前言近十几年来,国内外对梁式起重机的总体布置方案和金属结构形式进行了一系列的研究和改进,出现了一些性能好,自重轻,运输方便和制造成本低的结构形式,从有关的报导不难看出,他们主要是通过采用更为有利的结构形式和采用轻金属材料两个途径以减少材料耗用量和降低制造成本的。就我国当前的情况而言,首先值得注意的似乎是采用更为合理的结构形式。 Preface In the recent ten years, a series of researches and improvements have been made on the overall arrangement of beam cranes and metal structures at home and abroad, and some structural forms have emerged that have good performance, light weight, convenient transportation and low manufacturing cost. It is not hard to see that they mainly reduce material consumption and manufacturing costs by adopting more advantageous structural forms and adopting light metal materials. As far as the current situation in our country is concerned, it seems worth noting, at first, that it adopts a more rational structure.