Sequential extraction technology for high-intensity super-long two-entry longwall panels

The paper intends to comprehensively solve the problem of the low recovery rate of super-long two-entry longwall panels, difficulty maintenance of secondary mining roadway and need to jump in the gob-side entry.First of all, the patent put forward “A Gob-Side Entry Driving Method in Super-long Working Face”, and determined several key parameters.Secondly, the paper adopts the methods of theoretical analysis and field measurement to determines that the gob-side entry is arranged at a distance of 12 m away from the goaf.The distance of heading face behind the working face isn’t less than 1 200 m, and that ahead of the next face is not less than 190 m.The method can avoid mutual interference in the mining.Finally, under the conditions of actual engineering background, it determined the 40 m coal pillar in the original method and occurred large deformation in the secondary mining roadway, which can not meet the production requirements.If roadways use the roadway driving technology, it will be getting huge economic benefits.The conclusion can provide certain reference for the mine with similar geological and mining technology conditions.