Optimization design of lateral force balance of PDC bits by genetic alg(?ithm

Key words:  genetic algorithm  PDC bit  lateral force  balance design

Abstract:

While optimizing PDC bits structures in terms of the lateral-force balance, the number of objectives to be optimized for a scatter-arranged bit is much more than that of a blade one, thus the searched scope for the optimum solution grows at exponential scale. In order to break the limit to optimization design of lateral force balance from bit structures, a new optimization design method by genetic algorithm was developed, which employed algorithms of proportional selection, single point crossover, uniform mutation and generation communication. A blade bit and a scatter one were optimized by this method. The ratio of lateral force to weight on bit is less than 1/1000. The convergence rate of the method is rapid, and its computational complexity is not affected by the number of blades or cutters too much.