Installed in 350-ft caissons where cyclonic separation takes place, pumping systems can move up to 125,000 b/d while helping conquer extreme back, spar riser head pressures

Because the Perdido Regional Development involves three widely spaced, ultra-deepwater fields whose reservoirs are made up of older rock with tighter porosity and permeability along with low temperatures and pressures, Shell Exploration and Production (Shell) decided early on to handle all production via equipment placed on the sea floor, including artificially lifting production liquids to the Perdido spar topsides from a water depth of more than 8,000 ft (2439m).

Under this accelerated production plan, Shell would route the gathered oil and natural gas from 35 subsea completions – including 22 wet-tree, Direct Vertical Access (DVA) wells clustered beneath the Perdido spar itself – through two seafloor manifolds and then into five separate vertical processing and boosting stations, each installed on the sea floor in close proximity to the spar and each armed with a powerful electrical submersible pumping (ESP) system.

Baker Oil Tools’ MPas one-trip isolation packers are the industry’s only non-inflatable mechanical packers that conform to irregular wellbore geometries.

For this vital system, Shell in December 2006 chose Baker Hughes Centrilift and its innovative array of enhanced ESP run life subsea production solutions. Other Baker Hughes products, including a number of Baker Oil Tools downhole safety and production management and monitoring products, are being installed during completion of the subsea wells, which is still ongoing.

The Centrilift ESPs, however, would be set just below the mud line inside five pre-drilled, 350-ft (92-m) deep, 36-in (91-cm) diameter caissons directly connected to the spar’s production risers. There, cylindrical-cyclonic separation and ESP boosting would take place. The caissons, lowered into five so-called shallow “dummy” wells, and the ESPs, each encased in a pressure vessel with an inlet/outlet connection system on top, would be installed by a construction vessel to await first production.

Combined, the 10-in. diameter,1,600-hp ESPs are capable of delivering up to 125,000 b/d of oil and associated natural gas from the Perdido fields – Silvertip, Tobago and Great White – to the spar topsides.

The Perdido seafloor production handling setup is the world’s deepest application of a full host-scale subsea separating and boosting system, and will remove fluid back pressure on the wells, particularly those completed at Silvertip and Tobago, which will reach the processing/boosting system in lengthy 10-in. (25-cm) seafloor flow lines, some up to 30 miles (48 km) or more in length.


ESPs the only subsea boosting system qualified for ultra-deepwater


As noted, Perdido Regional Development wells tap older Paleocene reservoirs, which exhibit sub-normal flowing tubing head pressures – about 750 psi – compared to younger Gulf of Mexico pools. However, once arriving directly below the Perdido spar, the fields’ multiphase flow will be confronted with a head pressure exerted by 8,000 ft of fluid in the risers, hence the need for artificial lift. ESP systems were chosen for this project because they were the only subsea pumping systems designed to operate at these water depths and corresponding pressures.

In caisson separation, the multiphase fluids are conditioned in the inlet piping and enter the caisson at a downward angle and at a tangent, which causes the fluids to disengage from the gas. Gravity, in turn, causes the separated gas to travel upward inside the production riser tubing annulus. Meanwhile, the tangential velocity inside the caisson keeps the oil/water fluids from re-entraining with the gas, which swirl downwards to the bottom of the caisson, where the ESP then pumps them through dedicated tubing inside the production riser for topsides handling.

Whatever the horsepower/pump rating, Centrilift ESPs are specifically designed to handle high gas volume fractions (GVF). This is particularly important for seabed boosting systems, where gas content can be significant, such as at Perdido. The multiphase pump technology includes the ESPs’ patented split-vane impeller design, which is key to keeping gas from accumulating in the pump and locking it. Under certain circumstances, Centrilift ESPs can handle up to 70% GVF without gas locking.

Subsea separation/boosting exhibits a number of enhanced run life benefits. For example, once the gas is removed from the flow stream, the heat retained in the fluid phase, coupled with the high flow capacity of the ESP, helps prevent hydrate formation. For that reason, Shell did not specify physical heating elements for the Perdido caissons or pumps.

