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Automated drilling rig
designed for Schrader Bluff
Kristen Nelson
As BP Exploration (Alaska) Inc. looks for ways to minimize environmental impacts, enhance worker safety and reduce development costs at Schrader Bluff, a lightweight automated drilling system, or LADS, is part of the answer.
David Jenkins, BP’s viscous oil team leader, told PNA in a February interview that conventional wells drilled in 1998 at Schrader cost about $2.5 million. “And for your $2.5 million, you’d get a 300 barrel-a-day well.” The multi-lateral horizontal wells the company is drilling now at Schrader cost about $4 million, he said, with production in the 1,000 to 1,200 BOPD range.
To meet Schrader development objectives of driving down the cost of drilling by up to 30 percent, BP started looking for new drilling technology. “And that’s where we get to the light automated drilling system, known as LADS,” Jenkins said.
The LADS is designed to be able to travel over frozen tundra with minimal impacts and damage — and without an ice road.
It will also “dramatically automate the whole drilling system and reduce the rig crews in half from what we currently need to drill a well”. The LADS rig will also integrate some third-party contracting technologies, like cementing and measurement while drilling (MWD) services, Jenkins said.
The LADS has about a third the footprint of a conventional rig, but “because of its state-of-the-art equipment, it actually should be almost as fully capable as the biggest rig,” Jenkins said. Slant rig idea from Canada BP looked at drilling rigs in Canada, and the depths to which those rigs drilled.
“And the real question is, what does it really take to drill in the Arctic, in Arctic conditions?” Jenkins said. The LADS uses Canadian rig technology and state-of-the art automation “designed both to improve its environmental characteristics as well as increase its overall health and safety performance.”
The LADS is based on slant-well technology, Jenkins said. The ‘mast’ of the LADS is two rails — so the rig lacks the conventional mast of lattice work and four legs. That difference takes a lot of the steel out of the rig, he said, making it a lot lighter, because those heavy-duty masts not only add to the weight, but also require a huge substructure to support the mast.
The draw works on a typical rig goes up and down like a big pulley system, whereas on the LADS, the draw works goes up and down on the two rails. The LADS is based on a Canadian system for drilling wells at a slanted angle: Instead of drilling straight down and then kicking off to the side, the rig itself is slanted so the drilling is at an angle from the beginning.
The LADS will have a top head rotary drive. It also has an automated pipe handling system, Jenkins said. The drill pipe and casing will be loaded into pipe magazines or cassettes at the steel mill or pipe yard. A computer controlled, hydraulically operated pipe handling system will then retrieve the drill pipe or casing and securely elevate the pipe joint into the mast / derrick, where an automatic or ‘iron’ roughneck will screw the new piece of pipe onto the existing string.
“The majority of the work can be handled by one or two, almost in effect by an operator and some helpers,” Jenkins said. Rig includes some service equipment With current cementing technology, a cementing service company brings their big pump trucks and special equipment and mixers and trained personnel to the rig. With the LADS, “a lot of the equipment is being built into the rig. And so we’ll need to just get the cement and some expertise.”
Some of the service companies are collaborating on the LADS, which is being built by Phoenix Alaska Technology, a subsidiary of multinational Nissho Iwai Corp., a major supplier of steel products (drill pipe, casing and tubulars) to BP in Alaska.
The LADS rig design, integrated systems and focus on health, safety and environmental factors is designed to get us to the next phase in the drilling technology, Jenkins said.
“And it is unproven, although, actually, if you look at the individual components, 90 percent of the individual components are actually current technology. But the way it’s being put together is kind of unprecedented.”
A lot of what’s being done for the LADS, Jenkins said, is “taking technology from totally different applications and bringing them on to a land-based drilling rig where it normally doesn’t exist.”
“But because it is really new technology, the real question for us is will we have worked the bugs out of it by then? And that’s certainly our goal. But we haven’t proven it yet,” he said.
The rig is under construction at the Heartland Rig International fabrication facility in Brady, Texas, and is scheduled to be in Alaska at the end of August.
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