Protective Coatings – Tank Weld Repairs
THE PROBLEM
As part of the clients inspection regime the welds on their storage vessels require periodic non destructive testing to verify the integrity of the welds. As part of this process the coatings present must be removed by grit blasting and then reinstated following the completion of testing.
The existing coatings were removed by method of abrasive blasting, preparing the steel to SA2.5 as per the testers requirements. Once the testing works had been completed the steel was again blast cleaned to remove the testing fluid and prepare the steel to SA2.5.
Due to the size of the tanks and it not being possible or cost effective to control the humidity to prevent flash rusting we elected to use a surface tolerant protective coatings system from Chemco International. Two coats in contrasting colour of Chemco RL500PF surface tolerant epoxy primer finish were applied by brush and roller to a thickness of 300 microns.
Finally to prevent water ingress under the tank the interface between the steel and the concrete was sealed using a polyurethane jointing compound.