| 摘要 |
<p>The present invention relates to a navigation system for navigating a drill head out of or in collision with a casing in a first borehole. The system comprises a drill head drilling a second borehole; a drill string made of several tubulars mounted into one tubular string by means of a connection means, the drill head being mounted onto one end of the drill string; and a plurality of logging units arranged with one logging unit in or in relation to each connection means. Each logging unit comprises a data transmitter and a data receiver for sending and receiving data between the logging units; and a detector, at least one logging unit comprising an emitter. Furthermore, the invention relates to a navigation method using the navigation system.</p> |
