托輥是帶式輸送機的重要部件，種類多，數量大。它占了一臺帶式輸送機總成本的35%，產生了70%以上的阻力，因此托輥的質量尤為重要。
Idler is an important part of belt conveyor with many types and large quantities. It accounts for 35% of the total cost of a belt conveyor and produces more than 70% resistance, so the quality of the idler is particularly important.
托輥的作用是支撐輸送帶和物料重量。托輥運轉必須靈活可靠。減少輸送帶同托輥的摩擦力，對占輸送機總成本25%以上的輸送帶的壽命起著關鍵作用。雖然托輥在帶式輸送機中是一個較小部件，結構并不復雜，但制造出高質量的托輥并非易事。
The idler is used to support the conveyor belt and material weight. Idler operation must be flexible and reliable. Reducing the friction between the conveyor belt and the idler plays a key role in the service life of the conveyor belt, which accounts for more than 25% of the total cost of the conveyor. Although the idler is a small part in the belt conveyor and its structure is not complex, it is not easy to manufacture high-quality idler.
判斷托輥好壞的標準有以下幾條：托輥徑向跳動量；托輥靈活度；軸向竄動量。
There are the following criteria for judging the quality of idler: radial runout of idler; Idler flexibility; Axial displacement.
