The diameter of the driving drum must be chosen by balancing conveyor belt bending stress, rotational speed compatibility, and system efficiency. Below is a detailed method:
Bending Frequency: Higher speeds increase the frequency of belt bending over the drum, necessitating a larger diameter to reduce fatigue
.Empirical Formula: (D geq (125 sim 150) imes delta quad (delta = ext{total belt thickness, mm}))Use the upper limit for high-speed conveyors ((v > 4 , ext{m/s})).
Speed Compatibility: The drum rotational speed n relates to belt speed v as: (n = rac{60v}{pi D} quad ( ext{rpm}))Ensure n aligns with the reducer output speed (typically (n leq 300 , ext{rpm})).
Torque Formula: (T = F imes rac{D}{2} quad ( ext{driving torque})) (F = ext{belt tension}); ensure torque stays within reducer/motor ratings.
Power Compatibility: (P = rac{F imes v}{1000} quad ( ext{kW}))High-speed systems require larger diameters to reduce torque and avoid reducer overload.
Determine belt speed v and belt parameters ((delta), allowable tension).
Initial diameter: Calculate (D_{ ext{min}} = (125 sim 150)delta).
Verify speed: Ensure (n = 60v/(pi D)) matches the reducer output.
Calculate torque/power: Validate against system capacity.
Adjust diameter: Choose the closest standard size (e.g., 500, 630, 800 mm) that meets requirements.
Conditions: (v = 3 , ext{m/s}), (delta = 8 , ext{mm}).
Calculation: (D_{ ext{min}} = 150 imes 8 = 1200 , ext{mm})Use 1000 mm (standard size) and compensate with increased wrap angle or rubber surface.
Avoid undersizing: Small diameters cause premature belt failure or reducer overload.
Cost balance: Larger diameters increase costs; balance between service life and economy.
Dynamic testing: Validate vibration and temperature rise in high-speed systems during no-load trials.
By following these steps, the driving drum diameter can be optimized for conveyor speed, ensuring efficient and stable system operation.
