Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology
J. van Denzen De ophanging van de loop-belt conveyor.
Computer program, Report 95.3.TT.4482, Transport Engineering and Logistics.
During transport of bulk solids with conventional conveyor belts, a part of the transported material is blown off into the environment. By secluding the bulk solid from the environment this can be prevented. At Dunlop Enerka B.V. (Drachten, The Netherlands) a conveyor belt, called the loop-belt conveyor, is being developed which can be applied in such a closed transport system.
The resistance which the conveyor belt experiences proves to be in practise four to five times higher than in conventional conveyers. Supposedly this is caused by the carving of the bearing rolls into the tread of the belt. By changing the shape of the tread the carving may be prevented. To determine the effect of changing the shape of the tread, a calculation of the distortions and forces is made. This calculation is executed for the original shape and two alternative shapes with the finite elements program ANSYS. To be able to make the calculation with the ANSYS program, first a model of the reality has to be made. As the problem is 3-dimensional and the model 2-dimensional a number of assumptions have to be made. It is because of these assumptions that the results of the calculations can only be used to make a qualitative comparison between the different shapes.
At the original shape of the tread the carving indeed arises. At this spot a peak in the load occurs. At the first alternative shape the support of the tread gradually fades away by letting evade the contact surface of the tread. This results in the disappearing of the load-peak and the carving. The second alternative shape is based on the fact that the rolling resistance between two surfaces decreases as the contact length of these surfaces decreases. By applying the tread with a curved contact surface, this contact length may be decreased. Also, if at the place where the support roll ends no contact exists between the roll and the tread no carving can arise. From the calculation of this shape, it appears that due to the large distortions the contact length does not decreases and the carving can still arise.
Reports on Transport Engineering and Logistics (in Dutch)
