Download - Mud Loss Course Powerpoint-RJY-11 Feb 2013
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
1/372
Ch-1:INTRODUCTION
TO
MUDLOSS
1
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
2/372
What is Lost Circulation
Loss of drilling fluid to formation during drilling
Loss of cement slurry to formation during
cementing operations
Loss can be Gradual lowering of pits
Complete loss of returns
What is not Lost Circulation
Filtration loss
Filling of new hole by mud drilled at faster ROP
2
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
3/372
Classification of Mud Loss
i!ided into three categories"
#eepage losses
Partial losses
#e!ere or total losses
$
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
4/372
Seepage Losses
Rate of mud loss" %p to 1& barrels' hour for oil base mud
%p to 2( barrels 'hr for water base mud
#ometimes it may be ignored if mud loss also
ta)ing place with dumped cuttings from sha)ers
#tarts at !ery slow rate similar to filtration loss in
highly permeable formations
*
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
5/372
+o find out whether mud loss is from surfacee,uipment or down hole #top drilling and pull the bit off-bottom.
#top all mi/ing 0 non-essential solid remo!al
,uipment Obser!e well for seepage losses with and without
circulation
Seepage Losses (Contd!
(
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
6/372
D"illing too fast
When high drilling rates are attained e!en in hole
sies as small as 3.(45 suspected seepage loss canactually be attributed to other factors.
One such factor is normal displacement of drilled
solids with fluids. For e/ample5 while drilling (& feet per hour in
3.(4 hole5 $.( bbls 67&.8& cu m9 of drilling fluid per hour
will be re,uired to fill the new hole drilled.
:n 12-1'*4 hole5 ;.$ bbls 67 1.2& cu m9 of drilling fluid per
hour will be re,uired to fill the new hole drilled.
8
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
7/372
D"illing too fast
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
8/372
ecision to be made whether to drill ahead or
cure this first
:f formation damage and stuc) pipe primary
concern5 then cure this loss first.
:n e/ploratory area5 loss to be controlled beforedrilling ahead
#eepage loss in deeper pay one formations
also to be controlled =ay become partial' total loss if ignored for too
long
Seepage Losses (Contd!
3
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
9/372
#a"tial Losses
Rate of mud loss" 1& to $& barrels' hour for oil base mud
2(-1&& bbls' hr for water base mud
:t may force to stop drilling ahead and tac)lethis mud loss problem first
:f drilling fluid can be made a!ailable and well
pr are within operating limits5 may drill ahead
with these losses.
>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
10/372
Se$e"e o" Total Losses
Rate of mud loss ? 1&& barrels' hour
Regaining full circulation is main priority
Reducing mud weight may be one of the
options for loss control but well has to be
monitored all the times for any influ/ in the wellbore
:f drilling fluid can be made a!ailable and well pr
are within operating limits5 may drill ahead withthese losses.
1%
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
11/372
M&C'NISMS)
CUS&S
ND
#ROS#&CTI*&MUD
LOSS+ON&S
11
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
12/372
Mud Loss Mechanis,s
+here are two mud loss mechanisms"
@atural losses
:nduced losses
12
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
13/372
Natu"al Losses
+a)e place in %nconsolidated formations in top hole
Aighly permeable shallow sands
@aturally fractured formations Ca!ernous or !ugular limestones
1$
U lid t d ti
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
14/372
Unconsolidated o",ations
Generally at shallow depths
in surface hole
@ormally consist of sand or
loose gra!els
Pores usually too large for
formation of a competent filterca)e.
Bery high permeability of 1&
-1&& m arcies in coarseunconsolidated formations.
nough for whole mud to be
lost 1*
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
15/372
Unconsolidated o",ations (Contd!
Lost circulation may start while drilling5 tripping or
circulating mud prior to running casing. Loss usually starts with a gradual reduction in pit
le!el
Later on5 rate of loss may become more than ma/mud pumps discharge capacity if no remedial
action ta)en.
Loss can range from seepage to se!ere losses
and may sometimes lead to stuc) pipe.
1(
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
16/372
Unconsolidated o",ations (Contd!
:mportant to pre!ent shallow losses as washingout of unconsolidated formations may form a
large ca!ity around the rig
+his is less stable and could ca!e-in from the
o!erburden.
18
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
17/372
'ighl. #e",ea/le o",ations
=ainly depleted reser!oirs
Can occur at any depth. epletion due to producing
oil from formations in the
same field or nearby fields. Aigh permeability allows
entry of whole drilling fluid
into roc)s.
1;
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
18/372
'ighl. #e",ea/le o",ations(contd!
Loss can be from seepage to se!ere depending
on porosity and permeability of formations
Can often lead to differential stic)ing pipe.
=ay cause formation damage
13
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
19/372
Natu"al "actu"es
Loss occurs mainly in formations with natural
fractures or fissures.
Only thing re,uired by fractures is mud
hydrostatic pr to e/ceed the pore pr in the roc).
Can happen at o!erbalances as low as (& psi. :nitial loss can be seepage but li)ely to become
se!ere with passage of time if drilling continues.
+his type of loss difficult to cure as it may not belocalied but may be in large geological area.
1>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
20/372
Natu"al "actu"es
2&
"actu"es in co"e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
21/372
Fracture Porosity
01
N t l t (C td !
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
22/372
Natu"al "actu"es (Contd!
Older5 harder and consolidated formations li)ely
locations for natural fractures. Created by geological mo!ements underground
Aigher fre,uency of occurrence near faults and
areas that ha!e been subected to tectonic forces . +his type of loss can cause some of the most
troublesome lost-circulation incidents.
22
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
23/372
Ca$e"nous O" *ugula" o",ations
%sually in low pr carbonate 6limestone and
dolomite9 or coral reefs. :n limestone5 !ugs created by continuous flow of
water for !ery long time dissol!ing part of theroc) matri/ 6leaching9
+hus created !oid spaces often later filled withfluid.
When these formations are drilled5 drill string
may freely fall thru !oid ones accompanied withsudden loss of returns
2$
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
24/372
2*
*ugs in co"e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
25/372
Vugular Porosity
0
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
26/372
Ca$e"nous O" *ugula" o",ations (Contd!
Loss rate often e/ceeds ma/ mud pumpdischarge capacities.
Ca!erns can be localied or part of a more
e/tensi!e system Boids may range in sie from pinholes to tunnels.
Ca!erns are most difficult lost-circulation ones to
re-establish returns
28
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
27/372
Ca$e"nous O" *ugula" o",ations (Contd!
:n many cases the well must be drilled Dblind45 i.e.5with no returns.
:f ca!erns are close to surface5 location collapse is
possible. Bolume of mud loss will depend on degree to
which !ugs are interconnected.
:n areas with a drilling history5 these losses areusually predictable.
2;
NATURALLY OCCURING LOSS ZONES
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
28/372
NATURALLY OCCURING LOSS ZONES
I d d L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
29/372
Induced Losses
:nduced losses can happen in allformations.
+hese fractures occur when sum of
all e/erted pr on roc)s e/ceeds
fracture gradient of roc)5 causingformation to brea) down.
Once a fracture created or opened
by an imposed pressure5 difficult toheal and formation may ne!er
regain original strength.2>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
30/372
Induced Losses (contd!
Fracture propagation pr is always less than
fracture initiating pr. :t has been obser!ed that induced losses
account for maority of all the recorded lost-circulation incidents.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
31/372
Induced Losses:
Ci"culation Rate 2 &CD
Flow properties and circulation rate used should
de!elop minimum pr losses consistent with efficient
cuttings remo!al to a!oid pipe stic)ing and annulus
loading. /cessi!e circulation rate 0 fluid rheological
properties may e/pose formation to high pr 0
,ui!alent Circulating ensity 6C9.
$1
Induced Losses:
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
32/372
Induced Losses:
Ci"culation Rate 2 &CD (contd!
:nsufficient circulation rate results in drilledsolids being loaded in mud causing high C.
+his increase in C may be sufficient to
induce losses.
