Boring - Trenchless International

Pipe cleaning
April 2010 - Trenchless International
The 150 mm diameter pipeline is ten
kilometres in length, pumping raw water
from the Dawson River to the treatment
plant to service parts the Duaringa Shire,
Queensland, Australia.
Mission:
To remove the internal debris and
weed growth built up in the pipeline over
a period of ten years.
Due to the location of the site and
the urgency of the program, Clearflow
Australia worked purely on telephone
communication and faxed documents
in order to fabricate a pig launcher to
suit the conditions onsite. After some
difficulties it was made to fit and is now
a permanent fixture of the pipe at the
river end.
Managing Director David Elderfield
said “On inspection of the pipeline at the
river and pumping end we adapted the
existing fittings, removed a flanged section
of the existing pipe and made our
pig launcher fit.
“The best location for the discharge
was at the water plant. A section of pipe
was exposed and removed with the
excavation of pit leaving the open end of
the pipe discharging into the settling pit.”
There was no confident local knowledge
of the pipeline and the only map
available was a longitudinal section map,
said Mr Elderfield. “It is difficult to know
what to expect when launching a pig that
A brush pig uses both metallic and
non-metallic brushes. Generally, brushes
are used when more aggressive cleaning
is required to remove tough debris.
Liquids pipelines are best cleaned with
a pig equipped with cleaning devices
attached, such as brushes, which can
remove fine solids that may have settled
in the pipeline.
Pigs for different pipes
Different pigs are recommended for
water, natural gas, oil and liquids pipelines.
The type of cleaning pig used on a
natural gas pipeline is often determined
by the internal coating of the pipe. If the
pipeline is internally coated, the cleaning
pig to be used won’t be equipped with
cleaning devices that could damage or
remove the coating. For example, a polyurethane
pig won’t damage the coating. If
Dawson River case study – pigging raw water line
is required to travel ten kilometres and
at the same time achieve the desired
results.”
Most of the pipeline is located in
bush terrain with difficult access, with a
number breaks in certain sections and
unknown debris in the pipe.
As the pipeline had no offshoot
sections or designed breaks it was necessary
for the pig to travel the entire
ten kilometres and achieve the desired
result. If the wrong type of pig is used
and too much debris is dislodged too
early the pig could jam up in the pipe.
On the other hand, if the pig is too soft
it may break up during the run. Or if the
pig travels too quickly we may not get a
true idea on the condition of the pipe or
the type and amount of debris that is in
the pipe to be removed.
At the time of fitting the launcher the
pipeline showed signs of encrustation
with a large amount of weed slime and
sludge – the aftermath of pumping raw
water.
Clearflow’s normal procedure on the
first run is to try and determine the
condition of the pipe. The first run took
approximately four hours to travel the
pipe, removing large amounts of sludge
and slime.
This initial run was not without complications.
The pig did jam up with the
amount of debris in the pipe and it was
decided to release the pressure in the
the natural gas pipeline is free of internal
coating, a cleaning pig with brushes can
be used.
Plastic-bristle foam pigs can also be
used with internally coated pipelines or
plastic lines such as PVC, fibreglass and
high-density polyethylene. The bristles are
forceful enough to remove most build-up
but not harmful to the coatings.
Oil pipelines may need pigging to
remove wax accumulations on the
inside of the pipe wall or an accumulation
of water in the pipe. A polyurethane
pig is suitable for removing wax from an
oil pipeline.
It is important that the right cleaning
pig is chosen for an operator’s pigging
needs. There are a number of suppliers
in Australia providing different pigging
products, all willing to help with the right
pigging solution.
pipe. In doing so, Clearflow drained
some of the pipe to get another run
with the pig and to try and dislodge the
debris.
Under normal conditions the first-run
pigs or proving pigs will float, however,
in this case, when they were finally discharged
from the pipe they were so full
of sludge and slime that they just settled
on the bottom of the discharge pond.
They were stuck in the sludge and at the
bottom of the pit.
