主权项 |
1. A method for designing a drill bit including cutting elements having a protector operable to control a depth of cut of the associated cutting element in a downhole formation, comprising:
(a) selecting, by a processor, a downhole drilling parameter; (b) determining, by the processor, a maximum rate of penetration (ROP) based on the downhole drilling parameter; (c) calculating, by the processor, maximum depth of cut for a cutting element based on the maximum ROP; (d) selecting, by the processor, an effective diameter and a back rake angle for the cutting element, and an effective diameter for the protector, wherein the protector is integrated in the cutting element; (e) calculating, by the processor, a protector length based on:
a difference between the effective diameter of the cutting element and the effective diameter of the protector,the back rake angle of the cutting element, andthe maximum depth of cut of the cutting element; (f) comparing, by the processor, the calculated protector length with an allowable range of protector lengths; and (g) if the calculated protector length is not in the allowable range of protector lengths, reselecting, by the processor the effective diameter of the cutting element, the back rake angle of the cutting element, or the effective diameter of the protector until the calculated protector length is in the allowable range of protector lengths. |