Thanks to innovative isolation technology, the expense incurred by bleeding down the entire pipeline to prepare for these tasks is a thing of the past.
The name of this technology is the SmartPlug® pressure isolation system, which has proven to be a reliable, cost-effective method of isolating pipeline pressure.
Double-barrier isolation technology
During design, it was critical that the isolation tool meet the requirements for double barrier, in keeping with offshore standards and recommended practices, namely DNV-OS-F101 and DNV-RP-F113.
Working in close cooperation with DNV GL to make certain the tool would meet with these standards and function with isolation plugs that form a double or single pressure barrier in the pipeline, the collaboration resulted in the remote-controlled SmartPlug pressure isolation tool, introducing the double block and monitor method of pipeline pressure isolation.
Approved by DNV GL: the double block and monitor method
“The SmartPlug system is fully certified by DNV GL, and is a pipeline pressure isolation system equipped with two completely independent barriers and sealing systems,” said DNV GL Oil and Gas Principal Engineer – Pipelines and Materials Dag Øyvind Askheim.
“It satisfies the standard for what DNV GL deems to be double block and monitor isolation.
“The development of the SmartPlug tool illustrates how DNV GL works with the oil and gas industry to help it work smarter, safer and greener; in this case, to facilitate effective pressure isolations, with a view to reducing cost and speeding pipeline repairs.”
The SmartPlug system is comprised of two independent plug modules, and, if required by the operator, a third module for hydrotesting.
Each of the two independent plug modules can act as a barrier against full pressure on its own, successfully isolating pressure by completely sealing the pipeline.
The presence of the second plug module further increases safety.
The combined effect of activating the second plug module and reducing pressure across the modules, spreads the pipeline stress across the two modules.
As a result, stress on the line is further reduced during the isolation.
Independent gripping systems
The two plug modules have their own individual gripping system, also known as slips, which operate as separate systems, completely independent from one another.
The plug module is held firmly in place by the locking system, preventing it from shifting within the line.
Coupled with the independent sealing element, or packer, it uses the energy produced by the pressure in the pipeline to create a failsafe isolation.
Each plug module is independently tested in a test pipe to 1.43 times the operational pipeline pressure as part of the Factory Acceptance Test (FAT).
A safe measure
Reducing risk and increasing uptime during pipeline interventions is extremely important.
The SmartPlug tool’s ability to not only form a double pressure barrier, but to monitor pipeline integrity throughout the intervention provides operators with peace of mind, secure in the knowledge that works are being carried out safely, with minimal disruption and loss of production.
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