CT Emergency Procedures

8/8/2019 CT Emergency Procedures

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CoiledTubingEmergencyProcedure Page1/19

Coiled Tubing

Emergency Procedures


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ListofContents

S# HazardScenarioRef# EmergencyProcedure Page

1 HazardScenario#2 CoiledTubingpartsabovetheInjector/Gooseneck 3

2 HazardScenario#3 CoiledTubingpartsbelowPCE 4

3 HazardScenario#4 CoiledTubingLeaks(Pinhole) 5

4 HazardScenario#5 PCELeakEitherAboveorBelowBlindRams 6

5 HazardScenario#6 FailureofCoiledTubingPowerPack 8

6 HazardScenario#7 PipedamagecausedbyInjectorHeadorGooseneck 9

7 HazardScenario#8 FailureofCTReelDrive 10

8 HazardScenario#9 Stuckpipe 11

9 HazardScenario#10 CoiledTubingRunAway 14

10 HazardScenario#11 LeakingBHACheckValves 16

11 HazardScenario#12 LeakinStripperPackOff 17

12 HazardScenario#13 CoiledTubingCollapse 19


3/19


Ref#2.CoiledTubingpartsabovetheInjector/Gooseneck.

a. HaltmovementofCTwithininjector.Setbrakesontheinjectorandtheservicereel.b. StoppumpingoperationsthroughCTworkstringandmonitorCTpressurec. Securewellasrequiredfortheoperationsd. Continuetomonitorwellheadpressuree. Assesssituationtodeterminecourseofaction

IfthereisnoflowthroughCTID, IfthereisslightflowandtheassessmentconcludesthattheCTworkstringcanbesafelymoved, If there is sustained flow and the assessment concludes that CT workstring movement is not

recommended,

f. Openaccumulatorcircuitpressureisolationvalveontheconsole. Closetheslipramsandthepiperams.g. Confirmclosureof theslipramsandpiperams(reportpositionof indicatorpins)andmanually lockthe

ramsassoonassafeworkingconditionspermit.

h. Release injectorbrakeandslackoffbuoyedworkstringweightontotheclosedsliprams. Reset injectorbrake.

i. CuttheCTworkstringusingtheshearrams. Opentheshearramsimmediatelyafterthecutiscompleted.j. PickupCTworkstringapproximatelyonefootwiththeinjectortolocatetheshearedendofCTabovethe

blindramposition.

k. Closethebindramsl. Confirmclosureoftheblindrams(reportpositionofindicatorpins)andmanuallylockwhensafeworking

conditionspermitaccesstotherams.

m. Ensure pressure is bled off above the blind rams. Make provisions to displace hazardous fluids in CTworkstringwithasafeliquidifneeded.

n. RuntheCTworkstring intothewelltopositionthe leakbelowthestripperassemblyandabovethepiperams.

o. Open the accumulator circuit pressure isolation valve on the console. Close the slip rams and the piperams.

p. Confirmclosureoftheslipramsandpiperams(reportpositionofindicatorpins)andmanuallylockramsassoonassafeworkingconditionspermit.

q. InitiatepumpingoperationsanddisplacehazardousfluidscontainedinCTworkstringwithasafeliquid.r. Monitorwellconditionsandwaitoninstructionsfromcompanyrepresentative.


4/19


Ref#3.CoiledTubingpartsbelowPCE

a. Ifa leakoccurs inthetubingbelowthestuffingboxduringdownholeoperations,(usually indicatedbyadrop in pump pressure or loss of string weight), suspend tubing operations and alert the company

representative.Itmustbeassumedthatthecoiledtubinghasaholesomewheredownholeatanunknown

depth.This

circumstance

will

mean

that

at

any

time

during

pull

out

of

the

hole,

the

tubing

could

be

pulled

openendedorleakingoutofthestuffingbox.

b. Clearallpersonnelfromthe immediateareaofthecoiledtubingaroundthe injectorheadandbetweentheinjectorheadandthecoiledtubingreel.

c. Displacethecoiledtubingtowaterandcommencetopulloutofholeatnotmorethan5meters/min(20feet/min).Ensureatalltimesthatallpersonnelareclearoftheimmediateareaasthepossibilityexistsof

pulling the tubing out of the stuffing box. Continue pumping water at a slow rate through the coiled

tubing.

