This document provides an overview of offshore oil and gas production systems. It describes the major components which include wells, platforms, pipelines and processing facilities. It outlines different types of offshore platforms suited for varying water depths, such as fixed steel structures, compliant towers, jack-up platforms and floating production systems. It discusses the crews and roles required to operate offshore platforms. It also summarizes fire and explosion protection systems, environmental protection measures, and how supervisory control and data acquisition (SCADA) systems are used to remotely monitor wells.

1. Offshore Oil and Gas
Production System
Nguyễn Quang Minh
Mechanical Engineer
Vietnam Oil and Gas Group
PetroVietnam Gas Joint Stock Corporation

2. Content
I. Overview
II. Offshore Platform
III. Crews
IV. SCADA
V. Fire & Explosion Protection
VI. Environment Protection
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3. WELL
PLATFORMS
PROCESS
PLATFORMS
ONSHORE
TERMINALS
DATA/SCADA
POWER
FLUID ( OIL/GAS/WATER )
INJECTION WATER
LIFT GAS
FSO
OIL TO REFINERY
GAS TO CONSUMERS
OIL
GAS
WELL
WELL FLUID
INJ WATER
LIFT GAS
UMBILICAL
(DATA/WELL CONTROL
WELLS/CONNECTED WELL PLATFORM
SEPARATION MODULE‐ OIL/GAS/WATER
GAS COMPRESSION AND DEHYDRATION MODULE
SEA WATER TREATMENT FOR WATER INJECTION
PRODUCED WATER TREATEMENT MODULE
POWER GENERATION
UTILITIES ‐ WATER/SUPPLIES
LIVING QUARTERS
DRILLING/WELL SERVICING RIG MODULE
WELLS
WELL TESTING
PRODN OPTIMIZATION
WELL CONTROL
WELL SERVICING
TELEMETRY / SCADA
WELLS
OIL PRODUCERS
GAS PRODUCERS
INJECTION WELLS
I. OVERVIEW
OFFSHORE PRODUCTION SYSTEM‐ A SCHEMATIC
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5. THE MAJOR ELEMENTS OF OFFSHORE
PRODUCTION SYSTEM
• WELLS (SUBSEA/PLATFORM WELLS)
• WELL PLATFORMS/WELL SERVICING RIGS
• FEEDER SUBSEA PIPELINES
• PROCESSING PLATFORMS
• EXPORT PIPELINES FOR OIL/GAS
• TANKERS FOR EVACUATION OF OIL
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6. II. OFFSHORE PLATFORMS
- A large structure used to house workers and machinery needed to
drill and/or extract oil and natural gas through wells in the ocean bed
- Though as technology improves, drilling and production in deeper
waters becomes both feasible and profitable.
- Many platforms also have remote wellheads attached by umbilical
connections, these may be single wells or a manifold centre for
multiple wells
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7. A. Type of offshore platforms
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8. • Fixed Steel Structure: Giàn cố định
• Compliant Tower: Tháp mềm
• Jack-up Platform: Giàn tự nâng
• Concrete Gravity Base Structure: Giàn trọng lực
• Tension Leg Platform (TLP): Giàn chân căng
• Semi-submersible Vessel: Giàn nửa chìm nửa nổi
• Floating Production System: Hệ thống khai thác nổi
• Spar Platform: Giàn Spar
• Subsea system
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9. 1. Fixed Steel Structure
- The traditional offshore structure
consists of weld steel, tubular
framework or jacket to support
the topside facilities. Piles driven
into the seafloor secure the jacket.
- The Fixed Steel Structures are
restricted to shallow water
developments with water deep
about 1500 ft.
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10. 2. Compliant Tower
- They have a steel tubular jacket that is used to
support the topside facilities and they are
secured to the seafloor with piles.
- Unlike fixed platforms, compliant towers yield
to the water and wind movements in a manner
similar to floating structures. The jacket of a
compliant tower has smaller dimensions than
those of a fixed platform.
- Compliant towers are designed to sustain
significant lateral deflections and forces, and are
typically used in water depths ranging from
1,500 to 3,000 ft
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11. 3. Jack-up Platform
- The Jack-up Platform consists of
a triangular shaped (sometimes
rectangular), box section barge
fitted with three (sometimes
four) moveable legs which
enable the vessel to stand to
the seabed in water depths of
up to 120 m (400 ft).
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12. 4. Concrete Gravity Base Structure
- The Concrete Gravity Base Structure have
been constructed using a base
manufactured from reinforced concrete.
- The design of base includes void spaces or
caissons to provided the structure with a
natural buoyancy which will enable it to
be floated to field development location.
Once on location the void spaces are
flooded on the seabed whilst the topside
modules are lifted into place.
- The void spaces then used as storage
compartments for crude oil, or filled with
permanent iron ore ballast.
- The colossal weight of concrete structures
obviates the need to install foundation
piles, hence the name gravity base
structure.
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13. 5. Tension Leg Platform (TLP)
- A Tension Leg Platform (TLP) is a buoyant
platform held in place by a mooring
system.
- The mooring system is a set of tension
legs or tendons attached to the platform
and connected to a template or
foundation on the seafloor. The template
is held in place by piles driven into the
seafloor. This method dampens the
vertical motions of the platform, but
allows for horizontal movements.
- TLPs are used in water depths from 1500
ft to 7000 ft.
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14. 6. Semi-submersible Vessel
- Have twin hulls (columns and
pontoons) of sufficient buoyancy
to cause the structure to float
- It can be moved from place to
place; can be ballasted up or down
by altering the amount of flooding
