well completion fundamentals Theory and process-.pdf

The Fundamentals of oil well completions.

1. Slide #1Well Completions FundamentalsOgbon

2. Slide #2Well Completions FundamentalsOgbon
Introduction
Bottom Hole Completion Techniques
Perforation
Upper Hole Completion
Production String & Christmas Tree
Packers
Tubular Configuration in Completion
Horizontal Completions
Christmas Tree
Course Content

3. Slide #3Well Completions FundamentalsOgbon
Introduction to Well Completions Fundamentals

4. Slide #4Well Completions FundamentalsOgbon
After thorough analysis of formation evaluation data, a decision is reached either to
complete the well or abandon it.
Well will be abandoned by plugging it in if its production is not of commercial
value. An abandoned well can be reopened in the future if oil prices justify its
commercial viability.
When well production is commercially viable, it is completed for production.
Introduction to Well Completion

5. Slide #5Well Completions FundamentalsOgbon
Introduction to Well Completion
Well Completion
Well Completion Process is the design, selection and installation
of equipment/devices and the specification of treatment and
procedures necessary to bring the well into production to
satisfy the objectives of the overall field development
Well Completion must allow a safe and controlled flow of
petroleum from the well
It involves joint effort with other sub-disciplines such as production
engineering and reservoir engineering

6. Slide #6Well Completions FundamentalsOgbon
Introduction to Well Completion
Major Processes of Well Completion
Setting of production casing (if required)
Displace drilling fluid with completion fluid
Perforation of Production Casing
Installation of production tubing and set with
packer to Isolate pay zone
Swabbing (if necessary)
Installation of Christmas Tree
Christmas Tree

7. Slide #7Well Completions FundamentalsOgbon
Introduction to Well Completion
Summary of Completion Process

8. Slide #8Well Completions FundamentalsOgbon
Introduction to Well Completion
Key Objectives
Provision of Optimum Well Production or Injection Performance
Safety Across Entire Completion Spectrum
Maximization of the Integrity and Reliability of the Completion
Minimum Operational Cost for Initial Completion and Workover Per Unit
Volume of Produced or Injected Fluid

9. Slide #9Well Completions FundamentalsOgbon
Factors For Consideration in Completion Process Design
Fluids to Fill Wellbore During Completion
Formation Fluid Wellbore Entry Specification
Open Hole
Perforated Completion
Bottom Hole Completion Technique Specifications
Completion String Design
Production Conduit(Tubing) Selection
Potential of oil production and the planning of tertiary recovery, i.e. do we need
any artificial lift in the future?
Introduction to Well Completion

10. Slide #10Well Completions FundamentalsOgbon
Types of Flow
Casing Flow:
Large flowrate.
No tubing is required.
Used mostly in Saudi Arabia and other Middle East countries.
Tubing and Annulus Flow:
Large flowrate.
When flow segregation is needed.
Tubing Flow:
Offers more safety.
Uses one tubing string or more.
Introduction to Well Completion

11. Slide #11Well Completions FundamentalsOgbon
Bottom Hole Completion Techniques

12. Slide #12Well Completions FundamentalsOgbon
Bottom-Hole Completion Techniques
Bottom Hole Completion Techniques
The bottom-hole completion technique specifies
how the reservoir fluid should enter the wellbore
Types of Bottom-Hole completion Techniques
OPEN HOLE(Barefoot Completion)
For Very Hard and Competent Formation
Production Casing Cemented on Top of Pay Zone
Wellbore Left Bare
Has Higher Inflow Performance
Commonly Used in Multilateral Wells
Not Adaptable for Selective Control of Fluid
Production

13. Slide #13Well Completions FundamentalsOgbon
WELL COMPLETION TECHNIQUES
Types of Bottom Hole Completion Techniques
Liner Completions
Screen or Pre-Slotted Liner Completion
Production Casing Cemented on Top of Pay Zone
A Screen or Pre-slotted Pipe is Hanged from
Production Casing and Set Over Pay Zone
Screen Provides Stability for Unconsolidated
Formations
Mostly Applicable in Horizontal well Completions
through Unconsolidated Zones

