| 摘要 |
<p>The present invention provides a drilling assembly and method that is especially useful for a bottom hole drilling assembly for drilling a borehole through an earth formation. In one embodiment, the drilling assembly is preferably comprised of a tungsten alloy which is sufficiently plastic to be able to withstand the bending, torsional, and compressive stresses which occur in a bottom hole drilling assembly. The tungsten alloy weight section may be axially moveable with respect to an outer tubular and when mounted within the bottom hole assembly, acts to place the outer tubular in tension to provide a stiffer bottom hole assembly.</p> |
