Document Type and Number:
Japanese Patent JPH0482091
Kind Code:
U
Application Number:
JP12227390U
Publication Date:
July 16, 1992
Filing Date:
November 21, 1990
Export Citation:
International Classes:
E02D7/26; E02D13/10; E21B1/00; E21B1/26; (IPC1-7): E21B1/00; E02D7/26; E02D13/10
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