Published on 27 septembre 2018
A tubing leak successfully isolated and a parted section covered successfully with Saltel Patch
Saltel Industries just met another success offshore UK, with the installation of two 5.5in [139.7mm] internal gas-tight tubing patches in a 17 year-old gas injector well.
The client is extremely happy with Schlumberger’s solution. They really appreciated the whole process from logging to patch design, and installation.
The operation was completed with strong involvement and collaboration from Wireline UK, Completions UK and Saltel France. This was a very challenging job to restore the integrity of a fiberglass lined tubular.
A communication was identified between the 5.5in [139.7mm] tubing and the 95/8in [244.4mm] casing. As a direct consequence, gas injection was temporarily suspended, which caused a decrease in the field production rates. Besides, gas had to be flared.
First, we had to locate the leaks, then to restore the tubing integrity.
Combining MultiFinger Imaging Tool (PMIT) with Distributed Temperature Sensing by Fiber-Optic (DTS) led to identifying depths of possible leaks throughout the 5.5in fiberglass lined tubing. Two depths were identified for patch installation:
- 376 ft [114.6m] : leak confirmed due to temperature variation on DTS
- 106 ft [32.3m] : leak suspected due to unexplained diameter increase observed on PMIT
A first patch was set to seal off the leak at 376 ft, but the tubing pressure test failed. A camera run confirmed that the tubing was parted at 106ft, and a second patch was installed.
The tubing was then pressure-tested with nitrogen at 660psi: there was no more communication between the tubing and the annulus.
Well integrity was successfully restored!