Pumps provide longevity and reliability to torque-and-test units for Texas-based contractor running high-pressure water tests.
Checking blowout preventers for leaks is a critical step before oil companies begin drilling operations. As such, the last thing contractors such as Frontier Services need is testing equipment that’s prone to breakdowns — which is why the company relies on pumps made by Reliable Pumps Consultants to build its own torque-and-test units.
“We own about 30 torque-and-test units, and they all use pumps made by Reliable,” says Justin McGehee, a co-owner and operations manager of Frontier, headquartered in San Antonio, Texas. He and his partners bought the company in 1995; it provides wellhead services throughout Texas and parts of Colorado. “When we buy pumps, we’re looking for longevity and reliability. Some of our pumps were purchased back in the 1980s and are still going strong.
“They’re extremely reliable,” he adds. “I guess that’s why they’re named Reliable Pumps.”
The pumps generate maximum pressure of 20,000 psi and can pump up to 13 gpm. Transported on flatbed trailers made by PJ Trailers and pulled by Dodge and Ford four-wheel-drive pickup trucks, the testing units include two 300-gallon water tanks and a 110 hp diesel engine made by either Deere & Co. or Perkins Engines.
To test blowout preventers, Frontier crews also rely on torque wrenches made by Torq/Lite and Barton chart recorders made by Recorders Charts & Pens. The chart recorders are used to formally document the pressure at which each section of the preventer was tested and how long the pressure was held; that information is provided to customers and regulatory agencies, McGehee says. “The drilling companies want to know that everything held before they start going down 20,000 feet to drill for oil,” McGehee says.
Located right below a drilling rig, a blowout preventer seals a well shut if drillers unexpectedly hit a high-pressure zone deep underground, which would send dangerously large volumes of oil rushing to the surface. As such, the blowout preventers are essential to safe drilling operations. The most famous blowout-preventer failure occurred on the Deepwater Horizon drilling rig in the Gulf of Mexico in April 2010; the accident killed 11 employees and released roughly 5 million gallons of crude oil into the Gulf.
To ensure blowout preventers are working properly, Frontier crews “torque up” the large assembly of valves by tightening all bolts with high-torque wrenches that apply pressure of up to 10,000 psi. Then they set a large iron test plug in the bottom of the wellhead and pump water into the well and the body of the preventer under high pressure — anywhere from 3,000 to 8,000 psi. Rams at the top of the wellhead are closed to seal off the top of the well, creating a contained, pressurized area, McGehee says.
“We hold the pressure for five or 10 minutes, depending on what the customer wants,” McGehee explains. “We check all the valves in stages, making sure that nothing leaks. We record our (pressure) ratings on a chart recorder whenever we pressure up.
“The testing is extremely critical,” he adds. “You never want a blowout on location. Just look at the BP (British Petroleum) blowout (in the Gulf of Mexico) and all the money that cost the company. Not only that, people can get seriously hurt or even killed.”
Because the pressure testing is so important to drilling safety, this is one oilfield operation that’s not a race against the clock. “Speed is not important,” McGehee says. “It’s definitely not a race. You definitely want to find every leak.”
A typical pressure test can take anywhere from six to 16 hours; McGehee recalls one that lasted three days because crews kept finding leaks.
The unit’s two water tanks generally don’t need to be refilled during most jobs because each test uses only 15 or 20 gallons of water. “We’re not pumping a whole lot of volume,” he notes. “The orifice in the blowout preventer is very small.”
One factor that contributes to the pumps’ longevity: They operate only in short bursts, usually about 10 minutes at a time. McGehee estimates that if a test takes 24 hours, the pump might run for a total of about two hours.
“We test frac stacks, too, which are an assembly of valves used to cap off a well after a drilling rig is moved off,” McGehee explains. “It’s just like doing a static-pressure test on a new house to make sure none of the plumbing is leaking. On some frac stacks, we might put 10,000 to 12,000 psi of pressure on them to test them.”
The pumps last a long time because there aren’t many moving parts. In fact, the engine that drives each pump is the one component most prone to failure, McGehee says.
“Or the Teflon packing in the pumps sometimes fails,” he says. Either way, he says the Reliable pumps are easy to repair. “We can tear them down and rebuild them in no time,” he says. “That’s important because if something happens on location, we want to minimize downtime.”
With a price tag of about $100,000, which includes a full complement of tools and accessories such as test plugs and torque wrenches, the pumps don’t come cheap. But are they a good investment? “Heck, yeah,” McGehee says. “There’s no reason in the world it can’t pay for itself within six months, depending on how busy you are.”
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