DETERMINING THE CAPACITY REQUIREMENTS OF COAL MINE GATHERING BELTS.

摘要

In coal mining the belt haulage system can be resolved into three component belt types: section belts, transfer belts, and gathering belts. In contrast to section and transfer belts which receive loads from a single source, gathering belts receive loads from two or more sources. Therefore the capacity requirements for these belts are dependent upon the individual source loads that will superimpose on them. Since belt loading is intermittent and often of short and varying duration, it is difficult to determine the extent of this superimposing. Consequently, the capacity requirements of gathering belts can not be exactly calculated, but they can be predicted by either empirical formulas or computer simulation models. While simulation models are considered to be accurate, their application is often very time consuming and burdensome. Hence, in the preliminary stages of mine design and also when decisions must be made quickly, reliable empirical methods are often preferred.; In order to establish their reliability, an evaluation of the empirical methods for designing gathering belt capacity was undertaken in this study. The first step in this evaluation consisted of identifying the existing empirical methods. Only two were found: the safety factor method and the peak capacity method.; Since it was not possible to apply the empirical designs to operating belt systems and then evaluate their effects directly, a computer simulation model was needed for this purpose. Although several simulation models are available, all of them contain deficiencies. Therefore, a substantial portion of this study involved developing a new model which would overcome many of these deficiencies. When this new model is applied, a more realistic and accurate belt capacity simulation can be achieved.; Once the new model was developed and field loading data was collected, simulations were made to evaluate numerous empirical designs that were applied to hypothetical belt systems. These evaluations lead to recommendations for applying the peak capacity and safety factor methods, a new empirical method, and recommendations for further study. If the recommendations and the new empirical method are applied, reliable empirical design can be achieved.