It is the main component of the transmission of power. The roller can be divided into a steel surface roller, a drum and a ceramic drum. The roller (the angle of the tape is 210 to 230 degrees to the drum), the double roller (the angle of the bag is 350 degrees) and the multiple rollers (for high power). The smooth roller is easy to manufacture, and the drawback is that the surface friction factor is small, which is usually used in short distance conveyor. The main advantage of the rubber drum and ceramic drum is the large surface friction factor, which is suitable for long distance large belt conveyors. Among them, the package roller can be divided into two parts: light bread glue roller, rhombus (mesh) rubber roller and human shaped grooved rubber drum. Herringbone groove adhesive surface has large friction factor, good skid resistance and drainage, but there are directional requirements. Rhombus rubber surface is used for two-way operation of conveyor. For vulcanized rubber surfaces, it is better to use vulcanized rubber. When used for downhole, the rubber surface should be flame-retardant glue surface material.