INSULATION MATERIAL-HYDRAULIC SEAL Russian patent published in 2002 - IPC

FIELD: oil and gas production, materials used to fix and insulate casing string in well. SUBSTANCE: insulation material-hydraulic seal includes waste drilling fluid of certain density and polyacrylamide -1020 with addition of ferrochroumlignosulfonate, corrosion inhibitors and neutralizers of chemical agents (correxit 7798, synthetic iron oxide 7, carboxylmethylcellolose) with following ratio of components, mas.%: waste drilling fluid: polyacrylamide -1020, 0.01-0.1; ferrochroumlignosulfonate, 0.004-0.1; corrosion inhibitors and neutralizers of chemical agents, 0.01-1.0; carboxylmethylcellulose, 0.01-1.5. Amount of waste drilling fluid with other components depends on mineralogical composition of rock passed by well shaft. Proposed insulation material can include additionally filling agent (bentonite or chalk or gypsum) which ensures backpressure on productive pool in quantity of lost density of drilling fluid when it was added with said liquid components. EFFECT: improved structural parameters of hydraulic seal, of its physical, chemical, thermal and anticorrosive properties. 1 cl