Sergey Samyshkin Acting Drilling Dept. Director, TNK-Uvat
Vladimir Malov, Regional Supervising Manager, Drilling Dept., TNK-Uvat
In 2010, TNK-Uvat demonstrated the best performance among the Upstream’s subsidiaries. Thus, almost 500,000 t were produced above the plan, which came as a natural outcome of the introduction of innovations and the efficient cooperation of all teams in the subsidiary, including the Drilling Dept. This year, the scope of new well construction in Uvat will increase nearly twofold, and more new technologies will be introduced.
Full-scale development drilling in Uvat group of fields started back in 2007; to date, over 230 wells have been built, and the total footage is nearing 800,000 m (last year alone, the footage reached 256,000 m and 69 wells were commissioned). To maximize drilling efficiency in Uvat, quite a few innovative technologies were successfully tested and implemented, including advance conductor driving, new bit designs, high-torque downhole motors, MWD (measurement while drilling) tools with electromagnetic communication channels, logging while drilling (LWD), etc. As a result, rates of penetration have increased dramatically: in 2007 it took 10.27 days to drill 1,000 m, while in 1Q 2011 it became a matter of five days only.
Apart from standard directional wells, nine horizontal wells and two dual completion wells were drilled in Uvat. The successful horizontal drilling was one of the main factors underlying TNK-Uvat’s performance improvement in 2010: the flow rates of these wells exceeded the drillers’ expectations and reached 250 tpd to 550 tpd. Following this success TNK-Uvat reviewed and expanded its horizontal drilling program.
The business plan for 2010 was exceeded due to one more factor: the first ever frac program in Uvat. Fracs greatly increased productivity of complex low-permeability reservoirs and are currently being widely performed in Urna, Ust-Teguss and Tyamkinskoye fields.
Super Pipes for Super Well Pads
The approved Uvat development plan provides for unconventional drilling of the well pattern from super well pads per 48 wells (see “Advanced Drilling Technology for Advanced Uvat Fields”, Innovator #37). This solution provided quite a few organizational, economic and environmental benefits,but on the other hand significantly complicated the drilling technology. In particular, the new approach stipulated construction of wells with ever greater step-outs, which did not exceed 1,500 m at the launch of the project and have since increased up to 3,600 m – and this is not the limit.
This additionally complicated the drilling process through worse cuttings recovery and poorer wellbore stability. To improve the situation, it was decided in 2011 to test Hydroclean drill pipes manufactured by VAM Drilling, France. All the necessary equipment has already been purchased, and a pilot project to test it in wells with step-outs over 3,600 m will be launched in May in Ust-Teguss. This technology is expected to increase drilling efficiency by 5 percent to 7 percent.
Another innovation to be introduced in 2011 is Landmark software package. The pilot project has been running at TNK-Uvat Drilling Dept. since March and, if successful, it will be rolled out in all TNK-BP’s target subsidiaries. Landmark is an integrated solution for data management throughout the entire well life cycle that enables data acquisition (including near-real time data acquisition) and subsequent data analysis. The software functions include planning and reporting on the operations completed, wells history tracking, cost planning and tracking, and skills gaining and application. Anton Duder, Supervisor in TNK-Uvat Drilling Dept., contributes immensely to Landmark project implementation.
New Contractors and New Records
To satisfy the expansion of TNK-Uvat’s drilling program and encourage competitiveness, some new contractors have come to work in Uvat: Eriell (drilling), M-I SWACO (muds) and Baker Hughes (directional drilling). Eriell’s ZJ-70 DBS drilling rig has been by now successfully assembled on Well Pad #2 in Tyamkinskoye field. Moreover, KCA Deutag, TNK-Uvat’s long-standing contractor, has mobilized a T-500 rig in addition to the four operating rigs. Both new rigs allow for all state-of-the-art engineering solutions in drilling.
The rig fleet upgrade and the contracting of new vendors has resulted in new records in drilling rates. When the surface casing of Well #345 in Tyamkinskoye field was being drilled Uvat’s record average penetration rate of 118 m per hour was reached, and the construction of Well #2625 in Ust-Teguss recorded TNK-BP’s best daily penetration rate: 1,051 m.
As compared to 2010, the drilling efficiency in 2011 has increased by 17.28 percent for horizontal wells and by 12.52 percent for directional wells. Every rig working in Uvat has shown progress, but special tribute is to be paid to the T-503 rig crew supervised by Vyacheslav Koblov and Nikolay Kokovin who improved their performance by 14.5 percent compared to 2010.
Room for Achievements
TNK-Uvat’s exploration drilling program for 2011 provides for construction of 16 wells, five of which have already been drilled and another five are being currently drilled and tested. Upon completion of these operations, it can be possible to launch development drilling in 2012-2014 in Radonezhskoye and Yuzhno-Petyogskoye fields: the total oil in place in both exceeds 70 mln t and recoverable reserves are about 20 mln t.
In view of coming operations in the new fields, TNK-Uvat Drilling Dept. will have to significantly expand the range of drilling and service contractors engaged, which will bring about a positive competitive environment and, in the long run, will further enhance drilling efficiency in Uvat.