F L O W C ON T R O L
Subsea Chokes
Setting the industry standard, decade after decade
F L O W C ON T R O L
The World’s Most Advanced
Subsea Chokes
Cameron’s Flow Control division provides surface and subsea choke
and actuation solutions, project management, system engineering,
operability and training.
C
ameron’s WILLIS® subsea chokes
A History of Innovation
are designed for use in production,
water injection, gas injection, gas lift
and reverse flow applications with
In 1975, Cameron manufactured the world’s
chokes ranging from 2" through 8"
nominal sizes and Cv up to 1000.
first subsea choke for the Mobil West Delta
Subsea chokes are typically used to:
design of manual surface chokes and multi-
• Start up and shut in subsea wells
• Balance pressures from different
project in the Gulf of Mexico based on the
SpoolTree™ System with
Insert-Retrievable Choke
orifice valve (MOV ™ ) trim technology.
The MOV controlled flow via two rotating
discs with circular orifices.
wells to a common manifold
Cameron offers both non-retrievable
• Reduce flowline pressures
and insert-retrievable chokes. Non-
and costs
retrievable chokes remain permanently
• Protect against reservoir collapse
attached to subsea structures, while
during startup
insert-retrievable chokes are designed
• Control flowrates to extend
so that the trim, actuator and retention
production life
mechanism can be retrieved to
• Protect subsea gate valves from
the surface.
• Plug and cage, external sleeve and
Cameron’s subsea choke trim options are
• High-pressure, high-temperature
high-pressure drops during startup
and shutdown
easily interchangeable to accommodate
Deepwater SpoolTree System with
DLRT Insert-Retrievable Choke
changing field parameters.
• Plug and cage, external sleeve or
multi-stage
• Bi-directional flow, gas injection,
gas lift, water injection (typically
multi-stage) or water alternating
Today, Cameron’s subsea chokes have
been used in more than 2000 instal-
lations around the globe and feature
leading-edge technology:
multi-stage trim styles
designs of 15,000 psi, 350º F (177º C)
• Insert-retrievable and fixed non retrievable designs
• Hydraulic stepping and stand-alone
DC electric actuation
Early WILLIS® Subsea Choke
gas (WAG)
1
Subsea HP/HT Chokes
With more than 30 years of
experience with high-pressure/
high-temperature (HP/HT) technology for surface choke applications
to bank on, Cameron brings proven
performance to the subsea domain
with its evolutionary 15,000 psi
subsea chokes.
I
n shallow or deepwater, for subsea
Christmas trees or manifolds, Cameron
has the subsea choke for the job. The
non-retrievable choke is the ideal choice
in subsea tree designs with a retrievable
flow control module or choke bridge.
For other applications, the insert-retrievable choke offers additional advantages.
In fact, Cameron’s HP/HT chokes
NON-RETRIEVABLE CHOKES
have already seen successful
The first non-retrievable subsea
service in several land and
choke was installed in 1975 and today,
platform applications with working
with over 500 of these rugged chokes
pressures of 20,000 psi and
temperatures of 650° F (343° C).
As a result, our R&D team is
developing the world’s first
20,000 psi subsea choke technology.
CC80 Non-Retrievable
Choke 7500 psi MWP
with SLCA Actuator
Cv=1000
Two basic designs
meet a variety of
requirements
installed, they are a proven,
reliable choice.
a retrievable flow control module
Permanently mounted
or choke bridge, which can also house
to a subsea structure
flow meters and instrumentation. To
such as a Christmas tree
maintain or replace the choke or trim,
or manifold, the choke
the flow control module or choke
body may also be
bridge is retrieved. These chokes are
incorporated into
usually fitted with a hydraulic stepping
or stand-alone DC electric actuator, but
CC40HP Non-Retrievable
Choke 15,000 psi MWP
with SLCA Actuator
can also be adjusted by an ROV or diver.
Subsea Non-Retrievable Choke Summary
Nom.
Size*
MWP
psi
Max
Cv**
Flow Curve
Type
Non-Retrievable Choke - Gas Lift
3"
5000
13.6
P&C EQ%
CC30FNR
Non-Retrievable Choke - Production
3"
5000
86
64
P&C Linear
P&C EQ%
CC40FNR
Non-Retrievable Choke - Production
4"
5000
256
206
P&C Linear
P&C EQ%
CC40FNR 10k
Non-Retrievable Choke - Production
4"
10,000
256
206
P&C Linear
P&C EQ%
CC40FNR HP
Non-Retrievable Choke - Production
4"
15,000
130
ES EQ%
CC40FNR
Non-Retrievable Choke - Water Injection
4"
5000
76
MS33
CC50FNR 10k
Non-Retrievable Choke - Production
5"
10,000
428
P&C Linear
CC60FNR
Non-Retrievable Choke - Production
6"
5000
544
P&C EQ%
CC80FNR
Non-Retrievable Choke - Production
8"
7500
1000
P&C Linear
Choke
Description
CC30FNR
* Nom. Size refers to the seat nominal diameter,
not the inlet or outlet end connection size.
