Subsurface Safety Valve Control Line Leak Resolution Using a Pressure Activated Sealant Technology

Abstract The integrity of critical barriers deteriorates over the life of a well. To support continuous oil and gas production, identified integrity issue needs to be properly managed and addressed. Most integrity issues are associated with leaks around downhole completion equipment where the tubing retrievable surface controlled sub-surface safety valve (TR-SCSSV) is a critical component. The TR-SCSSV function is achieved by applying hydraulic fluid pressure through a control line (CL) to open it, or bleeding same fluid to close the valve. From the foregoing, the potential for leaks exists around CL termination or connection points, tubing hanger body and/or neck seals and SCSSV hydraulic system seals. When this occurs, the SCSSV integrity is compromised resulting in failure to open the SCSSV flapper. Such SCSSV failure is usually restored with the conventional method of a rig workover to pull and replace tubing with a new SCSSV at a considerable cost. This paper discusses an in-situ, safe and cost-effective solution, leveraging the pressure-activated sealant technology workflow that was developed and successfully applied to candidate wells with SCSSV CL leaks. It outlines the capabilities of the Seal-Tite technology and the cost-saving production restorations achieved during a campaign in some Mobil Producing Nigeria (MPN) field locations. The overall objective was to diagnose and seal CL leaks to restore integrity, without clogging the hydraulic system or flow path to the safety valve.