In the gantry crane system, the selection and layout of cables are crucial and directly related to the safety, stability and service life of the equipment operation.
1. Application requirements
When the gantry crane is powered by a cable drum, it should be ensured that the cable can be automatically and smoothly retracted and released. The specific requirements are as follows:
- Driving torque: The driving torque of the cable reel should not be less than the maximum winding torque required for winding the cable to ensure normal operation under different load conditions.
- Traction force control: During the cable release process, the traction force applied to the cable conductor should be reduced as much as possible. For cables without a reinforced core structure, the maximum allowable tensile force on the copper conductor shall not exceed 20N/mm².
- Strengthened structure: For applications with heavy weight or high operating speed, cables with steel wire rope reinforcement should be selected to withstand greater traction.
2.Layout principles
When laying out cables, mechanical stress distribution, space utilization, and convenience for later maintenance should be taken into consideration:
- Length and outer diameter consistency: All cables should be of the same length, similar outer diameter, and firmly crimped to avoid excessive stress on individual cables.
- Uniform distribution: Cables laid on the same layer should be as close in size as possible to avoid local concentrated force and affect life.
- Traction wire rope: If a suspended cable trolley is used, a traction wire rope should be set to balance the tension. When the angle between two adjacent trolleys is close to 120°, the traction wire rope should be fully straightened and withstand the traction force.
3. Size requirements
To reduce the bending stress during cable winding, the bottom diameter of the reel should be designed reasonably:
- Cable with outer diameter ≤ 21.5mm: The bottom diameter of the reel should not be less than 10 times the outer diameter of the cable.
- Cable with outer diameter > 21.5mm: The bottom diameter of the reel should not be less than 12.5 times the outer diameter of the cable.
4. Configuration requirements of suspended cable trolley
When using a suspended cable trolley, the cable should be prevented from being worn, tangled or excessively bent during operation:
Cables with an outer diameter ≤ 8mm: The curvature diameter of the suspension bending plate should be ≥ 6.3 times the outer diameter of the cable.
Cables with an outer diameter > 8mm and ≤ 12.5mm: The curvature diameter should be ≥ 8 times the outer diameter of the cable.
Cables with an outer diameter > 12.5mm: The curvature diameter should be ≥ 10 times the outer diameter of the cable.
Flat cable: Its thickness can be calculated according to the equivalent round cable diameter.
