采用焊接法维修拖拉机铸铁件时,除根据实际情况选择适宜的焊接方法外,还应注意以下几点事项: 一、焊前准备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、油漆等彻底清除干净;焊补裂纹时若焊件壁厚小于25毫米,则应钻出直径4毫米左右的止裂孔;有的焊件还要根据壁厚和工艺的要求选择坡口型式等。 The use of welding repair tractor cast iron parts, in addition to the actual selection of the appropriate welding methods, should also pay attention to the following points: First, the preparation before welding Welding parts should be welded and all the surrounding impurities such as rust , Oil, paint and other clean thoroughly; weld crack if the welding wall thickness less than 25 mm, you should drill a diameter of about 4 mm crack hole; some weldment but also according to wall thickness and process requirements choose bevel Type and so on.