BSTJ 10: 1. January 1931: Paragutta, A New Insulating Material for Submarine Cables. (Kemp, A.R.)

7.3 MB·English

Paraguéta, A New Insulating Material for Submarine
Cables*

see ean nb ng pe cot al te
TE hg lel cal ieencacensgn ar eh
pac per dees «ce amici lied paracuis lac be been

sath eel ete atm oh
nae eh sf te dae her

citi eal propa ual eri Wi Sete
Se indies ot Genie fate See es ag
‘sli oage te Sams tebe ate cele

FosmERLY ae
Prurpoces bu: in nt stare Chee 4s Leen an emer eof
Chis type e cable for tlephene service. Telepherse conumznication
Fecuine vibes of very anuch sxpecor teeaamision quality 10 ‘at
reece for relegrayh. AL Toe higher iroqueneies of vate tsa ieson
the enssgy lores in the inculetiag marrial become & serious factor
uns radical improvement in subm-rine insulation is called fs

‘The longest exiting des cea cables operating et voice Lrequeney
‘only sigtly exceed 100 miles the wonton of transoceanc
telephone able ich standard musteriay haw been repartee beyond
the poaeticol Himies of feast

‘he installation ad sapid expansion eransatiaatirado telephoay
daring the pat few vears have created @aeed far «deep sea telephone
table to supplesreat this eerere, parienloriy diving periods of at
‘nosplerie distasbanees, In eliition the uevelepment of carier
feleohory offers yrasitiltigs for increasing the trate over shovter
submarine cles, For te shrter eable, the still highee frequencies
Sr carer telephony make emnes upon the insulating maceral
Sil o those of long erbles operating st wove Feawencr

Ts view of thewe cierametances ny extended stuly was undertalzen
of che entsee of lowes and eter eletical weakness of subinerine
insulation ard a seacch ee boon ade tor becece matece'e. AS

wr. Fowin Posty Jn 198

dns sen ual wxrsivey for telegreply
resale of hig investigation an imlation called paragntta bax bean
feveloped waich, as the mane sigaeet, i derived essentially from
rubber ad gutta pesca, Tis tre pupa of I's paper to describe
this materi nd jéve an aroun of che teste lo which tas bees stule
jected to deterring its suitability for the puree

Hy vine af ts -upecior elgetrca properties, Ie ase of parsgutta
ins pull pertia for che ioulaon of telphoue and tego
sbi offers omlayges eller vem che steadpoine of improved Teate=
Inisson or the economies in mateciela of coaserction thick cin be
mace aea rest of mocfed cenga

(Gutta preha se blak lve een te standard mevertals for the
insulation of deep aex exblen xine Te inerptian of the subaserine
cable indsry sone eeventy-ive wears seo, AlRhiadh ese sub-
Fanoce are inadequate for modern teephvine needs ae regards Tie
Slcleal cheretavatee, thelr mechnieal properties are peruar'y
fnapteltnsabvnasioe ingalstion, This i mar ee eave dea gua
Pesca can Wily be taker ass svmle which snus be closely ined
J respect to mechariea chau eens hy aay suceeasal sueticte,
‘Thies tartunate since fe oe of any aubstitute whic: dittrs rail
fom gutta pertha rut wean diccarding Large eetng investres
in epecal tecknicue, eqitment el tained) peronael, ane wold
involve serous rieks ex tothe inlegrty uf ables male wits Uke new
snarelia Tt muy be rimarkell passing thae bo siaoweacturing
Srocess wren ger eye susan against eceniona fects
than cies tie submatiaeiuslation ara tact chat has engendered a
‘vou coaeecvaciam in ye indy

eccase of it lest ea ne sneal popestos, Us requirements
foc submarire calle insulation may catvenieatly be deere hy
reererin to gutta peel, Gutea persia insulation, whieh ofits
Includes more or lr ala init coanpeitio, is made of raw materiale
farfully selected for-qualicy, which ace trorsughly wie’ ane
fstrenly uniiealy Lenéed, “The theemoplneiciy a te wateral
ju gecat seivizo-n chose operations amd further peemia it to. be
Fadi extra cme tamclite> in oultipe layers in a comeracas
sheath with gre esssineas and Leesdom trom mecssaieal detec.
‘fier beng forced around she eonduecoe the mturial qiiekly 2ets O