$2
Induced Losses: &CD
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
33/372
Induced Losses: &CD
C calculated by following e,uation"
C 6ppg9 HI 6ppg9J K HPa 6psi9' 6o.&(2+B 6ft99JM
Where
I =ud weight in lb'galPa pressure loss in annulus in psi
/ample"
:f I 1& ppg5 Pa (& psi5 +B 1&5&&&N
+hen C H1&J K H(&' 6&.&(21&&&&9JM
1& K &.1 1&.1 ppg$$
Induced Losses: 'igh #u,p #"
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
34/372
g p
:f circulation after round trip started at normal
#P= may cause induced losses due tode!elopment of !ery high circulating pr
Pump pr surging also caused by increasingpump #P= too rapidly after pipe connections
+his condition occurs when drilling at deeperdepths.
Eecomes critical when present mud gradient isapproaching fracture gradient.
$*
Induced Losses : 'igh #u,p #"essu"e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
35/372
Induced Losses : 'igh #u,p #"essu"e
6Contd.9
/perienced in some wells in =umbai Aigh Pump pr. shoots to 12( )g'cm2e!en at 1&-1( #P=
when circulation resumed after round trip.
#lowly pr comes down and #P= can be increased
thereafter to normal #P=. +a)es time before we see returns due to less #P=
Aighly gelled mud on sha)ers at bottoms up.
$(
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
36/372
Induced Losses: Su"ge #"essu"e
Lowering string too fast on connections cande!elop high surge pr
+ripping in string too fast can also de!elop
high surge pr. Running in casing creates piston effect and a
surge pressure.
+his can cause induced fractures
$8
Induced Losses: Su"ge #"essu"e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
37/372
(Contd!
+his problem made worse by Erea) circulation not carried out at regular inter!als
during R:A drill string in deeper holes with long
open hole sections
Pac)ed-hole assemblies
When drilling fluid has high gel strengths.
$;
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
38/372
Induced Losses: Su"ge #" (Contd!
Erea)ing circulation5 rapid lowering of drillstring or casing can cause high pr pea) thatcan brea) down formation.
+hen induced fracture propagates rapidly atfracture propagation pr causing losses.
Fracture propagation pr is significantly lowerthan formation brea)down pr.
$3
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
39/372
Induced Losses: &3cessi$e RO#
=ay result in huge amount of cuttingaccumulation in annulus when drilling in softformation in larger sie holes as mud may notbe able to lift drilled cuttings entirely.
Results in high C When formation with a low-fracture gradient
e/posed in OA section5 may lead to mud loss.
$>
Induced Losses:
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
40/372
Sloughing o" Ca$ing Shales
:ncrease drilled solids in annulus5 causing !ery highC.
=ay also result in hole pac) off.
When annulus is restricted5 pump pr starts rising.
:f #P= not reduced5 high circulating pr whentransmitted to formation may cause fractures.
!en temporary pac) off can cause high pr
*&
I d d L 4 h t
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
41/372
Induced Losses: 4ashouts
Aole washout leads to drop in mud !elocity inwashed out well bore section.
#o cuttings accumulate in washed hole section.
Cuttings also accumulate in larger sie rat hole
caused by casing short landing.
*1
I d d L 4 h t ( td !
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
42/372
Induced Losses: 4ashouts (contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
43/372
Induced Losses: Mud 4eight
=inimum safe mud weight re,uired to "
Aold bac) formation pr
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
44/372
Induced Losses: Mud 4eight (contd!
While drilling5 transition from an abnormallypressured one to a normal or sub-pressured
one may be encountered. /ample"
Ro)hia-1
Aigher mud weight will cause induced loss in
lower depleted or sub-normal ones
**
Induced Losses: Mud 4eight (contd !
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
45/372
Induced Losses: Mud 4eight (contd!
+hese induced losses occur by hydraulically
fracturing of formations. Pr may be sufficient to cause whole mud loss
into permeable sandstone.
:f hydraulically fracturing of formationsuspected5 most probable point of loss is ust
below casing shoe.
*(
Induced Losses: 4ell Cont"ol
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
46/372
Induced Losses: 4ell Cont"ol
uring well control situations5 loss can occur when
the well is shut-in. #hut-in pr transmitted down the well bore may
brea) the formation at its wea)est point.
:f well remains closed on gas )ic) withoutcirculating it out5 !ery high pr will be e/erted on well
bore.
+his not only results in lost circulation5 but losing
control of well.
*8
Induced Losses: 4ell Cont"ol
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
47/372
*;
Induced Losses: 4ell Cont"ol (contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
48/372
( !
:f influ/ !olume is more5 shut-in pressures morewill be more
#o surface pressure e/erted on well bore will bemore.
:f proper procedures are not followed5 an
underground blowout can occur.
*3
Induced Losses:
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
49/372
Inefficient 'ole Cleaning
Cuttings affects lost circ in se!eral ways. When hole cleaning inade,uate5 cuttings
accumulate in annulus5 loading up drilling fluid until
losses are induced.
:n de!iated wells5 cutting beds are not properly
eroded.
*>
Induced Losses:
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
50/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
51/372
Conse5uences of Mud Loss du"ing
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
52/372
D"illing IMM&DIT& CONS&6U&NC&S:
Aole instability
Lost time
Loss of mud
LON7 T&RM CONS&6U&NC&S: Reduced safety
Well )ic)s
%nable to reach +
#tuc) pipe
Poor cement ob(2
Conse5uences of Mud Loss du"ing
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
53/372
D"illing +he loss of hydrostatic head that may result in a well-
control situation. +he reduction in the pr gradient may lead to wellbore
instability5 which could result in hole collapse and'or
stuc) pipe.
#ide trac)s or complete loss of the well.
Failure to achie!e ade,uate annular cement
co!erage.
Good ,uality formation e!aluation may not bepossible.
($
Conse5uences of Mud Loss du"ing
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
54/372
#"i,a". Ce,enting
Reduced safety
Gas migration
Reduced annular co!erage
Poor one isolation
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
55/372
Mu,/ai 'igh
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
56/372
Locating the loss one position is paramount
to rectifying lost-circulation problems. Correct
identification of the position of the theft one
allows for proper placement of the lost-circulation
material.
+he theft one can be located from pre!iousdrilling records5 drilling rates5 drilling brea)s5
formation changes and from !arious logging
techni,ues.
(8
#OSITION O LOSS +ON&
:f th l i d hil d illi l
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
57/372
:f the losses are e/perienced while drilling5 loss
one li)ely is on-bottom and caused by natural
fractures5 ca!erns or highly permeableformations.
:f losses are e/perienced while tripping or while
increasing mud weight5 the loss one probablyis not on-bottom and is a result of induced
fractures.
Recogniing a loss while tripping bac) into the
hole re,uires attention to the !olume of fluid
being displaced by the pipe.(;
#OSITION O LOSS +ON&
+hi l b d t i d b ith i l
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
58/372
+his !olume can be determined by either !isual
obser!ation or from regular e/amination of pit le!e
record. rilling into a sub-normally pressured5 naturally
fractured formation usually is indicated by a
sudden high loss of returns accompanied by anincrease in rotary tor,ue. +his is a reliable
indication that the lost circulation one is at bit
depth when no pre!ious problems ha!e been
encountered.
(3
#OSITION O LOSS +ON&
L ll D / tt 8 if
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
59/372
Losses are normally Don-/otto,8 if: +hey first occur while drilling ahead.
+he loss is accompanied by a notable change in ROP5tor,ue5 or drilling roughness.
Q :nduced fractures on-bottom can be caused by a
balled-up EA< or bit restricting the annulus. Q +he loss is due ob!iously to natural fractures5
faults5 ca!erns5 !ugs or high-permeability sands
and gra!els
(>
#OSITION O LOSS +ON&
Losses are normally Doff /otto,8 if:
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
60/372
Q Losses are normally Doff-/otto,8 if: +hey first occur while tripping5 drilling fast or increasing
drilling fluid weight. +hey are ob!iously the result of an induced fracture.
