Review on the Structure and Performance of Conveyor Belts as Key Core Constituents in Belt Conveyor Systems.

Abstract

        Belt conveyors are the core equipment for continuously conveying bulk materials in industrial sectors such as mining, metallurgy, chemical engineering, ports, and building materials. They offer significant advantages including long conveying distances, large transport capacity, low energy consumption, stable operation, and strong adaptability. As the most critical load-bearing and traction component of a belt conveyor, the conveyor belt directly determines the equipment’s conveying capacity, operational stability, service life, and safety performance. It is the fundamental element that ensures the efficient, continuous, and reliable operation of the entire belt conveyor system. This paper systematically elaborates on the core structural composition, classification system, essential functions, and key performance indicators of conveyor belts. It also reviews the synergistic working mechanisms between the conveyor belt and other auxiliary components of the belt conveyor, and summarizes the application characteristics and technical requirements of conveyor belts under industrial operating conditions. The aim is to provide theoretical references and technical support for equipment selection, operation and maintenance optimization, and structural upgrades of belt conveyors.

Introduction

        Belt conveyors, characterized by their continuous, automated, and large-scale material conveying capability, have become the primary equipment for bulk material transportation in modern industry and are widely used in various bulk material transfer scenarios. The entire belt conveyor system consists of multiple components that work in synergy, including the conveyor belt, driving device, pulleys, idlers, tensioning device, cleaning device, braking device, and others. Each component performs its designated function while coordinating with the others to jointly accomplish the complete process of material loading, traction, conveying, and protection. Among these, the conveyor belt is the only component that extends throughout the entire equipment and directly contacts both the material and the supporting structures. It serves as the core component, bearing multiple roles such as carrying materials, transmitting traction forces, and adapting to operational deformations. Its structural design, material properties, and specifications directly determine the conveying efficiency, operational energy consumption, failure probability, and service life of the belt conveyor. Compared with other auxiliary components, the conveyor belt is a consumable yet highly adaptable core component, and its technological iteration and performance optimization represent the key breakthrough point for enhancing the overall performance of belt conveyors. Therefore, systematically reviewing the composition structure, functional characteristics, and technical requirements of conveyor belts holds significant engineering importance for ensuring safe operation, efficient maintenance, and energy conservation and consumption reduction in industrial belt conveyor applications.

Core Composition Structure of Conveyor Belts

        The conveyor belt is a multi-layer composite integrated flexible component. Its overall structure follows the design principle of "load-bearing by the reinforcing layer, protection by the protective layer, and consolidation by the bonding layer." The structure features distinct layers with clearly defined functions, consisting primarily of four parts: the skeleton reinforcing layer (carcass), the upper and lower cover rubber layers, the bonding and buffer layer, and the edge protection layer. These structural layers work synergistically to collectively ensure the mechanical properties, wear resistance, aging resistance, and overall stability of the conveyor belt. To visually present the core parameters and functional differences of each structural layer, the layered structural parameter comparison table of the conveyor belt is organized as follows.

    1.Skeleton Reinforcing Layer

        The skeleton reinforcing layer (carcass) is the primary load-bearing matrix of the conveyor belt and the key structure that determines the tensile strength, load-carrying capacity, tear resistance, and dimensional stability of the belt. It primarily undertakes the entire traction tension and material loads during belt conveyor operation. Based on differences in material and structural configuration, the reinforcing layer can be divided into two major categories: fabric core and steel wire rope core. The fabric core is typically formed by multi-layer interweaving of fibrous materials such as canvas, polyester, and nylon, featuring good flexibility, light self-weight, and strong adaptability. It is suitable for light-to-medium loads, short-distance transportation, and conventional operating conditions. The steel wire rope core is fabricated using high-strength galvanized steel wire ropes arranged in parallel, offering extremely high tensile strength, minimal deformation, and excellent impact resistance. It can meet the conveying requirements of long distances, large capacities, high tension, and heavy-duty harsh conditions, making it the mainstream reinforcing structure for large-scale industrial belt conveyors. The material specifications, number of layers, and arrangement density of the reinforcing layer directly determine the rated tension and maximum load limit of the conveyor belt.

