The stainless steel tank was leaking as a result of the breakdown of the rubber lining and chemical attack of the tank structure.
We proposed a new glass flake reinforced vinyl ester tank lining from Chemco International as the best solution.
Removing the rubber lining with high pressure jetting
Initially the existing rubber lining was removed using our Ultra High Pressure Water Jetting Unit to expose the stainless steel tank structure.
A soluble salt test was conducted to ensure that no soluble metal salts were present on the surfaces to be coated. This is essential when lining tanks which have previously been exposed to chemical immersion as soluble salts if present can draw moisture through the new tank lining, resulting in osmotic blistering and premature tank lining failure.
Abrasive blasting the stainless steel
Following the clear salt test, the stainless steel was prepared by method of abrasive blasting, to provide a clean surface and raise a surface profile to ensure excellent adhesion of the new tank lining. The blast profile was checked using a surface profile needle gauge.
Perforations exposed were repaired by the clients in house engineers.
All surfaces were vacuumed clean and the cleanliness of the steel tested prior to the application of Chemco RC364. This material is specifically designed to offer better adhesion to stainless steel – a notoriously difficult surface to adhere tank linings to.
Two further coats of Chemco RB332 was then applied to achieve a nominal lining thickness of 1000 micrometers.
As per good coating practice stripe coats were applied at each stage of the coating cycle and each coat was applied in a contrasting colour.
As per our standard tank lining quality assurance the tank lining was tested for pin holing using a DC holiday spark tester, and where necessary repairs made.
To accelerate the cure of the lining to allow a rapid return to service, indirect oil fired heating was introduced.
The tank lining was complete in four days, working two shifts and coating application taking around the clock.