New technology focus article, Locked In: Offshore Isolations.

1. T E C H N O L O G Y F O C U S
Locked In:
Offshore Isolations
Companies that create technology are always working on
the next big idea.
Often, innovation originates from breakthrough, whiz-bang,
lightning-strikes thinking.
But sometimes, instead of a revolution, an evolution will do just fine.
And sometimes, that evolution begins with a little prompting from
the marketplace.
Such is the case with the hydraulic locking capabilities of the
tetherless, remote-controlled SmartPlug® isolation system. Evolving
versions of this non-invasive plugging technology have been isolating
offshore pipelines for more than 20 years. SmartPlug tools, designed
by pipeline service provider T.D. Williamson (TDW), remotely
isolate and stop product flow to a designated area of the pipeline
so that maintenance, repair or tie-ins can be performed in a safe,
inert environment.
A key component of the system is its ability to hydraulically lock into
place during isolation in a lower pressure line. This locking mechanism
supplements, or can even replace, pipeline pressure differential to more
securely hold the isolation tool in place.
Without hydraulic lock capabilities, and in the case of a substantial
drop in pipeline pressure, the differential pressure across the plug could
diminish to a point that the tool could naturally begin unsetting. This
would cause both the pipeline operator and service provider to take
immediate corrective action, resulting in delays and wasted time and
money, potentially jeopardizing the whole operation. But hydraulic
locking capabilities provide an additional level of safety and security,
allowing the tool to maintain the isolation regardless of pressure changes
within the pipeline.
“Hydraulic lock capability greatly increases safety during pipeline
isolation,” Gary Anderson, Director of SmartPlug Technology, explains.
“By continuing to expand the locking function across all sizes of the
tool, operators will ultimately benefit from the same safeguards and risk
mitigation, regardless of the diameter of their line.”
Hydraulic Locking a Necessity
SmartPlug tools come in a variety of sizes – for every pipeline diameter
from 8 inches to 48 inches, there’s a unique, specific isolation tool with a
proprietary intelligent control system to match. Offshore operators who
had experience using the SmartPlug tool in larger diameter pipelines

2. asked TDW to add hydraulics to the control system
for use in their smaller diameter lines. According to
Anderson, not only do operators see the technology
as desirable, some believe it’s a necessity.
Anderson cites an example of an operator
working in the Gulf of Mexico who sees hydraulic
locking capabilities as a requisite part of its
plugging operation.
“For this operator, the hydraulic locking
capability is a ‘must-have’ safety feature,”
Anderson says. “The client needs to isolate a
smaller diameter pipeline, but the previous
control system for this particular size of
SmartPlug tool didn’t yet have the ability to
hydraulically lock the tool in place.”
This need expedited the introduction of the
next generation of control module that will bring
the tool within the client’s operating guidelines and
provide the requisite level of safety and redundancy.
All SmartPlug control systems are operated
topside by laptop computer. The system uses
extremely low frequency technology to enable
communication so the operator can send commands
and receive real-time, two-way, through-wall data
about plug, pipeline and other key conditions.
The newest control module continues to expand
the locking options for operators of smaller diameter
lines. But, regardless of diameter, operators continue
to rely on the DNV-certified, double block safety of
the SmartPlug® isolation system.
Risk is defined by Det Norske Veritas (DNV) as, “the
qualitative or quantitative likelihood of an accidental or
unplanned event occurring, considered in conjunction with
the potential consequences of such a failure. In quantitative
terms, risk is the quantified probability of a defined failure
mode times its quantified consequence.”
The SmartPlug isolation system provides operators with
options for self-locking technology in high pressure lines
and hydraulic locking for use in low pressure. Both choices
provide a double-block method to greatly reduce risk, as
every SmartPlug tool receives a Type Approval Certificate from
DNV, confirming compliance with DNV-OS-F101 standards.
Certification includes a detailed Failure Mode, Effects, and
Criticality Analysis study based on a Fault Tree Analysis.
Doubling Risk Reduction
SmartPlug® isolation technology featuring
hydraulic locking in low pressure lines