The pipeline was in need of re-locating because a landslide in the region increased the risk of potential damage, so that remedial action was necessary to protect it and mitigate possible damage to the surrounding fragile environment.
The landslide resulted in the most ambitious rehabilitation operation in the pipeline’s history. Nearly a kilometre of 34 inch, Class 600 pipeline was affected by the landslide, which meant that around 2 km of it had to be re-routed.
TDW was called upon to carry out a hot-tap and plugging isolation intervention so that engineers could remove and replace the section of pipe threatened by the landslide, and the company provided engineering, design, and project management for the operation. The remit also included in-service welding supervision, welding inspection, pre-heating, and final non-destructive tests.
A total of 20 taps ranging from 2 inch to 34 inch had to be carried out, many of which were executed simultaneously to speed the process. The hot-tapping and isolation phase was performed between 20 September and 20 November 2014.
Using its standard STOPPLE® pipeline pressure intervention method to achieve the isolation, TDW made it possible to cut, plug, and safely isolate pressure from the sections without shutting them down. The operation also necessitated use of TDW’s LOCK-O-RING® Plus completion plugs, specially designed for the project.
After the lines were isolated, the contractor and the pipeline operator were able to carry out the relocation without serious disruption or negative impact upon the environment. The smooth handling and entirely safe execution of the hot-tapping and plugging phase also meant that the entire operation adhered to the tight schedule imposed by the operator.
“This was a huge job, which meant that we had to move masses of heavy equipment and specially designed hardware to a very difficult location in Turkey,” TDW’s Project Manager Volkan Simsek said.