Blocking, viscoelastic solutions

Special fluids for blocking of high-permeability formations or formation with abnormally low formational pressure.Drilling fluids are prepared on the basis of aqueous solutions of salts in order to ensure necessary density within the range from 1000 kg/m3 to 1800 kg/m3 with adding of mineral and organic acid-soluble fillers. Blocking fluids with use of special fillers: 

• On the basis of KCl salts for pressure differential up to 10 MPa;
• On the basis of KCl salts for pressure differential up to 20 MPa;
• On the basis of CaCl2 salts for pressure differential up to 30 MPa;
• On the basis of CaCl2 salts for pressure differential over 30 MPa.