lecture of ch. 6, 7, 8
TRANSCRIPT
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Ch. 6. Cuttings transport (hole cleaning) Introduction
1. Vertical wells high c
2. Medium inclined wells avalanches
3. Highl inclined wells !ed " dunes
1. Practical transport mechanisms, including string rotation
2. Theoretical transport mechanisms, without string rotation
3. Practical problems
4. Practical solutions
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6. Cuttings transport6.1. Vertical wells
#ettling o$ cuttings
qcuttings
= /4 * dbit
2* ROP (m3/s)
ccuttings,0
= qcuttings
/ (qpump
+ qcuttings
) qcuttings/ qpumps
Settling, vslip, will lead to increased concentration
vtransport= vann- vslip
vslip == 0
vann= 0.15 m/s
c = 0.02
vslip= 0.0 m!s
vann= 0.15 m/s
c = "
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0= am
( )shp!sph!mudp "#g =
#g = #shear
( ) sph!mudp "gmm = 3363
4psph! d!#
==
224 psph! d!" ==
=dvx
dr
/ 2 / 2
2 / 2 2
p!iph!$ p!iph!$
slip cnt!%& sph!
v l tv !
v v ! t !
= = = =
02
slip' '
slip
p
vv dv
v! d! ! d
= = =
( )2
3
24
6
= p
p
slip
pmudp
d
d
vdg
( )
6
2
mudpp
slip
gdv
=
6. Cuttings transport6.1. Vertical wells
#ettling o$ cuttings
slip' vv2=>
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c or
6. Cuttings transport6.1. Vertical wells
#ettling o$ cuttings % &$$ect o$ particle concentration
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ccuttings= ccuttings,0! $transport
vtransport= vann- vslip
Rtransport= vtransport/ vann= 1 - vslip/ vann
%hec& vslip '
vslip, 0.00 = .00 2(2 00 .1100)*.+1!(0.1 ..) = 0.1+ m!s
- eect o c and vslip= 0.10 m!s
/ample o determining necessar '
c0.04 and $P = 10 m!hour (30 t !h)
vann= "
ecessar pump low rate = v5 = !4 .(12. 26 2) .0.024 2
=
6. Cuttings transport 6.1. Vertical wells
#ettling o$ cuttings % &$$ect o$ particle concentration
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0
=am
#7rag = #g
= Vp(p- mud)g
CDrag
Ap0.5
mudv
slip2
= vslipdpmud/eff
6. Cuttings transport 6.1. Vertical wells
#ettling o$ cuttings % &$$ect o$ particle concentration
CDrag
=
4 .10-7(2400 1400) .10
/ (2.5 . 10-4.0.5 .1400 .0.12) = 1.6
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= spherisit= area o sphere o same volume ! area o cuttings
= 5sphere! 5cuttings
d1
d3
d2
dsphere
1.1
1.0
0.+2
0.+0
0.0
0.48
0.42
0.0*
0.04
d1= 4
d2= 10
d3= 10
6. Cuttings transport 6.1. Vertical wells
#ettling o$ cuttings % &$$ect o$ particle concentration
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6. Cuttings transport
6.2. Medium inclined wells % 3' 6' 'inclination
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"M
6. Cuttings transport
6.3. Highl inclined wells
1. *eal transport mechanism
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"M
6. Cuttings transport 6.3. Highl inclined wells
1. *eal transport mechanism
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' '.+ 1v (m,s)
1.'
'.+
'.'
