Frictionally loaded top end supports for cantilever-mounted rod guides

Abstract

A pressurized water reactor of an advanced design comprises, in vertically spaced relationship, a lower barrel assembly having lower and upper core plates, an inner barrel assembly and an axially removable calandria assembly having a lower calandria plate. A plurality of rod guides are cantilever-mounted in parallel axial relationship within the inner barrel assembly by rigidly mounting the lower ends thereof to the upper core plate. Axially extending sleeves affixed to the upper ends of the rod guides and telescopingly receive therein generally cylindrical supports which are affixed to and depend downwardly from the lower calandria plate and define alignment axes for the respectively associated rod guides. Axially extending leaf springs in each sleeve are normally biased radially inwardly and, in the assembled relationship of the calandria and inner barrel assemblies, resiliently and frictionally engage the respective cylindrical supports to maintain alignment and react both lateral and axial loads. Load pick-up surfaces of non-yielding sleeve portions react excessive loads directly into the lower calandria plate. Mating top end supports for RCC and WDRC rod guides permit dense packing of same, while internal openings of the top end supports permit telescoping movement of the corresponding rod clusters therethrough to permit ease of assembly and disassembly operations.