No abstract

Авторское право 2015 г., Общество инженеров нефтегазовой промышленности Этот доклад был подготовлен для презентации на Каспийской Технической конференции и выставке SPE, 4 -6 ноября, 2015, Баку, Азербайджан.Данный доклад был выбран для проведения презентации Программным комитетом SPE по результатам экспертизы информации, содержащейся в представленном авторами реферате. Экспертиза содержания доклада Обществом инженеров нефтегазовой промышленности не выполнялась, и внесение исправлений и изменений является обязанностью авторов. Материал в том виде, в котором он представлен, не обязательно отражает точку зрения SPE, его должностных лиц или участников. Электронное копирование, распространение или хранение любой части данного доклада без предварительного письменного согласия SPE запрещается. Разрешение на воспроизведение в печатном виде распространяется только на реферат объемом не более 300 слов; при этом копировать иллюстрации не разрешается. Реферат должен содержать явно выраженную ссылку на авторское право SPE.

Stimulation is one of the initiatives to minimize production deferral. In Caspian Sea environment, stimulation job can be done through rig, which is not-so economical but provide more options to pump more volume; through simultaneous operation (from skid deck), which is economical but unfavorable in terms of space and opportunities generation; through simultaneous operation (from the vessel), which cater both advantages from skid deck and rig options earlier. A stimulation vessel project was initiated in order to deliver first of its kind in Caspian Sea of a vessel that capable pumping stimulation fluids into the well. A conceptual design on paper was exercised. To progress the project from papers to real work, a transformation in a way of working and deliver the project is needed. As this is the first in Caspian Sea, there are multi-interrelated factors affecting the project and most of them are unknown as nobody been through this process before, either operator and service companies. The project will be executed with an agile way of working to meet stakeholder's aspiration, by applying agile values and principles to transform the feel and performance of how we deliver the project. Learning from experience that applying agile practices can improve our focus on safety, operational risk by promoting technical assurance, iterative development and rapid learning cycles. This technique proves to safely deliver the first Stimulation Vessel in Caspian Sea.

Thru-tubing uphole re-completion is a workover technique aiming to re-complete the existing wellbore by temporary abandoning the lower producing zone and subsequently perforate upper layer. There are various techniques used to temporarily abandon the lower zone worldwide. Specific to Caspian Sea development, the temporarily abandonment will only be required to set an isolation plug. However, statistically speaking, success ratio of lower zone temporary abandonment, is quite low using current plugs set in different condition of completion. In addition, the risk of deploying balance cement plug also presents significant challenge due to interval limitation between top of the cement and new perforation interval. It is deemed necessary to find a fit-for purpose solution that provides a solution to the Caspian Sea environment plug and temporary abandonment strategy. A new plug technology, metal to metal system, was introduced to provide assurance isolating the lower zone prior to perforating new upper zone. Subsequently, a wireline deployed or pipe (tubing) conveyed perforation is not an attractive solution to thru-tubing up-hole recompletion technique. A new technology to perforate lively is selected from safety and economic point of view for this specific well. The perforation was done in underbalance condition with intelligent coiled tubing. The uphole re-completion (well delivery) performance was more attractive than other conventional uphole re-completion techniques. This paper will elaborate the success of recompletion techniques by deploying multiple new technologies in the Caspian Sea.

Concentric Coiled Tubing (CCT) was introduced in early 2014 to the Caspian Sea in the Azeri Chirag Gunashli field as a solution for sub-hydrostatic wells where sand cleanout techniques are not feasible with conventional methods because of circulation losses and poor offshore nitrogen logistics. A number of oil producer wells were successfully cleaned out using CCT prior to the technique being deployed on a water injector well for first time. This study considers the first CCT cleanout of a water injector well.In addition to cleaning sand from the well, the following main criteria were identified during the planning stage of the job; reduce wellbore contact friction inside the protective coated tubulars, minimize the number of CCT runs and fully displace heavy brine for a lighter friction reduced fluid. Job data collected during the initial runs was used for simulations with proprietary modeling software in an attempt to minimize pipe to pipe contact friction. A comparison based on the impact pressure at the nozzles with the available BHA's was also made from different scenarios simulated in order to best tackle the problem of any hard packed sand bridges in the well.This paper looks at how the above was achieved and also discusses the operational aspects of the job where proprietary BHA components and Coiled Tubing (CT) techniques were combined to break through a sand bridge described as the Љhardest fill ever experienced in the fieldЉ by the operator. A combination of intelligent CT, rotating jetting tool and a specialized switching cleanout sub was quickly mobilized alongside the planned CCT midway through the operation when the hard packed sand was discovered. Once the hard packed sand bridge had been completely removed, CCT and vacuuming technology were once again used across the perforated interval to establish a clean wellbore and injection into the reservoir.This paper is a case study and summarizes the main planning and operational steps of the successful cleanout job and provides some guidance for future operations.