In the event of a conflict among the above listed standards or between the standards and other instructions listed in the specifications and drawing, it should be the Suppliers responsibility to notify the Buyer in writing for a resolution of the conflict prior to starting work.
Temperature and service conditions within the storage tank should be provided by Buyer.
Personnel qualification - Lining installation should be undertaken only by Personnel qualified by experience in installing the type of GRP lining proposed. Personnel should furnish details of below experience.
Proposal information - The following data should be submitted to Buyer for approval:
- All product specifications, MSDS sheets and ventilation requirements.
- Verification that the type of GRP lining proposed is suitable for the specified service conditions.
- Repair procedures for damaged areas.
- Reference panels (per Inspection and Testing section, Item 2 below) should be prepared by the Personnel.
Supplier should submit plans for Quality Assurance and Quality Control, the names of the coating inspectors, and their degree of training.
The resin system should be polyester, vinyl ester or epoxy suitable for the specified service conditions. The resin system of choice should be 100 percent volume solids (solvent-less) epoxy if it is suitable for the service conditions, since this system is inherently safer to apply than the polyester or vinyl ester systems. The glass content of GRP linings should be 20–30 percent by weight, excluding resin rich surface coatings. The coating materials used for tank lining applications are characterized by a variety of solvent and chemical hazards. Where suitable for the application conditions and service exposure conditions, high solids or solvent-less epoxies are to be preferred since they are inherently safer to apply than styrenated polyester or vinyl ester coatings.
Prime coating for the GRP should be an amine or polyamide cured epoxy.
Caulks for filling or smoothing of steel surfaces should be based on the resin used in the laminate.
Temperatures and service limitations for aggressive service should be determined by testing per ASTM C 581, unless satisfactory exposure experience at comparable conditions is clearly established.
Linings should be applied to all new aboveground storage tank bottoms where there has been a past history of bottom corrosion by the stored products.
The tank bottom lining should be extended to cover at least 18 in. (450 mm) of the first shell course.
Tank components such as equipment supports and flush draw-off nozzles, should be lined when specified.
Acceptable procedures for lining roof support column bearing areas are given in Figure 1 and Figure 2.
Figure 1 - Floating Roof Tank Roof-Support Legs
Figure 2 - Fixed Roof Tank Roof-Support Columns
6.0 Surface Preparation
All sharp burrs, edges, and weld spatter should be ground smooth.
Metal surfaces should be blast cleaned to a near-white metal finish per SSPC SP 10. The surface roughness should be per lining manufacturer recommendation.
Precautions should be taken to prevent contamination and damage during surface preparation and lining application.
Application of primer, GRP, and seal coats should be per below Table.