Research and Field Application of a Down-Dip Withdrawal Method for Heavy Fully Mechanized Hydraulic Supports in a Steeply Inclined Longwall Face

Xiuyuan He; Renrui Li

doi:10.63313/AERpc.9101

Authors

Xiuyuan He School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo Henan 454003, China Author
Renrui Li School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo Henan 454003, China Author

DOI:

https://doi.org/10.63313/AERpc.9101

Keywords:

Retrieval of heavy supports in coal mines, Technology, Reasonable optimization

Abstract

The down-dip withdrawal of heavy hydraulic supports under a large face inclination remains a bottleneck affecting the safety and efficiency of longwall face relocation. In this study, a down-dip withdrawal technology for heavy fully mechanized hydraulic supports was developed and field-tested at the 2091 working face of No. 6 Coal Mine, Hebi Coal Company. The coal-pillar layout during the closing stage was optimized to improve the coal recovery ratio and reduce resource losses. The pre-withdrawal support scheme, including a flexible-mesh artificial roof, was redesigned to enhance roof stability during the withdrawal period. The withdrawal process was also optimized to enable parallel operations of support alignment, loading and disassembly. Mechanized withdrawal equipment was introduced to address the anti-overturning and anti-sliding requirements during top-to-bottom transportation of fully mechanized supports, thereby realizing safe and mechanized support withdrawal. Field application showed that the face relocation time was reduced by 55%, while labor intensity, production cost and the risk of spontaneous combustion were substantially decreased.

References

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