STEADY-REST MECHANISM OF SURFACE RUNNING INTEGRAL TRACK FOR NUCLEAR REACTOR PRESSURE VESSEL

摘要

PURPOSE:To absorb thermal expansion of a rail and vibration thereof due to earth quake by restricting motions other than vertical and radial ones in combination with a spring. CONSTITUTION:A 4-joint line ABCD is a main component. The joint A is fixed on a support 21F of a rail 3 while the joint C is fixed on a gamma shield 6 with a bracket 22. Spring hooks 23 and 24 are mounted on the joints B and D respectivly in such a manner as to be free to rotate and a spring 25 is interposed therebetween. As the rail 3 expands thermally, the point A is constrained in the direction X but free in the direction of Y+Z. Whenever the point A is moved to reduce the distance between A and B, it is returned by a reaction force of a spring 25. Extending the distance causes a sleeve 26 to hit against the spring hooks 23 and 24 while reducing it beyond a fixed range causes the spring hooks 23 and 24 to hit against stoppers 27 and 28. In this manner, any such an attempt is restricted.