d. Whentheleak inthecoiledtubingappearsabovethestuffingbox,stoptheinjectorandholdtheleakingsectionofcoiledtubingbetweenthechainsandthestuffingbox.

e. Inspecttheleak.Iftheleakisminor,continuetopulloutofhole,beingcarefulasthetubingisbeingbentoverthegooseneckandontothereelascatastrophicfailuremayoccur.

f. Iftheleakismajor,orthetubingisactuallyseveredorthewellborefluidsareescapingthroughthetubing,proceed,cutthetubingandshuttheblindrams.


5/19


Ref#4 CoiledTubingLeaks(Pinhole)

LeakinCoiledTubingAtSurface

Calllocalalert(siteandunitspecific)andensureallpersonnelareremovedfromtheoperational area. Inparticular

make

sure

all

personnel

remain

clear

of

the

area

between

the

injector

head

and

the

coiled

tubingreel.

Iftheleakissmallorapinholeleak,pulloutoftheholeslowlyandpositiontheleakonthelowerpartofthe coiled tubing reel as soon as possible. Be careful when area of the leak is bent onto the reel as

catastrophicfailuremayoccur. Makearrangementstohaveawaterhosepresenttowashawayanyfluid

from thereelwhichmaybehazardous. Makearrangementstostartpumpingwater throughthecoiled

tubing reel. Depressurize reel as much as conditions allow without exceeding collapse limitations of

tubing.

Notifythecompanyrepresentativeoftheproblemanddeterminethebestmethodtomaketheareasafe.Iftheleakisminorandwatercanbedisplacedtotheleak,continuetopulloutoftheholeandchangethe

reel.

Iftheleakisconsideredtobetooserioustodisplacetowaterandpulloutofhole,oruncontrolledleakageofhydrocarbonsorhazardousmaterialspreventsthis(i.e.checkvalvesnotholding),setthecoiledtubing

slipsandpiperamsandactivatethecutters.Pullthecoiledtubingstubpiececlearoftheblindrams,then

activatetheblindrams(manuallylockinplace).

Depressurizethecoiledtubingreelthroughtheriser. Ifhydrocarbonsarepresentinthereel,displacethereeltowaterandemptythecontentsviatherisertospecifiedsafedisposalarea.

CommencefishingthecoiledtubingheldintheBOPs. Seesectiononfishingoperations.LeakInCoiledTubingBelowSurface

Ifa leakoccurs inthetubingbelowthestuffingboxduringdownholeoperations,(usually indicatedbyadrop in pump pressure or loss of string weight), suspend tubing operations and alert the companyrepresentative. It must be assumed that the coiled tubing has a hole somewhere downhole at an

unknowndepth. Thiscircumstancewillmeanthatatanytimeduringpulloutofthehole,thetubingcould

bepulledopenendedorleakingoutofthestuffingbox.

Once thecompanyrepresentativehasbeenalerted,clearallpersonnel from the immediateareaofthecoiledtubingaroundtheinjectorheadandbetweentheinjectorheadandthecoiledtubingreel.

Displace the coiled tubing to water and commence to pull out of hole at not more than 15 ft/min (5meters/min). Ensureatalltimesthatallpersonnelareclearoftheimmediateareaasthepossibilityexists

ofpullingthetubingoutofthestuffingbox. Continuepumpingwaterataslowratethroughthecoiled

tubing.

Whentheleakinthecoiledtubingappearsabovethestuffingbox,stoptheinjectorandholdtheleakingsectionofcoiledtubingbetweenthechainsandthestuffingbox.

Inspecttheleak. Iftheleakisminor,continuetopulloutofhole,beingcarefulasthetubingisbeingbentoverthegooseneckandontothereelascatastrophicfailuremayoccur.

Iftheleakismajor,orthetubingisactuallyseveredorthewellborefluidsareescapingthroughthetubing,cutthetubingandshuttheblindrams.


6/19


Ref#5PCELeak

5.1RotatingJoint

Closethereelisolationvalveinsidethepowerreelandrepairorreplacetherotatingjointasrequired.Retest

andresume

operations.

