Dong Hoon Chung

US Patent:

43137946, Feb 2, 1982

Filed:

Feb 15, 1979

Appl. No.:

6/012275

Inventors:

Dong K. Chung - Chatsworth CA

Assignee:

Rockwell International Corporation - El Segundo CA

International Classification:

G21C 706

US Classification:

376352

Abstract:

A self-actuating, self-locking flow cutoff valve particularly suited for use in a nuclear reactor of the type which utilizes a plurality of fluid support neutron absorber elements to provide for the safe shutdown of the reactor. The valve comprises a substantially vertical elongated housing and an aperture plate located in the housing for the flow of fluid therethrough, a substantially vertical elongated nozzle member located in the housing and affixed to the housing with an opening in the bottom for receiving fluid and apertures adjacent a top end for discharging fluid. The nozzle further includes two sealing means, one located above and the other below the apertures. Also located in the housing and having walls surrounding the nozzle is a flow cutoff sleeve having a fluid opening adjacent an upper end of the sleeve, the sleeve being moveable between an upper open position wherein the nozzle apertures are substantially unobstructed and a closed position wherein the sleeve and nozzle sealing surfaces are mated such that the flow of fluid through the apertures is obstructed. It is a particular feature of the present invention that the valve further includes a means for utilizing any increase in fluid pressure to maintain the cutoff sleeve in a closed position. It is another feature of the invention that there is provided a means for automatically closing the valve whenever the flow of fluid drops below a predetermined level.

US Patent:

48287601, May 9, 1989

Filed:

Feb 8, 1988

Appl. No.:

7/153548

Inventors:

Dong K. Chung - Chatsworth CA
Charles E. Jones - Northridge CA

Assignee:

Rockwell International Corporation - El Segundo CA

International Classification:

G21C 1948
B08B 902

US Classification:

252627

Abstract:

A method of cleaning a fuel assembly contaminated with a radioactive alkali metal in which the fuel assembly is subjected to heating with an inert gas followed by being placed under vacuum and finally cooled with an inert gas; the latter two steps being performed in repetitive cycles.