I am a Mechanical Engineer working in a company. Often, I have to select Holdback (Backstop) for belt Conveyor Application. I use following procedure to decide the Holdback Torque.
Holdback Torque = (A - B) x (Drive pulley radius)
Where,
A: Material Lift Resistance
B: [(Main Resistance considering conveying Friction coefficient 0.012) + 0.6 x (Sum of other Friction Resistances such as skirt board + Scrapers + Pulley turning & wrap + idler tilt Resistance)]
(If above value is negative, then it does not require Holdback)
We also analyse & take into consideration the occurring Rollback maximum Torque, due to selective presence of material on belt, such as material presence only on incline zone, etc.
The above procedures take reference to DIN/ISO stipulation that regenerative Power or Rollback Force calculation safety is by considering least value of Frictional Resistance i.e. by Friction coefficient least possible occurring values. The Holdback operational Torque rating should be equal/greater than the above calculated values. This required rating does not depend upon motor kW.
Holdback (Backstop) Selection for Belt Conveyor Application
I am a Mechanical Engineer working in a company. Often, I have to select Holdback (Backstop) for belt Conveyor Application. I use following procedure to decide the Holdback Torque.
Holdback Torque = (A - B) x (Drive pulley radius)
Where,
A: Material Lift Resistance
B: [(Main Resistance considering conveying Friction coefficient 0.012) + 0.6 x (Sum of other Friction Resistances such as skirt board + Scrapers + Pulley turning & wrap + idler tilt Resistance)]
(If above value is negative, then it does not require Holdback)
We also analyse & take into consideration the occurring Rollback maximum Torque, due to selective presence of material on belt, such as material presence only on incline zone, etc.
The above procedures take reference to DIN/ISO stipulation that regenerative Power or Rollback Force calculation safety is by considering least value of Frictional Resistance i.e. by Friction coefficient least possible occurring values. The Holdback operational Torque rating should be equal/greater than the above calculated values. This required rating does not depend upon motor kW.
The readers views on the subject are welcome. ■