Dual winch nuclear fuel transfer system providing more reliable fuel

Abstract

A transfer system moves fuel assemblies along a track extending through a transfer tube within a containment wall in a nuclear power plant between the auxiliary building side and the containment building side. A car carries a basket for the assemblies. Two winches are located on the auxiliary building side above the water level existing over the track during refueling operations. The winches operate respective pairs of cables, driving the car in either direction. Four sheaves respectively direct the cables to the horizontal direction along the track. One pair of cables is secured to a yoke on the car to drive the car away from the containment building. Two horizontal sheaves are located near the containment end of the transfer tube. The other two cables extend horizontally along the track from the vertical sheaves to the horizontal sheaves, redirecting them to extend horizontally in the reverse direction. These return cables are secured to the yoke to drive the car toward the containment building. The winches are operated under the control of a programmable limit switch to move the car selectively between one end position in which the car is within the auxiliary building, and the other end position in which the car is principally within the containment building with at least the car yoke located over the track within the transfer tube and to the auxiliary building side of the horizontal sheaves.