-ransport e$$icienc
18. large holes 1+0 rpm ideal 000 lpm
12.2 med holes 120 rpm min 3 000 lpm
+. small holes 120 rpm ideal 2 000 lpm
6. Cuttings transport 6.3. Highl inclined wells
1. *eal transport mechanism
6 C tti t t
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ma.i$
holecl
eaning
isprior
it
ma.i$&C/
ispriorit
"M
6. Cuttings transport 6.3. Highl inclined wells
1. *eal transport mechanism
6 C tti t t
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2
2
8
'
p
(!ag(!agv
d)*
=
2
2
8'
p
+i&t+i&t vd
)*
=
( )( )
sincossin2/2
2
2
+= $pc%hsivd
*
( )&luidsp
g
dg*
=6
3 = angle o repose= inclinaiton (devation rom vertical)
a. General
b. Drag
6. Cuttings transport 6.3. Highl inclined wells
2. Model0 Mechanistic approach
6 Cuttings transport
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2
2
8'
p
i&ti&t vd
)*
=
( )( )
sincossin2/2
2
2
+= $pc%hsivd
*
2
Re282.5
=d!
dv
v
d) '
p'
p
i&t
, sin 0
nt li&t + c%hsiv* * * , = >
[ ], sin ( ) cos sin( ) 02
p
nt !%lling ( + c%hsiv
d* * * * , = + + >
c. Lift
d. Cohesive
e. Conclusion
6. Cuttings transport 6.3. Highl inclined wells
2. Model0 Mechanistic approach
6 Cuttings transport
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6. Cuttings transport 6.3. Highl inclined wells
2. Model0 &mpirical approach
6 Cuttings transport
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Volume
#weep
Volume
"M
6. Cuttings transport 6.3. Highl inclined wells
3. ractical pro!lems. #weeps
6 Cuttings transport
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"M
6. Cuttings transport 6.3. Highl inclined wells
3. ractical pro!lems. #teera!el motors
6 Cuttings transport
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Comparison of pick-
up weig! an" s#ack-
off weig! ("rag
resis!ance)
$erformfre%ue
n!
wiper!rips
9 MI9 *M
HKL
MD
6. Cuttings transport 6.3. Highl inclined wells
. ractical solutions
6. Cuttings transport
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-he $aster we drill the higher the 4ualit0: 7rill ast: ;igh cuttings transport eicienc
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Ch. 7. &C/
Introduction
& accl!ati%nannula! &!icti%n cuttings su!g s-ab !%tati%n
mud
p p p p p
.)( g/
+ + + + = +
/%7
7e
p
th
7. &C/1 Mud /ensit
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actors
1. /ensit control
=
#
m
2
'2
'
=
add
add
#
#
l0g/2.4=
#m
@arite'
Salt'
1.3*
1.1*
5 tan& o 0 m3contains mud o ?A 1. &g!l, should be reduced
to 1.40 with mud rom a tan& o sea water, 1.02 &g!l.
2.'535.0
'0.060
40.'025.'
50.'40.'60 =
=
=add#
1. Mud /ensit2. nnualr $riction3. Cuttings. *otation o$ drill string+.#urge " #wa!6.-%variation
7. &C/
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1. /ensit control
8arite " salt
7. &C/
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w
8.5 - 2.6 *'0-3 + 2.5 *'0-5p
o .0 - 3.0 *'0-3 + 4.4 *'0-5p
mud (in #B)
7uring normal operations the two eects, p and T, will neutraliCe each other since both increase with depth.
Ahen ma one eect dominate, causing an adDustment"
1. /ensit control
7. &C/
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2. nnular $riction
%uttings increases annular densit b 0.03 &g!l.
Eiscosit and low rate is the same. 7oes SPP react"
&!icti%n
%ut
pump
in
hg
v
g
ph
g
v
g
p +
++=+
++
22
22
7. &C/
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%cu!!ings
hmROPdbit
/00026.0)60*60/('2*32.044 22
==
ccu!!ings,o
%cu!!ings
/ (%pump
%cu!!ings
) %cu!!ings / %pump
R! !ranspor! / ann (ann6s#ip)/ ann '6s#ip/ ann 0.5
cuttings= 19 ccuttings,average ' 5 * 0.' 0.5
s#ip
"p
2*g (p-
mu") / 6
eff* f
cu!!ings 0.5 m/s
ccu!!ings,aerage
ccu!!ings from !e orion!a# sec!ion
/ R! 0.'2 0.05 0.025
mu",aerage 1mu" ('- ccu!!ings, aerage ) 1cu!!ingsFccu!!ings,aerage
'200 ('-0.'2) 2500 * 0.04 ' 356 kg/#
'.'2
'.''.'2
'.'
s#ip
0 s#ip
0.5
.ann
)'m/s
0.000
0.020
0.012
0.00022 m3!s
3. &$$ect o$ cuttings. &li$ied
7. &C/
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3
2
'0 &&
v!