acy brag envesing wen doawa ehoura cold wacer, Ie rns
cr coughs essen a cet subsequent handling eperacions ia
the factory 2 well a chose involved in layiny, pieximg ny andl ve
picng. The worm, aofe wacerial adheres readily co the coelartor
{ind wll alaptel to tke mang of ont inthe insula un Letweca
{ore lengths bath in che sary aed om te able i.
In addition Uae exoslest sad unique mcchsuical properti,
gutta percha pssst let real sharaeterstiespaciaely aaa fo
Eubmiatine exble consrartin, ox onntancing electric! merit com
sta in the Sack shat its cleewcal characteristics are stable under goa
botom eunditiogs over a reat many yan

(Gurea pera sober leh Taege amber of eyes
of tres growing wil in Use ireate of the Malay Peninouls tl the
net Trdan Tslwd. The produc ofthe various species of wees are
by ao means of ex walt, varying a8 they so fo the cent
Iyrocacbon, wens, sicdsluré aud wiliereulitauces, Since the ma:
{eral is gather sul wns ka up span the spn hy paiantive pane
peat deal ofeaelsonse ns wl ian allan ypc?
find he material cones upon the wasket in a icky coudtion au in

ng variety of forme whch almost prokibi fective inspectics
slerliation aud geedins.

“The esseatal coartivuent of gutta perches it an uncacirsted hydro-
abou of called ntane wich ix si ar inf ceriny terrae
i this coastisucat which males guits yet plastic when we
tnd tougs when ele and which conisblae east eanapionoueiy
Fae electrical exellence s+ an inealate. Te sual gull percha fe
fultion isthe real of bleFng al wing various grain of ere
fret pores Up remnve dire and wae eoluble components. Tae
‘pdr, resin disk and sinistare ceateets ae detscmined Ty
analyvivot neerule mstesaltogetber with the electrical end mecan-
ies: pronertin after wasting are che principal characteristics wed
fleceemine whether or nce a particular zrade of ered quea perc is
‘ule Tr wat ae auhsasine cable ination, The hydrocarbon cone
tea of gutta petehsinatiation when appl (hermes easy
bout 20 pes cen the reine ing uly the waar erin co
Seiher with emul amounes ef very Analy elvided diet Chuamus) and
esd) moisture. "The praveins or alluzeaa in crude gut percla
lind baleen ave alu! cuulaely removed lay spe wang.

alata comes rus uso eperea ct ereca of che same general Botanical

‘anily ae gutta peccha. bus = native t the foreetreeloas ef upper
Sout” Avries ard ‘e tokvowa in the xutta percha producing
fof the Kaz Eeat, The latex of sho baat tm bre Holt tha
ff guua percha, whick pezmies che tee to be toyed and cb uid ©
‘ve eallected ata centel paint in she forest, where the product from
‘rious toe vel fur sven of he gut Because of the all
Tumnber 3f cen valve and I trap tebility of re il Fey
Dalste ie vroducel in a uch wre Tiled suber of grades and
‘leer mul rn Cpenable ato weovmiey of quality, Its essed
consttuecs is the sim Tydnasthins lis gutta geisha, eons
In addition te the bydriearin, Were > prena fa Tala-a sowie 49
pee een ot zeae ued ci sf ry wokacure and hey fap
whieh uauetly coral about 15 pereent. ‘The reine uf alta ares
ton chow of gata poicha ane ate t3e poniuc: Sa ice raw etate a
Jil lea estate thap the better geedee of gutte perehe from she
tnivhanial sleadjoins, Unlsta, Lowever, coxtine x amelie ameant
Sl finely diicee dite or hums char gueea perch, whies is eelecied
In ee stpiron eheirvan ghrvoc eis sal Ine wala alwenptin

“Le resine cf bet:
acho in-making submarine inulation, Suelo, boweves,
Portcn ofthe resize are remuvs party iweease cas ough
teily Uo improve the electeal czarzcerists.