Baker Hughes’ multi-phase pump technology includes ESP split-vane impeller design.

However, Shell did award Baker Hughes with the contract for chemical engineering and design services, with a list of deliverables that included flow assurance, monitoring and surveillance, chemical injection, chemical product development and others. Baker Hughes also was awarded with the first fill contract in 2009, along with a one-year contract to supply chemicals and chemical services.


SURELIFT gauges, monitoring tools


Each Perdido ESP package is equipped with a number of Baker Hughes Intelligent Production Systems’ SURELIFT™ gauging and monitoring instruments designed to optimize output from the ESPs. All SURELIFT instruments are connected inside the ESP pressure vessel by a single mono-conductor cable to power the sensors and transfer the signal cleanly to the surface.

Among the SURELIFT sensors and gauges on each ESP package are:

  • The SURELIFT/E Pod, which connects to the bottom of the lower ESP motor and interfaces with resistance temperature device (RTD) sensors for real-time motor winding temperatures along with lower-caisson pressures/temperatures.
  • The SURELIFT/E Fixed-Venturi Flow Meter Carrier, which houses a dual gauge for monitoring real-time ESP flow rate and discharge data.
  • The SURELIFT/E Dual-Gauge Carrier, which houses a dual gauge whose lower end supplies density and temperature data and whose upper end supplies real-time pressures/temperatures from the middle- caisson level.
  • The SURELIFT/E Single-Gauge Carrier, which supplies upper-caisson level pressures/temperature.
  • The SURELIFT/E Vibration Sensor, which connects to the ESP intake pump to measure dual X and Y vibrations.


Additionally, Baker Hughes’ ESP/Intelligent Production Systems data specialists are working closely with Shell’s Perdido commissioning team to assure that all SURELIFT real-time data interface with Shell’s SCADA worldwide monitoring system.

Rounding out hardware installations for the ESP installations are the Baker Hughes ESP cable/control line cutting tool, a mechanically operated device designed to cut through the ESP cable, the tubular encased conductor (TEC) wire and chemical injection pack in the event the tubing inside a production riser must be cut and retrieved. The cutter is a critical component of a systems solution approach to intervention.

While Baker Hughes is in the forefront of subsea processing and boosting technology, it also historically has been a key provider of drilling and completions equipment and services, and continues to contribute significantly to preparing Perdido wells for production.


One trip, multiple sampling


In the realm of formation evaluation, Baker Hughes is providing new downhole tools designed to record formation pressures and collect multiple, high-purity samples of formation fluid types and behaviors and then deliver the data to the surface in real time, all in a single trip of the tool array.

Chief among those being utilized in Perdido wells is the Reservoir Characterization Instrument™ (RCI) string, a wire line-conveyed package that takes large-volume, early development samples of well fluids, along with formation pressures and temperatures, and takes them during only one trip into the hole.

The RCI tool can be configured with a straddle sealing array, which employs a modular design for operational flexibility. This overcomes limitations placed on the standard probe configuration in fractured, vuggy and tight-borehole formations. The twin inflatable sealing elements are set in the borehole mud cake wall to isolate a 1-m (3.3-ft) test section, exposing a larger sampling area that requires less draw down.

The Baker Atlas IFX tool has transducers for measuring fluid density, viscosity and sound speed. The optical sensor array provides light absorbance spectra, UV fluorescence spectra, and a continuous refractometer.

Included in the RCI string being used in Perdido wells is Baker Hughes’ new In-Situ Fluids eXplorer™ tool, which monitors the real-time physical properties of the fluids being pumped from the formation through the RCI tool. This tool also takes samples in volumes that total up to 4.8 quarts (4.5 liters) and holds them in multiple sealed carriers for later hands-on examination. This capability far exceeds that of traditional wire line formation test tools, which are capable of taking only a few, sometimes highly contaminated formation fluid samples.

Other RCI tool applications include vertical interference testing, rock strength determination and cased-hole testing and sampling.


