36887825 basics of well completion ep

8/10/2019 36887825 Basics of Well Completion EP

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Oil Exploration & Production

At the end of this presentation, 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

Completion

Agenda


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After exploratory drilling confirms the presence of an oilor natural gas reservoir, the hydrocarbons are brought tothe surface.

Once the design well depth is reached, the formation istested and evaluated to determine whether the well is tobe completed for production, or plugged and abandoned.

This decision is taken based on the information availableon reservoir characteristics.

To complete the well production, casing is installed andcemented, and the drilling rig is dismantled and moved tothe next site.

A service rig is brought in to perforate the productioncasing and run production tubing along with downholeequipments.

The installation of surface safety equipments takes placeand production begins.

30 CASING

20 CASING13 3/8 CASING

7 LINER

RESERVOIR

SEA BED

PLATFORM

Production casing (9 5/8)

Downhole Equipment

Safety Equipment

Introduction

Completion Process

Completion


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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.

Completion Process

What is Completion?

Completion


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Well completion activities include:

Conducting drill stem test

Setting production casing Running production tubing along with downhole

equipments

Installing surface safety equipments

Starting production flow

If it is decided that the well will not be completed,then it will be plugged and abandoned.

Well Completion Activities

Completion Process

Completion


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Setting production casing

Running production tubing along withdownhole equipments




Conducting Drill Stem Test (DST)

To determine the potential of a producing formation, the operator may order a drill stem test

(DST). The DST crew makes up the test tool on the bottom of the drill stem, then lowers it to the

bottom of the hole. Weight is applied to the tool to expand a hard rubber sealer called a packer.

Opening the tool ports allows the formation pressure to be tested. This process enables workers

to determine whether the well can be produced.

Completion Process

Completion


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Setting production casing & perforation

Running production tubing along with downholeequipments




Setting Production Casing

Production casing is the final casing in a well. It can be set from the bottom to the top. Sometimes

a production liner is installed. This casing is set the same as other casings, then cemented in

place.

Completion Process

Completion


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30 CASING

9 5/8 CASING


PRODUCTION TUBING

SEA BED

PLATFORM BOP

RESEVOIR


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30 CASING

9 5/8 CASING


7 LINER

PRODUCTION TUBING

RESEVOIR

SEA BED

PLATFORM

Only this casing

is visible

from outside

Production casing (9 5/8)

WELL HEAD EQUIPMENT

BACK


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Running Production Tubing and Downhole Equipments

A well is usually produced through tubing inserted down the production casing. Oil and gas is

produced more effectively through this smaller-diameter tubing than through the large-diameter

production casing. Joints of tubing are joined together with couplings to make up a tubing string.

Tubing is run into the well similar to casing, but it is smaller in diameter and is removable.

Completion Process

Completion




Running production tubing along with downhole

equipments Installing surface safety equipments




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Installing Surface Safety Equipments

Though the tubings and downhole equipments are present in the well, production cannot

start without installing surface control equipments. They are required to prevent

uncontrolled oil flow out of the well.

Completion Process

Completion









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Starting Production Flow

Production flow is started by washing in the well and setting the packer. The pumping in of wateror brine to flush out the drilling fluid is called washing in. Usually this is enough to start the wellflowing. If this does not work then the flow might be started by pumping high-pressure gas into thewell after setting the packer.

Completion Process

Completion







.



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Downhole Equipment

The parts of a downhole equipment are:

Completion

Gas Lift Valve

Safety Valve

Hydraulic Control Line

Pump Out Plug

Packer

Completion Process


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Well Head

The surface termination of a wellbore that

incorporates facilities for installing casing hangers

during the well construction phase is the well head.

It is a means by which the production tubing is hung,

the Christmas tree and the surface flow-control

facilities are installed, in preparation for the

production phase of the well. The BOP also sits on

top of well head.

The well head is installed on top of the casing before

starting to drill. It has two or three sections. Each

section has two flanges to facilitate the connections

at both the ends.

