When determining the crane needs overhaul , we should pay attention to exclude security risks. Overhaul process should be taken to exclude security risks , such as: adjust the gap brakes , replace worn 2 ton Electric Chain Hoist clutch friction plate and make the cab seat can be easily adjusted up or down , and the removal of some of the drivers and maintenance personnel likely to cause injury and machine malfunction security risks. When strengthen labor protection awareness of the driver , making the machine dangerous experiments , sufficient space should be left around and protective facilities. Secondly , good tracking service overhauled . Build construction machinery overhaul maintenance files and repair the unit should be within a certain period after repair works to ensure that the mechanical energy to achieve the specified performance and good condition . If a fault occurs generally within this period , after adjustment to exclude those who can , should use the units themselves. Because such a large change. Mechanical damage , severe oil spills, leaks , leaks and leakage and other major components must be disassembled for repair , the unit should be serviced by a joint notice to repair the unit checks timely repair to reduce downtime , so after overhaul the machine can be kept in good working condition.