外文翻译-提升系统.docVIP

毕业设计 外文文献翻译 专业：机械设计制造及其自动化 班级：机设0808班 姓名：李万平 学号：0805040810 指导老师：何万库 时间：2012年6月1日 Chapter 17.5 HOISTING SYSTEMS FRED A. EDWARDS 17.5.1 INTRODUCTION After a detailed technical feasibility study has indicated the commercial viability of exploiting an ore body using underground methods, an adequate planning and design process for mine access should begin. Two general types of access should be considered: (1) vertical to near-vertical shafts using hoists and cable-suspended conveyances, or (2) horizontal or inclined openings using rail, trucks, conveyors, or cable-operated conveyances. Because a shaft often provides the most direct access over the longest period of time, there is an advantage to designing a shaft for maximum duty, consistent with economy. The current trend in shaft design is to provide multipurpose shafts. These shafts contain facilities for handling ore, waste, materials, personnel, services, man ways, and ventilation. During the process of identifying the purpose of the shaft, it should be realized that once a shaft is excavated and equipped, it cannot be enlarged easily in the future. Therefore, the shaft’s initial and ultimate requirements must be defined during the design phase. This chapter presents the information and criteria necessary to design or select a mine shaft hoisting system. Specific topics such as hoist selection, hoist rope details, head frame design, shaft furnishings and equipment, as well as shaft lining design, are included in the discussion. Ramps and tunnels are dealt with in a similar fashion in Chapters 17.4 and 24.1. A system is defined as a group of units so combined as to form a whole and to operate in unison. Thus, when designing a shaft hoisting system, one must consider not only each part of the system separately but the interrelationships among the parts of the system in its entirety. For the purpose of this discussion, the shaft hoisting system has been divided into five main components: (1) hoist, (2) conveyance, (3)