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sluggish at best – the pipeline ticked off two other
boxes associated with unpiggability: its circa-1970s
age and an internal design with eight acute miter
bends that made it impossible for pigs to navigate,
clean, or inspect the line.
To help overcome this genuine challenge, the
operator contracted pipeline services provider T.D.
Williamson, which provided a multistep solution
that included:
• Installing custom-designed pig
launchers and receivers at strategic
points along the line;
• Removing and replacing miter bend sections
with pipe that could accommodate
cleaning and inspection pigs;
• Performing a gauge pig run to
ensure that cleaning and inspection
tools could negotiate the pipeline;
• Using progressing cleaning
techniques to clean the line with 24
specially selected cleaning pigs;
• Inline inspection using high-
resolution tools: deformation
(DEF) technology to define any
geometric anomalies, Gas Magnetic
Flux Leakage (GMFL) technology
to locate corrosion, and the XYZ
Inertial Measurement Unit for
GPS pipeline mapping;
• Data validation and analysis.
Because the right pigs were
selected for each stage of cleaning,
the pipeline was in pristine condition
before the inspection runs occurred.
This meant that the inline inspection
tools could deliver the highest
quality data – information the
operator is using to plan repairs and
other work.
But ensuring integrity wasn’t the
only benefit the operator achieved from
the pigging program.
According to pigging solutions
expert Stephen Miska, the pipeline is now more
productive (i.e., profitable), and its operational life
span has been enhanced.
“The pigging program maximized the amount
of product that could flow through the system and
lowered associated production costs,” Miska explains.
“And as far as their life span, even for pipelines that
are 30, 40, or 50 years old, with regular cleaning,
inspection, and corrosion control, there’s no known
limit to how long they can operate.”
Like in Don Quixote, it’s futile to fight
invented enemies. But as the Polish pipeline
example suggests, picking battles wisely can create
prodigious results.
WHICH PIG TO PICK FOR THE CLEANEST PIPELINE?
I N N O V AT I O N S • V O L . V I I , N O. 4 • 2 0 1 5
7
Not only can a clean pipeline keep you in
compliance, it can also improve throughput and
corrosion control, which increases revenue and
reduces the risk of leaks or ruptures. But how do
you know which pig to select?
SPRING-MOUNTED BRUSHES
remove
hard internal deposits like scale and
corrosion.
DISCS
can push out solids, including
debris, and can run bi-directionally.
ALL-URETHANE WAX-CUTTING BLADES
can remove soft deposits such as
paraffin and sludge.
Although mainly used to seal the pig
inside the pipeline,
TIGHT-SEALING
CONICAL CUPS
also provide some
cleaning and dewatering.
CUSTOM CONFIGURATIONS
can solve
specialized cleaning issues: Pig length
can be altered, and cups and discs
can be rearranged in specific series. In
addition, certain pigs can be modified
for very heavy wall pipe or outfitted with
transmitters for tracking purposes.