1. Introduction to Well Completions
Agenda
At the end of this presentation, you will be able to:
Define completion
Factors influencing completion design.
List and define the different types of completion
Describe surface control equipments
Define subsea completion
M 4: Completion
D 01: Module Objectives
Audio Narration:
In this module, you will learn about the steps in the process of completion in oil drilling, the equipments used, and about surface control equipments.
At the end of this module, you will be able to:
Define completion
Describe the process of completion
List and define the different types of completion
Describe surface control equipments
Define subsea completion
Note to GD:
Bullets in sync with VO.
RECREATE Image: show diagram of an oil well

2. Completion Completion Process
30’’ CASING
20’’ CASING
13 3/8’’ CASING
7’’ LINER
RESERVOIR
SEA BED
PLATFORM
Production casing (9 5/8)
Downhole Equipment
Safety Equipment
After exploratory drilling confirms the presence of an oil or natural gas reservoir, the hydrocarbons are brought to the surface.
Once the design well depth is reached, the formation is tested and evaluated to determine whether the well is to be completed for production, or plugged and abandoned.
This decision is taken based on the information available on reservoir characteristics.
To complete the well production, casing is installed and cemented, and the drilling rig is dismantled and moved to the next site.
A service rig is brought in to perforate the production casing and run production tubing along with down hole equipments.
The installation of surface safety equipments takes place and production begins.
M 4: Completion
T 01: Completion Process
D 01: Introduction
Audio Narration:
After drilling has confirmed the presence of an oil or natural gas reservoir, the hydrocarbons are brought to the surface.
Once the design well depth is reached, the formation must be tested and evaluated to determine whether the well will be completed for production, or plugged and abandoned.
This decision is taken on the information available on reservoir characteristics, such as the size of the reservoir, the porosity and permeability of the reservoir rock, and the amount of natural energy or reservoir pressure, within the reservoir.
To complete the well production, casing is installed and cemented and the drilling rig is dismantled and moved to the next site.
A service rig is brought in to perforate the production casing and run production tubing along with downhole equipments.
If no further pre-production servicing is needed, the surface safety equipments, such as the Christmas tree are installed, and production begins.
Completion Process

3. Completion What is Completion? Completion Process
It’s a link between drilling the borehole and
the production phase.
Well completion creates a dependable pathway
to the surface for the hydrocarbons.
Once the well is drilled, it has to be made ready
for the safe and efficient production of oil.
The term ‘completion’ describes the assembly of
Down hole tubulars and other safety equipments
that is required to enable the safe and efficient
production of oil or gas from the well after it has
been drilled.
M 4: Completion
Topic 1: Completion
D 02: What is Completion?
Audio Narration:
Once a natural gas or oil well is drilled, and it has been verified that commercially viable quantities of natural gas are present for extraction, the well must be 'completed' to allow for the flow of petroleum or natural gas out of the formation and up to the surface. Well completion creates a dependable pathway to the surface for the hydrocarbons.
Once the well is drilled, it has to be made ready for the safe and efficient production of oil.
Completion refers to the assembly of downhole tubulars and other safety equipments that is required to enable the safe and efficient production of oil or gas from the well after it has been drilled.
Note to GD:
Show the oil well. Let the labels appear one after another.
Completion Process

4. FACTORS INFLUENCING COMPLETIONS DESIGN.
Purpose of the well
The environment
Drilling
The reservoir
Production
Completion techniques

5. Purpose of the well
Exploration wells: To obtain preliminary data on a reservoir, nature and characteristics of the fluids on the reservoir, pay zone characteristics (pressure, temperature, permeability and productivity)
Appraisal or confirmation: Refine or complete the data from exploration and determine the off-wellbore characteristics (permeability, reservoir boundaries, existence of faults/discontinuity)
Developmental well: This stage brings the wells on the production stream. Assess well conditions and effectiveness of completions and obtain further info on the well.
Production- productivity
Injection- Optimize reservoir pressure
Observation-monitor variations in reservoir parameters

6. Parameters related to the Environment
Constrains related to country/site/location of well i.e land or offshore.
Environmental restrictions involve:
Difficulty in obtaining supplies
Available space
Available utilities
Safety rules and regulations
Certain operations that may or may not be possible
Meteorological and oceanographic conditions must also be taken into consideration where applicable.

7. Parameters related to the Drilling
Types of rigs (drilling/completions)
Well profile- horizontal/directional
Drilling and casing program
Drilling in the pay zone(s) and drilling fluids- formation damage and fluid contamination.
Cementing the production casing
Drilling and casing program- have a borehole big enough to accommodate the equipment that will be installed in it.
In contrast, if the diameter of the pay zone is is increased beyond what is required by the production equipment, it does not boost the well flow capacity very much.
The inside diameter is effectively usable in the well once all the drilling and casing phases have been concluded.

8. Parameters related to the Reservoir
Reservoir pressure and its changes- need for injection wells?
Interface between fluids and their changes- water encroachment
Number of levels to be produced
Rock characteristics and fluid types
Production profile and the number of wells required.

9. Parameters related to the Production
Safety- compliance with various regulations
Flowing well or artificial lift- a wells flow capability depends on natural changes in bottom hole pressure versus cumulative production.
Operating conditions- space availability, operating fluids-erosion/corrosion
Anticipated measurement, maintenance or work over operations- maintenance and repair operations to ensure the well reaches its lifetime

10. Other factors
Parameters related to completion techniques: general configuration, pay zone to bore hole connection, treatment of the formation, equipment installed, artificial lift
Synthesis-How completion is designed- completions should be designed to optimize productivity/injectivity performance, make sure the well produces reliably and safely, optimize the implemantation of atrificial lift, optimize equipment lifetime and make it easy o change all or some of the equipment in the future without much difficulty.