in buoyancy tanks; they are
generally anchored by
combinations of chain during
drilling and/or production
operations, though they can also
be kept in place by the use of
dynamic positioning.
- Semi-submersibles can be used in
water depths from 200 to 10,000
feet.
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15. 7. FPSO
- FPSOs are large ships
equipped with processing
facilities and moored to a
location for a long period.
- The main types of floating
production systems are:
• FPSO (floating production,
storage, and offloading
system)
• FSO (floating storage and
offloading system)
• FSU (floating storage unit).
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17. 8. SPAR Platform
• A spar is a type of floating oil
platform typically used in very deep
waters, and is named for logs used as
buoys in shipping that are moored in
place vertically.
• A spar platform consists of a large
diameter, single vertica cylinder
supporting a deck. The cylinder is
weighted at the bottom by a chamber
filled with a material that is denser
than water to lower the center of
gravity of the platform and provide
stability. Spars are anchored to the
seabed by way of a spread mooring
system with either a chain-wire-chain
• 10 000 ft
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18. 9. Subsea system
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19. B. Facilities of Offshore Platform
- Wellhead Platform
- Process Platform
- Platform Complex
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20. 1. Wellhead Platform (WHP)
- A wellhead platform includes an integrated deck, utility systems,
wellhead systems, living quarters, a helideck and drilling facilities.
- WHPs are normally unmanned. They are designed to be operated
remotely and visited during routine inspection and maintenance
activities.
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21. 2. Process Platform
- Separation (Oil, Gas and
Produced water)
- Gas Compression & dehydration
- Produced Water Conditioning
- Sea water processing &
injection system
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22. 3. Platform Complex
Ekofish Complex
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23. III. Crews
• OIM (offshore installation manager) is the ultimate authority during his/her shift and makes
the essential decisions regarding the operation of the platform.
• Operations Team Leader (OTL)
• Offshore Operations Engineer (OOE) is the senior technical authority on the platform
• PSTL or Operations coordinator for managing crew changes
• Dynamic Positioning Operator, navigation, ship or vessel maneuvering (MODU), station
keeping, fire and gas systems operations in the event of incident
• 2nd Mate ‐Meets manning requirements of flag state, operates Fast Rescue craft, cargo ops,
fire team leader.
• Ballast Control Operator also fire and gas systems operator
• Crane operators to operate the cranes for lifting cargo around the platform and between
boats.
• Scaffolders to rig up scaffolding for when it is required for workers to work at height.
• Coxwains for maintaining the lifeboats and manning them if necessary.
• Control room operators ‐Especially FPSO or Production platforms.
• Catering crew will include people tasked with performing essential functions such as
cooking, laundry and cleaning the accommodation.
• Production techs for running the production plant
• Helicopter Pilot(s) live on some platforms that have a helicopter based offshore. The
helicopter flight crew transports workers to other platforms or to shore on crew changes.
• Maintenance technicians (instrument ,electrical ,mechanical )
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24. IV. SCADA
- SUPERVISORY CONTROL AND DATA
ACQUISITION
- Gather necessary DATA from a
REMOTELY LOCATED Oil/Gas well
and Well Platform with the help of
Field Transmitters & RTU and send
it to the DATA GATHERING &
ANALYSIS point.
Sensor at
well platform
RTUs, PLCs
Computer
Actuator at
well platform
SCADA schematic
Pressure
Temp
Lever…
Valve
Pump…
CPU
Monitor
Server
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25. SCADA Management
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26. Benefit of SCADA
• 24 hrs online monitoring control from onshore center
• Historical Data and trending helps in Troubleshooting
• Ability to close wells remotely during emergency.
• Better Production optimization of individual wells
• Instant alerts in case of Well closures, ESD, FSD and control panel
failure
• Optimum utilization of Manpower for attending to well problems
• Reduction in number of physical visits to well platforms resulting in
optimization of Helicopter sorties.
• To observe slugging in pipelines.
• Lift gas allocation for each well
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27. V. FIRE AND EXPLOSION PROTECTION
- Unpredictable
- Cause: Human and Natural
Disater

- Fire & Explosion Protection
- Risk Management
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28. - Emergency Shutdown (ESD) system
+ Levels of Shutdown
+ Isolation Valve Requirements
- Depressurization, Blowdown and Venting
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29. Fire Detection & Suppression System
Detection system
- Gas Detection
- Fusible Plug
- Fire Detection
- Smoke Detection
- Heat Detection
Suppression system
- Fire water pump
- Water Sprinkler
- Dry Chemical
- CO2 Extinguisher
- AFFF SYSTEM
Escape / Abandon
- Scape Ladder
- Scramble Net
- Life Ring
- Life Raft
- Life Boat
- Jumping Rope
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30. VI. Environment Protection
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Contact: minha4k47@yahoo.com.vn