Surface Control Equipments

Completion

well head

Sections

Flanges


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Each well head section has three

components:

Casing Bowl

Casing Hanger

Tubing Head


Completion

Components of a Well Head


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Each well head section has three

components:

Casing Bowl

Casing Hanger

Tubing Head


Completion


Casing Bowl

The casing bowl consists of heavy fittings that provide aseal between the casing and the surface. It also supports

the entire length of casing that is run all the way down the

well. This piece of equipment typically contains a gripping

mechanism that ensures a tight seal between the head and

the casing itself.

Sealing


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Each well head section has three components:

Casing Bowl

Casing Hanger

Tubing Head


Completion


Casing Hanger

This is the sub-assembly of a well head that supports thecasing string when it is run into the wellbore. The casing

hanger provides a means of ensuring that the string is

correctly located and generally incorporates a sealing

device or system to isolate the casing annulus from upper

well head components.


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Each well head section has three components:

Casing Bowl

Casing HangerTubing Head


Completion


Tubing Head

The tubing head is a well head component that supports

the tubing hanger and provides a means of attaching the

Christmas tree to the well head.


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Tubing Hanger

The tubing hangeris a device attached to

the topmost tubing joint in the well head to

support the tubing string.

The tubing hanger is located in the tubing

head, with both components incorporating

a sealing system to ensure that the tubing

conduit and annulus are hydraulically

isolated.

The tubing hanger assembly supports theweight of the tubing string and seals the

annulus from the upper well head and

Christmas tree components. It also

provides connections at the surface, which

controls the flow of fluids out of the well.


Completion

Anchor bolts to

hold tubing

hanger in place


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1.5 m

20 Casing Terminates Here

Tubing hanger

comes here

Production Casing(9 5/8)

terminates here

A Section

B Section

C Section

30 Casing Remains

Outside

Well Head

Anchor Bolts


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Christmas Tree

The assembly of valves, spools, pressure gauges,

and chokes that are fitted to the well head of the

completed well is called a Christmas Tree. It is used

to control the flow of oil through the tubing hanger.

The function of a christmas tree is to:

Prevent the release of oil or gas from an oil

well into

the environment

Direct and control the flow of formati

on fluids from the well

When the well is ready to produce oil or gas, valves

are opened and the release of the formation fluids is

allowed through a pipeline leading to a refinery.


Completion


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Oil which

flows from the tubing

is diverted through this

pipe to the main header

and from there

to the process platforms

Top part of the C-section

of well head

Tubing hanger comes upto this point

Lower Master Valve

Upper Master Valve

Crown/ Swab Valve

Wing Valve



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Well Head

Reservoir

Packer

Safety

Valve

Gas Lift

Valve

X-mas Tree

Tubinghanger

Production

Tubing

Perforation

Hydraulic

Control Line

Pump Out

Plug Sump

Oil Well After Completion



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Types of Completion

The types of completion include:

Natural Completions

Natural completions are those in which little or no stimulation is required for production.

Sandstone and carbonate systems with good permeability and mechanical stability areideal for natural completions.

Stimulated Completions

These completions are generally applied to improve the natural drainage patterns of

hard, low-permeability formations. It is used to remove barriers that prevent easy

passage of fluids into the wellbore.

Sand-Control Completions

Sand-control completions support the formation while allowing the flow of fluids. They

are performed in young, unconsolidated or less mechanically competent sandstones.

Completion Process

Completion


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Downhole Equipment

The tubings along with the downhole equipment are lowered into the 95/8 casing of the well.


Completion

Gas Lift Valve

Safety Valve


Pump Out Plug

Packer

Packer

Packer is a device consisting

of a sealing device, a holding

or setting device and an inside

passage for fluids. It expands

externally to seal the well bore.

It helps in blocking the fluids

through the annular space

between the pipe and the wellbore wall. Packers use flexible,

electrometric elements that

expand. It is set hydraulically

from the surface.

X

Completion Process


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Downhole Equipment


Completion

Gas Lift Valve

The gas lift valve is a device installed

on a gas lift cylinder or mandrel. This

device is used to control the flow of

gas between the exterior and interior

of well tubing. It consists of an inlet,

outlet, a main valve, a main chamber

and so on. The design of the side

pocket is such that the componentsthat are installed do not obstruct

the flow of production. This enables

access to the well bore and the

other components of completion.