** Reduced capacity and custom trims available.
2
P&C = Plug and Cage ES = External Sleeve
EQ%= Equal Percentage MS33= 3", Three-Stage, Multi-Stage
F L O W C ON T R O L
Subsea Insert-Retrievable Choke Summary
Nom.
Size*
MWP
psi
Max
Cv**
Flow Curve
Type
Clamp Insert Choke - Gas Lift
2"
10,000
14
8
P&C EQ%
P&C EQ%
CC30SR
Clamp Insert Choke - Gas Lift / Production
3"
10,000
46
ES Linear
CC40SR
Clamp Insert Choke - Production
4"
10,000
288
241
P&C Linear
P&C EQ%
CC40SR
Clamp Insert Choke - Production
4"
15,000
200
P&C EQ%
Single Stage
Two Stage
Three Stage
Choke
Description
CC20SR
CC40SR
Clamp Insert Choke - Reverse Flow Water
Injection (DBA multi-stage anti-cavitation trim)
4"
10,000
206
130
94
CC30SRC
Compact Insert Choke - Gas Lift
3"
10,000
80
P&C Linear
CC40SRC
Compact Insert Choke - Production
4"
10,000
224
288
P&C EQ%
P&C Linear
CC40SRC
Compact Insert Choke - Reverse Flow Water
Injection
4"
10,000
216
MS32 EQ%
CC50SR
Clamp Insert Choke - Production
5"
10,000
500
345
P&C Linear
P&C EQ%
CC40SR CLRT
Insert-Retrievable
Choke with Three-Segment
Clamp Connector
Non-retrievable choke design highlights
INSERT-RETRIEVABLE CHOKES
Insert-retrievable choke design highlights
• Pressure ratings up to 15,000 psi
Cameron supplied the first insert-
• Pressure ratings up to 15,000 psi
• Temperature ranges from -50° F to
• Temperature ranges from -50° F to
retrievable choke in 1991. Since then,
350° F (-46° C to 177° C)
350° F (-46° C to 177° C)
these highly successful chokes have
• Trim sizes from 2" through 8" with
• Trim sizes from 2" through 5" with
been installed on subsea systems in
controllable Cv from less than 1 up
Cv up to 500
varying water depths around the world.
to 1000
• Designed for 20 years of service life,
A number of insert-retention designs are
• 20-year design life, excluding wearing
excluding wearing trim elements
available, including the totally vertically
trim elements
• Meet or exceed all API 6A/17D, ISO
retrievable lightweight compact choke,
• Meet or exceed API 6A /17D, ISO
10423/13628-4, NACE MR-01-75/ ISO
with its dog-in-window connector, and
10423/13628-4, NACE MR-01-75/ ISO
15156 and NORSOK requirements
the more traditional three-segment
15156 and NORSOK requirements
clamp CLRT-style choke.
Flow Curves
Flow Curve for CC80FNR Linear Plug
and Cage Cv=1000
1200
500
1000
400
800
Cv
600
300
600
200
400
100
200
4.00
3.75
3.50
3.25
3.00
2.75
2.50
2.25
2.00
1.75
1.50
1.25
1.00
0.75
0.50
0.25
2.13
2.00
1.88
1.75
1.63
1.50
1.38
1.25
1.13
1.00
0.88
0.75
0.63
0.50
0.38
0.25
0.13
Stem Travel (in)
The world’s largest field-proven insertretrievable subsea choke with a max Cv=500
0.00
0
0
0.00
Cv
Flow Curve for CC50SR Linear Plug
and Cage Cv=500
Stem Travel (in)
The world’s largest field-proven subsea nonretrievable choke with a max Cv=1000
3
Complete Choke Resources
Beginning with complete design
services, Cameron covers the realm
of subsea choke equipment and
support to save you time, money
Exceptional options
put you in control
I
nsert-retrievable control chokes are
available with a number of retention
mechanisms, including the lightweight
vertically retrievable dog-in-window and
the three-segment clamp style.