“There ave wersl mills whith may he used for propaing tea
hydeuririon neory fiee iin rsiaous subetencea, ae of
sathode involves disolving the Sslata or gutta percha Ss. warr
Detroleustnapacha, Scering the swalion roe diet sea presi
The ttn blocae on Ens ution Wy ebsigeration,Jeaving sos of
themesnais wslulon. 2 aimpler and less expensive sae:hed, however
fs Pua of lewhig wut dhe sine “yy sisply scaking she ahectod or
Fly ct satesal isa nableprade ef peteoleur: azpbrhaatrdinary

iquime have be ay fll wil he Wyre

temperature love by sexing of tse sclutn vexing aul Gn Sp
‘evaporacing the residual wlvent fom che exteueved materia
Tre complscly thrall Fystnwaran Ion oles srs

table forte sine: nubs: ine cae faletion eetsoe ia
ently plate ot anfe mocking weanpceariies, 24 well sm pedi ely
pensive. Dtherwine te tunplote devesination of These prolucta
peu be highly salyaotageour aa, Ine eaanpy ica hy die
voting eleccrieel chazeowtriedee ct devesneted Galata abewa. ip
Table A suintanial atzount of expericcctetion upoa the mechcds
cf rotinng Volts as been soccese-y to ever che exoelent eeteeal
‘Guaracerstierthecen jncioned bu? ao revolutionary iagcvation ba
Tooen nse

Tas ccbesting ove 4 new claking anevada Cop wen
cebleg ir soured best to begin wich gutta Hytrucnsben, ea Basa,
tizoe its meebsciral pmpertes are so unique rather than to sttemp:
tn eyothesie a new Chere cured which null instate it. by
der ts eveensine che excessive tifiess of the pure gutta bydecs:2on,
fe well ee prohibitive ti we llere fae! Lo alleant to blend
Taupe quantities of rubber wit 31, fuer vabtier ie the neavest kinded
‘materiel and ie commercially cvailahie at low cost. "There cessed
‘hermes preacls fairly pod aechanice!ebarscteritics which,
Laorever, proved i be ivaiaicndy stable clecuiealy

‘Meanie, a thorough acid wie Being mss of the clea sed
physio eharacivaties of suber and particul-ly of the cavers offs
Cctrcal instability coon paged immersion ia water, One hepe
that euch a szndy would mot only eeveal che nature ef che deeces ef
rribler but ates aceges as for sesnscving thems has been cealized

ro sratfving Neer.

alas, ao well koway € alma toed rm the lace of esata
uses, chity Lae Bravtarels, “This dre tan hoes euliveto in
Tage aisan cu tae planvarione ix the Far aa. aud the product Se
Obiaaabie, commercially i evry aancecdined grades, te
principal consticnent is » hydeorarhon seesoly distinguisnable Seem
that ef ura percha by chemical wisn, ut cedieallydiderestSrer
iin phytow propertiny wulably ia thae it has but a eight degrer of
theemyiseticty ad is far nove distensble in the eld state. Asie
from the bydrovarbun, ruts alee contains erall arvwnta af eens,
ppmtcns nel other fire, But tae gem herald
‘Ghnalicventn nthe Ite giedes aze sully Teve tha 10 ger era
‘Gimraat ta SU per ctu or thesnbors for gutta peecks and belata

"Ruler is used almost exclusively jn jidusiry in a vuleanized foun,
tat yf eomabiation with a svaill yeramtage ef sulphur. 1a this
Tora sable has elzo bocn sel fr lige extent Sor aubmacine cube
:aulaton, but has leg ben reo guized as lacking sufilene elec
Sasiley for decp cea sulle Coigned to carry a Eeavy trafic. Tis
Sell rd to 2 vomsidecain ete wieh @ Sa rem of acces for
insucation on shir! sales ese the electric recfmninla ace not
severe, In croveal waters has the advantage over gutta pera ef
fate erstanee tn trea ace sid to latrage hy igh temperature

