How the safety devices of gantry crane works?
Safety devices of gantry crane make gantry crane work well. They can raise the alarm and index signal to quickly deal with the breakdown and dangerous situation in order to avoid accidents, maintain normal protection and protect life safety of employees. So, it is necessary to design and install safety devices.
1. Ascending limiting position limiter
As starting lifting mechanism, the spreader works in the range of operational height
2. Moving limiting position limiter
When the trolley/ crane travelling mechanism moves to limit position, stop it to ensure the crane to work in the service area
3. Deviating adjustment device
When travelling mechanism of gantry crane and loading bridge works, support legs running speed at two ends of main girder usually is different due to many factors such as different running resistance, wheel-slip, difference of diameter of wheels, efficiency of transmission system, tiny difference of motor sliding rate between drive systems at two ends and installation deviation of travelling mechanism. Above differences will cause the damage of crane metal structure and cause severe wear; to make matters worse, it will do harm to travelling mechanism and cause accidents. Deviating adjustment device can avoid or reduce such bad situation.
4. Buffer
Absorb kinetic energy produced when the crane crash with terminal baffle or crane
5. Wind resistance and anti-creep device
Mainly includes:
Rail clamping device, anchoring device and cast brake shoe
5.1 rail clamping device
The jaw clamps the rail to stop crane slipping to realize wind resistance. To keep a reliable function of wind resistance for rail clamping device, the jaw must have enough clamp force
5.2 wind resistance cast brake shoe
There are two control modes: manual control and electric control
5.3 anchoring device
Chain wind resistance anchoring device and latch plate wind resistance anchoring device
6. Lifting capacity limiter
Stop crane from overloading. When overloading happens, it can stop crane moving to unsafe area and allow crane to move to safe field with sound and light alarm signal
7. Over speed switch
Limit the max speed of the motor and rapidly turn off circuit to ensure a safe operation.