Question

本人英语实在太差，哪位高手帮忙翻译一下万分感谢，一定要通顺。多谢各位朋友了。

起重机的概念和发展史
在一定范围内垂直提升和水平搬运重物的多动作起重机械。又称吊车。属于物料搬运机械。起重机的工作特点是做间歇性运动，即在一个工作循环中取料、运移、卸载等动作的相应机构是交替工作的。
中国古代灌溉农田用的桔?是臂架型起重机的雏形。14世纪，西欧出现了人力和畜力驱动的转动臂架型起重机。19世纪前期，出现了桥式起重机；起重机的重要磨损件如轴、齿轮和吊具等开始采用金属材料制造，并开始采用水力驱动。19世纪后期，蒸汽驱动的起重机逐渐取代了水力驱动的起重机。20世纪20年代开始，由于电气工业和内燃机工业迅速发展，以电动机或内燃机为动力装置的各种起重机基本形成。
起重机主要包括起升机构、运行机构、变幅机构、回转机构和金属结构等。起升机构是起重机的基本工作机构，它们大多是由吊挂系统和绞车组成，也有通过液压系统升降重物的。运行机构用以纵向水平运移重物或调整起重机的工作位置，一般是由电动机、减速器、制动器和车轮组成。变幅机构只配备在臂架型起重机上，臂架仰起时幅度减小，俯下时幅度增大，分平衡变幅和非平衡变幅两种。回转机构用以使臂架回转，是由驱动装置和回转支承装置组成。金属结构是起重机的骨架，主要承载件如桥架、臂架和门架可为箱形结构或桁架结构，也可为腹板结构，有的可用型钢作为支承梁。
起重机根据结构的不同可以分为：①桥架型起重机。可在长方形场地及其上空作业，多用于车间、仓库、露天堆场等处的物品装卸，有梁式起重机、桥式起重机、龙门起重机、缆索起重机、运载桥等。②臂架型起重机。可在圆形场地及其上空作业，多用于露天装卸及安装等工作，有门座起重机、浮游起重机、桅杆起重机、壁行起重机和甲板起重机等。另外，起重机也可以根据驱动方式、工作类型、机动性和用途等进行分类。

Answer 1

The concept and the development history of the derrick
Perpendicular in the certain scope promote with the level porterage heavy thing much action derrick 械 .Call hoist again.Belong to the material porterage machine.The work of the derrick the characteristics is to do by fits and starts sport, taking to anticipate in a work the circulation,the luck move,unload etc. action of correspond organization is alternation work of.
China ancient times irrigation 桔 used in farmland?BE the arm type the embryo of the derrick.14 century, the Western Europe appear the manpower and the 畜 dint to drive of turn and move the arm type derrick.Period 19 centuries ago, appear a bridge type derrick;Derrick of the importance wear away a piece,such as stalk,wheel gear, and mourn etc. a beginning adoption the metals material manufacturing, and beginning adoption the water power drive.19 period after century, the steam drive of derrick gradual replace water power drive of derrick.20 century 20's beginning, because of electricity industry and I.C. engine industry quick development, take the electric motor or the I.C. engine as motive equip of various derrick is basic formation.
The derrick is main to include to rise organization,circulate organization,become an organization and turn round the organization and metals structure etc..Rise organization is the basic work organization of the derrick, they mostly from hang to hang the system and winch to constitute, have already pressed system to ascend and descend a heavy thing through a liquid as well.Work circulated organization in order to and lengthways the level luck to move a heavy thing or adjust derrick position, general from electric motor,decelerate machine,make to move the machine and car wheel to constitute.Become an organization an equipment a type a derrick at the arm up, the arm 仰 the hour range let up, the 俯 descend the range enlarge, cent the balance change and not the balance change two.Turn round organization to make in order to the arm turn round, from drive equip and turn round to accept equip to constitute.The metals structure is the framework of the derrick, the main loading piece,such as the bridge,the arm and door, can is box the form structure or the 桁 structure, can also for the stomach plank structure, have of can use a steel as to accept beam.
The derrick can is divided into according to the dissimilarity of the structure:The ① bridge type derrick.Can at the rectangular place and its sky homework, used for car more,the warehouse,open-air heap field the product of[with] etc. pack to unload, having a beam type derrick,bridge type derrick,Dragon gate derrick,cable 索 derrick,carry bridge...etc..The ② arm type derrick.Can in the circular place and its sky homework, much used for open-air pack to unload and install etc. work, have a derrick and float to swim a derrick,mast derrick,wall a line derrick and the deck derrick etc.s.Moreover, derrick can also according to drive way,the work type,flexibility and use etc.s to carry on a classification.

Answer 2

一句两句还可以，这么多，累傻小子呢吗？楼主真会利用免费平台。并且悬赏分居然是0~~~

Answer 3

Crane and the history of the development of the concept
At a certain scope and level of vertical lifting many of the action to carry a heavy load lifting equipment. Also known as the cable car. Belong to material handling machinery. Crane's work is characterized by intermittent exercise to do, that is, a job at reclaiming cycle, transport, unloading, etc. The corresponding action is the turn of the job.
Ancient Chinese irrigation used orange? Is the embryonic form of boom-type cranes. The 14th century, Western Europe appeared in human and animal-driven boom-type crane rotation. The early 19th century, a bridge crane; cranes wear items such as essential axis, gear and began to use metals such as spreader materials, and introducing the hydraulic drive. The late 19th century, steam-driven crane gradually replaced the hydraulic-powered crane. The beginning of the 20th century's 20, because of the electrical industry and the rapid development of industrial internal combustion engine, electric motor or internal combustion engine to power devices for a variety of crane is basically formed.
Crane main lifting mechanism, operating agencies, luffing mechanism, slewing mechanism and metal structure. Crane hoisting mechanism is the basic job agencies, they are hanging from the winch system and components, but also through the hydraulic system of lifting heavy objects. Vertical run to the level of migration body weight or adjust the location of cranes, is normally provided by electric motors, reducers, brakes and wheel components. At only equipped with luffing jib type crane, the arm looked up and when the rate of decrease, the rate increased when leaned over, sub-balance variation and variation in two non-equilibrium. Slewing mechanism to enable the rotary arm is driven slewing devices and device components. Metal structure of the skeleton is a crane, main bearing parts such as bridge, jib and gantry for the box structure or truss structure, but also for the web structure, and some can be used as the supporting steel beams.
According to the structure of different crane can be divided into: ① bridge-type cranes. Venues in rectangle and over homework, for the many workshops, warehouses, open storage space for loading and unloading of goods, etc., there is beam cranes, bridge cranes, gantry cranes, cable cranes, carrying bridges. ② jib cranes. In the circular space over the homework and are used for loading and unloading and installation of outdoor work, have portal cranes, floating cranes, mast crane, wall lines, such as cranes and deck cranes. In addition, the crane can also drive the types of work, mobility and use of the classification.