Research on the application of self-excited oscillation rotary impact drilling technique

Abstract:

The self-excited vibration rotary percussion drilling technology can improve the rock breaking efficiency and the ROP.The application test in a test well located in the northern part of the Jizhong region were presented.The drilling diameter of the test well section is 215.9mm， and the BHA is PDC bit+ZJXC-178 self-excited vibration impact tool. The field application tests are carried out in two well sections， the test drilling section and the subsequent well section. Through a meticulous analysis and comparison of torque， bit usage， ROP and cuttings in the same well and adjacent well， the self-excited vibration rotary percussion drilling technology significantly improved the drilling speed， achieved the speed increase effect of up to 73.4%， and the footage of a single bit also increased by 48.2%.The effectiveness of this technology in improving drilling efficiency is verified. While ensuring the rock breaking cutting force of the bit， the sudden change of torque is effectively reduced， and the stick slip vibration of the bit is significantly inhibited， so as to achieve speed increase and protect the bit at the same time.

Key words:self excited oscillation;rotating impact;drilling tools;drilling speed up