Bridge (gantry) crane: 2.2.1 Check that the wear of the brake pad pad should not exceed 50%, and the contact area between the pad and the brake wheel should not be less than 70%; Check the installation and fixing condition of each pin shaft, as well as its wear and lubrication. 2.2.2 Check all bolts for looseness and shortage. 2.2.3 Check the tightening of bolts on the bases of motors, reducers, etc., and tighten them one by one. 2.2.4 Check the lubrication condition of the reducer, the oil level should be within the specified range, and measures should be taken to prevent leakage in the oil seepage area. 2.2.5 Lubrication of gears. 2.2.6 Check the wear of the steel wire rope at the balance pulley and lubricate the pulley and pulley shaft. 2.2.7 Check the condition of the pulley to see if it is flexible, without any damage or cracks, and pay special attention to the wear of the fixed pulley shaft. 2.2.8 Check the brake wheel, and the unevenness of its working surface should not exceed 1.5mm. The brake wheel should not have cracks, and its radial circular runout should be less than 0.3mm. 2.2.9 Check the operation status of both large and small vehicles, and there should be no phenomenon such as gnawing on the track, three fulcrums, or twisting during starting and stopping. Check the wear of the wheel flange and tread. The wear of the wheel flange thickness should not exceed 50% of the original thickness, and the wear of the wheel tread should not exceed 3% of the original diameter of the wheel. 2.2.10 Check if the cable brackets, small pulleys, etc. are damaged or obstructed. 2.2.11 Keep the contactors, fuses, switches, etc. on the power box control screen clean to prevent leakage, breakdown, and short circuits from occurring. 2.2.12 Lubrication of various parts of the crane: Electric single beam (or half door) crane: 2.2.1 Check if all bolts are loose or lacking. 2.2.2 Check the operation status of both large and small vehicles, and there should be no phenomenon such as gnawing on the track, three fulcrums, or twisting during starting and stopping. Check the wear of the wheel flange and tread. The wear of the wheel flange thickness should not exceed 50% of the original thickness, and the wear of the wheel tread should not exceed 3% of the original diameter of the wheel. 2.2.3 Check the wear of the open gears of the large and small cars. 2.2.4 Check if the cable brackets, small pulleys, etc. are damaged or obstructed. 2.2.5 Check the wear of the electric hoist rope guide and adjust or replace it appropriately. 2.2.6 Ensure lubrication of all parts of the vehicle or use other highly corrosive lubricants. To ensure the safe operation of a single beam crane, it is necessary to be familiar with the causes of various crane malfunctions and the methods of troubleshooting. 1. To extend the service life of crane electrical equipment, it is necessary to regularly maintain the cleanliness of electrical equipment, such as resistors, control screens, contactors, etc. Remove internal and external dust, dirt, and attachments to prevent leakage, breakdown, short circuit, and other phenomena. 2. Regularly observe whether the contact of the motor rotor sliding wire and brush is poor, and whether there is wear and tear. 3. Is the sound emitted by the electric motor, brake, relay, etc. normal. 4. Check if there is any burning phenomenon on the cam controller and contactor contacts. If there is, replace it in a timely manner or use it after sanding it flat. 5