GB1141491A - Earth and rock drilling apparatus - Google Patents

Abstract

1,141,491. Boring earth etc; submerged offshore platform. I. FINN 18 April, 1966 [8 May, 1965; 14 July, 1965], Nos. 19517/65 and 29759/65. Headings E1F and E1H. Drilling or tunnelling apparatus comprises an external member 2 having an internal helical vane 4, and an internal member 1 having external helical vane 3 of opposite hand to that of the vane 4, the members being relatively rotatable. Fluid pumped down the member 1 assists passage of spoil along the vanes, the spoil being classified before discharge by screens 15, 15a. The apparatus is fed by pinions 29 engaging fixed racks 27. Lengths of the members are added to increase the hole depth, and a pair of the lengths may be jointed and include rams to permit deflection of the hole or to enlarge the hole conically. In a modification (Fig. 5, not shown) the cutting edges of the members are replaced by motor driven cutters, the cutters of the outer member being mounted on pivoted arms to permit withdrawal of the apparatus after the hole has been lined. The apparatus is fed by motor driven pinions which engage racks fixed to the wall of the hole, and a lift is provided in the inner member to permit access to the cutters. In a submergible sub-aqueous drilling apparatus shown in Fig. 8, a series of drills 131 according to Fig. 1 are movably mounted in a rectangular frame 123 which is longitudinally movable within a rectangular enclosure 102 having walls formed by tanks 103, 109. When the tanks are full the drilling apparatus rests on teeth 116 having a seal 117, so that the enclosure may be pumped dry. In the tunnelling apparatus drawn in Fig. 9 the member 2 which carries a ring of motor driven cutters 172 is fed by a sleeve 175 which is urged forwards by jacks 176 engaging segmental tunnel lining 171 on which is fixed rails 185 reacting the torque from drilling.