Buffer rollers are used to reduce the impact of falling materials on the conveyor belt at the receiving point of belt conveyors. They are specifically designed for corrosive environments such as coal washing plants, coking plants, and chemical plants. These rollers have a toughness that is more than ten times that of ordinary metals, a lifespan five times that of traditional column shoes, and features such as corrosion resistance, flame retardancy, and anti-static properties, making them widely used in mining operations. The roller body is made of specialized polymer materials, which have mechanical properties similar to bronze, excellent wear resistance, and good self-lubricating properties that do not damage the belt. The corrosion resistance of buffer rollers is superior, with both the roller body and sealing components made from polymer materials that are resistant to corrosion. In corrosive environments, their lifespan can exceed that of ordinary rollers by more than five times.

Buffer rollers are lightweight and have low rotational inertia. The specialized polymer material used for the rollers is lightweight, with a specific gravity one-seventh that of steel. Rollers made from this material weigh about half that of ordinary rollers, resulting in low rotational inertia and reduced friction between the rollers and the belt.

Buffer rollers are installed below the receiving section of the conveyor to reduce the impact of materials on the conveyor belt during dropping, thereby extending the lifespan of the conveyor belt. The spacing of buffer rollers is generally between 100-600 millimeters.

For the installation of buffer rollers, it is important to increase the installation density and regularly check and replace damaged rollers in a timely manner. For conveyors with a large drop in material, it is recommended to install a buffer lock device and replace the buffer rollers with a buffer bed. When purchasing, consider the following points based on the characteristics of buffer rollers: radial runout, roller flexibility, axial movement, dustproof performance, waterproof performance, axial load capacity, and impact resistance.

(1) Temperature protection for buffer rollers

When the temperature exceeds the limit due to friction between the conveyor drum and the belt, a detection device installed close to the drum sends out an over-temperature signal. After a 3-second delay, the receiving device will trigger the execution part to cut off the power supply to the motor, causing the conveyor to stop automatically, thus providing temperature protection.

(2) Speed protection for roller groups

If a fault occurs in the conveyor, such as motor burnout, damage to the mechanical transmission parts, belt or chain breakage, or belt slippage, the magnetic switch in the accident sensor SG installed on the passive components of the conveyor will not close or will not close at the normal speed. At this time, the control system will activate the speed protection circuit after a certain delay according to the reverse time limit characteristics, triggering the execution part to cut off the power supply to the motor to prevent the accident from escalating.

(3) Coal level protection for buffer roller coal bins

The coal bin is equipped with high and low coal level electrodes. When the coal bin cannot release coal due to the absence of empty cars, the coal level will gradually rise. When the coal level reaches the high-level electrode, the coal level protection will activate, causing all conveyors to stop sequentially due to coal accumulation at the tail of the first belt conveyor.