But now the use of the spherical one-cone bit shows that the teeth are abrade heavily in advance, which affects the velocity and life of the bit.
但是目前油田上使用的球形单牙轮钻头由于牙齿先期磨损严重，影响了钻头的机械钻速和寿命。
2
The studying results show that the classical elastic wave equation of spherical wave is only true for fixed amplitude phase and described only kinematic equation of phase velocity.
研究揭示经典的球面波波动方程只对固定振幅相成立，即只描述了相的运动方程，其波速为相速度。
3
The reasons for error cut-in grinding of cage spherical outside surface of ball basket constant velocity joint is analyzed, and the solution for the problem is put forward.