Research on Influencing Factors of Effective Gas Extraction Radius in Coal Mine Based on Multiple Linear Regression

Table 10

Parameters of extraction borehole.

Design angle (°)	Design inclination (°)	Drill hole see coal hole depth (m)	Drilling depth (m)	Hole diameter (mm)	The construction of the place	Height of opening (m)
−90.0	90.0	14.5	Not less than 1 m	94	2616 bottom roadway	The center line is 0.5 m to the right