Published on 27 September 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.
We completed the operation with strong involvement and collaboration from Wireline UK, Completions UK and Saltel France. It was a very challenging job to restore the integrity of a fiberglass-lined tubular.
The client identified a communication between the 5.5in [139.7mm] tubing and the 95/8in [244.4mm] casing. As a direct consequence, they temporarily suspended the gas injection, which caused a decrease in the field production rates. They also had to flare this gas.
First, we had to locate the leaks, then 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. The tubing leakage detection procedure identified two depths 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
We installed the first patch 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 we installed a second patch.
Then we pressure-tested the tubing with nitrogen at 660psi. The tubing leakage test showed there was no more communication between the tubing and the annulus.
The patch operations successfully restored the well integrity!
see also tubing repair