Theoretical analysis of the impact of belt speed on indentation rolling resistance

Wroclaw University of Science and Technology, Faculty of Geoengineering, Mining and Geology, 27 Wyb. Wyspianskiego St., 50-370 Wroclaw, Poland

^* Corresponding author: martyna.konieczna@pwr.edu.pl

Abstract

Belt conveyors, having high reliability and efficiency, are the main means of continuous transportation both in underground and in open-cast mining. Despite their numerous advantages, however, belt conveyors are expensive in maintenance. Therefore, improvements in the field of belt conveyor transportation largely focus on methods for lowering their power consumption. The energy consumption level of a belt conveyor depends on the motion resistances which occur during its operation. In the case of conveyors having lengths greater than 80 m, main resistances are the dominant component of motion resistances, and up to 60% of main resistances may be accounted for by the rolling resistances of the belt on idlers. Motion resistances, including rolling resistances, have long remained an object of research. Extensive laboratory tests and increasingly detailed theoretical models allow a better insight into the phenomena involved in the movement of the belt on the conveyor. Different research results place different weight on the influence of individual parameters (such as unit load or phase lag angle) on belt rolling resistance. The greatest inconsistencies, however, are observed in the analyses of belt speed impact, which is occasionally not even included in some models. This paper discusses the known and commonly used methods for determining the rolling resistances of the belt on idlers. It also proposes a new solution, which employs the analysis of strain variation in the belt for successive load cycles to determine whether belt speed has a direct influence on the value of rolling resistance.