Drill String Vibration Attenuation and Its Effect on a Surface Oscillator Drilling System

The attenuation of acoustic vibrations was determined by measuring the decay of stress pulses induced in a drilling string. The relationship of attenuation to frequency was obtained by a Fourier analysis of the pulse after it had traveled various distances in the drill string. The attenuation coefficient was found to be sufficiently low to warrant consideration of drilling methods in which vibratory motion is transmitted from a surface vibrator to the bit by the drill string.