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THE SUG R MILL ROLLER

Bv R. I .

G E O K G E mu _I M. REXI)

Introduction

When one takes a visitor through a sugar mill for the first lime,

that visitor always seerns rnost iinpressed by the sugar mill rollers them-

selves and their artion in squeezing t11e juice from the

cane.

The object

of

this paper is to bring together a few notes ancl observations on

sugzar

Inill rollers it does not profess

to

be a treatise on inill design and. only

touches lightly on t he various coilteritiol~s points in connection with

crushing generally.

Fig. I T h e drawings for

sm ll

t p roller.

lllc largest rollers used

in

the xvorld appear

to

be 84 jn .

long

and

92 to

44

in. in diameter. Messrs. hlirrlecs 1Ya.tsun many Fears ago

manufactured mill with rollers

BB

in.

l o ~ g

xlt

i t seerns

to

be

generally

agreed tlrat the cconorr~ic imit

is 8 n.

I n the Ql~eensk~udndus4.r~he

srnallcst rollers are fount1 at Rocky Point, and are 24 in . in diarneter

ancl 8 in. loi~gwith jourllals 9 in. in diameter and 12 in. long. The

largest rollers found here are in t l ~ e

in.

nlills, and their diameter is

approsirnately 8 in., while tlie journals are I9 in. in diarneter ancl.

26 in. long. Fhe weight

of

a top roller. \wit11 pinion for Rocky Point

is a.ppl-oxixnately 44 tons, and the weight of

a.n W

in.

roller with Ranges

and

pinion is ayproxir~~alely0 tons. Figure

I

shows a. Rocky h i n t



76 EIGHTEENTH CONFERENCE 95



95

E:GHTEENTH

ONFEREN E

roller

F i p r c

2

a n

84

in. roller,

whilst

Figure 3 shows photograph

of an 8 in. X 3H in. top roller complete lv l th pinion and flange.

I n

T a l h l are gil-en typical siz s of

w h a t

arc

regarded

as

standard

rollers.

TABLE

1

The

grooving in t h e

rollers

varies

widelv hut

the

commonest

pitch

is

3 grooves

in 2

in . , the

finest

being

3

grooves

to in and

t h e coarsest

pitch wit

h

which

we have Iiad

expcriencc

i s 4

in.

Longitudinal grooves

are

used to

assist in fwding

and deep juice

pooc es

are common

to

mist

in

ett tin the juice

a w v . A skctch of typical grooving is shown

in

Fig. 4.

Length

in.

Fig. 3 Illustrating

on

84 in. x 3 8 in. top roller.

I n Fic.

5 a

crimplrte

three

roller

tnill with

n. X 38

in. rollers

is il iwtratetl.

Diam eter In.

In the original designs t h e roller

and

Ranges

were cast solid of

cxst

iron

Sugar mill

engineers

wil l be vent

glad

that

th i s

type

of construc

tion died

011t

manv years ago and

one

mould

hate

to t h i n k

of having

to c rush

at modern rates

w i t h

such

equipment.

jaurnal dla. in.

9

10 12 13 15

12 15

15 16 I

8 22

17 IB 20 24

17 18 20 24

18 19

2 6 2 8

48

54

60

66

7

78

84

24 26

26 28

30-32

32 34

3 4 - 3 6

34 37

3 8 4



78 EIGHTEENTH CONFERENCE 95

The

Shaft

The general construction of sugar mill rollers is well-known to all

mill engineers and standa.rd practice is to fit a cast iron shell to a steel

shaft. In the earlier days all shafts were imported but for a long while

now almost the wllole

of

the shafts have been of ilustr;llian manufacture

and conform to specification R S S 29/1941 2 8 3 2 tons tensile 2w25

per cent. elongation. Consideration has frequently been given to the

use ol a steel of higlrer tensile strength but it has alvraj~sbeen decided

that as well as getting increased strength there were bad disaclvarltages

in other directions and the above specification has come to be accepted

as the best all round one for roller shafts. Roller shafts are forgecl from

cast steel ingots and are among the biggest forgin~surned out

in

quantity

by the Australian forge mqsters. I t is usual for the forge to supply a

plain forging of rough cylinclrica.1 shape and this is machined by the

Fig. 4 Showing typicol grooving.

manufacturer of the roller to the finished size.

