Improved Conveyor Design

The main idea that keeps material handling competitive is optimization. The design of the conveyor system should be cost-effective while remaining technically sound.

The current version of the conveyor design program has evolved from 2 earlier versions.

FIRST program: the design primarily delas with peoducing only the belt tensions at the head end, the motor power required and the belt safety factors based on the head end tensions. this program assumed the conveyor profile to be a straight line between the head and tail pulleys; and that all the materials to be carried is loaded at the tail.

SECOND program: this version was written so that the program is more use friendly. the conveyor designer now has the opportunity to move between the 4 pages of data and the main menu of the program options at the push of specifil Special Function Keys on the keyboard. This has greatly improved the time taken during the optimization phase, where quick changes of data are required between successive calculations.

An approximate tail tensions is calculated so that the necessary tension to limit sag on the carry side is checked at the point of least tension instead of at the head. Another addition was that once a suitable motor has been selected from a library within the program, the maximum starting tension, counterweight tension and belt safety factors are recalculated.

THIRD program: the most current conveyor program was a complete rewrite of the previous versions. the new program was written so the conveyor can be cut into many sections and each section is analyzed in turn. this means that conveyors of almost any configuration can be analyzed and that the designer can now have data regarding belt tensions and safety factors at any point along the conveyor.

FUTURE ENHANCEMENTS:

Conv 3 has proved to be the most useful and profitable tool. the following additions will be made to the program:

• print out of required take-up weight


• automatic input of belt weight and belt thickness from a library of commonly used belts.


• automatic belt selection, with the facility to override the selection when belt standardization over a number of conveyors is desired.


• computer generated sketch of conveyor outline, basically as a quick check to verify the input data.


• calculation of the belt stretch and take-up travel


• design of conveyors with two or more drive units located at different points


• automatic input of idler rotating wiehgts from a library of typical idlers


• idler selection


• linking our "SHAFT" program t calculate pulley shaft sizes


• pulley bearing selection


• holdback torque and holdback unit selection


• torque arm position and force


• calculation of power to CEMA formulae


• calculation of power to Pipe Conveyors


• horizontal and vertical curve analysis for Pipe Conveyors

In conclusion, the conveyor design by computer is proving to be a very cost effective exercise and even achieves a high degree of optimization. Also, the degree of confidence is possible and there is little chance left for any human error affecting the results.

taken from: Conveyor Belt Technology, 1987 (Reinhard H. Wohlbier)

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