1. Measures to prevent hook slipping during parking braking
(1) Adjust the brake clearance regularly and evenly according to the technical requirements of the brake product manual of gantry crane.
(2) Regularly lubricate the movable joint with lubricating oil to keep the action of the movable joint flexible.
(3) Adjust the main spring tightness, brake clearance and push rod stroke regularly according to the product manual.
(4) Replace the brake wheel in time.
2. Measures to prevent hook slipping during braking
(1) Regularly check and maintain the electrical control system to ensure the reliability of power supply; Ensure that the internal voltage drop of gantry crane does not exceed 5%.
(2) Adjust the control program of the electrical control system to reduce the speed of the motor to the set speed of soft braking. After the system sends the brake closing command, the speed regulating device continues to keep the motor with a certain electromagnetic torque until the brake braking process is completely completed. This setting can not only realize the soft parking function of the lifting mechanism of the gantry crane, but also ensure the accurate parking of the lifting mechanism.
(3) Adopt closed-loop control, redundancy design and anti-interference technology to improve the reliability of the electrical system control of gantry crane and reduce the failure rate of the system. Add emergency control procedures, that is, in case of accidental hook slipping, immediately start the emergency stop function. For occasions with high safety requirements, a set of safety brakes should be added. Carry out system maintenance regularly to reduce the failure of system control components due to environmental factors.
3. Measures to prevent hook slipping during lifting and lowering operations
(1) Regularly check and maintain the electrical control system to ensure the reliability of power supply; Ensure that the internal voltage drop of gantry crane does not exceed 5%.
(2) Adjust the control program of the electrical control system, add sequence control, and detect the starting torque value of the motor. When the starting torque of the motor is greater than or equal to the sum of the static torque of the lifting goods and the friction torque of the transmission mechanism, give the command to open the brake.
(3) Adopt closed-loop control, redundancy design and anti-interference technology to improve the reliability of the electrical system control of gantry crane and reduce the failure rate of the system. Add emergency control procedures, that is, in case of accidental hook slipping, immediately start the emergency stop function. For occasions with high safety requirements, a set of safety brakes should be added. Carry out system maintenance regularly to reduce the failure of system control components due to environmental factors.
4. Measures to prevent hook slipping caused by illegal operation
In order to prevent hook sliding failure caused by illegal operation of gantry crane, the interlock control of overload protector and gale alarm on the operation circuit should be improved to prevent overload operation. In case of accidental hook slipping fault, it is forbidden to deal with the hook slipping fault by reverse operation. The emergency stop button should be operated in time, the power supply should be cut off, and the forced shutdown should be carried out to prevent the expansion of the fault. Operators should be regularly trained in safe operation to develop good operating habits and prevent misoperation.
