Abstract: A seal assembly for sealing a space between an annular flange on a nuclear reactor vessel and a surrounding ledge of a refueling canal to provide a temporary water barrier during refueling operations. The seal assembly includes an annular closure plate having an outer portion secured to the surrounding ledge and an inner portion supporting a first sealing surface. A second sealing surface opposing the first sealing surface is formed on or secured to the annular flange of the reactor vessel. An annular space between the first and second sealing surfaces provides a ventilation path from the reactor cavity during normal plant operation. The annular space is sealed by an inflatable seal during refueling operations to provide a water barrier between the refueling canal and the reactor vessel. The inflatable seal is secured to and supported by an annular support structure that straddles the annular space.

Abstract: An augmented cooling system for a CEDM in a nuclear reactor includes self actuated louvers or flap valve louvers which allow hot air from the head lift rig to vent and cooler ambient air to enter the rig in the event that pressure is lost for the forced cooled air which normally cools the CEDM.

Abstract: A tank (18) forms a chamber having an upper and lower region. The tank (18) is in even elevation with a horizontal pipe (12) having a top region and a bottom region. An upper connecting pipe (14) fluidly connects the top region of the pipe (12) to the upper region of tank (18). A lower connecting pipe (16) fluidly connects the bottom region of pipe (12) to the lower region of the tank (18). Heat junction thermocouples (22) generate a signal indicative of water in the pipe (12). The signal is transmitted to a remote location by line (24).

Abstract: A head equipment support structure system (HESS) (10) particularly adapted to be cooperatively associated with a nuclear reactor vessel (12) for purposes of effecting a separation of the electrical cables (30) that are utilized in the head area of such a vessel (12), as well as for purposes of providing support for these cables (30). The subject HESS (10) which is in the form of an integral structure that is removably supported relative to the vessel (12) combines the features of cable support structure, missile shield, and cooling ductwork support structure. The HESS (10) embodies horizontally disposed multiple decks (14) to which the cables (30) are vertically routed from the reactor vessel head. The decks (14), which are located in vertically spaced relation directly above the reactor vessel head, support and separate the cables (30).