四川化工厂增建一套从国外引进的先进术技装置——年产合成氨三十万吨,年产尿素四十八万吨和相应辅助工程的单系列化肥装置。为了完成大型设备的吊装任务,我们在二十多个兄弟单位和贫下中农大力协作下,将原有一台起重能力为40吨的五十年代的塔式起重机,采取“一用、二批、三改、四创”的办法改装成为起重能力达到400吨的塔桅起重机。 The Sichuan Chemical Plant has added a set of advanced technical equipment imported from abroad—a single-series fertilizer plant that annually produces 300,000 tons of synthetic ammonia, 480,000 tons of urea, and corresponding auxiliary projects. In order to complete the hoisting tasks of large-scale equipment, we cooperated with more than 20 fraternal units and underprivileged middle farmers to take the original tower crane with a capacity of 40 tons in the 1950s and adopted “one-use, two-batch, The three-reform and four-innovation methods were converted into tower cranes with a lifting capacity of 400 tons.