| 1. | Prediction of drill string ' s fatigue life under torsion and axial vibration
纵向振动下的疲劳寿命估算 |
| 2. | Torsional vibration simulation analysis of drilling string and rock bit
钻井用钻头和钻柱扭转振动的仿真分析 |
| 3. | Study on the lateral vibration rule of drilling string under reversion
对钻柱在反转情况下横向振动规律的研究 |
| 4. | Vibration absorber for drilling string
钻柱减震器 |
| 5. | New method for geometric nonlinear analysis of large displacement drill strings
一种新的大位移井钻柱几何非线性分析方法 |
| 6. | The rotary carriage provides rotary and vertical motion to the drill string and bit
转动滑架为钻柱和钻头提供转动和垂直移动。 |
| 7. | Study of contact force between drill string and borehole wall in constant - curvature wellbores
等曲率井眼中钻柱与井壁间接触力分析 |
| 8. | Its main functions are maintaining borehole gage , improving drill string stability and protecting lower drill string from excessive wear
其重要作用是保持钻头尺寸符合标准，提高钻杆稳定性，避免钻杆下部过于磨损。 |
| 9. | The calculation results demonstrate the effective eccentricity and the lifting force of the upper drill string are the major influential factors
计算结果表明，有效偏心距和上部钻柱的提升力是影响近井口套管偏磨的主要因素。 |
| 10. | In chapter two , the prosperity of the motion , force and screwed joint of the surface dynamic rotating drilling downhole drilling string has been discussed
第二章分析探讨了地面动力旋转钻井井下钻柱的运动状态、受力及螺纹联接的特性。 |