SCSSVs, real-time completion measurements


For well completions, Baker Hughes is supplying Perdido wells with Neptune™ nitrogen-charged, tubing-retrievable surface controlled subsurface safety valves (SCSSV), which feature innovative non-elastomeric seal technology – an industry first for nitrogen-charged valves.

Additionally, for the 22 subsea completions in the Great White field, Shell chose Baker Oil Tools’ MPas™ one-trip mechanical isolation packers, the industry’s only non-inflatable mechanical packer that conforms to irregular wellbore geometries.

Run as an integral part of the casing or liner string, the MPas packer uses an elastomeric element with composite structure that is hydraulically set. Shifting a balance sleeve allows wellbore hydrostatic pressure to act against an atmospheric chamber, which applies the setting force. A lock mechanism maintains the setting force for the life of the well, even if hydrostatic pressure is removed.

Also, as part of well completion hardware, Baker Atlas ran cement bond integrity measurements using its segmented bond tool (SBT), which provides 360-deg. evaluation of cement bonding to identify any channels in the cement annulus which could result in a poor hydraulic seal and, conversely, find zones of uniform bonding across only a few feet of casing. The data can help avoid costly squeeze cementing procedures.

The Baker Oil Tools Neptune series nitrogen-charged tubing-retrievable surface-controlled subsurface safety valve is designed for completions requiring low operating pressures due to control system limitations.

For ease of interpretation, SBT measurements are displayed in two log presentations, both of which are available in the logging mode as the data are acquired, processed, and plotted in real time.

Finally, on some Perdido wells, Baker Hughes completion engineering specialists are running Real-Time Compaction Imaging (RTCI) logs, which use fiber-optic sensors to monitor sand screen and casing deformation. The RTCI service was co-developed by Baker Hughes and Shell.

Because undetected completion deformations can lead to costly workovers, lost production, and even the potential of loss of the entire well, Shell took advantage of the RTCI technology, which uses thousands of sensors incorporated within the sand screen instrumented with optical fibers to monitor strain and acquire a 3D, high-resolution deformation image of the screen in real time.

Shell plans to re-run compaction logs throughout the life of the wells.

Baker Hughes
2929 Allen Parkway
Houston, Texas 77019
Tel: 713-439-8135 • Fax: 713-439-8600

Related Articles

Fabricating the Single-Lift Topsides

07/01/2010 The Perdido team faced a tough decision. A conventional topsides design required a series of modules that would have to be fabricated onshore, then...

Technology and Teamwork Achieve World Class Success for Shell Perdido

04/01/2010 In the high-risk ultra deepwater environment, success depends on two key components: technology and teamwork. Shell and Technip have applied innova...

The Bayou Companies provide welding, coating and insulation services around the world

04/01/2010 Straight on the heels of successfully fabricating and supplying pipe line end terminals (PLET) for Shell’s Ursa/Princess waterflood project, ...

Oceaneering Installs Record Diverless Deepwater HOOPS Tie-in

04/01/2010 Who would cut a perfectly good pipeline? Oceaneering worked with Shell to add a new tie-in for the Perdido oil export pipeline to the currently ope...

Kiewit Offshore Services experience and no surprises approach results in quality services for the offshore oil and gas industry

04/01/2010 KOS’ extensive experience in fabricating large, complex topsides enabled the company to meet the challenges associated with the multi-discipl...

Noble Corp.’s innovative engineering helps Shell to develop Perdido

04/01/2010 Long before the industry dared to dream that operating in the ultra-deepwater of the U.S. Gulf of Mexico could be possible, Noble took a bold and p...


04/01/2010 Two extremes define Perdido’s early development wells: The water is very deep, and the reservoirs are very shallow below the mudline. The dif...

