The composition of overhead crane
The bridge crane is the equipment that uses the hook (also use grab bucket or electric magnet chuck) to carry the material. The bridge crane is mainly composed of three parts: bridge structure, mechanical transmission and electrical equipment.
There shall be overload limiter and travel limiter switch for crane traveling mechanism and trolley traveling mechanism in accordance with the relevant regulations. And the lift height limiter switch, sweep the track plate and the supporting frame, conductive slip line protection board, ground, rail end safety protection device.
- When the load reaches 90% of the rated load, the system will send out an alarm signal; When the lifting load reaches the rated load, the system can automatically cut off the power supply and send out an alarm signal.
- It shall be able to cut off the lifting power automatically when it reaches the limit position.
- To prevent accidental touch between the spreader or the wire rope and busbar, a protective plate shall be set under the end beam which at the side of the busbar.
- A stop is set at the end of the track to prevent the bridge from derailment.
Safety precautions for mechanical part of overhead crane
- The parts of the overhead crane must be checked regularly to avoid the occurrence of uneven wear of pulley groove, which is easy to cause uneven contact with the steel wire rope pulley. Excessive wear of the pulley shaft will easily lead to the fracture of the pulley shaft. Once the wear exceeds the relevant provisions, it must be replaced.
- If the wear of the reel exceeds the standard or fatigue cracks appear, it is easy to cause damage to the roll; If the volume of the simple key wear is serious, easy to cause the key to fall off, cut off, serious easy to cause heavy falling. In this case it should be replaced
- The small shaft of the brake, spindle, brake wheel, brake shoe pad wear out of specification and fatigue cracks in the tie rod and spring are easy to cause brake failure, should be replaced.
- If the dangerous inspection section at the opening of the hook has excessive wear or fatigue cracks appear on the end, the end thread retracting groove or the surface of the hook, it is easy to cause the hook to break. Therefore, hook loading should be checked 1 to 3 times a year, found that timely replacement
- If the wheel spokes of the crane wheel, tread fatigue cracks, or wheel rim, tread wear exceeds the standard, are easy to cause wheel damage, serious cause derailment of the crane.
- If the trolley is stopped on the track, the motor starts too hard and the wheel pressure is not even, it is easy to cause the trolley's running mechanism to slip; It is easy for a small wheel to be subjected to even force due to deviation of the trolley, unequal diameter of the wheels, excessive wheel installation error, deformation in the process of making the trolley body and uneven wheel pressure. Therefore, it must be adjusted.
- Regularly check the temperature, sound and lubrication of the bearings of the crane; If the sound of the reducer is abnormal, it should be repaired or replaced in time.
- If the deviation of the transmission system is too large, the deflection of the frame, the installation error of track and wheel is too large, and the oil is stored on the track, it is easy to cause the crane to run and gnaw, so it must be adjusted, cleaned and corrected in time.