GB/T 35842-2026 Technical requirements for pre-insulated directly buriedvalve of urban heating

GB/T 35842-2018 Technical requirements for pre-insulated directly buried valve of urban heating

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 3091-2025 Welded steel pipes for low pressure fluid 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 14976-2002 Stainless steel seamless tubes for fluid transport GB/T 14976-2012 Seamless stainless steel pipes for fluid transport GB/T 14976-2025 Seamless stainless steel pipes for fluid transport GB/T 20674.1-2006 Plastics pipes and fittings—Equipment for fusion jointing polyethylene systems—Part 1:Butt fusion GB/T 20674.1-2020 Plastics pipes and fittings—Equipment for fusion jointing polyethylene systems—Part 1:Butt fusion GB/T 20674.2-2006 Plastics pipes and fittings—Equipment for fusion jointing polyethylene systems—Part 2:Electrofusion GB/T 20674.2-2020 Plastics pipes and fittings—Equipment for fusion jointing polyethylene systems—Part 2:Electrofusion GB/T 28799.2-2012 Plastics piping systems for hot and cold water installations—Polyethylene of raised temperature resistance(PE-RT)—Part 2:Pipes GB/T 28799.2-2020 Polyethylene of raised temperature resistance (PE-RT) piping systems for hot and cold water installations—Part 2:Pipes GB/T 28799.4-2024 Polyethylene of raised temperature resistance(PE-RT) piping systems for hot and cold water installations—Part 4:Valves GB/T 28799.5-2020 Polyethylene of raised temperature resistance (PE-RT) piping systems for hot and cold water installations—Part 5:Fitness for purpose of the system 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 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 29047-2021 Prefabricated directly buried insulating pipes and fittings with polyurethane foamed-plastics and high density polyethylene casing pipes GB/T 37827-2019 Welded ball valve for urban heating GB/T 37828-2019 Bidirectional metal to metal sealed butterfly valve for urban heating GB 50236-2011 Code for construction and acceptance of field equipment, industrial pipe welding engineering