Designed to ASME have to erect in PED controlled area

[QCJT]

Hello respected specialists,

We have our standard piping design according ASME norms and the client is in one of EU countries where PED norms apply. The client who will do the welding has all of his procedures and welders qualified according EN norms and if they have to now requalify everything to ASME it will consume awfully lot of time and money. So does anybody know if we can somehow avoid this and use our ASME design but still be ok according to PED?

Thanks in advance
JT

 

[XL83NL]

Strictly, I would go for a full/100% ASME compliant design, and check if that meets PED. It's actually quite easy to squeeze a B31.3 design under the PED. You may wish to review CEN/TR 14549:2004 en.

However, if youre willing to go the route you mentioned, the design will never comply with ASME. It can comply with the PED, but now youre mixing up Codes. Regardless if your client/contract allows this, I wouldnt go there. I guess someone made an error somewhere down the line and now someone else needs to clean up.

 

[QCJT]

Thanks XL83NL!

It was an interesting read. After talking to authorities coordinator, I have the feeling that the problem isn't that big as PED seems to be flexible to accept ASME design because it's usually higher wall thickness than EN. However, NDT requirements in EN are more stringent and therefore these will need to be applied.

 

[XL83NL]

However, NDT requirements in EN are more stringent and therefore these will need to be applied. [/quote} Why is that?

 

[QCJT]

PED is Ok if you design according ASME as it gives more wall thickness and therefore doesn't harm but NDT acceptance criteria under EN norms are more stringent. So naturally they want EN norms to be used for that.

 

[XL83NL]

Actually, for piping EN 13480 isnt that stringent, especially when youre considering it uses the PED category as one of the basis for determining the required NDE to be performed.

However, there's a difference between

NDT requirements in EN are more stringent and therefore these will need to be applied

and

So naturally they want EN norms to be used for that

I would opt for going either all the way B31.3, or all the way EN13480, but dont mix up. When applying PED, that's when it gets tricky (and not when you go for full B31.3 w/ PED, even though B31.3 isnt a harmonized standard).

 

[DekDee]

QCJT,
XL83NL has given sound advice.
The PED is a set of rules / guidelines - it is not a design code.
If you design to an EN norm then your NDT requirements are governed by that code / standard.
If you have designed in accordance with ASME (eg. B31.3) and that has been accepted by the client then your NDT requirements are based on ASME B31.3 - irrespective of what EN may or may not require.
Regards,
DD

 

[QCJT]

Thank you guys for your input.

DekDee, I am not sure about that last line of yours. PED allows mixing if you are choosing a more stringent standard/norm but not other way around. So IF ASME is less stringent than EN norms in NDT requirements then PED demands you to follow EN norms. The question wasn't about ASME B31.3 in particular but rather general, it's not only piping but also static equipment that I'm talking about.
Regards,
JT

 

[XL83NL]

Well, technically, you may be right; see guideline 9/6. But when the big bang happens and you're at the fence in court, trying to explain the judge why you mixed up codes, you'll have a very small chance this guideline will give you an escape. Think about that.