| 摘要 |
<p>An apparatus and method for use during earth boring operations when a wireline instrument is positioned within the drill string while drilling fluid is circulated, such as during directional drilling. The apparatus includes a circulating head connected to the top of the drill string that is connected to the drilling fluid pump. A wireline sealing apparatus is connected to and extends partially into the inner passage of the circulating head. The wireline sealing apparatus is of the type that has a flow tube closely fitted about the wireline and in communication with grease supplied under high pressure. The grease provides a seal while the line is stationary and while moving. Consequently, after the wireline instrument reaches the bottom of the drill string, the wireline may be pulled upward while drilling fluid is being circulated to remove slack. The wireline instrument also may be lowered and retrieved while drilling fluid is being circulated.</p> |
