METHOD FOR AUXILIARY TUNNELING BY MEANS OF FREEZING SHAFT-SINKING CARBON DIOXIDE PHASE CHANGE CRACKING AND DEVICE THEREFOR

摘要

Disclosed is a directional CO₂ cracker. Two rows of directional energy discharge openings (1, 1') are distributed at both sides of an energy discharge head thereof in the axial direction, and the phase angle of the two rows of directional energy discharge openings (1, 1') is less than 180 degrees; in a freezing shaft-sinking process, a plurality of directional CO₂ crackers are arranged on the outer periphery of a working face, and a plurality of common CO₂ crackers are arranged on the inner periphery of a wellbore; the directional energy discharge openings (1, 1') at the both sides of the energy discharge head of each of the directional CO2 crackers respectively face the directional CO₂ crackers adjacent thereto; the directional CO₂ crackers in an outer-ring borehole (3) are detonated first, and then, the common CO₂ crackers in an inner-ring borehole (4) are detonated; the directional CO₂ crackers in the outer-ring borehole (3) direct energy to be released along the directional energy discharge openings (1, 1'), and blasting cannot disturb a wall structure outside the wellbore; after the outer-ring borehole (3) is blasted, a communicating weak surface is formed among the outer-ring boreholes (3), and the entire outer-ring boreholes (3) form a protective ring; and when the inner-ring borehole (4) is blasted, the protective ring formed by the outer-ring boreholes (3) cuts off the propagation of blasting energy to the wellbore wall, and the disturbance thereof to the wellbore wall structure is reduced.