Low Temperatur Cementing

8/20/2019 Low Temperatur Cementing

1/8

A Study of

Low

T cIl lpe ..atu ..c

Ce:m.enting

By W THORVALDSON

(J3th Annual

T ec hn ic al M ee ti ng , C al ga ry , M ay ,

962

STR CT

Since

1957

Dowel l o f Canada has

been conducting

a survey,

in

th e

field an d in th e laboratory, of tem

per at ur es and cementing

strengths

encountered

drilling

in Western

Canada. In an attempt to

rectify

th e

seemingly

i nadequa te cement

s tr engths , several different correc

tive

measures have

been developed,

tested

an d eva luat ed . This paper is

designed to

q u ~ n t th e

i n d u s ~ r y

with

th e

investigatIOn from

th e

mI

t ia l surveys to th e successful cem

enting of a string of

casing

wholly

in perma frost.

INTRODUCTION

W

ELL temperatures

exert

a pro

found

effect

on th e setting

propert ies o f cement

slurries.

Con

sequently, cements must be

carc·

fully formulated so that

adequate

thickening times are obtained fo r a

proper placement

of

th e s lu rry, yet

WOC times

are not

unduly pro

longed.

In the Canadian oil f ields,

especially during the winter

month s, low

temperatures present

a formidable problem,

especially

in

setting

surface casing,

where

th e

formation temperature i s below th e

freezing

point of water_ Oddly

enough. very few d at a a re available

on formation

temperatures

in

th e

depth range

of surface

casing,

or

th e

effects that

these temperatures

have upon cementing practices.

The range

of surface

tempera-

W

M . T ho rv al ds on , Dowen

of

Canada, Division

of

Dow Chmni-

ca l

of Canada, Ltd., Cal.gary, Al -

berta.

64

tures encountered

is

shown

in Fig-

1O'e

1, which

shows

th e

mean tem

peratures characteristic of this

area. Assuming a liberal

temp

erature

gradient

of 2°F. per 100

feet

an d an

average

surface

pipe

depth of 600 feet, it may be seen

that th e B.H.T. varies

from

approx·

imately 50°F . in t he sou th to

17°F.

in

th e

north.

These

temperatures,

although modified

by

th e penetra

tion o f d ri ll ing fluids, are danger

ously

close

to an d

often

below th e

minimum temperature necessary

fo r

t he s et ti ng

of

commonly

used

cements.

As

a n e xampl e

o f th e fo rmatio n

temperatures usual ly encountered

Fignre

2 shows

t he t empe ra tu re

profiles

of two wells

surveyed under

static conditions.

One

of these

wells was located at

Resolute

Bay,

N.W,T_,

th e

other

in

northern

Alaska. Both

of

these

wells are in

th e continuous Perma-frost zone,

indicating

from

1000 to

5

feet

o f Perma-f rost .

Low

TEMPERATURE

CEMENTING

as to accumulate pert inen t

well data

and

perhaps anticipate

potential low temperature

prob

lems,

an extensive investigation of

well

temperaturcs

during

cementing

operations was conducted, studying

wells

in a ll sec tions

of the country

and at a ll seasons of th e

year.

Sub·

surface temperatures were

measur

ed using a

bottom

hole recording

**Metereological Survey

of

Canada.

thermometer

in

some

SUI VC YS.

a

n<

utilizing Surface

Recording Contin

uous

Surveys on o ther s.

A typical survey, made in Centrn

Alberta, is

shown

in j i ' igl l l ( 3. A

total

of

300 sacJ s

o f n ormal

( em

en t slurry containing 2(,;· C akium

chloride accelerator (slur ry weight

14.5 lbs. per

gallon) wa s

used t

cement 303 feet of 107. i.

inC 1l

dia

meter

surface

casing. SUl faee tpm

perature was 20

F. ;

that of tll

slurry was

32 F.

CirCUlating tem

perature was 40 F. an d tile temp

erature of th e

s lu rry n ·turns wa

36 F. Thi s cha rt shows

the record

ed

temperatures

at three diffet pn

wel l dcp ths, as recorded at inter

mittent

time

intervals.

