Abstract: In a nozzle dam assembly wherein a circular dam faces into a nozzle adjacent its opening and a support frame abuts the backside of the dam and is removably affixed across a ring encircling the opening, apparatus for selectively locating the dam at its optimum sealing position within the nozzle notwithstanding the particular longitudinal profile of the nozzle or eccentricity of the ring-relative to the nozzle opening comprising apparatus for adjusting the dam relative to the frame along the nozzle axis and also vertically and horizontally perpendicular to the nozzle axis.

Abstract: An improvement in a reactor cavity pool seal which includes a seal plate between the reactor and the cavity wall and an inflatable annular seal, wherein the inflatable seal operates between a seal ring and bearing plate which are elements in addition to the seal plate and cavity wall, thereby eliminating problems of eccentricity and clearance.

Abstract: A cable-driven arm-reciprocating system particularly useful for transferring nuclear fuel bundles from a nuclear reactor pool to a spent fuel storage pool, wherein an arm-retracting cable extends from a winch drum around fixed and movable-axis sheaves to a retracting anchor device and an arm-extending cable extends from the same winch drum also around fixed and movable-axis sheaves to an extending anchor device, each anchor device including spring means for maintaining and allowing for variations in cable tension.

Abstract: A method, and an apparatus for carrying out the method, for displacing a weld scanner in and out of a horizontal reactor vessel nozzle submerged in a water pool characterized by buoyancy chambers into which water and air may be introduced by remote control to move the scanner and an associated telescopic boom, column and spider into position relative to the reactor vessel.