FLUIDS FOR REDUCTION OF HYDRODYNAMIC FRICTION Russian patent published in 2012 - IPC C09K8/68 E21B43/22 E21B43/267 

FIELD: oil-and-gas production.

SUBSTANCE: proposed fluid to be used in oil fields comprises: 0.001 wt % to 0.5 wt % of surfactant reducing drag and at least one activator of drag reduction selected from the following group: polymer drag reduction activators selected from the group comprising low-molecular water-soluble polymers and copolymers containing at least one aromatic cycle, or their mixes with monomer drag reduction activator. Note here that said fluid allows drag reduction percentage making at least 20%. Proposed method of regulating clay swell in brine-free well shaft comprises: preparing above fluid suspending reduction agent and injecting it into well shaft. Method of processing in-situ in oil filed whereat said suspending reduction agent is prepared, injected into well shaft to reach drag reduction percentage equal to at least 20%. Invention is developed in dependent claims.

EFFECT: improved viscosity and power to suspend solid substances at low surfactant concentrations.

20 cl, 33 ex, 4 tbl, 36 dwg