14. Slide #14Well Completions FundamentalsOgbon
WELL COMPLETION TECHNIQUES
Types of Bottom Hole Completion Techniques
Liner Completions
Perforated Liner Completion
Cemented Liner is then Perforated

15. Slide #15Well Completions FundamentalsOgbon
WELL COMPLETION TECHNIQUES
Bottom Hole Completion Techniques
Perforated Completion
Production Casing Set and
Cemented Over Pay Zone and
Perforated

16. Slide #16Well Completions FundamentalsOgbon
WELL COMPLETION TECHNIQUES
Bottom Hole Completion Techniques
Perforated Tubinglessor Reduced
Diameter Completion
Production tubing is cemented and
perforated for production.

17. Slide #17Well Completions FundamentalsOgbon
Perforations

18. Slide #18Well Completions FundamentalsOgbon
PERFORATION
Definition
Piercing of Wellbore Walls Into Formation to Allow Formation Fluid Flow into
Wellbore
Perforation Objectives
Provision of an Undamaged and Clean Access Between the Wellbore and
Formation
Ensuring the Shooting OR Piercing of Smooth and Round Holes in the
Casing and Cement
Enabling Maximum Flow Rate With Minimum Number of Perforations
Causing Minimum Damage to Casing and Cement
Penetration of Pay Zone as Far as Possible

19. Slide #19Well Completions FundamentalsOgbon
PERFORATION
Perforation Fluids
This is the fluid that placed against the producing formation during
perforation.
Ideally, fluid should have no solids.
Types of Perforation Fluids
Salt water:
Clean water poses no problem. When overbalanced, may push charge
debris into formation.
Acetic acid:
Excellent perforating fluid under most conditions. The presence of H
2S
may magnify corrosion problems.
Nitrogen:
Useful in low pressure formations, or when associated with high rig time
or swabbing costs, or when a special test requires formation to be free
from contamination.

20. Slide #20Well Completions FundamentalsOgbon
PERFORATION
Perforation Methods
Bullet Perforation
Carried Out by Multi-Barrel Gun Run
into Hole on Wireline
Detonated on Surface
Bullets Leave Clean Hole and Cause
Little Damage to Casing and Cement
Multi-Barrel Gun
Detonator
Gun Barrel
in Well

21. Slide #21Well Completions FundamentalsOgbon
Perforation
Bullet Perforation
Technique

22. Slide #22Well Completions FundamentalsOgbon
Perforation
Jet Perforation Process
Piercing Done By Shaped-Charged
Explosives
Perforation Achieved With a Jet of
High-Pressure and High Velocity Gas
Job Completed

23. Slide #23Well Completions FundamentalsOgbon
Perforation
Thru-Tubing Perforation
Gun Lowered through Tubing and
Perforation Through Casing and Into
Formation
Guns are By Far Smaller and More Powerful
FORMATION
During Perforation After
Perforation
Charges Going Out Formation Fluid
Flowing in

24. Slide #24Well Completions FundamentalsOgbon
Upper Completions

25. Slide #25Well Completions FundamentalsOgbon
Upper-Hole Completion
This involved the installation of the production tubing, its accessories and
the Christmas Tree
The production tubing is normally fasted to the production casing with a
sealing element device called packer

26. Slide #26Well Completions FundamentalsOgbon
Upper-Hole Completion
Production String
Conduit for Formation Fluid Flow to
Surface
Components
Tubing
Connected to (Suspended on)
the Christmas Tree on the
Surface
Stabilised and Held Stationary
in Casing in the Pay Zone by
Packers
Hydraulic Control Line
Surface
Controlled
Subsurface
Safety Valve -
SCSSV
Tubing
Packer
Tailpipe
Perforations10,000’
<2,000’
9,800’
Approximate
Depths
Xmas Tree

27. Slide #27Well Completions FundamentalsOgbon
Production String
Production Tubing and Major Accessories
Subsurface Safety Valve
Provides Well Emergency Shut Down
Remote Controlled
Direct Controlled
Side Pocket Mandrel
For Gas Lift Mandrels
Sliding Side Door
For Tubing Entry
No go Nipples
Blast Joint (optional)
Circulating Devices, etc

28. Slide #28Well Completions FundamentalsOgbon
Packers
Packers
Tool used to form an annular seal between two concentric
strings of pipe
OR
Tool used to form an annular seal between the pipe and the
wall of the open hole
It is anchored on Top of the Production Zone by its Own
Expansion Against the Internal Wall of Casing
During the Setting Process, The Packing Elements Expand and
form Perfect Seal With the Tubing and the Casing
Isolates the Production Zone
Creates Room for the Formation Fluid to be Forced up into
Tubing.

