| 摘要 |
A coring member useful in wellbore excavating operations comprising at least one segment disposed onto the end of a shaft, where a channel is formed between each at least one segment. The at least one segment has an impeller like arrangement that on rotation produces a pressure differential across the face of the coring member. The impeller like arrangement comprises an obliquely attached vane on one side of the face, and an obliquely attached rib on the other side. Rotation of the coring member within a fluid produces a localized high-pressure zone adjacent the face of each rib and a corresponding low-pressure zone adjacent the face of each vane. Each channel provides fluid communication between a vane and a rib, where the vane and the rib are located on different but adjacent segments. The pressure differential between the vane and the rib during rotation of the drill bit within a fluid can produce fluid flow through the channel from the rib to the vane.
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