Analysis of the Cutting Features of the Damaged Rock by Shock Disturbance
نویسنده
چکیده
Abstract: This article aims to study the effects of shock-disturbed cracks on the cutting features of cone bits. By utilizing the Walsh’s model, a crack model was established for the damaged rock surrounding the induced hole, the intrusive coefficient of the cone bit was derived, and the drilling rate equation around the induced hole was formulated. The effects of crack density and disturbance frequency on elastic modulus, intrusive coefficient, and cutting force were studied. With an increase in crack density, both the effective elastic modulus and the intrusive coefficient decreased. Under a certain range of internal friction angle, with an increase in crack density, the drilling rate increased. Under a certain axial load, as the disturbance frequency increased, the cutting force of one-cone bits decreased.
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