Optimization And Application Of Drilling Fluid For Shuangtaizi Area Of Liaohe Oilfield

Block Shuangtaizi is a key block in Liaohe oilfield,of which the shale formation in Don gying group and Shahejie group is characterized by large formation thickness,complex rock components,high instability and large burial depth.During drilling process,loss of shale for mation stability often occurs leading to hole shrinkage and collapse and resulting in long time of trouble handling such as redressing or tool jamming.A detail analysis of the shale rock co mponents in Block Shuangtaizi was made combining with real engineering information.And a compatible drilling fluid system and associated agents was found according to the real form ation rock characteristics.During the process,a series of laborary tests were carried out for ev aluation of drilling fluid and agent performance,and at last the optimized KCl polymer drillin g fluid system and related agents were chosen,partly considerinbg its field performance,whic h could hold good hole stability and owns strong high temperature resistance.And the drilling fluid design was optimized according to the field operation requirement.The chosen KCl dril ling fluid system was successfully applied in Well Shuangxin-1 resulting in good hole stabilit y,no existence of downhole complexity,a reduction of drilling period and good composite ec onomic results.