The critical factors are:

1. discharge belt speed

2. moisture content of sand

3. drop height

4. trough angle of discharge conveyor

5. plan view of included angle between discharge and receiving conveyor (ie in-line to 90 degrees or more)

6. angle of elevation( + or -) for discharging uphill or downhill and the same for receiving conveyors

7. internal geometry of chute

The difference in speed between the two belts is best solved using Discrete Element Modeling (DEM) (see our website)

Ideal conditions are where the material flow is accelerated or maintained or decelerated to match the receiving belt speed and which minimize velocity gradients within the chute. ■

Assuming you are using the same size/speed belts the belt drive timers/controls are your biggest advantage-always start the belt closest to the end point first and start the second one 20 or 30 seconds later. ■

In the first posting I assumed the two belts were about the same speed.

My first response dealt with the chute flow and placing the product onto the receiving belt at its operating speed.

If you are refering to the stopping condition where there is a build-up of product in the chute, then you have many choices. You can install brakes on the feed conveyor to stop in the same time as the receiving conveyor. You may need to apply some flywheel inertia to the receiving conveyor. You may elect to increase the speed of the receiving to get the coasting times to favor the receiving belt and minimize chute build-up. ■

Dear Jim Moran

your question is not clear why you want to keep difference in speed of two conveyors

A R SINGH ■

Jim

Assuming that the receiving conveyor is the same size as the feeding conveyor they can be at the same speed. Care must be taken in any transfer to eliminate spillage by a properly designed transfer chute and loading station.

If the recieving conveyor is smaller than the feeding conveyor (rare but I have seen it) then the receiving conveyor must be appropriatley faster to accomodate the load.

The speeds can be determined by formulas (software packages are also available) but one must know all the specs of the product, the conveyors and the TPH required.

Gary Blenkhorn ■

There are many software programs that you can download for a trial period that you should be able to get the answers you need.

Here are a few to check out. The formulas are too complex to get into here in the forum.

Beltsat

http://www.conveyor-dynamics.com/resources/software.htm

Belt Analyst II

http://www.overlandconveyor.com/software/ba2/index.htm

Helix Delta-T

http://www.helixtech.com.au/newpage133.htm

Mine Conveyor

http://www.mineconveyor.com/mcvspec.htm

Regards

Gary ■

Here's a website that can give you a quick calculation but it is in metric.

http://www.bulkhandling.nl/site/prog...ite=NL&lang=UK

Gary ■