steel Induction Heating Bending Tubes for Oil and Gas Transportation SY/T 5257-2004 Steel bends for oil and gas transportation GB/T 3091-2025 Welded steel pipes for low pressure fluid delivery GB 50236-2011 Code for construction and acceptance of field equipment, industrial pipe welding engineering GB 50683-2011 Code for acceptance of field equipmemt,industrial pipe welding construction quality CJJ/T 254-2016 Technical specification for leakage surveillance system of directly buried heating pipe GB/T 12459-2025 Steel buttwelding piping fittings—Types and parameters GB/T 13401-2025 Steel buttwelding piping fittings—Technical specification