The conveyor belt is by its structure a textile composite. As a load-supporting element of the conveyor, the belt withstands variable loads during its operations. In order to investigate the influence of the level and variability of loading on the life of the belt, tests were carried out on specimens in laboratory conditions. A testing device was specially designed and made for these tests that enabled precise control and monitoring of the loading as well as number of loading cycles up to fracture. This research provides an overview of the influence of fatigue loading on the fatigue life of the belt. The methodology of the conducted research is explained with a description of important technical parameters of the testing device. A physical experiment and a corresponding numerical simulation using the FEM method were carried out with multiple loading levels of belt specimens. Based on the obtained results, appropriate conclusions were made; at loads less than 70% of the breaking strength, the lifetime of the belt is very long. Attention was drawn to additional influences that could not be covered by the experiment and possible directions for further research were indicated.

The paper presents an analysis of the possibility of optimizing the drive of slat conveyors, which primarily refers to the choice of the drive chain and the number of drive units. The basic characteristics of slat conveyors, as a mean of continuous transport, procedures for calculating the basic parameters and the choice of basic elements of the conveyor are presented. Cases with one angular and combinations with several line drive units are considered. In order to observe influential parameters, variants with different route lengths and line weight of transported material were considered. At the end of the paper, the obtained results were analyzed and appropriate conclusions were made.

The paper presents a case study of gravel transshipment in RTC Luka Leget in Sremska Mitrovica, R. Serbia. Problems that led to the incorrect operation of conveyors used in the transshipment of gravel from barges to the separation plant were analyzed. They included activation the safety switch of the conveyor drive, backward movement of the material on the belt, fracture of the connection tension pulley - axle, etc. It was found that ignorance of the actual force in the conveyor belt leads to most of the problems and the need of a solution for this problem was highlighted. At the end, proposed solutions were given in order to establish the normal operation of the plant and to prevent delays in gravel transshipment.

Bucket elevators is the most commonly used device for the transport of bulk, granular materials, from lower to higher levels. This role of the bucket elevators has been achieved thanks to its advantages, such as low power consumption, large capacities, high reliability and low maintenance costs. This paper is based on theoretical and practical analysis of the operation of the bucket elevators. The basic elements of the bucket elevators are presented in this paper, analyzing their advantages and disadvantages in practical application. The possibilities of electronic control of the bucket elevators operation as a basis for preventive maintenance are examined. The possibilities of modelling in modern software packages, individual elements of bucket elevators, primarily connecting elements, are presented. Considering that all the standards and recommendations from the practice, related to the use of bucket elevators, are covered by the analysis of the work and elements of the bucket elevators, this paper can serve as a guide in the selection and design of bucket elevators.

Hydrodynamic coupling is a power-transmitting device with no stiff kinematic relation between the shafts of its basic parts (pump and turbine impellers) and no torque transformation. It has been used in various driving mechanisms due to...