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Belzona® Relief Valve Repair



Power (POWR)



Mechanical Power Transmission (MPT)


Customer Location:

Hydro Electric Generating Station - Scotland


Application Date:

August 1998


Application Situation:

The sealing surface on the pressure relef valve had suffered damage and water was passing causing the valve not function properly.



Previous attempts to weld similar equipment had resulted in the brass piston distorting and so an alternative method for repair was sought.



Belzona® 1111 (Super Metal)





Application Method:

Application was carried out in accordance with the Belzona Know-How System Leaflet MPT-1. Damaged area was machined out, filled with Belzona® 1111 then machined to tolerance.


Belzona Facts:

The difficulty of weld repairing similar jobs previously had led to lost time and missed deadlines. Written report received from client confirming Belzona repair in good condition and suitable for return to service after already completing 9 years service.


Photographs Description

  1. Piston being machined out.
  2. Belzona® 1111 machined to tolerance.
  3. Valve in for overhaul in 2007. This had nothing to do with the original Belzona repair.
  4. Belzona in good condition and was returned to service with no work required after passing offsite hydrostatic testing and onsite commissioning.
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