Current status and future prospects of scraper conveyor lightweight technology

With the continuous expansion of coal mining scale in China, longwall faces are developing toward ultra-long lengths exceeding 600 m. For a 600 m scraper conveyor alone, the combined mass of the chains and scrapers exceeds 200 t, and the power consumption of the chain drive system accounts for approximately 30% of the rated full-load power. To address issues such as excessive chain mass, high overall energy consumption, and material redundancy, lightweight design has gradually become a key technical approach for improving the operational reliability and economic efficiency of scraper conveyors. This paper focuses on lightweight technologies for scraper conveyors and systematically reviews the current research status and development trends both domestically and internationally. Material lightweighting is currently a major research focus. High-performance non-metallic materials, such as carbon fiber composites, ultra-high-molecular-weight polyethylene, and rock-based composite materials, exhibit low density and excellent wear and corrosion resistance, demonstrating promising potential for application in components such as scrapers and middle troughs. Lightweight metallic materials, including aluminum-alloyed high-manganese steels, can achieve substantial weight reduction while maintaining adequate strength and service life. In addition, surface strengthening and modification technologies—such as laser cladding, plasma surfacing, and bionic surface structures—enhance wear resistance and indirectly reduce material redundancy by extending component service life, thereby contributing to lightweight design. Structural lightweighting also plays an important role through advanced design optimization methods. Topology optimization, parametric optimization, and structural layout optimization have been widely applied to key components such as chain links, scrapers, middle troughs, and gearbox housings, achieving varying degrees of weight reduction. In particular, structural layout optimization approaches—such as multi-motor series driving and scraper spacing optimization—balance power and load distribution at the system level, further promoting lightweighting without altering individual component structures. In addition, low-friction chain transmission systems reduce sliding friction between scrapers and middle troughs through tribological design, thereby lowering energy consumption and wear and providing an alternative pathway for lightweighting. Despite these achievements, existing lightweight research still exhibits notable limitations. Some lightweight materials show insufficient mechanical stability under complex operating conditions. Many studies remain at the simulation stage and lack long-term underground engineering validation; certain optimized structures require high machining precision and incur elevated manufacturing costs, hindering large-scale application. Meanwhile, under coal dust and moisture conditions, the performance of low-friction transmission systems tends to degrade over time, and their manufacturing and maintenance costs remain relatively high, restricting practical implementation. Future research should emphasize multi-objective collaborative optimization, balancing weight reduction with strength, service life, and manufacturing cost. At the structural level, further exploration of optimized and disruptive design concepts—such as replacing traditional round-link chains with wire-rope-driven systems—should be pursued. In terms of materials, accelerated development and application of novel high-strength lightweight materials are required. Meanwhile, deeper integration of lightweight design with advanced manufacturing technologies, such as additive manufacturing, should be promoted, together with enhanced integration and comprehensive application of lightweight technologies, to ultimately achieve overall lightweighting of scraper conveyors. In summary, lightweight research on scraper conveyors is not only an important approach to addressing energy security and low-carbon development requirements, but also a necessary pathway for promoting intelligent and green development in coal mining.