Delivery Conditions N and Q of Pipeline

[_1angelia23]

Hi, dear engineers

We have an oil and gas processing project, we requested the supplier to provide us with two oil trunk lines 16".
their specifications are API 5L PSL2 X52NS SAWL, but the supplier requested changing N condition to Q condition to be able to manufacture them since they can not produce them in their mills by the condition N .
I am trying to understand if that has any imapact on our trunk lines and what are the differences between N and Q conditions

Thank you in advance

 

[LittleInch]

That's what metalurgists are employed for to look at the whole spec and advise you.

Find one.

 

[SJones]

N = Normalised; Q = Quenched & tempered. That gives you a couple of terms to chat to Copilot with.

Q will have an extra heat treatment step which will occupy purchaser inspection at the plate mill should such inspection actually be deployed. In general terms, Q may have better sour service performance. If post weld heat treatment is required during pipeline construction, Q will require tighter control on temperature.