摘要 |
An apparatus for cutting a deep slot, having a large depth to thickness ratio, in earth formations, which includes two main components, a motive means and a cutting assembly; the motive means, such as a crawler tractor, supports the projecting end of the cutting assembly, supplies a small portion of the driving force needed to advance the cutting assembly, and provides, through various connections, power, control functions, and the fluids required for operation of the cutting assembly; and the cutting assembly, extending the full depth of the slot along its advancing edge, includes an elongated support, a reciprocating cutter bar mounted on the leading edge of the support, a passage incorporated in the support for transmitting a fluid, generally a high gel strength clay paste, along the support and discharging the fluid in the interior of the slot, in a sufficient amount and under sufficient pressure to resist the earth pressure tending to close the slot and to provide a major portion of the force necessary to move the cutting assembly forward against the advance edge of the slot.
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