毕业设计方案,外文翻译,起重机.docVIP

二 ○ 一 三 届毕业设计 外文翻译 学 院： 工程机械学院 专 业： 机械设计制造及其自动化 姓 名： 赵国超 学 号： 2504090516 指导教师： 陈新轩 完成时间： 2013 年 3 月 27 日 Type of Cranes 起重机的类型 Cranes can be classified into four kinds, namely, (a) overhead traveling crane; (b) jib crane; (c) bridge or gantry crane; and (d) cantilever crane. 起重机可分为四类：高架移动起重机、动臂起重机、桥式或门式起重机、悬臂吊车。 Overhead traveling crane. Consists of a girder and a trolley. The girder is supported at each end on trucks capable of traveling on elevated fixed tracks. The trolley is equipped with hoisting and other mechanism, capable of traversing from end to end of such girder. The girder and associated end carriages are known as the bridge. 高架移动起重机由横梁和空中吊运装置组成。横梁靠固定道轨支承，并且可以在轨上来回移动。空中吊运装置由提升装置和其他装置组成，可以从横梁的一端运动到另一端。横梁和与之相连的框架统称为桥。 Such cranes vary in lifting capacity from about 2 tons to 400 tons, and in span from 20 ft to 150 ft,or more. Depending on the purpose for which it is to be used, the crane can be operated either from a cabin fixed to the bridge or the trolley, or from the ground. When two trolleys are furnished, these may run on a common tracks arranged side-by-side or one above the other so that each trolley can traverse the entire span. 这些的起重机囊括了起重量从2吨到400吨，跨度从20英尺到150英尺的各种类型。根据目的,在机舱起重机在桥或,其他情况控制装置常在地面。移动和履带起重机,建筑商,码头起重机、塔式起重机和可移动的安装在高台子,井架,浮筒和驳船起重机。起重能力不同1/2吨到300吨,动臂可伸展范围从几英尺到150英尺。需要在船厂、港口处理重型机械和设备起重机经常安装在驳船。 舾装o且可以在平面内转动的悬臂。然而，它有一个重大的缺点：当悬臂水平转动时，悬挂在悬臂上的货物会随之缓慢提升。只有，当吊杆位于较低位置时，货物提升相同的高度。显然，这意味着能量的损失和一个本不需要的用于驱动摆动装置的大功率马达。 To overcome this objection a number of different designs of a type of crane known as the level-luffing crane have been developed, and these cranes are now extensively used as wharf cranes. In this type of cranes a compensating gear in some form or another is provided whereby the load is made to travel along a horizontal path irrespective of the rise and fall of the hoisting pulley caused by the luffing-in or out of the boom. 为了弥补这一缺陷，一类有着独特设计的起重机迅