Reference Standards
ASME B16.9 Factory-Made Wrought Steel Buttwelding Fittings
ASME B16.28 Wrought Steel Buttwelding Short Radius Elbows and Returns
ASME B16.25 Buttwelding Ends
MSS SP-43  Wrought Stainless Steel Butt-Welding Fittings
MSS SP-75  High-Test, Wrought, Butt-Welding Fittings
ASTM A234 Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature
ASTM A860 Wrought High-Strength Low-Alloy Steel Butt-Welding Fittings
ASTM A420 Piping Fittings of  Wrought Carbon Steel and Alloy Steel for Low-Temperature Service
ASTM A403 Wrought Austenitic Stainless Steel Piping Fittings
ASTM A960 Common Requirements for Wrought Steel Piping Fittings

DIN 2605-1 Steel butt-welding pipe fittings:Elbows and bends with reduced pressure factor
DIN 2605-2 Steel butt-welding pipe fittings:Elbows and bends for use at full service pressure
DIN 2615-1 Steel butt-welding pipe fittings:Tees with reduced pressure factor
DIN 2615-2 Steel butt-welding pipe fittings:Tees for use at full service pressure
DIN 2616-1 Steel butt-welding pipe fittings:Eccentric reducers with reduced pressure factor
DIN 2616-2 Steel butt-welding pipe Reducers for use at full service pressure

GB/T12459  Steel butt-welding seamless pipe fittings
GB/T13401 Steel plate butt-welding pipe fittings
SH3408 Steel butt-welding seamless fittings
SH3409 Steel plate butt-welding  fittings
SY/T0609 Specification for high test wrought butt welding fittings (MSS SP 75,MOD)