Products FAQ
Can A516Gr70 pressure vessel steel plates be used in hydrogen sulphide (H₂S) environments?
Yes, provided that HIC/SCC (hydrogen-induced cracking/stress corrosion cracking) testing is carried out.
Does A516Gr70 steel plate require post-weld heat treatment?
Thickness ≤50 mm: Not mandatory, but recommended for critical welds.
Thickness >50 mm or for use in hydrogen sulphide or wet corrosion environments: Post-weld heat treatment is mandatory to eliminate residual welding stresses and prevent hydrogen-induced cracking.
Can A516Gr70 steel plates be used for cryogenic tanks?
Yes, A516Gr70 steel plates are suitable for the manufacture of LNG, LPG and liquid nitrogen storage tanks, but must undergo impact testing at -40°C/-46°C as required.
Must A516Gr70 boiler and pressure vessel steel plates be supplied in a normalised condition?
Yes, the standard mandates that they be supplied in a normalised condition.
Normalising: Heating to 30–50°C above Ac3, followed by air cooling, to refine the grain structure, relieve internal stresses and significantly improve low-temperature toughness.
Hot-rolled or controlled-rolled conditions cannot consistently meet impact requirements and are not a substitute for normalisation.
What is the applicable temperature range for ASTM A516 Grade 70 boiler and pressure vessel steel plates?
Standard Safe Temperature Range: -29°C to 343°C
This is the range recommended for long-term stable operation in engineering design. Within this temperature range, the mechanical properties of the material (such as strength and toughness) can be reliably guaranteed.
Extreme Temperature Limits: -46°C to 538°C
Lower Temperature Limit (-46°C): By using steel plates supplied in the normalised condition (commonly referred to as Gr.70N), the material can meet impact toughness requirements down to -46°C.
Upper Temperature Limit (538°C): According to ASME codes, the maximum permissible service temperature for this material in non-corrosive environments is 538°C.
