1、翻译部分英文原文Shearer mining application to soft thin-seam with hard roofZhai Xin-xiana,b,*, Shao Qianga, Li Bao-fua, Li Xiao-junaaSchool of Energy Science and Engineering, Henan Polytechnic University, Jaozuo 454000, China;bSchool of Civil and Hydraulic Engineering, Dalian University of Technology, Dalia
2、n 116023, ChinaAbstract Study status on shearer mining in thin seams in the world is introduced. Base on the geological conditions of instable and soft thin-seam with hard roof in Caoyao Coal Mine of Yima Coal Group, China, and combined with related parameters of strata behaviors at coal faces, the
3、concludes that the strata control on the thin-seam coal face is comparatively easy in line with the criteria for classification on strata stability of gently-inclined coal faces in China. Hydraulic supports of two-prop shielding with rated effective resistance of 2400kN can be employed in thin seam
4、coal faces. Basic requirements for coordination equipments of shearer are summed up while mining thin seams. According to successful experiences of extracting thin seams in similar geological conditions in China, the scheme of feasibility coordination equipments of shearer is optimized in thin seams
5、 with thickness of 0.8-1.4m and 1.1-1.9m, respectively. The conclusions will provide a reference value for Caoyao Coal Mine on carrying out mechanized mining of the mine, improving safety production capability, and prolonging the mine life.Keywords: thin seam; shearer mining; equipment coordination;
6、 hard roof; soft coal1. Mining status with shearer in thin seams As to the selection of mining equipments, coal mining technology in medium-thick seams is similar to that in thin seams, the United States of America and other western countries call coal seams with the thickness less than 2.0m as the
7、thin seams in line with practicability. Therefore, international definition is used to construct mines with safety and high efficiency, coal seams with thickness of 0.8-2.0m are also named as the thin ones. At present, both longwall mining home and abroad for thin seams has two technological methods
8、: one is the fully mechanized mining equipped with shearer, scraper conveyer and hydraulic supports; the other is the fully mechanized mining using plow, scraper conveyer ( or running track) and hydraulic supports. Coal mining method with spiral drill has been widely applied in thin seams in Ukraine
9、 and China 1, 2, and the latter represents Xinwen mining area. Longwall mining by shearers and room-and-pillar mining with continuous miners have been implemented in thin seams in the United States of America and United Kingdom; while unmanned automatic mining has been carried out in thin seam coal
10、faces with plows and hydraulic supports by electro-hydraulic control in Germany. From the conditions of their service, both shearers and plows have achieved better economic results, but each mining machine has a certain advantages and dis advantages to adapt to different geological conditions. Outpu
11、t in fully mechanized longwall coal faces in the United States of America has been in a leading position in the world, while annual output of 2.86Mt at coal faces of thin seam with thickness of 1.3- 2.0m has been achieved, the efficiency of 411t per miners at coal faces has also been achieved. From
12、2004 to 2005, the United States of America had 52 longwall faces, in which 21 coal mines of thin seams with thickness were less than 2m (only one coal face with plow and 20 coal faces with shearers). Annual output of coal face with plow was 15.9 million tons, while work efficiency of coal face was 1
13、817 tons per miner. While annual output at coal face of shearer was 15.9-92.7 million tons, average annual output was 44.87 million tons, the average work efficiency was 3513 tons per miner 3, 4. It showed that good economic and technical effects could be obtained with high-power winning equipments
14、in thin seams with small thickness. Presently, there are two kinds of shearers in thin seams in China, i.e., ones which are imported and made in China. The latter of the series of MG shearer-loader are main models 5. In 2006, on the geological conditions of thin seam whose dip angle is 3-6, average
15、thickness is 1.35m, and Protodyakonov coefficient is f = 1.6, Binhu Coal Mine in Zaozhuang City employed the following coordinating equipments: MG340-BWD1 shearer, ZY2400/0.9/2.0 hydraulic support and SGZ-730/320 scraper conveyor. With above coordinating equipments, the average yield of coal face wa
16、s 80 thousand tons per month and the maximum yield was 3504 tons per day. Under the coal seam conditions of average thickness of 1.3m, both Daizhuang Coal Mine in Zibo City and Tongjialiang Coal Mine in Datong City achieved average yield of 6.8-8.0 million tons per month at coal face by Chinese shearer of MG series, the hydraulic supports with two-prop shielding and associated equipments. Shearers have a strong adaptability to geological conditions; it i