5.2LeakBelowtheBlowOutPreventer

Iftheleakisminor,coiledtubingisintheholeandtheshear/sealramsarebelowtheleak:

Callalocalalertandnotifytheoilcompanyrepresentative. Clearallnonessentialpersonnelawayfromthearea. HookupthepumpertothekilllineoftheBOPandpumpfreshwaterslowlydowntheannulus.

Note:Avoidcollapsesituation.

Continuetopulloutoftheholeandmonitorthesituationclosely. Closetheswabvalveandblindramsoncethecoiledtubingisintheriserandrepairtheleak. Performareinstatement testonsurfaceequipmentaftertheleakhasbeenrepaired.Ifthecoiledtubingisinthewellandnoshear/sealramsbelowtheleak,ortheleakisconsideredserious:

Callalocalalertandnotifytheoilcompanyrepresentative. Ensurethatallpersonnelareremovedfromthearea. Ensurethatthecoiledtubing issufficientlyoffbottomsothatwhentheshearsealramsareactivatedthe

pipewilldropbelowtheXmastreemanualmastervalve. Ifatallpossible,thedecisiontocutthetubing

andactivatethesystemwillbetakenbytheoilcompanyrepresentative inchargeoftheoperation. This

may not always be possible. If the situation is extremely dangerous and requires a quick decision, the

coiledtubingsupervisorinchargeshouldmakethisdecision.

Closetheshear/sealrams inthesafetyheadtocutthepipeandallow ittodrop. (Iftheshear/sealramshaveseparateshearandblindrams,closetheshearramstocutthepipe,pullupthecoiledtubingandclose

theblindrams).

Close

the

swab

valve

on

the

Xmas

tree.

ClosethemastervalveontheXmastree. Repairtheleakandpressuretesttheriser. Planfishingoperations.5.3 LeakintheCoiledTubing(AbovetheStripper)

VeryhighcompressiveloadscanbeachievedwhenfirststartingtoRIHwithcoiledtubing,soextremecare

shouldbetakentopreventcrumplingthecoiledtubing.

a. Stopmovingthecoilandshutdownthepump.

b. Inspectthehole.Ifitisapinhole,orifthereisonlyminimalleakageorflow,continuetopulloutofthe

hole.Placingtheleakontothedrumwillhelpcontainthespill.

c. Iftheholeislargeandleakssignificantly,itmaynotbepossibletocontinuespoolingthecoiledtubing.If

thecheckvalvesholdpressure,thedamagedsectionofthecoiledtubingcanbecutandreconnectedto

continuespooling.Ifthecheckvalvesdonotholdoriftheyhavenotbeenused,pickupoffbottom,set

theslipsandcutthecoiledtubingwiththeshearrams(Note:Usethe lowerblind/shearramsifthere

aretwosetsinthewellcontrolstack).

d. Pickthecoiledtubingupabovetheupperblind/shearramandclosetherams.


7/19


e. Initiateakillprocedurethroughthekill line(downthecoiledtubing lefthanging intheslips)toeliminate

thesurfacepressure.

f. Whenthewellisdead,pulloutoftheholeandrepairorreplacethecoiledtubingstring,

Note:If

there

is

acid

in

the

coil,

it

should

be

displaced

to

the

wellbore

with

water

while

pulling

out

of

the

hole.


8/19


Ref#6.FailureofCoiledTubingPowerPack

Ifthehydraulicpowerunitbreaksdown,theinjectorheadwillceasetofunctioninafailsafecondition. Asthe

hydraulicpressurereducestozerothemotorbrakeswillcomeonandholdthetubing. Ifthissituationoccurs:

Ensure injector brakes are supporting the tubing. If for some reason there is some doubt as to theinjectorsabilitytodothiseitherduetoafaultybrakeoraleakinthe insidechaintensionsystem,closethetubingslipstoholdthecoiledtubing. Manuallylockwithhandwheel.

NOTE:theuseofthetubingslipswillcausesomelocalizeddamagetothetubingandforthisreasonthis

courseofactionshouldonlybetaken ifthere issignificantdoubtaboutthe injectorsabilitytoholdthe

string.