‘Sve years gna extended stds? wa mone uf ie cauace af the
cerlviod iombility of wuleani rubber, hich led to the conelusion
thar tae water aoluble impiriline are largely responsible. These
laxpusiticn com be cemoved samparalively seadily and sotisiactrihy
Jn the ptocces of mamafacture, and a subaucine ineuistinn of a fair
degre of silty iv Geely’ atained.
sven go. vulavid cubher is very flere ip quua pewha fo
substarie iu stion ae the neceseary manufsetnring operstins are
moe fie tae Hike oe toeketers.Thecenneal af tacanical
purities is by wana simple becuse the rie werk i wo plasie
‘ough fer eheroug slraning. ‘Ese lack of plasticity also interferes
till mulple covering ef conduetare, and the process uf heating to
Ting abeut vuleanizabiry iy able to result ia deferrtion of the
isulocice layers, ‘The jining and vepeiting of core lengths iulted
Sith bher fs asn ge af «peublem twill gut srl, which

‘be wo mally role ites imprints appese i he ree

fhe prowess,

Tre rethouls of slactdeal sitiietion of wuleasiatte rubber
sompesstions acl patiallyeXectivein the versa of yalesnizatin
sad it wae therefore nermaaey Lo extend che study ia an effet to
Sew the desired eleeriea properties im rubber in che new state,
Terigh be eupposrl that wane adaoxtate of raw robber wth gurte
syeroearboa will yrsuee se neesesney sabuity, hie true
ily ton mite extent, When che projortneu? euler me high
acvgh tn mee: The mechenice) rnd simone anicements, the
Hlvaical abi ia peice.

erocr oF Puorems 0 binermear. Seanmry ar Carne
Ramm: inuasoo re Warr

1c hae een prevesly shawn that erude ruber cotaine conie:
able water solabe impuctes and Ueet their removal reste in
Tage Teductice 'v weer onc? Rusher 40 prepasee aseorhs
tes stare water cha ou ele uta povchs but ima ran state whe
itmremicl inate file ecaner of lager aan fever, cea sie
erly enmplety

"To detruie se easou tor this elecrrcn! netaility of era uber
ler, sample of ver pave rlsberhytlorainn ently feed
From yenleive sins and other impacties were presieed sed vested
Tea Foun at Usig raced cot on'y abeanhee were ite ten

hue wimedponcically ao charge Selec earavteries #4
sult prolanged szamersion water. THe iuritien nated
INiobec tPerenvn stom te eeponaibe fer ie inet

Tr hay few krone for many wears tht crude suber contain
ruteinn, onfimsy qVesatien subber containing about § per cent
Previous fivestigators Rive postulalel aml sliogn omstien ble
ines evidsae ap he effect 22¥¢ che ralsbee globes in -ybber laces
Iruoe av aubon Td liao protcin around them aad that this eandtion

Lamy Kul be Cem 3,25 OME
ito egetein ere rubber. Tish kvuws that ete su otaina
fe aubstaacal quearity of protein insulation. Tlie precacatinn of
fide eubber from lex hy alifiion of se or iy proceses of evap-
‘vation of the water by hete unduly eta he precitalnn
‘Sr oonsicerabie quantities of ts rutin which lesen enlace
Tecwesn Ue gobaies ve they eaten, Te ie ey shen to vioualine
that ia emide rubber cher evaiy sv erainanis phase of prota ara
Denlein network which, seting Hike me poten mater tool large
{qasusiics of wer, eeleing in paths Gough which elactree! com
(actin ocury

uuoval oP NetRoons Conmansrve Bonus sou Reasa

“The prebie= of developing +1 suvable curmertal method for
vepaviig rubber Stee ora aeoenie tier ered many ayer
Aiiwaties. Te penteine aoe colloidal fe wey sed tthe preset