+hey are result of shutting the well in and )illing well.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
61/372
Ch-0:DRILLIN7 #RCTIC&S
TO
#R&*&NT
LOST CIRCULTION
81
Ma9o" Issues
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
62/372
Proper setting depth of intermediate casing
/cessi!e bottom hole' down hole pressures
created during operations.
Correct drilling practices and their
implementation to reduce se!erity 0
conse,uences of loss circulation .
82
Setting Depth of Inte",ediate Casing
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
63/372
g p g
#etting of intermediate casing abo!e transitionone to be a!oided to pre!ent penetration of
wea) formations with higher mud weight.
+he intermediate casing to be landed after
confirming passage into transition one.
8$
&3cessi$e '# (otto, 'ole #"essu"e!;
D'# (Do
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
64/372
D'# (Do
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
65/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
66/372
+hic) mud ca)e.
/cessi!e annulus loading. rilling too fast.
Ealled up EA< 6bottom hole assembly9' down
hole drilling tools. =obile formations
%nder gauged hole
88
'igh Mud 4eight
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
67/372
ach formation has a certain fracture strength. :f hydro static head due to mud column
e/ceeds this strength5 formation may get
fractured.
8;
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
68/372
eep mud weight in the median range betweenpore pressure and fracture pressure.
Run solid control e,uipments regularly to )eep
LG# 6low gra!ity solids9 to minimum le!el.
=onitor mud weight !ery closely.
83
'igh &CD
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
69/372
D ,ui!alent circulating density 6C9 isalways higher than running mud weight due to
resistance to flow of mud across well bore wall
and presence of cuttings in the annulus.4
8>
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
70/372
/cessi!e !iscosity and gel strength to be
a!oided. Formation cutting loading in well annulus to be
restricted.
+hic)ness of filter ca)e to be limited to a!oidreduction of annular clearance.
=ud weight to be optimum and any increase of
=W to be slow 0 gradual.
;&
Cont"ol Measu"es (contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
71/372
Fluid columns in the well bore ' annulus to bebalanced.
Earites sag to be a!oided by controlling mud
rheology .
LG# 6low gra!ity solids9 0 =E+ 6methyl blue
test 9 !alues to be )ept at minimum possible
le!el.
;1
'igh Mud Ci"culating Rate
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
72/372
:t causes increase in C.
Aigh rate of flow across wea) formation
causing hole erosion and mud loss.
;2
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
73/372
%se optimum flow rate for efficient holecleaning.
Birtual hydraulics may be used for this.
;$
Mud #u,p #"essu"e Su"ges
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
74/372
=ud circulation after running in to bottom tobe started at slow circulation rate of mudpump.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
75/372
;(
or stopped suddenly. This is increased by high gel structureof the stationary drilling fluid, which needs to be broken
before it starts to flow. Rotation of the pipe, prior to kicking-in the pumps, can reduce the surge pressure as can areduction of the gel strength of the mud prior to any trips.
S
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
76/372
. p4500
4000
3500
3000
2500
PSI
STATICPOOH-STEADY
SPEED
STATIC
STATIC
RIH-STEADY
SPEEDSTEADY CIRCULATION
SWAB
SURGE
TRIP MARGIN
SHP =3200 psi
ACCELERATE
ACCELERATE
D
ECELERAT
E
DECELERAT
E START
PUMPS
FRACTURE PRESSURE = 5500
pi
FORMATION PRESSURE = 2!00 pi
ANNULUS FRICTION
PRESSURE
=>
Q Pressure Surges when tripping. Run drill pipe and casingbelow critical speeds for running pipe and casing and these
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
77/372
;;
below critical speeds for running pipe and casing and theseshould be used to avoid losses.
Q Rapid pipe movement while circulating or reaming can alsocause surges that can result in losses.
#"actices to $oid #"essu"e Su"ge
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
78/372
+a)e *(-8& seconds to run in and pull out onestand of drill pipe 6!ertical well9.
+his will help to a!oid pressure surges andswabs and pre!ent fatigue failure or sudden
fracture of !ulnerable formations.
;3
Dispe"si/le Mud ; o",ation
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
79/372
ispersible mud ' formation also causes
increase in !iscosity ' mud weight .
+his effecti!ely increases mud wt. ' annular
friction losses.
;>
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
80/372
:ntermediate mud circulation for gel brea)ing.
Periodicity5 duration and depths for circulation
to be decided by drilling crew in consultationwith the mud engineer on case basis.
3&
Contd
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
81/372
Preferably circulate ust before and afterdrilling of dispersible formation.
#uitable non-dispersible mud system may be
used.
31
Thic? Mud Ca?e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
82/372
+hic) mud ca)e can also cause mud loss asclearance between drill string and well bore walldecreases depending upon thic)ness of theca)e.
Fre,uent wiper trips5 preferably once in 2* hrsof continuous drilling to be done in general.
Water loss of drilling fluid should be )ept to aminimum.
32
&3cessi$e nnulus Loading
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
83/372
+his can happen due to insufficient discharge
and improper hole cleaning.
rilling at a !ery fast rate-it is not feasible to
clean the hole with recommended pump ratein general.
+hic) cutting beds Causing Aole pac)-off.
3$
'ole Cleaning Difficult. *s 'ole ngle
4IT' T'& SM& DISC'R7&'OL& CL&NIN7 DIICULT@ T
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
84/372
*RIOUS 'OL& N7L&S
1% A% >%'OL& N7L&
B
'OL&
CL&(NIN7
=%
3*
'ole Cleaning #"o/le,s
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
85/372
o.cott Settling Regions Of Inclination
alled-up '; D"illing Tools
+hi bbi hil POOA 6 lli
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
86/372
+his may cause swabbing while POOA 6pulling
out of hole9 and surges while R:A 6running inhole9.
#wab may cause destabiliation of well bore 0e/posure of wea) formation.
#urge may increase EAP'AP 5 causing
fracture ' loss circulation.
38
Cont"ol Measu"es
%se of proper mud systems to pre!ent
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
87/372
p p y p
dispersion of gumbo li)e clay in the mud.
%se proper discharge to pre!ent re-grinding and
floating of cuttings in the annulus.
%se chemical sweeps to clear ball up from the
EA
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
88/372
=obile formations li)e salt 5 plastic shale andsome coals ha!e a tendency to flow inside the
well bore under o!erburden pressure.
+his results in tight and under gauged hole.
33
Mo/ile o",ations
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
89/372
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
90/372
=a/imum allowable mud weight may help.
Fre,uent wiper trips may help.
%se of suitable mud system may also help.
>&
Unde"-gauged 'ole
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
91/372
Can be caused by undergauged drill bit.
+CR bit run after PC bit run.
=obile formations.
>1
Unde"-gauged 'ole
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
92/372
0
Cont"ol Measu"es
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
93/372
DOn each run a pulled out bit should be gauged
and while lowering new bit reaming should be
done !ery slowly to a!oid hole pac)-off and
mud loss in wea) formations.4
>$
Clea"ing 'ole #ac?-off; "idge
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
94/372
%sing high pump rate to clear bridge' pac) off
not only aggra!ates bridge further 5 it may
also cause formation fracture and mud loss.
+or,ue and slac) drill string with only $&&-(&&
psi pump pressure to regain circulation andincrease pump rate slowly till bridging is
cleared completely.
>*
#u,p Rea,ing Rate
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
95/372
Ream slowly to a!oid pac)-off.
>(
Causes of &3cessi$e '# ; D'#
4hile Casing Lo
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
96/372
g g
Lowering casing too fast.
Bery little clearance between casing and well
bore wall.
Aighly !iscous mud.
:mproper hole cleaning before casing lowering
>8
Cont"ol Measu"es
Birtual hydraulics can be used to simulate
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
97/372
y
surface pressures 0 C while circulatingmud based on annular clearances.
@ecessary adustments to be made to pro!ide
sufficient annular clearances to a!oid high
pressures during mud circulation.
>;
Contd
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
98/372
=ud parameters to be optimied to a!oid
gellation of mud during casing lowering.
:ntermediate circulation as decided between
:C 0 mud chemist may be gi!en.
Aole to be thoroughly cleaned to remo!e
cuttings from the well bore.
