sub sea wellhead

8/18/2019 sub sea wellhead

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Subsea WellheadsFor deep and shallow w ater applications

Certif ied System Component sTM

P R E S S U R E


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The Cameron family of STM™and STC™subsea wellheads delivers the economic

benefits 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 for

today’s deepwater challenges.

With modularity at the component

level, there are no performance trade-

offs. Cameron subsea wellheads contain

technology found nowhere else and

reflect the depth of our pressure control

experience. The STM wellhead, for

example, demonstrates our no-compro-

mise design approach with parallel bore

metal seals, better connection options

with BOPs and Christmas trees and

interchangeable components.

A selection of running tools (including

the unique CHSART tool - see page 7)and ancillary equipment is also part of

the highest performing subsea wellhead

systems in the world’s offshore oilfields.

Single Trip Metal Seal Subsea

Wellhead System

The STM wellhead reduces drilling costs

by eliminating unnecessary trips while

providing the most advanced pressure

control technology, at any depth, in any

For more than seventy-five

years, the leader

Cameron’s experience in pressure control

can b e tra ced ba ck to 1922. The introd uc-

t ion of the f irst BOP that became a n indus-

try standa rd bega n an uneq ualed history

of inno vation. Type “ A” casing ha nge r,

All-Welded Bod y Ba ll Valve, first subsea

w ellhead completion, the legend ary U BOP,

first hydraulic production controls system,

first guidelineless drilling system, first free-

standing riser system — these are just afew familiar milestones along Cameron’s

path of leadership.

This lead ership con tinue s to da y

w ith such inno vat ions as the Spoo lTree ™

Christmas tree and the MOSAIC™ (Modular

Subsea and Integrated Completions)

Production System.

More advances are on the horizon.

As the industry pushes into new front iers,

w e’ ll be there, as a lways, with the

technology to do i t r ight .

Cameron’s most advanced, field p roven p ressure-contro l technolog y is

pre-engineered int o t he STM w el lhead.

Three connection

opt ions (mandrel,

hub and DWHC)

Angl ed should er

prevents debris

accumulation

Optio nal p assively activat ed, preloaded

lockdow n

Interchangeable

parallel bore metal seal assemb lies on

13-3/8”, 10-3/4"

(or 9-5/8”) and

7-5/8” (or 7")

casing hang ers

High strengthlanding shoulder

on 18-3/4” housing

High pressure

18-3/4” hou sing

Option al 16” casing

hanger available for

six-str ing program s

(see page 5)

SD016697

1962: The ind ustry ’s fir st subsea

w ellhead completion is a Cameron

Christmas tree in the Gulf of M exico.

Pre-engineered subsea w ellheads from Cam eron: few er t rips, low er cost sand bett er seal ing in shal low or deep w ater dri l l ing operat ions.


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environment. Central to STM wellhead

performance is Cameron’s parallel bore

metal (PBM) seal technology, completely

different from competing tapered bore

designs and far superior.

The STM wellhead is perfect for most

subsea drilling and production applica-

tions with working pressures up to

15,000 psi WP, on single wells, multi-

well templates or TLP operations.

Versions of the STM are available for

shallow or deep water, and it is adapt-

able to casing programs with five or six

strings. Only four tools are required to

run a five-string STM system.

Three BOP and Chri stmas tr ee

connection prof iles. Depending on

your requirements, choose from a hub,

mandrel or Cameron’s new deepwater,

high-capacity (DWHC) profile on the

high-pressure 18-3/4" housing. Cameron

is offering the DWHC profile to the petro-

leum industry without charge, to pro-

mote standardization among deepwater

producers and equipment suppliers.

High -pressure 18-3/4” hou sing . Rated

up to 15,000 psi WP, Cameron’s high-

pressure housing provides a parallel

bore sealing surface design for the PBM

casing hanger seals. The high-pressure

housing will accommodate an optional

16" casing hanger and seal assembly.

