Abstract: A prefabricated in-core nuclear plant instrumentation chase concrete form is provided that has integral embedment plates at the locations where the in-core instrumentation guide thimble supports contact the walls of the chase. Structural steel shapes are located on the outside of the prefabricated chase at the embedment locations to transfer loads on axially-spaced, transverse, thimble support plates that route and support guide thimbles through which the in-core instrumentation pass, into the surrounding concrete structure. The guide thimble supports are installed in the pre-fabricated chase form at the factory and serve to strengthen the structure during shipping and handling as well as resist the loads applied by the wet concrete poured around the prefabricated chase during installation at a nuclear plant site.

Abstract: A nuclear steam supply containment system employing prefabricated component supports that are surrounded by steel concrete forms and anchored to the floor liner of a nuclear containment. The prefabricated component supports extend through the concrete forms and a reinforce concrete slab cap to a support elevation for the component. A second inner steel concrete form can be employed to form an annular concrete channel through which the supports extend. The center of the inner form can be filled with a sand-like substance, radiation absorber material or concrete grout.

Abstract: A removable rail assembly for use with a spent fuel handling machine, including a support rail, a rail guide carried by the support rail, a rail joint connector supported by the rail guide for coupling the rail guide to adjacent rails, and at least one jacking screw supported by the support rail for lifting the support rail assembly. Another embodiment of the invention includes a second jacking screw received in the top surface of the rail guide. The joint connector is tongue and groove joint with a tapered parting line that permits a tight fit between the removable rail and adjacent fixed rails. During removal of the removable rail, the jacking screw distributes a uniform lifting force along the length of the rail, loosening the joint connector. Once the joint connector is loosened, the rail is coupled to a lifting crane and transported to a storage area.

Abstract: A measurement chamber (18) having an upper and a lower region is at substantially the same elevation as a horizontal pipe (12) having a top region and a bottom region. An equalization line (14) fluidly connects the top region of the pipe (12) to the upper region of measurement chamber (18). A sample line (16) fluidly connects the bottom region of pipe (12) to the lower region of the measurement chamber (18). Heat junction thermocouples (22) generate a signal indicative of the level of fluid in the measurement chamber (12) which is equal to the level of fluid in the pipe (12). The signal is transmitted to a remote location by line (24).

Abstract: In order to reduce the number of lifts which are required to remove the various equipment normally disposed above the reactor pressure vessel and to make way for refuelling or regular maintenance, the control rod element drive mechanisms are completely enclosed within a cylindrical enclosure which is attached to the head of the pressure vessel. The top of the cylindrical enclosure is closed with a cap-like member which acts as both a missile shield and a head area cable tray. The missile shield, the cylindrical enclosure, the control rod drive mechanisms and the pressure vessel head, are connected to form an integral unit which can be removed in a single lift. Cable trays are pivotally supported on a wall of a building to establish a bridge between the building and the head area cable array and to establish a connection with the control element drive mechanism cables. During lifting, the control element drive mechanism cables are disconnected and the pivotal bridge trays are swung out of the way.