OVERVIEW: 30 year old cast iron Guide Vanes were suffering from severe corrosion resulting in metal and sealing face loss due to SRB causing deep pitting corrosion. We recommended rebuilding with our RB 300 series, a glass flake filled vinyl ester coating providing an abrasion/corrosion resistant impermeable barrier to provide long term protection in this environment
INDUSTRY
Power Generation – Hydro
ENVIRONMENT
Fresh water
SUBSTRATE
Cast Iron – 20-30 years old
CHALLENGE
Guide Vanes were suffering from severe corrosion resulting in metal and sealing face loss due to SRB causing deep pitting corrosion
SOLUTION
We recommended rebuilding with our RB 300 series, a glass flake filled vinyl ester coating providing an abrasion/corrosion resistant impermeable barrier to provide long term protection in this environment
SCOPE
Pre machine reference points to enable final dimensions to be obtained
Abrasive blast to AS 1627.4, 75 µm nominal profile
High Pressure hot wash to assist with the removal of metallic salts and re abrasive blast to the above standard
Mask and protect all surfaces not to be damaged during the application process
Application of RB 300 Primer
Pit fill and re-profile surfaces to original dimensions
Carry out QA including high voltage spark test, i.e. 10kV to ensure no voids are present
Post machine critical dimensions, detect and rectify defects
PRODUCTS
OUTCOME
Chemcote was able to refurbish the guide vanes within the strict time-frame requested by the client. This application will provide at least 15-20 years of corrosion free service
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