    2.Upper and Lower Cover Rubber Layers

        The cover rubber layers constitute the surface protective structure of the conveyor belt, consisting of the upper cover rubber (carrying side) and the lower cover rubber (non-carrying side). They are made of high-elasticity, high-wear-resistant, anti-aging rubber or polymer composite materials. The upper cover rubber directly contacts the conveyed material and primarily serves to buffer material impact, prevent abrasion from the material, avoid material adhesion, and simultaneously protect the internal skeleton reinforcing layer from scouring, corrosion, wear, and external mechanical damage. The lower cover rubber directly contacts the idlers and pulleys, requiring excellent wear resistance and a low coefficient of friction, which can effectively reduce operational resistance, minimize mutual wear between idlers and the conveyor belt, and lower the equipment's energy consumption. Depending on the operating conditions, the cover rubber can be formulated with special modifications such as wear resistance, heat resistance, cold resistance, acid/alkali resistance, flame retardancy, and anti-static properties to meet the protective requirements of various industrial applications.

    3.Bonding and Buffer Layer

        The bonding and buffer layer is positioned between the reinforcing layer and the cover rubber layers. Composed of high-elasticity rubber compound, it serves as the transitional consolidation structure of the conveyor belt. Its core function is to ensure intimate bonding between the reinforcing layer and the cover rubber layers, eliminate interlayer gaps, and enhance the overall integrity and structural stability of the conveyor belt. In addition, it buffers impact loads generated by material dropping and equipment start-stop operations, disperses localized stresses, and prevents failures such as fracture, delamination, and debonding of the reinforcing layer caused by stress concentration, thereby effectively improving the impact resistance and fatigue life of the conveyor belt. For conveying conditions involving large-sized and heavy materials, a thickened buffer layer can significantly enhance the impact protection capability of the conveyor belt.

    4.Edge Protection Layer

        The edge protection layer is a sealing and protective structure on both sides of the conveyor belt, formed integrally from dense rubber material. During conveyor belt operation, the edges are prone to friction and compression against the frame and the conveyed material, and are also susceptible to ingress of moisture, dust, and corrosive media. The edge protection layer effectively seals the interlayer gaps, preventing moisture and impurities from penetrating into the interior and corroding the reinforcing layer, while also preventing edge wear, cracking, and delamination. It enhances the overall sealing performance and structural durability of the conveyor belt, and significantly reduces the probability of edge damage and overall belt failure.

Core Functions and Working Mechanism of Conveyor Belts

        Within the complete belt conveyor system, the conveyor belt fulfills three core functions: material loading, power transmission, and operating condition adaptability, serving as the primary medium for achieving continuous conveying. During operation, the driving device of the belt conveyor drives the driving pulley to rotate, transmitting traction force through friction between the pulley and the conveyor belt, thereby driving the belt to perform closed-loop continuous cyclic motion. The conveyed material is placed steadily on the working surface of the conveyor belt and is continuously transferred by the belt's movement. Meanwhile, owing to its flexible structural characteristics, the conveyor belt can accommodate the supporting structure of the idler sets, adaptively fine-tune its running posture, and suit various conveying configurations such as horizontal, inclined, and uphill transport, demonstrating excellent operating condition adaptability and running stability. Furthermore, modified conveyor belts can be adapted to special conditions including high temperature, low temperature, flammable and explosive environments, and corrosive atmospheres, ensuring the safety and stability of material conveying under demanding circumstances.

Classification and Operating Condition Adaptability of Conveyor Belts

        Based on structural materials, performance parameters, and applicable operating conditions, industrial conveyor belts are mainly classified into three categories: fabric-core conveyor belts, steel wire rope-core conveyor belts, and special-function conveyor belts. The performance characteristics and application scenarios of each type differ significantly. To clearly distinguish the applicable scenarios and performance advantages of each type, a comparison table of conveyor belt types and their operating condition adaptability is organized as follows.

Conclusions

        As the core load-bearing and traction component of belt conveyors, the conveyor belt features a multi-layer composite structural design that integrates the functions of mechanical load-bearing, surface protection, cushioning and shock absorption, and sealing protection. It serves as the fundamental basis for ensuring the efficient, stable, and safe operation of belt conveyors. The skeleton reinforcing layer determines the load-carrying and tensile performance of the conveyor belt; the cover rubber layers provide operational protection, wear resistance, and friction reduction; and the buffer layer and edge protection layer ensure structural integrity and durability. Each structural layer works in synergy with the others, and none is dispensable. Conveyor belts with different structures and materials are adapted to diverse industrial operating conditions, meeting production requirements across varying conveying distances, load intensities, and environmental conditions. Against the backdrop of industrial intelligence and high-efficiency development, conveyor belts are undergoing iterative upgrades toward higher strength, superior wear resistance, extended service life, intelligent functionality, and multi-functional composite integration. Through structural optimization and material modification, further improvements in the overall conveying efficiency and operational reliability of belt conveyors can be achieved, along with reductions in equipment operation and maintenance costs, thereby providing core support for energy conservation, efficiency enhancement, and safe and stable operation of industrial continuous conveying systems.

References

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