1. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
FMC Technologies' Intervention Workover Control Systems (IWOCS) are designed to control the rig-based
and vessel-based Well Access Systems (WAS) tools and operations. IWOCS provide the operator with the
ability to perform secure and effective installation, completion and intervention tasks offshore, and can
be supplied fully compliant and certified to Safety Integrity Level 2 (SIL-2). The IWOCS can also be used
separate from the WAS in controlling the subsea tree under Tree on Wire operations or well start-up, or
to control subsea trees and equipment during non-FMCTI operations.
Intervention Workover
Control Systems
2. www.fmctechnologies.com/SubseaSystems
Control System
Tree, EDP/LRP and LS Control System
TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
FMC Technologies' Intervention Workover Control Systems (IWOCS) enable efficient intervention and
completion work on wells through existing subsea completion systems.
Applications, Functions
and Components
IWOCS operate in and change between the
following operations:
»» Installation and completion of subsea wells
»» Heavy intervention
»» Coiled tubing intervention
»» Wireline intervention and other light well
intervention tasks
»» Through Tubing Rotary Drilling
»» Tree on Wire
»» Riserless light well intervention
»» Open water Umbilical on Wire operations
IWOCS carry out the following main functions:
»» Normal operation of tree functions and monitoring
of production equipment and system status
»» Normal operation of well access functions and
monitoring of equipment status
»» Execution of:
- Production Shutdown (PSD)
- Emergency Shutdown (ESD)
- Emergency Quick Disconnect (EQD)
IWOCS main component options:
»» Container split solutions:
- Hydraulic Power Unit (HPU)
- Hydraulic Distribution Unit (HDU)
- Master Control Panel (MCP)
»» Subsea tree umbilical and reel system
»» Simplified Landing String (SLS)/Landing String (LS)
umbilical and reel system
»» High Set Lubricator Valve (HSLV) umbilical
and reel system
»» Service umbilical and reel system
»» Annulus hose
»» Work Over Control Module for Emergency
Disconnect Package (EDP)
»» Subsea jumper systems for EDP, SLS/LS and
tree running tool
»» Riser monitoring and management
»» Launch and Retrieval System (LARS)
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3. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
System Description
Typical modular system configurations:
Subsea Tree Control System:
»» Communicates with Subsea Control Module (SCM)
mounted during installation and other intervention jobs
Installation Control System:
»» Control of SCM and third-party Well Access System
(WAS) under installation jobs
Subsea Tree and Landing String
(LS) Control System:
»» Control of SCM and LS under installation
and intervention
Subsea Tree and EDP/LRP Control System:
»» Control of SCM and Workover Control Module (WOCM)
for EDP/LRP under installation and intervention
Subsea Tree and EDP/LRP and LS Control System:
»» Control of SCM, WOCM for EDP/LRP and LS
under installation and intervention
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4. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
Intervention Workover Control Systems Overview
Intervention Workover Control Systems Overview
Subsea Control Module
Installation Control System
Tree and LS Control System
Tr
Installation Control System
Subsea Control Module
Tree and LS Control System
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5. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
www.fmctechnologies.com/SubseaSystems
Tree and EDP/LRP Control System
Tree, EDP/LRP and LS Control System
Tree and EDP/LRP Control System
Tree, EDP/LRP and
LS Control System
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6. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
HPU/HDU/MCP
Functions:
»» IWOCS is designed so that no single failure
will cause an unintended system shut-down;
unacceptable risk for personnel or environmental
safety; or loss of financial assets
»» HPU/HDU/MCP can be one or several containers,
which are typically 12-35ft. They are DNV 2.7-
1 certified and A60 fire-rated containers, with
control room and hydraulic sections
»» Shutdown and PSD/ESD/EQD panels are included
in system
»» Remote control panel for installation in driller
cabin will show the same information as HMI
in MCP control room
»» Redundant communication, A and B side with
WOCM on EDP and SCM on tree is typically signal-
on power
»» SIL-2 rated safety system, upon request
»» Capabilities for third-party access and connectivity
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7. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
IWOCS UCOS Computer System
The IWOCS User Configurable Open System (UCOS) Master Control Station (MCS) delivers a field-proven,
globally standardized computer system with common and recognizable user interfaces worldwide.