H&Ps Rig 205 ready for Perdido Spar drilling, completions, interventions


With special modifications, 20,000-ft SCR rig to tackle subsea wells located in up to 9,627 feet of water


04/01/2010 As many as 220 people per shift came to work aboard the Perdido deepwater spar during the peak of commissioning and hookup, but it was a short comm...
White Papers

Transforming the Oil and Gas Industry with EPPM

With budgets in the billions, timelines spanning years, and life cycles extending over decades, oil an...
Sponsored by

Asset Decommissioning in Oil & Gas: Transforming Business

Asset intensive organizations like Oil and Gas have their own industry specific challenges when it com...
Sponsored by

Squeezing the Green: How to Cut Petroleum Downstream Costs and Optimize Processing Efficiencies with Enterprise Project Portfolio Management Solutions

As the downstream petroleum industry grapples with change in every sector and at every level, includin...
Sponsored by

7 Steps to Improve Oil & Gas Asset Decommissioning

Global competition and volatile markets are creating a challenging business climate for project based ...
Sponsored by

The impact of aging infrastructure in process manufacturing industries

Process manufacturing companies in the oil and gas, utilities, chemicals and natural resource industri...
Sponsored by

What is System Level Thermo-Fluid Analysis?

This paper will explain some of the fundamentals of System Level Thermo-Fluid Analysis and demonstrate...

Accurate Thermo-Fluid Simulation in Real Time Environments

The crux of any task undertaken in System Level Thermo-Fluid Analysis is striking a balance between ti...

6 ways for Energy, Chemical and Oil and Gas Companies to Avert the Impending Workforce Crisis

As many as half of the skilled workers in energy, chemical and oil & gas industries are quickly he...
Sponsored by
Available Webcasts

On Demand

Global LNG: Adjusting to New Realities

Fri, Mar 20, 2015

Oil & Gas Journal’s March 20, 2015, webcast will look at how global LNG trade will be affected over the next 12-24 months by falling crude oil prices and changing patterns and pressures of demand. Will US LNG production play a role in balancing markets? Or will it add to a growing global oversupply of LNG for markets remote from easier natural gas supply? Will new buyers with marginal credit, smaller requirements, or great need for flexibility begin to look attractive to suppliers? How will high-cost, mega-projects in Australia respond to new construction cost trends?


US Midstream at a Crossroads

Fri, Mar 6, 2015

Oil & Gas Journal’s Mar. 6, 2015, webcast will focus on US midstream companies at an inflection point in their development in response to more than 6 years shale oil and gas production growth. Major infrastructure—gas plants, gathering systems, and takeaway pipelines—have been built. Major fractionation hubs have expanded. Given the radically changed pricing environment since mid-2014, where do processors go from here? What is the fate of large projects caught in mid-development? How to producers and processors cooperate to ensure a sustainable and profitable future? This event will serve to set the discussion table for the annual GPA Convention in San Antonio, Apr. 13-16, 2015.

This event is sponsored by Leidos Engineering.


The Future of US Refining

Fri, Feb 6, 2015

Oil & Gas Journal’s Feb. 6, 2015, webcast will focus on the future of US refining as various forces this year conspire to pull the industry in different directions. Lower oil prices generally reduce feedstock costs, but they have also lowered refiners’ returns, as 2015 begins with refined products priced at lows not seen in years. If lower per-barrel crude prices dampen production of lighter crudes among shale plays, what will happen to refiners’ plans to export more barrels of lighter crudes? And as always, refiners will be affected by government regulations, particularly those that suppress demand, increase costs, or limit access to markets or supply.


Oil & Gas Journal’s Forecast & Review/Worldwide Pipeline Construction 2015

Fri, Jan 30, 2015

The  Forecast & Review/Worldwide Pipeline Construction 2015 Webcast will address Oil & Gas Journal’s outlooks for the oil market and pipeline construction in a year of turbulence. Based on two annual special reports, the webcast will be presented by OGJ Editor Bob Tippee and OGJ Managing Editor-Technology Chris Smith.
The Forecast & Review portion of the webcast will identify forces underlying the collapse in crude oil prices and assess prospects for changes essential to recovery—all in the context of geopolitical pressures buffeting the market.


Careers at TOTAL

Careers at TOTAL - Videos

More than 600 job openings are now online, watch videos and learn more!


Click Here to Watch

Other Oil & Gas Industry Jobs

Search More Job Listings >>
Stay Connected