A 50 foot (15.2 m) diameter by 36 foot (11 m) straight shell field erected fiberglass reinforced plastic
(FRP) tank containing 37% hydrochloric acid developed a leak at its third module seam, approximately
18 feet (5.5 m) off the ground. The tank is made up of four filament wound horizontal sections or
modules that are 50 feet (15.2 m) in diameter by 8 feet (2.4 m) high. The leak occurred in a vertical
crack at the joint between the second and third modules. This paper discusses interesting findings,
fabrication issues, and describes the repair techniques used to successfully return the vessel to service.
In light of the large field erected vessels being fabricated for the United States power industry today,
this paper is particularly applicable to repairs these vessels may require in the future.
Key Words: FRP, fiberglass, fiberglass repairs, hydrochloric acid, resins, resin laminates, test patch,
filament wound, modules, field-erected.