API 5L plate?

[HgTX]

What does it mean to order or roll plate to API 5L Gr. X65? It's a pipe spec. Does it mean following everything except the welding and dimensional requirements? I would have thought there would be a separate plate spec and then the pipe spec would specify that plate.

Also I can't find in 5L anything about metallurgical process, whether the steel is killed, etc., or whether it is Q&T. Am I missing it? Is it not there? Is it somewhere else?

Hg

Eng-Tips policies: faq731-376

 

[ulyssess]

It is a usual procedure, that plates are delivered according API 5L to pipe manufacturers. Generally, additional requirements are stipulated, e.g.
- dimensional tolerances for the plates
- restricted chemical composition adjusted to the planned welding conditions
- modified minimum values for mechanical properties to take into account the modifications caused by cold forming to pipes, eventually followed by expanding.
- test requirements (mechanical, NDT)
There are no specific standards for the delivery of plate material as starting material for pipe production.
A lot of metallurgical processes are defined in new 2007 edition of API-5L.

 

[HgTX]

So if someone tells me they have 5L X65 plate that they want to use instead of what I specified, do I really know anything about that plate from the spec, or do I need to demand specific MTRs?

Hg

Eng-Tips policies: faq731-376

 

[ulyssess]

What did you specify?
Intended application?

 

[HgTX]

Structural plate, ASTM A 709 Gr. 50 (like ASTM A 572). 5L includes chemistry, CVN, tensile properties, so I'd think I'm okay, except that really 5L applies to pipe, not plate, so I don't really know what the mill's under obligation to provide.

I'll go by the individual MTRs if I have to, but if it's a lot of plates (I don't know yet), that could get tedious as compared to just basing the decision on the material spec.

Hg

Eng-Tips policies: faq731-376

 

[ulyssess]

X65 can match the requirements of ASTM A 709 Grade 50. Nevertheless, some details should be verified on MTRs:
1) Elongation: In API 5L, elongation may be measured either on rectangular or on round tension test specimen. If a rectangular specimen is used, this specimen must be 1.5 inch wide, but gauge length is 2 inches. This gives rather high values ( > 30%), but is not in accordance of ASTM A709.
2) X65 may be delivered as PSL1 without impact requirements
3) Mn may be up to 1.75% (ed. 2007) resp. 1.65% (ed.2004), not allowed in A 709-50 (max. 1.60)
4) Testing frequency may not match the requirements of A 709