Patent · US Expired

Check valve test method for control rod drive

US4863673A · kind A · utility

4Cited by
4References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 26, 1988
Grant dateSep 5, 1989
Priority date
Expiry dateAug 26, 2008

Classification

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

Abstract

In a hydraulic system of a control rod drive for insertion of control rods, a test apparatus and test process is disclosed for determining the integrity of the hydraulic system check valve for preventing inadvertent control rod ejection responsive to the reactor pressure. The check valve is located between a hydraulic valve for causing rod insertion and the hydraulic cylinder. In this interval downstream of the check valve, alteration is made to the hydraulic path by the installation of a conduit with a quick disconnect connected through an isolation valve. Test apparatus for temporary connection at the disconnect is disclosed consisting of a small positive displacement piston and cylinder. The small positive displacement piston and cylinder connects to the quick disconnect through a complementary quick disconnect fitting and a rapidly opening toggle valve. Provision is made for timing the excursion of piston in the piston and cylinder preferably by end of stroke microswitches. A process for the testing of the integrity of the check valve is disclosed in which quick opening valve is opened with resultant backflow from the hydraulic system through the check valve into the volume def…

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