R Stamp Requirement :: Plate Heat Exchanger :: Addition of Plates

[srinivasakumar]

We have a Plate Heat Exchanger that is U stamped. We now intend increasing the heat duty by installing additional plates in the heat exchanger. The plates are manufactured by stamping ( pressing) and do not involve any welding. The installation is by Bolting and does not involve any welds. I would like to receive advice if this modification will require following the "R" stamp " Alteration" process?

 

[metengr]

At this point PHE repairs and modifications are not addressed by the NBIC. The NBIC committee, Part 3 has an action item that has been in review addressing PHE repairs and alterations.

 

[srinivasakumar]

Thank you very much Met Engr. After the modifications, I presume, the U stamp becomes invalid. What should we do under such circumstances? Please advise.

 

[metengr]

No, the U-stamp is a construction certification and stays with the vessel. I would record the activity on a Form R2 and keep it with the maintenance history of the vessel.

 

[srinivasakumar]

Dear MetEngr,

Thanks once again.

 

[srinivasakumar]

Dear MetEngr,
One more question. For the additional plates, is it enough for the supplier to furnish a Certificate of Compliance instead of U Part Report. As the plate does not involve any welds, is a certificate of compliance by the manufacturer adequate? I am reading NBIC Part 3 Section 3 Clause 3.2.2. Please advice.

 

[metengr]

Yes.

 

[srinivasakumar]

Thank you MetEngr. What form shall we use for the Certificate of Compliance? Should it be from NBIC or ASME Section VIII Division 1? Form R2 has a compliance section. But the part manufacturer in my project only has a "U" stamp. No "R" stamp. Please guide me.

I am preparing just in case my client wants to go for the R stamp process.

 

[metengr]

The Form R2 should be used with the Certificate of Compliance from the plate supplier. As I mentioned, you can fill out the Form as though it was an alteration and attach or reference the certificate of compliance from an ASME Certificate holder. This would be for information purposes until such time the NBIC provides specific requirements for addressing plate heat exchangers.

 

[srinivasakumar]

Dear MetEngr
Thanks very much. Certificate of compliance from an ASME Certificate Holder - Is this in a specific format available in Code? or is this in a format designed by the ASME certificate holder?

Please reply.

 

[metengr]

The Certificate of Compliance is based on the Quality Program of the ASME Stamp holder.

 

[srinivasakumar]

Many thanks.

 

[Compositepro]

Plate heat exchangers are designed to have a variable number of plates. Adding plates does not change any stress or forces on any parts. You may need longer tie rods, which are basically bolts. I would say that there is no need for concern, but check with the manufacturer.

 

[srinivasakumar]

Thank you Compositepro. The equipment has longer tie-bolts. Our concern was with the R stamp requirement. This is very clear now.