Rational cutting height for large cutting height fully mechanized top-coal caving

来源 :Mining Science and Technology | 被引量 : 0次 | 上传用户:ffgghhaz
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Large cutting height fully mechanized top-coal caving is a new mining method that improves recovery ratio and single-pass production. It also allows safe and efficient mining. A rational cutting height is one key parameter of this technique. Numerical simulation and a granular-media model experiment were used to analyze the effect of cutting height on the rock pressure of a fully mechanized top-coal caving work face. The recovery ratio was also studied. As the cutting height increases the top-coal thickness is reduced. Changing the ratio of cutting to drawing height intensifies the face pressure and the top-coal shattering. A maximum cutting height exists under a given set of conditions due to issues with surrounding rock-mass control. An increase in cutting height makes the top-coal cave better and the recovery ratio when drawing top-coal is then improved. A method of adjusting the face rock pressure is presented. Changing the cutting to drawing height ratio is the technique used to control face rock pressure. The recovery ratio when cutting coal exceeds that when caving top-coal so the face recovery ratio may be improved by over sizing the cutting height and increasing the top-coal drawing ratio. An optimum ratio of cutting to drawing height exists that maximizes the face recovery ratio. A rational cutting height is determined by comprehensively considering the surrounding rock-mass control and the recovery ratio. At the same time increasing the cutting height can improve single pass mining during fully mechanized top-coal caving. Large cutting height fully mechanized top-coal caving is a new mining method that improves recovery ratio and single-pass production. It also allows safe and efficient mining. A rational cutting height is one key parameter of this technique. media model experiment were used to analyze the effect of cutting height on the rock pressure of a fully mechanized top-coal caving work face. The recovery ratio was also studied. The the cutting height increases the top-coal thickness is reduced. Changing the ratio of cutting to drawing height intensifies the face pressure and the top-coal shattering. A maximum cutting height exists under a given set of conditions due to issues with surrounding rock-mass control. An increase in cutting height makes the top-coal cave better and the recovery ratio when drawing top-coal is then improved. A method of adjusting the face rock pressure is presented. Changing the cutting to drawing height ratio is the technique used to c ontrol face rock pressure. The recovery ratio when cutting coal exceeds that when caving top-coal so the face recovery ratio may be improved by over sizing the cutting height and increasing the top-coal drawing ratio. An optimum ratio of cutting to drawing height exists that maximizes the face recovery ratio. A rational cutting height is determined by comprehensively considering the surrounding rock-mass control and the recovery ratio. At the same time increasing the cutting height can improve single pass mining during fully mechanized top-coal caving.
其他文献
学术写作亦是建构作者身份的行为。作者在展示研究过程和研究发现的过程中,不可避免地会在学术语篇中表露出自己的观点、立场,建构作者身份。已往研究表明作者会通过不同的语言
感应加热技术是利用电磁感应原理,通过交变电流在工件中产生涡流来加热工件的。由于感应加热具有加热速度快、发热在物料内部和热效率高、温度控制精度高、加热均匀、产品质
党的十八大以来,以习近平总书记为核心的党中央将反腐倡廉工作推向了一个新的阶段。中央纪委监察部网站是中国政府专门针对反腐工作成立的最具权威性的官方媒体网站,是党和政府
目的:研究不同浓度乙烯利对广西莪术及桂郁金产量和品质的影响。方法:在生长后期,用20~200mg/L的乙烯利进行叶面喷施,水为对照,取样检测根系伤流量、叶绿素含量、广西莪术和
ZL胶粉聚苯颗粒保温浆料外墙内保温施工技术是在“粉刷石膏聚苯颗粒保温砂浆”和“复合硅酸盐保温浆料”施工技术的基础上,吸收国外先进技术开发研制的。该技术解决了保温浆料
厨厕间装修的美观与否,直接影响着整个室内的观感。而厨厕间细部节点做法,也直接影响着厨厕间的装修效果。
文化人类学整体论是一个重要的学科范畴,其理论要旨在于强调事物的整体意识以及作为文化主体的人的意识,主要包括三方面的核心理念:其一,一种文化的整体特征并不等同于该文化整
发展大厦主楼23层、地下1层。工程场地地质条件:由上而下依次为:①杂填土,层厚1.00~3.00m,平均1.50m;②粉质粘土(或粘土),层厚1.80~5.10m,层面埋深1.00~3.00m;③淤泥或淤泥质土,层厚1.10~5
介绍了回采工作面针对不同来源的瓦斯所采取不同的抽采方法,以及本煤层、“随打即抽”、高位抽采及上隅角埋管抽采的各种技术参数,实践表明瓦斯分源抽采技术是一种较为有效的
昆大二期工程为框架剪力墙结构,建筑面积为16185m2,主楼地下1层、地上22层,总高83.1m。其基础为钻孔灌注桩,桩上为C30桩承台。rn 箱基底板和桩承台属大体积混凝土,混凝土浇筑施工