HG/T 20538-2016 Selection series of plastic-lined pipe and fittings

GB 11115-1989 Low density polyethylene resin GB/T 11115-2009 Polyethylene(PE) resin 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 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 5117-1995 Carbon steel covered electrodes GB/T 5117-2012 Covered electrodes for manual metal arc welding of non-alloy and fine grain steels 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 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 8923.2-2008 Preparation of steel substrates before application of paints and related products—Visual assessment of surface cleanliness—Part 2:Preparation grades of previously coated steelsubstrates after localized removal of previous coatings GB/T 8923.3-2009 Preparation of steel substrates before application of paints and related products—Visual assessment of surface cleanliness—Part 3:Preparation grades of welds,edges and other areas with surface imperfections 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 GB/T 12459-2025 Steel buttwelding piping fittings—Types and parameters