Mine Laneway Research Articles

Study on the Shovel and Support Bracket’s Compensation for Vertical Pose’s Deviation of Roadheader

Automatic directional excavation technology in the coal mine laneway is the important research direction of integrated excavation project. Shovel and support bracket are the most key parts for keeping roadheader body stable in excavation. This paper studies the control ability and extreme position of boom-type roadheader’s shovel and support bracket, to calculate the adjustable vertical angles rang which is realized by shovel and support bracket, expanding roadheader’s automatic compensating excavation ability, meanwhile ensuring body stable. Vertical angle is one of the four kinds of basic body pose deviation parameters. This study is the research basis for the accuracy analysis of boom-type roadheader’s directional excavation. Because the depth that shovel and support brackets’ tip compress into laneway ground, is mainly determined by laneway ground hardness and body weight, and can’t be calculate accurately, paper’s end gives feedback control application of shovel and support bracket according to laneway conditions.

Study on the Section's Extreme Position of Roadheader's Cutting Arm in Coal Mine Laneway

Directional excavation technology in the coal mine laneway is the important research direction of integrated excavation project. This paper studies the changes of cutting section shape and boundary values caused by the swing of boom-type roadheader's cutting arm ​​to calculate the maximum values of compensable pose deviation when cutting, as the research basis for the accuracy analysis of boom-type roadheader's directional excavation. This paper gives the calculation method of cutting arm control, spatial modeling and analysis of cutting head position changes caused by cutting arm in thought of the three-dimensional analytic geometry, and also gives verification in the way of Matlab graphics simulation. At last, a control method to compensate section boundary by cutting arm is put forward.

Effect of Wind Speed to Water Mist in Coal Mine Laneway

There are many factors which affect the effectiveness of the gas explosion suppression by the water mist in the coal mine laneway. This paper studies the relationship between the wind speed and the status of the water mist by numerical analysis. The results shows, for gas explosion suppression in coal mine laneway, the water mist system must be arranged in the region that the wind speed is 5m/s or slower.

Ranging System in Coalface Based on Linear Frequency Modulation Signal

Based on technology of linear frequency modulation, constructed a wireless communication network in accord with the standard of IEEE 802.15.4a, which being fitted for using in mine. By method of symmetric double-sided two-way ranging, implemented a precise ranging and locating system for mines and tested it in indoor environment, which is similar to the straight laneway of mine and coalface. Result data show that the system has good performance in anti-jamming and anti-multi-path effects of electromagnetic wave and can communicate in a distance of 100m in laneway. The ranging accuracy is 1.5m, which well meeting the need of locating for person and equipment in mine.

Electromagnetic environments in roadways of underground coal mines and a novel testing method

The electromagnetic environment of laneways in underground coal mines is an important area for the design of new electronic products, as well as a fundamental space for mine monitoring, surveillance, communications and control systems. An investigation of electromagnetic interference in coal mines is essential for the enhancement of performances of these systems. In this study, a new field method is provided in which radiated emission tests in coal mine laneways have been carried out. We conclude that: 1) the wiring motor vehicles can radiate interference with a bandwidth up to 1 GHz and with an amplitude 10 dBμV/m higher than the background noise; 2) the PHS (Personal Handy phone System) mobile communication system can cause interference 40 dBμV/m higher than the background noise; 3) an interference 25 dBμV/m higher than the background noise can be generated during the communication at a working bandwidth of 48.8 MHz; and 4) power cables, battery vehicles as well as mechanical and electrical dong rooms have little effect on the electromagnetic radiation environment in coal mine tunnels.

Characteristic of geological anomaly detected by combined geophysical methods in a deep laneway of coal mine

The driving safety in deep laneway is often affected by many geological anomaly factors in ahead of a laneway end. The variability of rock properties, faults and so geological anomaly have relations with groundwater in rock mass. Therefore, it is necessary to employ various geophysical methods for geological anomaly detection in the front of laneway end in order to avoid mine inundation, which guides the process of driving in a laneway of coal mine. According to the comparative analysis between geological exploration and various geophysical methods used in the 2000m-passageway of −780-south section in Guqiao coal mine of Huainan, the result shows as follows. 1) The abnormity of lithology and faults can be detected and forecasted by the reflected seismic wave in the laneway, long distance prediction and high resolution detecting ability are the main characters of the reflected wave method, and the spectrum characteristics of seismic wave can distinguish the change of lithology; 2) The transient electromagnetic method (TEM) is very sensitive to solve the change of aquosity in terrane ahead of the laneway heading face, and the relatively characteristics between lithology change and its containing water can be identified finely through the direct current resistivity method in laneway; 3) The relatively characteristics between lithology change and its contained water can be identified finely through the direct current resistivity method in laneway. In a limited space of laneway, the combined analysis method using variety of geophysics methods are an effective method to detect geological anomaly and hydrogeology ahead of the laneway end, which can provide a powerful technology for safety and efficient driving in a deep laneway.

Integrative outburst prevention technique of high-pressure jet of abrasive drilling slotting

Coal and gas outburst is one main disaster in coal mine production, so it is very significant to prevent the coal and gas outburst effectively. Based on the stress-relief zone theory, we establish the stability condition of stress-relief zone in a coal mine laneway and find out the relationship between the stress-relief zone and the coal and gas outburst risk and analyze the function of stress-relief zone in preventing coal and gas outburst. The Technique of The High-Pressure Jet of Abrasive Drilling Slotting Integration combined with the techniques of The High-Pressure Jet of Abrasive Slotting and drilling is developed to prevent outburst. The combined new technique can improve the effective effected range of pressure relief zone around a single drilling-hole, which can reduce coal and gas outburst by combining "point" , "line", "surface", and "body" of the front of working face coal mass. The technique can reduce coal and gas outburst risk effectively and realize safe production. Practical engineering applications in YanJin NO.1 Mine of Chongqing Tianhong Mining Group indicate that this technique is effective, and can be applied to the relevant engineering projects.

The propagation law and analysis of gas explosion in U type duct

In order to explore the propagation law of gas explosion in U type laneways, the propagation law of flame and shock wave in U type duct were experimentally and theoretically investigated. It is shown that the shock wave takes on the complicated stress state and the flame takes on complicated change rules in the U type duct. The propagation process of gas explosion in bend duct is the mutual action of explosion wave, flame and complicate flow, the destruction in bend surface is especially serious. In the mine exploitation and laneway design, the bend laneway should be avoided, especially continuous bend laneway.