and headaches. Whatever your
requirements and however complex
the application, count on Cameron
to provide all the products you
need to get the job done:
• Running tools
With either design, the lockdown mechanism is released from the choke body
so the trim, actuator, seals and lockdown
Dog-in-Window Connector
mechanism are retrieved to the surface
Total vertical access is achieved via
as a self-contained package for easy
push/pull rods, which engage/disengage
maintenance and trim replacement.
dogs for insert installation and retrieval,
with the option of hydraulic override
• Intervention skids
for disconnect. And, because it requires
• Marine growth/debris caps
no horizontal access, the choke can be
• Guide funnels
more centrally placed, potentially reduc-
• Spare inserts
ing the size and weight of the Christmas
tree and manifold significantly. Installa-
• Commissioning seal kits
tion is simple enough for smaller, more
• Trim change kits
readily accessible vessels to handle.
• Running tool spares kits
The compact choke features an increased
trim cavity and annular area for reduced
flow velocity and a more uniform fluid
presentation to trim. Several cage-style
Choke Insert Ship and Workover Skid
trims are available,
including plug and
cage for reverse
and forward flow
and maximum
Cv, and water
CC40SRC Compact Choke
COMPACT INSERT-RETRIEVABLE
CHOKES
Cameron’s latest innovation to its
revolutionary compact choke is a dog-inwindow connector that offers tremendous advantages: It’s 35% smaller, 45%
lighter and 100% proven. It also provides
total vertical access—with absolutely no
compromise in performance.
4
Dedicated Compact
Choke Running Tool
F L O W C ON T R O L
CLAMP-STYLE
INSERT-RETRIEVABLE CHOKES
The simple clamp mechanism for latching
the insert to the choke body is a robust,
ROV/diver-friendly system. A remotely
operated tool lowers the insert with its
clamp assembly into the choke body.
Guide pins align the insert, and hydraulic
and electrical connecters automatically
mate as the insert is soft landed. Finally,
the ROV operates a single threaded shaft
to close the clamp segments.
Subsea Manifold with Compact Chokes
CC40SR Clamp Choke
with CLRT Running
Tool Funnel
Cameron has developed configurations
injection multi-stage, the choice for long-
to allow retrieval by the Cameron
term operation in cavitation-sensitive
dedicated Clamp Running Tool (CLRT) or
conditions and reverse flow applications.
a third-party Deepwater Liftline Running
Tool (DLRT) or Multi-Purpose Running
Cameron’s reliable Subsea Stepping
Tool (MPRT).
Linear Choke Actuator (SLCA™), comprehensively tested and qualified to
CC40SR Clamp Choke
with DLRT Land
Out Interface
10,000-foot water depths, powers the
new compact choke. The number of
actuation pulses can be halved on the
open or closed cycles independently, for
either greater control or faster operation.
Retrievable Subsea Choke
with Clamp Connector
Intervention Tooling
For deepwater subsea choke applications requiring specialized intervention techniques, Cameron supplies intervention tooling, test skids
and shipping skids designed and manufactured to meet customer and
project requirements.
In addition, Cameron’s insert-retrievable chokes are compatible
with the intervention tooling currently supplied with the CAMTROL®
subsea production control system, which means the same intervention
tooling used to install and retrieve subsea control modules can also
be used with Cameron’s chokes.
Deepwater Liftline Running Tool
Deepwater Liftline
Running Tool
5
Trim Principle
Cameron’s subsea chokes feature
a control choke trim that uses
hydrodynamic energy dissipation
to reduce erosion problems and
ensure positive flow. The flow
enters the inlet and circulates in
the annulus between the body and
cage. The even distribution of
High-performance
actuators for
every purpose
C
ameron provides a variety of subsea
choke actuators, including hydrau-
lic “fail fixed” actuators in operating
pressures of 3000 and 5000 psi, which
are compatible with water or mineral-oilbased control fluids, as well as optional
stand-alone DC electric actuators.
ports around the cage determines
RD250 ROV GEARBOX
maximum flow capacity. High-velocity
Aqua-Torq™ Hydraulic Stepping Choke Actuator
For use with Cameron’s non-retrievable
jets produced by the flow collide
and the customer hydraulic interface
chokes with either diver or ROV opera-
is usually by the weld tails on the stab
in the cage center, dissipating
tion, this actuator is oil-filled and
mate hydraulic couplers.
the most erosive energy away from
pressure-compensated, and has an
the downstream components.
external marine-growth-resistant
LINEAR VARIABLE DIFFERENTIAL
local-position indicator, which allows
TRANSFORMER
the choke setting to be easily read.
