Thomas E Dunlap

US Patent:

44204582, Dec 13, 1983

Filed:

Apr 29, 1981

Appl. No.:

6/258639

Inventors:

Thomas G. Dunlap - San Jose CA
William G. Jameson - San Jose CA
Carl R. Mefford - Los Gatos CA
Harold L. Nelson - San Jose CA
James E. Cearley - San Jose CA

Assignee:

General Electric Company - San Jose CA

International Classification:

G21C 332

US Classification:

376447

Abstract:

In a nuclear fuel assembly having a coolant conducting or water tube which also retains the spacers in axial position, the fuel rods experience greater axial growth with exposure than the water tube creating a risk that the water tube might become disengaged from the supporting tie plates. An arrangement for preventing such disengagement is described including lengthened end plug shanks for the water tube, a protective boss surrounding the lower end plug shank to protect it from flow induced vibration, a conical seat for the lower end plug and an arrangement for limiting upward movement of the water tube.

US Patent:

53848144, Jan 24, 1995

Filed:

Apr 12, 1993

Appl. No.:

8/044687

Inventors:

Bruce Matzner - San Jose CA
Eric B. Johansson - Wrightsville Beach NC
Richard A. Wolters - San Jose CA
Thomas G. Dunlap - San Jose CA
Robert B. Elkins - San Jose CA
Harold B. King - Wrightsville Beach NC
Paul W. Sick - Wilmington NC

Assignee:

General Electric Company - San Jose CA

International Classification:

G21C 104

US Classification:

376352

Abstract:

In a boiling water reactor fuel bundle, a three dimensional debris catching grid construction is placed within the flow volume defined by the lower tie plate assembly between the inlet nozzle and upper fuel rod supporting grid. A perforated plate is utilized having round holes as small consistent with the prevention of inadvertent closure due crudding and a hole pitch consistent with mechanical integrity requirements. The perforated plate is placed in a three dimensional construction such as a dome, cylinder, pyramid, inverted pyramid or corrugated construction spanning the flow volume of the lower tie plate assembly. As a consequence of this three dimensional grid construction, the total flow through area of the perforations in the metal plate does not introduce appreciable pressure drop in the lower tie plate assembly between the inlet nozzle and the rod supporting grid. Fluid movement at the debris restraining holes of the grid construction has a low flow velocity and a change in flow direction before passing through the holes to discourage debris from finding its way through the grid holes. Finally, it is possible to incorporate debris traps within the flow volume of the lower tie plate assembly that can cause trapping and subsequent removal of trapped debris upon fuel bundle replacement.

US Patent:

54835640, Jan 9, 1996

Filed:

Feb 15, 1994

Appl. No.:

8/196738

Inventors:

Bruce Matzner - San Jose CA
Eric B. Johansson - Wrightsville Beach NC
Richard A. Wolters - San Jose CA
Thomas G. Dunlap - San Jose CA
Robert B. Elkins - San Jose CA
Harold B. King - Wrightsville Beach NC
Paul W. Sick - Wilmington NC
Kevin L. Ledford - Wilmington NC

Assignee:

General Electric Company - Schenectady NY

International Classification:

G21C 104

US Classification:

376352

Abstract:

In a boiling water reactor fuel bundle, a three dimensional debris catching grid construction is placed within the flow volume defined by the lower tie plate assembly between the inlet nozzle and upper fuel rod supporting grid. A perforated plate is utilized having round holes as small consistent with the prevention of inadvertent closure due crudding and a hole pitch consistent with mechanical integrity requirements. The perforated plate is placed in a three dimensional construction such as a dome, cylinder, pyramid, inverted pyramid or corrugated construction spanning the flow volume of the lower tie plate assembly. As a consequence of this three dimensional grid construction, the total flow through area of the perforations in the metal plate does not introduce appreciable pressure drop in the lower tie plate assembly between the inlet nozzle and the rod supporting grid. Fluid movement at the debris restraining holes of the grid construction has a low flow velocity and a change in flow direction before passing through the holes to discourage debris from finding its way through the grid holes. Finally, it is possible to incorporate debris traps within the flow volume of the lower tie plate assembly that can cause trapping and subsequent removal of trapped debris upon fuel bundle replacement.