Closethepiperamsandmanuallylockinplace. Chainthetubingreeltopreventthetubingfromunspooling. Thisshouldonlybedoneintheeventthat

thereelbrakefailsorthereisleakageinthereelmotorsystem.

Maintain

circulation

if

required

Repairorreplacethepowerpack.NOTE: if replacing the power pack, ensure that the BOP accumulator on the replacement unit is fully

chargedbeforechangingover.

Equalizethepressureacrossthepiperamsandopentheslips. Iftheslipramswereactuated,pickupthecoiledtubingandinspecttheareaaroundwhichslipswereset.

Cleanandpolishthesurfacewithemerycloth. Ifthetubingisseriouslydamagedpulloutofthewelland

repairorreplacethestring.


9/19


Ref#7PipedamagecausedbyInjectorHeadorGooseneck

a. HaltmovementofCTwithininjector.Setbrakesontheinjectorandtheservicereel.b. StoppumpingoperationsthroughtheCTworkstringc. Securewellasrequiredfortheoperationd. Assesssituationtodeterminecourseofactione. Confirm the reduction in weight indicator reading and that the CT segment has fallen below the blind

rams.

f. When separated CT segment falls through stripper assembly and below the blind ram position, openaccumulatorcircuitpressureisolationvalveontheconsole. Closetheblindrams.

g. Confirmclosureoftheblindrams(reportpositionof indicatorpins)andmanually lockramsassoonassafeworkingconditionspermitaccesstotherams.

h. ClosecrownvalveonChristmastree.Countnumberofvalvehandleturnstoconfirmproperclosure.i. Monitorwellconditionsandwaitoninstructionsfromcompanyrepresentative.


10/19


Ref#8FailureofCTReelDrive

Ifthedriveislosttothecoiledtubingreel,itisnolongerpossibletomaintainbacktensiononthecoiledtubing

betweentheinjectorheadandthereel. Theeffectofthiswillbeforthereeltounspoolandforthetubingon

thereeltoattempttounravelandadoptacurvature largerthanthereeldiameter. Thepotentialdangerof

thissituation

is

that

any

personnel

in

the

vicinity

of

the

tubing

could

be

struck

by

the

unraveling

coiled

tubing.

Inthissituation:

j. Callanalert(siteandunitspecific).k. Immediatelystoptheinjector.l. Ensurethatthecoiledtubingissecurelyheldbytheinjectorandcloseandlockthetubingandsliprams.m. Applythetubingreelbrakeiffitted.n. Inspectthecoiledtubingreelandeffectrepair. Inspectthecoiledtubingfordamage.o. Ifthecoiledtubingisdamaged,proceedaspercoiledtubingleakonsurfaceSectionp. Oncethereeldrivemechanismisoperational,runthetubingintheholeasfaraspossibletoremovethe

unwrappedtubing

from

the

reel.

(applying

tension

will

not

re

tighten

the

tubing

beyond

the

top

wrap)

Do

notrunanykinkedtubingintothewell.

q. Onceall theunwrapped tubinghasbeenremoved from thereel,pulloutof theholespooling thepipecorrectly.

r. Ifitisnotpossibletorunthetubingfurtherintothewell,anditisnotpossibletospoolthetubinginthewell back onto the reel, (no surplus capacity on reel) then it will be necessary to cut the tubing and

continueasperLeak inCoiledTubingAtSurfacesectionAfterthisaction itwillbenecessarytofishthe

tubingandspoolitontoanotherreelwithsufficientcapacitytoholdthetubingstillinthewell.


11/19


Ref#9StuckPipe

Whenthepipe isunabletobemovedfreelywithaforceof80%ofthetensileyield,thepipe isstuckdueto

one of two reasons. Friction sticking is due to tortuous wellbore or buckled production tubing. Mechanical

stickingcanbetheresultofsolidsaccumulationaroundthecoiledtubingordownholetoolsbecominglodged

inthe

completion.