A

similar

example is

shown

i

FigllTe 4. This

well. loeated

in

Northern

Alberta, require(l -la

sacks of oil well ( cment

containin

2 /

c alc ium chlo ri de

aceelerato

(slurrv wcight, 1 1.7

lbs. pC r gallon

in onjer to cement

620

feet of 10

inch surface casing. ]n tlIis casl

surface tempemture was 20 F

while

that

of

th e

slurry

was


2/8

igure I . -Map of princ ipal

Canadian

oil f ie lds

showing

mean temperature isotherms.

vice of CanadaJ

MetereologicaI Ser-

14.5

lbs.

pe r

gallon)

to

cement

491

feet of 8

diameter surface

casing.

Surface temperature

was

20°F.

that

of th e

slurry when int roduced into

th e well was

38°F.,

an d th e circu-

lating temperature was recorded as

40°F. The t empe ra tu re

changes

occurring at th e 420

it depth, dur

in g the first 12 hours following

slurry placement, ar e s hown. This

particUlar cementing

jo b failed

after

24

hours shut-in

time.

A series of laboratory

tests

was

conducted t o det ermine th e com·

TechnologYr

umm r

r

96 lg ry

pressive

strengths

obtainable

from

oi l well cement

slurries

containing

2 calc ium chlori de accele ra to r,

an d

having

a slurry

weight

of 15.6

lbs. per gallon,

allowed

to

se t

t empe ra tu re s r anging f rom 40° to

70°F.

The compressive strengths

attained over a 30-hour per iod are

shown

graphically

in igure

In Canadian oi l field cementing

operations,

most

c ommon ly u se d

slurries f or sur fa ce casing strings

are 15

lbs. per gallon or

less.

Out

of 160 cementing

jobs

evaluated,

only

24

used

slurries

that

were

heavier than 15.2 lbs. pe r gallon.

As

may

be

seen

in

igure

7 which

shows

Z4 hour

compressive

strengths

fo r dif ferent weight slur ries dif-

ferent temperatures ,

a

reduct ion in

slurry weight

resu lts i n

a corres

pondingly lowered compressive

strength.

I t

will

be

noted

however

that

increased

strength

is

attain·

able fo r lower weight slurries by

increasing their curing

temperature.

For example, 6 hours at 70°F.

produced a compressive strength of

65


3/8

404 psi,

whereas the same

slurry

in

6 hours at

50°F.

had only a com

pressive strength

of 38 psi . Thus, a

temperature in cre as e o f only

20°F.

re-sulted

in

10 times a s g re at a

com

press ive s tre ng th . Th es e

tests

in

dicated

that

heating

up th e cement

slurry

should

y ie ld benef ic ia l re

sults. insofar

as producing

higher

compressive

strengths

in

the set

cement.

A

number

of

techniques

have been developed to

accomplish

this purpose , and

have

yielded grato

ifying

results

in

the field. In gen

eral,

these techniques

may

be

class

ified

in

three categories: 1 elec

t r ic heat ing;

2 chemical heating;

an d 3 use of h igh Alumina cern·

ents.

ELECTRIC HEATING

METHOD

Electric heating of cement

slur

ries,

a comparatively recent devel

opment,

is

depicted

schematically

in

Figu ·e

8. After th e casing ha s

been cemented, and th e plug dis·

placed, an

e lect ri ca l connect ion i s

made with th e

cas ing and

5

volts

D.C. is applied. Approximately

1000 amps of current flows from th e

cas ing i nt o th e ground.

The

elec

tric circuit is

completed

through

*Patent applied

for.

one or more back-electrodes, loca

ed at a d is tance f rom

th e

we

The

electrical

power

is su pp lie

from a mobile 450 volt, 105

amp

generator, driven by a 700 h.

Allison motor.

In general, field test s showe

that two

types

of

back-electrode

were

suitable fo r this application

(1 )

an

offset

cased

well,

or

2

number of special ly dri ll ed sli

holes containing 2-inch tubing

(n

coverable)

connected

in

paralle

Resu lt s o f field tests compar ing di

ferent types

of installations

an

shown in

Table 1

Figure 2.--Subsurface

temperature

profiles

of two

typical

wells in th e perrna-frost zone, one located

at

Resolute

Bay, N.W.T., and the other

i n Nor th ern

Alaska.

