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Gulf of Mexico the ? eld as well as the laboratory. found soon, Kimball says. construction vessels can heft the pieces developments by advancing in incre-

On the metals side, Turbeville says the “The full process involves years, not and install them on the seabed. ments. FMC Technologies has had a 20k issue is not to ? nd new alloys that will months,” says Patrick Kimball, FMC Because there are limits on ability to wellhead for some time. Cameron has work. Existing steel and nickel alloys

Technologies spokesman, but he noted control weight while withstanding higher built a 20k blowout preventer.

should serve equipment needs. The issue is the effort has been underway since at pressures, more capable construction ves- The Gulf’s earliest Lower Tertiary validating the metals for the more challeng- least 2012. Prior to the price drop, FMC sels will be required. developments, Shell’s Perdido, started ing u-HPHT deepwater environments, and

Technologies’ estimate was 20k, 350°F up in 2010, and Chevron’s Jack/St. Malo,

The need for heavier lift vessels testing has thrown some curves.

equipment would start being installed in brought online this year, are Lower 2017 or 2018. Agreement on how to do testing, which “Redesign of all of these components is Tertiary projects whose particular char-

There are challenges that go beyond standards to apply, is as important to going to have a knock-on effect in terms acteristics allowed development with developing standards and designing and industry adoption as the materials them- of the vessels that you need to deploy it, technological advances that were more proving new production systems. selves. There is a debate over the need to the cranes on board, the things you use incremental than revolutionary.

use fracture mechanics as part of a new to lower them to the sea? oor, the rigs,” Just because a Lower Tertiary develop-

The Seals challenge design code rather than the pressure- Kimball says. ment is u-HPHT at the well bottom in

One area is elastomer seals. Existing based calculations traditionally used to There are other metals issues. Operators the reservoir doesn’t mean it will present elastomers meet current wellhead pres- validate designs. are seeing unexpected failures in high- u-HPHT conditions at the wellhead, says sure and temperature standards, no more “You need to understand the real strength, corrosion-resistant nickel steels, Sean Shafer, consulting manager at Quest than 15,000psi or 275°F. But it has been fracture toughness of the material in the even in less challenging environments Offshore Services. Combinations of exist- hard to ? nd elastomers that tolerate both prescribed environment and you need to than u-HPHT, and there is a need to over- ing equipment can solve problems.

hotter hydrocarbons and colder seawater determine, based on that fracture tough- come that concern, Turbeville says. “There are ways to mix and match,” at depths of 10,000ft. ness and the types of ? aws you could In the case of carbon manganese steel, he says.

“The challenge with those materials is have in that material, what the life of that increasing pipe wall thicknesses to with-

Next LT projects in 2016 you can either get them to work on the component will be,” Turbeville says. stand higher pressures threatens one of high side or the low side but rarely both,” There aren’t many laboratories capable the material’s advantages, ? eld weldabil- The next Gulf of Mexico Lower Tertiary says Elliott Turbeville, FMC Technologies of doing that, he says. Lots of labs can do it ity, Turbeville says. projects are scheduled to come in 2016, global materials manager. “When you get in ambient air. “Our challenge is we need “There ma y be an opportunity there to ExxonMobil’s Julia and Shell’s Stones, °F develop new alloys that are high strength and both rely on further incremental , it gets even more challenging above 350 to do it at 400°F with 180,000 ppm of chlo- to even get them to work on the high side.” rides and high H S, and that’s where the and highly corrosion-resistant,” Turbeville advances as well as carefully modulated, 2

FMC Technologies already relies on says. “And it may be we just have to get relatively small ? rst steps.

challenge comes in,” Turbeville says.

metal-to-metal seals as primary barri- One way to withstand high pressures is creative with our engineering of existing Bottomhole temperature and pressure ers, but elastomers have been valuable to build equipment with thicker, heavier alloys to ? gure out how to use them safely data haven’t been made public, Shafer as secondary or tertiary barriers. So the walls, but there is a need to keep well- in ways we don’t presently have to do.” says, but the two projects wouldn’t be problem continues to be worked, and the heads, manifolds, ? owlines and other So far, the industry has been able to proceeding if they presented insurmount- company is optimistic a solution will be components as light as possible so that sidestep u-HPHT issues in Lower Tertiary able challenges.

Still, there is caution, he says. Even in manageable conditions, there are uncer-

Chevron’s Big Foot semisubmersible ? oating production system on 14 March was towed into the Gulf of Mexico from Kiewit’s Ingleside, Texas, yard, one of tainties about the productivity of the Lower six major projects scheduled for startup in 2015. Photo from Chevron.

Tertiary. There are questions about perme- ability and porosity and, despite high bottom-hole pressures, projects require subsea boosting to accomplish production.

At Julia, ExxonMobil, which has estimated 6 billion bo in place, is reduc- ing risk by tying back to Chevron’s Jack/

St. Malo and initially aiming to produce just 34,000 b/d. Shell estimates Stones has 2 billion bo in place, but will start by producing 60,000 b/d.

More recently, BP, Chevron and

ConocoPhillips have joined together to develop the Tiber and Gila discoveries and the Gibson prospect, possibly with a single hub serving all three develop- ments, Shafer says.

“The idea is let’s put something out there that’s a bit smaller, produce from wells, see whether the production pro? le falls into our assumptions,” Shafer says. “This is really about feeling out the

Lower Tertiary.”

Both Stones and Julia involve techno- logical advance, of course. Stones will oedigital.com May 2015 | OE 105 104_OE0515_Geo1_Bruce_V2em.indd 105 4/20/15 9:53 PM