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I N N O V AT I O N S • A P R I L - J U N E 2 0 1 4
would cause the loss of a significant amount of
product, massive gas flares, and lengthy shutdown of
the gas supply from the line to the island.
Since that option was clearly unattractive, SPEX
chose to explore isolation. During an isolation
exercise, a short portion of the pipeline housing the
valves is shut off from the rest of the pipeline and
depressurized. Once the isolation is secured, the
valves can be replaced.
A proven method of isolation involves the
SmartPlug® tool. SmartPlug technology has been
used for more than 20 years to isolate portions of
pipelines, while withstanding maximum allowable
operating pressure. The process involves pigging the
SmartPlug tool to the isolation point and setting the
plug. While the plug is navigating the line, a wireless
communication system – called the SmartTrack™
System – allows engineers to track its movement.
Once the plug is in the proper location, the engineers
use SmartTrack technology to remotely set the plug.
As it was critical that the shutdown time be kept
to a minimum, SPEX opted to use the SmartPlug
tool to isolate their line.
“SPEX appreciates that bleeding down an entire
gas export pipeline is time-consuming and costly,
so we chose instead to deploy pressure isolation
of the line downstream,” said Sarawak Shell Sdn
Berhad/Sabah Shell Petroleum Project Manager
Nathan Stephenson.
SPEX’s decision to use SmartPlug technology was
a resounding success. The operation was completed
without incident, and the island’s energy supply
remained intact.
Beyond Maintenance: What Operators
Don’t Know About Isolations
Valve maintenance – maintenance similar to that
undertaken by the operator for the aforementioned
Philippines project – is the most common SmartPlug
operation. However, according to Rolf Gunnar Lie,
TDW Regional Manager of Business Development
in the Far East Asia Pacific, SmartPlug technology
can be used for much more.
One growing SmartPlug application is the
isolation of subsea pipelines during massive
construction projects. During construction, heavy
equipment is lifted and carried over the underwater
pipes. It goes without saying that dropping a multi-
ton object on a pipe could result in a catastrophic
spill. By isolating a short portion of the pipe,
construction work can continue with significantly
reduced risk and the contents of the rest of the
pipeline can remain in place.
Other perhaps lesser known SmartPlug
applications in use today are isolations for
hydrotesting, midline repair and tie-ins.
Gary Anderson, Director of SmartPlug
Technology, cites the ability to extend the life of
subsea reservoirs as a cutting-edge SmartPlug tool use.
“We want to extend the life of subsea reservoirs by
planning a bypass location and booster station during
pipe lay. The booster station would lie dormant until
the pressure from the reservoir no longer produced a
strong flow of product. At that point, we would pig
down the SmartPlug tool, isolate the pipeline, and
reroute the flow through the bypass and booster.”
TDW has already achieved a record 299 day
isolation, but these reservoir-extending isolations
would be in place much longer, perhaps three to five
years. Anderson projects it will be available soon.
Until then, operators will likely continue to
use SmartPlug isolations in their most well-known
capacity: as a low-risk, cost-saving alternative to
blowing down lines for planned maintenance.
SmartPlug technology uses two independent
plug modules – each of which is capable
of isolating the full pipeline pressure. This
independence provides a true double-barrier in
the unlikely event that one of the systems fails.
It’s because of this redundancy that
SmartPlug technology meets the Norwegian
Det Norske Veritas (DNV OS – F101) and other
stringent standards & requirements for pipeline
pressure isolation.
A Positive Redundancy