It is necessary when refurbishing pipelines
to try and control the speed of the
pigs through the pipeline. After two proving
runs, the company was confident
the pipeline was reasonably true and
launched the working pig; a harder compound,
poly-foam pig.
The purpose of running this pig was to
remove all of the debris of weed sludge
and slime as well as any harder encrustation.
The results achieved were very
good. Clearflow not only removed large
amounts of raw water slime sludge and
weed growth, but also the heavy scale
evident in the bottom of the discharge
pit. There were also signs of manganese
mixed up with the weed growth.
The final analysis
Improved water quality delivery with
increased flow rate to the dam of 60 per
cent. This alone decreased the operating
costs of pumping water.
Bigger than Texas:
PPIM puts pigs on show
A dynamic forum discussing key trends, products and services in the pipeline inspection sector – the 22nd
Pipeline Pigging and Integrity Maintenance Conference and Exhibition was held in Houston, Texas, from 15–18
February 2010.
The Pipeline Pigging and Integrity
Maintenance (PPIM) Conference and
Exhibition, organised by Tiratsoo
Technical, a division of Great Southern
Press, and Clarion, drew engineering
management and field operating personnel
from both transmission and distribution
companies concerned with improved
operations and integrity management.
Reporter Lyndsie Mewett was in attendance
and here delivers a wrap of the pigs,
people and program at PPIM.
The event encompassed training
courses, a varied Conference program
and an Exhibition including 74 companies.
Approximately 1,500 people
attended, with 400 delegates representing
22 countries enrolled in the Conference
and training courses.
A captivating Conference
Tiratsoo Technical Principal John
Tiratsoo chaired the Conference sessions,
which included topics such as the importance
of pig trap assessment, integrity
management plans, multi-diameter bidirectional
pigging, magnetic flux leakage
(MFL) inspection capabilities, pipeline
regulatory updates, performance management
assessments and remediation,
and unpiggable pipelines.
The Conference program also included
a panel discussion on the cleanliness of
pipelines from an owner/operator perspective.
Six panellists from different parts
of the pipeline industry outlined what
‘clean’ means to them, which proved a
useful insight for contractors to assess
what products would best suit proponents’
needs.
Pigs on show
In conjunction to the Conference, the
well-attended Exhibition highlighted the
latest products and services available
to the pipeline pigging and inspection
industry.
Companies displaying products
included A.Hak Industrial Services, Apache
The Conference Panel Session in full swing.
Pipeline Products, Baker Hughes Pipeline
Management Group, BJ Pipeline Services,
DNV, Dresser, Girard Industries, Hebna
Corporation, Knapp Poly Pig, Rosen and
T.D. Williamson, plus many more.
Event gold sponsors BJ Pipeline
Services and Rosen provided evening
drinks and nibbles in the Exhibition area
during the event. This gave Conference
delegates and exhibitors alike a chance
to talk shop in a relaxed environment or
simply unwind with new and old friends.
A bright future for PPIM
The importance of the pipeline inspection
industry continues to grow. As
60 per cent of the world’s major oil and
gas transmission pipelines are now more
than 50 years old, keeping up with the
latest inspection and rehabilitation technology
is vital.
The success of the 22nd PPIM
Conference and Exhibition echoed this
sentiment, with many Exhibitors already
signing on for Houston’s 2011 PPIM event.
Tiratsoo Technical's John Tiratsoo chairs the
Conference sessions.
PPIM training courses
Seven streams of training
courses were ran on the 15 and
16 February, encompassing
topics such as defect
management, pigging and inline
inspection, pipeline repair
methods, performing pipeline
rehabilitation and pipeline risk
management.
For information about future
courses, visit Clarion’s website
www.clarion.org
In addition to the Houston PPIM
Conference and Exhibition, PPIM Asia
Pacific will be held later this year in
November. Training courses will be
held 8–9 November with the Conference
beginning on Wednesday 10. Why not
drop by following Singapore International
No-Dig?
Make sure you keep an eye out for more details on PPIM Asia Pacific – visit www.clarion.org
Pipe cleaning
April 2010 - Trenchless International
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