Nord Stream receives 12 t custom-designed tool

TDW Offshore Services AS (TDW) has announced it has successfully designed and built a customised 48 in. SmartPlug^® pipeline pressure isolation tool for Nord Stream AG. Weighing approximately 12 t, it is the largest SmartPlug tool ever produced.

Nord Stream retained TDW to assist in developing contingency solutions for pipelay, pressure testing and planned future maintenance of the Nord Stream gas pipelines. Upon completion, the two 48 in. pipelines will extend 758 miles (approximately 1220 km) from Russia through the Baltic Sea to Germany.

The company carried out a series of pre-engineering studies before finalising the design. The SmartPlug tool was designed, built and rigorously tested by TDW at its global headquarters in Stavanger, Norway. The new isolation tool will be used to safely isolate pipeline pressure during scheduled pipeline maintenance and potential valve change-outs. It is currently Type Approved by Det Norske Veritas for a maximum operating pressure of 199 Bar.

“The tool design is based on our proven 42 in. SmartPlug design,” said Larry Ryan, Director, Operations for TDW Offshore Services. “However, the exceptionally large diameter of the pipeline meant that Nord Stream required a SmartPlug tool that was 30% larger. Th[is] new tool is not only exceptionally large, but is also capable of isolation at extremely high pressures,” he added.

The SmartPlug pipeline pressure isolation method is designed to provide great value to owners and operators of pipeline systems. It makes it possible to safely isolate the area targeted for work from hydrocarbons without bleeding down the entire work zone, which is costly and time-consuming. In the case of Nord Stream, there are no mid-line valves available for use, so the entire 1220 km pipeline would have had to be depressurised, taking a significant amount of time. Given the minimal amount of gas released while isolating a work area, the new isolation tool offers more than economic benefits. It is also very effective in minimising impact on the environment.

Adapted from press release by Cecilia Rehn

Read the article online at: https://www.worldpipelines.com/business-news/27032012/nord_stream_pipeline_receives_maintenance_tool/