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| Faculty: | Mining Electrical Engineering and Automation |
| Speciality: | Power mechanical complexes of mining and coal-dressing aquipment. |
| Master: | Aushev N.A. |
| Leader of work: | Ustimenko T.A. |
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Analyzed a technological scheme in guiding of works in The Novotroitsk Mine Group based on drilling-and-blasting operations. Offered a new approach to mining based on a high-power hydraulic knocking mechanism which is capable to make a continuous, safe and planished process. Precipitant development of the open method of the design is called by its high productivity, profitability and safety as compared with the underground method. The Novotroitsk Mine Group is one of the mining and limestone conversion companies included The Limestoun Pit, The Crushing-And-Preparation Plant, three departments and series of sites providing a continuous work of the whole factory. The factory personnel is 860 workmen. The main machines which provide mining and transportation of minerals are: excavators ECG-5a, boring workbenches SBS-250MN, and automobiles Belaz with carrying capacity of 40 tones. The main production of the factory is the dolomotic limestone with which Novotroitsk Mine Group supplies the iron and steel industry, the ordinary limestone - chemical and food-processing industries, the building limestone - building companies and the agriculture. The limestone is mainly used for converter and ferroalloy production of steel, for blast-furnace process of cast-iron. In the food-processing industry the limestone is used for citric acid, bleaching of sugar. It is irreplaceable for production of carbide, carbonic gas, acetone. Wastage of breakstone (crushed rock) production give an opportunity to use it for production of breeze block, building block and other kinds of building production. This is why the main tasks of the factory is increase of productivity in mineral mining and labor safety. However, hard rocks and semi-hard rocks are characterized by power coefficient f = 6-7 by the prof. Protodyakonov scale which needs high energy for their breakdown. Nowadays drilling-and-blasting works are used for the mineral mining in conditions of the open pit. This method is widely the spread at the open-cast mining, it is characterized by impact of pressure appearing in result of inflammation of the explosive. For breakdown of the massif by the explosive method is blasthole drilling used with diameter 40-50 mm, with depth reaching 2 meters and well with diameter 100-105 mm and depth 40 meters. For drilling of blastholes and wells drilling machines are used (punchers, drills, installation and machines tools) which are complicated, expensive pneumatic or hydraulic machines. At drilling-and-blasting method this machinery is used periodically but needs constant care and keeping up of it in operable state. Conduction of drilling-and-blasting operations are accompanied by series of essential disadvantages:
water-drainage installations and water passages, placed on low horizons of pits: electric mains which supply mining equipment with energy get into a dangerous zone of demolition works; The above mentioned disadvantages of drilling-and blasting method are the reasons for search of new ways of mineral digging. One of such methods in conditions of the open pit is continuous mineral mining by means of mechanisms of impact action. Review of existing knocking mechanisms showed that there are knocking mechanisms ( hereinafter because of high energy parameters called RAMMERS) with an electrical, pneumatic and hydraulic drive gear. Electric rammers because of their low productivity have not found wide use. For pneumatic knocking mechanisms such properties: are mostly characteristic simplicity of the structure, reliability of work, capability to develop a high power at light weight. However, for breakdown of massifs of a mineral with strength more than 4 units by the prof. Protodyakonov scale pneumatic rammer must possess impact energy of level 500-1000 joules that will cause using of super-power compressors or compressor stations. Experience of building of hydraulic rammers confirms their obvious advantages over pneumatic ones:
1. Supply of high energy parameters; We think that development of complex which breaks minerals includes mechanical impact action onto working face, hydraulic impact action by means of a high energy flush is the actual task. In connection with this there is a significant problem in building a hydraulic rammer capable of running on the process water. Accessibility of this process water in conditions of the open pit makes hydraulic rammers of such kind attractive for using at the open mineral mining, for conduction of stripping and subsidiary works. Links: 1. Падуков Валентин Алексеевич и др. Разрушение горных пород при ударе и взрыве. Л., "Наука", Ленингр. отд-е, 1971. 161с. |