| 摘要 |
<p>A downhole centralizer is provided for positioning along a drill pipe string passing through a deviated well bore. A centralizer body (14) is connected to an upper sub (12) by a plurality of lobe-shaped connectors (32,38) which permit angular deviation of the central axis of the upper sub with respect to the central axis of the centralizer body. The centralizer body is preferably connected to a lower sub (16) by similar lobe-shaped connectors (46,44). The opposite ends of each of the upper and lower subs are threaded for fixed enagement with respective upper (20) and lower (26) pipe joints in the tubular string. A flexible flow conduit (48) is positioned within a passageway through the centralizer body, and a pair of upper and lower sealing member (50) are provided to maintain sealed engagement between the respective upper and lower subs and the flow conduit for transmission of fluid through the centralizer. The centralizer of the present invention may be reliably used to center the tubing string within the deviated portion of a borehole, thereby reducing torque losses to the drill bit and wear on the drill string.</p> |
