Rotating rolling gantry for nuclear reactor chambers - with movable supports designed to facilitate crane re-centering

摘要

Rotating rolling gantry consists of supporting beams joined together by cross beams to form a rigid rectangular framework supported at each corner on a gyratory beam movable along a circular track by means of movable supports. Each movable support is a spherical bearing consisting of a ball point and a undirectional slide plate of low coefft. of friction. Each gyratory beam consists of a box carried by two axles provided with wheels, one axle being mounted on a fixed bearing attached to the box, the other being mobile w.r.t. the box and mounted on the box so as to be able to oscillation a vertical plane about a longitudinal shaft perpendicular to the vertical plane passing through the mobile axle. The gantry is used inside a nuclear reactor chamber and carries a crane equipped with redundant winches. Difficulties of prior art in recentring the crane after decending are overcome.