Top roller shafts have a

square at the pinion end for driving and all shafts have a pinion seating

outside the driving end journal. I n a number of cases a pirltle is

providecl at the other end of the shaft for driving the carrier or other

seconclary machinery. The sizes of typical journals are given in Table

I

and it is n~clst mportant to have a generous radius a t the fillet of the

journal. This radius must depend to some extent on the relation between

the diameters of the journal and the body of the shaft but a good size

fillet for a 7 2 in. roller would be in. and for an .84 in. roller in.

This will be referred to later in connection with shaft failures. The finish

on the journals is turned only and ground surfacxs have not been founcl

necessary. The body of the shaft contains the sllell seatings and these

consist of either two or thrcc seatings in the smaller size rollers and of

three seatings in the

7 8

and 84 in. rollers.

U p till recently it was

sta.ndard practice to key the roller to the shaft but the number of keys



95

ZiGHTEENTH

CONFERENCE 9

II:E

stcatlily ~lecrcased

~tntil

he

latest

practice

is

to

shrink

t h e

shcll

t o

the shaft

ancl to rlisprnsc with keysaltnyrthcr.

In these kcyl~ss

nllers

tlir shell IS dcsi~nerl r it on thrcc continuous steppd

scatings

ant

tlir

mannfacturers

aim

at

l

lit

the

ft1I1

length

of

the

n)llrr shell.

Pro-

v i r l i n ~ lre workmanship is first class keylrss rollcn

s l ~ o ~ ~ l c l

re quite

wtiqfartory, l ~ t t t s cssctitial for tlie fit Iwtivren shell and shaft

to

he

really

good.

I t

is \,cry

rlifficnlt

to

se l

t h ~

e ~val;s r)rolwrly ant

thew

Ii;11-c alwn .s lwcn W P ; ~ p n ~ t s

l ~

e~a rrls E~centry of jzrice

h r t w r v n

t h c shaft

a nd shcll.

Fig.

5 lllustmting

a

comp'lete

three

rol ler

mill

with

84

in.

x

38

in.

rollers

n

all

the older

d e s i q s the shaft

was Stteil at

thr

end of

th

shell

with a pair of split retitfninr: rings ccn ered a ful l ring, and these

were

desimed t o prevent r n t l \ r i s~movement

O

thc ~ i ~ e l ln the slraft.

For many -cars

this Company

has rccornmendetl the abolition of re ta ining

r i t i p anti has

turner1

out a large

urnh h r

of shells

\vitho~lt

rings

a largr?

number

of

rollerr;

have also h e m

rnnvertcd

to the ringless t 'pc. Again

providing the

workmanship is

g~lod here shoulrl l-lc n o tso~rhle.and

w i t h tkc very

large number in

service

i t

can

safely he claimed that

r ~ t a i n i n g

inqs

a r c a h s o l ~ ~ t e l ynnecessary ~nstr ia~

s

cntlwi rr

location

q concrrned.

In one dcsign a solid ring is shnink on

t t h r

shaf t , hut:

tl-liq is rised

for

attxrhtng thr j~ricering

and has

nntlling to

do

with

c~ldrvise

locat

inn.

The Shell.

Thc

she11

i s of c st iron and

metaIlurgicaEly must

he

of

an open

testztre

giving t h e masimum mip

on

the

canc and

t h e minimum

of

surface polish in^ in servirc. X11 roller rnanufactt ircrs have tthrtr otvn

rt

formulae,

but in practire

t

lvonld

be

safe

to

state

that

all

reputable



8

EIGHTEENTH

CONFERENCE 195 1

rnakem turn

out shells of good quality in

this

regard.

Tt is

deqirahle

tn s tr ike a haIance h c t t v e ~ n h e oppn t e s tu rc fo r ~ o o d ecdiny and a t

t 1 1 ~ i~n~ci mr

to retain

sa f ic i rn t

t

rengtti to prrvrnt r r ~ ~ n l h l i r r q~ f hr

i ron .

Th? method

of

casting

shells

varies

in

different

foundr ies and

s i n r ~ he shell IS

a

largc hravy-section

cas t ing , it

i 4 most i rnpnrtant t r l

e n s u m good fcctiing

in

order to prcvcnt undtlc porosity ancl t h e

inrmatinn

of

s l i r i ~ ~ k a ~ eavities.

lf

the shell

i

t o l* keyed it is g~n cr ;? l ly r~rel l

out ovcrsire Ix twccn seating5 and t h i 5

facilitates borinr.

