Tank Linings
Merrydown had a problem with an existing lining in a large hopper which was used to receive the juice of freshly crushed apples, pears, etc. The tank was vertical cylindrical with a sharp conical floor. At some time during its history the tank had been relined but the company who carried out the work failed to completely remove the original lining prior to the application of the second lining and even the abrasion of the first lining was not carried out correctly as on the ceiling of the tank pieces of the new lining and falling off periodically into the product. The second lining was applied with a heavy fibreglass cloth and epoxy resin. The reason the tank failed was due to incorrect surface preparation by the second company and corrosion continued under the various layers of resin and fibreglass, the results of which meant that holes were formed in the walls of the tank in critical areas and cracks formed through the layers allowing product the get through the steel and contamination of the steel to get to the product. Another problem was that it made cleaning and sterilisation of the vessel very difficult.
All traces of the lining had to be removed back to bare steel and a new food grade lining applied. The removal of the several layers of the old lining was difficult and very time consuming but it had to be completely removed to ensure that we had a pure surface onto which to apply the new lining system.
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