气体钻井井内动力学分析

欠平衡钻井则是指利用自然条件或采取人工方法，在可以控制的条件下，使井筒内钻井流体压力低于地层压力，从而在井底形成负压差的过程。欠平衡钻井可以大幅度提高钻井速度，缩短建井周期．降低钻井成本。欠平衡钻井可以减轻或消除钻井液对油气层的伤害。良好的产层显示，有利于提高油气勘探成功率。欠平衡钻井技术以空气钻井的出现为标志，本文通过对空气钻井过程中井内气体稳定流动的分析，建立模型，以及过程推导，对空气钻井过程进行模拟。

Dynamic Analysis in Gas Well Drilling

Underbanlanced drilling is a process of forming negative pressure difference at the bottom of the well through which the pressure in the well bore is made lower than strata pressure by the effect of natural condition or artificial means, under controllable conditions. The process can enhance the drilling speed greatly; shorten the period of well establishment and lower drilling cost. Underbanlanced drilling can also lighten or eliminate the damage Io hydrocarbon reservoir that drilling fluid has done. Fine pay for- mation show that underbanlanced drilling can be help to the prospecting success ratio. The appearance of air sta dril ling is the sign of underbanlanced drilling technique. According to the analyzing of the floating air y in the well, this article set up a mathematic model to stimulate the process of air drilling.