Research on the Coal Seam Permeability-Increasing Technology via High-Pressure Water Jet Reaming and Its Application

Table 1

Verification of hole drilling parameters.

Borehole number	Opening position	Dip angle (°)	Azimuth (°)	Length (m)	Remarks
J1	0.5 m area of the K1 opening point	86.3	233.5	34	K1: 3.5 m
J2		75	217.5	35.2	K1: 4 m
J3		78.9	183	35	K1: 5 m
J4	0.5 m area of the K4 opening point	71.3	176.4	37.5	K4: 3.5 m
J5		60.6	176.4	40.7	K4: 4 m
J6		65.3	189	39.1	K4: 5 m
J7	0.5 m area of the K5 opening point	69.8	125.2	40.3	K5: 5 m
J8		61.4	125.2	42.8	K5: 5 m