COMPOSITION FOR CREATION OF BOREHOLE FILTER Russian patent published in 2015 - IPC E21B43/08 C09K8/467 

FIELD: oil and gas industry.

SUBSTANCE: composition for creation of the borehole filter including the binder - Portland cement, fibrous filler - fibre, it also contains Microdur, high-soluble salt - carbonic potassium (potash) having inclusions of natural isotopes, retarder - boric acid with neutron-absorbing properties, tempered on saturated solution of the named salt, at the following ratio of ingredients, wt %: binder - Portland cement 43.79-45.77, microdur 4.57-7.31, fibrous filler - polymeric polypropylene fibre with a diameter 17-21 mcm and 12 mm long 0.23-0.37, high-soluble salt - carbonic potassium (potash) K₂CO₃ 2.29-2.92, retarder - boric acid H₃BO₃ 1.37-1.82, saturated solution of carbonic potassium K₂CO₃ γ = 1.45 g/cm³ 43.79-45.77.

EFFECT: development of composition of concrete mix for obtaining of fireproof coating with high heat-resistance, having the improved physico-mechanical characteristics and allowing to increase the limit of fire resistance of ferroconcrete structures.

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