我局很多进口工程机械经长期运转，一些铸铁基础件（如三菱罐车发动机缸体、日立40t履带起重机液压马达壳体和依维柯自卸汽车变速箱壳体等）产生裂纹。由于机型较老、基础件价格昂贵且很难买到，为保证工程机械的正常运行，对这些零件必须进行修复。一、铸铁壳体裂纹的焊修特点 A lot of imports of construction machinery by the Bureau of long-term operation, some of the basic parts of cast iron (such as Mitsubishi tanker engine block, Hitachi 40t crawler crane hydraulic motor housing and Iveco dump truck gearbox, etc.) crack. Due to the older models, the basic parts are expensive and difficult to buy, these parts must be repaired in order to ensure the normal operation of the construction machinery. First, the cast iron shell crack repair characteristics