起重机是现代物料搬运的重要机械（machinery），实现了机械自动化，提高了劳动力，对我国工程(Engineering)建设的发展以及经济(Economy)的建设有很大的促进作用（role），起重机是现在使用(use)最广泛(extensive)的设备(shèbèi)之一。电动葫芦结构紧凑，电机轴线垂直于卷筒轴线的电动葫芦采用蜗轮传动装置。其缺点为：长度尺寸大，宽度方面尺寸大，结构粗笨，机械效率低，加工较难等。液压系统为双重控制，溢流调节阀、磁接点压力表均可对压力进行精确的控制。电器控制部门采用了低电压控制，增加了支配系统的安全性。电动葫芦是一种特种起重设备，安装在天车、龙门吊之上，电动葫芦具有体积小，自重轻，操作简单，使用方便等特点，用于工矿企业，仓储，码头等场所。起重机种类众多，常见的有港口起重机、单梁起重机、船用起重机等等，不管哪种起重设备(shèbèi)，都具有易损性、工作(job)繁重还有一定的危险(danger)性。
Crane is an important machinery for modern material handling. It realizes mechanical automation and improves labor force. It plays a great role in promoting the development of engineering and economic construction in China. Crane is one of the most widely used equipment (shbi). The electric hoist has compact structure, and the axis of the motor is perpendicular to the axis of the drum. Its shortcomings are: large length, large width, bulky structure, low mechanical efficiency, difficult processing and so on. Hydraulic system is double control. Overflow control valve and magnetic contact pressure gauge can accurately control pressure. Low voltage control is adopted in the electrical control section, which increases the security of the control system. Electric hoist is a kind of special lifting equipment, which is installed on crane and gantry crane. Electric hoist has the characteristics of small size, light weight, simple operation and convenient use. It is used in industrial and mining enterprises, warehouses, wharfs and other places. There are many kinds of cranes, such as port crane, single girder crane, marine crane, etc. No matter what kind of lifting equipment (shbi), it has vulnerability, heavy work and certain danger.