Original document(13 pages) Authorized document(13 pages) 中文版
    A rotary-percussion device for directional drilling in rock comprises a substantially cylindrical, rotatable body portion (15) housing a percussion hammer, and a frustroconical head (2) eccentrically mounted on the front of the body portion. The minimum diameter face (3) of the head is adjacent to the body portion. The axis (6) of the head is parallel to but offset from the axis (5) of the body. The front face (4) of the head is chisel-shaped and comprises at least one oblique plane (11) sloping forwardly in the same direction as the offset of the head axis relative to the body axis.
Application Number
98811838 Application Date
Title 名称 Directional drilling tool
Publication Number
1280646 Publication Date
Approval Pub. Date 2003.08.13 Granted Pub. Date 2003.08.13
International Classification 分类号 E21B6/00;E21B7/08;E21B7/28;E21B10/46;E21B36/00
Applicant(s) Name
Address 地址
Inventor(s) Name 发明人 G. Esposito
Attorney & Agent 代理人 zheng jianhui

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