RELATIONSHIP BETWEEN THE FIGURES OF COAL DRAWING PARAMETERS AND THE EFFICIENCY INDICATORS OF THE TECHNOLOGY FOR MINING THICK COAL SEAMS

Original paper

UDC 004.942; 622.3 c A.N. Starodubov1, 2, 2025

ISSN 0041-5790 (Print) • ISSN 2412-8333 (Online) • Ugol’ – Russian Coal Journal, 2025, №12

DOI: http://dx.doi.org/10.18796/0041-5790-2025-12-77-82

Authors

A.N. Starodubov1, 2

1 Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences, 650065, Kemerovo, Russian Federation

2 T.F. Gorbachev Kuzbass State Technical University, Kemerovo, 650000, Russian Federation, e-mail: a.n.starodubov@gmail.com

Authors Information

Starodubov A.N. – PhD (Engineering), Associate Professor, Deputy Director of the Institute of Coal, Federal Research Center of Coal and Coal Chemistry of Siberian Branch of the Russian Academy of Sciences, Kemerovo, 650065, Russian Federation; Associate Professor, T.F. Gorbachev Kuzbass State Technical University, Kemerovo, 650000, Russian Federation, e-mail: a.n.starodubov@gmail.com

Abstract

The first characterization of flow zones in granular materials was performed in physical models developed to study silo design. The theory of ore discharge assumes particle outflow from volumes close to ellipsoids of revolution; during release, a loosening ellipsoid and a discharge funnel form, defined by major and minor semi-axes. In the examined technology of under-roof coal release using powered supports with controlled discharge to the face conveyor, a similar pattern is observed. However, due to multiple advance steps and support of coal from above and by heavier waste rock from the caved area, the drawbody shape distorts toward the face advance. To ensure complete discharge and minimize coal loss in the caved zone, the advance distance must align the drawbody boundary with the coal mass turn line. The relationship between advance distance and ellipsoid dimensions is shown; maximizing their match yields the best efficiency indicators.

Keywords

Discrete element method, computer simulation, underground mining, under-roof coal outlet, powered roof support, figures of coal drawing, powerful coal seam, longwall mining operations.

References

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Acknowledgements

The work was performed within the framework of the state assignment of the Federal Research Center of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences, Project FWEZ-2024-0024 “Development of efficient technologies of coal mining by robotic mining complexes operating without permanent presence of personnel in mining zones, design of control systems and methods to assess their technical condition and operating life as well as justification of the mineral resource base reproduction. 2024-2025” (Reg. No. 124041100071-9).

For citation

Starodubov A.N. Relationship between the figures of coal drawing parameters and the efficiency indicators of the technology for mining thick coal seams. Ugol’. 2025;(12):77-82. (In Russ.). DOI: 10.18796/0041-5790-2025-12-77-82.

Paper Info

Received October 3, 2025

Reviewed November 15, 2025

Accepted November 28, 2025