The upper part of the geological section of the deposits of Eastern Siberia is composed of permafrost, weakly cemented rocks and karst cave formations. During the drilling of such intervals, a number of complications arise associated with the absorption of flushing and cementing fluids, sloughs and collapses of well walls. Drilling of complicated sections of the wellbore is carried out using a complex design (additional direction with a diameter of 426 mm) and aerated liquid. The history of well construction under these conditions has shown the low efficiency of using various technological and technical solutions in terms of high-quality fastening of casing columns (conductors). Even the use of quick-setting compounds did not give positive results when cementing well casing strings. Based on the results of an analysis of standard technologies for direct and counter cementing of conductors in conditions of complete absorption using cementing materials based on Portland cement in wells of fields in Eastern Siberia and taking into account the positive experience of cementing wells in permafrost conditions with gypsum cement mixtures, a comprehensive technological approach to fastening casing strings was developed. This solution involves direct and counter cementing using an additional plugging composition. As a result of the application of the developed technology, positive results were obtained for fastening casing columns in complicated conditions and intellectual property rights were issued.
References
1. Gladkov E.A., Shiribon A.A, Karpova E.G., Ways solutions of the problems encountered during drilling in Eastern Siberia (In Russ.), Burenie i neft', 2015, no. 4, pp. 42–45.
2. Gorskiy A.T., Formation of cement stone under conditions of simultaneous exposure to positive and negative temperatures (In Russ.), Neft' i gaz Tyumeni, 1969,
no. 3, pp. 22–26.
3. Ugol'nikov Yu.S., Complex technological solutions to isolate intervals of the acquisitions process fluids (In Russ.), SPE-181950-MS, 2016,
DOI: https://doi.org/10.2118/181950-MS
4. Bykov V.V., Paleev S.A., Medvedev Yu.V., Improving the quality of cementing lines and conductors in the conditions of permafrost in the fields in Eastern Siberia
(In Russ.), SPE-181937-MS, 2016, DOI: https://doi.org/10.2118/181937-MS
5. Patent RU2792128C1, Method for cementing the conductor, a technical column during the construction of wells, Inventors: Akhmetzyanov R.R., Bykov V.V.,
Zakharenkov A.V., Paleev S.A.