>3
Cont"olled D"illing
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
99/372
D:n )nown wea) areas it is a good practice todrill slowly and allow healing time for formation
of protecti!e layer of mud ca)e on the well bore
wall.4
>>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
100/372
ST DRILLIN7
CONTROLL&D DRILLIN7
DRILLIN7 TIM&
4&LL
DT'
1%%
RO#igh R!P can cause annulus loading by the cuttings, which willincrease the "quivalent #irculating $ensity %"#$& and can
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
101/372
1&1
increase the "quivalent #irculating $ensity %"#$& and can
cause losses. Software can be used to monitor the situation andmaintain annular pressures within the required parameters forloss free drilling. Parameters which may be needed toaccompany high R!P are mainly hole cleaning issues but can
also be rheological %increase in viscosity to carry the cuttings ora decrease to increase turbulence&, hydraulic %increase in pumprate& or a combination. Resultant changes to increase R!P canhowever cause losses.
Cont"olled D"illing Techni5ue
rill !ery slowly in the suspected thief one
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
102/372
rill !ery slowly in the suspected thief one.
Obser!e well beha!ior after e!ery S - 1 m of
drilling.
#top and ta)e remedial measure if loss is
encountered.
1&2
Cont"olled D"illing Techni5ue (contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
103/372
+his will allow for time to heal the suspected
formation.
:t will also pre!ent instant cutting loading in the
well annulus.
1&$
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
104/372
4&LL #LNNIN7TO
*OID MUD LOSS
1&*
#lanning spects
Proper casing setting depths.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
105/372
Proper casing and hole sie combination
Pre-drilling meetings'spud meetings
#ounding ' alerting all concerned
1&(
Contd
# ffi i t l i l ti t l t i l
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
106/372
#ufficient loss circulation control material.
rilling of pilot hole.
Chec) list
1&8
#"ope" Casing Setting Depths
Casing setting depths to be carefully selected
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
107/372
Casing setting depths to be carefully selected
based on a!ailable prognostic data. Fracture prone formations ' ones to be
isolated with casing before opening a higherpressure regime formation.
Proper care should be ta)en to ma)enecessary corrections in geological prognosis5if any5 duringthe course of drilling
1&;
#"ope" Casing SiEe and 'ole SiEeCo,/ination
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
108/372
Eased on pore pressure and fracture gradients5proper combination of casing 0 hole sie to be
selected to limit C effects.
Birtual hydraulic programmes to be utilied to
simulate the situation based on casing O5
hole sie and planned mud system.
1&3
#"e-d"illing Meetings; Spud Meetings
Offset well data should be studied carefully and
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
109/372
necessary recommendations should beincorporated in spud meeting minutes.
uring the course of drilling5 regular safety
meeting may be held to )eep contingency plan in
place.
+his will also wor) as a reminder to all concerned
about best drilling practices while drilling through
a loss prone formation.
1&>
Sounding ; le"ting ll Conce"ned
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
110/372
FEefore opening loss prone formation 5 all
concerned should be informed ' alerted about the
haards in!ol!ed and le!el of preparedness
re,uired .4
11&
Sufficient Loss Ci"culation Cont"olMate"ial
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
111/372
DEased on off-set well data 5 before drilling into
loss prone one5 sufficient ,uantity of suitable
loss control material to be )ept at drill
site'accessible location.4
111
D"illing of #ilot 'oles
One or more smaller pilot holes may be drilled
before enlarging it to the re,uired sie
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
112/372
before enlarging it to the re,uired sie.
+his will reduce e/posed surface area of well bore5
reduce annulus loading with formation cuttings and
allow for healing of formation with time.
+his is especially helpful in the top section of the
well.
112
Chec? List
Offset well data'reports a!ailable and studied.
Procedure for necessary action in case of lost
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
113/372
Procedure for necessary action in case of lost
circulation is a!ailable.
+ype and amount of LC= material that may be
re,uired based on offset data is a!ailable.
:dentify and maintain sufficient stoc)s of LC=material at site.
Communication networ) amongst all concerned
to meet e!entualities.
11$
Contd
Roles and responsibilities of each of the
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
114/372
Roles and responsibilities of each of the
drilling crew members be defined to tac)le a
mud loss situation.
:n case of e/pected surface seepage5 all li)elyspots identified and monitored.
11*
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
115/372
CS&
STUDI&S
11(
FCase Stud.-18-('3 D casing was lowered with shoe at 1(8&
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
116/372
m.+ransition one was at 1>$( m. #imultaneous loss-acti!ity situation was
encountered causing considerable loss of rig
time.
:n Langnese -( 5 >-('34 casing was planned 0
set ust abo!e high pressure one6 into the
transition one9.
+he well was successfully completed withoutany complication.
118
I,p"ope" Inte",ediate Casing SettingDepth
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
117/372
T"ansition Eone at 1A ,
-;8 casing shoe-1>% ,
4ea? fo",ation H,ud loss
'igh p"essu"e Eone-
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
118/372
d"illing data:
:t was planned to lower intermediate >-('34
casing at $(3& m as per G+O.
:n the final section mud weight re,uirement as
per G+O was 2.1( sp.gr.
uring course of drilling well acti!ity was
encountered at around $$2$ m. =ud wt.
gradually increased to 1.82 sp.gr. LO+ !alue for 12-1'*4 phase was - 1.(2 sp.gr. 113
Contd
G+O was re!iewed based on actual data and
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
119/372
casing was lowered with casing shoe at $$;3m against a plan of $(3&m.
+his sa!ed wea)er section in 12-1'*4 phasefrom getting fractured by hea!ier mud
re,uirement to drill further.
11>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
120/372
Ch-A:C&M&NT S LCM 4'IL&
DRILLIN7
10%
C&M&NT TR&TM&NT S LCM%sing cement systems can lead to good results5
but the disad!antage is time consuming
process. :t can then damage the permeability or
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
121/372
be lost entirely to the formation
Cement is not acid soluble and can not be
remo!ed once in place.
amage to the formation is permanent
Cement set-time can not be controlled
accurately
Cement drilling damage the drilling fluid
101
LOSS CIRCULTION 4'IL& DRILLIN7
=ost of the LC=
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
122/372
treatments are oftemporary in nature and
should create a barrier to
withstand the effects of
drilling such as surgeand swab pressures5 and
remo!able by etting '
washing.
100
"idging agents effecti$e upto J inch
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
123/372
Ce,ent slu""ies can seal J inch to 1 ft
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
124/372
setting p"ope"tiesCe,ent s.ste,s that gel up
Thi3ot"opic s.ste,s
7el o" set up instantaneousl. due to
che,ical "eactions
o",ation of filte" ca?e assisted /. lost
ci"culation p"e$ention additi$es
10B
Thi3ot"opic s.ste,
C=@+:@G #T#+=#
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
125/372
Sodiu, silicate and ce,ent
#o"tland ce,ent
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
126/372
st"uctu"e
SODIUM SILICT& ND C&M&NT
#o"tland ce,ent
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
127/372
5 .
Space" fluid "e5ui"ed to p"e$ent ha"dening
in the pipe
S,all space" fluid $olu,e) co,ponents,a. "eact in the pipe
La"ge space" fluid $olu,e) co,ponents
sepa"ated and p"e$ent the "apid setup10=
POR+L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
128/372
sulfate can seal off lost ci"culation Eones
Set ti,es can /e cont"olled /.
pe"centage of calciu, sulfate p"esent
to so,e e3tent /. ce,ent "eta"de"s
Re5ui"es ca"eful d". /lending
10
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
129/372
oth of these ,ethods a"e 5uite "is?.)and e3t"e,e ca"e ,ust /e used to
ensu"e that the ce,ent sets in the lost
Eone) not in the d"ill pipe
10
Massi$e Losses in Ca"/onate o",ations
Carbonate formations li)e limestone and dolomite fre,uently ha!e!ugs5 fractures5 or open channels filled with normally pressuredfluids.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
130/372
+his type of ultra high permeability lost circulation is difficult tocure with con!entional LC= bridging agents.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
131/372
de!elopment. =agnesium base and thi/otropic cement are more effecti!e and
forms rapid gels to resist being wash out. #odium silicate with cement also pro!ides effecti!e results Cement slurry with synthetic fibers and bridging material pro!ides
effecti!e filter ca)e deposition. :f the pill failed to follow the losses path at least some minimumdistance from wellbore5 losses can return.