9.1.FrictionStuckCoiledTubing

Preventingfrictionstuckcoiledtubingbeginsinthejobplanningbyidentifyingwellborepathsthathaveareas

of dogleg severity (DLS) that can inhibit the free movement of pipe. Normally a relatively high DLS (10 15

deg/100)canbetoleratedif itexistsinan isolatedarea.However, iftheyarewidespreadinthecompletion,

even a moderate DLS can frictionally stick the coiled tubing. The drag weigh forces can be modeled to

determineiftherewillbeaproblem.Whileperformingtheoperation,frequentweightchecks(each500)will

helpidentifyaproblembeforeitbecomessevere.Thiscanalsobeaproblemindualortriplecompletionseven

ifthereisnoobviousDLSproblem.

a. Apply80%ofthetensileyieldtothepipeandmaintainthatforceforaminimumof30minutes.b. Ifpossible,continuetomaintaincirculationbypumpingatlowratepressuretominimizethecoiledtubing

pressure.

c. Pumpfrictionreducingadditivessuchaspolymergeldieselorbeadsdownthecoiledtubingordownthecoiledtubingproductiontubingannulus.IfpumpingdowntheCT/PTannulus,limitthepressurebelowthe

collapseratingofthecoiledtubing.

d. Displacethewelltoheavierfluidtoprovideincreasedbuoyancy.e. Additional buoyancy can be achieved by displacing the coiled tubing to nitrogen. Note that collapse

pressureconditionshaveincreasedwhenchangingthefluid/gasdisplacementofthewellboreandcoiled

tubing.

f. Mechanicalmovementcanbeinducedwithouttheuseofhydraulicjarsinthetoolstring.

9.2MechanicallyStuck

Iftheweight indicator loaddoesnotdecreaseafterapplyingatensile loadofupto80%ofpipetensileyield

rating,itislikelythatthecoiledtubingismechanicallystuck.Attempttolowerthecoiledtubingintothewell

todetermine if it isactuallystuckatthatpointor if it isunabletopassthrougharestrictionorupset inthe

completionpipe.

Ifthecoiledtubingcanbemoveddownward,thendeterminethefollowing:

a. Ifthepipe(ortools)couldhavebeenbentorbuckledbysettingdownexcessiveweightorrunningintoan

obstruction.

b. Review the well sketch for any obstructions or restrictions that may present problems for movement of

coiledtubingordownholetools.

c. Mechanicalmovementcanbeinducedwithouttheuseofhydraulicjarsinthetoolstring.


12/19


Thefollowingoptionsmayexisttoretrievethecoil:

a. Continuecirculationifpossible.

b. Workthecoilintheoppositedirectionfromthewayyouweregoing,whenitwasdiscoveredthecoilwas

stuck.If

afew

feet

of

progress

is

made

in

that

direction,

begin

working

the

coil

back

the

other

way.

Try

workingthecoildownafewfeet,andthentrytheupdirectionagain.Graduallyincreasetheoverpullorset

downweightineachcycleratherthangoingtomaximumsallatonce.

c. Often times coil circulation is lost to thesurface due to the solids buildup. If circulation canbe attained

acrossthesolidsbuildup,considerpumpingahighviscositysweeptohelpstringthesolidsout.Thegoalis

tostringoutthesolidstoreducethefrictionloadsothecoilcanbemoved.Asandarcharoundthecoil

hastremendousgrippingpower.

d. Avoidworkingthecoiloverthegooseneckwithhighcoilpressure,asthisdrasticallyreducesthenumberof

cycles that can be performed before suffering permanent coil fatigue (ballooned pipe). Check the coil

history to get an idea how much the coil, which is currently across the gooseneck, has been worked on

otherjobs.Takecarefulnoteofanypriorfishingjobsorstimulations wherethecoilhasbeenreciprocated

manytimes.

e. Try to increase the differential hydraulic pressure across the solid bridge by flowing the well harder,

increasinggasliftorsurgingthewellwhilecontinuingtoworkthecoil.

f. Iffluidcanbeinjected,considerpumpingingasornitrogendownthetubingcoiledtubingannulustoform

agascap.Thensurgethewelldownthewingvalvetoapplyahighupwarddifferentialpressureacrossthe

problemdebris,againwhileworkingthecoiledtubing.

g. Iffluidcanbeinjecteddownthecoiledtubingtubingannulus,thiscanbeusedinconjunctionwithworking

thepipe.Avoidpumpingatpressuresclosetothecollapseratingofthecoiledtubing.