! ! ! !
=
r= 9(dv!dr - dvr!dr)
. *otation o$ drill pipe. &empli$ied
#
4
#ieldobse
rvation
Theoret
ical
7. &C/
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a!a&l%-
displacdv%lum%&!atpip pip
annulus
v "
"
surge
248
h$d!d
v
d'
dp =
ue !o c#inging, surgean" & is no! s!raig! forwar"
'. na#!ic approac for #aminar f#ow regime, inc#u"ing c#inging
2. !an"ar" "rau#ic fric!ion mo"e#s
3. "ance" approac, inc#u"ing e#as!ici! of f#ui" an" s!ee# pipe
arc - eiss7ack
rooks ('80, $9 '0 863)
+. #urge and swa!
7. &C/
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#tep 1. 9nderstand the underling phsical sstem. #tart with the simplestsstem ! reducing the compleit: appl simpli$ing assumptions
#tep 2. #;etch the sstem and draw an envelope with ingoing and eiting $orces#tep 3. #olution
#tep . Improve the model
Gnitial understanding o surge!swab pressure'
:5ssume stead9state low
:Heometr deined b #igure
#tep 10
#impli$ications0:%oncentric inner pipe:Smooth clinders deine annular wall and pipe wall
:%losed end pipe ! loat valve. pinside 7P= pann:5ssume clinging actor =0. (the clinging volume ehibits 10 9 40 I o the downward lowing volume,
depending on the relative slot siCe):Stead9state process. o luid acceleration:nl ewtonian and Power law luids:Gnelastic luid and drill string
+. #urge and swa!
7. &C/
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#tep 1. -he phsics % simpli$icaitons (continued)
Commen!s on elastic materials
o! pipe e#as!ici! an" f#ui" iscous force are par!icipa!ingin "e!ermining pipe "isp#acemen! "uring !ripping, as we## as
forma!ion an" cemen! e#as!ici!. +e a## inf#uence !e
pressure surge.
+e figure comparers a surge si!ua!ion were iner!ia
effec!s are presen!. nega!ie 7o!!om pressure surge is
of!en o7sere" a! !e surface wen !e "ownwar"
moemen! of !e "ri## s!ring is 7roug! !o res!, a wa!erammer affec!
+. #urge and swa!
7. &C/
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#orces involved'
dp Acrosssection = Ashear
#tep 2. #;etch and draw and envelope o$incoming and eiting $orces $orces)
#orces in and out across the
envelope'
dp r2 = 2rdl
dp r = 2dl
Gntegrating aiall
p/(2L r =
+. #urge and swa!
7. &C/
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#tep 3. #olution
+. #urge and swa!
#or laminar low it is oten possible to ma&e a purel anltical solution. #or more cople precesses it ma become necessar with': #inite elements: ther numerical methods: /mpirical solutions
@ac& to our simpler process. @eore integrating over the envelope the variables need to be dierentiated'
to d, r to drGntegrate now rom r = $0, where t = 0
to r = r (an r)
p ! (2
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+. #urge and swa! #tep 3. #olution
7. &C/
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+. #urge and swa! #tep 3. #olution (continued)
7. &C/
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&4uivalent Clinging Constant0
%ontribution o pipe velocit towards pressure drop. The clinging constant ma beepressed as'
Jc= cling! tot
To ind clingit now remains to integrate rom r = $7Sto r = rcling
r = $clingwhen v = 0
The be determined
+. #urge and swa!
