The belt conveyor is used for conveying different materials from one location to another. The different components of a belt conveyor system typically are electric drives, pulleys, idlers, and a long belt. A simple conveyor system may look like below:
The basics of the Calculations of Conveyor Belt Design Parameters
- Belt tension: The belt of the conveyor always experience a tensile load due to the rotation of the electric drive, weight of the conveyed materials, and due to the idlers. The belt tension at steady state can be calculated as:
Tb = 1.37*f*L*g*[2*mi+ (2*mb + mm)*cos (δ)] + (H*g*mm)…….eqn.1.1
mi = Load due to the idlers in Kg/m.
mb = Load due to belt in Kg/m.
mm = Load due to the conveyed materials in Kg/m.
δ = Inclination angle of the conveyor in Degree.
H = vertical height of the conveyor in meters.
- Load due to idlers (mi): This can be calculated as below:
mi = (mass of a set of idlers) / (idlers spacing) ……………..eqn.1.2
Note: The article “Design an Idler for a Conveyor Belt System” has detailed explanation about how to calculate idlers spacing.
- Power at drive pulley: The power required at the drive pulley can be calculated from the belt tension value as below:
Pp = (Tb*V)/1000……………..eqn.1.3
Pp is in KW.
Tb = steady state belt tension in N.
Tb is in Newton.
f = Coefficient of friction
L = Conveyor length in meters. Conveyor length is approximately half of the total belt length.
g = Acceleration due to gravity = 9.81 m/sec2
v = belt speed in m/sec.
- Belt tension while starting the system: Initially during the start of the conveyor system, the tension in the belt will be much higher than the tension in steady state. The belt tension while starting can be calculated as:
Tbs is in N.
Tb = the steady state belt tension in N.
Ks = the start-up factor
- Sizing of the motor: The minimum motor power can be calculated as:
Pm = Pp/Kd………………eqn.1.5