北京六建工人和北京建筑工程研究所共同研制的向阳4号起重机(见工程机械1974年第4期),具有重量轻、结构简单、易于制造、操作平稳和移动方便等优点。为提高我站施工机械化水平,我们学习首都工人阶级大搞技术革 The Xiangyang No. 4 crane jointly developed by Beijing Liujian Workers and the Beijing Institute of Architectural Engineering (see Engineering Machinery No. 4 in 1974) has the advantages of light weight, simple structure, easy manufacturing, stable operation, and easy movement. In order to improve the level of construction mechanization at our station, we learned that the working class in the capital has engaged in technological upgrading.