Abstract: A pipe coupling assembly includes a first and a second pipe coupling member with the first coupling member including a cylindrical flange and a spherical convex seat portion, and the second coupling member including a cylindrical flange and a spherical concave seat portion. Each flange includes a first plurality of pivot notches. The coupling assembly further includes a first and a second cylindrical spring ring. Each spring ring includes a body having a first surface and an opposing second surface. The body includes a main bore and a plurality of bolt bores extending therethrough. A plurality of pivot bearings extend from the first surface with each pivot bearing configured to engage a pipe section flange notch. A plurality of bolt bore seats are located in the second surface and coaxially aligned with the bolt bores.

Abstract: A pipe coupling assembly includes a first and a second pipe coupling member with the first coupling member including a cylindrical flange and a spherical convex seat portion, and the second coupling member including a cylindrical flange and a spherical concave seat portion. Each flange includes a first plurality of pivot notches. The coupling assembly further includes a first and a second cylindrical spring ring. Each spring ring includes a body having a first surface and an opposing second surface. The body includes a main bore and a plurality of bolt bores extending therethrough. A plurality of pivot bearings extend from the first surface with each pivot bearing configured to engage a pipe section flange notch. A plurality of bolt bore seats are located in the second surface and coaxially aligned with the bolt bores.

Abstract: Coupling apparatus and methods for replacing a core spray line downcomer pipe coupled to a shroud T-box are described. In one embodiment, the coupling apparatus includes a seal ring, a mating flange, a housing, at least one coupling bolt, at least one spherical washer, and at least one lateral pin. The thermal expansion coefficient of the coupling bolt is lower than the thermal expansion coefficient of the seal ring, mating flange, and housing. After extending the downcomer pipe into the housing, the seal ring is inserted into the opposite end of the housing adjacent the downcomer pipe. The seal ring is then seated on the mating flange seat. The two seats allow the downcomer pipe to be rotational misaligned with the coupling apparatus. The coupling bolts extend through the mating flange and the housing to rigidly secure the downcomer pipe to the coupling apparatus.

Abstract: A method and an apparatus for repairing a core plate having a cracked support structure. The method entails the step of providing a vertical compression load path between the core plate and one or more control rod guide tubes. This is accomplished by installing a plurality of load-bearing wedges between the core plate and the step of each guide tube. Each load-bearing wedge is placed between the core plate and the guide tube machined step so that core plate pressure loads are reacted by the weight of the fuel rather than the core plate support structure. The load-bearing wedges can be installed without removing the guide tube or the fuel support casting.

Abstract: A method and an apparatus for repairing a core plate having a cracked support structure. The method entails the step of providing a vertical compression load path between the core plate and one or more control rod guide tubes. This is accomplished by installing a plurality of load-bearing elements between the core plate and the flanges of the guide tubes. Each load-bearing element is placed between the core plate and a guide tube flange so that core plate pressure loads are reacted by the weight of the fuel rather than the core plate support structure. The load-bearing element may take the form of a solid ring, a C-shaped spring collar or a hinged collar.