Underground Construction - May 2021 - 25

Warrior's New Tool Sets
Pipe Extraction Record
For some time, pipe or pipeline removal and extraction has
become a common occurrence. Either because of pipe failure or
environmental changes, pipe extraction is more prevalent today.
Extraction or removal is expensive, and the possibility of incomplete removal is always present. Paying attention to this problem,
Warrior Field Services (WFS), Lufkin, Texas, set out to improve the
pipe extraction process.
WFS has developed a pipe extraction tool that can safely remove
pipe sections installed traditionally or using horizontal directional
drill (HDD). This patent-pending process is non-destructive, does
not require excavation or dredging, and requires no divers or barge
work in maritime conditions. That means it's safer for workers, and
protects the environment and surrounding infrastructure, as well.

Extraction process

On Oct. 5, 2020, a contractor for a major pipeline company drilled
3,300 feet of 12-inch, 0.375 wall pipe under a residential area at
a depth of almost 200 feet. This drill was part of a multi-mile new
pipeline project to transfer ethane.
Upon completion in late January, the entire system was
pressured up for a final hydrotest. During this test, the pressure
inexplicitly dropped. After looking for leaks, the test was restarted
and failed again. Soon it was determined that a leak was present
somewhere in the 3,300-foot HDD section.
The original installer of the HDD section was remobilized to
extract the pipe, but the effort failed. The pipeline company's
engineering team determined that only 500,000 pounds of force
could be generated during the extraction, which clearly wasn't
enough. With the cause of the leak undetermined, the idea of
using a pneumatic hammer to assist in the extraction was rejected.
Engineering did not want to take a chance of damaging the pipe in
the extraction efforts, since they were not able to determine the
exact cause of failure.
In early February 2021, the owner inquired about WFS' process
of non-destructive pipe extraction and gave the Luftkin company
the opportunity to apply it to the HDD section. As soon as WFS
mobilized, it advanced the extraction tool downhole 900 feet on
the east side of the HDD drill, and then removed the tool to clean
the hole of cuttings.
During this time, the massive winter storm hit Texas, causing
widespread power and water outages. Because of this unprecedented weather, all parties involved determined the working conditions
were unsafe and, therefore, suspended the project for three days.

Curveball

After resuming work, WFS began resending the extraction tool
downhole. After only 500 feet, the tool encountered resistance and
forward progress halted. While trying to determine why the advance
was stopped short of the 900 feet that had been obtained only a few
days earlier, WFS discovered a major problem had since occurred.
When the work was paused, the pipeline contractor installed
a pull-head on the HDD pipe for WFS's extraction efforts.

Unfortunately, a set of line-up clamps were inadvertently left
on the pipe. During the winter storm, the bell hole at the east
side had filled with melted snow and rain, which hid the line-up
clamps from view.
In turn, when WFS began the readvancement downhole, the
line-up clamps were carried 500-feet downhole until they lodged
in the formation. This obviously halted all extraction efforts from
the east side. With this downhole obstruction, WFS was unsure
about the ability to proceed.

Plan B
The line-up clamps had to be removed from the hole. Drilling a new
hole and abandoning the current path and pipe was impossible
due to ROW constraints. After some discussions, WFS removed its
extraction tool from the east side and installed it on the west side.
As it began advancing the tool, WFS stopped at various times
to bottom up the hole and clean the cuttings out. At 2,800-feet
downhole from the west, the driller reported that he had hit the
line-up clamps. WFS then slowly advanced its tool toward the east,
and pushed the clamps back and off the pipe, saving the hole.
After the extraction tool was advanced the entire 3,300-foot
length of the HDD bore, WFS connected the pipe to the drilling
rig on the west side. According to the original driller's log, the
HDD was installed at a maximum pullback of 140,000 pounds five
months earlier. Since pipe had been in the ground for so long, it
was uncertain what force would be required to move this section.
To everyone's surprise, at only 75,000 pounds of force, the pipe
started to move. At this point, WFS moved the HDD rig out of
the way, and turned the pipe over to the pipeline contractor. The
contractor hooked a dozer to the pipe, and 10 minutes later, the
entire HDD pipe section was once again above ground.
CCI Inspection was hired to oversee the HDD inspection on this
project. After the pipe was removed, CCI informed WFS that its
efforts had resulted in setting a world record for pipe extraction.
No other pipe or HDD section of this length or depth has ever
been removed without the use of excavation, destructive methods
or a pneumatic hammer. WFS removed the section without these -
and entirely intact. *
FOR MORE INFORMATION:
Warrior Field Services, (936) 632-5552, warriorfsllc.com
UCONonline.com | MAY 2020

http://www.warriorfsllc.com http://www.UCONonline.com

Underground Construction - May 2021

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