The UCOS MCS can provide the following functionality:
»» Well monitoring and control
»» Intelligent well control
»» Robust choke control
»» Dynamic DHI control
»» Dynamic CANBUS network control
»» Flow calculation
»» Sand rate calculation
»» MCS redundancy monitoring and control
»» Subsea communication summary
»» Well shutdown control
»» EPU monitoring and control
»» HPU monitoring and control
»» Third-party monitoring and control
»» Trending
»» Alarm summary
»» Event history
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8. TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
Umbilicals and Reels
Functions:
»» In-riser Landing String (electro hydraulic
communications) and Lubricator Valve
(hydraulic communications) umbilicals are
optimized for size to minimize risk of damage
»» Open water umbilicals (electro hydraulic
and optic communications) are designs that
maximize flexibility towards FMC Technologies'
and other suppliers’ subsea tree production
control systems
»» Umbilical reels can be delivered as electrical
or pneumatic driven with a local and remote
control panel
»» Can all run manually or have a
constant tension
Hydraulic Flying Leads
(HFLs)
»» Provides hydraulic communication from
umbilical to subsea equipment
»» Up to 15,000psi
»» Terminated using standard hotstabs, MQC
plates and coupler configurations
»» Emergency disconnect configurations
available for EDP/LRP and BOP
Electrical Flying Leads (EFLs)
»» Provides electrical communication from
umbilical to subsea equipment
»» ROV installation and handling
»» Emergency disconnect configurations available
for EDP/LRP and BOP needs
»» Maximum water depth 10,000 ft. (3,048m)
»» The silicone, oil-filled hose functions as the first
barrier against sea water ingress, and the wire
insulation together with the termination boot
seals function as a second barrier
»» Hoses have no metal parts to corrode
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9. Launch and Recovery
System (LARS)
»» LARS includes:
• Wireline winch
• Passive Heave Compensator
• Hydraulic Power Unit (HPU)
• Remote control panel
• A-Frame
»» Deploys and retrieves the Umbilical
Termination Assembly (UTA)
»» Deployment performed off critical path
»» Saves Moon Pool space, or deployment
on smaller vessels
Umbilical Termination
Assembly (UTA)
»» Terminates the umbilical subsea
»» Ability to compensate for heave
»» Emergency disconnect functionality
»» Provides jumpers for:
• EFL – configurable per project
• HFL – configurable per project
• ROV – hotstab flying lead
TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
LARS A-Frame
LARS Winch
LARS Passive Heave
Compensator
LARS Remote
Control Panel
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10. Subsea Tree and EDP/LRP
Control Pod
The Workover Control Module (WOCM) will be installed on
the EDP and used for the following functions:
»» Operation of valves and connectors on the EDP and LRP
»» Operation of the Direct Hydraulic Operated tree valves
»» Operation of connectors on the choke module
»» Monitoring of the PT/TT in the main bore on the LRP
»» Monitoring of the PT/TT in the annulus bore on the LRP
»» Close the defined barrier envelopes required for ESD
and EQD
»» Includes redundant electronic modules and a manifold
block for solenoid valves
»» PSD600 cards are included for projects with SIL
requirements
Tubing Hanger (TH) and Landing
String (LS) Control Pod
The Riser Control Module (RCM) and the Landing String
Accumulator Module (LAM) will sit within the vessel
marine riser system and be used for the following
functions:
»» Operation of valves and connectors on the LS and
Tubing Hanger Running Tool (THRT)
»» Operation of the Tubing Hanger Latch and pressure test
functions
»» Closure of the defined barrier envelopes required for
ESD and EQD
»» Operation of TH soft land piston and integral valves
where applicable
»» Operation of the downhole completion valves in the
main bore of the completion below the TH
»» Monitoring of the downhole PT/TT in the main bore of
the completion below the TH
»» Includes redundant solenoid valves and valve position
verification for projects with SIL requirements
TECHNICAL DESCRIPTION INTERVENTION WORKOVER CONTROL SYSTEMS
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