用于含砾石且软硬交错地层的新型PDC钻头设计

The design of PDC bit for multi-interbedded and gravel formation

PDC钻头用于软到中硬的均质地层钻进具有钻速高、寿命长等特点 ,但不适合含砾石地层和软硬交错地层。鉴于此 ,针对含有砾石和软硬交错地层的特点 ,提出了混合切削结构设计 ,并制造了新型PDC钻头 ,在含砾石的地层和软硬交错地层中取得了较好的使用效果。混合切削结构增强了PDC钻头的使用可靠性和穿越砾石层的能力 ,减轻了切削齿的先期损坏。用 1只新型PDC钻头可以钻成 1口 2 5 0 0m以浅的中深井 ,减少了起下钻次数 ,缩短了建井周期。

PDC bits have been used to drill the homogeneous formation from soft to medium-hard, but they are not suitable for drilling in gravel and multi-interbedded formation. Therefore a PDC bit with new compound cutting structure is developed in the light of the characteristics of gravel formation and soft-hard interbedded formation. The new bit was used in Shengli Oilfield, and good results has been achieved. With the new cutting structure, the cutter's early damage is reduced or even eliminated, and the service life of the bit is obviously improved.