DISCUSSION ON THEORY METHODOLOGY OF SUCTION-PULSE DRILLING TECHNIQUE

At present,since petroleum exploration development activities are going towards deep formation in china,formation encountered during drilling operation become harder and more complex with raised rock drillability,resulting in dramatic decrease of ROP(rate of penetration).The suction-pulse system not only generates suction pressure at the hole bottom,but also enhances jet energy to a certain degree.Therefore,this technique has unique advantage in improving ROP while drilling in deep formations.In this paper,how suction-pulse drilling enhances ROP is analyzed,and operating mechanism and characteristics of several kinds of representative suction-pulse tools are presented.Finally, ideas and direction for developing suction-pulse tools are put forward,which are of great significance in improving ROP and reducing cost whilie drilling in deep formation.