发明名称 |
Inner Bit Disposed within an Outer Bit |
摘要 |
In one aspect of the present invention, a drill bit assembly for downhole drilling comprises an outer bit comprising a central axis and an outer cutting area and an inner bit disposed within the outer bit and comprising an inner cutting area. The outer bit comprises a first plurality of cutting elements and the inner bit comprises a second plurality of cutting elements wherein an average distance of each cutting element in the first plurality to the central axis forms a first moment arm and an average distance of each cutting element in the second plurality to the central axis forms a second moment arm. A ratio of the inner cutting area to the outer cutting area is substantially equal to a ratio of the outer moment arm to the inner moment arm.
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申请公布号 |
US2011240366(A1) |
申请公布日期 |
2011.10.06 |
申请号 |
US20100894371 |
申请日期 |
2010.09.30 |
申请人 |
HALL DAVID R;LEANY FRANCIS;WEBB CASEY;SKEEM MARCUS |
发明人 |
HALL DAVID R.;LEANY FRANCIS;WEBB CASEY;SKEEM MARCUS |
分类号 |
E21B7/00;E21B10/36 |
主分类号 |
E21B7/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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