基于油基钻井液提高钻速的原理与方法

结合通用钻速方程和油基钻井液的特点,分析了油基钻井液对钻速正反两方面的影响,指出了影响机械钻速的主要因素是地层岩石特性,其次是井型和钻井液性能.提高机械钻速的主要途径包括钻头的合理选型、钻进技术参数的合理优化,以及钻井液配方与性能优化.通过调整钻井液配方与性能,使其能够有效清洁钻头、改变井底岩石的润湿性、大幅度提高钻井液的极压润滑性；向钻井液中加入中性润湿剂改变微裂隙表面润湿性；加入抗高温的油溶性高分子增黏提切剂代替有机土、氧化沥青等胶体颗粒,以便降低微米、亚微米颗粒含量,提高剪切稀释性和携岩效率,从而提高机械钻速.

Research on Mechanism and Methods of Improving ROPfor Oil-based Drilling Fluid

The positive and adverse influences of oil-based drilling fluid on ROP are analyzed with the general equationfor drilling rate in terms of the properties of oil-based drilling fluid. It indicates that the formation lithology superior tothe well type and drilling fluid exerts the main influence on ROP. The optimum type of drilling bit and optimization ofdrilling parameters play a more important role in improving ROP than the formulation and performances of drilling fluid.Through regulating the composition of drilling fluid, cleaning bits, alternating wettability of bottom-hole rock, improvingthe extreme pressure lubricity, adding neutral wetting agent, mixing high temperature stability oil-soluble macromoleculeagent to replace organic clay and oxidized asphalt, reducing the contents of micron and submicron particles, modifying shearthinning behavior and increasing efficiency of carrying cuttings to help improving the ROP effectively.