h. Always keep track of coiled tubing cycles over the gooseneck. Do not work the pipe excessively if no

progress isbeingmade.Worktochangethedownholeconditionsto increasethechancesoffreeingthe

pipe.Then

resume

working

the

pipe

again.

i. Onceprogressismade,alwayscontinuecirculatingwhileworkingthepipebackuptheholeslowly.

j. Consideration can begiven to spottingacid across theproblem debris if you feel it is evenpartiallyacid

soluble.

k. A minor mechanical movement canbe achieved without the use ofjars by removing one of the three

pump suction valves from the triplex pump to induce hydraulicjacking through the coiled tubing. The

pulses created can contribute to solving both mechanical or friction stuck coiled tubing. However, this

option should be used with caution due to the inherent cycling effects imposed on the coiled tubing at

surface.

Ifthe

coil

cannot

be

retrieved:

l. If there is a tool string that can be released, pump a ball to release the hydraulic disconnect if it is

determinedthattheBHAisgettinghungup.

m.Killthewell,cutthecoiledtubingatthesurfaceandrunafreepointtooltodeterminethedepthtothe

stuckpoint.Follownormalfishingprocedurestoremovethecoiledtubing.


13/19


9.3 MechanicallyStuckwithoutCirculationa. Pump the kill weight fluid down the coiled tubing. If it is not possible to pump down the coiled tubing,

attempttopumpthekillweight fluiddown theannulus(atpressuresbelow thecollapsepressureofthe

coiledtubing).

b. Cutthecoiledtubingatsurfaceandrunafreepointtool.Follownormalfishingprocedures.


14/19


Ref#10CoiledTubingRunAway

10.1UncontrolledDescentofCoiledTubing

a. Applyadditionalpressuretothestripperassemblyandsimultaneously closethepiperams.

b. Increase the velocity of the chains (in the same direction as the pipe) to closer match the speed of the

coiled tubing Tailing into the well.This will help relieve the loss of friction between the chains and the

pipe.Attempttoincreasetheinjectorsinsidechainpressuretostoptheuncontrolledmovementofpipe.

c. Once the pipe has stopped falling through the chains, slowly reduce the chain speed and come to a

completestop.

d. Closetheslipramsandmanuallylockthem.

e. Oncethepipehasstopped,closethepiperamsandinspectfordamagetothechainsorpipe.

f. Observe pump pressures and circulation rate to determine if there is any damage to the bottom of the

coiledtubing,suchasacrimp,kinks,orbuckling.

g. Pumpthehydrauliccylindersopenontheinjectorchainskates.

h. Inspectthechainblocksandremoveanydebris.

i. Reset the inside (and outside) chain pressures to the proper settings. Verify the proper alignment and

spacing between the chains. If necessary, replace the chains or individual gripper blocks as necessary to

preventdamagetothecoiledtubingwhilepullingoutofthehole.Ifnoadditionalchainsorgripperblock

inserts are available, the chains can be material on site to facilitate better grip. (Use material such as

sodiumchloride,potassiumchloride,sand,etc.)

j. Ifthewellisundercontrolandtherearenomechanicalproblems,thenopenthepiperamsandsliprams.

Changethestripperelementifnecessary.

k.

Pull

out

of

the

hole

slowly

to

determine

if

the

end

of

the

coiled

tubing

can

be

pulled

inside

of

the

production tubing. Pull completely out of the hole to inspect the coiled tubing completely for external

damagethatmayhavebeencausedbytheslipsorchainsduringdescent.


15/19


10.2 UncontrolledAscentOutoftheWell

a. Applyadditionalpressuretothestripperassemblyandsimultaneously closethepiperams.

b. Increasethevelocityofthechains(inthesamedirectionasthepipe)toclosermatchthespeedofthe

coiledtubing

falling

into

the

well.

