APPARATUS AND METHOD FOR REINFORCING JET PUMP RISER

• US 20080205578A1
• Filed: 08/16/2007
• Published: 08/28/2008
• Est. Priority Date: 08/17/2006
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kinugasa, Kunihiko, Mori, Hajime, Hata, Haruhiko, Sudo, Kazuo, Kanazawa, Yasushi, Yasuda, Toshihiro, ABURA, Masakazu
• Granted Patent: US 8,718,222 B2
• Time in Patent Office: Days
• US Class Current: 376/372
• CPC Class Codes: G21C 15/25 using jet pumps
• CPC Class Codes: G21C 19/20 Arrangements for introducing objects into the pressure vessel; Arrangements for handling objects within the pressure vessel; Arrangements for removing objects from the pressure vessel
• CPC Class Codes: G21C 19/207 Assembling, maintenance or repair of reactor components G21C3/334 takes precedence
• CPC Class Codes: G21D 1/04 Pumping arrangements within the reactor pressure vessel G21C15/24; electrodynamic pumps H02K44/02
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors
• CPC Class Codes: Y10T 403/5761 Interrupted periphery, e.g., split or segmental, etc.

Abstract

An apparatus for reinforcing a jet pump riser includes: an elbow upper clamp for covering a riser elbow coupled to a thermal sleeve from an upper side thereof; an elbow lower clamping member for clamping the riser elbow from a lower side thereof; an elbow vertical portion clamping member for covering a vertical portion of the riser elbow; and an elbow horizontal portion clamping member for covering a horizontal portion of the riser elbow. These members are disposed in different orientations with respect to the elbow upper clamp so as to fix the thermal sleeve, the riser elbow and the riser pipe.

Claims

1. An apparatus for reinforcing a jet pump riser disposed in a reactor pressure vessel of a boiling water reactor, comprising:

an elbow upper clamp for covering a riser elbow of a jet pump riser and coupled to a thermal sleeve from an upper side thereof;

an elbow lower clamping member for clamping the riser elbow from a lower side thereof;

an elbow vertical portion clamping member for covering a vertical portion of the riser elbow; and

an elbow horizontal portion clamping member for covering a horizontal portion of the riser elbow,

wherein the elbow lower clamping member, the elbow vertical portion clamping member and the elbow horizontal portion clamping member are disposed in different orientations with respect to the elbow upper clamp so as to fix the thermal sleeve, the riser elbow and the riser pipe.

2. The apparatus for reinforcing a jet pump riser according to claim 1, wherein the elbow lower clamping member, the elbow vertical portion clamping member and the elbow horizontal portion clamping member are formed as a foldable integral structure which includes a plurality of clamping members.

3. The apparatus for reinforcing a jet pump riser according to claim 1, wherein the elbow lower clamping member, the elbow vertical portion clamping member and the elbow horizontal portion clamping member are formed as a plurality of U-shaped members separated from each other.

4. The apparatus for reinforcing a jet pump riser according to claim 1, wherein the elbow lower clamping member, the elbow vertical portion clamping member and the elbow horizontal portion clamping member are formed as a plurality of ring-shaped members separated from each other.

5. The apparatus for reinforcing a jet pump riser according to claim 1, wherein at least one of the elbow upper clamp, the elbow lower clamping member, the elbow vertical portion clamping member and the elbow horizontal portion clamping member has a movement restricting structure by fitting between recessed and protruded portions with respect to an outer peripheral surface of the riser elbow.

6. A method for reinforcing a jet pump riser, comprising the steps of:

disposing an apparatus for reinforcing the jet pump riser into a reactor pressure vessel of a boiling water reactor, the apparatus including;

an elbow upper clamp for covering the riser elbow of a jet pump riser coupled to the thermal sleeve from an upper side thereof;

an elbow lower clamping member for clamping the riser elbow from a lower side thereof;

an elbow vertical portion clamping member for covering a vertical portion of the riser elbow; and

an elbow horizontal portion clamping member for covering a horizontal portion of the riser elbow, in a state that the elbow lower clamping member, the elbow vertical portion clamping member, and the elbow horizontal portion clamping member are disposed in different orientations with respect to the elbow upper clamp; and

fixing a thermal sleeve, a riser elbow and a riser pipe.