托辊按其用途分类为调心托辊、缓冲托辊、槽形托辊、平行托辊。调心托辊的作用是纠正带式输送机的跑偏，通常输送机的重载段上安装回转式槽形调心托辊，空载段上安装平行调心托辊。缓冲托辊是根据实际情况应用于机尾架上的，受料时，可以降低物料对皮带的冲击，有利于沿长液压钢坝  皮带的使用寿命。
Idler is classified into centering idler, buffer idler, trough idler and parallel idler according to its application. The function of the self-aligning idler is to correct the deviation of the belt conveyor. Generally, the rotary groove self-aligning idler is installed on the heavy-duty section of the conveyor, and the parallel self-aligning idler is installed on the no-load section. The buffer idler is applied to the tailstock according to the actual situation. When receiving the material, it can reduce the impact of the material on the belt, which is conducive to the service life of the belt along the length