Four crawling robots that can negotiate twists and turns in pipes will be working in Valdez this summer, providing the first internal peeks at 40-year-old sections of pipe branching off the trans-Alaska oil pipeline.
Alice, Dee, Fiona and Gary — as the high-tech gizmos with retractable legs are nicknamed — will scout for corrosion inside pipes at the Valdez Marine Terminal, where crude oil from the North Slope flows into giant storage tanks and oceangoing tankers.
The gadgets will use lasers and ultrasound-like technology to sniff pipe walls in a 350-foot, underground stretch of line that's part of the system delivering crude oil to some storage tanks. They're also inspecting a 48-inch conduit roughly a half-mile long that helps deliver oil to loading berths where tankers await.
In recent years, the versatile new machines have allowed the first internal inspections of other buried pipes extending off the 800-mile main pipeline that begins at Prudhoe Bay, said Katie Pesznecker, a spokesperson with Alyeska Pipeline Service Co. Some of those reviews have been conducted at pump stations that help move oil along the pipeline.
Also, the terminal and pipeline operator is currently in the middle a multiyear project at the Valdez terminal to internally examine such buried pipes, a job relying heavily on the robots.
Pipes at the terminal that have been internally investigated so far — including large stretches of piping last summer — have been found in good condition, Pesznecker said by email.
The remotely controlled inspectors are part of the RODIS family — short for Remotely Operated Diagnostic Inspection System. They were created by Diakont, a Russian-owned company with offices in the United States, to inspect pipes in the nuclear and natural gas industries.
A few years ago, Alyeska discovered it could use them to inspect oil lines that couldn't be inspected with "smart pigs." Those long "pigs" flow straight down the main line, using magnetic sensors to examine the insides.
The underground oil pipes must first be cleaned before the robots enter, flushed with hot water and detergent, or diesel fuel if needed as a solvent.
Some of those "unpiggable" secondary lines had never been internally inspected since oil first began flowing through the line in 1977. Doing so wasn't possible without a dig that exposed the pipe and increased the risk of accidents.
But the dangers of uninspected pipelines was highlighted in 2011, when a line buried underground at Pump Station 1 sprang a leak. That led to a shutdown that halted North Slope oil production, costing the state $18 million daily in lost taxes and royalty payments.
An Alyeska engineer found the Russian robots during a Google search.
The machines come with retractable appendages on track wheels, allowing them to grip internal pipe walls. They can chimney-crawl vertical sections and turn tight corners. They're tethered to operators with long cords, so they can send information digitally, providing real-time data. They look something like a no-nonsense version of the Pixar movie robot in "WALL-E."
Brian Carlson, director of pipelines services at Diakont's U.S. headquarters in San Diego, said the company has named its robots alphabetically.
The ones with female names are a bit more capable than the others, he said, because they can handle changing diameters midpipe.
Carlson said this first round of inspections in Valdez will be completed in the coming days. Later this summer, the machines and their human operators — Diakont workers — will return to the terminal for more pipe inspections.
Key to the work was the summer's first major maintenance shutdown of the trans-Alaska pipeline on Saturday, May 6. The 18-hour job allowed crews from Prudhoe Bay to Valdez to review electrical and mechanical systems at pump stations, among other tasks.
It also allowed workers in Valdez to begin preparing those underground pipes for the internal reviews.
Brooke Taylor, with Prince William Sound Regional Citizens' Advisory Council, said the federally created oversight group for the terminal and oil tankers is excited that underground portions of pipe in Valdez are getting their first-ever internal inspections.
So far, so good, she said.
"This will help us prove it's in good condition," she said of the entire pipeline system there.