Fastener traceability for PED

[jameshow]

For assemblies that use fasteners (in this example Hex Nuts) as main pressure bearing components according to PED, what's the general rule on traceability to the assembly and identification to the material certificate? All of my other components are marked, identifiable and traceable, but to do the same thing for hex nuts becomes incredibly cumbersome. I know a 3.1 certificate is required, but is marking each nut with a heat/batch code also necessary, or can I use inventory control to give me a good estimate at which assemblies used which batch of fasteners?

Thanks,
James

 

[XL83NL]

There's a guideline on the mtr* requirements for fasteners. A 3.1 is not (always) required.

Wrt traceability, Im pretty sure its sufficient if you file all mtrs in one document/folder/binder, as long as that document stays traceable to the specific pressure equipment. The PED does not specify you have to be able to track down each mtr to each fastener.

I dont have a copy of the PED in front of me so I can detail the specific parts of the PED to justify my point of view. But this is how we do it, and so far, its always been accepted by both our clients and notities bosjes that were involved.

If you use EN 13480, you may find additional details though. So far, ive assumed B31.3 as the design code.

*mtr=material test report, i.e. certificate.

 

[OSIRIS7]

PED requires that ALL pressure bearing materials are traceable. The practical problem however is marking. Se PED guideline 7.4.

3.1 at least is required for cat. II, III and IV equipment.

See also PED Guideline 7.8

I know from practical point of view that it is allowed to receive a bundled lot of bolts or nuts and the certificate is valid for the box/crate. Once out of the box, the traceabilty is gone. Which means that you can use these bolts out of the box, but re-using bolts and nuts is the tricky part however.

Maybe AD Merkblatt W7:2007 gives you some more guidance.