Successful Through Tubing Application of Wireless Real-Time Data Acquisition System in a Gas Producer

Abstract Objectives & Scope A new technology for wireless real-time downhole data monitoring was deployed in a brown field off the coast of Sarawak, offshore Malaysia, to monitor and analyze gas well and reservoir performance through one of the gas producers. The candidate was selected to better understand connectivity in a compartmentalized sector of the clastic reservoir. This innovative instrumentation involved a series of pressure and temperature gauges deployed on high-expansion gauge hangers (one main gauge with three repeaters) along the completion tubing via slickline. Once deployed, the downhole system is paired with a surface-mounted receiver and data logger. Methods, Procedures & Process This technology has effectively enabled real-time downhole data monitoring and analysis, which otherwise requires frequent wireline interventions or a workover to replace the Permanent Downhole Gauge (PDG) in a well fitted with one. The main objective of this wireless data acquisition solution is to enable real-time downhole data transmission, whereas conventional slickline-deployed gauges only support memory-recorded data over a limited timeframe. As such, the asset benefits from minimal production deferments caused by frequent interventions, and inadvertently minimizes operational, mechanical and well integrity risks. Additionally, downhole data acquisition programs are no longer constrained to wireline window availability, resulting in a more robust and continuous well and reservoir monitoring capacity, which is critical to ensure optimum reservoir performance over time. Results, Observations & Conclusions Success criteria were set against cost-benefit, battery life, consistency in data transmission via wireless communication, modification of data transmission frequency, and data suitability to support pressure transient analysis objectives. From the pilot run, the wireless solution consistently transmitted real-time downhole data (20% more data points than the target) and successfully delivered a data recovery rate of more than 97% during the pressure build-up test. Novel & Additive Information This paper describes the advantages, limitations and potential benefits of the sonic wireless monitoring system. Additionally, it will cover insights gained from the installation and utilization of the technology to serve as a valuable foundation for facilitating successful replications in the future.