文中采用传统的四球机法，对工投牌高扭矩钻具螺纹脂的摩擦系数进行了测试。

The paper measures the friction coefficient of Gongtou brand thread compounds for high torque drill tool.

youdao

文中采用传统的四球机法，对工投牌高扭矩钻具螺纹脂的摩擦系数进行了测试。

The paper measures the friction coefficient of Gongtou brand thread compounds for high torque drill tool.

youdao