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ultimately fows into the Williams- to make subsea tieback technology a any other options we were consider- owned Grand Isle 115 platform. good choice for the company. ing. And third, for Delta House, a “We also participate in Green LLOG chose subsea tieback tech- new development which we operate

Canyon 448, also known as Con- nology rather than using dry trees for ArcLight Capital Partners and dor, and Green Canyon 141, which for its Who Dat feld for several rea- is under construction right now,

Eyebrow also use subsea tiebacks,” says Rick sons. “First, we didn’t feel that the we also chose to go with a wet-tree

Subsea Tiebacks

Fowler, vice president of deepwater intervention savings were going to solution because we plan to cen- projects for LLOG. be worth it to build a dry-tree solu- trally locate that foating production

In the past, LLOG used subsea tion,” he says. “Second, we bought system between three other felds tiebacks because many of its pros- the Who Dat foating production that will be tied back.” pects would not support their own system on spec, so it was already Typically, LLOG uses Super Du- foating production systems, he built and we were able to get it on plex or 19D Duplex stainless steel says. Today, other metrics continue production a year earlier than with umbilicals in its systems, and most of its umbilicals are static. “We do have a couple of dynamic umbili- cals that typically involve a number of tubes and some quads. In general, our preference is to use proven technology wherever possible.”

LLOG has an alliance with FMC

Technologies to provide LLOG’s control systems for all of its subsea projects. Many operators bid out among multiple providers of control systems, but LLOG sees an advan- tage with sticking with FMC. “We consider that an advantage because we can learn one system and we

SUCTION PILE have one set of contacts with our suppliers. If there is a problem, we are very familiar with the system because we use it everywhere,” said

Fowler.

LANDING

ON TARGET

Flow assurance

The company also spends

Within 9" of the target in

InterMoor provided heave signifcant time on fow assurance, compensation services using 4,85'of water within a which is one of the big challenges 1 the compensated anchor- with long subsea tiebacks, he 48-hour period.

handler subsea installation says. LLOG’s Grand Canyon 448 feld is connected with a 34-mile method (CASIM) for installation umbilical—the second longest oil of a subsea foundation and subsea tieback in the world.

manifold within a 48-hour “When it comes to fow assur- period. When precise package ance, we have to worry about wax, control is required and asphaltenes and hydrates,” says your schedule is tight,

Fowler. “With Grand Canyon 448,

InterMoor delivers. we are blessed with good fuid with

Mooring • Foundations • Subsea very small wax content. Otherwise

That’s Subsea Expertise. it would be extremely diffcult, if

Operational Know-How.

[email protected] not impossible, to maintain fow www.intermoor.com/subsea and temperature above cloud point at ambient sea temperature.”

Visit booth #555 · OTC · May 6-9

As a further preventative measure

AngOlA – BrAzIl – EgypT – EquATOrIAl guInEA – MAlAySIA – MExICO – nOrWAy – SIngApOrE – uK – uSA against blockages, the company uses methanol and low-dosage hydrate inhibitors to prevent hydrates,

OE | April 2013 oedigital.comoedigital.com 7272 oe_flowlines.indd 72 4/1/13 1:59 AM