Losses can also occur if bit side trac)s or penetrates the new path.
Loss one is not always at bit5
1A1
F:ER C=@+
Ine"t
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
132/372
solids f"o, slu"". p"e$enting fu"the" loss
i/e"s in con9unction
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
133/372
1$$
Fiber based LC=
=icronied synthetic fibers
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
134/372
#ie" 12mm5 8mm and
*mm
=i/ing" prior to pumping
Good fluidity @o pumping problem
Cross-netting
1AB
#OLB# #BR LO## C:RC%L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
135/372
can be designed for +otalloss circulation while drilling
1A
ER:G
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
136/372
1A>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
137/372
< slurry of rapid settingmaterial 5 acti!ated withtemperature5 sets at rightangle5 e/hibits similarcharacteristics asportland cement but?>& acid soluble. :t canbe pumped through theEA< to combat all static
or dynamic losses.1A=
Magnesiu, ase Ce,ent
+he magnesium based pills are downhole acti!ated blends ofinorganic5 al)aline earth compounds
d$antages :
t i i l i i h dli i t C l t
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
138/372
oes not re,uire special mi/ing or handling e,uipment. Completeacid solubility5 but reaction is se!erely limited. Aigh compressi!estrength and low shrin)age. #ets and gains full strength rapidly5 thusminimiing lost rig time
#"epa"ation and #lace,ent:
Reta"de" 2 $iscosifie" is added into a mi/ing tan) containing freshwater or brine followed by the re,uired amount of magnesium andallowed to stir until well blended. ead burned magnesite is addedand the slurry is displaced downhole. Pull the pipe to a safe pointabo!e the pill and wait the recommended time prior to circulating or
drilling.
1A
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
139/372
1A
LIMITTION O C&M&NTIN7 SOLUTIONS
Cement slurries not effecti!e against induced !ertical
fractures.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
140/372
:f fluids flowing within the fracture or from an upper
one into the fracture 6cross flow95 the cement slurry
wash away and no seal obtain.
:n case of flowing within the fracture circulation
restored but loss reoccurs when plug drilled out
:n case of cross flow5 no cement slurry found at all
1B%
+o be effecti!e5 the loss control techni,ue and materialsmust be functionally related.
F il d t t bli h l
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
141/372
Failed to establish loss-one. Lost circulation materials are not matches to the typeand se!erity of loss-one
Reluctant to apply proper techni,ue to match these!erity.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
142/372
LOST CIRCULTION #R&*&NTION
DURIN7 #RIMR@ C&M&NTIN7
1B0
Loss 4hile Ce,enting Lost circulation problems while cementing may re,uire Dfoam
cement45 lightweight slurries5 or stage cementing to limit C andfinal hydrostatic pressure.
Cement plugs used to seal a loss one often fail as a result of their
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
143/372
Cement plugs used to seal a loss one often fail as a result of theirdensity. Reducing cement density also reduces compressi!e strengthand bond strength. Lower density slurries can also reduce muddisplacement efficiency.
Ceramic microspheres can reduce the density as low as >.& lbs'gal. Foam cements ha!e also been used for reducing the cement
slurry density below 1& lbs'gal. +ypical densities ha!e ranged from 3.& to >.& lbs'gal.
Often5 losses are such that drilling blind 6with no returns9 is used to
drill through the loss one and into a competent formation prior torunning casing.
1BA
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
144/372
Lost circulation during primary cementing operations
re,uires e/pensi!e remedial wor) and some of the
damages are permanent.
PRB@+:O@
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
145/372
:nade,uate fill-up across potentially corrosi!e water
ones
Lea)ing gas ones behind the casing
:nade,uate casing support to sustain stress offurther operations
Casing not ade,uately supported to resist collapse
from flowing salt sections
@on fulfillment of regulatory re,uirement1B
FR F
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
146/372
Lost ci"culation often caused du"ing this
phase e$en
C
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
147/372
,a3i,u, "unning speeds fo" a gi$en set ofhole conditions
Conside"ation fo" d"illing fluids thi3ot"opic
/uildup due to little o" no ,o$e,ent Ci"culation should /e /"o?en at f"e5uent
inte"$als in cased and open hole section
1B=
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
148/372
PRB@+:O@ ET #:=%L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
149/372
2&
&&
*&&&
Welle!iation
1.& 1.2 1.* 1.8 1.3 2.&
g
Formation Press.
Frac
Pore
&
2&&&
*&&&
m
'4#(S)*+
/4
#(S)*+
1*>
%#%
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
150/372
to type and se!erity of the loss one
:nade,uate records of the past e/perience
rilling mud brea)s through the cement plug before itsets
Lac) of sufficient information and wrong treatment
results repetiti!e failures and costs' time o!errun1%
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
151/372
ER:F OF LO## C:RC%L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
152/372
10
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
153/372
one may be determined with the )nowledgea!ailable at the rig site asV formation and operation.:t is established that more than half of losses onesoccur ust below the pre!ious casing shoe.
etermine the se!erity of mud loss" etermine the
rate of loss and static mud column height. Calculate the pressure of loss-one Calculate the static mud weight which the one will
support.
1A
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
154/372
1B
=ethods of treatment #onventional 0ost #irculation 1aterials, fibers, flakes, and
granules
igh 2luid 0oss Squee3es, diatomaceous earth or clay blends
+unks, $!4 to $!45#
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
155/372
+unks, $!4 to $!45#
Precipitated #hemical Slurries, silicate and late6
Resin-#oated Sand
#rosslinked Polymer Slurries, PP(, guar, "#, etc.
#ements
4arite Plugs
$ilatant Slurries
1
Con!entional -LC= +he most successful use of con!entional LC= occurs with a mi/ture
of types and particle sies. :n some cases5 as much as ;& to 3&lbs'bbl of a mi/ture of LC= should be used as a pill. Generally5 aconcentration of *& lbs'bbl of a properly sied LC= will stop losses to
permeable or fracture ones. < combination of fiber5 fla)es5 andgranular material should be part of the same pill < typical mi/ture
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
156/372
p 5 5granular material should be part of the same pill. < typical mi/turewould be * parts granular5 2 parts fiber5 and 1 part fla)e.
+he con!entional pill should be as !iscous as possible for ease ofpumping and displacement. Bolumes of con!entional pills may !ary
from 2& to 1&& bbl5 depending upon hole sie and se!erity of loss.+he pill should be made with the fluid ma)e-up water for water baseapplications and with the oil or synthetic for non-water systems.
:f LC= materials of greater sie ieV more than 1'$ of nole dia.5 it is
recommended that they be pumped through open ended drill pipe.1>
Con!entional-LC=
+he )ey to sol!ing lost circulation using con!entional LC= isto ha!e sufficiently large particles to first bridge the largestopenings of the pores or in the fracture with rigid granular
LC= materials and second seal the bridged opening withdeformable fibrous and fla)ed LC= material used
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
157/372
g p gdeformable fibrous and fla)ed LC= material used.
Con!entional LC=s can be classified by the particle shapeinto 19 fibers5 29 fla)es5 and $9 granules.
=ost LC=s are waste by-products of other industries5particularly agricultural5 and their a!ailability may !arydepending on the location.
=ost con!entional LC=s are labels as being Dfine45 Dmedium45or Dcoarse45 there are no standards.
1=
LC= Plugging =echanism Eridging agents form a bridge of particles across the fracture or
collect in the interstices of a permeable one. For a bridge to form5
the bridging agent must contain particles that are no smaller than S
of the opening sie to be bridged. +his is true for either permeable or
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
158/372
p g g pfractured loss ones.
