KHIA headerKnow-How in Action


Cold Bonding With Belzona® Offered Alternative Repair To Penstock



Power (POWR)



Gaskets, Seals and Shims (GSS)


Customer Location:

Hydro Power station, UK


Application Date:

March 2006


Application Situation:

Penstock of the hydro power station (the penstock support was half way up a hill).



The penstock had been weld repaired and due to the nature of hot works, the penstock had deformed and created a void between the penstock pipe and the concrete support pad. The Hydro power station would not accept the void between penstock and the pipe support and informed the contractor they would need to rectify the problem before signing the job off.



Belzona® 1211 (E Metal)

Belzona® 5811 (Immersion Grade)



Steel pipework


Application Method:

Application was carried out in accordance with Belzona Know-How System Leaflet GSS-9. Edges of brass plate were sealed to penstock with Belzona® 1211. Void between penstock and plate was then filled with Belzona® 5811 using injection equipment. 


Belzona Facts:

The repair was done on site, in a short time. The injection technique used in this application ensured that there is no void between the brass plate and the penstock, eliminating any galvanic or crevice corrosion. Belzona application remained effective until entire penstock had to be replaced.


Photographs Description

  1. View of the penstock
  2. View of the pipe support 3. Brass plate being put into place
  3. Application completed (Belzona® 1211 on the edges, Belzona® 5811 injected in the void)
Case study pic one


 Case study pic two


 Case study pic three


 Case study pic four


For more information about Belzona visit: