A new 122 mm electromechanical drill for deep ice-sheet coring (DISC): 2. Mechanical design

The deep ice-sheet coring (DISC) drill consists of four major mechanical drilling subsystems and four subsystems supporting on-surface activities. The mechanical drilling subsystems are a drill sonde, a drill cable, a tower and a winch. The drill sonde is the down-hole portion of the drill system and consists of six distinct sections: (1) the cutter head, (2) the core barrel, (3) the screen section, (4) the motor/pump section, (5) the instrument section and (6) the upper sonde, which includes anti-torques and drill cable terminations. The drill cable not only provides the means of supporting the drill sonde in the borehole, but also provides conduits for electrical power and data transmission. The tower tilts to allow the drill sonde to be serviced in the horizontal position without removing it from the tower. The winch provides a means of quickly raising the sonde from the borehole and providing the fine control necessary for coring operations.