Because the receptacle for the hanger

and seal is welded to the bottom of the

housing or anywhere in the 20" string,

it does not add to wellhead height. The

receptacle does not restrict a 17-1/2" bitor full-bore running equipment.

This housing has a high-strength

landing shoulder rated to 7 million lbs.

The simple, passive design allows the

13-3/8" casing hanger to be reciprocated

inside the 18-3/4" housing without the

possibility of inadvertent setting. It is

fully rated for H2S service.

The STM design allows all BOP

tests to be performed with the wear

bushings in place, saving a round tripfor each test.

Hub M andrel 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 system s, you g ain

simplified insta llation procedures, reduced

personne l training

and fa ster delivery.

Unlike ordinary systems, you d on’t h ave

to give up flexibility, expanda bility a nd

desirable product features and benefits.

The ordina ry approa ch to mod ularity

is fixed assemblies run progressively to

large structures, which are not appropriate

for many applications. MOSAIC systems

are modular a t the component level,s tandardized to wo rk tog ether in many

comb inat ions. The result is a cost-effective

system that can be a dapted to vir tually any

subsea job. The MOSAIC system is more

easily expanded as

field development

needs evolve, and its components contain

the technology t hat provides the perfor-

mance you need.

Cameron’s subsea wellheads are

an integra l part o f t he MOSAIC system.

They’re the perfect fit for t oda y’s subsea

economics.

Modular Subsea And Integrated Completion systems:

The MOSAIC concept

SD016797

STM w ellhead undergo es seal development

testing at Cameron’s new , state-of -the-art

Research Center i n Ho uston . This 55,000 sq ft

resource allow s us to d evelop and t est pro duct

impro vement s more quickly. In the photo at

r ight , the STM is show n in one of our two

25 f t deep, underwater s imulat ion tanks.


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Advanced lockdow n and sealing t echnology

A closer look at Cameron engineeringreveals advanced but practical technol-

ogy that works in the real world. A

remarkable history of pressure-control

experience has been pre-engineered into

our subsea wellheads. You can see ourno-compromise design in these features:

Three STM wellhead-to-conductor

housing lockdown options

Passively activ ated, p reloaded

lockdow n. This locks the high-pressure,

18-3/4" housing to the 30" conductor

with twelve vertical pre-load segments,

in a collet finger design. This pre-loaded

lockdown offers superior fatigue resis-

tance. When locked down, bending and

axial loads are transferred from the BOP

stack to the conductor. Fatigue loading

of the 20" casing is eliminated.

Lockdown is achieved without a sepa-

rate trip, and the mechanism can be

fully recoverable and reusable. Eight,

two-inch diameter bypass holes provide

for cement returns.

Passivel y acti vat ed,

standard lockdow n.An outwardly biased,

split-metal ring is held

in position with a

keeper ring. The split

ring is compressed by

the inside diameter of

the 30” conductor

housing until it is

landed in a retainer

groove.

High-capacity lockdow n. Cameron’s

new high-strength, pre-loaded lockdown

is engineered for high-temperature

applications where thermal expansion

is a critical factor. This hydraulically set

lockdown offers outstanding bending

resistance. It is also ideal for deepwater

applications.

Cameron’s proprietary sealing

technology

STM Parallel Bore M etal seal.

This seal is for casing hangers in the

18-3/4" high-pressure housing and is

interchangeable 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 pressure

on inner and outer sealing surfaces.

Because the PBM seal is designed for

a parallel-bore sealing surface, itprovides equal seal protection from

pressures above or below. The inability

to effectively seal pressures from below

is a weakness of tapered-bowl seal

designs offered by some wellhead

manufacturers.

The Cameron parallel bore design

allows for slight vertical movement of

the seal without affecting seal integrity.

During lab testing, the seal assembly was

moved as much as 1/4" while maintain-ing full test pressure of 15,000 psi. PBM

seals are rated for continuous operation

in temperatures of up to 350˚F (177˚C),

with excursions to 400˚F (204˚C), and

can be used in H2S environments.