US Patent:

46751548, Jun 23, 1987

Filed:

Dec 20, 1985

Appl. No.:

6/811726

Inventors:

Harold L. Nelson - San Jose CA
Thomas G. Dunlap - San Jose CA
Eric B. Johansson - San Jose CA
Bruce Matzner - San Jose CA

Assignee:

General Electric Company - San Jose CA

International Classification:

G21C 332

US Classification:

376444

Abstract:

In a nuclear reactor fuel assembly, a relatively flexible mounting member for mounting a large coolant conducting tube to the lower tie plate whereby excessive side forces on the fuel rod spacers are avoided in the event of lateral displacement of the fuel assembly such as during a seismic event.

US Patent:

56469730, Jul 8, 1997

Filed:

Oct 12, 1995

Appl. No.:

8/542254

Inventors:

Richard A. Proebstle - San Jose CA
Christian D. Frederickson - Wilmington NC
Thomas G. Dunlap - Wilmington NC
Edward A. Croteau - Wilmington NC

Assignee:

General Electric Company - Schenectady NY

International Classification:

G21C 332

US Classification:

376434

Abstract:

A fuel bundle assembly for a nuclear reactor includes a lower tie plate; a transition piece underlying the lower tie plate; a plurality of fuel rods and at least one water rod seated on the lower tie plate and extending in substantially parallel relationship toward an upper end of the fuel bundle assembly, wherein a fuel bundle assembly lifting load is carried by load bearing members including certain of the fuel rods or by the at least one water rod; a plurality of spacers axially spaced along the at least one water rod and including means for laterally supporting each of the fuel rods; and a handle bar assembly at the upper end of the fuel bundle assembly connected to the load bearing members such that the plurality of non-load bearing fuel rods are supported only by the lower tie plate and the plurality of spacers.

US Patent:

56087683, Mar 4, 1997

Filed:

Jan 17, 1995

Appl. No.:

8/373373

Inventors:

Bruce Matzner - San Jose CA
Thomas G. Dunlap - Wilmington NC
Richard A. Proebstle - San Jose CA

Assignee:

General Electric Company - Schenectady NY

International Classification:

G21C 310

US Classification:

376451

Abstract:

In a fuel bundle assembly for a nuclear reactor wherein a plurality of fuel rods and tie rods extend between upper and lower tie plates and wherein some of the fuel rods are partial length fuel rods extending between the lower tie plate and a spacer located between the upper and lower tie plates, an improved end plug is provided for at least each of the partial length fuel rods, each end plug secured between a respective partial length fuel rod and the lower tie plate. The end plug includes an upper portion constructed of a first alloy material and including an exterior fuel rod receiving surface and a tapped hole in a lower end thereof, and a lower portion constructed of a second alloy material and including upper and lower threaded sections, the upper threaded section receivable within the tapped hole and the lower threaded section receivable within a tapped hole in the lower tie plate. The threaded end plug may be used with full length fuel rods as well as bundle tie rods. A related method of removing the fuel rod with the improved end plug from the lower tie plate is also disclosed.

US Patent:

51641550, Nov 17, 1992

Filed:

May 6, 1991

Appl. No.:

7/695663

Inventors:

Richard A. Wolters - San Jose CA
Anthony P. Reese - San Jose CA
Thomas G. Dunlap - San Jose CA

Assignee:

General Electric Company - San Jose CA

International Classification:

G21C 334

US Classification:

376441

Abstract:

A fuel bundle having spacers optimally deployed is disclosed wherein the distance between the spacers varies along the length of the fuel bundle. The fuel bundle has a dense fuel rod array (preferably in the range of 10. times. 10). It includes at least one part length rod extending from the lower tie plate toward but not to the upper tie plate, which part length rod terminates at a spacer and defines under the upper tie plate overlying the end of the spacer a vent volume for the preferential venting of vapor moderator (steam) from the fuel bundle. A vertical spatial distribution of the spacers is disclosed in which the bottom spacers in the single phase region of the fuel bundle are relatively closely vertically spaced and the upper spacers are relatively more distantly vertically spaced one from another. The design enables optimum resistance to flow induce vibration and rod bow, minimum interference of the spacers with pressure drop in the sensitive upper two phase region of the fuel bundle, and the required bracing of part length rods adjacent their ends.