Cutter layout optimization for reduction of lateral force on PDC bit using Kriging and particle swarm optimization methods

Polycrystalline diamond compact (PDC) bits are the dominant bit-types in oil and gas fields all over the world. Reducing the lateral force on PDC bits plays an important role in reducing drilling vibration and improving the service life of PDC bits. However, balancing the lateral force on PDC bit through the cutter layout design cannot precisely meet design requirements, especially after the bits wear. There is a large unbalanced lateral force when the bit is worn. In this paper, considering the bit wear, a cutter layout optimization model for reducing the lateral force is proposed. A models of wear and force for PDC cutters are built. Then, the optimal approach for lateral force on PDC bits is discussed, and an optimization case for a PDC bit is presented. The results show that the proposed zero point traversal (ZPT) algorithm can be used to calculate the unknown parameters in force and wear models of cutters. The proposed optimal approach has high computational efficiency, and can perform multi-parameter linkage adjustment. The optimization case shows that there is a significant reduction of the lateral force after cutter layout optimization. The stability of the bit is enhanced, and the service life of PDC bits is improved.