You must also consider the ore path just prior to leaving the chute. Ideally, you have configured the chute to match the belt line velocity and minimize the tranverse and vertical velocities.

We practice preserving the kinetic energy leaving the discharge station, preserving the gravitational forces in a hood and spoon arrangement, and selecting the chute geometry to minimize dust generation along the chute path. ■

Yes, you must test for adhesion and cohesion if you have a fine particle base (< 0.25 mm > 10% by volume) and if you have surface moisture.

If you have a very fine particle base, you may also need to test for electrostatic and atomic attractions - Van der Waahl, Einstonian, and Zeta Potential forces, ect.

You also need to test for various friction values:

a) particle-to-particle friction,

b) particle-to-belt,

c) particle-to-chutewall friction,

d) particle-to-skirtboard friction.

We know the ore friction is dependent on particle shape, size distribution, surface texture, moisture and any plasticity tendencies or attrition behavior.

Chute wall texture and ore consolidation can play very important roles in controlling the flow stream in a desired manner.

CDI is designing chutes that control flow and large rocks up to 24,000 t/h onto high speed conveyors with varying loading angles. Is your range above this design point? ■