The PBM seal assembly and high-

pressure housing design provides for

two additional contingency seals: an

optional elastomer seal and a metal seal

in a recessed bore. The metal seals on

the OD and ID always retain pressure

before the elastomer seal. The elastomer

seal is a true secondary seal.

PBM seals are set hydraulically with

Cameron’s CHSART running tool,which runs the casing hanger and seal

assembly in one trip.

STC M et al-End Cap seal. Field proven

in hundreds of wells, the MEC seal

assembly is used in the 10,000 psi STC

wellhead. Rated for temperatures up

to 250˚F (121˚C), the proprietary

CAMLAST™ elastomer seal element is

resistant to H2S, CO2, chlorides, diesel

fluid and oil or water-based amine

corrosion inhibitors.

Stainless steel caps on the upper and

lower surfaces of the elastomer prevent

extrusion, limit the elastomer’s exposure

to corrosive wellbore fluids and prevent

seal roll-off during installation. The

Metal-End Cap seal will often work

when ordinary seals won’t because the

seal is highly tolerant of sealing surface

damage. The seal is radially energized

and requires less energy to set thanordinary seals. Well or test pressure

compresses the elastomer, which adds

to seal quality.

Unlocked Locked

Paral

Bore

Meta

Seals

Opt io

CAML

Inser

Seal

Reces

Cont i

Seal B

PBM Seal in

running pos it ion

PBM Seal in

energized posit ion

Passively activated, preloaded lockdow n

SD016702 SD016703

SD016698

SD016230


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Optional 16-inch casing hanger

The 16" hanger and seal assembly are

available for both the STM and STC

wellheads in six-string casing programs.

The receptacle can be welded to the bot-

tom of the 18-3/4" high-pressure housing

extension or anywhere in the 20" string

so height is not added to the wellhead.

The receptacle contains a passive load

shoulder 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" bit

can be used without restriction.

The 16" boll weevil style hanger and

seal assembly are installed and tested in

a single trip without having to pull the

bore protector in the 18-3/4" housing.

A CAMLAST elastomer seal in the

assembly is energized to seal in the bore

of the receptacle. The seal location is

protected from drill string damage.

The to ta lly w eight -set an d comp act STC

w ellhead is a po pular choice for lower

pressure w ells to 10,000 psi WP. Attra ctive

pricing a nd rig-time savings during installa-

tion make it the most cost-effective well-

head in i t s operat ing rang e.

The STC w ellhead shares some of the

same b enef its as Cam eron’s STM w ellhead.

It has a compact de sign, casing hang ers

and seal assemblies that can be run in a

single t r ip and interchang eable pa rallel

bo re elasto meric sea l assemblies. It is sup-

plied w ith the “ passive” lockdow n, which

is sta nda rd o n th e STM w ellhead. The 18-

3/4" high-pressure housing is availab le

w ith hub or ma ndrel BOP and Christmas

tree connection profiles.

The STC w ellhea d u ses Ca mero n’s

proprieta ry Meta l-End Cap seals with CAM

LASTelasto mer. When setting the seals in

the STC wellhea d system, t he seal canno t

be completed unless the seal assembly is

locked in place correctly, eliminating the

po ssibility of a fa lse test. Like the STM,

only four too ls are required to run a f ive

string STC syste m.

An opt ional 16" hang er can be

used in six-string ca sing pro g ram s. The

16" hang er and seal assembly are run

in one trip.

High-pressure

18-3/4” h ousing

Passively acti vat ed,

standard lockdow n

Hub or

mandrel connection

prof i les

Cameron w eigh

set, Met al-End

elastom er seals

Optio nal 16” ca

hanger availabl

six-str ing pro gr

SD016696

Single-tr ip

casing han ger

and seal

assemblies

Interchangeable

seal assemb lies

on each casing

hanger

18-3/4" Housing

w ith16" Receptacle

Attached

DETAIL A

16" Hanger and

Seal Assemb ly Installed

in Receptacle

Single Trip Compact Subsea Wellhead System

17-13/16" I.D.

16" Receptacle

17-9/16" I.D.