24

WELL

A

CENTR L L ERT

6 12 18

TIME HOURS

1

I

I

f---L

7

I

Oepth: 5

Fl

I

-

Oeplh: 125

Ft

I

r ·

-

--

I

Oep h ;

5

60

40

60

40

60

u

°

_____ NORTH

ALASKA

~ E S O L j U T E \ l j

BAY N.W.T.

w

::>

«

a

:::E

8 0 0 0 c - - - - - c 1 ~ 0 , - - - - ~ 2 0 - - . . . , 3 ~ 0 , - - - - - - - - ; ' 4 0 ~

TEMPERATURE

OF

200

W

W

u

I

400

a

w

0

600

WELL

C

SOUTHERN L ERT

6 0 ~ ~ = = ~ ~ ~ ~

Figure 3.-Temperatur€ survey of well in Central

Alberta,

dur ing sur fa ce

c as in g cementing opera

tions;

temperatures

recorded at 50 ft., 125 ft., and

250 1t. depths.

w

50

or

J

>-

«

40

w

c..

::t

Veplh: 42

Fl

w

>-

30

0 3

6 9

TIME HOURS

o

6

12

TIME HOURS

4

l

-

Vepih: 55 Fi

I

70

WELL

B

NORTHERN

L ERT

60

Figu re 4.-Temperature

survey of wen

in Northern

Alberta, dur ing sur fa ce ca sin g c ementin g ope ra

tions; temperatures recorded at 550 ft .

depth.

Figure 5.-Temperature sur vey o f

well in

Southern

Alberta, during

surface

casing cementing

operations;

temperatures

recorded at 420 f t. d ep th .

66

ournal

anadian Petroleum


4/8

TABLE

Low

Temperature Cementing Jobs Using

Electric

Heating

700

1000

1025

1000

0' .54

10 '

120' /60' .43

120' /60' .46

120' .72

1

10

4

2

4

2

2

2

2

2

1

2

Back Electrodes

No. Size Depth

1 5 12 517

1 5 h 4880

1

5 12

3135

197'

700'

700'

215'

700'

215'

8

Surface Cwing

Size Depth

5 12 333

8 400'

7

420'

8

215'

540 I n p ara ll el w it h 4b

satisfactory

440 With Red Deer

River

in

parallel satisfactory

460 Without Red Deer River

in parallel

satisfactory

505

With Red Deer

River in

parallel unsatisfactory

*Sur fa ce ca sing o f nearby abandoned well u sed

as

back

electrode.

This phase of th e cementing operation

was considered

satisfactory,

m spit e of th e h igh overall

resistance.

The

relatively

shallow

wel l d ep th

(215

ft )

made

possible

sufficient

heating

at

th e

reduced current of

850

amps.

5a

10 '''

5e 10,.

5b 10,.

4c 8

Job

No

1

2

3

4a

4b

n

Western

Canada,

500 ps i is

usually

accepted as a satisfactory minimum

s treng th for drilling out and subsequent hole deepening.

TABLE

II .

Est imated Strength of

Cement Set

with

Electric Heating

Slurry

Estimated

Weight

Oa1Jl

Curing

Electric

Maximu:rn

Compress

Job

Lbs.

Additive

Time

Heating

Temp.

at

Strength

No

U.S. Gal.

Percent

Hou rs

Time Hrs.

Bottom·oF.

ps i

1

15.6 0

6 hrs.;

4

hrs.

117

800

30 min.

2

15.6

2 12

hrs.

7hrs.;

80.5

800

30

min.

3 15.0 2

10

hrs.

8hrs.

83.5 900

4

15.0

2 9

hrs.

6hrs.;

113

1000

40 min.

5

15.0

2

13

hrs.

8hrs.

87.5 1000

ent, th us ra lsmg its tempera tu re.

In effect, th e unset

cement

acts as

a

heating element.

t

was found

that

enough

heat was genera ted i n

the

cement

by

this method

to jus

tify

the

power

losses elsewhere.

Temperature surveys were run

on a

well

i n Central Alberta during

a

cementing

jo b uti lizing elect ric

heating.

Th e

results are shown

in

Figu re

9

Altogether,

250

sacks of

15.6 lbs . per

gal lon cemen t s lu rry,

containi ng 2

calc ium chlo ri de

accelerator, were

used in

this

well.

Surface

temperature

wa s

32°F

•

slurry t emperature was 46°F., and

circulating

t emperature was

53°F.

The

back·electrode

was loeate d 1320

feet

from

the

well.

The

four

curves

shown

in

this

figure represent:

(1 ) Well

temperatures

immediat

ely

after placement of th e

cement

slurry;

(2)

Well

temperatures after

one

hour

shut-in time, no

elec

tric power applied;

(3) Temperature

survey

after

4

1/ 3 hour s o f power applica

tion;

and

survey

after

power

applica-

(4)

Temperature

5

hours of

tion.

