Published November 10, 1995 | Version v1
Patent

Shielding device for control rod in nuclear reactor

Description

The device of the present invention shields radiation emitted from control rods to greatly reduce an operator's radiation exposure even if reactor water level is lowered and the upper portion of the control rod is exposed upon inspection of a BWR type reactor. Namely, a shield assembly has a structure comprising a set of four columnar shields in a two-row and two-column arrangement, which can be inserted into a control rod guide tube. Upon conducting inspection, the control rod is lowered into the control rod guide tube, and in this state, the columnar shields of the shield assembly are inserted to the control rod in the control rod guide tube. With such procedures, the upper portion of the control rod protruded from the control rod guide tube is covered with the shield assembly. As a result, radiation leaked from the control rod is shielded. Accordingly, irradiation in the reactor due to leaked radiation can be prevented thereby enabling to reduce an operator's radiation exposure. (I.S.)

Availability note (English)

Available from JAPIO. Also available from EPO.

Additional details

Publishing Information

Imprint Pagination
5 p.
IPC:
Int. Cl. G21C7/10; G21C7/14.
IPC
Int. Cl. G21C7/10; G21C7/14.
Patent number
JP patent document 7-294677/A/

INIS

Country of Publication
Japan
Country of Input or Organization
Japan
INIS RN
27045215
Subject category
S21: SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS;
Resource subtype / Literary indicator
Non-conventional Literature
Descriptors DEI
BWR TYPE REACTORS; CONTROL ELEMENTS; GUIDE TUBES; LEAKS; RADIATION DOSES; RADIATION PROTECTION; REACTOR MAINTENANCE; SHIELDING; SHIELDING MATERIALS
Descriptors DEC
ENRICHED URANIUM REACTORS; MAINTENANCE; MATERIALS; POWER REACTORS; REACTOR COMPONENTS; REACTORS; THERMAL REACTORS; TUBES; WATER COOLED REACTORS; WATER MODERATED REACTORS

Optional Information

Secondary number(s)
JP patent application 6-89762.