Subsea WellheadsFor deep and shallow water applications

Certified System ComponentsTMP R E S S U R E

The Cameron family of STM™and STC™

subsea wellheads delivers the economicbenefits of modularity and the perfor-mance benefits of advanced design.These benefits mean faster delivery, easier installation and reduced costs innearly every subsea drilling application.And that is especially important fortoday’s deepwater challenges.

With modularity at the componentlevel, there are no performance trade-offs. Cameron subsea wellheads containtechnology found nowhere else andreflect the depth of our pressure controlexperience. The STM wellhead, forexample, demonstrates our no-compro-

mise design approach with parallel boremetal seals, better connection optionswith BOPs and Christmas trees andinterchangeable components.

A selection of running tools (includingthe unique CHSART tool - see page 7)and ancillary equipment is also part ofthe highest performing subsea wellheadsystems in the world’s offshore oilfields.

Single Trip Metal Seal SubseaWellhead SystemThe STM wellhead reduces drilling costsby eliminating unnecessary trips whileproviding the most advanced pressurecontrol technology, at any depth, in any

For more than seventy-five

years, the leader

Cameron’s experience in pressure control

can be traced back to 1922. The introduc-

tion of the first BOP that became an indus-

try standard began an unequaled history

of innovation. Type “A” casing hanger,

All-Welded Body Ball Valve, first subsea

wellhead completion, the legendary U BOP,

first hydraulic production controls system,

first guidelineless drilling system, first free-

standing riser system — these are just a

few familiar milestones along Cameron’s

path of leadership.

This leadership continues today

with such innovations as the SpoolTree™

Christmas tree and the MOSAIC™ (Modular

Subsea and Integrated Completions)

Production System.

More advances are on the horizon.

As the industry pushes into new frontiers,

we’ll be there, as always, with the

technology to do it right.

Cameron’s most advanced, field proven pressure-control technology ispre-engineered into the STM wellhead.

Three connectionoptions (mandrel,hub and DWHC)

Angled shoulderprevents debrisaccumulation

Optional passivelyactivated, preloadedlockdown

Interchangeableparallel bore metalseal assemblies on13-3/8”, 10-3/4" (or 9-5/8”) and 7-5/8” (or 7") casing hangers

High strength landing shoulder on 18-3/4” housing

High pressure 18-3/4” housing

Optional 16” casinghanger available forsix-string programs(see page 5)

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1962: The industry’s first subseawellhead completion is a CameronChristmas tree in the Gulf of Mexico.

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Pre-engineered subsea wellheads from Cameron: fewer trips, lower costsand better sealing in shallow or deep water drilling operations.

environment. Central to STM wellheadperformance is Cameron’s parallel boremetal (PBM) seal technology, completelydifferent from competing tapered boredesigns and far superior.

The STM wellhead is perfect for mostsubsea drilling and production applica-tions with working pressures up to15,000 psi WP, on single wells, multi-well templates or TLP operations.Versions of the STM are available forshallow or deep water, and it is adapt-able to casing programs with five or sixstrings. Only four tools are required torun a five-string STM system.Three BOP and Christmas tree

connection profiles. Depending onyour requirements, choose from a hub, mandrel or Cameron’s new deepwater,high-capacity (DWHC) profile on thehigh-pressure 18-3/4" housing. Cameronis offering the DWHC profile to the petro-leum industry without charge, to pro-

mote standardization among deepwaterproducers and equipment suppliers.High-pressure 18-3/4” housing. Ratedup to 15,000 psi WP, Cameron’s high-pressure housing provides a parallelbore sealing surface design for the PBMcasing hanger seals. The high-pressurehousing will accommodate an optional16" casing hanger and seal assembly.Because the receptacle for the hangerand seal is welded to the bottom of thehousing or anywhere in the 20" string,

it does not add to wellhead height. Thereceptacle does not restrict a 17-1/2" bitor full-bore running equipment.

