为了满足国民经济发展对小吨位汽车起重机的需要,武汉汽车起重机厂在华中工学院的协助下,设计、试制了QY3型三吨液压汽车式起重机。样机经过工业性考核,并由一机部长沙建筑机械研究所对整机性能、构件应力和液压系统参数进行了测定,达到设计要求,主要性能参数符合一机部部标JB1375-74的规定,于1978年通过鉴定。(见图1) In order to meet the needs of national economic development for small-tonnage truck cranes, Wuhan Automobile Crane Factory, with the assistance of Huazhong Institute of Technology, designed and prototyped the QY3 three-ton hydraulic truck crane. The prototype passed the industrial assessment, and the performance, component stress and hydraulic system parameters of the whole machine were measured by the Changsha Institute of Construction Machinery of a machine department, and the design requirements were met. The main performance parameters were in accordance with the requirements of a machine department department standard JB1375-74. Passed the identification in 1978. (see picture 1)