GB631094A - Improvements in or relating to mining and excavating - Google Patents

Abstract

631,094. Mining and excavating. AMALGAMATED TIN MINES OF NIGERIA, Ltd. (Aston, C. P. T., and Wildi, C.). June 26, 1944, No. 12145. [Classes 68 (i) and 85] In the mining or excavating of underground material in which a pipe is sunk into the material and a stream of water is directed on to the material to disintegrate it and carry it in suspension towards and up the pipe, the stream of water is provided by one or more jets disposed above the level of the inlet opening of the upcast pipe. In Fig. 1, a sinking unit 18 passes through a stuffing gland 24 in a metal apron 23 held by projecting annular flanges 25, Fig. 2, engaging the ground, the unit 18 being oscillated by an engine 28 and belt 26 ; water under pressure is supplied to the unit by a pump 35 and passes out through pipe 38 with the spoil. The sinking unit may comprise a main pipe 29, Fig. 2, with a serrated lower end 39, and an upcast pipe 30, the space between the pipes being closed at the lower end by a plate 32 with a jetting nozzle 33. In hard ground, the borehole may be formed by ordinary boring means. When a desired stratum is reached, the sinking unit is replaced by an excavating unit comprising a similar main pipe 41 and upcast pipe 42, Fig. 7, but having the nozzle 33 replaced by an horizontal nozzle 45 arranged radially or at an angle to the radius ; if desired, air may be admitted round the excavating unit through a pipe 46 to provide an air space in which the nozzle 45 operates. A submersible or other pump may assist delivery through the upcast pipe, or such pipe may be provided with a Venturi constriction 48, Fig. 9, through which water is forced by a pump 50 and nozzle 49 ; in another form, Fig. 11, the Venturi constriction 48 in the upcast pipe has at its lower end nozzles 52 through which flows pressure water from the main pipe 41, pipe 41 also having sinking and excavating nozzles 54, 53, with valve control operated from above ground. A combined sinking and excavating unit may be provided having a nozzle adjustable for vertical or horizontal jetting. The units may be mounted on pontoons or endless track vehicles or supported by cranes &c. The units may be built of stepped sections with the smallest section at the bottom. Similar apparatus may afterwards be used to fill the cavities.