Experimental Investigation of Bit Vibration On Rotary Drilling Penetration Rate

This investigation evaluated the influence of bit vibration on penetration rate for laboratory rotary core drilling. Laboratory core drill was modified and instrumented to drill under conditions of constant Weight on Bit (WOB) and varying levels of axial vibration amplitudes. Experiments were conducted at 300 RPM and 600 RPM with no vibration and with 60 Hz of vibration at amplitudes of 0.09, 0.29 and 0.44mm. Results show that for WOB less than the founder point, the rate of penetration (ROP) increases proportionally to the amplitude of the vibration. Some tests show that ROP increase is greater near the peak of the ROP-WOB curve. Further laboratory experiments and numerical simulations are planned to investigate this vibration assisted rotary drilling technology.