Following a few years of low oil prices and a drop in rig utilization rates, drillers remain focused on ways to improve operational efficiency and safety.
Many of the improvements to rigs are evolutionary, such as automation, remote control and sensing, and how rigs make sense of the vast volumes of data generated by sensors. The interconnectedness of all those sensors raises cybersecurity concerns, while environmental concerns have led some drillers to investigate energy-efficient methods to power their operations. Newer technology like managed pressure drilling (MPD) is making its mark on rigs, and a 20K drillship brings a step change to the industry.
“There’s a lot of focus on operational efficiency,” says Joseph Rousseau, ABS director for offshore exploration.
One way to vastly improve operational efficiency and safety levels is through automation such as iron roughnecks and pipe handling.
“If you can remove humans from a dangerous spot like the drill floor and do that with a robotic controlled machine, you don’t have humans in pinch points,” Rousseau says.
Remote control also makes operations safer.
“The drill floor equipment used to involve a lot of people working in that industrial area. Now it’s driven from the driller console,” he says.
More and more sensors are being built into drilling rigs and the equipment that goes on them.
“If you put in the right sensors and measurement systems, you have a better idea of the health of that asset,” Rousseau says.
Knowing the health of an asset is vital for condition-based monitoring and makes it possible to move away from the calendar-based monitoring that may require looking at every piece of machinery once a year and tearing it apart at certain intervals.
“The drilling rig is there to drill,” he says. “You want to minimize that nonproductive time, the time you’re not spending drilling that hole or moving onto the next one.”
Sensors can monitor temperature, pressure and vibration among other things. There’s a continuum of digital sophistication, he says, which moves from piecemeal monitoring to real-time monitoring.
“You can get flooded with data and not know what to do with it, or have no data at all. Neither is a particularly good place,” he says.
Big data, analytics and computer modeling can parse incoming data in real time to generate alarms if a machine is out of tolerance.
Smart technologies will go beyond collecting the information in real time so it’s possible to act on. Eventually, he says, the industry will be able to predict problems a month or two ahead of time so the asset manager can plan maintenance before the equipment fails.
The upshot, Rousseau says, is that information from sensors enables decision making “based on data instead of looking at a calendar and saying, ‘I guess it’s time.’ The rig spends more time working and less time doing ancillary tasks of inspecting and maintaining and documenting.”
Condition-based monitoring using remote and data-centric inspection technologies can keep a drilling rig doing the job it’s meant to do: drill. (Photo: ABS)
All that data flying through the air raises the issue of security of offshore drilling data, and a lot of the drilling contractors are thinking hard about cybersecurity to ensure the equipment they procure is cybersafe, he says.
“As you start taking data and transmitting it to shore bases, you have vendors with access and owners with access, there could be vulnerabilities in the system,” Rousseau says. “The last thing you want is a data breach that releases sensitive information.”
Drilling contractors are often looking for ways to reduce costs, and Rousseau says he’s starting to see interest in the North Sea in improving energy efficiency, such as using shore power or wind turbine power to provide electricity to the rig instead of running diesel generators. Doing so could reduce fuel and emissions.
“It’s still early days. There’s some interest in that, but it hasn’t impacted the fleet worldwide,” Rousseau says. But he does see the potential for uptake of such solutions. “If they can save money and be green, there could be something in that.”
One of the newer trends Rousseau has noticed is the move toward the use of MPD for specific deepwater wells where there is a tight gradient between the fracture pressure and the pore pressure. Seadrill and Transocean are two drilling contractors who are using MPD systems.
“There are several rigs with an MPD system installed, and some are MPD-ready,” he says. “It allows you to access holes you might not get to otherwise.”
Getting a drilling rig to MPD-ready status requires a risk assessment, pipe routing and scheduling. MPD systems can be retrofitted onto an existing system or designed into a new system.
The industry has steadily moved into increasingly high temperature, high pressure (HTHP) reservoirs, which requires new technologies to be developed and qualified to handle the challenging reservoirs.
The industry is qualifying 20,000 psi technologies, and a 20K system has been designated for a drillship that will be used in the Gulf of Mexico. At the end of 2018, Transocean said it signed a five-year drilling contract with Chevron for one of its two dynamically positioned ultra-deepwater drillships currently under construction at Sembcorp Marine’s Jurong shipyard in Singapore. The floater will be the first rated for 20K operations and is expected to start operations in the Gulf of Mexico in the second half of 2021.
“[20K] is a limited area now but it’s an exciting area of technology,” Rousseau says. “It’s a step out from what we’ve done before.”
There have been other changes in rig design as drilling needs and abilities evolve, such as materials and more blowout preventers in a stack, he says. Most rigs have greater derrick capacity than in the past, which allows them to drill deeper.
In the end, drilling contractors are relying on constantly evolving and improving technology to drill the wells.
“They’re trying to do the same job, but with a closer eye on getting the job done correctly, quickly and still safely,” he says.
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