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Clever completions concepts, with Kvaerner and HOE, to

Technology is also helping to optimize bring such bene? ts. completions and signi? cantly reduce the “Compared to current wet tree systems, cost, May says. dry tree systems can improve reservoir

In the Gulf of Mexico, where the lower management and reduce well interven- tertiary reservoirs have low permeability, tion, resulting in increased rates and achieving high fracture rates requires recoveries,” May says.

fracture stimulation, he says. “Thick According to DeepStar’s database, for intervals require 3-5 frac packs.” Gulf of Mexico Miocene developments,

In 2007, Chevron teamed up with dry trees can offer a 5% incremental

Halliburton to design and build a new recovery, or in some cases, as much as a system – an enhanced single trip multi- 20% incremental recovery, “which is a zonal completion system. It is a downhole very signi? cant prize,” May says. completion system, which includes a “Incremental recovery in Wilcox

CHAIN STOPPERS CHAIN STOPPERS

Schlumberger insider perforating gun to reservoirs is estimated as a bit lower at minimize shock and debris, that enables 3-5%, but this is still a very signi? cant

Chevron to stimulate and gravel pack thick prize. This is a result of the lower well multiple completion zones in a single trip. costs, which enables more wells to be

The completion challenges in a lower drilled, with tighter well spacing, and tertiary trend are the combined reservoir also provides lower costs for in? eld pressures, and 1400ft interval lengths, interventions.”

May says. Yet, using this system has “Chevron leads the industry in enabled Chevron not only to be more maturing two promising dry tree ef? cient, but also save costs. semisubmersible concepts,” May adds. “Halliburton’s enhanced single trip “Semisubmersibles do not have the pay- multi-zonal completions are an example load restrictions of the Spar, or the water of deploying a new technology that took depth limitations posed by a tension leg early vision, early commitment and early platform. Direct access to wells will limit partnership nearly 10 years ago,” May dependence on mobile offshore drilling says. “After the Jack and St. Malo discov- units. Quayside integration would reduce eries in 2003 and 2004, we realized we costs and schedule risks.” would need a step change in our comple- The dry tree semi could be a technical tion practices to reduce the cost. enabler, when large payload and water “So far we’ve used that single trip depth are required, perhaps a commercial system on four completions, we’ve seen enabler for marginal ? elds when increas- savings of approximately $150 million, ing recovery rates and reducing costs

UNDERWATER FAIRLEADS UNDERWATER FAIRLEADS when compared to the conventional com- associated with drilling, completion and pletion methodology,” May says. “We’ve intervention of subsea wells are key to successfully executed the technology commercialization, he adds.

for both the cased hole and openhole

Reducing costs systems, and we veri? ed that we’ve had quality completions through a drill stem Records continue to be set around the ? ow test on two of the completions, one world as the industry explores deeper in Jack and one in St. Malo.” prospects, May says. “Costs need to be

Intelligent well completions providing reduced,” May says. “Using technology zonal control and sand face monitoring to reduce the time it takes to achieve offer further potential. They can help completions is helping Chevron.

TURNDOWN SHEAVES/ sustain and improve recovery factors on “We have moved from bigger to

CHAIN STOPPERS secondary and enhanced oil recovery smarter developments and we need to projects, May says. continue towards smarter. Technology

DESIGNS FOR ALL LOAD MONITORING

Chevron successfully installed intelli- needs to deliver cost reductions to cre-

CHAIN & WIRE SIZES CHAIN & WIRE SIZES SYSTEMS AVAIABLE gent well completions on subsea wells on ate further for ? eld developments and its Gulf of Mexico Tahiti project. “Next, improve competitiveness on existing

ABS, DNV, LR, BV PRE-TENSIONING we want to install these on lower tertiary assets. Producing assets will need less

APPROVALS SYSTEMS completions with their even higher reser- complex incremental technology with voir pressures,” May says. immediate impact. We need to look

COMMISSIONING & CUSTOM DESIGNS out at what other industries are doing

START-UP FOR ALL

Dry trees - lower drilling costs and overcome resistance to things ‘not

SERVICES CONDITIONS

Dry tree concepts could also save cash invented here.’ In areas where intellec- and make drilling and intervention easier tual property is less sensitive or the price www.smithberger.com and cheaper he says. Chevron is work- is so large it is to everyone’s advantage to ing on two dry tree semisubmersible work together.” oedigital.com December 2014 | OE 31 028_OE1214_D&C1.indd 31 11/21/14 3:26 PM