This

will

help

relieve

the

loss

of

friction

between

the

chains

and

thepipe.Attempttoincreasetheinjectorsinsidechainpressuretostoptheuncontrolledmovement

ofpipe.

c. Iftheseattemptsareunsuccessfulputtheinjectormotorsinneutralandclosethesliprms.

d. Oncethepipemotionishalted,closethepiperamsandslips,ifnotalreadyclosed.

e. Pumpthehydrauliccylindersopenontheinjectorchainskates.

f. Inspectthechainblocksandremoveanydebris.

g. Resettheinsideandoutsidechainpressurestothepropersettings.

h. Ifthewellisundercontrolandtherearenomechanicalproblems,thenopenthepiperamsandslip

rams.Changethestripperelementifnecessary.

i. Reduce the hydraulic pressure on the stripper element and pick up the coiled tubing enough to

inspecttheareasofpipeheldbytheslips.

j. Determine whether it will be necessary to repair/replace that section of coiled tubing prior to

resumingthepipeextraction.Beextremelycautiouswhilecheckingtheareaofpipeheldbytheslips

sincethepipemaybeweakenedandmayfailwithhighsurfacepressurepresent.

k. Continuetopulloutoftheholeandclosethemastervalve.Determinethecausefortheuncontrolled

movement of pipe prior to entering the well again. Replace or repair the coiled tubing string as

required

If thecoiled tubing isblownoutof thestripperassembly,close theblindramsandmastervalveas

quicklyaspossible.


16/19


Ref#11LeakingBHACheckValves

a. Ifaleakoccursinthetubingbelowthestuffingboxduringdownholeoperations,(usuallyindicatedbyadrop in pump pressure or loss of string weight), suspend tubing operations and alert the company

representative. It must be assumed that the coiled tubing has a hole somewhere downhole at an

unknowndepth.

This

circumstance

will

mean

that

at

any

time

during

pull

out

of

the

hole,

the

tubing

couldbepulledopenendedorleakingoutofthestuffingbox.

b. Oncethecompanyrepresentativehasbeenalerted,clearallpersonnelfromthe immediateareaofthecoiledtubingaroundtheinjectorheadandbetweentheinjectorheadandthecoiledtubingreel.

c. Displace the coiled tubing to water and commence to pull out of hole at not more than 15 ft/min (5meters/min). Ensure at all times that all personnel are clear of the immediate area as the possibility

existsofpullingthetubingoutofthestuffingbox. Continuepumpingwaterataslowratethroughthe

coiledtubing.

d. Whentheleakinthecoiledtubingappearsabovethestuffingbox,stoptheinjectorandholdtheleakingsectionofcoiledtubingbetweenthechainsandthestuffingbox.

e. Inspect the leak. If the leak is minor, continue to pull out of hole as in BOP emergency operationssection,beingcarefulasthe tubing isbeingbentoverthegooseneckandontothereelascatastrophic

failuremayoccur.

f. If the leak is major, or the tubing is actually severed or the wellbore fluids are escaping through thetubing,cutthetubingandshuttheblindrams.


17/19


Ref#12 LeakinStripperPackOff

Stripper leaks are a common occurrence and are affected by many factors such as stripper hardness, coil

smoothness, effectiveness of the coil lubrication system, and the stripper pressure that is used. Without

adequatelubrication,stripperscancompletelygripthecoilwhilegoinginthehole.Thiscancausecoilfailure

betweenthe

stripper

and

the

injector

head

chains.

The

standard

coil

lubrication

procedure

used

to

consist

of

lubricating the coil with diesel at the spool. To reduce the environmental impact of dripping diesel on the

ground,thestripperhousingcanbeandfittedwithasmalllubricationorifice,solubricationcanbedoneright

atthestripper.Thishastheadvantageofplacingthe lubricationwhere it isneededandthedisadvantageof

notbeingabletovisuallyverifyadequatelubrication.

12.1SmallStripperLeaks

Ifasmallleakdevelopsthestripperpressurecanbeincreaseduntilitstops.Donotallowevenasmallleakto

continue,becauseitwillcuttheelementsandbecomemoresevere.

If the leakcannotbestoppedbystripperhydraulicpressure,and thecoilcannotbepulledout, thestripper

shouldbechangedoutimmediately.

StripperReplacement

a. Notethecurrentstringweight,settheslipsonthecoil,andeitherslackoffcoilweightorpickup(depending

uponwhethercurrentweight ispositiveornegative)from30005000Ibstobesuretheslipsareholding.

