METHOD FOR STRING CEMENTING IN WELL USING CEMENT MORTAR WITH EROSION PROPERTIES Russian patent published in 2010 - IPC E21B33/14 

FIELD: oil and gas production.

SUBSTANCE: invention relates to the field of well building and will find application in oil or gas well casing, and also in repair works related to cementing. Method provides for serial pumping of washing spacer fluid and three portions of cement mortar, the third of which is for productive zone. At the same time the first portion pumped following spacer fluid is cement mortar with erosion properties prepared from at least 5 tons of oil-well portland cement mixed with abrasive material in the ratio of 100:8 in weight and with density of 1.64 g/cm³, where abrasive material is represented by quartz sand with average grain size of 0.28-1.0 mm. Method application provides for maximum removal of drilling fluid remains from walls of string and well, as well as for efficient damage of adhesion film and filtration crust of clayey solution.

EFFECT: increased intensity of string cement stone contact with environment, and accordingly, high-quality isolation of beds.

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