#tep 3. #olution(continued)
S. S.
7. &C/
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Acceleration of drill string
Gelling of mud in drill string and annulus
Hoisting of drill string with gelled mud inside
Starting mud pump with gelled mud in drill string and annulus
,
,
pip &&
accll!ai%n pip
ann &&
"p ma a
" = =
4 -gl
pip
p
O
=
pip
-
1(
+hg
=
4
:se ge# s!reng! measure" af!er '0 min or e%uia#en!.Can 7e 7roken 7 ro!a!ing /reciproca!ing !e "ri## s!ring
reaks on# oer a cer!ain #imi!e" "is!ance "ue !o
compressi7i#i! of wa!er / "eforma!ion.
#tep . (more realistic assumptions)
+. #urge and swa!
7. &C/
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#urrounding
temperaturein ocean and$ormation
Conduction
Convection
-emperature variation
/ata and model
7. &C/
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( )'2/#n2
RR
2/0q
=
( )%%- 22"hq = 364.4==0
hd3u
!
2
!
02cu
/2c
tpp
=
( )
!
titi
!
!!
titi5!!
t
titi!!
p
p
+
+
=+
),,(),',(2
),,(),,'(2
),,()',,(2
1. &stimate umerical solution
iteration counter = &
E = 2rrC
-emperature variation
Model
Ch. . !ellbore stabilit" 1. Introduction2 Mechanical sta!ilit t t
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Ceneer! ('6, ;C$+), an
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2. Mechanical sta!ilitA pure
Stress related instabilit'
%reep' Aellbores that stas open or a long time
(wee&s), tend to close in
Tensile ailure at high ?A' #ractures are generated, and detected at the
surace as lost circulation.%ompression ailure at low ?A' %avings, brea&outs,
eventuall leading to total wellbore collapse
icture
Beometr0
Cause0
Counter%
measure0
98/ 8/ re%eisting wea;nesses
Increase M? ptimiDe traEector Improve $luid loss
Monitor &C/ /ecrease M? *educe hdraulic , mechanical attac; Monitor &C/
= #!5
= l!l
$re-e>is!ing weakness in !e forma!ion, enancing !esi#e / copmpressiona# fai#ures
?au#!s crossing !e we##7ore / na!ura## s!resse"
@n!er-7e""e" forma!ions (7e!ween #i!o#og canges, 7e""ing ang#e c#ose !o we##7ore ang#e) Aa!ura## weak forma!ions (coa# 7e"s, cong#omera!es, #oose san"s, e!c)
Surveillence
at the surface
@. ?ell!ore sta!ilit 2. Mechanical sta!ilitA com!ined with chemical
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+ere are !ree mecancica# s!resses
'.@n-si!u er!ica# (oer7ur"en) an" resu#!ing orion!a# s!resses
2.$ore pressure3.?orces ac!ing a! in!ergranu#ar con!ac! or a! cemen!a!ion poin!sB coesie force
sing#e se! of c#a p#a!e#e!s connec!e" !o a pore
=ecanica# forces inc#u"e ',3,ppore cemen!a!ion
@. ?ell!ore sta!ilita. -ransport mechanism
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+ere are !ree cemica# forces in genera#
:an "er aa# forces
:9#ec!ros!a!ic repu#sie forces (orne):?orces (repu#sie / a!!ac!ie) resu#!ing from "ra!ion / so#a!ion of c#a surfaces from
ions presen! in in!er#aer spacing (a"sor7e" or free)
a!!er !wo forces are usua## #umpe" !oge!er !o form !e "ra!ion or swe##ing pressure
a. %ransport mechanisms
+e four mos! usefu# e%ua!ionsD
'.?#ow of wa!er "rien 7 "rau#ic pressureD "E/"! k/f."p/"r
2.$ressure "iffusion aea" of !e wa!er fron!D "p/"! k/(f.Feff) G "
2p/"r2 '/r ."p/"rH. Feff F '/#* (fm grain(F))
3. iffusion (?ickIs #aw)D "c/"! G "2c/"r2 '/r ."c/"r. iffusion of ions moes in !e opposi!e "irec!ion of wa!er f#ow
Type of ow dp/dl D(chem.pot)/dl
Water Convection (direct
transmission)
Osmosis
Solution /
ions
Advection (indirect
transmission)
Difusion (Fick)
@n a""i!ion comes !e Capi##ar pressureD
4.
