Weld repairs by belzona 1

[mariolucas75]

Dear Forum,

Are pressure vessel corroded / pitted welds repaired by belzona ?
Is there any threshold pitting / corrosion metal loss in weld up to some value to be repaired by belzona and after some threshold by belzona?

Thanks

 

[FacEngrPE]

Belzona can not be used to restore strength of a pressure vessel. It may be used as a corrosion or wear resistant coating on a pressure vessel.

Recommendation - have the pressure vessel surveyed in accordance with the Nationaionl Board Inspection Requirements by your AI. Make required repairs. Then apply Belzona (or any other coating).

It is possible the coating may need to be removed for the next inspection, you should ask your AI.

 

[Krausen]

Ah, welcome to Pandora's Box....When you ask about Belzona, you must be specific on which Belzona product. There are dozens of types. Typically, when people say "Belzona", they're referring to an epoxy type coating (typically internal coating) used for corrosion protection. However, Belzona does offer some metallic repair paste-type products that can be used in certain situations on PVs with pitting and/or local corrosion. There are temperature limits though on these, so this one major caveat. Engineers are always gun-shy to recommend or endorse these types of repairs, but it's been applied successfully more than most engineers want to admit, especially to restore pitted flange surfaces (these Belzona metallic repair products are machinable).

 

[chicopee]

If I remember correctly, pits depth of more than 50% of wall thickness should not be repaired per NBIC.