Creates a positive pressure to interstitial pressure;
- transfers hydraulic power to the bottom hole motor and chisel;
- provides a high quality producing formation exposing;
- ensures lubricating and corrosion-inhibiting effect on drilling tools;
- cools and lubricates a chisel;
- prevents drilling troubles (sticking of drilling tools and intermediate casing, circulation loss, oil and gas shows, etc.);
- reduces friction factor;
- ensures environment protection.
