Network Design Mode of In-Seam Gas Extraction Parameters Using Mathematical Modelling—Take Tangan Colliery as an Example

Table 2

Division of extraction units and preextracted time in the working face.

Extraction unit	1	2	3	4	5	6
Distance from open-off cut/m	2100~1670	997~696	696~491	491~345	345~242	242~0
Predrained time	350	242	169	119	83	58