Ship carried offshore drilling system - has drill assembly guided into hole by funnel on seabed

摘要

The drill assembly is lowered via a cable and led in through a guide funnel on the sea bed into the guide tube and thus positioned in the desired attitude for the drilling, e.g. at angles or straight. Preferably the adjusting legs of the funnel can be controlled from the service console to achieve the drilling direction. Power reaches the drill preferably through hydraulic sleeves or compresses air sleeves or again through an electric cable, depending on the type of drill motor employed. A flexible shaft may power the drill, all of these led from the ship to the drill through the funnel. Disbalancers should similarly be employed to promote the advance of the drill, these mounted at right angles to the drill axis. Reduction gearing should be accommodated in the drill assembly, with stabiliser fins thrusting against the casing to support the drill torque.