An accurate Linear Variable Differential
Transformer (LVDT) electronic remote-
SUBSEA STEPPING LINEAR
position feedback sensor is available for
CHOKE ACTUATOR (SLCA)
both Aqua-Torq and SLCA actuators.
Developed for use on non-retrievable
These non-contacting position sensors
chokes and now also used on the new
are seal welded, digitally calibrated and
compact choke, the SLCA has two
available in analog (4-20mA) and digital
single-acting piston-pawl assemblies —
(CAN Bus) output designs. Reliable,
one for open and one for closed. It is
field-proven and individually hyperbari-
oil-filled and pressure-compensated with
cally tested to 11,400-foot (3475-meter)
a remote-position feedback via an LVDT,
water depths.
a marine-growth-resistant local-position
ELECTRIC CHOKE ACTUATOR
indicator and an ROV override.
The CameronDC™ electric choke
AQUATORQ™
actua-
ACTUATOR
SLCA Actuator
Digitally Calibrateable LVDT
The
Aqua-Torq Actuator is designed to
Cameron’s WILLIS Control Choke cage-style
trim design incorporates “hydrodynamic energy
dissipation” to reduce erosion problems while
ensuring positive flow.
®
provide precise incremental steps from
tor is integrated with the best available
open to closed. Oil-filled and pressure-
choke technology for optimum reliabil-
compensated, it incorporates a marine-
ity, increased availability and improved
growth-resistant local-position indicator
operability.
and is available with an internal LVDT.
The actuator is fitted with flushing ports,
6
F L O W C ON T R O L
Combine this with an all-electric tree
system or as a stand-alone DC electric
choke operating off a traditional electrohydraulic control system with its own
power and controls, and quickly gain
the advantage with longer stepouts,
rapid choke operation and zero emission
to the environment.
Control choke trim
minimizes erosion,
maximizes control
C
Cameron Provides a Wide Variety
of Control Choke Trims
ameron’s subsea chokes are available in plug and cage (forward
and reverse flow), external sleeve and
anti-cavitation multi-stage trims.
In these cage-style trim designs, the
production fluid is directed through
the cage port so that it impinges
upon itself. The energy of the fluid is
dissipated within the tungsten carbide
trim, reducing the wear on the choke
and downstream components.
Design features
Cameron’s Stand-Alone
DC Electric Choke
• Availability of both plug and cage
flow or impact from entrained solids
and external sleeve trims provides
• Trim ports and geometry design
interchangeability, maximum
reduces wear and noise, maximizes
Cameron’s actuator performance
flexibility and lower costs over the
flow and controls pressure throughout
• Meets API 6A/ISO 10423-PR2 and
life of the field
the choke’s operating range
API 17D/ ISO 13628-4 for temperature
• Thick cross-sections of tungsten
• Pressure-balanced stem and thrust
ranges from 0° F to 150° F (-18° C to 66° C)
carbide material provide extensive
bearings reduce torque, allowing
• Hyperbaric tested to 11,400-foot
erosion resistance and reduced wear
minimized stem loads and
(3475-meter) water depths and
• Robust metal outer cage protects
actuation requirements
million-pulse endurance tested
internal components from slugged
Premier Manufacturing
Cameron’s choke manufacturing facility in Longford, Ireland, has global responsibil-
ity for the design and manufacturing of all subsea chokes and intervention tooling, as
well as subsea chemical-injection metering valves (CIMV) and gate valve actuators.
This plant is equipped with sophisticated tools and flow control technology, including
CNC machining centers; fabrication and weld-cladding stations; hydrotest bays; TV-
monitored hydrostatic and gas test facilities rated to 30,000 psi; advanced NDE capabilities such as X-ray, UT and PMI; and a semi-automated blast-and-paint facility.
Cameron’s in-house R&D group works hand in hand with sales and manufacturing
teams in 21 countries worldwide, with further support provided by 65 strategically
located CAMSERV™ aftermarket centers. Wherever you need us, we’re already there.
Longford, Ireland
7
PLUG AND CAGE TRIM
Choke Sizing Program
Cameron’s plug and cage trim uses
a plug that throttles the flow on the
Because choosing the right trim
size is vital to your success in the
field, Cameron has developed a comprehensive choke sizing program.
inside diameter of the ported cage.
The tungsten carbide plug assembly
in conjunction with the cage provides
optimum wear resistance in erosive
conditions. In addition, an outer cage
provides protection from impact dam-
Based on the flow and pressure
requirements of the application,
age during well cleanup or from failed
downhole completions.
the software analyzes and specifies
the optimum choke size and trim
configuration for an array of
flow conditions.
