水力振荡器在新场气田新沙21-28H井的应用

定向井水平井在滑动钻进时，托压、黏卡严重，如何提高滑动钻进钻压传递的有效性、减少钻具与井壁间的静摩擦，一直是待解决的技术难题。为此，分析了水力振荡器作用机理：通过一对阀门周期性的相对运动把流经动力部分的流体能量转化为压力脉冲，将该压力脉冲传递给振荡短节，由振荡短节带动钻具在轴线方向上进行往复运动，使钻具在井底的静摩擦变成动摩擦，既有效地实现了降低钻具摩阻，又达到了改善钻压传递的效果，且不影响MWD、螺杆钻具的使用。该工具首次在四川盆地西部新场气田的新沙21-28H井进行了提高钻速应用试验，在Φ172 mm振荡器的上下位置各接入1根加重钻杆，以预防钻具轴线蠕动造成钻具应力破坏。结果表明：加接该工具的滑动钻进机械钻速提高了45.16%、复合钻进机械钻速提高了30.00%，取得了非常显著的效果。该工具的应用需充分考虑钻井设备的工作能力，最大限度发挥其潜力。

Application of hydraulic oscillators to the development of Well Xinsha 21-28H in the Xinchang Gas Field,western Sichuan Basin

Horizontal directional drilling (HDD) involves serious backpressure and wall sticking during slide drilling, so how to maximize WOB transfer effectiveness and meanwhile minimize the static friction between drilling string and well wall has long been a technical problem yet to be solved. Therefore, the working mechanism of the hydraulic oscillator was first analyzed. The hydraulic oscillator has a pair of valves in periodical relative motion which transform the energy of the fluid flowing through the motive power parts into pressure pulses, which are in turn transferred to the oscillation sub. The oscillation sub drives the drilling tool in upward reciprocal motion along the axial line to convert static friction into dynamic friction at the bottom hole. This transformation effectively reduces drill friction resistance and improves WOB transfer effectiveness while having no impact on either measurement while drilling or screw drilling tool. The hydraulic oscillator was first put to pilot tests in Well Xinsha 21-28H of the Xinchang Gas Field, western Sichuan Basin. A weighting rod was fitted to the upper and lower parts of aΦ172 mm oscillator respectively to prevent axial line creepage of the drilling tool from posing the disruptive stress on it. As a result, the ROP of directional drilling and compound drilling was improved by 45.16% and 30.00% respectively. This was a very remarkable technical effect. The working capacity of the drill rig should be fully considered during the operation of this hydraulic oscillator with its potential to be maximized.