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:ri##ing a! ig "rau#ic oer7a#ance:ri##ing f#ui" ion c J pore f#ui" ion c
iffusion of ions wi## !ake p#ace. ssume no coup#e" f#ow
:Kow wi## !e 3 processes (wa!er con!en!, prore p an" swe##ing p) #ook #ike af!er some !imeL
$ressure pene!ra!ion an" ion "iffusion in sa#e, o7!aine" 7 app#ing e>pan"e" so#u!ion of !e !ree !ranspor! e%ua!ions an" ma!eria# cons!an!s
for !pica# sa#e (ksa#e '0-2' m2). Moering e%ua!ions pre"ic!s !e "ee#opmen! of !ree fron!s aroun" a we##7ore in a sa#e s. !ime
a. -ransport mechanism
mm
cm
dm
= mudvap%!
s-llp
p
#
R2p
,#n
@. ?ell!ore sta!ilit 3. Chemical activit
! # lli $ h l
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efD @ni7i!ion
re"uc!ion of
swe##ing pressure
NC# minimies swe##ing "ue !o sma## "egree of "ra!ion of
N. u! i! is more comp#e>D ! ig c, swe##ing increases again
N
rep#aces #ess ini7i!ie ions. #so anions in!ro"uce" in !e in!erp#a!a#spacing. oes no! occur in !e fie#" (Nneer occur a! suc ig c a#one)
+is effec! !akes p#ace s#ow# ("iffusion is s#ow). pswe##can neer reac ero.
Koweer, swe##ing (e>pansion) can 7e ero "ue !o cemen!a!ion 7on"s
u! a#so c#a !pe "epen"en!D N"oes no! ini7i! @##i!es, an" ma increase
swe##ing of Nao#ini!es
we##ing is comp#e> an" osmo!ic swe##ing is a !oo
simp#is!ic mo"e#
we##ing pressure in Aa-=on!mori##oni!e as a
func!ion of in!erp#a!e#e! "is!ance. !a7#e s!a!es are
in"ica!e" 7 arrows. ensi! "is!ri7u!ion of wa!er-
o>gens are a func!ion of !e "is!ance. ?rom !e
see! surface. Resu#!s are snown for !e s!ag7#e
s!a!es of 4 "ifferen! spacings
we##ing !es!s of sa#e con!aining 65 O mon!mori##oni!e. +e swe##ing
in"e> "oes no! go !o ero, i.e. !ere is a#was resi"ua# swe##ing
p%!-at!vap%!p# , !. #welling o$ shale
@. ?ell!ore sta!ilit
Implications o$ chemical activit and countermeasures
1. ?ell!ore sta!ilit2. Cuttings sta!ilit
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@ni7i!ors canno! preen! pore pressure increase in"uce" sa#e pro7#ems 7ecause ini7i!or "iffusion fron! #ags 7ein".
ome!ing more !an ini7i!ion is nee"e". +e answer isD $reen! wa!er f#ow !o supress pressure pene!ra!ion. +is is ow
!o aciee i!D
'. pp# ra"ia# suppor! !roug proper = (prere%uisi!e)
2. =ain!ain suppor! 7 re"ucing fi#!ar!e inasion (see #a!er)
3. :se ini7i!ie mu" (see #a!er)
: Swelling pressure
: H"draulic pressure
we##ing pressure canno! 7e re"uce" "own !o ero. n effec!ie !esi#e force is remaining. en ne! !ensi#e forces oercome sa#eIs
!ensise s!reng! (#ow in sa#e), ie#"ing a! wakes! si!es wi## !rigger su7se%uen! fu##-sca#e fai#ure. $ressure f#uc!ua!ions (from &) wi##
cange "rau#ic suppor!, an" ma "e#ier !e Pfina# 7#owQ !o a#!rea" weakene" sa#e.
