Particular material appraisal 1

[laphroaig]

Has any one has succes with particular material appraisal, PMA, acc to PED. I'm mostly intrested in US materials as A-105, A-106 grB A-234 WPB etc.

Please share your experiance

JH

 

[abbver98]

There is an official form of the PMA edited by the CEN. Hereafter the content of the form:

Particular Material Appraisal

PMA Ref. No. :
Pressure Equipment Manufacturer :
Application :
Material Specification :
Thickness Range :
Max. Allowable Pressure :
Max. Allowable Temperature :
Min. Allowable Temperature :
Design code :

Compliance with Essential Safety Requirements :

Property Requirement Compliance
Appropriate Properties Allowable stress at 250°C Rm/20
Sufficiently Ductile A%
Sufficiently Tough 27J at 20°C or lowest operating temp.
Not Significantly Affected by Ageing At intended operating temperatures
Suitable for Intended Processing Machinability Forming Welding
Type of Certificate Cat. II, III, IV : -3.1.B
Material Manufacturers Approval ISO 9000 by Euro. Accredited Body

Additional testing results are given in Test Report No :

Where selected to be sufficiently chemically resistant to the fluid contained and to avoid significant undesirable effects when the various materials are put together, the named material specification may be used for the construction of the pressure equipment intended for use within the stated limits and subject to the following restrictions :

Restrictions :
Additional Testing :

Signed : Date : 1


Approved : Date : Notified Body No.:
Reviewed First issue
Approved N.A.
I can e-mail it you.
Note that you have to check the material according to the annex I-4. See correspondants guidelines.
For cat. III and IV PMA must be performed by NB.
I did PMA for A-105, A-106 and A-216 WCB.

 

[gunnarhole]

I am also confused about the materials that can be used in PED vessels. For example can I use ASTM A 516-70 plate, A-106B pipe, and A-105 flanges?

From what I can see on the PED site, allowable materials must be either:

1. produced to a harmonized standard (of which we have EN 10028, 10213, and 10222 and these, we are warned, may not comply)

2. have received a EAM certificate (of which none of those applied for have yet to be accepted)

3. have received particular approval (for which the guidelines are being prepared)

It looks like a PED vessel is going to be tough to find material for, unless you are in Europe.(question - Have the common ASTM and JIS grades, like those above, been grandfathered" into the harmonized standards?)

Why would anyone (not legally obligated to) want a PED Vessel vs. a B5500 or ASME VIII design? Is it cheaper? Is it safer? Can I repair/modify it if I need to? Will the documentation weigh more than the vessel? I guess you can put me in the "wait and see" category for now.

Regards,

Gunnar

 

[gunnarhole]

Fawkes,

As you say, perhaps I have misunderstood the intent of the PED.

As an example, let's assume a horizontal API type separator, designed to handle an oil/water/gas mixture at 10 bar and 50 C. Let's also assume that the materials of construction are ASTM A105/106B/516-70. Let's also assume it's going to be fabricated in an ASME Code approved shop.

What supplementary documentation would be required by the PED in order to receive approval to use this vessel in Europe. I mean those documents above and beyond what would be provided for an ASME VIII vessel. I understand from your previous post that completed PMA's "certifying" that each of the materials selected were appropriate for the design conditions would be required. What other documents would need to be filed?

I understand that the philosophy of the PED is a noble and wondrous thing. I just want to know how to buy and use one without employing a consultant from Brussels.

Regards,

Gunnar

 

[laphroaig]

Fawkes, Gunnarhole

You can use material from almost any code
If you can convince your notified body (NB)that the material fulfil the essential safety requirements (ESR) of Annex 1.The NB makes a PMA.
For the rest of fabrication the notified bodies don't have the same acceptance over Europe. It has been deliverd CE markt vessels, made acc. to ASME, and only ASME! in some memberstates, but I would not think this possible in i.e. Scandinavia.
Unfortunaly you may have to choose "right" NB for your way of fabrication.

 

[abbver98]

I put in this address an official PMA :

http://home.tiscali.be/pvessel/Appraisal-Blank.PDF

I'm preparing program for PED classification and technical requirements to fulfilled.

 

[michaelaston]

The contribution made by abbver98 on Aug 23, 2002 was very helpful. Can someone please send me a copy of the official PMA form. It was mentioned that it was edited by the CEN does anyone know who originated it. Also whether the Notified Bodies have adopted it? Having received a copy of a PMA from one of the major notified bodies prior to Aug 2002 some of this information was missing from their document. However their document included "formability" which seems to have several different definitions.

Michael