121

173

219

262

300

Temperature

Rise

_

OF.

TABLE

Heat

Liberated

by

Chemical Reaction

Lbs.

NaOH

Heat evolved

_per

gal.

Hal

B.T.U.

1.02 1016

1.55 1542

2.11 2106

2.71 2695

3.31 3289

10

15

20

25

3

Hydrochloric

Acid·

Percent

When

the circuit is complete, the

power is

dissipated

in a number

of

ways: (1 )

losses

i n sur face cables;

(2) los ses in

casing;

(3) losses in

unset cement;

(4) losses

through

the earth; and (5) losses in th e

back-electrodes. These power losses

are manifested

in the form

of hea t,

and

th e purpose of the t reatment

is

to

produce

heat

in

th e

unset

cern-

The beneficial

heating

effect

of

the

electric

current

on

th e cement

slurry may

be

seen in Table

II

which shows est imated

compressive

strength data on

five

different

wells

that

were cemented using the

elec-

Technology Summer 962 algary

67


5/8

17 0

15.0 16,0

SLURRY WEIGHT - LB/GAL.

- - -

--t--I -7 o.---I-- ? : --I

,

.

,

7 ·· ._ .

,0°

.

1000

3000, r - - - - : : - : - - - - - : - - r - - - - , - - -_- - - ,

T MP R TUR

70°F

-

60°

F -

50

0

F-············

40

0

F ·_

2000

--------,- .--+1---. . . .-_,

// /

1000

700

-

~ j

. /

-

......

-7/

j

-

I

400

l-

. • I

I

/

I

Z

u.J

200

i .r 1 j

z

u.J

I-

:

/

l-

i

+ i ~ ~ j

< /

u. J

>

100

u.J

>

70


6/8

TABLE IV.

IJaboTatory Tests o f H igh A lumina Cement Slu rries

Slurry

ont press

Slurry

Weight

Strength

Volume

S l l trr y Co mp o si t io n

Lb Gal

A v g. p si

a

ft .

High

Alumina

Neat

15.32

6745

1.160

High Alumina -

Ash

1:1

14.26

960

2 525

High

Alumina - Ash -

8

Gel

13.34

538

3.109

High Alumina - Ash - 10

Gel

13.16

460

3.257

High Alumina

- Litepoz 2

12.6

551

2.31

High

Alumina

- Litepoz 2

12.8

727

2.19

High Alumina - Litepoz 2 -

6 Gel· 4 CaCl

13.45

828

2.09

High Alumina - Litepoz 2 -

8

Gel

-

4

CaCI

13.49

885

2.11

High

Alumina· Litepoz

2 - 10

Gel

- 4

CaCI

13.54

856

2.13

HlGH

ALUMINA CEMENT

The

most

successful approach to

the

low

temperature problem has

been

th e

use of h ig h Alumina cem

ents. normal

cement

freezes

shortly after

th e

initial

se t

has

taken place

th e

water which

ha s

not yet entered into combination

with

th e

cement

expands

and dis

rupts the cement. At

th e

same

time

chemical

action

ceases.

Even

though

the

cement

may

thaw ou t

later allOWing the chemical action

to recommence

th e

hardening takes

p lace in

a

disrupted

concrete which

is inevitably

much weaker.

During the

initial

set of

high

Alumina cement considerable heat

is generated increasing

th e

temper

ature

of the slurry.

In the

case of

a reasonably rich

mix

and appre

ciable

bulk

of slurry sufficient heat

is generated to p revent

th e

cement

10 0

0

1382

10

1.5 0

1399

10

3.0

0

1742

10

3.0

4

1286

10

3.0 8

1087

10

3.0

12

632

20 0

0

1764

20

1.5 0

1473

20

3.0 0

1490

30

0

0

2200

30

1.5

0

1815

30

3.0

0

1875

40

0

0

5206

40

1.5

0

2679

40

3.0

0

2953

40

3.0

4

1667

40

3.0

8

1173

40

3.0

12

896

24

24

24

24

24

24

24

24

24

24

24

24

I t

was

concluded

that

this method

of

heating

cement

slur ries in low

temperature

holes, is ess entially

simple and

successful. Although

practically no expensive supplemen.

tary

equipment is required

th e bulk

of

the

chemicals required

fo r

this

process makes the

method

imprac

tical in remote locations.

