General Electric Company

Hsueh-Wen Na Pao

Frank Ortega

Fred Charles Nopwaskey

Gary Allen Boortz

Johnny T Ma

Jack Toshio Matsumoto

Henry Peter Offer

David L Faulstich

Dane T Snyder

David Bryan Drendel

David Wesley Sandusky

Ahdee Quan Chan

Kenneth R Izzo

John Edward Maslakowski

Martin Sullivan Laurent

Joel C Swanson

Peter F Kachel

A surface conditioning scheduling process is used to mitigate susceptibility to crack initiation or crack growth in a boiling water nuclear reactor using a plurality of working crews. A plurality of working zones are defined in an annulus region of a reactor vessel flange, and a plurality working zones are defined in a core region of the reactor vessel. One of the working crews is positioned in each of the annulus region working zones, and one of the working crews is positioned in each of the core region working zones. The working crews perform surface conditioning in areas of the reactor vessel accessible from their respective working zones such that the surface conditioning process can be completed in no more than thirty days.

Renew process implementation for reactor bottom head

A lower housing having a lower chamber and a welding opening is fixed about an underwater weld site. The lower housing includes an upper opening, the lower housing being filled with water upon installation. A transport housing containing a welding unit in a dry state is lowered such that a bottom opening, closed by a closure element, registers with an upper opening of the lower chamber. Upon clamping the housings together, the lower chamber is at least partially evacuated. The closure element is then moved to an open position and the welding unit is lowered into the evacuated lower chamber to weld a patch to the vessel wall to overlay the damaged area.

Apparatus and methods for underwater welding

An ultra high pressure abrasive waterjet cutting apparatus for cutting nuclear reactor structural components is described. The cutting apparatus includes an ultra high pressure abrasive waterjet (UHP) cutting nozzle, movably coupled to a single axis manipulator, and a collection hood. The manipulator and the collection hood are coupled to a support frame and are configured to be positioned inside adjacent openings of a nuclear reactor top guide or core plate so that the cutting nozzle is in alignment with the collection hood. The manipulator includes a linear frame, a nozzle support plate movably coupled to the linear frame, and a motor operatively coupled to the nozzle support plate. The collection hood includes an elongate collection chamber having an elongate opening located so that the opening is in alignment with the cutting nozzle. The collection hood also includes at least one positioning cylinder coupled to the collection chamber and to the support frame which positions the collection chamber opening adjacent a top guide or core plate beam. The collection hood further includes an outlet port configured to be connected to a water filtration system.

Ultra high pressure abrasive waterjet cutting apparatus

A core spray sparger for use in a nuclear reactor pressure vessel. The core spray sparger includes a plurality of core spray lines, a coupling apparatus, a bracket assembly, and an end clamp assembly. The core spray line includes a core spray line end cap.

Core spray system attachment assemblies

An ultra high pressure abrasive waterjet cutting apparatus for underwater cutting of structural components of a nuclear reactor is described. The cutting apparatus includes a multi-axis manipulator, an ultra high pressure abrasive waterjet (UHP) cutting nozzle coupled to the manipulator, a collection stand assembly, a collection hood movably coupled to the collection stand assembly, and a turntable having a non-movable center portion. The multi-axis manipulator is configured to mount on the non-movable center portion of the turntable or on the floor of the pool of water in which the structural component is positioned for cutting. The collection stand assembly is configured to mount on at least one of the floor and the wall of the pool of water. The cutting nozzle and collection hood are positioned on opposite sides of the structural component to be cut.

Floor mounted ultra high pressure abrasive cutting apparatus

The weld reinforcement includes a generally dogbone-shaped pocket having laterally enlarged end portions and a reduced intermediate portion spanning a weld seam. A complementary-shaped reinforcing element is received in the pocket. The pocket includes a projection which is received in an opening in the overlying reinforcing element. A wedge-type clamp retainer is received about the projection within the opening to secure the element within the pocket.

Weld reinforcement

A process and a system for detecting defective nuclear fuel assemblies in situ. The system includes two basic subsystems. The first subsystem is a sample collection system consisting of a hood placed over the fuel. A technique whereby a vacuum is drawn across a submerged nozzle of a degas tank is used to draw up the sample of fluid out of a fuel assembly. The second subsystem determines the amount of Kr-85 radioisotope contained in the fluid sample. This information is used to determine whether the fuel assembly contains a defective, i.e., leaking, fuel rod. The measurement values for Kr-85 in the fluid sample extracted from the fuel assembly are compared to the measurement values for Kr-85 in fluid samples taken from the reactor pool prior to fuel assembly testing and fluid samples taken from non-leaking control cells, the latter values representing the background to which the subject fuel assembly is compared. Based on this comparison, a determination is made concerning whether the subject fuel assembly is defective.

Growing community of inventors

Saratoga, CA, United States of America

Hsueh-Wen Na Pao