The shell is

shrunk

t o t h c sh;tft anrl

s o m p m ak ers usp a pure s h n l l k n l e t h m l ant1

other makers a cornl~inntion nf shr ink

a n d

h y d r a ~ ~ l i c

ressinq.

Thi.:

Cnll>any

prefers the pure sh r ink method since it g i v ~ s c crta in a m oun t

of i i~ t r r lo rk ln g e twem

t h e m;irhinc marks on

4ir-lI

and shaft and gives

s e c~ i rc n d 1 r . i ~ ~ncation. Thc I\l;lchines~.Hantll>ook

st

atrs

: e s t s

to

drterrninc the diffcrmcr in quality

nf

shrrnkag r mid

l o r r ~

ts

showc(l

t h a t

th e

rtsi4t;tnrc

of

L

chrinkagr

t i t

to

~Iippi1y~

as for an axial pu)l

:<.tit;

t imes

~rcatrr

Iian

tF~;.t

of

I

lnrrc l i t , ;lnd

in

mta t in n

nr

t o r ~ i i ~ ~ i

3.2 t imes grra tcr . I n

car11

cnlnpara t i r c test

thc

dirncnsions anrl aIln\v-

ancrs tverc. t h e samc. I t

r;lru~rlt

k+crlainred, ho\r.cvrr, tha t

t l~erc

h;i<

l ~ c c n

arry ~~ot i i . cx l ) l rmul, le wl~irhco~ilrl

w

trarecl tn t11r tYSrt i~tf trf

f it ting the shc ll . T l ~ c hcll

i

mac-liinetl all o\+crand .

as

statrrl in

tllc

preccdinq p : ~ r n g r a p l ~ .s hclcl t n tlw < ]aft cithrr l>\. thc sIirink n l u n r or

witlr key ; I t s h o ~ i l d $Earn \:P rmplra<ise:l t h a t t h e fit Ix t~ v r en ;h aft

xnrl

~Erlltt the

mds of

tlir

4 1 ~ l l

4 vrr I+1rnport:~nt an d

i t

r lio~tltl nl

w

pnssillle

tl*

i11vrf

t h e

t f ~ i ~ i ~ i e ~ t

eeler

an vw hr rr i~rolinrl he pn(l<

c j f

t l w

.;hrll.

Service

Conditions.

In ~ r r i . i r r ,

I

roller 1s z l i l> j~ s t o ver \* 1 .11nsi~l~i-a l11~t r~ss1111 ln

; t t ~

X4 i r i mill

thc total

hvtlra~tlic nntl

on

t l ~ c

wo

journals is 500 700 on.;.

l llis Io:itl i s oc-r-;~sionrll

;I

rini lormly tfis tril >r ~te t\ rrsl;urc dltr t

n

t hc

I ; I K ; L ~ ~ : r t \ r e n tlw t h r r c rollrrs

anr l

thc rolrrr ran

Ilr:

rccartlcd a<

:L

r r ~ m ~ ~ r~ ~ n r l.r :~r~ir\lnllt.lslilc t lie .;hell ant1

<hilit

conihtnccl. That

1

~ r h y

i t I <

so

1nlpclrl:Lnt

t <

II;L~-r l i t ; t t t t ~ cnrl ; n l

t l ip

~ l ~ e l lp ;~ r t i ru l :~ r l \ .

goor

orw

.:incr

1 f

therr.

is

;rnv

m rn+rm pn t

l c t t v w n

sha f t

1t1111

sI~ t l ,

l i ~

s l rnl t r l r f l ~ r t i o n wilI inr-react ant1 \<?hen tI~c rdlcr turn4 tills ~lctlcct~nn

r n t l k cq

R

t * ~ n t i t i t ~ n ~ l sCVC~L:I I

of

<tre<sc< wllirll tTliLi+ c a s i l ~ .

;111-r

tl11-

fraf. tur?

o l

t11p

s h : ~ l t .

