Overcoming the challenges of subsea drilling.
October 10, 2012
by Nordahl Flakstad
It sounds unfathomable. Located in Edmonton, more than 1,000 kilometres from tidewater, MARL Technologies Inc. has built a sophisticated, remote-controlled device that’s been boring into the seabed three kilometres below the surface of the Pacific Ocean off Australia. Unlikely as this scenario seems, it’s true.
Discovering how the Edmonton-built underwater device finds itself at such depths requires drilling into some corporate history. Best placed to tell the story is MARL founder and still-active manager Ron Innes. In the late 1950s, he provided drilling services to engineering and construction companies doing soil testing. But he found it hard to acquire suitable equipment – especially drilling units that were compact and light enough for transport to remote locations aboard Lockheed Electra and Twin Otter fixed-wing aircraft, or even Bell helicopters. Necessity spurred invention and his company, Mobile Augers and Research Ltd., which pioneered the use of continuous dry auger drills in Western Canada, started developing and building drilling units for its own use.
By 1977, Innes had established MARL as a sister firm to custom-manufacture drills for Mobile Augers. Soon it was taking orders for drills mounted on trucks and tracked vehicles from other firms serving the geotechnical industry. MARL’s reputation for producing innovative and technically superior – though Innes stresses, by no means, less-expensive – drills spread far beyond Alberta. A particularly fortuitous linkage occurred in 1992 when a Vancouver business contact at ConeTec connected Innes with John Gregg, president of Gregg Drilling & Testing Inc., a prominent subsurface sampling and investigation firm headquartered in Signal Hill, near Long Beach, Calif.
At the time, a so-called cone penetration test (CPT) used to determine geotechnical properties of soil, was popular in Europe but just coming into its own in North America. Gregg Drilling wanted a truck-mounted unit to house CPT testing equipment. (From the outside, trucks employed in soil and environmental testing look much like the seismic and other equipment-laden trucks common in the oil patch). MARL proved up to the task. It designed and built hydraulic presses capable of applying the 30 tonnes of pressure needed to push the sampling cone into the ground and exert 70 tonnes to extract it.
MARL took the initiative and manufactured a truck that exceeded Gregg’s expectations by including add-on features such as an onboard toilet. The overall high technical quality of the product generated additional orders from Gregg Drilling, and cemented a business relationship that has lasted to this day.
As a result, Innes wasn’t all that surprised four years ago to receive a phone call from Gregg. However, he was a bit more bemused when Gregg told him he was looking for someone to help manufacture a drill able to operate remotely 3,000 metres below the ocean surface and drill 150 metres into the seabed to obtain core samples. This, while being controlled by an operator aboard a support ship located up to five kilometres from the borehole.
A skeptical initial response was: “John, do you know how much salt water we have in Edmonton?” Gregg retorted: “I know people who know about salt water. I need people who know about drills and how to build them.”
So the landlocked Edmonton firm was launched on an improbable subsea adventure. Three years later MARL would see its handiwork plummet to the very depths of Davy Jones’s Locker.
Major technical advances have been made in the development of motion-compensating ships where drillstrings are lowered and powered from a vessel on the surface to penetrate the seafloor in search of oil or gas, or to explore the earth’s mantle. However, as they delved into the design process, members of the MARL engineering team soon discovered they were developing a very different denizen of the deep. MARL was challenged to reach new innovative heights – or more accurately, new depths.
“It was a challenging project and you do wonder just how we got the contract given where we’re located, but it was a very rewarding,” says D.J. Elford, a mechanical engineer and seven-year MARL staffer who was part of the engineering team that worked on the design of the underwater drilling platform for about two years.
It was, Elford stresses, very much a collaborative effort inside and outside MARL. In addition to working with Gregg Drilling’s marine subsidiary, MARL collaborated closely with Schilling Robotics LLC, another California company tasked with engineering the telemetry controls and power systems.
Diving is all about the right balance between daring and deliberation. Certainly MARL had to strike the right balance. The challenge lay in designing something not so heavy that it would snap the cable used to lower and raise the drilling structure with a ship-based launch and recovery system (LARS). This same cable served as the umbilical cord delivering power to drive a 150 hp electric motor and providing a communication link between the remote-control drill below and the mother ship above. The 10-tonne (in air) drilling structure is 3.8 metres wide, 5.4 metres long and 6.6 metres high.
The structure had to be tough enough to endure the saline marine environment as well as withstand
underwater pressures of 5,000 psi.
“Every hydraulic and moving item had to be compensated to accommodate the pressure,” Innes notes.
MARL was accustomed to fashioning landlubber versions of its drills almost exclusively from steel. In contrast, the SubSea Drill components are about 85% aluminium. Alignment of all working parts was critical – and where possible – systems were simplified to ensure everything lined up properly. As Daniel Teeuwsen, an 11-year MARL veteran and leader of the SubSea Drill design team explains: “When the drill is 3,000 metres below the surface, the operator can’t just jump down and kick things to line them up.”
MARL took approximately a year to actually build the SubSea Drill. Innes is proud of the staff’s efforts on the project, one that “was more taxing that anything else that we’ve taken on.” Besides the fulfilment of seeing a functioning product, MARL recently had the satisfaction of receiving a Project Achievement Award from the Association of Professional Engineers and Geoscientists of Alberta.
Somewhat akin to how the space program pushed the technical boundaries and led to benefits applicable in other fields, the SubSea Drill initiative is likely to produce similar dividends. For instance, at MARL’s 18,000-square-foot manufacturing and machine shop in southeast Edmonton, its 25-member production team has become much more adept and familiar with aluminium welding. More aluminium components are being integrated into products geared toward terrestrial use. Also the more-corrosion-resistant and lighter aluminium products could prove particularly beneficial for geotechnical firms working in harsh environments and remote locations.
Alternative to drill ships
“Sea trials” began near Vancouver in July 2011 and the drill has been put to work commercially off Australia’s west coast by oil companies that are examining the seabed. While not in head-on competition with existing off-shore oil and gas drilling platforms, the SubSea Drill seems destined to benefit the oil and gas industry.
With a per-unit price in the $5-million-to-$10 million range, it’s not something most people will want moored at their boathouses. However, Innes foresees an ongoing demand for such equipment, not only from oil companies but also from mining and exploration companies prospecting for offshore mineralization, as well as from marine and geotechnical research institutes digging below the seafloor.
“This is one of the first platforms commercially available to truly compete with traditional geotechnical drill ships and the only one to use parented wireline technology,” says Gregg.
A further iteration of the device is in the works. Demand is unlikely to reach the point where it tempts MARL to give up manufacturing drills for land-based applications, but the company now knows that tackling a SubSea Drill application is not beyond its depth.
Nordahl Flakstad is an Edmonton-based freelance writer. Contact him at email@example.com.
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This article appears in the September/October issue of PLANT WEST.