KHIA headerKnow-How in Action

VOL XXVI, NO 85

Belzona® Repair To Francis Turbine End Cover

 
 

Industry:

Power (POWR)

 
 

Application:

Centrifugal Pumps (CEP)

 
 

Customer Location:

Hydro power plant, Sweden

 
 

Application Date:

April 2011

 
 

Application Situation:

End cover of Francis turbine manufactured by KMW in 1939. This hydro plant is one of the main electric utilities in the country.

 
 

Problem:

The velocity of the water had led to erosion damage on the end cover of the turbine casing. Several through wall defects were reducing the efficiency of the unit. The end cover was 2.6m wide, 0.2m deep and 1.4 m long

 
 

Products:

Belzona® 1291 (ES Metal)

Belzona® 1311 (R-Metal)

Belzona® 1341 (Supermetalglide)

 

Substrate:

Cast iron

 
 

Application Method:

Application was carried out in accordsance with Belzona Know-How System Leaflets CEP-3 & 5. The work was done in the contractor’s workshop. After preparing the substrate by grit blasting and sealing holes with Belzona® 1291, Belzona® 1311 was applied up to a total thickness of 5-6 cm to restore original profile (100 kg of Belzona® 1311 was used for the repair on the two turbine ends). Finally two coats of Belzona® 1341 were applied to offer erosion protection and to create a smooth finish.

 
 

Belzona Facts:

Thanks to the previous experience and successful jobs done by the contractor in the hydro industry, and also previous succesful inspections, the Belzona solution was the chossen option for this application. Given the fast curing properties of the Belzona solution versus conventional solutions, the end cover was back on-site within a few days. 

 
 

Photographs Description

  1. One of the end cover halves (there are 4 in total) 
  2. View of the end cover after surface preparation. Through wall defects clearly visible 
  3. A former was used to create the original profiles  
  4. The application of Belzona® 1341 to complete the repair
 
Case study pic one

 

 
 Case study pic two

 

 
 Case study pic three

 

 
 Case study pic four

 

 
 
For more information about Belzona visit: www.belzona.com