X

Completion Process

Gas Lift Valve

Safety Valve


Pump Out Plug

Packer


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Downhole Equipment


Completion


Hydraulic control line is a device filled with hydraulic fluid

and connected to a hydraulic fluid source.

Hydraulic control line is used to operate the

safety valve. When the control line is pressurized up to

a certain pressure limit, the safety valve opens.

Its one end connects at the top of the safety valveand the other end to a pressurizing panel at the surface.

It is lowered along with the safety valve while lowering

the tubing string during completion.

X

Completion Process

Gas Lift Valve

Safety Valve


Pump Out Plug

Packer


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Downhole Equipment


Completion

Pump Out Plug

Since the tubing is open at the bottom, the packer cannot be set as the

whole tubing string needs to be pressurized to set it. So a pump out plug(POP) is used for this purpose.

A steel ball is dropped inside the tubing string from the surface. This goes

all the way down and sits on the POP seat at the bottom.

When water is pumped from the top, the ball is pressed against the POP

seat and forms a seal. When pressure in the tubing string reaches a certain

limit, the packer is set. This is indicated in the pumping unit in the form of a

sharp fluctuation of the pressure reading.

Then the pressure is increased, further, to shear the POP seat pins. This is

done to remove the steel ball. When the pins are sheared, the POP seat drops

along with the ball into the well sump.

X

Well Sump

A well sump is the extra bore space below the perforated

zone that allows the collection of junk for example steel ball.

Completion Process

Gas Lift Valve

Safety Valve


Pump Out Plug

Packer


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In a traditional well, components such as valves control the flow of

fluids.

Screens or gravel packs stop sand from entering the well.

Pipe joints and packers needed to ensure the well retains its

integrity over its producing life.

However traditional wells do not respond to changing conditions andall the fluids (oil,gas and water) have to be produced together and

separated at the surface.


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IQ for Intelligent Wells

Intelligent Wells

Automatic Surface Interaction/Continuous

Monitoring/Automatic Flow control/Extensive

Downhole communication

Semi Intelligent Wells

Manual Surface Interaction/Limited

Downhole communication

Conventional

Limited Interaction


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Smart wells offer the possibility to respond to changing conditions.

Smart wells combine existing state-of-the-art technologies such as

wireless technologies,remote sensing capabilities, remote control

mechanism and robotic tools.

Remote sensors can immediately show what is going on in the down

hole.

Valves down the hole can be adjusted, controlling flow or shutting off

production at one level and increasing it from another.

Fluid processing can take place down the hole with gas and liquids

being separated by devices such as hydro-cyclones

Smart Wells


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Drivers

Improved Reliability

Optimum Production leading to longer well and reservoir life.

Optimization of reservoir drainage

No mechanical intervention is required freeing up resources. Lower Operating Cost

Less number of work overs

Decrease Water Production

Better sand control

Increase Reservoir Knowledge Monitoring of fluid/gas contact zone movements

Improved reservoir characterization (saturation, structure,

pressure, temperature)


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Smart Well

Packers

Hydraulic or Electrical Control Lines

SensorsInflow Control Valves ICV

Surface Control Unit (Monitoring and Remote Operation)


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Examples of Controls in Intelligent Wells

Controlling Commingled production

Controlling Down Hole Water Separation

Controlling Down Hole Gas Separation and Re-injection


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Application for Intelligent Wells

Marginal Reserves

Highly Deviated. Horizontal and MLW

Deepwater Wells

High Volume Wells

Shell has about 20 intelligent wells worldwide and is working to increase

that number.

One of its showcase pieces is a well in the North Seas Brent field. The well

produces oil but also has a perforated gas zone up hole thats opened for a

short period each year to meet a gas contract.


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Oilfields

Data

Data

Data

Data

Extract

Clean

Transform

Load

Data Store

Data Warehouse

Interpret

Analyze

Communicate

Decide

Partners,Agencies

Operation

Management


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Reservoir Management Team

Devise Process

Control Methodologies

Life Cycle

Cost and

Benefits

Modeling

Processes

Requiring

Real time

Management

Down hole

Equipment

Design

Monitor Dynamic

Production Data

36887825 basics of well completion ep

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