Patent · US Expired

Self locking nut for fuel assembly tie rods

US5319691A · kind A · utility

5Cited by
10References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 12, 1993
Grant dateJun 7, 1994
Priority date
Expiry dateJul 12, 2013

Classification

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

Abstract

A method and an apparatus for locking the tie rods to block rotation relative to either the upper or lower tie plates utilizing the required fuel bundle channel. A conventional lock nut is provided for threading to the upper threaded end of the tie rods. This lock nut has attached extending wings, these wings when rotated interfering with a placed fuel bundle channel. In installation to the fuel bundle, and assuming that the tie rod has been fully threaded to the lower tie plate, the winged lock nut is rotated overlying the upper tie plate to cause full engagement of the upper tie plate to the tie rods. In such fastening, the winged lock nuts are rotated to an angle that provides no interference with the subsequently placed channel. Thereafter, and when the channel is placed, the channel interference with the rotational path of the wings of the lock nut and thus prevents relative rotation between the tie rod and winged lock nut. The fastening of the wings to the lock nut leaves portions of the hex surface of the lock nut exposed. Thus when bundle disassembly is required, only removal of the channel followed by conventional counter or unthreading rotation of the winged lock nut with…

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