+is !ime-#ag in !ranspor! is regar"e" as !e main reson 7ein" ini7i!ors sor!comings as sa#e-s!a7i#iers. en arriing , ini7i!ors
arrie !oge!er wi! wa!er !e ma #ea" !o er sma## !o #ow p swe##(as oppose" !o #arge pswe##if no ini7i!or was presen!).
a!er we wi## ceck !ree "ifferen! mu" !pes !o see ow !is can 7e aciece" prac!ica##
. Implications o$ chemical activit and countermeasures 2. Cuttings sta!ilit3. 8it !alling. #urveillence o$ sta!ilt
1. ?ell!ore sta!ilit
@. ?ell!ore sta!ilit . Implications o$ chemical activit and countermeasures
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Cu!!ings e>pose" !o !e same mecnisms as !e we##7ore, e>cep! !a!
:Meome!r an" s!ress con"i!ion are "ifferen!:+iming is "ifferen!. 9>posure is !pica## on# ' our
@n-si!u s!resses are su""en# re#iee" an" rep#ace" p"rwen cu!!ings are genera!e"
r p"r ppore- pswe##
an" wi## 7e in !ension if p"r ppore pswe## an" "isin!egra!e if pcoesionis oercome
+e fo##owing wi## !ake p#aceD
'.p"rwi## #ea" !o s#ow inasion an" e%ua#ie ppore, 7u! norma## no! in on# '
2. 7igger pro7#em is p"rrecuc!ion as cu!!ings are !ranspor!e" up !e we##7ore, com7ine" wi! s#ow
pswe##increase, pro7a7# !e mos! "e!rimen!a# effec!
Countermeasures&
'.9ncapsu#a!ion
2.u! off wa!er 7 enancing iscosi! of fi#!ra!e
3.:se ini7i!ie mu" (see #a!er)
2. Cuttings sta!ilit
@. ?ell!ore sta!ilit . Implications o$ chemical activit and countermeasures
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!ress re#ease on cu!!ings ma !rigger "ra!ion. pswe##ac!s #ike an Pun#oa"ing springQ in nee" of wa!er.
Cu!!ings are in con!ac! wi! !e 7i! s!ee#.
'.rawing wa!er inwar" ma acuum !emsees on!o !e 7i! an" !o eac o!er.
2.isin!egra!e" par!ic#es / swe##e" par!ic#es ae an enourmous surface area. +e sma## "is!ance !o !e s!ee# surface /
o!er ca# par!ic#es awokes an "er aa# forces, o#"ing !e par!ic#es on!o !e 7i! surface (c#ogging / s!icking). +e
c#ogging is c#ose# re#a!e" !o p#as!ici!.
CountermeasureD
'.Neep !e cu!!ings ou!si"e !e p#as!ic / swe##ing one
2.@ncrease "ispersii! in !e f#ui" (pK J 8)
3.=ake !e sufaces oi#-we! (see #a!er)
3. 8it !alling
S"mptoms(a#was #ook for "eia!ion from norma#)
@. ?ell!ore sta!ilit . Implications o$ chemical activit and countermeasures
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S"mptoms of Mobile fm
:e##7ore erosion wen "ri##ing !roug !e sa#! forma!ion an" / or !oug sa#e a7oe or 7e#ow !e
sa#! forma!ionS 9>cessie !or%ue an" pack
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"p + g w -
%"pe 0& 1on2invading !)M , /)M +balanced Aw-
%"pe #& KCl , 3H3A
Re"uces pswe## in smec!i!ic c#a - oung reac!ie gum7o !pe sa#e.
