SA 516 Gr 70, Tempering Temperature
SA 516 Gr 70, Tempering Temperature
(OP)
Recently I came across some SA 516 Gr 70 NACT(nornalized + Accelerated cooled + tempered) plates from some reputed mill where tempering temperature is indicated as 590 Deg in MTC.
As per SA 516 Gr 70, section 5.4
If approved by the purchaser, cooling rates faster than those obtained by cooling in air are permissible for improvement of the toughness, provided the plates are subsequently tempered in the temperature range 1100 to 1300°F [595 to 705°C].
Supplied plates have been certified as SA 516 Gr 70 by the mill and accepted by inspection agency including AI even though tempering was carried out at 590 Deg
Am I missing some thing here??
As per SA 516 Gr 70, section 5.4
If approved by the purchaser, cooling rates faster than those obtained by cooling in air are permissible for improvement of the toughness, provided the plates are subsequently tempered in the temperature range 1100 to 1300°F [595 to 705°C].
Supplied plates have been certified as SA 516 Gr 70 by the mill and accepted by inspection agency including AI even though tempering was carried out at 590 Deg
Am I missing some thing here??





RE: SA 516 Gr 70, Tempering Temperature
RE: SA 516 Gr 70, Tempering Temperature
Now, disposition of the nonconformance is rather simple, if the MTR indicates compliance with the minimum stated mechanical properties and CVN requirements for SA 516 Grade 70 and client requirements, the plate can be accepted.