Patent · US Expired

Grid spacer and method of making same

US4756878A · kind A · utility

22Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 1, 1986
Grant dateJul 12, 1988
Priority date
Expiry dateDec 1, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/531
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A marked reduction in the pressure drop of cooling liquid through a grid spacer of a nuclear fuel assembly is attained by convexly contouring the upstream (usually the lower) edges of the grid members. Preferably, they are made streamlined or semicylindrical. This can be done by first beveling and then etching them, by directing a stream of mixture of abrasive and an organic polymer against them, or by traversing an electron or laser beam along them at a power and velocity such as to cause local melting. A lesser improvement is secured by beveling alone. A still further improvement can be obtained by also tapering the downstream (usually upper) edges.

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