Abstract

A shaft enlargement arrangement for a boring system is provided, the shaft enlargement arrangement comprising a hollow column proximate a lower end of the boring system; a first cutter head that is rotatably fitted to the hollow column, with first drive means being provided to rotate the first cutter head relative to the hollow column so as to bore downwardly a hole having a diameter corresponding substantially to the diameter of the first cutter head; and a boring head arrangement fitted to an operatively lower end of the column, the boring head arrangement terminating in a second cutter head to bore a leading hole as the boring system proceeds to bore downwardly. In an embodiment, the first cutter head comprises a support body carrying a winged arrangement, the support body being rotatably fitted to the column, the winged arrangement comprising a plurality of wings extending from the support body, each wing being fitted with, or comprising, a plurality of first cutter elements.

IPC Classes  ?

• E21B 7/28 - Enlarging drilled holes, e.g. by counterboring
• E21B 27/00 - Containers for collecting or depositing substances in boreholes or wells, e.g. bailers for collecting mud or sand; Drill bits with means for collecting substances, e.g. valve drill bits
• E21D 5/04 - Lining shafts; Linings therefor with brick, concrete, stone, or similar building materials
• E21B 10/32 - Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers with expansible cutting tools
• E21D 1/08 - Sinking shafts while moving the lining downwards
• E21B 4/16 - Plural down-hole drives, e.g. for combined percussion and rotary drilling; Drives for multi-bit drilling units
• E21D 1/06 - Sinking shafts mechanically with shaft-boring cutters
• E21B 4/18 - Anchoring or feeding in the borehole
• E21B 12/06 - Mechanical cleaning devices
• E21B 15/00 - Supports for the drilling machine, e.g. derricks or masts
• E21B 17/10 - Wear protectors; Centralising devices
• E21B 19/00 - Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
• E21B 21/00 - Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
• E21D 1/03 - Sinking shafts mechanically

Abstract

A slot reamer head arrangement comprising a substantially rectangular body from which three reaming heads extend in line is provided. In an embodiment, a central reaming head is fitted to a drill string extending from a drilling machine, in use, and thus rotates, relative to the body, as the drill string rotates. The two further reaming heads are positioned on either side of the central reaming head, to define end reaming heads, and are also arranged to rotate relative to the body. In an embodiment, the central reaming head is arranged to rotate in a first direction, and the two end reaming heads on either side of the central reaming head are arranged to rotate in an opposite direction. In this regard, the body includes a gear arrangement to interconnect the two end reaming ends with the central reaming head. In an embodiment, each reaming head comprises three rotating cutters fitted to a triangular base that is rotatably mounted to the body.

IPC Classes  ?

• E21B 10/26 - Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers
• E21B 7/28 - Enlarging drilled holes, e.g. by counterboring
• E21B 10/62 - Drill bits characterised by parts, e.g. cutting elements, which are detachable or adjustable

Abstract

A raise boring method is disclosed including the steps of cutting a raise with a raise boring arrangement comprising a surface-mounted drilling unit from which a hollow drill string, comprising a plurality of hollow drill pipes fitted together, extends downwardly through a pre-drilled pilot hole, with a reamer head to cut the raise being fitted to the end of the drill string; stopping the cutting process; lowering a cable through the hollow drill string towards the bottom of the raise; fitting an inspection device at the bottom of the raise to the cable extending through the hollow drill string, the inspection device comprising a controller to receive data obtained by the inspection device; operating the inspection device so as to inspect the side wall below where the reamer head is cutting; communicating the data obtained by the inspection device to an inspection station; and determining whether maintenance is required on the side wall.

IPC Classes  ?

• E21D 3/00 - Raising shafts, i.e. working upwards from the bottom