Cut Out Distance – A Critical Parameter for Mechanized Depillaring by Continuous Miner

Rakesh, Manthri; Dash, Ashish Kumar; Murmu, Sunny

doi:10.22044/jme.2025.15831.3045

Document Type : Original Research Paper

Authors

Department of Mining Engineering, National Institute of Technology Raipur, Raipur, India

10.22044/jme.2025.15831.3045

Abstract

India's growing energy demand has intensified the need for efficient and safe coal extraction methods, particularly in underground mining, where mechanized depillaring using Continuous Miner (CM) technology has gained prominence. This study explores the critical role of Cut-Out Distance (COD) in optimizing production and ensuring safety during mechanized depillaring operations. COD, defined as the stable drivage length that can be cut without support, directly impacts productivity, roof stability, and operational safety. Despite its importance, there are no standardized guidelines for determining COD in Indian coal mines, leading to trial-and-error practices that compromise efficiency and safety. This paper reviews global and domestic practices, highlighting the inadequacies in existing methods for COD estimation. It identifies key factors influencing COD, including Rock Mass Rating (RMR), roof elasticity, geological conditions, and machinery capabilities. The work also examines case studies of strata control failures in Indian coal mines, highlighting the consequences of improper strata assessment in mines. The research work advocates for the development of standardized guidelines tailored to Indian mining conditions by integrating numerical simulations and machine learning tools for precise COD estimation. A flow chart of methodology for the development of guidelines is proposed; the findings aim to enhance safety, reduce accidents, and improve productivity, paving the way for sustainable growth in India's underground coal mining sector.

Keywords

Main Subjects

Mechanized Excavation

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Journal of Mining and Environment

Cut Out Distance – A Critical Parameter for Mechanized Depillaring by Continuous Miner

References

References

Volume 16, Issue 5
July and August 2025
Pages 1591-1605

Cut Out Distance – A Critical Parameter for Mechanized Depillaring by Continuous Miner

References

References

Volume 16, Issue 5July and August 2025Pages 1591-1605

Volume 16, Issue 5
July and August 2025
Pages 1591-1605