Full definition
The bottom cover of a conveyor belt is a critical component that serves as the protective layer on the pulley-side surface of the belt. This rubber layer is engineered to withstand the rigors of contact with return idlers, pulleys, and slider beds during operation. According to the DIN 22102 standard, the standard thickness of the bottom cover typically ranges from 1.5 mm to 3 mm. The material used for the bottom cover must be designed to minimize abrasion, classified as Type Y, which has a maximum abrasion loss of 150 mm³ as per ISO 4649. This low-abrasion characteristic is essential for extending the lifespan of the belt while maintaining operational efficiency.
In addition to abrasion resistance, the bottom cover must exhibit a low coefficient of friction. This property is vital to reduce heat buildup when the belt operates under conditions of high friction, such as in tightly spaced pulleys or high-load scenarios. Excessive heat can lead to premature failure of the belt, necessitating costly replacements and downtime. Therefore, selecting the right material for the bottom cover is crucial in balancing durability with operational performance.
In specific applications, such as underground mining, the bottom cover must also adhere to antistatic requirements. The maximum resistivity for these applications is set at 3×10⁸ Ω according to ISO 284. This ensures safety by preventing static electricity buildup, which could ignite explosive atmospheres commonly present in mining environments. Hence, the bottom cover is not only a wear-resistant surface but also a safety feature that plays a crucial role in maintaining operational integrity in hazardous conditions.