1) Stainless steel seamless steel pipe implements GB/T14976-2012 "stainless steel seamless steel pipe for fluid transportation", requiring P≤0.035%, thereby limiting the use of intermediate frequency furnace to produce stainless steel seamless pipe blank, intermediate frequency furnace for dephosphorization needs additional ferronickel and ferrochrome; Hydraulic tests or eddy current flaw detection, intergranular corrosion inspections are required to ensure product quality.
2) Duplex stainless steel seamless steel pipe implementation GB/T20833-2008 "austenitic-ferritic duplex stainless steel seamless steel pipe", the main grades are: S22253, S22053, S25073; Hydraulic test or eddy current flaw detection, flattening test, flaring test are required to ensure product quality; It is stipulated that the tissue should be austenite and ferrite, and the austenite content should account for 40%-60%.
3) Stainless steel welded steel pipe implements GB/T12771-2008 "stainless steel welded steel pipe for fluid transportation", which requires weld ray detection, hydraulic test or eddy current flaw detection, intergranular corrosion test, flattening test, weld transverse bending test to ensure product quality.
4) Duplex stainless steel welded steel pipe implementation GB/T20832-2008 "austenitic-ferritic duplex stainless steel welded steel pipe", the main grades are: S22253, S22053, S25073; Weld ray testing, hydraulic test or eddy current flaw detection, flattening test, weld transverse bending test are required to ensure product quality; It is stipulated that the tissue should be austenite and ferrite, and the austenite content should account for 40%-60%.