(sv wats fs gelatine snaees eather them crue solutions. Qe his
recy. olf canoe he removed by sinle wahiag wen done
fn the eaee of gutia percaa sted balan. 1! has lines lao Gir sean
fine haz proteine ean be broken Cow tx water alu predict y
Twilag wis elute Evdcochlosie er sslphuse acide. Tie westment
Se not prude win nelory vou ine case of 5her. Asa rosule
‘sf meny experiments invalving varely a! methoda, wes tound that
ating rubber in aq auloelaye at an elevared temperance fa the
rownee of rar lowe far'y vapid heouhe abot te dette y=
robe of He ruler protein converting ebem wo water soluble
imatevals. Aga tscie of eubeequent wihing, we fn’
Siirageoras bodies had hoes alunort completely eliminate! ithe
Hlelvernus eect on the rubber bydrocaton,

liber either in the torr of hurls immersed in wale or aga aque
ua cubes dipeceon such s Islex van lie ployed in the process,
the treatment of ste, however, rents in a tact repic lserolysia
ae protets,Covsilevalte Talituda exes in the chee of cundi-
tong, but the Following exaeaple wl sufice eo dece:be one metiod of
cacrying uur the proces: suuouia preseved tex i eile 1 rn §
tvith pure wo er The atic ie then Reaced in an autcctave for ayprne
Ficely gem hours al 180° Cfo cooling it is exalted with
suet ad aud Usicuagldy woeied x arent of #His teatment
ie aikngea content of tie ruber ie ful. to le “oe Uaan O10
er cei wil i abot one feurth that of ordinary plewlacon cues
fibler, Figures 1,2, 3 and silleteate tha relative waver absorption
Sand elected etabiity of leqmowinized cubher as compared with the
edinacy erie perde!. Vilkaniza! daproeinized rubber was also
found to be coment supesior to ondiancy wulennized ene user
as eezare le eletreal sabi in wate:

nadia te the soperiereletrca stability of feprotioizedsubher,
it was Touma to Ue anoce esdily plosticeed sal ieed wh gue

#

re aan th weer shart af ade

thn Sethe cate with erude suber, ebereby yielding a product with
hotter thermoplastic properties.
Pemraxeron oF PaRAccTTA

As previoaly stated, tie principal constituents of paragutts are
lieyroteinied rebber nd. purified gutta hydrocithen. Specially
‘eciter hydrosaitny or moatan waxes may alao be eded es» tied
couetiuant to modify mechanical properties and vaduce amet, The
Proportions of thee constituents aay be varied over a wie rng
Achieve the desved characteristics. but in geaeral rubber and guts

“Th

are ues in ue equal poyoctins atl purified noatan wits say be
fede! up to alias 40 per cent. Superior elevtiesl properties, how
fever, rele fom te use of hydroearhon waxes, which may be added
Jn amounts up to about 20 per eeat. By the proper blending of these
raterals, a thermeplastis inulation is obtained which closely ap-
frampites guts perc in meclvnies) properties nnd ie fully ia equal
* toekctsieal stability ia wate. Ite specie eletrcal characteristics
epsesext a substantia inpoveatene ower thos of the clase aaula
titm company and ita corti lower.

"The final spe ia procong poragulia ave very similar to ehese
nse far gutta pecha sad invalve Weuling aad washing the depre
lenin! suber sad cevesirated bala u> Rutt together, mastcaring
to remove exoesive water and st che seme tine incorporating suck
water a5 ace found nersary. The zaatssL i then straved through
Tine eves under kydvalie preesure <a remove adventitious impurities,
[Ewaed (remove aie and ally placed on the covering machine alls
tore ficted avcund the condariie. The machinery in use for pe

8

5

tet of wnting a err fying sa adv of ne ee

cessing gutta percha fe wilale foe handing paragutta in these
operations.

Consnanren Proruiiaus or Vaxauersa ano GurTa Perera

Tonite Prageios: Altay sowing insulation Is not subjected
to tensile delecmition in prawticr, Isle peepertes indicate to some
flores the selaive mechanical sualaity ol « given santeril fr #6
Durpoes, Figure § shoves she sere suas characters. of paregutta
fad gotea percha subrisine sable inwlaiion. ‘These results show