This housing has a high-strengthlanding shoulder rated to 7 million lbs.The simple, passive design allows the13-3/8" casing hanger to be reciprocatedinside the 18-3/4" housing without thepossibility of inadvertent setting. It isfully rated for H2S service.

The STM design allows all BOPtests to be performed with the wearbushings in place, saving a round tripfor each test.

Hub Mandrel DWHC

MOSAIC is the result of a design philoso-

phy that eliminates the usual tradeoffs you

expect with a pre-engineered, modular

system. With MOSAIC systems, you gain

simplified installation procedures, reduced

personnel training

and faster delivery.

Unlike ordinary systems, you don’t have

to give up flexibility, expandability and

desirable product features and benefits.

The ordinary approach to modularity

is fixed assemblies run progressively to

large structures, which are not appropriate

for many applications. MOSAIC systems

are modular at the component level,

standardized to work together in many

combinations. The result is a cost-effective

system that can be adapted to virtually any

subsea job. The MOSAIC system is more

easily expanded as

field development

needs evolve, and its components contain

the technology that provides the perfor-

mance you need.

Cameron’s subsea wellheads are

an integral part of the MOSAIC system.

They’re the perfect fit for today’s subsea

economics.

Modular Subsea And Integrated Completion systems: The MOSAIC concept

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STM wellhead undergoes seal developmenttesting at Cameron’s new, state-of-the-artResearch Center in Houston. This 55,000 sq ftresource allows us to develop and test productimprovements more quickly. In the photo atright, the STM is shown in one of our two 25 ft deep, underwater simulation tanks.

Advanced lockdown and sealing technology

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A closer look at Cameron engineeringreveals advanced but practical technol-ogy that works in the real world. Aremarkable history of pressure-controlexperience has been pre-engineered intoour subsea wellheads. You can see ourno-compromise design in these features:

Three STM wellhead-to-conductorhousing lockdown options

Passively activated, preloaded

lockdown. This locks the high-pressure,18-3/4" housing to the 30" conductorwith twelve vertical pre-load segments,in a collet finger design. This pre-loadedlockdown offers superior fatigue resis-tance. When locked down, bending andaxial loads are transferred from the BOPstack to the conductor. Fatigue loadingof the 20" casing is eliminated.Lockdown is achieved without a sepa-rate trip, and the mechanism can befully recoverable and reusable. Eight,two-inch diameter bypass holes providefor cement returns.

Passively activated,

standard lockdown.

An outwardly biased,split-metal ring is heldin position with akeeper ring. The splitring is compressed bythe inside diameter ofthe 30” conductorhousing until it islanded in a retainergroove.

High-capacity lockdown. Cameron’snew high-strength, pre-loaded lockdownis engineered for high-temperatureapplications where thermal expansion is a critical factor. This hydraulically setlockdown offers outstanding bendingresistance. It is also ideal for deepwaterapplications.

Cameron’s proprietary sealing technology

STM Parallel Bore Metal seal.

This seal is for casing hangers in the 18-3/4" high-pressure housing and isinterchangeable on 13-3/8", 10-3/4” (or 9-5/8") and 7-5/8" (or 7") hangers. It is radially engaged, bi-directional, and provides constant contact pressureon inner and outer sealing surfaces.Because the PBM seal is designed for a parallel-bore sealing surface, it provides equal seal protection frompressures above or below. The inabilityto effectively seal pressures from belowis a weakness of tapered-bowl sealdesigns offered by some wellhead manufacturers.

The Cameron parallel bore designallows for slight vertical movement ofthe seal without affecting seal integrity.During lab testing, the seal assembly wasmoved as much as 1/4" while maintain-ing full test pressure of 15,000 psi. PBMseals are rated for continuous operationin temperatures of up to 350˚F (177˚C),with excursions to 400˚F (204˚C), andcan be used in H2S environments.

The PBM seal assembly and high-pressure housing design provides fortwo additional contingency seals: anoptional elastomer seal and a metal seal

in a recessed bore. The metal seals onthe OD and ID always retain pressurebefore the elastomer seal. The elastomerseal is a true secondary seal.

