A roller bit

• 牙轮钻头

A roller bit的用法和样例：

例句

1. The desig ner should consider comprehensively the effect of structure data and radial clea rance on the life of the roller bearing, in order to make optimum design.
   钻头设计要优化轴承结构参数和径向游隙，以提高国产牙轮钻头的寿命。