全井钻头序列优化组合及参数优选

Optimized Combination of Bit Series and Optimized Parameter in Whole Well

钻井过程中，全井钻头类型的优化是一个多阶段决策问题。本文根据系统工程理论，生成全井钻头序列优化组合多阶段决策树，并构造出全井钻头动态规划的状态转移方程、指标函数、由最小化理论寻求最优树枝途径，以此获得全井钻头序列优化组合及工作参数优选，这是深井、超深井钻井，缩短钻（建）井周期，获得高钻速。

Optimization of bit types used in whole well drilling procedure is a multi-stage decision making. Basing on the systems engineering theory, this paper develops the multi-stage decision tree of optimized combination of whole-well bit series, the state conversion equation of whole-well bit dynamic programming, and index function. Furthermore, the minimization theory is used to seek the optimized tree path, through which the whole-well bit series optimized combination and the optimized working parameter are obtained, This is an essential path to achieve short drilling period, high drilling rate, low cost in drilling deep or superdeep well.