气藏水平井钻井液密度附加值研究  

Determination of the Additional Mud Density of Drilling Fluids for Horizontal Wells in Gas Reservoir

作　　者：齐明明[1] 李相方[1] 鄢捷年[1] 

机构地区：[1]中国石油大学

出　　处：《钻井液与完井液》2007年第3期10-11,19,共3页Drilling Fluid & Completion Fluid

摘　　要：针对气藏特别是高产气藏水平井钻井过程中钻井液密度附加值是否需要提高的问题,在分析研究了气体侵入井筒后井底压力降低情况和钻井液密度变化对侵入井筒气体上升速度的影响后,从储层类型、井的类别、井型、井深等多方面探讨了气藏水平井钻井液密度附加值的确定方法和影响因素。结果表明,气藏过平衡钻井过程中是否会发生井喷主要取决于对地层压力的预测准确与否,而不在于钻井液密度附加值的大小,因此没有必要在气藏钻水平井就增大钻井液密度附加值;对于深井、超深井,钻井液密度的增加会引起气体上升速度的加快,反而缩短井控反应时间,因此钻井液密度附加值的确定应综合考虑储层类型、井的类别、井型、井深等多方面的因素。An analysis as to the bottom hole pressure drawdown caused by the gas kick and the change of mud density after gas kick was done in this paper.A method of determining the additional mud density for gas well drilling fluids was proposed based on the analyses of the reservoir types,well types and well depths.Also discussed in this paper was the influencing factor concerning the additional mud density.It is shown that the prevention of well blowout in over balanced drilling in gas reservoir is governed primarily by the accurate predict of formation pressures,but not by whether an additional mud density is applied.Then it is not necessary to increase mud densities in drilling horizontal wells in gas reservoirs.For deep and ultra-deep wells,increase in mud density will cause an accelerated ascending of the gas enter into the mud,thus leading to a shorter preparing time for well control.It is concluded that the additional mud density should be applied after taking into account factors such as the type of reservoirs,well types,and well depth etc.

关 键 词：气藏水平井 钻井液 密度附加值 

分 类 号：TE254[石油与天然气工程—油气井工程]