Silicate Drilling Fluid System

On the basis of studying the silicate at home and abroad, setting out from fundamental property and silicate-based mud performance requisition ,through the preference of polymer and silicate modulus ,sets up silicate-based mud step by step.Comparatively overall appraisal are carried on the system established. Research reveals: the system have preferable rheology, filtrate and borehole wall build performance and favourable capacity to inhibit shale disperse and shale expanding.Pilot study are carried on mechanism of control and adjustment of rheology performance of silicate-based mud . Study and research method about the interaction of clay and silicate are put forward . Study shows: rheology performance of silicate-based mud are mainly controlled and adjusted by polymer . Clay mainly actes as reaction agent It has little influence on filtrate and inhibition capacity.The stabilization mechanism of borehole are studied and analyzed. Study shows: stable capacity of silicate-based mud mainly depends on silicate excellent inhibition itself .At the same time ,silicate can react with bivalent cation in stratum or liquid in hole and produces three-dimensional netlike gelatin and deposition. These production can stop or decrease the pass of pressure and covey of water, and keep stress state invariability as possible as it can , thus keeping borehole wall in steady state.