Conveyor Belt Speed Calculator
Find the belt speed of a conveyor from the drive roller, gearbox and motor speed, or the motor speed needed for a target belt speed.
Drive
Use the diameter of the roller plus belt thickness if you want the effective pitch diameter. Include any belt or chain reduction in the gear ratio.
Belt speed from motor speed
Motor speed for a target belt speed
How it works
One turn of the drive roller moves the belt a distance equal to the roller's circumference. The roller turns at the motor speed divided by the gear reduction, so belt speed is circumference times roller RPM.
belt speed = π × diameter × roller RPM
motor RPM = belt speed × gear ratio / (π × diameter)
Worked example
A 6 in drive roller is driven by a 1750 RPM motor through a 25:1 gearbox.
- Roller speed = 1750 / 25 = 70 RPM.
- Belt speed = π × 6 × 70 = 1,319 in/min = 110 ft/min (about 33.5 m/min).
To reach 100 ft/min with the same roller and gearbox, the motor needs about 1,592 RPM. On a VFD, that is roughly 91% of 60 Hz for a motor that runs 1750 RPM at 60 Hz.
Common questions
Does belt slip matter?
Yes. The calculation gives the ideal speed. Slip on the drive roller, belt stretch and load all reduce actual speed, so measure on the machine for anything that needs precision.
How do I find the gear ratio of a gearmotor?
It is on the nameplate as a ratio (such as 25:1), or it can be found by dividing the motor RPM by the output RPM.
Calculations are provided for convenience and education. Verify results on the machine before relying on them.