VISCOELASTIC COMPOSITION FOR INSULATING OPERATIONS IN WELLS Russian patent published in 2009 - IPC C09K8/04 E21B33/138 

FIELD: oil and gas industry, chemistry.

SUBSTANCE: inventions refers to oil and gas industry, particularly to viscoelastic compositions for insulating operations in wells, which can be implemented for eliminating gas events in drill string casing annulue, for insulating permeable reservoirs at boring and repair of wells, for repeated pressurising threaded connections of casing string, for separation of fluid flows and at other repair works. Viscoelastic compoisition for insulating operations in wells consists of polyacrylamide, of binding agent - chromium nitrate, of gel formation regulator - sulfanic acid and additionally Monasil, of a phytogenous filler - organic mineral reagent "APTON-RS" and water at the following ratio of components, wt %: Polyacrylamide 1.4-1.9; Chromium nitrate 0.25-0.32; Sulfanic acid 1.5-3.1, Monasil 0.11-0.23; Organic mineral reagent "APTON-RS" 5-11, Water - the rest.

EFFECT: improved process properties of viscoelastic composition owing to controlled time of gel forming, to upgraded plastic strength and adhesion to metal of pipes and to reservoir rock, increased efficiency of insulating operations in wells.

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