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Corroded Flange Grooves Reformed With Belzona



Power (POWR)



Valves, Pipes and Fittings (VPF)


Customer Location:

Hydropower plant, Switzerland


Application Date:

February 2012


Application Situation:

Flange grooves in four pipe flanges. Each flange had a diameter of 1820mm; the grooves were 16mm wide and 3-4mm deep.



Corrosion leading to incorrect sealing of mating surfaces



Belzona 1111 (Super Metal)

Belzona 1321 (Ceramic S-Metal)





Application Method:

Application was carried out in accordance with Belzona System Leaflet VPF-1. After grit blasting the groove, Belzona 1111 was packed overthick into the groove and, using a simple pre-cut template, the original profile of the groove was recreated. Finally, a thin layer of Belzona 1321 was applied to create a smoother surface.


Belzona Facts:

Welding would have taken three to four weeks for two people to complete, a considerable delay in the refurbishment of this hydropower plant. The simple and cold-applied Belzona solution was carried out in just six working days by three people and now ensures long-term corrosion protection of the liner grooves.


Photographs Description

  1. General view of the equipment before application 
  2.  A pre-cut template allows for simple, effective defining 
  3. Belzona 1321 applied for a smoother surface 
  4. Pressure pipe after re-assembly
Case study pic one


 Case study pic two


 Case study pic three


 Case study pic four


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