NC# e>i7i! !e iges! inii!ie effec! of a## sa#!s.
Ca!ions e>cange p#ace wi! Aaions. u! ae some sor!comingsD
'.Ao fi#!ra!e preen!ion
2.
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Canges are sown re#a!ie !o !e
proper!ies in !e na!ie sa#e an" !o non-
in7i7i!ie =. +e figure sows !a!
pore pressure wi## 7e enance" in a##
!ree inasion ones, 7u! !e wa!er
con!en! an" swe##ing pressure is re"uce"
Koweer, 7o! ingre"ienses (NC#
$K$) fa## sor! wen o#"er, #ess
reac!ie sa#es are "ri##e".
%"pe #& KCl , 3H3A +continued-
$o#mers, #ike $K$, wi! func!iona#
groups of posi!ie po#ari! a7sor7s on!o
c#a surfaces a! mu#!ip#e si!es!e
are more "ifficu#! !o e>cange/remoe.
Moo" ini7i!ors wen #ow-mo#ecu#ar (
'0 000)B pene!ra!e pores of !e sa#es.
Kig mo#ecu#ar po#mers, #ike $K$,
#a!ces on !o !e ou!er surface of sa#e
in a we7-#ike pa!!ern an" com7a!
"isi!egra!ion of sa#e. $ore 7#ocking is
minima#. @"ea# a""i!ie for cu!!ings
s!a7i#ia!ion.
CaC#2, Car2are ig# so#u7#eig "ensi!. +eir a"- an" "isan!ages areD
@. ?ell!ore sta!ilit @.+. Inhi!itive muds
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Resu#!ing mu" !pe 7eaior is sown ere. e see !a! !e wa!er
con!en! an" !e pore pressure are e>pec!e" !o 7e re"uce". u!
swe##ing pressure is e#ewa!e" in !e fi!ra!e- an" !e @ -one "ue !o
unfaora7#e e>cange of ca!ions (Aa).
$o#-g#cero# an" g#co#s are
saccari"es of #ow mo#ecu#ar sie (
'0 000). +e iscosif !e fi#!ra!e /
7ui#" an in!erna# fi#!er an" re!ar"
fi#!ra!e inasion.
%"pe & /smotic !)M4 CaCl5 meth"l2glucose
2 2
:Kig osmo!ic pressure (7u! "ue !o #ow mem7rane efficienc (' '0 O) !e osmo!ic pressure is
#mi!e" !o '/'0 '/'00), can 7e app#ie" !o par!ia## offse! !e "rau#ic oer7a#ance:Kig fi#!ra!e iscosi!-eak mem7raneion "iffusion in!o sa#e, agains! !e 7ack-f#owing
wa!erAae>cange Npswe##wi## again increase
@. ?ell!ore sta!ilit @.+. Inhi!itive muds
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w
cla$-p
,
das
1.''.'
'. Co##ec! c#a from upper ;ura. r an" crus
2. =easure s. w3. =ake a p#o!
4. C#o##ec! presere" c#a. =easureorigina# 2.'35. ?in" origina# wfrom p#o!
%"pe & /smotic !)M +continued-
=
p%!-at!vap%!
mudvap%!
s-llp
p
#
R2p
,
,#nKere is a me!o" of ow !o "e!ermine w, pore. e wi## use i! !o "e!ermine pswe##.
2.'3
@. ?ell!ore sta!ilit @.+. Inhi!itive muds
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8hal -ith%ut -tting agnt 8hal -ith -tting agnt
'. ase oi#D !e con!inuous pase
2. 9mu#sifierD emu#sif wa!er in oi#
3. e!!ing agen!D makes !e we##7ore oi# we!
4. a!erD forms iscosifing "rop#e!s
%"pe 0& 1on invading !)M , /)M
!ater activit"&
wis more impor!an! !an
se#ec!ing 7e!ween !ure 7e!ween !wo unmi>a7#e #i%ui"s (oi# an" wa!er)
!ettabilit"& o#i"s can 7e wa!er or oi# we!