TABLE VI.

Oompressive

Strengths

of

High

Alumina

ements

Curinp Temp.

Oomvr. Strength

Time-Hrs_

OF Salt

el

Average

ps i

72

72

72

72

72

72

at

th e

time

of

cementing

and at

v ari ous time intervals thereafter.

Figure 12 shows a similar jo b con

ducted

through

1500 ft . of 4 -inch

pipe.

These tes ts

indicated

that

due

to

the heating effect of the injected

chemicals the cement should have

a compressive

strength

of at least

500 psi, within 4 to 5 hours time.

TABLE V

Thickening

Times

o f H ig h

Alumina

Cements

High Alumina -

Neat

1 hr .

40

min.

High Alumina -

1.5

NaCI

4

hr .

10min.

High Alumina -

3

NaCl 7

hr .

34 min.

High Alumina -

4

Gel

-

3 NaCI

2

hr .

2min.

High Alumina -

8 Gel -

3 NaCI

1 hr . 19 min.

High Alumina -

12 Gel

- 3 NaCl 3 hr .

35

min.

Based on t he se dat a an actual

cementing

treatment in

Southern

Alberta was performed utilizing

this te chnique. On this

job

7 feet

of

8

inch

diameter

cas ing was

set

using

15.6 lbs. pe r

gallon

slurry

containing 2 calcium

chloride

acce ler ator . Sur fa ce

temperature

was

26°F., wat er t empera tu re was

32°F.,

and

th e

slurry temperature

wa s

38°F.

Dur ing thi s

cementing

operation 700 lbs. of caustic was

mixed in 5 barrels of water and

neutralized with 200 gallons

of

28

hydrochloric acid. Two pump trucks

were used to pump these solutions

which

were

mixed

immediately

prior

to injection down

the

casing.

Figttre 11

shows

comparative

tem

perature surveys run

on

this

well

ti c

solution

was

prepared and pump·

ed down

th e

casing.

Even without

neutralization considerable benefi

cial

heating

of

th e

cement

slurry in

the annulus occurred.

TechnologYr Summer

962

algary

69


7/8

-

_

- .

-

_

...

o

·

J ~

_ e l t ~

SURFACE)

160

u..

0

VICAT

FINAL

UJ

a:::

SET

>

I

80

-

::

O l

a:::

.

.

•

. - .

UJ

a...

40

. -

UJ

I

TIME

HOURS

Figure

1 0 . ~ L a b o r a t o r y temperature tests

on

cement s lu rr ies dur ing

setting,

ut il izing chemical heating, in

sim

ulated format ion.

from freezing,

even

though

th e

tem

perature may be

many

degrees

below

th e

freezing point. This prop

erty of

high Alumina

cement slur

ries recommends

i t for

low tempera

ture use, in

spite

of its p remium

price. Ano th er a dv an ta ge o f

this

material

is that it enables consid

erable l ightening of th e

slurry,

a

definite

advantage

in

surface

pipe

cementing,

w ith resultant

lower

costs

pe r

cubic foot

of

slurry_

Various m ixture s of high Alum

i na cemen t s lu rr ie s wer e

laboratory

tested

at

40°F., th e borderline

tem

perature

fo r

normal

cements. The

cement,

additives,

water an d moulds

were

al l

precooled at

·10

F. fo r 2·

hours. Mixing an d poring proce

dures

wer e car ri ed out al controlled

temperatures of ·10 >F. The

resulls

of these tests ar e shown

in

Tn hI

IV.

Th e favorable results

of thesl

tests, which showed

adequatf

I

-.J

I .

I I A F T E R

\ • CEMENT

If

J

BEFORE

C E M E N T

O - - ~ ~ - I ~ - - . - - , - - - r - - - - ,

., •.-. ,

k

HRS_ LATER

I

r

.........

\

I

-

/ /

{ : .

vi

v Vf HRS

LATER

1 5 0 0 0 ; 5 ~ 0 ~ ~ 1 0 ~ 0 : 1 : : . 5 0

TEMPERA TURE _ OF

0 . . . .

---PRE-CEMENT

3 0 0 3 ~ 0 - - - - - - - - - - = 5 : : - 0 - - - - - - = 7 : : - 0 - - ~ 9 ; : - 0

- - ~ 1 l 0

TEMPERATURE

OF

>-

w

w

500

..

w

w

u

I

>-

0

W

200

:r:

0

0

W

Cl

1000

Figw e H.-Subsurface

temperature surveys

on a

well in

Southern

Alberta

following surface casing

cementing operat ions,

ut il izing chemical heating.

