采用焊接法维修农机铸铁件时,除根据实际情况选择适宜的焊接方法外,还应注意以下事项。(1)焊前准备。农机件焊接前应将焊件焊接部位及其周围的一切有害杂质如铁锈、油污及油漆等彻底清除干净。焊补裂纹时,若焊件壁厚小于25mm,则应钻出直径4mm左右的止裂孔。有的焊件还要根据壁厚和工艺要求首先制出焊接坡口等。(2)焊条及其直径的选择。不同类型的铸铁件应选用与其对应的焊条。 When using the welding method to repair agricultural cast iron parts, in addition to select the appropriate welding method according to the actual situation, we should also pay attention to the following matters. (1) Preparation before welding. Agricultural machinery parts should be welded before welding parts and all the surrounding impurities such as rust, oil and paint thoroughly removed. Welding cracks, if the weldment wall thickness is less than 25mm, you should drill a hole diameter of about 4mm crack. Some weldment but also according to the wall thickness and process requirements first made welding groove. (2) electrode and its diameter selection. Different types of cast iron should be used with the corresponding electrode.