自激振荡式旋转冲击钻井工具在胜利油田的应用

摘要 :自激振荡式旋转冲击钻井工具安装于钻头上部 , 钻井液高速流经自激振荡器，形成水力脉冲作用于冲击传递杆，产生低幅高频机械冲击力传递至钻头，提高钻头破岩效果；所产生的水力脉冲再向下传递，经钻头水眼喷出形成脉冲射流，改善井底流场，提高井底净化和清岩效率，同时井底瞬时负压脉冲产生局部瞬时欠平衡，改变井底岩面破岩应力状态，可明显提高机械钻速。在胜利油田沙三和沙四段地层进行了钻井试验，无论是牙轮钻头还是 PDC钻头都有明显的提速效果，试验井段的机械钻速都提高了 30%以上，可成为钻井提速的新途径。

Application of self-oscillating rotary percussion drilling tools in Shengli Oilfield

The self-oscillating rotary percussion drilling tools are set above the bit.The drilling fluid flows through the self-oscillator with high speed and hydraulic pulse is formed and is imposed on the percussion transmission rod,following with the generation of low amplitude but high frequency mechanical shock power,which can be passed to the bit and improve the rock breaking efficiency.The generated hydraulic pulse is transmitted down further and blown off through bit ports,which will form pulse jet flow and can improve the downhole flowing domain and the efficiency of downhole cleaning.Meanwhile,the instant negative pressure pulse generates local instant underbalance and changes the rock breaking stress status of downhole rock surface,which improves the rate of penetration significantly.The system is tested in Sha-3 and Sha-4 formations in Shengli Oilfield.The results show the rate of penetration is significantly increased no matter with cone bit or PDC bit,and the rate of penetration of all the tested formation sections increases more than 30%,so the technique could be a novel method of increasing the rate of penetration.