Patent · US Expired

Fuel assemblies for nuclear reactors

US4655990A · kind A · utility

14Cited by
7References
2Claims
0Family size

Assignees

Inventor

Key dates

Filing dateMar 11, 1981
Grant dateApr 7, 1987
Priority date
Expiry dateMar 11, 2001

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E30/30
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

Improvements to guide tubes for the fuel assemblies of light water nuclear reactors, said assemblies being immersed in operation in the cooling water of the core of such a reactor, the guide tubes being of the type made from zircaloy and fixed at their two ends respectively to an upper end part and a lower end part made from stainless steel or Irconel and which incorporate devices for braking the fall of the control rods which they house during the rapid shutdown of the reactor, wherein the said braking devices are constituted by means for restricting the diameter of the guide tubes comprising for each guide tube a zircaloy inner sleeve spot welded to the said guide tube and whose internal diameter permits the passage, with a calibrated clearance, of the corresponding control rod, the sleeve being distributed over the lower portion of each guide tube and associated with orifices made in the actual guide tubes to produce the progressive hydraulic absorption of the end of the fall of the control rods. The invention also relates to a process for the disassembly of the guide tubes of a fuel assembly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.