摘要 |
<p>A disconnection sub for connection into a drill string comprises an upper body 2 and a lower body 3, and is configured so that torque can be transferred from the upper body 2 to the lower body 3 possibly by use of fingers 4 which engage in recesses 5. The upper 2 and lower 3 bodies are axially coupled by means of an axial coupling, possibly in the form of a sleeve 8 that is arranged to fracture when placed under a predetermined tension. Once fractured, the upper body 2 can be separated from the lower body 3.</p> |