Page 110: of Offshore Engineer Magazine (May/Jun 2014)

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Pipelines

Alpha Mahatvaraj of GMC Inc. discusses how their new mechanically connected risers could ofer a potential solution for ultra-deepwater projects.

Making extremely high day rate of the specialized installation vessels. connections

Timing is a key issue

Recent presalt projects have been delayed he contribution of ultra-deep- solution for presalt risers, primarily due by riser and subsea installation assets, water developments to world to the high CO content that attacks the a rare scenario as normally the FPSO 2

T carbon steel tensile layer. Additionally, was the critical path. Component time is oil production is expected to deepwater and associated high pressures therefore a critical issue and one of the accelerate in the coming years provided that the escalating capital expenditures (internal and external) are at the limit or big potential drivers for using connec- beyond the current capability of fexible tors, which can be delivered much faster (capex) of these projects can be con- tained. A major component of the ultra- pipe. Flexible risers currently do not than fexible pipe or reeled steel spools. offer a life of feld solution and given The ICP can be installed using a 120m DP deepwater project capex is the SURF cost, particularly risers and fowlines. that these wells can produce for over 20 MSV with a modular J-lay tower using a

The current riser solutions for deepwa- years, the fexible route is a very costly connector pipeline installation proce- ter felds including fexibles and steel option for the operator. Corrosion resis- dure (C-Lay) developed by GMC. Smaller reeled or J-lay welded risers have either tant alloy (CRA) clad steel pipe addresses installation vessels such as these are limitations on service requirements or these problems, however at greatly readily available unlike the conventional have signifcant cost impact.

increased installation cost. welded J-lay options. The large special-

GMC Ltd. developed a mechanical J-lay welded and reeled SCRs have ized installation vessels have a single connector product line for risers and their own inherent problems in that line critical path and this has proved fowlines called intelligently connected installation is very costly with the a problem for major operators with pipe (ICP) to meet the emerg- delays on other projects having ing needs of the deepwater cascade effects on installation

SURF market. The connection schedules. of risers and fowlines with The ICP solution enables the pre-manufactured tubular operator to more quickly and eliminates the need for off- cost effectively produce and shore welding and high-cost manage well production. It installation and lay vessels. allows local assets to be used

The SURF installation market in SURF rather than wait- will be opened up to allow ing for the large international many potential new subsea contractors to plan the mobi- contractors to bid for projects. lization of assets from distant shores. Traditional welded

Current limitations lazy wave steel catenary riser

Flexibles manufacturers (LWSCR), freestanding hybrid

GMC’s mechanical connectors. Photo from GMC Inc.

have yet to fnd a qualifed riser (FSHR), and fexible

May 2014 | OE oedigital.com 112 112_OE0514_Pipelines2_GMC.indd 112 4/19/14 9:59 AM