3. Cleanout
The removal of wellbore-fill material such as
sand , scale or organic materials , and other
debris from the wellbore . Many reservoirs
produce some sand or fines that may not be
carried to surface in the produced fluid .
Accumulation of fill material may
eventually increase in concentration within
the lower wellbore possibly restricting
production .
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5. Mill
Before defining mill , we need to know what
is junk ! . Junk is anything in wellbore that is
not supposed to be there . The term is
usually reserved for small pieces of steel
such as hand tools , small parts , bit nozzles ,
pieces of bits or another down-hole tools. A
mill is usually used to remove junk in the
hole or to grind away all or parts of casing
string .
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6. In the case of junk , the metal must be broken
into smaller pieces to facilitate removal from
the wellbore so that drilling can continue .
When milling casing , the intent is to cut a
window through the side of the casing or to
remove a continuous section of the casing so
that the wellbore may be deviated from the
original well through the window or section
removed depending on the type of grinding or
metal removal required . The shape of the
cutting structures of mills varies .virtually all
mills, however utilizes tungsten carbine cutting
surfaces.
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7. So , It’s time to talk about something allows
fill material cleanout , mill and other very
important uses .
Coiled Tubing
- Definition
-main component
-uses & advantages
-Disadvantages
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8. Definition
Coiled tubing refers to a continuous length of
small diameter steel pipe and related surface
equipment as well as associated drilling ,
completion and work over or remediation ,
techniques . Coiled tubing oilfield technology
was initially developed for working on live ,
producing wells . More recently , this
technology has gained wider acceptance . The
trend toward extended reach wells favors
coiled tubing for its ability to drill or convey
tools and equipment in high angle wellbores .
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9. Main component
1.Injector and tubing guide arch
2.Service reel with CT
3.Power supply / Prime mover
4.Control console
5.Control and monitoring equipment
6.Downhole CT connectors and bottom-hole
assembly(BHA)
7.Well-control stack equipment
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11. Power pack unit
Provides hydraulic power to control and operate a coiled tubing unit
and pressure control equipment “ has independent electric or
diesel power source”
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12. Control unit
Control unit is located behind a coiled tubing reel “ or any location that is
safe when operating the unit “ . Level of control and instrumentation
depend on the type of operation being performed .
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13. Injector head
Consists of several hydraulic systems that allow a coiled tubing
unit to operate with a high degree of operational variability . Its
function “ Pulling and pushing “ .
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14. Coiled tubing reel
Main function; store a coiled tubing . It’s hydraulically driven . A reel
driven system is designed to keep the coiled tubing in a dynamic
tension between gooseneck and the reel . Its capacity depends on
tubing size , weight and length of coiled tubing14
15. CT BOP
The BOP is used to secure the coiled tubing and isolate the wellbore
pressure during normal and emergency situations . Consists of
Blind ram , Shear ram , Slip ram and pipe ram
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16. Functions or uses
Innovative services conveyed on CT are designed to improve
your well and reservoir performance .
Applications
Matrix and fracture stimulation
Wellbore cleanout
Logging
Perforating
Nitrogen kickoff
Sand control
Drilling ‘’highly deviated and horizontal wells’’
Cementing
Well circulation
Mechanical isolation
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18. DTS
Surveys to guide fluid placement and
identify zones for acid stimulation . With
selective diversion stages temporarily
sealing off treated zones to ensure effective
stimulation of all targeted intervals .
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20. Nitrogen kickoff
The most popular use for coiled tubing is
circulation or deliquification . A hydrostatic
head may be restricting flow of formation
fluids due to its weight “ well is said to be
killed “ . The safest , not cheapest , solution
would be to attempt to circulate out the
fluid using a gas “frequently nitrogen” often
called Nitrogen kickoff and allow cleaning
the hole .
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21. Tool conveyance
Coiled tubing fishing and milling
Down-hole valve manipulation
Blasting service
Zonal isolation
CT logging
CT drilling
Control
flow from
various
zones
Real time
data
Acid wash,
scale removal
Separation of
zones via
packer
Enable horizontal
drilling
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22. Coiled tubing drilling
A relatively modern drilling techniques
involves using coiled tubing instead of
conventional drill pipe . This has the
advantage of requiring less effort to trip in
and out of the well “ the coil can simply be run
in and pulled out while drill pipe must be
assembled and dismantled joint by joint while
tripping in and out”
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23. Instead of rotating the drill bit by using a
rotary table or top drive at the surface . It’s
turned by a down-hole Mud motor ,
powered by the motion of drilling fluid
pumped from surface . Drilling which is
powered by mud motor instead of rotating
pipe is called slide drilling .
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24. Coiled tubing logging
Coiled tubing allow directional surveys ,
gamma ray , pressure and temperature
measurements.
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25. Coiled tubing production
Coiled tubing is often used as production
string in shallow gas wells that produce
some water . The narrow internal diameter
results in a much higher velocity than
would occur inside conventional tubing or
inside casing . This higher velocity assists in
lifting liquids to surface .
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26. DisadvantagesAdvantages
Fatigue life limitNo rig required
Pressure and tensionNo connections – fast
Diameter and ovalityMoney saving
More tortuous pathPumping flexibility
fluid placement
Reduced formation
damage
Allow MPD & UBD
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