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We هي شركة ذات تقنية عالية تدمج البحث والتطوير والإنتاج والتوزيع ، وتوفر كسارة ، وصنع الرمال ، ومعدات طحن ، ومحطة تكسير متنقلة ، إلخ.
We هي شركة ذات تقنية عالية تدمج البحث والتطوير والإنتاج والتوزيع ، وتوفر كسارة ، وصنع الرمال ، ومعدات طحن ، ومحطة تكسير متنقلة ، إلخ.
The three-dimensional gas prevention and control method constructs a new gas control model for single thick coal seams with high gas outburst risk and realizes the all-round احصل على السعر
201681 These applications include mine geology, outburst risk mitigation through regional and localized stress reduction in multi-seam mining of low permeability, outburst احصل على السعر
2023101 • Thorough analysis of the historical evolution of outburst indicators • Intelligent algorithms excel in uncertain static prediction and dynamic gas emission • احصل على السعر
with the combination of underground kilometer drilling rig drilling, cross layer drilling and bedding drilling", "surface well pre drainage of coal seam gas" and "underground cross احصل على السعر
2022928 This study enriches the theory and methods of safety management in deep coal mines, and effectively helps coal mine enterprises in improving their ability to manage coal–gas outburst risks.احصل على السعر
2020630 3.2 Regional outburst prevention method for coal roadway strip. According to the energy source analysis of dynamic disasters, the outburst prevention method in احصل على السعر
20231031 Through the study of various outburst prevention measures in the pre-drainage gas area such as surface drilling, bedding (directional) drilling, and crosslayer احصل على السعر
The results show that the geological conditions and mining conditions are highly complicated compared to other countries; coal seams in China have characteristics of high ground احصل على السعر
20191218 rapid detection of outburst prevention effect of CUCS. Hence, in this , a laboratory system for testing the relationship between IRGEB and coal seam احصل على السعر
2021616 Pressure relief drilling is one of the most common techniques to reduce the impact of rock burst, but the useful dynamic phenomena in the drilling process are ignored due to the lack of corresponding technical methods. Based on the fact, an innovative measurement method for vibration signals during the drilling construction by pneumatic احصل على السعر
202199 Coal and gas outbursts can lead to serious disasters in coal mines. The drilling of boreholes to predrain the gas is an effective measure for preventing such accidents. However, due to the complexity of the احصل على السعر
202388 It can be seen from Figures Figures13 13 and and14 14 that the average concentration of directional drilling gas drainage in the coal mining area is 80.15%, and the average concentration of directional drilling gas drainage in the non-coal mining area is 67.46%; the average net amount of the directional drilling gas drainage in the coal cuttingاحصل على السعر
2021111 An example study was conducted on a mine of a large state-owned coal mine enterprise in Shaanxi Province, China. The results show that the method helps coal mine enterprises to accurately assess gas explosion risks, identify weak links in risk prevention and control, and provide a powerful means for continuous improvement of risk احصل على السعر
2020324 However, for the coal seams with high outburst risk, these methods fail to meet the demands of high‐yield and high‐efficiency coal recovery as well as safe, green, and economical coal mining.احصل على السعر
2022429 In order to solve the problem that the gas in the upper corner is easy to exceed the limit in the mining process of the deep outburst coal seam. Based on the theory of “O-ring” and the distribution of stratigraphy in the field, the development law of mining fissures in the overlying rock layer during the workface retrieval was احصل على السعر
2017918 Despite the hazards surrounding coal production, China has produced remarkable results in the past 10 years, although some limitations regarding methods adopted in the country exist compared with those used in the USA, Australia, etc. (Li and Huang 2010; Zhang et al. 2016a).Economic development and exponential population احصل على السعر
2023111 The designed production capacity of Hudi Coal Mine is 60 × 10 4 t/a, and the No. 3 coal seam was currently mined with the risk of coal and gas outbursts. The column diagram of coal seams in Hudi Coal Mine is shown in Figure 1B.The gas content and pressure of No. 3 coal seam is 14.48–24.56 m 3 /t and 1.24–3.83 MPa, respectively. Due احصل على السعر
2022218 The integrated drilling and stamping equipment for through-seam gas extraction and production can be implemented as a local outburst prevention measure with a wide range of applications, such as increasing the gas production from hard coal, soft and hard seam coal, and a combination of soft coal and surrounding rock.احصل على السعر
2023726 Affected by tectonics, soft and hard composite coal seams are widely distributed in China; the soft stratification in the soft and hard composite coal seam is the key to controlling the occurrence of coal and gas outburst accidents. Based on this, for soft and hard composite coal seams, in order to accurately extract soft layers, a directional احصل على السعر
2022622 Coal will continue to play an important role in China’s economic development and social development in the coming decades. However, due to the complex distribution conditions of coal resources, the mining of coal resources is subject to various restrictions. Coal and gas outburst is an important issue in coal mining, and the threat to احصل على السعر
2023930 regional outburst prevention drilling holes in each coal seam whose thickness is greater than 0.3m, and the borehole layout parameters are the same as the aboveاحصل على السعر
2021710 Coal and gas outburst is one of the major disasters in the safety production of coal mine. According to the mechanism of coal and gas outburst, based on the comprehensive analysis of various influencing احصل على السعر
201864 1 Current status of underground drilling equipment at home and abroad. At present, the drilling capacity of underground drilling equipment in coal mines has grown to more than 2 000 m and has evolved from a single split structure to multiple models such as crawler and directional drilling rigs. The specifications and varieties of drilling toolsاحصل على السعر
zation and intelligent development of coal mines and is the development direction of coal and gas outburst prediction and early warning technology. Therefore, this work stud-ies the Xinjing Coal Mine and, based on the mine produc-tion process, geological data, and more than 200 historical gas-dynamic phenomena, comprehensively analyzes the mul-احصل على السعر
2022616 CH4 is the second-largest greenhouse gas and has a significant impact on global warming. China has the largest amount of anthropogenic coal mine methane (CMM) emissions in the world, with coal mining emissions (or gas emissions) accounting for 90% of total energy industry emissions. The results of CH4 emission inventories from previous احصل على السعر
202159 The mechanism of coal and gas outbursts tends to be more complex after entering the deep part of a coal mine from the shallow ground. As deep coal roadway outbursts change from gas-dominated to geostress-dominated, it is imperative to explore how to prevent outbursts of deep geostress-dominated coal roadways. Because the احصل على السعر
201821 Prediction is the first step to prevent and control coal outburst geological disasters. Generally, both limits and disadvantages are generated for the traditional prediction methods of drill cuttings from a Φ42 mm borehole with increased mining depths. To investigate the discharge law of drill cuttings and improve the prediction index, احصل على السعر
2022622 mines. Keywords: gas outburst; coal seam; green mining; gob-side entry retaining; layer-by-layer gas extraction 1. Introduction Gas protrusion mines account for about half of the coal mines in China. Gas is the biggest threat to coal mine safety, and more than 70% of major safety accidents in coal mines nationwide are related to gas explosions.احصل على السعر
2022720 This shows that protective layer mining of the #7 and #8 coal seams combined with surface drilling to extract pressure-relief gas can protect the #2 and #3 coal seams. Layout of drilling holesاحصل على السعر
