A system reliability-based design optimization for the scraper chain of scraper conveyors with dependent failure modes

Abstract

In the current coal mining face, the scraper conveyor (Fig. 1) as one of the key equipments for large-scale, high-efficiency and continuous coal mining equipment not only bears the role of coal transportation, but also the running track of the shearer and the shifting point of the hydraulic support [24]. Therefore, the scraper conveyor is throughout the fully mechanized mining face and occupies an extremely important position. As shown in Fig. 1, the scraper conveyor consists of one control cabinet, one double-chain drive system, two double-drive sprockets, one to three drive units and lots of middle troughs. With the development of high-yield and high-efficiency coal mining face, it is urgent to develop large-capacity, long-distance, high-power, high-reliability scraper conveyors [9]. The intent of the reliability-based optimal design is less maintenance or maintenancefree, resulting in objective economic benefits. The scraper chain (Fig. 2) is the core component of the scraper conveyor; its quality and performance directly affect the working efficiency of scraper conveyors. Due to the complexity and the harshness of the working condition, the scraper chain is prone to serious accidents. The coal production performance can be specifically attributed to the reliability of scraper chains. Therefore, it is considered necessary to introduce the structural reliability models throughout the design process to provide a more accurate reliability assessment and parameter optimization for the scraper chain with multiple failure modes. Random variables such as tensile force, structural dimensions and material properties of the scraper chain may affect its reliability. What’s more, in order to meet reliability requirements of the scraper chain, the random variables that have a significant impact on device SHUAI L, ZHENCAI Z, HAO L, GANG S. A system reliability-based design optimization for the scraper chain of scraper conveyors with dependent failure modes. Eksploatacja i Niezawodnosc – Maintenance and Reliability 2019; 21 (3): 392–402, http://dx.doi.org/10.17531/ ein.2019.3.5.