THE PROBLEM
The stainless steel chemical tank was leaking from an unknown location. A seamless tank lining that would also withstand the operating temperature and aggressive sodium hydroxide was required.
SOLUTION
Stainless steel is a notoriously difficult surface to adhere to when relining a tank . To create the mechanical profile required for our tank lining the stainless steel was prepared by method of abrasive blasting.
To test that sufficient profile had been achieved checks were undertaken using a surface profile needle gauge.
Preparing the tank internals for the replacement tank lining
Once prepared the tank internals were thoroughly vacuum cleaned, in order to remove any dust contamination which would be detrimental to the adhesion of the new tank lining.
Selecting the correct tank lining from Chemco International
The selected tank lining was a high quality glass flake reinforced vinyl ester from Chemco International.
To assist with adhesion to the stainless steel, the first coat of the three coat tank lining was Chemco RC300. This vinyl ester offers improved adhesion to difficult substrates such as stainless steel.
The tank lining process
As per good tank lining practice separate stripe coats were applied at each stage of the tank lining process.
Following the cure of the RC300 vinyl ester, two further coats of Chemco RA300 were applied to achieve a total tank lining thickness in excess of 1000 micrometers.
Regular wet film thickness readings were taken during application and dry film readings between coats.
To ensure a defect free finish the tank lining was tested for pin holing using a DC holiday spark tester. Where found these were marked and rectified using the same material.