Epoxy Holding Primer Application.
Fiber glass lining,primer application should be applied as soon as approval for surface preparation is received.The primer DFT shall be within minimum 15µ and 50µ maximum.The primer application shall be done by airless spray method.
The spray gun nozzle shall be of correct size so that it provides the most suitable spray shape for the most effective and economical application of paint to the required DFT without any excessive over spray.
Ensure primer application is completed prior to any oxidation,flash rusting or discoloration occurs to the blasted surface.Particular attention shall be given to locations such as welds and difficult locations where the primer shall be patted with a brush to ensure the required coating thickness is obtained as a client requirements.
Caulking and Sealant Compound Application.
Above the primer coat all irregular location shall be filled with caulking (putty) compound to a level flush with the plate surface to obtain a smooth surface.Caulking shall be done as per client and manufacturer recommendations.
All the fillet welds of slip-on raisd face (SORF) flanged nozzles within the water level need to be sealed with caulking compound.A thin coat of 75µ-100µ with phenolic epoxy shall be applied with brush on top of the caulking and shall cover a maximum of 10mm on flange face.
The caulking shall be applied on all lap joints and weld joints such a way providing a gradual smooth transition.Caulking compound shall be a mixture of solvent free epoxy resin and treated aggregates,example Silica sand/Fumed Silica/Aerosil Powder.A fully cured caulking shall be rigid to provide strength and chemical resistance which shall be compatible with the lining system.
Large projection and thick plate edges shall be filled with caulking to smooth out the surface.Caulking shall be applied to shell to bottom plate weld junction to obtain a smooth surface so that fiber glass can be applied without bridging.The applied materials at this junction shall have a throat (Leg dimension) of 50mm as per client or manufacturer’s recommendations.