Full-phase optimization of PDC bit cutter layout to reduce lateral force based on zoning method

Balancing lateral force is essential to reduce bit vibrations and prolong bit service life. During the process of cutting, the instantaneous cutting situation is governed by the previous blades cutting. This paper introduces a notion called "zoning method" based on the cutting geometry of bit-rock interface, which is dedicated to distinguishing different phases of cutting. Furthermore, a full-phase optimization model is developed to optimize cutter layout for minimizing the lateral force in each cutting phase, the NSGA-II is used to solve for the Pareto-optimal solutions, and the fuzzy comprehensive evaluation method is used to select the optimal solution. Finally, a case study of full-phase optimization of PDC bit cutter layout is conducted to highlight the advantage of the zoning method. The case study results show that the lateral force is reduced significantly in each cutting phase by using zoning method, which can help to achieve the real lateral force balance of PDC bit.