Fuel assembly supporting structure

US3997394A · kind A · utility

Assignee

• Kraftwerk Union Aktiengesellschaft · DE

Inventors

• Friedrich-Wilhelm Aisch
• Hans-Peter Fuchs · Munich, DE
• Diethelm Knodler
• Alexander Steinke
• Josef Steven · Fairview Avenue, DE

Key dates

• Filing date: Mar 20, 1975
• Grant date: Dec 14, 1976
• Expiry date: Mar 20, 1995

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E30/30
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

For use in forming the core of a pressurized-water reactor, a fuel assembly supporting structure for holding a bundle of interspaced fuel rods, is formed by interspaced end pieces having holes in which the end portions of control rod guide tubes are inserted, fuel rod spacer grids being positioned by these guide tubes between the end pieces. The end pieces are fastened to the end portions of the guide tubes, to integrate the supporting structure, and in the case of at least one of the end pieces, this is done by means which releases that end piece from the guide tubes when the end pieces receive an abnormal thrust force directed towards each other and which would otherwise place the guide tubes under a compressive stress that would cause them to buckle. The spacer grids normally hold the fuel rods interspaced by distances determined by nuclear physics, and buckling of the control rod guide tubes can distort the fuel rod spacer grids with consequent dearrangement of the fuel rod interspacing. A sudden loss of pressure in a pressurized-water reactor pressure vessel, can result in the pressurized coolant in the vessel, discharging from the vessel at such high velocity as to result in …