7 11~ S ~ ~ S S -{uirt-.-Fr(vn~ ol)rcr\+;itons of a very

large

n i ~ n ~ l . c rf

rclllers sent in for re-sl~ellirly it

i s sur-prisinq

In how

man\- rasc

thcrc

art=

rlistlnrt c i e n ~ f ingrrw

of

juice fnr snmf

distance Ix-twwn

t l ~ e

hiift

a n d tFie C I I ~of the shrll . I f tIlr shcI1

is

r ~ g h tdown

on

thc 4h;lft t t ir

hard t o

see hnrv t h i s

jr~ir-c :in

g ~ t

n and t h r

fat-t t h a t

juir-r rorrosi t~n

wrnir

SO

pvidmt

wo r~ltl ntlirate th at ther e h;t4

l ~ c c n

l

harl

fit

from tlnw

of m a n i ~ f ; t ~ * t u r r .

11

those d iaf ts t r~hichhat1

Iwcn

forcer1 i n t o t h r s l ~ r l l

the

juice may tend

t n

u*nrlr xFnng thc scorcs

cnt

in

ttir

shaf t . I<cv< ;Lrta

also

a

~veakness in this direction as thc ra i~ lk in y s strir* tly local :inrl

is rlnt r f icct ivc for any

len,@h

or tirnc-.

R y ;E c*oincitIcnrc it

lias

l r r n

O F I T o b s r r ~ a t i n n h a t

t h e 1r-or5t

sign5 of juice

ingress

arc on ro1lcr.q frttrcl

\r,itli

cnd

retaining rinys. Tliis ~ ) r o l ~ a h l ylar 11otZ1ing t o rlo with t l ~ r

ring as

such ,

I ~ u t~t is fclt that t he rnanufar t r~ rc rsmay haire rclicd too

mud1 on thc rlng ancl

keys

and

Ilnl-e no t

hccn

ca re l r~ l nough i v ~ t h

Ilc

tit at the end

of the

shaft. I t has also bcen m o ~ t nt~ceahle hat n largc

n u mb er

of

Incipient

cracks

in rnller

shafts

take

plare

at

th e

retainir~tr



1951 EIGHTEENTH CONFERENCE

ring

grooves

and

as

t h i s

is

thc w eakest p i n t

of

t h e

shaft nne could

e s p c t

cracks to s t a r t them. Providing t h e

shell

i t s properlv on th

cntl

scatings

t h e r e does

not

seem to be

a n y

need

for

a

cen t re sc,~tfng. n

other t h a n thc largest rollers and prol>nlllv not

even on

them, since

although

thc

ccntrc

of

the

rollrr

is

certainly

t h e

point

of

grcatcst

strcqs

t l l r

combined roller ant1 shaf t

seem

t o

have

amp l e

strenyth a d casec

nf

rollcrs breakin4

in the

tntticlle

are

very

inf requent .

Tht. RrefiLiny

o

Shnfts. The top roller shaft

is subjec t

to t he

crca tcs t s t rms, since

it

ha s to transmit the

full

torsional load from t l ~ r

rrrgine ant1 also t ake t h e full bentlinz Ioad from t he crushin: action.

Thcrc dors

not

hotvevrr,

scem

to x a n y cuirlcnce of a g r ra t cr n u m l x s

of fractures in t o p shafts than side rollers sliaftr;; this may be clue tn

thc f.rpt that in most mills the qhnfts R e

chanqed

arolrnd

and

when a

shaft

cracks

it

i ;

.cry diflicult to say

just

Flow long it

ha5

lwen

i n

any

pzr ti cu la r ps i t i on . Sometimes mills hnvc broken l rand

IICW

s h a f t s

aar

l

I +

very

I~arcl

o

account for the failure.

T h e sz~bjectnf brnkcn rollcr shaf t s has tc:eivcd

arcat discussion a t

~ r r v i o u s

oniercnccs

without an ;

d e f i n i t ~ cason fnund

for their fRII ures.

t is fel t that with

a

shaft of good drsiqn

under

normal work in^ con

rlitions, failure

takes

p1;lc.e only af tc r

a

rr:aionalsle life, and

faiIurc

must

hc cxpctcd in rlne rourse from such

;L

h i ~ h l y tre.;?erl component.

I ' i-~~bahly o sugar

company

ha s suficientEv acruratc records

of

i t s shaf t s

t o

I I

ahlc

to ind ica te

what

t hc

life

of

a

shnft

should

hr:

an d

i t

is

expected

that th is l i fe coulcl l ~ eelated tu ton-hours i f sufficient information were

;ti.ailaI~lc. I t would posqil~ly c found t h en t h a t after

a

ccr ta in nurnbcr

nf

ton- l ln t~ss

~t

wo~iltl dcsiral,lc

to

scrap the shaf t .

