ROV performs inspection in Tunisian oil field
Lundin
Petroleum, an oil company based in Tunusia, has a field of
producing wells in the southern Mediterranean.
“Periodically we need to inspect the wells and other
subsea modules”, says operations chief Nebil Tamani.
“ When there is suspected leak of hydraulic fluid, or
some other problem, we will send down an ROV to inspect the site
and make a videotape. The videos are sent to our main office for analysis and
assessment of actions to be taken.
We were renting ROVs for these inspections, but recently
we decided to purchase our own to give us more flexibility.
After examining the prices and capabilities of a number
of underwater vehicles we decided on JW Fishers SeaLion. Now, in
addition to inspecting the wells and other subsea structures, we
can also routinely inspect the hull of our FPSO (floating
production storage off-load) tanker IKDAM and it’s mooring
system.
Jack Mead, an
experienced ROV pilot employed by OceanScan UK Ltd, was recently
hired by Lundin to operate the SeaLion ROV on an inspection
project. Jack says,
“The job required the SeaLion to dive to a depth of 70 meters
(220 feet) to locate and inspect the anchor chains, pipes, and
subsea structures surrounding the IKDAM.
After connecting the system to a generator to eliminate
some problems with the ship’s power supply, I rigged up a 40
meter shot line to act as a tether management system to keep the
umbilical vertical and clear of the boat’s propellers.
The ROV was then launched from the anchor-handling
tug/supply boat. The
SeaLion’s powerful vertical thrusters allowed it to easily
descend to the required depth. There it was able to quickly
locate the chain and follow it across the bottom to the anchor.
As the SeaLion flew over the ocean floor, the tug
followed with the aid of a Fugro USBL (ultra short base line)
positioning system and an acoustic beacon attached to the ROV.
We recorded the entire inspection operation direct to DVD.”
He went on to
say, “Officials at Lundin were very pleased by how quickly and
efficiently our team was able to complete the inspection. I’ve
operated many ROVs and was very impressed with the SeaLion’s
power and maneuverability. The system performed flawlessly.”