Figure 12.-Subsurface temperature surveys

on 1

well in Southern Alber ta following

casing

cement

in g ope ra ti ons, u ti li zi ng chemica l hea ti ng .

70

Journal of Canadian

Petroleum


8/8

Temperature

of cement

returns

No.1 42°

No.2

43

0

Temperature at top

of

cement

7 hours

after

plug down: 55°

Top

of

cement found to

be quite

hard.

TABLE

VII.

Surface Casing Cementing

Job Done on

Dome

al Winter

Harbour

No 1

September

30th,

1961.

Conductor pipe: 20 to 77'

Hole size: 7: 4

to 1048'

Casing size: 13 355

54,5Ib,

Outside temperature:

3°

above

zero

Wind:

N.N.W. at

12 m,p.h,

Temperature of

dry

cement:

8

0

Temperature

of

salt

water

gel: go

Temperature

of

mix

water

(lst 25 bbls.) :45

0

Temperature

o f remaining mix

water

(125

bbls.):

60

0

Started

mixing:

6:00

a.m.

September

30th,

1961

Temperature

of slurry

at mixing tub:

No.1 300 (Mix water at 45°)

No.2 40° (changing

temperature

of mix

water)

No.3 500 (mix

water at

60

0

)

No.4

50°

m ix

water

at

60

0

)

No.5

51

0

(mix water at 600)

End mixing: 8:00

a,m.

September

30th,

1961

Total

mix:

600

Ciment Fondu w/12 salt water

gel.

75

neat Ciment

Fondu

mixing

water:

Ocean

at 3 salt

Plug released:

8:08 a.m.

Plug

down: 8:30 a.m. Pumped by

rig

pump,

Temperature of mud returns while displacing plug.

No, 1 45

0

No.2 44°

No,

3 45

0

strength, resulted in s im ilar

tests

under more s tr ingent t empe ra tu re

conditions.

These

latter

t es ts were

conducted

at

temperatures as

low

as 10°F in an effort to

solve

th e

problems of extended

W.O.C. time

on normal

surface

cas ing j ob s

in

WesteTIl

Canada and in th e Perma-

frost

zones.

In

these

tests, aU

cem

ent, additives, moulds

and

cover

plates were

brought

to constant

temperature at

10°F.,

w ith the

ex

ception of the

mix

water whi ch was

maintained

at 40°F.

Tests were

mixed i n a Cold Room at

lOGF.

an d

placed

under

water

containing anti

freeze.

Thickening

t imes were de

t ermined by

AP I

Schedule I modi

fied

to

70°F,

an d

500

psi.

Th e

reo

sultant thickening

times

an d com

pressive strengths ar e

shown

in

Tables

V

an d

VI,

respectively.

The

d ata a re

no t

fully

developed

on

these tes ts due

to their severity

.

Many

samples

were spoiled by con

taminat ion with antifreeze. Sodium

chloride was used as

a

retarder

to

offset th e acceleration effect

of ben

tonite

on t he h igh Alumina

cement.

Thickening

t ime of 12 ge l

cement

at 70°F.

was onl y 12

minutes.

Based on

th e encouraging

results

obtained

dur in g t he se l abo ra to ry

tests,

a cementing

job util izing high

Alumina

cement slurry

was

per

formed . Deta ils

of this

treatment

are shown in Table

VII. In

spite

of

th e

extremely

r igorous temper

ature

conditions

under which this

cementing

t reatment was conduct

ed,

the job

proved

highly

success

ful

CONCLUSIONS

Evaluation of laboratory tests

an d

field

cementing

treatments

in

dicates

that

in most cases surface

cas ing can be successfully an d sec

urely cemented, even

a t extremely

low

temperatures.

Apparently. i f

th e mixing water

can

be

hea ted to

a temperature

of

70 to 80

o

F. , th e

additional heat of

hydration

of th e

h igh Alumina cemen t

will

prevent

freezing from

occurring

before th e

final

set.

Additional modification

an d

improvement o f

heating tech

niques should a ssur e the successful

performance

of

surface casing cem

enting jobs, even

under

rigorous

low

temperature

conditions.

Low Temperatur Cementing

Documents

Transcript of Low Temperatur Cementing