Speakers

a t

prcvious Confcrenccs

h a w stresscd t h c

dcsirahility of

x

grncnlus

fillet between t h e

journal ancl

t h e

h c l v

of t he shaf t

and

have

fclt that hrcakaye of shaf ts

would be

encnurayed a t t h e

fillet

if

t h i s

hc

lnade

too

small.

t

would

sccrn

hnwcvrr , tha t most I3rcnka:cs

t a k e

plarr at t h e end of t h e

shell

; th i s indicates that t h e t>reakaaes due to

rhvcrloading

of

t h e ro l k r and shaft

assemhly

and

that the 1r:icttire then

t a k e s placr:

at

t h ~vcakcst point

which

is a t the end of t h e shell. I t

II IS ;ll.io

k e n

s u g ~ e s t e dhat

when a

mill jam4 a n d t h e c u ~ i n es

reversed

the

energy af t h c flvwheel

is

dissipated

rreq+ apidly in to the choked

mill

and

t h a t tb.c CICCSS~ I ~P torsinn

causes

the rollcr shaft

to

twist

off.

Again

~t

iq hard t o collect

snflicicnt evidence to

indicate that the

cr~mrnonest

point

of

fai lure is thc r l t i v i n~end

of t h e

top roller

shaft.

as wnultl

be

t h c

cnsc ~f

th is

theory were

t o

Iw

lxlrnc

out

in

practice.

I t

is

n n t ,

however t h e

pnqwqc of

th i s

paper to

discuss t h e m a t t e r of

9ll;tlt failnres

in any

dctail .

RC-sltcllin~.-:It

one t ime

it was consiclcrcrl untlrsimble to re-shell

rollers anti t h e

complete

roller was scrapped as soon

as

the shell

hacl

r v r m down. LJndcr pwsent cond i t~ons .however,

shafts

are P-shelled

a

number of t imes

a n d

no information

is

avai lable as tn t h e n ~ r r n h c rof

tlmec the shaft wirl

stand

re-shelling. In the re-shelling process ccrtain

repalm are usual

and

badly worn ~ o u r n a l s

an be

Guilt up

by

electric

ivclding tn thrir original d~arneter.

This

Companv has t reated

a

large

number of

journals in t is way and there has tmcn no single iwtancc

of

failure

which ran he tracecl to i t . .as much as in . has h e n b u ~ l t

111)

fin

cach side

making

a

total

increasc

in

diameter

of

1

in.

\Ye

also



8 EIGHTEENTH CONFERENCE

95

frequently fill keyways so that the finished re-shell has only two keys in

hne instead of four keys at right angles as it may have had originally

Observations on

Mill

Practice

Under operating co~~ditionst is usual for mills tn spot the

surfaces of their rollers to increase their gripping powers, hut the practice

in this regard varies very widely; some rnills do not spot a t all while

others spot more than once a week.

The object of sugar mill rollers is of course to extract the ~ n as i rnu n~

of juice from the fibre and the whole of ~niiling ractice depends on this

;

sugar lost in the crushing process cannot be recovered anywhere else in

the factory. I t is of course necessary for mills to co~nprolnise etween

crushing rate and extraction unless the- are fortunate enough

t

have

crushing plant sufficiently large to

be

able to aim at the maximilnl of

c s t r a c t i o ~ ~nd also maintain thcir desired rate . There ~ n us t lso be

a

point beyond which it is not economical tcl carry the extraction and

it is also claimed that

bj.

taking extraction too far, some undesirable

ingredients arc forced into the juice from the fibre.

I t is not the purpose

of th is paper to deal with milling practice

and

brief mention is nlacle

of only few points in connection with it.

The crushing action derives its power from thc engine through the

gearing.

I t

is obvious that the rnore po\\-er cscrted between the rollers

tl~ernsel~.eshe better and inore coniplete the cruslii~~gction will he

I t is not suificiently stressed howex-er th at it is the ~nil lwhich initiates

the loading for the engine ancl thc nt~ject of ~rlilli~igractice slloulrl

therefore be to get sufficient load a t tlic rr?ill to ;~lxo~-i>he full available

horsc po\vrr at the engine end. Tn verj. man - mills th e engi~ies re ~ i o t

working up to anything like their ma~iniuin .H.P., and it ivould seen1

to serve

110

object to cnnsidcr reylaci~ig- he engines 1 ~ 1 t harger tnles

ilntil the existing engines are working a:, hard as: they can.

