1. Technical preparation before maintenance of bridge crane.

In the maintenance work of bridge crane, it is important to establish normal maintenance order, improve the quality of maintenance and shorten the maintenance work stoppage, especially for equipment overhaul.

Bridge crane equipment in the process of maintenance, maintenance as far as possible to rest days, and to ensure that the repaired equipment meet the technical conditions, must be before the repair and maintenance technology in the process of preparation work well. Equipment maintenance technical preparation procedure.

2. Breakdown maintenance of crane mechanical system.

1. Analysis of common fault causes of cranes.

1) crane mismanagement, drivers or manipulate staff strict examination system, equipment "to perform his duties" no strict operational procedures, improper safekeeping, not properly sealed and unsealed, no vehicle technology archives, etc., can make the crane malfunction.

Use and maintain bad storage. If use improper, overloading, slanting, the ground is uneven, do not hit the leg and so on will cause the crane to overturn; Such as poor maintenance, no loose connection, pipe burst, oil leakage, pressure is not enough, luffing line tripping, jib pin shaft cut, etc., cause the operation of the crane jib break, etc.

The operation is illegal. Do not follow the crane operation procedures, not the driver, misoperation, do not understand crane structure, performance, characteristics, blind operation, etc., will bring disaster.

Design quality, part life. After the use of the crane for a period of time, the constant fatigue and wear is the most fault factor. This mainly depends on the life span of the parts, and the reason for the failure is the unreasonable design, poor quality and lax inspection.

2. Judgment of common faults of cranes.

According to crane spare parts usage and harm degree of safety, often combined with the maintenance work on the inspection, at the same time need to be able to judge, to hidden trouble, eliminate the fault, nip in the bud. Of course, it takes a lot of experience to work, but experience builds slowly.

A flaw detector. It has great impact on safety, and it is difficult to detect defects in human eyes. For the check of hook hook, hook neck and pin shaft, check the shaft neck crack of the coupling, the axle neck crack of gear reducer and the spool spindle.

With the sound. For example, the "rumble" sound when the boom is falling and turning, indicates that the gap between the brake belt and the brake wheel is too small and the spring pressure is not moderate; If the gear transmission has noise, the lubrication is insufficient, gear wear, meshing is bad, etc. If the gearbox makes a jolt, it indicates that the tooth side clearance exceeds the standard; If the bearing rings, the bearing assembly is poor and the bearing is stuck; If the hydraulic pump has noise, the fixing bolt is loose or the sealing element is damaged; If there is noise in the oil pump, the oil pump has air entry and the oil level is too low. If there is a sharp metal rasping in the gearbox, it is indicated that the transmission gear is too small.

The sense of smell. If the oil is smelly, the oil has gone bad; The brake lining has the coke smell, indicating that the brake wheel and the brake band gap are too hot; If the wire is burnt, the line is burnt, etc.

It depends on touch. If the bearing of the reducer is pressed with the back of the hand, it indicates that the bearing is less oil or too much oil, such as the hand touching the brake wheel, which indicates the friction between the brake wheel and the liner. Generally when the environment temperature is 25 ℃, bearing, brake drum temperature should not exceed 60 ~ 70 ℃.

It's a vision. If the damage of the parts is observed, the crack, bending deformation, instrument failure, whether the steel wire rope has broken stock, broken wire or wear condition, brake failure and the hook have large deformation, etc.