The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of co...The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of conveyor system are studied, and their calculating models are built up.展开更多
Reliability and maintainability of mining industry is more in focus than ever, and the mining systems are becoming more complex and the equipment more expensive to repair or modify. Unplanned failures can result in si...Reliability and maintainability of mining industry is more in focus than ever, and the mining systems are becoming more complex and the equipment more expensive to repair or modify. Unplanned failures can result in significant costs, especially when the machinery is hard to repair or spare parts are far away. This paper presents a case study describing a reliability and maintainability analysis of the main conveyor system of the Svea Coal Mine located in Svalbard, Norway. The conveyor system includes several separate conveyors. In this study, the main six conveyors of the whole system were selected for the analysis. The failure and repair data of the conveyors were collected for the whole year of 2010 using maintenance and daily reports. The date was analyzed and the result shows that the availability of six conveyers is 96.44%for one year of operation. However, reliability of these conveyers needs to be improved in order to reduce the number of failures.展开更多
The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis ...The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire.展开更多
This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer...This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics.展开更多
文摘The key technology of semi-continuous conveyor system decides the successful using of this system. The key technology includes optimal initial building depth of this system,the crusher moving step and the layout of conveyor system are studied, and their calculating models are built up.
文摘Reliability and maintainability of mining industry is more in focus than ever, and the mining systems are becoming more complex and the equipment more expensive to repair or modify. Unplanned failures can result in significant costs, especially when the machinery is hard to repair or spare parts are far away. This paper presents a case study describing a reliability and maintainability analysis of the main conveyor system of the Svea Coal Mine located in Svalbard, Norway. The conveyor system includes several separate conveyors. In this study, the main six conveyors of the whole system were selected for the analysis. The failure and repair data of the conveyors were collected for the whole year of 2010 using maintenance and daily reports. The date was analyzed and the result shows that the availability of six conveyers is 96.44%for one year of operation. However, reliability of these conveyers needs to be improved in order to reduce the number of failures.
文摘The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire.
基金jointly supported by the China National Science Foundation under Grant Nos.41875172 and 42075192。
文摘This paper studied a snow event over North China on 21 February 2017,using aircraft in-situ data,a Lagrangian analysis tool,and WRF simulations with different microphysical schemes to investigate the supercooled layer of warm conveyor belts(WCBs).Based on the aircraft data,we found a fine vertical structure within clouds in the WCB and highlighted a 1-2 km thin supercooled liquid water layer with a maximum Liquid Water Content(LWC) exceeding0.5 g kg^(-1) during the vertical aircraft observation.Although the main features of thermodynamic profiles were essentially captured by both modeling schemes,the microphysical quantities exhibited large diversity with different microphysics schemes.The conventional Morrison two-moment scheme showed remarkable agreement with in-situ observations,both in terms of the thermodynamic structure and the supercooled liquid water layer.However,the microphysical structure of the WCB clouds,in terms of LWC and IWC,was not apparent in HUJI fast bin scheme.To reduce such uncertainty,future work may focus on improving the representation of microphysics in bin schemes with in-situ data and using similar assumptions for all schemes to isolate the impact of physics.
