Rosneft Developed a New Method for Selecting Casing Pipes
Specialists of the Ufa design institute of Rosneft developed a methodology for selecting casing pipes at fields with high content of corrosive components. The actual economic effect from the implementation of the innovation exceeded 3 million rubles per well.
Scientists analyzed more than 8,500 wells across 93 fields operated by Bashneft-Dobycha (part of Rosneft). Based on a comprehensive analysis of drilling and well operation experience, as well as laboratory studies, the specialists determined how hydrogen sulfide affects casing pipes made of carbon and low-alloy steels.
The institute developed a methodology for selecting pipes depending on the expected impact factors on the casing string. The methodology includes determining geological data and the degree of corrosion impact, calculating equivalent stresses of the casing string, and preparing a program for testing pipe samples.
Using this algorithm, Bashneft-Dobycha designs casing strings individually for each well, selecting pipes capable of withstanding the predicted concentrations of hydrogen sulfide. The new approach made it possible to identify wells where expensive alloy pipes can be replaced with carbon and low-alloy steel pipes while maintaining strength characteristics and operational safety. This makes it possible to optimize well construction costs by up to 40%.
Over the next 5 years, Bashneft-Dobycha plans to drill 79 wells using the new approach. The total economic effect from implementing the innovation will amount to 475 million rubles.
