《外文翻译模版.doc

毕业论文（设计） 外文翻译 题 目： 输送机系统 系部名称： 系 专业班级： 学生姓名： 学 号： 指导教师： 教师职称： 2014年月日 CONVEYOR SYSTEMS Conveyors are used when material must be moved in relatively large quantities between specific locations over affixed path. The fixed path is implemented by a track system, which may be in-the-floor, above-the-floor, or overhead. Conveyors divide into two basic categories: (1) powered and (2) no-powered. In powered conveyors, the power mechanism is contained in the fixed path, using chains, belts, rotating rolls, or other devices to propel loads along the path. Powered conveyors are commonly used in automated material transport systems in manufacturing plants, warehouses, and distribution centers. In non-powered conveyors, materials are moved either manually by human workers who push the loads along the fixed path or by gravity from one elevation to a lower elevation.  Types of Conveyors  A variety of conveyor equipment is commercially available. In the following paragraphs, we describe the major types of powered conveyors, organized according to the type of mechanical power provided in the fixed path.  Roller and Skate Wheel Conveyors. These conveyors have rolls or wheels on which the loads ride. Loads must possess a flat bottom surface of sufficient area to span several adjacent rollers. Pallets, tote pans, or cartons serve this purpose well. The two main entries in this category are roller conveyors and skate wheel conveyors, pictured in Figure 10.6.  In roller conveyors, the pathway consists of a series of tubes (rollers) that are perpendicular to the direction of travel. The rollers are contained in a fixed frame that elevates the pathway above floor level from several inches to several feet. Flat pallets or tote pans carrying unit loads are moved forward as the rollers rotate. Roller conveyors can either be powered or non-powered. Powered roll