Manuallylockintheslips.

b. Setthetubingramsandbesuretheramsareholdingbybleedingoffabovethem.Manuallylocktherams.

c. Bleedoffthepressureinthewellcontrolstackthroughthekillline.

d. Changeoutthestripperasperthemanufacturersprocedure.

e. Energize it to the proper pressure setting based on the wellhead pressure. The stripper can be pressure

testedby

pumping

through

the

kill

line.

f. Equalizethelubricatorpressurewiththewellheadpressure.

g. Unlock and open the tubing rams. Set the string weight to the previous value and unlock and open the

tubingslips.Proceedwithnormaloperations.

12.2 ORingLeaks

IfanOringorchevronsealbetweentheBOPstackandthestripperfails,alwaysclosethetubingramsfirst.

Thecoildepthandleakseverityshouldbeconsideredwhendeterminingthenextstep.

a. Stopthecoilandnotethecurrentstringweight,settheslipsonthecoil.

b. Setthetubingramsandmanuallylock.Bleedoffthelubricator.

c. BackoffthequickunionwheretheOringisleakingandwalktheinjectorheadupthetubing,byoperating

theinjectors ifrunningthecoil intheholeslowly,whileraisingthetrolleyhoist,tohelpsupportthetotal

injectorheadandguidearchweight.

d. Repair theOringwith astandard Oring patch kitor if aspareOring isalreadyon the lubricator,roll it

downintoplace.


18/19


e. Walktheinjectorheadbackdownandmakeupthequickunion.NewOringtoavaluecomparabletothe

currentwellheadpressure.

g. Setthestringweighttotheoriginalsetting.Unlockandopentheslips.

h.Equalize

across

the

tubing

rams

and

open

them.

Pull

out

of

the

hole

to

change

out

the

patched

O

ring.

If

aspareOringwasrolledintoplace,continuewithCTUwork.


19/19


Ref#13CoiledTubingCollapse

a.Killthewellifitisnotalreadydead.

b.Releasethestripperelementpressure,andremovethestripperelementsandretainingbushings.

c.Pickupthecoiledtubingslowlytodeterminethetopofthecollapsedpipe.

d. Run back into the hole with the coiled tubing until the undamaged portion of the pipe isacross thewell

controlstackcomponents.

e. Closethepipeandsliprams,andmanuallylock.

f. Relaxtheinjectorchainstoverifythattheslipramsareholding.

g. Cutthecoiledtubingabovetheinjector.

h. Opentheinjectorchains.Removetheinjectorfromthecoiledtubing,andsetitofftotheside.

i. Attachafulltubeclamptothecoiledtubingdirectlyabovethewellcontrolstack.

j. Connectthecraneortravelingblocktotheclampandopenthepipeandsliprams.

k.

Slowlypull

the

coiled

tubing

out

of

the

well

to

the

maximum

height

of

the

crane

or

block.

l. Attachacollapsedtubeclamptothecoiledtubingdirectlyabovethewellcontrolstack,andcutthetubing

abovethebottomclamp.Connectthecrane,andpullthecollapsedcoiledtubingoutofthewell.

m.Continuealternatingpulling,clamping,andcuttingthecoiled tubinguntilallofthecollapsedsectionhas

beenremovedfromthewellandthetransitionsectiontoundamagedpipeislocatedabovethewellcontrol

stack.Ensurethatthereisenoughcompetentpipeabovethewellcontrolstacktothreadthecoiledtubing

throughthestripperandinjector.

n. Closethesliprams,andremovetheclamp,

o. Install and secure the injector onto thecoiled tubing. Apply hydraulic pressure to the inside chains, and

switchtheinjectortotheextractionmodeOpenthesliprams.

p. Either connect the end of the coiled tubing to the other section of coiled tubing on the reel with a

connectoror

install

avalve

onto

the

end

of

the

coiled

tubing

and

begin

anew

wrap

on

the

reel.

q. Reinstallthestripperbushingsandelements.

r. Finishpullingoutofthehole,andreplacethereel.Determinethecauseofcollapsepriortoenteringthe

wellagain.

Documents

CT Emergency Procedures