| 摘要 |
<p>Downhole Torque and Rate of Penetration are utilized to develop indications of formations that are porous, argillaceous or tight. This information is useful as an aid in selecting drilling practices and drilling bits. The method separates bit effects from lithology effects when drilling with roller cone or PDC bits by utilizing surface and subsurface wellsite sensors to determine averaged values of real time penetration rate and downhole torque. Changes in bit torque are used to broadly classify the lithology into three categories: porous, argillaceous and tight formations while trends in bit torque and rate of penetration in shale are used to separate wear of the bit from changes in formation strength.</p> |
