Collar clamp assembly for repairing core spray piping

Abstract

A collar clamp assembly is disclosed for repairing and providing a temporary seal around leaking pipe coupling areas of an internal core spray system of a nuclear reactor. The clamp assembly includes first and second housings having respective first and second ends and a pair of longitudinal edges between the ends. The housings have a tongue and groove mating configuration along the longitudinal edges to seal and accommodate variations in the outside diameter of the core spray piping. A plurality of threaded fasteners are used to secure the first and second housings together to form a closed conduit shaped to receive a length of the core spray piping, including the leaking pipe coupling. First and second seals are located at first and second longitudinally spaced positions, respectively, on each of the first and second housings and extend around the closed conduit. The seals are oriented to seal the housings against the outer circumferential surfaces of the core spray piping on either side of the leaking pipe coupling. A grip structure configured to engage and grip an outer circumferential surface of the core spray piping is provided to prevent the pipe coupling from pulling apart in a longitudinal direction. Variations in the seals, the grip structure, and the housings are disclosed.