| 摘要 |
<p>MEASURING WHILE DRILLING TOOL A measuring while drilling tool is disclosed. The preferred embodiment incorporates an outer shell which is connected in a drill string above the drill bit and among the drill collars. The apparatus utilizes mud pressure variations to pump oil with a piston to energize a closed hydraulic circuit. The oil is delivered via a distribution and manifold system to first fill and scan five hydraulic signals sequentially. The sequential scan of the five hydraulic signals is then conveyed to an output mechanism comprising a choke which is placed in the lower end of the tool which choke varies the mud throughput, thereby varying upstream pressure in the mud circuit, forming an output which can be detected at the surface.</p> |
