Saturday, October 2, 2021

Belt Conveyor Drive Arrangement | Belt Conveyor Design Calculation

Drive arrangement:

01-belt conveyor elevator-belt conveyor equipment-belt conveyor frame-belt conveyor grain handling-belt conveyor accessories

In belt conveyors the driving power is transmitted to the belt by the driving pulley which is rotated by an electric motor. The basic mechanism of transmission of power from the pulley to the belt is based on the theory of friction drive.

The fundamental equation for a belt conveyor drive is given by: (The Euler's equation)

T1 ≤ T2.eµα

Where,

          T1 and T2 are the tight side and slack side tensions of the belt at the driving pulley

          α = wrap angle of the belt in radiation

          e = Naperian base

          µ = Friction factor

The peripheral effective pull TE from a driving pulley, neglecting losses on the driving pulley due to belt stiffness is determined from the following reaction:

T= T1 – T2

T2min > T E Max (1 / (eµα -1))

Where,

E Max is the maximum effective peripheral pull in N, which often occurs when starting up or when braking the completely loaded conveyor.

In other conditions Te is the average effective pull. Maximum effective pull is usually 20% to 50% more than the average effective pull, depending on the type of motor starter and coupling.

Table: Coefficient of friction between driving pulley and rubber belting type of pulley lag

Operating conditionsSmooth bare steel pulleyRubber lagging with herring bone groovesPolyurethane lagging with Herring bone groovesCeramic lagging with Herring bone groovesPVC belt
Dry0.35 to 0.40.4 to 0.450.35 to 0.40.4 to 0.450.25 to 0.35

Clean wet (Water)

0.10.350.350.35 to 0.40.15 to 0.3

Wet and dirty ( Clay or Loam)

0.05 to 0.10.25 to 0.30.20.35Less than 0.25

The value of α depends on the particular drive system selected and may range from 180° to maximum 440°.

Minimum belt tension

T = 4.2 Pc ( Wb + Wm )

Where,

Pc = idler spacing on the carrying side

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