r ,.,s ented to th, , (': . ·nal.'A.eaoc1tion ot ' _D. a~ 0 > Fllg1n re on ~ebJ.'"UAh 12, 1954 Br A. R Murdieon EXPIRIEROES IN CORROOION CO NTROL PIPELINE OHA PRODUCTS TM subject of Corroeion., or loss or iron and Jteel and inttrt.t other metal pi-oducts clue to electro-~hemical aotion is or vital to eve?"70fte. Thi• lose on a continent - wide baa1a runs into billion• an'1 technical aepeot, ot corroeim o! dollars annually-. Th• theoretical a.rd ita cont.rel have been covered 1n IWl1' exoell,nt. paper.. 'Ibis af\emoon I wieh to deal. 1n an informal manner with ecme experiences and. practical. aspects ot corn>sioti control., on one particular plant eubject to its evil1 • namel.7, the refined producte The Sarnia Products Pipe Line consists ci 12 and 10 inch pipe am about 12 miles ot type ot pipe line. of about 188 milee 6 inch spur line. Since a jor part or n very l&r ge inv eotment wn11to be put in the ground., cathodic protection ot t.he line was included in t..he design ReTiewing veey briof'l;y corrosion protection by •ane .from the outset. ot cathodic protection, n recall the corro ion or ruat.ing of eteel or iron ie an elect:ro-chemical In thie electric dil"ect Thie current to th e cathode. and enter • the electrolyte c&aea. In th e cathodic s.. torc ed into b thus u. t rancsf erring that convention corrosion occurs, technique protection th e corrosion f'lowe 1"romthe anode thro It ie vb -ere the current ing th e cathom b)" \nto being the anode. process. thOlJ8ht ot ae the ao called ie w,~ cun-ent. and bT the standard the el. ctrolyte that a chmca.1 action accompanied by the tlov or an proceee we ha" current. ot for a moment., the principle• Ill! leavee the anode except in a few special the structure ani, or externall::r to be protect ed appli ed pot enti al a, to eome expendab1 e etru .ctur e 1,tiJ.cb i • ! ore All cathodic prot ecti on sys t ems wor k oo t.Jii o prtncipl.e . -2!be IIIDUDtof current required to toroe tb• pipe or other structure into beha.11.nc •• a cathode 11 a function of UD7 vari.abl••• ho •t th• IIOe\ iaport,ant are t.h• re11i1tirlt7 or reeiltence per unit YOlwuof the IOU, and the d.1gree ot lneul.ation between the structUN Bt aona1derine otuu law, inaulation nquiNd \he nbject the lea, current that will &la•• ch••clot.b-lik• •t or abcNt ,;,2• tor tenail• am clllring am. atter 1a being la1d. 1a checked tor 1nwlat1on Thia little into vbich 11 wrapped a lib,.. instrument applies 10 0, but. the hi gh voltage opmoaticn. pulses in the coating. e.cros• ground U... t.tw pl"eNllt. ~on. vith Und.er oert.ain The wltage 1• u tld• a ftr'T port.ion of the pipe O\lt. into tJw coat.inc. area ot pipe \he bole in anod.e ed actU&l. l.ou \o rapi.d of ...t.al make a a1.&e b1 the corroaion will l.uk ..all w1ll be -11, 1n web and applied there i• i• DOt ~ but a pipe pl.ace it line. RNl pipe u can be Md• with arJ7 turtber at bol• 1l\ the ooatiq. ...ii Ual. such a• to oanae cur1W1t• t.o tiov thh perfect en. llicbt. lllODder vh7 w need bother oonditione or JHp. ooat..ing. a coat.ing vbiab Cond.der tor a .,..nt coat.inc the coat~ W• naw h&'ft about. 200 ldl.ee ot very valuable 1n th• The d.teotor 1• mna.ll e o ug.'1 eo that pu.l.N width while the pl,e against d-.• ot a •Holidq" Manti t.o burn or damage th• tlllera A lay-er ot felt, paper 1• at.nngth. the b&cktUling by l.Mk• vill. det.eot. eTen tJ.D7 pinhole• Wl'iecl u to ot ooal tar, Thi• ooatSnc Ocmaieta ot a lq9r a.ppl.iad crnr the coatin&, u protection mough be of pipe ooat1n&. OUr Sarn1a Product• pipe line 1• wrapJ*l and eaewl a.pplied hot to a depth abcNt, Thi• brinp an adequat• pipe to 90il potential. ooatecl throughout its length. \he it cant>. aeen that the better th• bet.wen t.he pipe and t.he eoil, to attain the soil. and 11&.Ybe M1bject to a pote- the • under the bol.e will at th!.• t.akH 110il eleot.rol.yt,e onl7 one point. a TU'T ...U. 