PBM seals are set hydraulically withCameron’s CHSART running tool,which runs the casing hanger and sealassembly in one trip.

STC Metal-End Cap seal. Field provenin hundreds of wells, the MEC seal assembly is used in the 10,000 psi STCwellhead. Rated for temperatures up to 250˚F (121˚C), the proprietary CAMLAST™ elastomer seal element isresistant to H2S, CO2, chlorides, dieselfluid and oil or water-based amine corrosion inhibitors.

Stainless steel caps on the upper andlower surfaces of the elastomer preventextrusion, limit the elastomer’s exposureto corrosive wellbore fluids and preventseal roll-off during installation. TheMetal-End Cap seal will often workwhen ordinary seals won’t because theseal is highly tolerant of sealing surfacedamage. The seal is radially energizedand requires less energy to set than ordinary seals. Well or test pressurecompresses the elastomer, which adds to seal quality.

Unlocked Locked

ParallelBoreMetalSeals

OptionalCAMLASTInsertSeal

RecessedContingencySeal Bore

PBM Seal in running position

PBM Seal in energized position

Passively activated, preloaded lockdown

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Optional 16-inch casing hangerThe 16" hanger and seal assembly areavailable for both the STM and STCwellheads in six-string casing programs.The receptacle can be welded to the bot-tom of the 18-3/4" high-pressure housingextension or anywhere in the 20" stringso height is not added to the wellhead.The receptacle contains a passive loadshoulder with a 17-9/16" minimum ID.The shoulder is rated to 1.2 million lbs.Full-bore running tools or a 17-1/2" bitcan be used without restriction.

The 16" boll weevil style hanger andseal assembly are installed and tested ina single trip without having to pull thebore protector in the 18-3/4" housing. A CAMLAST elastomer seal in theassembly is energized to seal in the boreof the receptacle. The seal location isprotected from drill string damage.

The totally weight-set and compact STC

wellhead is a popular choice for lower

pressure wells to 10,000 psi WP. Attractive

pricing and rig-time savings during installa-

tion make it the most cost-effective well-

head in its operating range.

The STC wellhead shares some of the

same benefits as Cameron’s STM wellhead.

It has a compact design, casing hangers

and seal assemblies that can be run in a

single trip and interchangeable parallel

bore elastomeric seal assemblies. It is sup-

plied with the “passive” lockdown, which

is standard on the STM wellhead. The 18-

3/4" high-pressure housing is available

with hub or mandrel BOP and Christmas

tree connection profiles.

The STC wellhead uses Cameron’s

proprietary Metal-End Cap seals with CAM-

LAST elastomer. When setting the seals in

the STC wellhead system, the seal cannot

be completed unless the seal assembly is

locked in place correctly, eliminating the

possibility of a false test. Like the STM,

only four tools are required to run a five-

string STC system.

An optional 16" hanger can be

used in six-string casing programs. The

16" hanger and seal assembly are run

in one trip.

High-pressure18-3/4” housing

Passively activated,standard lockdown

Hub ormandrelconnectionprofiles

Cameron weight-set, Metal-End Capelastomer seals

Optional 16” casinghanger available forsix-string programs

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Single-tripcasing hangerand sealassemblies

Interchangeableseal assemblieson each casinghanger

18-3/4" Housing with16" Receptacle

Attached

DETAIL A16" Hanger and

Seal Assembly Installed in Receptacle

Single Trip Compact Subsea Wellhead System

17-13/16" I.D.

16" Receptacle

17-9/16" I.D.

16" Hanger

16" SealAssembly

17-7/8" I.D.

Seal Area18" I.D.

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DETAIL A

Guidebases and running tools

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The benefits of modularity are pre-engineered into Cameron’s remotelyretrievable/reinstallable guidebase(RRGB). Guideline or guidelineless versions of the RRGB are available.Guide posts are permitted to strokeapproximately six inches to allow BOPorientation prior to loading the post.This reduces the risk of damage whenlanding the BOP stack. Multiple guide-bases can be combined into a single,pre-tested template. Any number ofwells can be accommodated throughmultiples of the guidebases. Multi-wellunits allow wellbores to be spaced asclosely as 7-1/2 ft on center.