16" Hanger

16" Seal Assembly

17-7/8" I.D.

Seal Ar ea 18" I.D.

SD016231

DETAIL A


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Guidebases and running t ools

The benefits of modularity are pre-engineered into Cameron’s remotely

retrievable/reinstallable guidebase

(RRGB). Guideline or guidelineless

versions of the RRGB are available.

Guide posts are permitted to strokeapproximately six inches to allow BOP

orientation prior to loading the post.

This reduces the risk of damage when

landing the BOP stack. Multiple guide-

bases can be combined into a single,

pre-tested template. Any number of

wells can be accommodated through

multiples of the guidebases. Multi-well

units allow wellbores to be spaced as

closely as 7-1/2 ft on center.

Cameron STM/STC Running Tool

Package and ancillary equipment

The Cameron STM and STC Running

Tool Package includes the tools required

to run a five-string STM or STC system.

All these tools are simple to make up

and 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 Seal

Assembly Running Tool)

Cameron’s advanced wellhead technol-

ogy includes running tools that con-

tribute to system cost savings and ease

of use. The CHSART tool is a perfectexample. In the STM system, it allows

installation of casing hangers and PBM

seal assemblies in one trip. The tool is

then used to hydraulically set the casing

hanger seal assembly in a unique way.

Unlike ordinary systems, which set the

seals by pressurizing the BOP stack to

pump the seal down, the CHSART tool

sets the seal assembly by pressurizing

down the drill pipe. This allows the seal

to be set before stack pressure is

applied. After the seal is fully set and in

position, the seal is tested using the

CHSART tool with stack pressure.

The STM spring-lo aded lo cking m echanism

autom atically locks the 30” conductor ho using

to th e guidebase.

Casing h anger seal assembly is set by pressuring dow n t he dril l pipe,

w hich allow s the seal to b e set bef ore stack pressure is applied.

SD016800SD016799SD016798

SD016699

Ancillary equipment

Cameron’s STM/STC Running Tool Packag

are normally all that’s required to run five-

string systems under most conditions. In ad

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 (SAR

• 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 to


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SD016705

CHSART MultipurposeRunning Tool

Running Tool

for 18-3/4" Housing

SD016701

In a sing le tri p, th e Casing Hang er Seal Assemb ly

Runn ing Tool ru ns each casing h anger an d seal

assemb ly and hy draul ically sets the seal.

Af ter running the high -pressure

housing, th is tool is used to test

the BOP. A po sit ion ind icator rod

provid es visual verif ication o f

too l lock/unlock.

30” STM Conductor HousingRunning Tool

The 30” condu ctor housing runnin g too l

is cam-actuated and has a non-ris ing

stem. Only 6-1/2 rotation s fully make up

and release the t ool.

Wear Bushing Running andRetrieval Tool

This is the only to ol needed to set or

retr ieve all w ear bushings in a five-str ing

system including t he bore prot ector.

SD10457-99

SD10480-99


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© Cooper Ca meron Corpora tion , Camero n Division, Prin ted in USA, 7/98, HG/5M, WR6568/TC1266

Western Hemisphere

Cameron

PO Box 1212

Hou sto n Texa s 77251-1212Tel 713 939 2211

Fax 713 939 2620

www.camerondiv.com

Eastern Hemisphere

Cooper Cam eron (U.K.) Ltd.

5 Mondial Way

Harlington

Hayes UB3 5AR

Tel 44 181 9901800

Fax 44 181 9901888

www.camerondiv.com

Asia Pacific/Middle East

Cooper Cameron (Singapore) Pte. Ltd.

No. 2 Gul Circle, Jurong Industrial Est

Locked Bag Service No. 3Jurong Tow n Post Office

Singapo re 629560

Republic Of Singap ore

Tel 65 8613355

Fax 65 8616197

www.camerondiv.com

MOSAIC, SpoolTree, STM, STC, CAMLASTa nd CAMSMARTare t rad ema rks of the Co ope r Camero n Corpo rat ion, Ca mero n Division.

sub sea wellhead

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