KHIA headerKnow-How in Action

VOL XXVI, NO 44

Belzona® Repairs Water Jet Flange Area

 
 

Industry:

Marine (MRNE)

 
 

Application:

Valves, Pipes and Fittings (VPF)

 
 

Customer Location:

Naval shipyard, Vaxholm, Sweden

 
 

Application Date:

December 2011

 
 

Application Situation:

Rolls Royce water jet propulsion unit on combat boat built 2002. Total time in water almost 6 years.

 
 

Problem:

The water jet tunnel was suffering from cavitation and corrosion the flange holding the impeller housing in place. The most severe damages were found on the flange face and extended 20 cm inwards. Additionally the flange face was found to be distorted.

 
 

Products:

Belzona® 1111 (Super Metal)

Belzona® 1341 (Super metalglide)

 

Substrate:

Aluminium

 
 

Application Method:

Application was carried out in accordance with Belzona Know-How system Leaflets VPF-1 & 2. Flange face and cavitation erosion was rebuilt with Belzona® 1111. critical clearances were machined before applying Belzona® 1341 for overall erosion corrosion protection.

 
 

Belzona Facts:

This ship yard has previously used the same method for repairs on water jet propulsion units with great success. Belzona avoids hot work that could create further distortion and provides excellent corrosion and cavitation protection in water jet propulsion systems.

 
 

Photographs Description

  1. The damaged water jet unit
  2. A close-up of the damage
  3. Machining down the flange surface after rebuilding with Belzona® 1111 
  4. completed application after coating with Belzona® 1341
 
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