Ultra-High-Pressure Hydraulic Slitting Pressure Relief and Penetration Enhancement Technology and Equipment for Soft Coal Seams

<div>Gas flow around one borehole. (a) Schematic diagram of gas flow in ordinary boreholes. (b) Schematic diagram of gas flow in slotted drilling.</div>

Geofluids

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Figure 4

Figure 4: Ultra-High-Pressure Hydraulic Slitting Pressure Relief and Penetration Enhancement Technology and Equipment for Soft Coal Seams 