Accelerated Comparative Fatigue Strength Testing of Belt Adhesive Joints

World Multidisciplinary Earth Sciences Symposium 2017

Bajda, Miroslaw^1 ; Blazej, Ryszard^1 ; Jurdziak, Leszek^1

Faculty of Geoengineering Mining and Geology, Wroclaw University of Science and Technology, ul. Na Grobli 15, 50-421, Poland^1

关键词: Comparative studies;    Reliability and durabilities;    Reliability of supply;    Reliability requirements;    Specialized equipment;    Strength of adhesive joints;    Strength parameters;    Underground coal mine;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/95/4/042053/pdf
DOI  :  10.1088/1755-1315/95/4/042053

来源: IOP

【 摘 要 】

Belt joints are the weakest link in the serial structure that creates an endless loop of spliced belt segments. This affects not only the lower strength of adhesive joints of textile belts in comparison to vulcanized splices, but also the replacement of traditional glues to more ecological but with other strength parameters. This is reflected in the lowered durability of adhesive joints, which in underground coal mines is nearly twice shorter than the operating time of belts. Vulcanized splices require high precision in performance, they need long time to achieve cross-linking of the friction mixture and, above all, they require specialized equipment (vulcanization press) which is not readily available and often takes much time to be delivered down, which means reduced mining output or even downtime. All this reduces the reliability and durability of adhesive joints. In addition, due to the consolidation on the Polish coal market, mines are joined into large economic units serviced by a smaller number of processing plants. The consequence is to extend the transport routes downstream and increase reliability requirements. The greater number of conveyors in the chain reduces reliability of supply and increases production losses. With high fixed costs of underground mines, the reduction in mining output is reflected in the increase in unit costs, and this at low coal prices on the market can mean substantial losses for mines. The paper describes the comparative study of fatigue strength of shortened samples of adhesive joints conducted to compare many different variants of joints (various adhesives and materials). Shortened samples were exposed to accelerated fatigue in the usually long-lasting dynamic studies, allowing more variants to be tested at the same time. High correlation between the results obtained for shortened (100 mm) and traditional full-length (3×250 mm) samples renders accelerated tests possible.