单牙轮钻头轴承载荷测试与分析

Test and analysis of forces on bearing of mono cone bits

用带传感器的试验用单牙轮钻头，在改变轴倾角、钻压和转速的条件下进行钻头轴承载荷的台架试验，得到动载荷系数、轴向力、径向力、周向力、扭矩和牙轮传动比等数据。对实测和计算数据的分析表明，单牙轮钻头的动载荷系数基本不随钻压、转速和轴倾角变化，并且比三牙轮钻头低；轴向力和径向力随钻压的增加而增加，且受轴倾角的影响；周向力随扭矩的增加而增加；牙轮传动比小于１，基本不受钻压和转速的影响，但与轴倾角有关。有限元分析表明，轴承内部存在三个应力集中区域。

By means of a special prototype mono cone bit provided with a sensor, the data on dynamic load coefficient, axial force, redial force, circumferential force, torque and cone drive ratio are obtained on a test stand by changing the axle tilt angle, weight on bit and romp speed. Analysis of the data measured and calculated shows: the dynamic load coefficient of the ￣ cone bit doesn't vary basically with the weight on bit, rotary speed and axle tilt angle and is minor than that of the tricone bit; the edal force and radial force increase with the weight on bit and are under the influence of the axle tilt angle; the circumferntial force increases with the torque; the drive ratio of cone is less than 1 and is related to the axle tilt angle but basically not to the weight on bit and rotary speed. Finite element analysis shows that there are three stress concentration areas inside the bearing.