| 摘要 |
<p>A locking device for use in an adjustable drill string stabiliser comprises a fluid reservoir (63) provided in a first body member (15), the reservoir being divided into two chambers by a sealing piston (44) secured on a second body member (6) movable relative to the first body member. The chambers of the reservoir are in fluid communication through a valve (53) which is actuable to close said fluid communication between the chambers and thus prevent relative movement of the body members. </p> |
