DuraLift Anti-Scale Valve
On the Norwegian sector of the North Sea, barrier qualified gas lift valves often form an integral part of the well barrier envelope and as such they are routinely tested to ensure well integrity. On one such well after performing for one year, a gas lift valve failed the integrity test and was pulled from the well. Upon inspection of the valve scale deposits were discovered. PTC’s DuraliftTM anti-scale valve was subsequently run into the well and has been passing integrity tests for the last two years.
An existing platform well in the Norwegian sector of the North Sea comprised of:
• 3 x gas lift mandrels in 5 ½" tubing inside 9 5/8" Casing
• 2 x dummy valves and 1 operating valve
The well produced successfully and the gas lift valve performed as expected for a period one year, before failing an integrity test. The valve was pulled and although scaling issues were not expected in this particular well, upon inspection of the valve scale, deposits were discovered and verified by lab analysis. The configuration of the well did not allow for the injection of scale inhibitors.
PTC’s DuraLiftTM anti-scale valve was installed in the well and has consistently passed well integrity tests for the last two years.
Significant costs savings were realized as yearly interventions were no longer necessary to keep the well performing. In this particular case despite the fact that well interventions were preformed offline (not requiring a rig) savings of + 75KUSD/year were reported.