RN-Yuganskneftegas LLC is the biggest oil-and-gas production department in Rosneft Oil Company. RN-Yuganskneftegas was found at 1977 and operates 26 oilfields located in Western Siberia. Major part of Yuganskneftegas’ proved oil reserves are concentrated in the Priobskoye and Prirazlomnoye fields and these are green and strategical fields. In 2016 Well Construction Department initiated special project – well cycle reduction (for horizontal wells including wells with multi-stage frac). As a result of worldwide experience and searching of unstandardized decisions to reduce well timing Well construction department found new approach in designing. Our engineers found that extensive field data from wells drilled in the formation demonstrates possibility to optimize some operations by combining production section with horizontal one. The concept was named Dual-casing design. Combined interval should be drilled in one run. Once reaching TD tapered casing string should be run. In consequence of this approach – well timing of horizontal wells is 17 days Vs 30 days (per standard well).
During the pilot project, 12 wells were drilled with a consequent optimization of the solutions as experience gained. The results of the experimental work were recognized as successful and a decision was made to replicate the technology for drilling on different oilfield.
The article describes the features of drilling technology using optimized casing design with results and conclusions.
References
1. Giniatullin R.R., Kireev V.V., Pilipets E.Yu. et al., Two wells instead of one - reducing the timing of drilling. Difficult - Deeper - Faster (In Russ.), ROGTEC Rossiyskie neftegazovye tekhnologii, 2017, V. 48, pp. 14–22.
2. Gandzhumyan R.A., Kalinin A.G., Nikitin B.A., Inzhenernye raschety pri burenii glubokikh skvazhin (Engineering calculations for deep hole drilling), Moscow: Nedra Publ., 2000, 429 p.
3. Iogansen K.V., Sputnik burovika (Driller satellite), Moscow: Nedra, 1986, 294 p.
