What Electrical Safety Devices Are Installed On Cranes? 1
Nov 18, 2023
What electrical safety devices are installed on overhead cranes? What role does each play? -- first part
What electrical safety devices are installed on the gantry cranes? What role do each play? - the second part
What electrical safety devices are installed on the bridge cranes? What role do each play? - Part 3
1. Overload limiter
Function: The comprehensive error of the overload limiter should not be greater than 8%. When the load reaches 90% of the rated load, an alarm signal should be issued. When the lifting weight exceeds the rated lifting weight, the lifting power source can be automatically cut off and a prohibitive alarm signal will be issued.
Should be installed: 10 ton bridge cranes with a rated lifting capacity greater than 20t, gantry cranes with a rated lifting capacity greater than a lot, railway cranes, and 10 ton overhead gantry cranes.
Suitable for installation: 10 ton overhead bridge cranes with a rated lifting capacity of 3-20t, 10 ton gantry cranes with a rated lifting capacity of 5-10t, and tower cranes with a lifting moment less than 25t.
2. Torque limiter
Function: The comprehensive error of the torque limiter should not be greater than 10%. When the load moment reaches the rated lifting moment, the power source for lifting or luffing can be automatically cut off and a prohibitive alarm signal is issued.
Should be installed: truck cranes, tire cranes, and crawler cranes with a lifting capacity equal to or greater than 16t, tower cranes with a lifting capacity equal to or greater than 25t.
Suitable for installation: truck cranes, tire cranes, and railway cranes with a lifting capacity of less than 16t.
3. Ascent limit position limiter
Function: It must be ensured that when the spreader reaches the limit position, the power source of the lifting is automatically cut off.
Should be installed on: all types of cranes.
4. Descending limit position limiter
Function: Under working conditions where the spreader may be lower than the lower limit position, it should be ensured that when the spreader drops to the lower limit position, the power source of the descent can be automatically cut off to ensure that the winding of the wire rope on the drum is not less than that specified in the design. A number of turns.
Should be installed: 10 ton bridge overhead crane, tower crane, and gantry crane as needed.
5. Operating limit position limiter
Function: It should ensure that when the mechanism reaches the extreme position, it will automatically cut off the forward power source and stop the movement.
It should be installed on: trolleys and trolleys of 10 ton bridge cranes and 10 ton gantry cranes, and the boom of the gantry crane is at the extreme position of operation.
6. Deflection adjustment and display device
Function: When the outriggers at both ends are deflected due to different forward speeds, the deflection can be indicated to the driver so that the deflection can be adjusted.
Suitable for installation: 10 ton gantry cranes with a span equal to or greater than 40m.
7. Amplitude indicator
Function: It should be ensured that the crane with the luffing mechanism can correctly indicate the amplitude of the spreader.
Should be installed on: truck cranes, tire cranes, crawler cranes, railway cranes, tower cranes, and portal cranes.
8. Interlock protection device
Function: Between the support stopper of the boom and the luffing mechanism of the boom, the luffing mechanism cannot start before the stopper removes its supporting function.
Should be installed: Tower crane.
Function: The door to enter the bridge crane and gantry crane and the hatch door from the driver's cab to the bridge. When the door is opened, the operating mechanism of the crane cannot be started. When the driver's cab is located in the moving part, the operating mechanism cannot be started when the door to the passageway into the driver's cab is opened.
Should be installed: 10 ton overhead crane.
