General methodology for the optimization of the parameters of aggregated tunneling systems

Задков

Kuzkin

et al. 2020

KEM

The paper analyzes the structure of coal beds. It is noted that coal beds belong to laminar massifs with characteristic oriented structure and pronounced anisotropy of strength properties, and include rock layers and consolidated hard inclusions. The quality criteria of the coal loosening process are highlighted. A selective method of separating coal from a massif by cutting along weakened surfaces is proposed as an alternative to the existing combine technology with continuous cutting of a massif from the surface.

Section: Figure 2 Cutting Force Dependencies On Shear Angle To the Di...mentioning

confidence: 99%

Fractured-Laminar Structure of Formations and Methods of Coal Loosening

Задков

Kuzkin

et al. 2020

KEM

“…The theory of highest stresses suggests that the yield strength of plastic materials begins when the stress reaches a critical level [30,31]. It is believed that the separation of coal from the rock mass in time proceeds similarly to the mechanical processing operation of various materials.…”

Section: Introductionmentioning

confidence: 99%

Increasing the content of coarse fractions in the mined coal mass by a combine using paired cuts

Xuan²,

Задков

et al. 2022

PMI

The main volume of coal is mined underground using shearers. In modern shearers, auger actuators are mainly used, which are distinguished by the simplicity of design, manufacturability and reliability. However, in the process of separating coal from mass by cutting, the yield of fine grades is 40-50 % of the total production volume. Therefore, the search and development of technical solutions that provide an increase in the yield of large fractions in the process of coal mining with auger shearers is an urgent task. Traditionally, this problem is solved by increasing the thickness of the slices, which is achieved by installing cutters with a larger radial reach and increasing the shearer feed rate. An unconventional way to increase the cross section of slices by forming energy-efficient paired and group slices with mutual superposition of stress fields in the mass from the action of neighboring cutters is considered. The results of modeling the process of cutting coal confirm that an increase in the efficiency of destruction of the rock mass by the cutters of the auger executive bodies of the shearer can be achieved by a complex technical solution, including the formation of paired cuts and combined stress zones in the rock mass. As a result, the output of large fragments when cutting with paired cutters increases by 1.3-1.8 times compared with cutting with a single cutter.

“…The mining of high-tech coal seams in countries with a developed mining industry is carried out mainly by long complex mechanized treatment faces equipped with dual auger shearers [1][2][3][4][5] with symmetrical layout. Such shearers can work on one-sided with stripping and shuttle schemes of coal extraction, with self-cutting into a seam on a new strip of excavation by oblique drives.…”

Section: Introductionmentioning

confidence: 99%

Evaluating the Efficiency of Coal Loading ‎Process by Simulating the Process of Loading onto the Face Conveyor with a Shearer with an ‎Additional Share

Xuan

Lykov

et al. 2021

IJE

This paper analyses the possibility of increasing the efficiency of loading the destroyed rock mass into the face scraper conveyor by the lagging screw actuator of the shearer in the process of coal mining in the complex mechanized treatment faces of coal mines. It was taken into account that the most significant influence on the loading efficiency of coal is exerted by the dimensions of the cross-sectional area of the loading window, the distance between the screw and conveyor and the height of the bottom of the conveyor. Non-traditional technical solutions are proposed that reduce the negative impact of the gap between the screw and the conveyor on the efficiency of coal loading by the lagging screw actuator of shearers and increase the degree of filling of the conveyor groove. Technical solutions contribute to the formation of a rational section of the cargo flow in the trough of the downhole conveyor and, therefore, increase its productivity. The results of modeling the process of loading coal onto the face conveyor by an auger actuator with an additional loading device are presented. Evaluation of the effectiveness of the proposed constructive technical solutions for the interface unit in the loading area confirmed an increase of 2.94 times the maximum capacity of the screw executive body for loading coal onto the face conveyor while 2.7 times less specific energy consumption during loading.