'ftle bole M .,. for th• abne ill t.h• long rm la a pipe we belitft rtUOll9, wt~••aoo4a ooa\lq •1-'l• that the belt a, poaaibl.e, toll.on4 bJ a qlMll&tio appl.ioa\loa ot oathodi.o ,rot•oUcD· Wit.ha aooct ooa\.tq, one aovo• oan protect; &bolt\ 30 t.• 40 1111•• ot pipe• O\ll"Nllt •N Ill Ont.u-1• eleot.n.t powr 1a nad.UJ aY&ll&bl•, tlat obriou• ohoic• ot a current .. urce la & a•]l t,vo probln8 HaflDIdeoiclN. C'a Nleni\111 rectititr. r, e1n.. - the aiH ot th• GVNnt •ouroe and d18t.ribuU.011along th• pipe 11.M, "1th perh&Pf the \bird \n,e of structure to UH as • apode at. MChl"•o\itier ear~ •ta&•• to MIIPl• the p1.&nn1.q el.on& the line. At. thi.• corro•1on control• • ot teneea, n\ a•peote ot boot•, irate •priJI&•, etc. t&r1111r•and their One ot our lllllbeN ot this pr•ll.minarJ"work and will OUT'J' out nch tb•• a:14tl1pt•, bear I am .... en ot •uuremnta, clll"ft• of p1.,. oo..un& pertol"ll&nceunder n.riou and anaed with, .. w at Yariou point• soil reaiatirlt7 obtained a tairly- cOllplete llow h&Yin& conditiou, .S.\•. w enter 11PQDth• pre.ctioal broken aut.omobU. helped wt on .,. point, barbed. ~ legendarT daughten, here prennt problea ot tbe Aocordin&l-7,a prel1m1Mr7 1NrV•7wu oarri84 Ou\ 1n eoil re11.8ti'fi.t7. th• the nlJlllb•r -4 l• • tunotion ot the ooaUnc and the ratin& ot th• reotit1er, th• CllU'ND~ .. llJ'M, UIOIIDt ot ourrent, anct \hen- As we pointed out, before ti. ton, the wre ourrent ~t.8 able to Mk• a reUCJIIAbl.T&00\Q'&te 1111clOUl"Nllt. 1ouro• 8J>&Cin&•uter caloul&\1.on ot appl.JS.naa a••rou aatet7 factor tor ooaUnc deter1oratlon and th• prob&bllit.7 t.ba\ panllel •truotun• •pen, wuld efta\\l&l.17 be bended to our pipe, w 1tan4ardiled 2, TOlt Nl.1111• rectitien, naak input TOltage and theNtore •uoh unit• vu •till ground. wi\h a tap ld.jQtlimt. ournnt Olltpat. ca 10 f'or reot1tutt The required mmber ot 1CIMWhat. Mbulou1, since t.hl pipe wu not yw\ 1D ~ - 4 ... Xnofd.•~ \o ff.4111\ate anal,-i1 proteott.,ca eq,uli-a,, • dtoicltcl \o lnltall u.. . al.one tb• ••Jl,...\herproot 11Pto a ten 4\ o.JVJ.n point, \w ot • pertol'llll4. .... uncl, 'f&].uable Ncs\itl•n. apUecl bepn la& a ~ "°look NOUOD l•i.on nm Re ot tbl direnia11 IDd.eapi t.urie ot the WR 1-a41, . anotur pl.ot,ted ot t.b• al.GIii the liu Oll'l'ff *" troa 1nd1oaied tut at. apJ)l'Oldlla~ u U w would reqaire ~· lllfft1' wre re911lt.a. Thi• ...U reotit1en ,0 mile 1Atenal.1. Id.a reot1t1er be I\ \Jiu a1te•, eaoh unit. oner. ot UM 15 Jdl.e• each aide ot the a1teTb8 oheioe ot th• not.Ui•r (we t.llcN&bt). 81x point• eacb poln\ ooan••· aid :ln deciding the n11111Niand loc&\'°8 ot th• Inepeotioa al.OD&ti. VS.thtJi• point• ot Tbl• tiae p1JJI tt aoil po\ent,1&11 at nriou and. ua at'*1aiion eune vu a ao•••• tbe pipe. PollMdn1 \be iu\al ,,.. t. INWIN t.o tend.n&l box tor..., ine\alled, 1Aa41..... 1501 a,-.n t.o pend.\ •alm'wn\ ovrtra\1 t••t lfad• at cm11111•tnterftl• 'ftl•H lea41 OOlllilt ,Of 18 t.ne '1'W lf.fn, ,. •• tht pipe aD4 b""P\ \l.Clll &bou\ IDd test ot ov cathodi&t line. w. wen tint A t1,el4 tri.p in•J)Mt,94 WU •it.ea vu tu t1.na1 pro~ mukecl • t.h4m llllde ml tad•••tor tbe up at. equl ~ 1eaeral UN internla U'Olllld (1) AyatJabUU,7 ot ~ (2) Ooocl road 800 ... (3) Soil ~iTit.7 (4) ~ propert.7 rigb~l-1fllT Tm &ot.ual N90lution d1tt1cult. than orae lligbt aS.oroad• movat.h&t .... _. •• tb• point• 10 llilN .n.m iuciM• ADiJ'GM tuUSar t.bl7 are not, laicl out in a ftl"J' lo1ioal JIOl'e wi\h cntui.0•1 anner. In en tJae up hacl to lM IIONCl ean or WM\ u auob u ill oJICl.- to 1-' an1) a'bl.e powr. at. ot the aboft taot.ora proyecl a 111.t•tha\ h..t a reuonabl.7 1ood rou. md •J• Ia NII ... tht ideal looatlund.eclto b&n1c1ot oopper ll'OQDdJ'Oda. V. to~ a eati1tan017 IOl.ut.ioa to th11 probl• that 1011e ot our pl.ant AHif/ah April 6/54. 11 alreldy ' &N wrkinc •ino• w know traa 1ntpeot.1oa being aubjected to MNP• cort0slon.