Cameron STM/STC Running ToolPackage and ancillary equipmentThe Cameron STM and STC RunningTool Package includes the tools requiredto run a five-string STM or STC system.All these tools are simple to make upand all release with right-hand rotation.• Retrievable/reinstallable guidebase

running tool; • 30" housing running tool; • 18-3/4" housing and BOP test tool;• Casing Hanger Seal Assembly Running

Tool (CHSART) to install casing hang-ers and seals and perform seal tests;

• Wear bushing running/retrieving tool.

CHSART (Casing Hanger SealAssembly Running Tool)Cameron’s advanced wellhead technol-ogy includes running tools that con-tribute to system cost savings and easeof use. The CHSART tool is a perfectexample. In the STM system, it allowsinstallation of casing hangers and PBMseal assemblies in one trip. The tool isthen used to hydraulically set the casinghanger seal assembly in a unique way.Unlike ordinary systems, which set theseals by pressurizing the BOP stack topump the seal down, the CHSART toolsets the seal assembly by pressurizingdown the drill pipe. This allows the sealto be set before stack pressure isapplied. After the seal is fully set and inposition, the seal is tested using theCHSART tool with stack pressure.

The STM spring-loaded locking mechanismautomatically locks the 30” conductor housingto the guidebase.

Casing hanger seal assembly is set by pressuring down the drill pipe, which allows the seal to be set before stack pressure is applied.

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Ancillary equipmentCameron’s STM/STC Running Tool Packagesare normally all that’s required to run five-string systems under most conditions. In addi-tion, Cameron offers a complete line of special-purpose tools: • Jetting tool• Boll weevil test tool with redundant seals• Weight-set BOP tester• One-trip Seal Assembly Retrieval Tool (SART)• Temporary abandonment (TA) caps• Emergency drill pipe hang-off tool• Full-bore casing hanger running tools• Hydraulic 30" running and tieback tool• Casing hanger cleanout tool• 30"/36" housing drill-ahead tool• 18-3/4" housing retrieval tool• Shallow water flow shutoff systems• Tieback system• CAMSMART™ downhole measurement tool

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CHSART Multipurpose Running Tool

Running Toolfor 18-3/4" Housing

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In a single trip, the Casing Hanger Seal AssemblyRunning Tool runs each casing hanger and sealassembly and hydraulically sets the seal.

After running the high-pressurehousing, this tool is used to testthe BOP. A position indicator rodprovides visual verification oftool lock/unlock.

30” STM Conductor HousingRunning Tool

The 30” conductor housing running toolis cam-actuated and has a non-risingstem. Only 6-1/2 rotations fully make upand release the tool.

Wear Bushing Running andRetrieval Tool

This is the only tool needed to set orretrieve all wear bushings in a five-stringsystem including the bore protector.

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© Cooper Cameron Corporation, Cameron Division, Printed in USA, 7/98, HG/5M, WR6568/TC1266

Western HemisphereCameronPO Box 1212Houston Texas 77251-1212Tel 713 939 2211Fax 713 939 2620www.camerondiv.com

Eastern HemisphereCooper Cameron (U.K.) Ltd.5 Mondial WayHarlingtonHayes UB3 5ARTel 44 181 9901800Fax 44 181 9901888www.camerondiv.com

Asia Pacific/Middle EastCooper Cameron (Singapore) Pte. Ltd.No. 2 Gul Circle, Jurong Industrial EstLocked Bag Service No. 3Jurong Town Post OfficeSingapore 629560Republic Of SingaporeTel 65 8613355Fax 65 8616197www.camerondiv.com

MOSAIC, SpoolTree, STM, STC, CAMLAST and CAMSMART are trademarks of the Cooper Cameron Corporation, Cameron Division.