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PED certified vessel head

PED certified vessel head

PED certified vessel head

I am trying to locate a 2:1 elliptical head for a pressure vessel that needs to be PED certified. I'm having trouble tracking down a manufacturer that has PED capebilities or even knows what PED is. The other issue with this piece is that it needs to be about 7/8" thick (16" OD) which is pretty demanding of many head formeres before I even get to ask about PED.

One company said they are able to form the heads but didn't seem to understand what I meant by PED. Does EN104 mean anything related to this certification?

If anyone knows of possible certified suppliers of vessel heads, I would greatly appreciate the information.

RE: PED certified vessel head

The manufacturer of the head does not need to have any knowledge of the PED, the PED is for vessels and pipe work.

It is the manufacturer of the vessel or the pipe work assembly that must comply with the PED.

The head needs to be produced to an acceptable standard (such as B16.9) and the manuafcurer of the head and the raw material needs to have an ISO quality assurance system approved by an appropriate body with a presence in the EU.

Here si the direct quote from Annex 1 4.3


The equipment manufacturer must take appropriate measures to ensure that the material used conforms with the required specification.
In particular, documentation prepared by the material manufacturer affirming compliance with a specification must be obtained for all materials.
For the main pressure-bearing parts of equipment in categories II, III and IV, this must take the form of a certificate of specific product control.
Where a material manufacturer has an appropriate quality-assurance system, certified by a competent body established within the Community and having undergone a specific assessment for materials, certificates issued by the manufacturer are presumed to certify conformity with the relevant requirements of this section.

Check out the faqs, especially http://www.eng-tips.com/faqs.cfm?fid=281 as this links directly to the PED offical site where you can get a copy of the PED.

RE: PED certified vessel head

Fawkes, thanks you for your reply. The requirements we follw for our PED vessel components are:

1)       The mill must hold ISO 9000 certification issued by a registrar resident in the European Community.

2)       In addition to the material specification, the requirements of a. or b. must be met:

a.       Original Manufacturer’s Material certs must show conformance to EN10204-3.1B and the ISO Certification, or

b.       The manufacturer must supply a copy of the ISO 9000 Certificate with the original manufacturer’s material certs.

3)       Original Manufacturers material certs must contain (or be accompanied by a document that contains) a statement that the material is in compliance with the material specification.  

We assume the 'mill' to be the last process performed to the material involving heat application. In the case of a 7/8" thick head, I would assume Hot Forming would be required and the the head manufacturer would then become the 'mill'. Am I still going in the wrong direction with this?

RE: PED certified vessel head

That all seems OK it is just that the manufacturer of the head doesn't have to concern themselves with the PED and that's why they don't know anything about it, the requirements you've set are all you need to tell them.

RE: PED certified vessel head

Thanks again for all the help. I have sent that information to a few suppliers I know of. Hopefully we can work it out. So glad thats been clarified!

RE: PED certified vessel head


If they are hot-formning the heads then you have to address the question of whether they changed the mechanical properties. If so, then the head manufacturer rather than the mill becomes Material Manufacturer and they may have to retest after forming. It all depends on if mechanical properties are changed, and the PED does not give a lot of guidance here.

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