Franca, LF & Mahjoob, A 2008, 'Drilling Action of Roller-Cone Bits — Modelling and Experimental Validation', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium
, Australian Centre for Geomechanics, Perth, pp. 625-632.
This paper presents a model of the drilling response of roller-cone bits with experimental validation. First, a set of relations between the weight-on-bit (W), the torque-on-bit (T), the rate of penetration (V), and the angular velocity (, are established using the same methodology as that applied for polycrystalline diamond compacts (PDC) bits presented by Detournay and Defourny (1992) and later complemented by Detournay et al. (2008). Then, a series of laboratory tests at atmospheric pressure with roller-cone bits reported by Karasawa et al. (2002) is used to validate the proposed model. Although the results have been obtained on a limited series of rocks, they are very encouraging in regard to the potential use of this formulation to investigate the drilling action of roller-cone bits. Furthermore, it is observed that the values identified for the intrinsic specific energy are close to the respective uniaxial compressive strength (USC). This result suggests therefore that the intrinsic specific energy and uniaxial compressive strength are correlated in tests conducted at atmospheric pressure.
Burgess, T.M. and Lesso, W.G. (1985) Measuring the Wear of Milled Tooth Bits Using MWD Torque and Weight-on-bit, Society of Petroleum Engineers, SPE-13475, pp. 453–462.
Cunningham, R. (1967) Calculation of Torque and Horsepower, Technical Session of the Rotary drilling Committee, American Association of Oilwell Drilling Contractors.
Detournay, E. and Defourny, P. (1992) A Phenomenological Model for the Drilling Action of Drag Bits, Int. J. Rock Mech. Min. Sci. and Geomech. Abstr., Vol. 29, No. 1, pp. 12–23.
Detournay, E., Richard, T. and Shepherd, M. (2008) Drilling Response of Drag Bits: Theory and Experiment, Int. J. Rock Mech. Min. Sci. (in press).
Hoberock, L.L. and Bratcher, G.J. (1996) A New Approach for Determining In-Situ Rock Strength While Drilling, Journal of Energy Resources Technology, Vol. 118, pp. 249–255.
Johnson, K.L. (1985) Contact Mechanics, Cambridge University Press, pp. 107–152.
Karasawa, H., Ohno, T., Kosugi, M. and Rowley, J.C. (2002) Methods to Estimate the Rock Strength and Tooth Wear While Drilling with Roller-Bits, Part 1: Milled-Tooth Bits, ASME J. Energy Resour. Technol., 124, pp. 125–132.
Maurer, W.C. (1962) The Perfect-Cleaning Theory of Rotary Drilling, Journal of Petroleum Technology, pp. 1270–1274.
Pessier, R.C. and Fear, M.J. (1992) Quantifying Common Drilling Problems with Mechanical Specific Energy and Bit-Specific Coefficient of Sliding Friction, Journal of Petroleum Technology SPE-24584, pp. 373–388.
Richard, T., Dagrain, F. and Detournay, E. (2008) Determination of Rock Strength Properties from Scratching Tests, Int. J. Rock Mech. Min. Sci. (in preparation).
Sheppard, M. and Lesage, M. (1988) The Forces at the Teeth of a Drilling Roller Cone Bit: Theory and Experiment, Society of Petroleum Engineers, SPE-18042, pp. 253–260.
Teale, R. (1965) The concept of Specific Energy in Rock Drilling, Int. J. Rock Mech. Min. Sci., Vol. 2, Pergamon Press, pp. 57–73.
Warren, T.M. (1984) Factors Affecting Torque for a Roller Cone Bit, Journal of Petroleum Technology SPE-11994, pp. 1500–1510.