Eecause it is hard to )now the sie of a fracture or the sie of the
pores in a loss one5 lost circulation materials that use bridgingagents must contain a selection of !arious lost circulation materials. %
7un? Slu""ies Gun) slurries are downhole acti!ated plugs consist of a high
concentration of hydratable materials in diesel oil and are acti!atedwhen they become mi/ed with mud as they e/it the bit. +hey areespecially applicable to conditions with high static losses.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
161/372
Gun)s ha!e a low !iscosity inside the drill pipe and can generally bepumped through the bit. When placing a gun) slurry5 the gun) isgenerally pumped with a cement unit down the drill Pipe.
:t is highly desirable to pump gun) slurries using two pump rates one ratio high enough to allow a less !iscous material to penetrate5followed by a lower ratio so that a more !iscous material is placed atthe end.
1>1
7un? Slu""ies +he most common are" iesel Oil K Eentonite 6OE9 iesel Oil K Eentonite K Cement 6OEC9
iesel Oil K Eentonite K 2 Cement 6OE2C9 iesel Oil K
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
162/372
p g y 6 9
#lurries without cement do not de!elop true compressi!e strengthand would not be long term solutions to situations where a highdifferential pressure is e/pected.
+he industry generally considers OE2C to be one of the best lostcirculation remedies a!ailable. OE2C has the main ad!antages ofgun) in being able to generate e/treme and immediate downhole!iscosity to slow and seal losses5 plus the ad!antages of cement to
withstand differential pressures.1>0
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
163/372
Diesel Oil;entonite;Ce,ent (DOC) DO0C! iesel Oil Eentonite Cement 6OEC9 is a hydration-type plug . +he cement
allows the pill to de!elop compressi!e strength o!er time.
+he ratio of bentonite and cement can be !aried to alter the final compressi!e
strength. +he final strength of OEC is determined by the pumping ratio of
OEC to fluid and the bentonite to cement ratio. +he starting ratio of the fluid toOEC is usually * to 1 and produces progressi!ely firmer plugs as the ratio of
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
164/372
OEC is usually * to 1 and produces progressi!ely firmer plugs as the ratio of
fluid to OEC decreases to 1"$.
OEC is intended for those difficult situations where con!entional lost circulation
materials and OE ha!e failed. Low to/icity oils5 such as mineral5 synthetic based5 or !egetable oils5 may be
suitable5 but should not be used before laboratory e!aluation for suitability.
+he synthetic based fluids are recommended when en!ironmental regulations
preclude the use of diesel or mineral oil.
1>B
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
165/372
Mi3ing Re5ui"e,ents +wo cement pumping units should be used for a OEC s,ueee. One pumping unit will
pump the OEC down the drillstring and the second unit will pump fluid down the annulus.
+he presence of water in the base oil causes acti!ation of the slurry to a degree relati!e tothe
contamination. +he result will be seen in higher !iscosity and lower slurry density due to the
water acti!ating the cement to set. #teps to dry the water from the oil prior to adding the
cement allows a higher concentration of cement to be added into the oil.
+he oil should be either )erosene5 diesel oil or other suitable oil.
+he moisture content of the bentonite will also affect the results.
1>
Contd. #"epa"ation Pilot test the OEC and a,ueous fluid mi/ ratios to !isually obser!e
the results.
etermine the !olume of OEC to be pumped. +ypically5 a *& barrel
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
166/372
batch is used5 but site specific conditions should be considered.
Flush all pumps5 mi/ers5 lines5 and tan)s that will be used to prepare
the OEC with diesel oil.
fluid or water in the suction lines and pumps. < low pressure gauge installed to monitor s,ueee pressure .
:nstall a bac) pressure !al!e in the drillstring.
1>>
Contd. #lace,ent Pump ( to 1& barrels of diesel oil spacer followed by the OEC pill and
another ( to 1& barrels of diesel oil spacer to isolate the OEC from the
fluid. Pump enough fluid to place the bottom of the pill at the bottom of the
pipe. Close the pre!enters and commence pumping down the drillstring at a
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
167/372
Close the pre!enters and commence pumping down the drillstring at a
ma/imum rate of * to 3 barrels per minute. =onitor annular pressure gauge
reading and control the pressure to a ma/imum e,ui!alent of 1.( ppg fluid
weight. =aintain pressure on the well for appro/imately $ hours. Circulate
and condition the fluid at the bottom of the casing for at least two annulafluid !olumes while carefully monitoring for fluid loss before tripping the
pipe.
Circulate and condition the fluid at the casing shoe before entering the open
hole. Wash and ream the open hole slowly to a!oid pushing the bit into the OEC and possibly pressuring up the hole.1>=
DO
O
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
168/372
11;.3 lbs of attapulgite
>8.* lbs of bentonite.
+he mi/ture yield is appro/imately 1 bbl and the slurry density is 1&.8 lbs'gal
62 diesel9.
Silicate 2 Late3 Slu""ies Eoth sodium silicate solutions and commercial late/ additi!es used for
cementing can be made to precipitate and plug loss ones when pumped in
combination with calcium chloride. +he general scheme is to pump a calcium
chloride pill followed by the silicate of late/ slurry. When these two slurriesmi/ in the open hole hopefully adacent to the loss one they form a !iscous
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
169/372
mi/ in the open hole hopefully adacent to the loss one5 they form a !iscous
plug which can slow and seal many loss ones.
While sodium silicate has been used for many years in combination with los
circulation while cementing5 late/ appears to ha!e the potential for beingsignificantly more effecti!e .
Late/ reacts faster5 forms a cohesi!e mass5 and is applicable in oil-base muds. Oil
base mud also acts as an acti!ator of late/ so that mud contamination would not
necessarily render the slurry ineffecti!e
1>
U-Lin) LC= For Reliable Circulation Control
Formulation remained li,uidand gelling started only afteraddition of the acti!ator
G l ti i d b
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
170/372
Gelation period can becontrolled as perre,uirement
Form Polymeric stiff rubberygel to create impermeablebarrier at the lost one
C"osslin?ed #ol.,e"s Guar gum has been used for many years to build lost circulation pills of a
!ery stiff5 plug-li)e consistency when an acti!ating chemical is added. PAP
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
177/372
1==
ER:G
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
178/372
1=
#:B 1"-(&&Xm
2"-2.&mm
$"-*.&mm#L:+ *"-$.&mm
ifferent sie of
Perforated plate"-
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
179/372
$ *
12
1=
Ch-*"
C
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
180/372
C:RC%L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
181/372
WA@ LO#+ C:RC%L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
182/372
p
Carbonate formation" swift loss
#hale formations" slower 0 progressi!e
:nformation pertained to operations
Change in mud weight
Rapid mo!ement of the drillstring
10
CORRC+:B =
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
183/372
and match the remedial material and techni,ue to it
in terms of both the sie of the material and itNs
return
1A
C
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
184/372
LC= s are not systematically matched.
Reluctant to proceed with re,uired techni,ue.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
185/372
1
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
186/372
1>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
187/372
1=
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
188/372
1
DIS#&RSIL& I&RS
=icronied synthetic fibers
#ie" 12mm5 8mm and *mm
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
189/372
5
=i/ing" prior to pumping
Good fluidity
@o pumping problem
Cross-netting
Disersi!le Fi!ers1
ER:G
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
190/372
1%
LC=" CRO##-L:@ GL
Cross-lin)ed polymer gel used as LC=
pro!ides circulation lost control
While drilling
Polymer based gel shrin) with time and
reopen the fractures
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
191/372
reopen the fractures.
#uch LC= may starts cross flow
Polymer gel may stic) to formation and
can damage the permeability
=ost of the gels are not biodegradable or
can not be remo!ed.