Cameron’s choke sizing program
External Sleeve Trim
was developed according to ANSI/
reverse-angle flow sleeve extends the
ISA S75.01/02 (IEC 60534-2-1 Mod)
life of the trim by reducing annular
requirements in a specially designed
flow-by.
CV test flow loop.
Plug and Cage Trim
Choke Sizing Flow Loop
Field applications have shown this trim
to be the industry leader in erosion
The cage construction enables tungsten
performance. In two separate joint
carbide components to withstand the
industry projects, Cameron’s external
tensile forces generated during reverse
sleeve chokes were rated the most
flow. This allows the trim to be used
wear-resistant to sand-laden gas or
during production (forward flow) and
liquified production service. As a result,
injection (reverse flow) applications.
this trim is the preferred solution for
severe sand service.
This versatile trim offers excellent erosion
resistance and precise control, making
it ideally suited to deepwater oil or gas
production. Because of its high capacity,
the plug and cage trim design is perfect
for flow optimization near the end of
Cameron’s Choke Sizing Program
the life of a well.
EXTERNAL SLEEVE TRIM
This design incorporates an outer
sleeve that throttles the flow on the
outside diameter of the ported cage.
A tungsten carbide flow sleeve and
seat provide optimum wear resistance
in erosive conditions. In addition, a
8
Reverse Flow-in Plug and Cage
F L O W C ON T R O L
WATER INJECTION
through a valve, the pressure drops from
(ANTI-CAVITATION) TRIM
the inlet pressure (P1 ) to a minimum
Cameron offers two- and three-stage
pressure (Pvc ) in the vena contracta just
DBA and multi-stage (MS) trims for water
injection service. These custom engineered
anti-cavitation trims can be interchanged
past the restriction. If the Pvc falls below
the liquid’s vapor pressure (Pv), vaporization
occurs and vapor bubbles form. As the
with production trims as required.
liquid moves downstream from the vena
The Cavitation Problem
If this outlet pressure, P2 , is above
Cavitation is a serious enemy to efficient
the vapor pressure, the vapor bubbles
flow control. Cavitation’s destructive
collapse. This causes high pressure shock
effects include high noise levels, vibration
waves, which can cause damage to
and damage to valve and trim materials.
nearby metal surfaces.
contracta, the pressure recovers to P2 .
Cavitation is the formation and sudden
collapse of vapor bubbles in a flowing
liquid. During the liquid’s passage
The Cameron Solution
Cameron’s DBA and MS trims were
developed specifically to combat cavitation in water injection applications. Their
multiple pressure drop design divides
the normally large pressure drop into a
series of smaller pressure drops. Cavitation
is eliminated by keeping the pressure at
the vena contracta, Pvc , above the vapor
pressure, Pv , of the liquid. The result is a
trim that eliminates the threat of cavitation, reduces noise and vibration in
downstream pipes and joints, improves
control and performance, and increases
MS Three-Stage Anti-Cavitation Trim
DBA Two-Stage Anti-Cavitation Trim
production life.
Multi-Stage Anti-Cavitation Trims
DBA Flow Characteristics
Pressure Drop Profile Through One Stage
Minimum pressure (Pvc ) stays above vapor pressure
P1 Inlet Pressure
P2 Outlet Pressure
Pressure
Pressure
P1 Inlet Pressure
Vapor Pressure
P2 Outlet Pressure
Vapor Formation
Single-Stage Pressure Letdown
PVC
Cavitation
Begins
Vapor Pressure
PVC
PVC
PVC
Three-Stage Multi-Stage Pressure Letdown
9
FLOW CONTROL
Cameron Ireland Ltd.
Aghafad, Longford
Republic of Ireland
Tel
353.43.3350600
Fax 353.43.3341560
11331 Tanner Road
Houston, Texas 77041-6901
USA
Tel
713.280.3000
Fax 713.280.3056
www.c-a-m.com
HSE Policy Statement
At Cameron, we are committed ethically, financially and personally to a working environment
where no one gets hurt, nothing gets harmed.
© 2009 Cameron | Aqua-Torq, CAMSERV, MOV, CameronDC, SpoolTree, WILLIS and CAMTROL are registered trademarks of Cameron. | Printed in USA | Simon Printing | Q5000 | 07/09 | TC9702
Front cover shows the installation of a manifold containing Compact Chokes on the Puffin field in the Timor Sea about 700 km west of Darwin, Australia.