Two general methods

of

milling arc in

use

The first is to rut1 the

rollers at

a

high surface speed with a thin nlat of c.anc, ii~iti he second

is to run the rollers at

a

slow surface speerl nitil

a

tliii,k Inat trf c an e

In between these extremes are numerous combinatio~ls. I t i usual to

think in terms of sl~rface peed, kilt in practice U\-erseasa11ti here, surface

speeds vary from

10

to 40 feet per m~nnte.

t is also usual to generalise on gearing ratios anil the t e ~ l d e n ~ yas

keen for gca~~i~igatios to be reduced in the older mills ratios bvcrc

a.;

high as li to 1 while in solne of t hc newer nlills ratioi are as low as

17

to

1

The writers feel tha t gearir~g atio is a sccondar\* niattcr and

that it should be made to suit the op ti mu~n ngine speecl and the crptinlii~n

~nilling peed. 1YitI1 an engine speed of, .;a -,

55

r.p.ln.. and

a

gearing

ratio of PO to 1 th e s~lr face peed of a

38

in. roller is

2 i 3

ieet per minute

ancl that of a 3 in. roller is 23 feet per minute. This shows tha t as a

roller w a r s the engine speed must he increased if it is desirecl to ~na in ta in

the same surface speed throughout the life of the rollers.

I n

the case

stated above it \vould be necessary to increase the engine speed to about

66 r.p.m. in order to maintain a surface speetl of 7 feet per ~ninutc

after the 38 in. roller had worn down to :E n. The hgures sta ted

are

not reconirnendations

a nd

are merely quoted as

an

example. JIills of



1951

IGHT NTH

CONFERENCE 8

3

course

wish

t use their rollers do~vr-n o as small a dialneter

as

possible

and the ~llinirnunl ize depe~ lds n the design of tlie roller and o n the

wtting rcquiwd for good c.~pcratiull.

If

there is some surface sl,ecd which

\riIl give i l ~ e est results the ubjec:tive of the origi~laldcsign should

be

t o

lis

the surface

speed

and the engine speed and then provide

a.

gearing

r a t i o

to link those spceds togctller. The modern tendency seer115

to

be

to incrcasc gearing ratios again and therefore reduce roller s~wcds nd

to

\vork on the

slow

speed thick mat methotl. I t seems that this s h o u l d

,:i\.c greatly decreased slip and strould thercforc allow

a

~ l n ~ r hreater

j>rol>ostionof the engine pourer ttr be used bct\vee~l he I-ollcrs, whereas

a

large p~-oportionmay otherwise be wasted in slip. It should

also

~.e.;ult in reduced roller wear and should remo~-e ome of the riei-cssity

for sl~o ttirlg

Conclusion

Kollers

X

i n . in lengtll seeln to 1 e tlic tna si~ll u~ill l

worltl

practicr,

b11t they Itlay l ~ e

2

to

44

in. in tl in~neter nd no do111,t before lung there

u.111 11e c\.cn larger nlills in Xustralix than there arc

a t

present.

he

o\-t~r-sexs endency also seems to he tc~wardsa large ilulrlher of rollers

i n

the train ;lnd where the maj on ty of Queensland mills ha\-c o~ll . twelve

~rollers, ornbinatio~isof up to

22

rollers are quite usual overseas.

There

alrcadj- secrns t o be

a

tendenc ; ht re towards

a

combination of rollers

~rlaliing

15

in the train and the 111i11s 11sing this 1net110d ill sccnl

to

be

X-cr\. )lea.;cd it-it11

the

s e s ~ ~ l t she - are getting.

111 r-o~~clusiont is clcsiretl to repeat the fact tlrat this is not

a

tcchl~iral reatise on roller design or milling, but has

jus t

t ~ e c ~ lritten

1 clra\v attention to that most useful cornponetlt- the s ~ ~ n r

nill rollcv

T11r 1 3 1 f i ~ d z t 1 r ~ g

o ~ ~ u d r ~

o. 1 td

I : I I I I ~ N ~ E Y O .

sugar mill

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