Schlumberger installed two 1-in Barrier Series gas lift valves in slim 4 1/2-in side pocket mandrels that had a special 6-in drift OD suitable for the 32-lbm/ft, 7-in liner. As a result, the gas injection depth was extended from 9,095 ft (just above the liner top) to 15,900 ft, where the well deviation is 69°, optimizing drawdown and production.
Each barrier valve incorporates a high-specification, metal-to-metal back check sealing module that has been developed and tested to meet strict quality, leak-rate, and performance standards, providing a robust seal between the tubing and the casing annulus. The check design uses enhanced geometry to minimize erosion during high-rate operations.
The improved design specifications increase performance and reliability of the gas lift system, minimizing well interventions.
Tubing-to-annulus communication is tested every 6 months. Since the initial installation in early 2016, no leakage has been detected.