During an in-situ operation of machines, used for the exploitation of energy raw materials, a damaging impact of the environment on the components of these machines is experienced. The action of degrading factors is mostly shown in the form of a clear synergistic effect. In particular, this effect can be seen during an exploitation of driving elements of scraper conveyors, used as one of the basic machines in the hard coal mining process. In the article, the subject–matter, connected with an operation of sprockets in scraper conveyors, is presented. Special attention is paid to a mutual reaction of the mineral abrasive and the presence of mine water. The main objective of the research work was a determination of the interactive component of the factor causing an abrasive wear–quartz abrasive connected with the associated action and the factor intensifying electrochemical corrosion–water with and without the NaCl salt content. Experimental tests were conducted in the conditions similar to the reality, with the use of a test rig in the form of a short scraper conveyor. Within the framework of the test abrasive wear rates for the case of the abrasive presence itself and a mixture of the abrasive, salt and water were determined. Based on the obtained results, it appears that there is a synergistic impact of abrasive–corrosive mixtures on the wear of the surface layer of the chain sprockets under testing, and also, the causes of the interactive component values in the function of hardness and maximum strength of the materials under investigation are presented.
The paper presents results of testing the resistance of chain wheels made of alloyed austempered ductile iron (ADI) with various content of retained austenite and subjected to shot peening, to the dynamic and abrasive wear by solid particles. The impact of the additional environmental factor—external dynamic forces—accompanying the operation of the chain wheels in the presence of the quartz particles has a synergistic effect on the abrasive wear in the contact area between the wheels and the chain links for all the considered variants, except for the ADI with the structure of the upper ausferrite. Based on the results obtained, it was found that the abrasive wear by solid particles increased and that the hardness of the surface layer of the chain wheels subjected to shot peening decreased. The relative increase in the wear ΔVDYN/δMAX,(A), representing the share of the additional dynamic force in the process of wear, was in the range of 16–40% for the group of tested cast iron ADI not subjected to shot peening, while for the shot peened—in the range of 16–64%. Demonstration of phase changes during the operation of chain wheels and the change in their intensity depending on the combination of environmental factors is the work novelty. In the opinion of the authors, the presented results will be of great practical importance as they will allow to increase the knowledge on the proper selection of ADI cast iron for environmental conditions.
The article presents a methodology for testing the wear of chain links operating in a complex, degradation environment, taking into account the effects of abrasive, chemical, and dynamic factors. The design and construction of a test stand, enabling the recreation of real operating conditions with controlled selection of nominal and dynamic load parameters, mineral abrasive medium, and the presence of corrosive agents are described. The testing methodology, measurement procedures, and wear assessment methods are discussed. The results obtained during preliminary tests confirmed the suitability of the proposed methodology and test stand for analyzing the wear rate of conveyor chain joints under harsh operating conditions. The developed approach can be applied both in scientific research and in the designing process of more durable drive systems.
1 September 2025 in Scientific Journal of Silesian University of Technology. Series Transport
The article presents the impact of load on the contact surface of cooperating chain links in scraper conveyors. A finite element method (FEM) simulation was conducted for a chain operating on a sprocket, based on which stress and strain maps were determined for different load levels. The contact surface areas of the chain links and the reaction forces were also calculated depending on the load, which allowed the determination of surface pressures.