Document Type and Number:
Japanese Patent JPH025484
Kind Code:
U
More Like This:
Application Number:
JP8051988U
Publication Date:
January 16, 1990
Filing Date:
June 20, 1988
Export Citation:
International Classes:
E21B3/02; (IPC1-7): E21B3/02
Domestic Patent References:
| JP63076091B | ||||
| JP62169089B |
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