Abstract: An improved method of replacing at least a portion of a shroud apparatus of a BWR includes forming a cut in the shroud and removing at least a portion of the shroud apparatus that is adjacent the cut from a remaining portion of the shroud apparatus. The method also includes positioning a replacement shroud system adjacent the remaining portion of the original shroud apparatus and connecting a plurality of removable fastening devices between the new replacement shroud system and the remaining portion of the original shroud apparatus. The replacement shroud system thus can, in the future, be readily replaced by detaching the removable fastening devices, removing the replacement shroud system, and installing a new replacement shroud system with less effort than was required in cutting through the original shroud and replacing it with the replacement shroud system. An improved replacement shroud system is also disclosed.

Abstract: An improved method of replacing at least a portion of a shroud apparatus of a BWR includes forming a cut in the shroud and removing at least a portion of the shroud apparatus that is adjacent the cut from a remaining portion of the shroud apparatus. The method also includes positioning a replacement shroud system adjacent the remaining portion of the original shroud apparatus and connecting a plurality of removable fastening devices between the new replacement shroud system and the remaining portion of the original shroud apparatus. The replacement shroud system thus can, in the future, be readily replaced by detaching the removable fastening devices, removing the replacement shroud system, and installing a new replacement shroud system with less effort than was required in cutting through the original shroud and replacing it with the replacement shroud system. An improved replacement shroud system is also disclosed.

Abstract: The invention relates to a compression joint for reinforcement and support over bent tubular components. According to the invention, a first sleeve (5) is applied around the bent tubular component, the inner surface (10) of the first sleeve being formed to fit closely around the tube at the point of reinforcement. This sleeve (5) is divided into at least two parts along axial sections and has an outer, substantially rotationally symmetrical surface (11). Around this sleeve (5), a second sleeve (9) with an inner rotationally symmetrical surface is arranged. The outer surface of this second sleeve (9) is adapted to receive a winding (14, 15) comprising several layers of strip or wire of memory metal.

Abstract: A replacement valve seat device for insertion in a recess of a valve where a valve seat has been removed includes a first ring which provides a valve seat and a cooperating second ring of memory metal which is expandable upon being heated above its transistion temperature to fixedly position the first ring in position within the recess.

Abstract: A method for sealing a leak between a control rod drive (CRD) stub tube (3) arranged in a reactor wall (2) and a tubular CRD housing (1) extending through the CRD stub tube (3) and the vessel wall (2). According to the invention, this sealing is obtained by deforming a suitably shaped element of memory metal below the transition temperature of the memory metal in such a way that it can be inserted, in the form of a sleeve (5) or a ring, into or around the CRD housing (1) where said housing passes through the vessel wall (2), or alternatively replace part of the CRD housing (1) at the passage through the vessel wall (2). Then when the memory metal is heated to above the transition temperature, it strives to resume its original shape which shall then have been such that the desired seal is obtained.

Abstract: The invention relates to a sealing joint for pipes (3) or pipe sockets (2) in, for example, a nuclear reactor. The joint comprises at least two sealing bodies (4, 5) contacting each other in a contact surface (8) and provided with through holes (6, 7). The holes (6, 7) are delimited by envelope surfaces (9, 10) and form a tubular channel (11) through the sealing bodies (4, 5) and the contact surface (8). The sealing bodies (4, 5) are displaceable in relation to each other along the contact surface (8). Around the channel (11) a sealing member (12) is arranged between the sealing bodies (4, 5). Each one of the sealing bodies (4, 5) is divided into at least two discs (4a, 4b; 5a, 5b, respectively) in a plane intersecting the associated envelope surface (9, 10) along a closed curve. Between the discs belonging to a sealing body (4, 5), a slot (13 ) has been provided which is delimited by the associated envelope surface (9, 10). A flexible sealing ring (13a) is inserted into the slot (13).

Abstract: The invention relates to a sealing sleeve for sealing a leak in, for example, a pipe, a pipe socket or the like in a nuclear reactor. The sleeve comprises a bellows-like mid-portion (1) with annular ends, at least these or part of these (2) being made of a memory metal with a suitable transition temperature. At a temperature above the transition temperature, that part of these annular ends which consists of memory metal has been given an inner diameter suitable for achieving sealing around the relevant pipe section on each side of the leak. The mentioned part of the ends has thereafter, at a temperature below the transition temperature, been deformed into a diameter which permits the sleeve to be freely fitted onto the pipe. In fitted position, the sleeve is then heated to above the transition temperature, the memory metal then striving to recover its previous shape and shrinks the sleeve so as to obtain sealing.