| 摘要 |
The present invention relates to the composition of a saline polymeric fluid for drilling oil wells in depressurized areas or areas with a low fracture gradient, with directional, deflected and horizontal characteristics, in areas that are productive, depleted, fractured, have circulation loss, bore instability and where there are problems with cleaning the well, characterized in that said composition is based on sea water as continuous phase and in that the formulation thereof comprises an alkalinizing agent and pH regulators, preferably caustic soda; a calcium-sequestering agent, preferably sodium carbonate (soda ash), a high-purity biopolymer, preferably xanthan gum, a filtrate reducer and mechanical inhibitor, preferably polyanionic cellulose with a greater substitution level, which makes it possible to obtain an excellent mud cake; an inhibiting salt, preferably potassium chloride, and an amine- or glycol-based clay inhibitor. The invention also comprises a reinforcing component for the quality of the filtrate, which comprises a starch modified for high temperature that allows the thermal effect to be controlled. |