( 0 40 w I)20
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%"pe 0& 1on invading !)M , /)M +continued-
)alanced water activit"&
wi## #ea" !o no cange in !e sa#e
Lower water activit"&wi## #ea" !o osmo!ic f#ow of wa!er from !e sa#e pores !o !e mu"
(in"us!r s!an"ar" of "ri##ing !rou7#e free sa#e (2000)
!ep 'D Reiew re#ean! offse! we##s!ep 2D na#e forma!ion proper!ies
!ep 3D e##7ore s!a7i#i! mo"e#
@. ?ell!ore sta!ilit
6. /rilling limit
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!ep 3D e##7ore s!a7i#i! mo"e#
!ep 4D Ko#e c#eaning, wa7, 9C
!ep 5D ummar
200'D :se 7es!-in-c#ass !ecno#og !o e#imina!e / minimie A$+ make a perfec! o#e
Step #& *ind /ffset wells +e7amplified b" trouble well -
T?7 (t) Gncl. (0)
1+,830 3 7rill to 1+830M' una!le to slideGpoor M?/ signal. @uilding angle N 0.4O ! 100M 8allooning 1@73' Q
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Step & *ormation properties , data collection
@"en!ifica!ion of opera!iona#
pro7#ems s. fm
ources an" !ransfer of e>perience "uringcase 7ui#"ingD Rea#-!ime "a!a (#ef!) an"
ocumen!s (#ower rig!). n e>per! is
nee"e" !o crea!e" e>perience cases for #a!er
re-use "uring p#anning of simi#ar we##s
@. ?ell!ore sta!ilit 6. /rilling limit
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Step & *ormation properties ,data collection
$o!en!ia# errors wic
can #ea" !o fai#ures
$o!en!ia# fai#ures
?ai#ure "efini!ionD n een! causing A$+
@. ?ell!ore sta!ilit 6. /rilling limit
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Step 0& !ellborestabilit"
owno#e pressure
response as surface
rea"ings "uring
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Step 8. 6CD
Aee" !ree mo"e#sD
:9C:wa7 & urge:Cu!!ings !ranspor!
Kere is a one-page o#e-c#eaning
summar for an 9R-we## (ear 2000)
?#ui" #oss in
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Step 9. Summar"
:se #a!es! aai#a7#e !ecni%ues a!
a## !ime. Neep ourse#f up"a!e"D
:ccura!e simu#a!ors / mo"e#s,
inc#u"ing mos! rea#is!ic
assup!ions:@n!egra!e a## mo"e#s an"
assump!ions if possi7#e
"as per '000 f!) agains! a !ecnica# #imi! of '.' "as wi!ou! an o#e pro7#ems. +e we##
was "ri##e" a#mos! !wice as fas! as !e ' goa# (3. "as per '000 f!).
+e mos! impor!an! person "uring p#anning
is !e e## engineers. u! impor!an!
suppor!ers "uring p#anning are
Meo#ogis!s,
$e!ropsicis!s,
Rock mecanicc
=u" engineers
Some final integrated issues&
i## 9C cross !e pressure win"owL Cange we##pa! or s!reng!en fm, cange reo#og, cange mu" !pe (=)
eepage #osses !o me"ium #osses e>pec!e"L = as a 7e!!er frac!ure ea#ing a7i#i! "ue !o swe##ing of c#a
Kig +&L "" #u7rici!
eep we##L ue !o compressi7i#i! "owno#e = V surfaceW
ong open o#e !imeL Kiger = is necessar !o main!ain s!a7i#i! ("ue !o s#ow# c#im7ing ppore)
Aear 7 we##L @ncrease frac!ure propaga!ion resis!anceC= nee"e"L aoi" increase" reo#ogWW
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Step 9. Summar"
#ummar
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#ummar
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A@