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vessel ASME built to PED

vessel ASME built to PED

vessel ASME built to PED

(OP)
the pressurevessel is built unther ASME, and also tested unther this code.
Now they want to have this vessel accoording the PED,
What steps do I have to take, regarding the pressuretest?

RE: vessel ASME built to PED

The pressure test may be the easiest part - see Annex I Paragraph 7.4 of the PED. Minimum test pressure will be 1.43 x max allowable pressure.

You may have bigger problems though if the vessel is already built without consideration of the requirements of this directive. It is certainly Ok to design and build to ASME, but unless the vessel is classed as "SEP" then there are declarations to be made, certifications by a Notified Body, and CE marking to be done. That's all described in the PED, and ASME also has a guide for Stamp Holders that details requirements.

All the best,
John

RE: vessel ASME built to PED

This question has been asked many times on the ASME forum (http://www.eng-tips.com/threadminder.cfm?pid=292) and I think also in the CEN forum (http://www.eng-tips.com/threadminder.cfm?pid=748).

Do a search.

There are two calculations for the pressure test, either 1.43 x design pressure or 1.25 x design pressure x ratio of allowable stresses at ambient and design temperature.

The first issue is to determine what classification the vessel falls under, if it is SEP then it is outside the scope of the directive and a simple declaration is all that is necessary, you don't even have to do any extra pressure testing. If it falls under any other classification then you have to agree an appropriate module with the customer and, for anything other than Module A, obtain thye services of a Notified Body.

RE: vessel ASME built to PED

Fawkes,
       Not sure you are correct when you say that if the vessel is SEP then it is outside the scope of the directive. SEP is a classification within the directive NOT outside the directive. Only if the pressure is less than 0.5 Bar can the vessel be "outside the directive".

5050505050, (Hope there are enough "50",s)
            Basically you have to ensure the vessel meets the ESR's (Essential Safety Requirements) listed in the Directive. Also all materials must used must be "approved" for use in accordance with the directive. This could be a sticking point if the vessel is complete as you could well need toughness certification for the material. If you ae/have used ASME materials then you may need to apply to the NoBo for acceptance of the material via Particular Material Approval route.  

RE: vessel ASME built to PED

SEP isn't a classification within the directive, vessels that fall outside of the scope of the directive must be designed and manufactured to Sound Engineering Practice and that is where the term comes from.

 

RE: vessel ASME built to PED

Just as an addition to that last comment, we haven't currently identified a way of constructing a vessel to Sound Engineering Practice without following the same rules and considerations as a vessel produced to the PED so they end up being produced to the same criteria but some have a CE mark and some don't...

RE: vessel ASME built to PED

Fawkes,

I'd have to agree with DSB123 regarding the SEP classification being within the scope of the directive. Article 1 Paragraph 1 is clear on the applicability of the directive to pressure equipment with PS greater than 0.5 bar.

I also agree with your last statement - shops familiar with or always working to the PED would not drop their standard of work for an SEP vessel - it's the weight of paper that may change.

Getting back to the OP, an SEP classification would likely be the easiest way to dig himself out of the hole he is in, if the vessel is already built. Otherwise, the next best chance of a nice outcome is if any 3rd party inspection carried out on the vessel was done by someone who is also a Notified Body.

RE: vessel ASME built to PED

Fawkes,
       You are correct SEP is not a "classification" within the PED, however it is a category within the PED. Have a look at the graphs within the PED Directive and you will see that all have SEP area indicated - hence SEP is a "category" within the PED. The only difference is that a NoBo is not involved for SEP "Category". Lets be clear if a vessel falls outside the PED Directive (Pressure less than 0.5 Bar) the Directive does not apply and hence cannot dictate that Sound Engineering Practice must be used for the design as you suggest. Vessels which fall within the PED (i.e pressure greater than 0.5 bar) and are categorised as being SEP need to be designed to Sound Engineering Practice.

RE: vessel ASME built to PED

I'm not quite sure if SEP is or isn't within the scope of the directive after reading it again.

I think, on reflection it could conceivably be in as much as there is a legal requirement under Article 3 Paragraph 3 to construct the equipment within Sound Engineering Practices of a Member State, this legal requirement could imply that the vessel falls within the scope while the insistence that the equipment cannot bear the CE mark allows you to draw a different conclusion.

In this instance I think I'll bow to the most common interpretation ;o)

RE: vessel ASME built to PED

SEP is withing the scope of the directive, but under the threshold for Category 1. The really big difference is you are NOT allowed to CE mark SEP vessels. You can reference the PED directive and paragraph on a label, but you can not apply the CE mark.


As for how to meet it, you should be able to use ASME, which has been recognized for many years in many of the member states. See excerpt below from PED Guideline 9/17:

Question: How shall a manufacturer established outside the European Economic Area (EEA fulfil the requirement of the sound engineering practice (SEP) of a Member State ?
Answer: A manufacturer outside of EEA may choose the SEP of one of the Member States.
SEP from countries outside EEA does not automatically fulfil the requirement of Article 3, paragraph 3.
However, as a general rule, it can be assumed that the SEP of a Member State is met if :
- the product has been legally marketed in one Member State of EEA for many years, or
- the product fulfils technical specifications recognised by one Member State of EEA.  
 

RE: vessel ASME built to PED

So what's the story 5050505050? Have you checked to which category the vessel is to be classified? As discussed already in this thread, that will determine how difficult this exercise will become for an already fabricated vessel.

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