Document Type and Number:
Japanese Patent JPS62143797
Kind Code:
U
Application Number:
JP3076286U
Publication Date:
September 10, 1987
Filing Date:
March 04, 1986
Export Citation:
International Classes:
E21D9/087; E21B10/16; E21D9/08; (IPC1-7): E21D9/08
Domestic Patent References:
| JPS6023591A | 1985-02-06 |