| 摘要 |
<p>The bar (10) has telescopable pipe elements e.g. inner pipe element (1'), center pipe element (1'') and lower pipe element (1'''), arranged into each other in a radial direction and movable against each other in an axial direction. A level arm-connection unit connects the bar with a telescopable drill pipe (50), and a tool-connection unit connects the bar with a drilling tool. The level arm-connection unit and the tool-connection unit are arranged in the inner- and lower pipe elements, respectively. A retaining unit supports the pipe elements in a drillhole mouth. Independent claims are also included for the following: (1) a drilling device comprising a tower (2) a method for forming a drill hole.</p> |
