The lowly and usually invisible pipeline pig is not just an oilfield tool. Any industry that uses a pipeline to transfer liquid from place to place uses pigs to clean the insides and to check structural integrity. Food, industrial chemicals, water, and other fluids can flow a few feet across a plant or thousands of miles cross-country. Wherever pipelines are, pigs are inside.
They’re also used as sort of room divider in batching systems. A single pipeline can be used to transfer a variety of liquids, with pigs in between. Oil midstream companies can alternate refined products such as gasoline, jet fuel, and others between batches. Pigs also make bidirectional systems possible.
Girard Industries in Houston has been making pigs since 1958. The company’s general manager, Michael Henry, said the pandemic shutdown put some of their clients into almost a panic about whether Girard was still open.
“We were getting—no exaggeration—weekly phone calls from representatives of big and small oil companies who were checking in to say, ‘Hey, are you still out there and open for business?’”
Though calls were mainly from oil and gas companies, they also came from Girard’s clients in many of the other industries listed above.
As vital as those clients consider Girard, not all of them stayed on their pigging schedules during the downturn, Henry noted. In addition to cleaning pipelines, Girard makes pigs whose function is to check the integrity and efficiency of lines—and here’s where some clients felt the need to cut back due to sales slowdowns and revenue losses during the pandemic’s tightest shutdowns.
“For some, maintenance was the first thing they cut from their budgets,” reducing the frequency of pig trips by about half in many cases.
While there was less product moving through those lines, Henry pointed out that there is no less need to check integrity, because corrosion is not solely a result of product passing through. He feels that those companies could put themselves at risk of having to spend more when a problem is found because it will have gotten bigger during the wider intervals between maintenance checks.
By identifying corrosion and other potential issues, regular pigging can prevent or detect breakage, spillage, and other issues as part of the operators’ due diligence. In normal times, most midstream companies are strongly focused on following safety protocols and reporting, Henry said.
For several years during the booms of 2010-14 and again in 2018-9, most Permian pipelines were at capacity, making pigging of all sorts—cleaning and inspecting—a top priority. The cleaning process involves a pig designed to scrape the sides of the pipeline, like a squeegee on glass, Henry said. In oil lines it scrapes out paraffins and other impurities, while in gas lines its primary job is to collect condensed NGLs.
These collected impurities are deposited at the pig’s receiving station at the end of its run. In the case of NGLs in a gas pipeline, these are usually recovered and sent into the appropriate sales line.
The Uncertainties of 2020
COVD-19 was one damper on the pig business, but 2020’s other major shift, toward renewable energy, put the clamps on several major pipeline projects—shutdowns that affect future business for pigs. Henry noted that both events have put many of their clients on hold. Those clients are waiting to see if oil prices stay up and if regulatory burdens stay down before pursuing new projects.
Cancellations and delays of pipelines such as Keystone XL, Line 2, and others have played havoc with investment plans for several Girard clients. Some have become so frustrated with the start-stop waffling as administrations change, that they’ve abandoned certain projects altogether—pipelines that would have required large pigging operations.
Pigs Learn AI
It might seem incongruous to discuss a connection between pigs and software or anything more complicated than where to exit the pipeline. But Houston-based WeldFit offers technology aimed at pig improvements that would make pipelines safer and more efficient. Company VP Adam Murray explained how that works.
As midstream companies increase monitoring efforts by installing sensors to measure pump activity, pipeline pressures, and flow rates, he says it was only natural that pigging should become part of that process.
“Automation’s out there—the technology exists,” Murray said. So it seemed to time for a company like WeldFit to connect “pig monitoring services together with automated pipeline pigging. Combining that with multiple pig launchers [which his company offers], that data can capture pretty much everything you need.
“That is what’s really changing the pipeline—24/7 data collection provides real-time analysis.” Technicians no longer need to physically inspect any location unless there is a known issue.
He said that the February deep freeze in Texas saw several WeldFit customers keeping a close eye on pig launches, pipeline pressures, and other data from a safe and relatively warm living room. “Even if they didn’t have power, they were able to be on their cell signal and on an app and have complete control of their system.”
In all situations, tracking pressures and flow rates helps with resource optimization, said Murray. Simply reducing site visits, many of which require an hour or more of windshield time each way, is a huge cost saving.
As with most automation systems, this reduction in site trips is also a safety gain. The fewer people there are on the road, the safer things are for everyone.
Specifically, “If you have an automated launcher with seven pigs and you’re launching once a day, that’s a seven-x improvement on road time; that’s a seven-x improvement on safety on the road; that’s a seven-x improvement on pipeline safety because you’re only interacting with it once a week instead of once a day [to collect the pigs downstream and return them to the launch point].”
He noted that every time a pig is loaded there’s an entry point that can create an emission or a leak or other safety or environmental issue.
The extensive data collection associated with so many sensors yields economic benefits as well. “Any sort of data collection you’re doing always leads to analytics, which always leads to visibility, which always leads to easier reporting.”
Real-time pressure monitoring allows paraffin-cleaning pigs to be launched when and where a buildup is detected. “In the tracking we do and in the sensors in our launchers and receivers, and others, you can see real-time pressure differentials. So if liquids start building up in a low spot in a pipeline—from paraffin or something else, you can start to see the pressure change.
“When it changes more than your set parameters, you can tell it to automatically fire a pig” to clean out any collected substances.
He continued, “It’s a powerful tool. Pipeline 2.0 is real.”
2020 Vision
For all its challenges, the year 2020 did force companies to ferret out efficiencies in order to stay alive. Across the board this thinking helped tech companies like WeldFit to show what they could do.
“I feel like in our industry we’re able to react appropriately,” Murray said. “A function of downturns and this pandemic, in oil and gas, is that that’s when innovation happens. We had a downturn in ’07-’08 and that opened the frac’ing/horizontal drilling revolution. So I’m excited to see what other technologies and what other advancements come about as we start to get back above $60 oil.”
The year 2020 was also when ESG became a leading factor in equity decisions—and Murray is convinced that automating pig launching contributes to that. Making that data visible to investors is part of the data gathering process.
“It’s our job as manufacturers and as industry to provide an offering in which we can show up to an 85 percent reduction in emissions by using one of our launchers versus the traditional launcher.”
Using data to right-size pigs is another way in which automation and data collection can boost efficiency.
It is true that pigs have been in the “out of sight, out of mind” category, but Girard’s Michael Henry has noticed a greater interest in these small items in recent years. Some of that he attributes to the Great Crew Change, where younger people in the industry readily use smart devices for research, including the care and feeding of pipeline pigs. Greater pig education is leading to more understanding of their basic uses for cleaning and maintenance. But it’s also creating interest in uses for batching systems.
And with technology such as that from WeldFit, pigging may now be getting the respect it deserves.
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Paul Wiseman is an oil and gas freelance writer. His email address is fittoprint414@gmail.com