Single-idler belt conveyor (hereinafter referred to as belt conveyor), it is a general long-distance conveying equipment, combined into a conveying system by single unit or multi units, it is used for conveying of powdery, granular and small materials horizontal or inclined in a certain range, it can be widely used in grain, coal, electric power, metallurgy, chemical, mechanical, light industry, port, building materials and other industries.