| 摘要 |
<p>A well drilling assembly of the type in which a rotary device is attached to a drawworks, for example to the hoisting hook on a derrick, to which rotary device a hollow shaft (13) is coupled, having a threaded end which is adapted for connection to a complementary threaded end on the drill string, and wherein a clamping/lifting means known as an elevator (38) is suspended below the rotary device by two hanger struts (37). The shaft (13) connected to the rotary device is telescopic. Outside the shaft a lifting means (24, 25, 40) is provided for the lower part (21) of the telescopic shaft. The two hanger struts (37) which carry the elevator (38) for one end of the pipe are axially movable in relation to the telescopic shaft (13) by means of a sliding holder (35) known as a link hanger. The link hanger (35) is axially movable by means of hydraulic cylinders (42,43).</p><p>The lifting means for the lower part of the telescopic shaft consists of hydraulic cylinders .(24, 25) which are constructed as a unit together with the hydraulic cylinders (42, 43), the cylinders (24, 25) constituting piston rods for the hydraulic cylinders (42,43).</p> |
