GAS-CEMENT GROUTING MORTAR Russian patent published in 2015 - IPC C09K8/467 E21B33/138 

FIELD: oil and gas industry.

SUBSTANCE: gas-cement grouting mortar contains, wt. pt.: grouting cement 100, aluminium powder 0.1-0.6, mix of a phosphanol and nitrilothrymetil phosphonic acid 0.02-0.05 at their ratio wt. pt. 1:1.5, water 50-53.

EFFECT: improvement of quality of cementation of wells and efficiency of works on cementing of loose weakly cemented rocks of bottomhole zone of formation during repair of wells due to use of gas-cement grouting mortar with improved process properties due to the lowered dynamic shear stress, increase of time of the beginning of gas emission and increased strength of cement stone formed at curing.

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