The objective of writing this success story is to demonstrate how technology, in particular low cost solutions, are key to economically sustain and secure production from mature fields. Tubing Patch technology has been successfully utilized in Pakistan for the first time to restore the well integrity and saved huge CAPEX by avoiding expensive rig workover. Tubing-Annulus pressure suddenly increased in one of water disposal well (WDW). Annulus pressure varied directly with variations in Injection rates which were the clear evidence that tubing-annulus communication had been established and basic check ascertains that well had integrity issue. Being the only injector in area all production and processing of gas is majorly dependent on its injection reliability and integrity. After detailed in-house working it was decided to run diagnostic logging with spinner (quantitative) & temperature log (qualitative) to identify the leakage points precisely. All potential leakage paths (packer, tubing, tool joints) were considered while selecting the diagnostic techniques to have conclusive results. Based on diagnostic logging three leakage points were identified. Before proceeding for remedial measures to restore the well integrity, it was mandatory to check health of old carbon steel tubing string therefore it was planned to acquire corrosion log. Based on corrosion logging results, completion tubular was established in good condition which steered to install tubing patches best Techno-Economical solution across the leaks to restore well integrity instead of rig workover for re-completion. Consequently, three tubing patches, were successfully applied using wireline in water disposal well and integrity of well was restored. C-Annulus was pressure tested even after six months of installation and no pressure drop was observed during this interval.

The paper / presentation objective is to describe the achievement of the first gas lift well completed for multistage, hydraulically propped stimulation in a Romanian offshore field. The scope of the paper is to present the challenges and learnings associated with this well concept / design, engineering, modelling, equipment selection, yard testing, final design / program and offshore installation, operation, and results. Reservoir depletion modelling indicated artificial lift would be required as early as 6 months within initial well start up. In order to effectively optimise production from the well for a longer range of well life cycle, a multi-stage stimulation sandface completion was selected and plans were made to install gas lift equipment during initial completion installation, prior to rig release. To meet the concept requirements, risks were assessed and case histories were investigated / incorporated during the planning phase to ensure reliability of performing high-pressure stimulations through gas lift (dummy) valves. The material selection and specifications of the lower and upper completion equipment were defined considering:Artificial lift designReservoir characteristics, Casing size, High pressure stimulation, Life of well operations Equipment suitability and compatibility considerations resulted in a few equipment selection changes, requiring yard trials to define optimum pulling / running tool string components and configurations, which were then applied offshore. The final upper completion design consisted of gas lift mandrels (Gas lift dummies were replaced with gas lift valves following the HP stimulation), safety valve, permanent downhole pressure gauge and chemical injection mandrel. The lower completion consisted of hydraulic open hole packers, open hole anchor and open-close stimulation sleeves (all HP rated). Collaboration within the multi-discipline and with multiple service providers was vital in developing the final, tested design and implementation in the offshore well. The current design in the well is showing great benefits in terms of production (a higher rate than expected) and cost (initial completion includes gas lift equipment already available for future potential use). The concept proof is considered to be of great success for upcoming projects and is increasing the confidence of the operator to develop and approach the upcoming wells with multistage stimulation gas lift completions. This is the first well constructed in Romania that was hydraulically stimulated using proppant through an upper completion already having gas lift capability. A review of literature indicates this is an industry first. The success and communication of this well could provide benefit to the industry and could increase confidence when combining life-of-well requirements early in the well construction process.