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Sf6 Gas Leaks Sealed With Belzona



Power (POWR)



Tanks and Chemical Containment Areas (TCC)


Customer Location:



Application Date:

October 2012


Application Situation:

Gas insulated electricical switchgear



Failure of the original sealant between the bolted flanges had resulted in loss of containment of the insulating SF6 gas, a potent greenhouse gas.



Belzona® 2221 (MP Fluid Elastomer)



Mild Steel


Application Method:

Application was carried out using a modified version of Belzona System Leaflet TCC-1. The equipment operator lowered the pressure inside the equipment prior to the application. The area was thoroughly cleaned and roughened before the flange and bolts were completely encapsulated with the Belzona® 2221 focusing on the gap between the bolted faces. Once cured, the equipment was re-pressurized and tested for leaks.


Belzona Facts:

With no other alternatives, the national energy supplier turned to Belzona to seal these leaks. The Belzona Distributor, Beltech, successfully sealed 95% of the leaks on this initial application with the remaining 5% inaccessible due to equipment design. The dramatically reduced gas losses resulted in massive cost savings to the client, reduced environmental impact  and has led to further applications in these areas.


Photographs Description

  • Bolted joints prior to application 
  • Surface Preparation carried out using a disc grinder and solvent cleaning  
  • Joints sealed with Belzona® 2221 coating 
  • Bolts were also encapsulated, completely stopping leakage of SF6 gas in all accessible areas
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