Enhancing Well Integrity and Well Completion Flexibility with a Remotely Operated Multi-Cycle RFID Sub-Surface Isolation Valve

Abstract

Sub-surface isolation valves that form part of the well barrier envelope are required to have the most stringent qualification standards whilst also facilitating flexibility and functionality to complete the well safely and efficiently. By incorporating RFID technology into a hydraulically operated downhole ball valve, oil and gas wells can now be completed using remote electronic communication methods to actuate the barrier valve throughout the completion and well test phase.

The mechanical closure of the isolation valve, which is qualified to API 19v V1 CC classification, after any reservoir treatment can present significant well integrity problems should issues arise. To address this, an RFID microchip was to be incorporated into the work string as a contingency close trigger mechanism, should the shifting tool fail. Surface applied pressure cycles were sent to the isolation valve commanding it to re-open to allow well flow-back. Post well testing, an additional RFID microchip was deployed to the isolation valve to re-close it and form part of the well barrier envelope for P&A operations.

The well was completed and successfully tested by installing a set of completion equipment across the reservoir section. After the completion was installed the isolation valve was closed with a shifting tool isolating the reservoir section which allowed a safe well environment for running the upper completion. Having the electronic contingency option available significantly increases built-in contingency whilst reducing overall risk. With the reservoir isolated the upper completion was installed, pressure cycles were sent from surface to remotely trigger the valve to open. The short and specific sequence means that it is easily applied but hard to inadvertently trigger, therefore improving overall well completion flexibility and efficiency. The micro-hydraulic power technology on-board operates independently of hydrostatic pressure, ensuring that the valve opens regardless of the setting depth.

Once the well flow-back was successfully completed the valve was electronically closed by deploying an RFID microchip into the well for the final time, finalizing the P&A barrier envelope.

In conclusion, the combination of RFID on-demand multi-cycle technology with stringent sub-surface isolation valve qualification standards is now providing the industry with the integrity, flexibility, and reliability that it has long sought after, which adds up to a more robust and efficient well performance.

Shifting tools with built-in electronic triggers, advanced barrier valve qualification testing and high-performance sub-surface isolation valves are critical to well performance and safety within the oil and gas industry. This paper will focus on how these aspects were delivered to a super-major client to enable them to complete their well safely and efficiently.