11
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
192/372
10
I&LD IM#L&M&NTTION O
C'&MICLL@ CTI*T&DCROSS-LIN&D #OL@M&R 7&L
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
193/372
S LOSS CONTROL #ILL
1A
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
194/372
Se5uence of Loss Cont"olOpe"ation du"ing d"illing
Loss-Eone at 0%M
#laced %B LCM #ills 0 '#L4 Ce,entslu"".61.(2-1.(&9
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
195/372
El drilling u.t. 231&.(=
@o ret. Cont. drilling-*m LC= Pills at 231*.(=
@o returned
1
Elind drilling upto 231>.(=
#tatic mud le!el at 1*&-1(&=
Placed 2 LC= pills K $ cement plugs
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
196/372
@o returned
#tatic =ud le!el at 11&-12&=
Placed Cross-lin)ed Polymeric Gel followed
cement plugs 6sp gr 1.8*9
1>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
197/372
1=
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
198/372
1
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
199/372
CS& STUD@ O 4&LL
*S&G1>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
200/372
0%%
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
201/372
0%1
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
202/372
0%0
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
203/372
0%A
esigned formulation acti!ated
abo!e *2-*(&C. Planed to use
accelerator for low temperature
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
204/372
accelerator for low temperature
$8&
C6Y*2&
C9.
0%B
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
205/372
0%
Made a""ange,ents fo" > tu/e
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
206/372
0%>
&ffo"ts to
o$e"co,eloss
Water based drilling
fluid" =W 1.&$-
1.&(5Bis. *&-*3 sec. uring loss control
=W" &.>(-&.3(
epth
m
Eentonite
in +ons
Chemicals in )g
*12 *.> PAP 1&.& #-2&bgs5 cement-1&bgs5 A#-2&<5
=anila rope-(bgs etc
*3& *.; =ica-8;5 carpet fib-*bgs5rope fib-;bgs5
Gunny bag fib-1&bags
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
207/372
Bis $3-*3 sec
----%sed surfactant to
reduced =W
y g g
*>3 2.& =ica-1(&)g5#-;bgs5 rope fib-(bgs
(&* 1.** =ica-(&5 rope fib-2bgs5 #-2bags
(18 &.8& =ica-1&&5rope fib-(bgs5#-2bgs
(22 1.33 =ica-2&&5rope fib-(bgs
0%=
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
208/372
2 Lead APLW slurry with&.2( fiber5 #p gr-1.*8
12.& 1$.&
$ +ail APLW slurry with outfiber5 #p gr-1.*8
12.& 1*.&
F:@:@G"- F%LL R+%R@5@O LO##0%
CONCLUSIONS
Plugging efficiency of cement slurries has impro!ed by
solids and fibers.
Fiber concentration of &.2(6EWOE9 for light weight
cement slurries 6sp gr 1.(& ' 1.2(9 is an ideal system.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
209/372
cement slurries 6sp gr 1.(& ' 1.2(9 is an ideal system.
LC= based cementation may pro!ide successful solution.
Elend of fibers in cement slurry may gi!e most effecti!e
sealing of fracture formation
0%
:nno!ati!e Lost Circulation Plug to rill
successfully 12 Z4 hole" Practical#olutions
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
210/372
01%
:nno!ati!e lost circulation
materialLi,uid of low !iscosity61&-12cp9/panded 8-> times
#et mass is lighter than water :nert to acid and al)ali specific gra!ity-1.&8
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
211/372
011
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
212/372
FO
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
213/372
=OL# @O1" C'# 1&&P#:5 2" C'# (&& P#: and $" C'# 3(&P#:
1 2 $
s'g 1.1 1.$ 1.*
01A
FO
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
214/372
< E C
01B
C=@+ #L%RRT :@ W
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
215/372
R" Foam cement slurry
of 1.13 s. g
01
Ch-:
MUD LOSS #R&*&NTIONROM DRILLIN7 LUID&N7IN&&RIN7 #OINT O *I&4
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
216/372
&N7IN&&RIN7 #OINT O *I&4
218
#R&*&NTION O MUD LOSS
Pre!ention is better than cure
+wo aspects of pre!ention are
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
217/372
1. Formation strengthening-for wea) formation
2. #ub hydrostatic fluids - for low formation pressure
01=
Pre-re,uisites of formation strengthening
concept are "
1. Fracture strength of the roc) by lea) off test
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
218/372
g y
6LO+9 or pressure integrity test6P:+9.
2. Pore pressure of formation.
01
Causes of low !alues of fracture strength are"
1. Poor cementing ' binding material between
roc) grains or matri/
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
219/372
roc) grains or matri/
2. =icro fractures in the roc) matri/
$. Roc) fluid interaction
01
#trength of wea) formations can be increased
by"
1. Formation sealing materials
2 #ystem loss circulation materials
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
220/372
2. #ystem loss circulation materials
$. @on in!asi!e fluids
*. Cement s,ueeing
00%
1.Formation sealing materials
+hese materials are"
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
221/372
1. #ulphonated asphalt
2. Gilsonite
001
Sulphonated asphalt
:t seals micro-fractures.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
222/372
pp p g
:t strengthens wea) formations and pre!ents
losses in such formations.
:t stabilies borehole shale #tability.
000
7ilsonite
:t is a mineral which seals micro-fractures.
:t stabilies and plasters borehole walls.
:t strengthens the wea) formations and
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
223/372
g
pre!ents losses.
osages !ary from 2-8 lbs'bbl.
00A
2. S.ste, lost ci"culation ,ate"ials (LCM!
#pecially selected sied particulate matter.
Particle sie distribution is based on e/pected
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
224/372
width of largest fracture.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
225/372
p
+hey pre!ent or minimie losses.
00
Co,,onl. used s.ste, LCMs a"e :
1. #ied Calcium Carbonate Large5 =edium5
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
226/372
Fine and =icronied
2. Graphite
$. #ied olomite Lime #tone
00>
SiEed Calciu, Ca"/onate
< blend of calcium carbonate particles of
different micron sies.
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
227/372
Preferred to minimie or pre!ent losses in
limestone reser!oirs
Can be subse,uently remo!ed by acidisation.
00=
7"aphite po
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
228/372
Eridge seals the pore throats and micro
fracture and helps pre!ent the mud loss.
00
7"aphite po
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
229/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
230/372
plimestone reser!oirs.
Can be subse,uently remo!ed by acidisation.
0A%
$. Non In$asi$e luids
@o!el concept based on drilling fluidformulation with almost ero in!asion in the
formation
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
231/372
formation.
Propriety compositions which create an
imper!ious barrier within the formation.
0A1
Non In$asi$e luids
Earrier stops further in!asion of the fluid
phase
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
232/372
/erts entire confining pressure of the drilling
fluid on to the well bore.
nhancement of LO+ !alue. 0A0
Non In$asi$e luid
=ay be used to increase LO+ !alue before
increasing mud density.
P t d l d t i t
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
233/372
Pre!ents mud loss and sa!es e/tra casing to
co!er transition one.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
234/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
235/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
236/372
formation.
nhances the strength of the formation.
0A>
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
237/372
SU-'@DROSTTIC DRILLIN7 LUIDS
ensity of drilling fluid is less than that of
water is called #ub hydrostatic drilling fluid.
Reser!oir formations ha!e become sub
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
238/372
Reser!oir formations ha!e become sub-
hydrostatic due to pressure depletion
Pre!ent mud losses in these formations.
0A
*a"ious options of su/ h.d"ostatic d"illing fluids a"e:
1.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
239/372
*. %nder balanced drilling ' =anaged Pressure
drilling 6%E ' =P9
(. =icro Eubbles Proect under Progress by :+
0A
i"; Co,p"essed gas "e5ui"e,ents
1. #pecial drilling infra structure.2. Aard and impermeable formations.$. @o influ/ of water or any other fluid in the
well bore
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
240/372
well bore.
*. nough precautions for possible fire haardor e/plosion.
(. Protection from corrosion.
0B%
oa, ;Sta/le oa,
+he application re,uirements are"
1. #pecial drilling infrastructure.
2. #pecial additi!es for foam generation and
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
241/372
p g
stabilisation.$. Problems of foam disposal
*. Aandling problems of fluid influ/
0B1
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
242/372
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
243/372
'ollo< 7lass Sphe"es ('7S!
asy to prepare and maintain drilling fluidwith AG#
@o ad!erse effect on mud properties
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
244/372
@o ad!erse effect on mud properties
@o special infrastructure re,uired for its
application
0BB
'ollo< 7lass Sphe"es ('7S!
asy handling and storage
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
245/372
@on abrasi!e
@on corrosi!e0B
'7S pplication in ON7C
1. First field trial in drilling fluid is carried out on
well :P1&A and :P11Ain western offshore
by maintaining the mud weight ;.$-3.& ppg.
