CEMENTING MIXTURE Russian patent published in 2023 - IPC C09K8/467 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to cement mixtures intended for cementing casing strings and installing cement bridges due to the presence of weakly cemented rocks with a low hydraulic fracturing gradient. The cement mixture comprises, parts by weight: Portland cement type “ПЦТ I-50 29.99-39.98”; high-strength gypsum grade “ГВВС-19 24.98-34.98”; microspheres of the Granulite-2500 brand 24.95-29.99; condensed microsilica “МК-85 3.00-9.99”; retarder for setting of gypsum binders 0.01-0.10; Easy FLOW PC plasticizer 0.01-0.05. Microspheres of the Granulite-2500 brand have the following mineralogical composition, wt.%: glass 12-15, mullite 50-53, quartz 32-38. The setting retarder for gypsum binders EasyCitrate is trihydric sodium citrate. The Easy FLOW PC brand plasticizer is a mixture of polycarboxylate-based polymers.

EFFECT: accelerated process of hydration of the cement slurry, optimal strength of the stone, and improved quality of well casing.

1 cl, 1 tbl, 1 ex