29. Slide #29Well Completions FundamentalsOgbon
Packers
Packer Fluids
Fluid placed above the topmost packer but never
mud.
Requirements for Packet Fluid
Must be chemically stable.
Acceptable upper limit of corrosivity is 5 mils
per year or if possible, about 1 mil per year.
Packer fluid must have limited settling of solids.
It must provide protection for corrosion or
embrittlement
Packer fluid
Tubing
Reservoir fluid
Production Casing
Reservoir

30. Slide #30Well Completions FundamentalsOgbon
Completion Tubular Configuration
Single Zone Completion Conduit
Single Tubing Run Into Single Producing Zone
Has High Producing Rates
Good for Corrosive Well Fluids
Good for High Pressure Well
Offers Varieties of Hook-up Possibilities
Tubingless Casing Flow
Casing and Tubing Flow
Tubing Flow Without Annular Isolation
Tubing Flow With Annular Isolation
Single Zone

31. Slide #31Well Completions FundamentalsOgbon
Multiple Completion
One well Goes Through Several Pay Zones
Types of Multiple Completions
Single String -Single Packer
Involves Both Tuning and Annular Flow
Tubing Point at Annular Flow Zone Must be
Pressure Protected
Least Expensive Among Multiple Techniques
Casing is Subject to Corrosion and Production
Pressure
Difficulty in Installation of Artificial Lift
Remedial work NOT Possible in Upper Zone
Without Disturbance of Lower Zone
Single String/Packer
Completion Tubular Configuration

32. Slide #32Well Completions FundamentalsOgbon
Single String-Two Packer
A Cross-Over Can allow Upper Layer
to Flow Through Tubing
Has Same Limitation of Single String-
Single Packer
Completion Tubular Configuration

33. Slide #33Well Completions FundamentalsOgbon
Parallel String-Multiple Packer
Allows Gas Lift Installation
Allows Individual Zone
Subsurface Safety Valve
Installation
Allows Wireline Workover
Services
It is Expensive
Completion Tubular Configuration

34. Slide #34Well Completions FundamentalsOgbon
Horizontal Well Completion

35. Slide #35Well Completions FundamentalsOgbon
Multilateral Well Completion
These require specialized pre-frabricated devices
and critical monitoring devices

36. Slide #36Well Completions FundamentalsOgbon
Multilateral Well Completion

37. Slide #37Well Completions FundamentalsOgbon
Christmas Tree
Definition
Production Well Head
Functions
Controls Well Production Fluid Flow
Means for Controlled Formation Fluid to Processing Facilities
Controls Formation Pressure
Controls Production Pressure
Means for Entrance into Well or Formation for Other Production Services

38. Slide #38Well Completions FundamentalsOgbon
Christmas Tree
Components
Casing Hanger (Housing) and Its Accessories
Connects Christmas Tree to Casing
Provides Means for Suspending Tubing
Master Valves
Two -Upper and Lower MV
Always in the Axis of the Tubing
Used to Close the Well in case of Emergency
Wing Valves
Two -with a Choke Body Mounted on Each Flow Branch
A Studded Cross Channels Fluid Through the Wing Valves
Swab Valve
Located on the Axis of Each Tubing
Allows Access to Tubing Internal for Wireline Operation

39. Slide #39Well Completions FundamentalsOgbon
TYPES OF CHRISTMAS TREES
Tubing Connection
Master Valves
Swab Valve
(Wing Valve)
Flow Line
Tubing
Single Completion Christmas Tree

40. Slide #40Well Completions FundamentalsOgbon
Dual Completion Christmas Tree

41. Slide #41Well Completions FundamentalsOgbon