Jet pump measurement pipe repair method

Patent metadata

Field	Value
Publication number	US-9312036-B2
Application number	US-201113315887-A
Country	US
Kind code	B2
Filing date	Dec 9, 2011
Priority date	Dec 10, 2010
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

In a jet pump measurement pipe repair method according to the present embodiment, a breakage part of a measurement pipe horizontally fixed to a lower part of a jet pump provided in reactor water in a reactor pressure vessel is repaired. The method has: a step of cutting and removing the measurement pipe including the breakage part; a step of retaining a connection pipe for connecting the remaining measurement pipe on the jet pump by means of a clamp; and a step of connecting ends of the remaining measurement pipe by means of the connection pipe.

First claim

What is claimed is:

1. A jet pump measurement pipe repair method for repairing a breakage part of a measurement pipe which is horizontally fixed to a lower part of a jet pump provided in reactor water in a reactor pressure vessel, the method comprising:
cutting the measurement pipe including the breakage part;
cutting a support member supporting the measurement pipe to a diffuser of the jet pump;
removing part of the measurement pipe and part of the support member;
fixing, by a clamp, a spool piece having a tubular shape directly to part of the support member remaining after the removing, both ends of the spool piece being connected to connection pipes, for supplementing the measurement pipe having been cut and removed;
deforming the spool piece having the tubular shape to match a shape of the breakage part; and
connecting ends of the remaining measurement pipe to the connection pipes.

2. The jet pump measurement pipe repair method according to claim 1 , wherein
the connection pipe used in the connecting is made of shape-memory alloy.

3. The jet pump measurement pipe repair method according to claim 1 , wherein
the connection pipe used in the connecting is a biting joint including a joint body, union nuts, and sleeves.

4. The jet pump measurement pipe repair method according to claim 1 , wherein
in the connecting, the ends of the remaining measurement pipe and the connection pipes are connected by welding.

Assignees

• Minato Yuki
• Yasuda Toshihiro
• Kinugasa Kunihiko
• Mori Hajime
• Yamamoto Satoshi
• Suzuki Jun
• Mitsuhashi Tadahiro
• Toshiba Kk

Inventors

• Minato Yuki
• Yasuda Toshihiro
• Kinugasa Kunihiko
• Mori Hajime
• Yamamoto Satoshi
• Suzuki Jun
• Mitsuhashi Tadahiro

Classifications

• Y10T29/49735

  Mechanically attaching preform with separate fastener · CPC title

• G21C19/14

  characterised by their adaptation for use with horizontal channels in the reactor core · CPC title

• F04F5/54

  Installations characterised by use of jet pumps, e.g. combinations of two or more jet pumps of different type · CPC title

• G21C15/25 Primary

  using jet pumps · CPC title

• G21C17/10

  Structural combination of fuel element, control rod, reactor core, or moderator structure with sensitive instruments, e.g. for measuring radioactivity, strain · CPC title