2. +hree types of sub-hydrostatic drilling fluids
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
246/372
yp y g
designed by :+ using AG# for =umbaiAigh
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
247/372
*.+he designed drilling fluids of density ;.(ppg showed good rheological and filtration
properties. oses is !arries from 2(-$&.
0B=
'7S pplication in ON7C
(. +he AG# based sub hydrostatic drilling fluidhas shown retention of specific gra!ity e!enafter application of *&&& psi pressure at >& cfor 3 hours
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
248/372
for 3 hours.
8. +he sub-hydrostatic wor) o!er fluid up to#.G. &.8( was also designed using hollowglass spheres.
0B
'7S pplication in ON7C
;. =any assets and basins ha!e shown )eeninterest in sub-hydrostatic drilling and wor)o!er fluids for field application in their areas.
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
249/372
3. +hese sub hydrostatic fluids are e/pected topre!ent mud losses in wea) and depletedformations.
0B
'7S pplication in ON7C
>. +hese fluids are also e/pected to minimie
formation damage and shall enhanceproducti!ity of the reser!oir.
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
250/372
1&. +he sub hydrostatic wor) o!er fluids shallpre!ent losses during well completions and
wor) o!er operations
0%
Unde" alanced D"illing (UD! ; Managed#"essu"e D"illing (M#D!
Pressure of the mud column is less thanformation pressure
#pecial drilling infrastructure re,uired
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
251/372
p g ,
@o chance of inducing fracture +otal control and monitoring of well bore
pressures Problem of mud loss eliminated
01
Mic"o u//les /ased d"illing fluids
Concept to formulate the drilling fluid to beused in drilling and mitigate the mud losscomplication in depleted Reser!oir ' mud lossprone area.
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
252/372
Formulation of stabilied micro-bubbles baseddrilling fluids to control mud loss
00
Mic"o u//les /ased d"illing fluids
#table micro-bubbles can be created with thehelp of certain surfactants and Polymers.
+emperature stability of =icro-bubble is
#R&*&NTION O MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
253/372
p y
11°.C.
Pressure stability of =icro-bubble is *&&&psi
Aa!ing non damaging Characteristic. 0A
Mic"o u//les /ased d"illing fluids
=icro-bubbles is more stable and consists ofsurfactant tri layer.
1.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
254/372
p y
!iscous water shell.
2.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
255/372
2. Restoring circulation ' Controlling mud loss
0
Methods fo" locating the Eone of ,ud loss
a"e:
1. #pinner sur!ey
2. +emperature sur!ey
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
256/372
$. Radioacti!e sur!ey*. +he hot wire sur!ey
(. Pressure transducer sur!ey
0>
1 Spinne" su"$e.
. =ade by running a small spinner attachmenton a single conductor cable
. Rotor will spin or turn if there is anyhoriontal motion of mud
. +he motion of rotor is recorded on film as a
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
257/372
series of dashes. +here is a definite speed up of rotor at the
point of loss
0=
Li,itations of Spinne" su"$e.
Re,uires deliberate loss of large !olume of
mud
@ot effecti!e where sealing material is already
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
258/372
present in mud
0
2. Te,pe"atu"e su"$e.
epends on subsurface thermometer formeasuring difference in mud temperature andformation temperature
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
259/372
Recorded by running a sensiti!e element inhole5 obser!ing resistance change withrespect to temperature
0
2. Te,pe"atu"e su"$e.
+wo sur!eys are run.
One for temperature gradient of well.
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
260/372
Other5 after adding cool mud.
#harp temperature change will occur
at loss point.0>%
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
261/372
B 'ot
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
262/372
resistance is noted
=ud is pumped into the hole
0>0
B 'ot
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
263/372
:f resistance does not change5 tool is below
the point of loss
0>A
#"essu"e t"ansduce" su"$e.
:nstrument composed of hollow cylinder withan entrance at the top5 larger in cross sectionthan the e/it at the bottom
+he geometry of instrument restricts the flow
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
264/372
of mud through the cylinder < window fitted with a neoprene diaphragm on
one side of the cylinder
0>B
#"essu"e t"ansduce" su"$e.
< mo!able electrode on the diaphragm mo!esbac) and forth between two fi/ed electrode
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
265/372
+he potential difference5 indicati!e of rate offlow of mud5 between mo!able and fi/ed
electrode is measured at the surface
0>
#"essu"e t"ansduce" su"$e.
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
266/372
:t is simple in construction and operation :t is not easily clogged by lost circulation
material
0>>
#"essu"e t"ansduce" su"$e.
:t is wor)able in almost any type of mud :t can be used to locate a hole inside the casing.
Li,itations of #"essu"e T"ansduce" Su"$e.
D&T&CTION ;LOCTIN7 MUD LOSS +ON& (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
267/372
.
Considerable mud flow is re,uired
+he e,uipment may not be readily a!ailable
0>=
Ch->:
MUD LOSS CONTROL
ROM DRILLIN7 LUID&N7IN&&RIN7 #OINT O *I&4
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
268/372
283
Loss Ci"culation Cont"ol Mate"ials"
Eridging
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
269/372
OE 6diesel oilKbentonite9 plugs own hole mi/ed Aard plug
OEC 6diesel oilK bentonite K cement9
0>
"idging agents in ,ud
=aterials used to ma)e loss control pills ands,ueeed into the thief one
Eridging materials form an effecti!e e/ternal
Cont"olling Mud Loss (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
270/372
as well as internal seal in the loss one +his reduces or cures the mud loss.
0=%
"idging agents in ,ud ; #ill
Eridging material is of three types"
1. Granular"Wall nut shell5 Coco nut shell andCalcium Carbonate5 #ulphonated
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
271/372
2.Fibrous" #aw dust5 Rice Aush etc.
$. Fla)y" =ica Fla)es0=1
"idging agents in ,ud
:t is always desirable to use a blend of two or
more different types of bridging material toform an effecti!e seal.
+he choice of bridging material depends on
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
272/372
the type of formation in which mud loss occursand also the se!erity of mud loss
0=0
"idging agents in ,ud
< blend of fla)y 5 fibrous and granular bridging
material is recommended for unconsolidatedformations.
< blend of fla)y and fibrous bridging material isrecommended for highly permeable formations< bl d f fib d l b id i
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
273/372
< blend of fibrous and granular bridgingmaterial is recommended for mud loss infractured formation.
0=A
"idging agents in ,ud
Proper sie and types should be mi/ed indrilling fluid for s,ueeing into loss one.
+he total concentration of bridging agent
h ld b b t 2& t (&PPE 6lb 'Ebl9
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
274/372
should be between 2& to (&PPE 6lbs'Ebl9 %se open end drill pipe to accommodate all
types of sies of the bridging materials.
0=B
"idging agents
=ica fla)es
Walnut hulls
Cotton seed hulls
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
275/372
#aw dust
Rice hus)
Eagasse0=
"idging agents
Cellophane fla)es
Leather fla)es Ground plastic =arble chips Gilsonite
+h t bb
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
276/372
+hermo set rubber
'igh filte" loss slu"".
Pill of the material slurry pumped in the oneof mud loss. .g. Aigh !iscous GelKLime
#lurry losses all its fluid phase to the
formations adacent to the loss one
CONTROLLIN7 MUD LOSS (Contd!
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
277/372
formations adacent to the loss one Remaining solid mass forms a tough and
effecti!e seal in the loss one
0==
Do
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
278/372
with water and the Eentonite powder swells toform a thic) and soft plug within the loss one
to pre!ent further loss.
0=
Do
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
279/372
loss one One such soft plug is prepared by mi/ing high
percentage of bentonite in diesel oil
0=
Do
-
7/24/2019 Mud Loss Course Powerpoint-RJY-11 Feb 2013
280/372
these plugs is generally 1"1 or 1"2.