Cathodic tiv thaiv: daim ntawv thov thiab cov qauv

Corrosion yog tshuaj lom neeg thiab electrochemical ntawm cov hlau nrog qhov chaw, ua rau nws puas tsuaj. Nws ntws ntawm ntau lub dav, uas yuav txo tau. Los ntawm cov tswv yim ntawm kev pom ntawm kev txaus siab yog qhov anticorrosive cathodic tiv thaiv ntawm hlau qauv nyob rau hauv kev sib cuag nrog rau hauv av, nrog dej thiab nrog thauj media. Tshwj xeeb raug puas yog txheej sab nraud ntawm cov kav dej los ntawm kev ua av thiab cov dej ntws ntws.

Sab hauv, kev txheeb ze yog nyob ntawm cov khoom ntawm qhov nruab nrab. Yog tias nws yog ib qho roj, nws yuav tsum tau ntxuav kom huv si ntawm cov dej noo thiab cov tshuaj phem: hydrogen sulphide, oxygen, etc.

Ntsiab cai ntawm kev ua haujlwm

Cov khoom ntawm cov txheej txheem ntawm cov hluav taws xob hluav taws xob yog cov nruab nrab, cov hlau thiab cov kev cuam tshuam ntawm lawv. Qhov nruab nrab, feem ntau yog ntub dej los yog dej, muaj hluav taws xob ua kom zoo. Ib qho hluav taws xob tau tshwm sim ntawm qhov nruab nrab ntawm nws thiab cov qauv hlau. Yog hais tias qhov tam sim no yog qhov zoo (anode electrode), cov hlau ions kis mus rau hauv qhov kev daws teeb meem, uas ua rau poob ntawm qhov loj ntawm cov hlau. Cov tshuaj tiv thaiv ua rau corrosion. Muaj ib qho tsis zoo tam sim no (cathode electrode), cov kev piam sij no tsis tuaj yeem, vim tias electrons kis mus rau hauv cov tshuaj. Cov qauv no yog siv rau hauv electroplating rau txheej hlau uas tsis yog ferrous hlau.

Cathodic corrosion tiv thaiv yog nqa tawm thaum tsis muaj peev xwm siv rau qhov khoom los ntawm cov hlau.

Rau lub hom phiaj no, ib qho anode electrode yog muab tso rau hauv cov av thiab lub peev xwm zoo yog txuas nrog nws los ntawm lub hwj chim los. Ib qho raug rho tawm yog siv rau qhov khoom tiv thaiv. Cathodic-anodic tiv thaiv ua rau kev puas tsuaj ntawm anode electrode ntawm corrosion xwb. Yog li ntawd, nws yuav tsum tau hloov zuj zus.

Kev tsis zoo ntawm cov hluav taws xob hluav taws xob

Corrosion ntawm cov qauv yuav tshwm sim los ntawm qhov kev txiav txim ntawm stray currents ntog los ntawm lwm lub tshuab. Lawv yog cov tseem ceeb rau cov khoom siv phiaj, tab sis ua rau kev puas tsuaj rau cov qauv nyob ze. Kev khiav dej ntws tuaj yeem kis tau los ntawm cov tsheb ciav hlau thauj mus los. Lawv nkag mus rau hauv cov kev taw qhia ntawm lub substation thiab poob mus rau cov kav dej. Ntawm qhov tawm los ntawm lawv, anodic chaw raug tsim, ua qhov khaus corrosion. Rau kev tiv thaiv, hluav taws xob fais fab - siv tshwj xeeb tapping ntawm currents ntawm lub raj xa mus rau lawv qhov chaw. Nws tseem yog tau cathodic tiv thaiv ntawm pipelines tiv thaiv corrosion. Ua li no, nws yog qhov tsim nyog yuav tsum paub qhov siab tshaj plaws ntawm cov dej ntws, uas yog ntsuas los ntawm cov cuab yeej tshwj xeeb.

Raws li cov txiaj ntsig ntawm kev ntsuam xyuas hluav taws xob, txoj kev tiv thaiv cov roj siv raj yog xaiv. Universal txhais tau tias yog ib tug passive txoj kev ntawm yeeb nkab rwb thaiv tsev los ntawm qhov av hu los ntawm lub insulating coatings. Cathodic tiv thaiv ntawm qhov roj pipeline yog ib txoj kev kom nquag plias.

Pipeline Protection

Cov txheej txheem hauv av yog kev tiv thaiv los ntawm kev txhuam tawm yog tias lawv txuas ib qhov rho tawm DC qhov chaw rau lawv, thiab ntxiv rau - rau anode electrodes faus rau hauv av. Qhov tam sim no yuav mus rau tus tsim, tiv thaiv nws ntawm corrosion. Yog li, cathodic tiv thaiv ntawm pipelines, reservoirs los yog pipelines nyob rau hauv hauv av yog ua.

Qhov anode electrode yuav raug rhuav tshem, thiab nws yuav tsum tau hloov zuj zus. Rau ib lub tank muaj dej, cov electrodes yog muab tso rau sab hauv. Hauv qhov no, cov kua yuav yog ib qho roj ntsha uas siv tam sim no yuav ntws tawm ntawm cov anodes mus rau ntawm lub thawv. Electrodes zoo tswj thiab yooj yim los hloov. Hauv av, qhov no nyuab dua tuaj.

Fais fab mov

Ze rau cov roj thiab cov pa pipes, nyob hauv cov chaw ua haujlwm siv cua kub thiab dej, uas yuav tsum tau siv kev tiv thaiv cathodic, tsim kom muaj cov chaw nres tsheb, los ntawm qhov ntsuas hluav taws xob rau cov chaw. Yog tias lawv muab tso rau hauv cov cua qhib, lawv cov kev tiv thaiv lawv yuav tsum tsis txhob qis dua IP34. Rau cov chav qhuav, ib qho yog tsim.

Qhov chaw cathodic tiv thaiv cov kav dej roj thiab lwm cov txheej txheem loj muaj zog ntawm 1 mus rau 10 kW.

Lawv lub zog feem ntau yog nyob ntawm seb cov nram no:

• Kev tswj ntawm av thiab anode;
• Cov hluav taws xob hluav taws xob;
• Ntev ntawm qhov chaw tiv thaiv;
• Insulating kev txiav txim ntawm lub txheej.

Feeb ntau, lub cathodic tiv thaiv converter yog ib qho kev tsim vaj tse. Tam sim no nws yog hloov los ntawm ib tug inverter, uas muaj me qhov loj me, zoo tam sim no stability thiab ntau dua kev khwv nyiaj txiag. Hauv cov cheeb tsam tseem ceeb, nruab ib lub chaw tswj uas muaj kev tswj hwm tam sim no thiab qhov muaj zog, sib npaug sib npaug, thiab lwm yam.

Cov khoom siv no muaj nyob rau hauv kev ua lag luam hauv ntau yam kev hloov. Rau cov kev xav tau ntawm cov ntaub ntawv kev cai tsim, muab qhov zoo tshaj plaws ua hauj lwm tej yam kev mob.

Tam sim no qhov tsis

Kev tiv thaiv tiv thaiv kom tsis txhob muaj hlau, qhov peev xwm tiv thaiv yog 0.44 V. Hauv kev xyaum, nws yuav tsum yog ntau dua vim hais tias muaj kev cuam tshuam ntawm cov thawv thiab lub xeev ntawm cov hlau npoo. Cov nqi siab tshaj plaws yog 1 V. Nyob rau hauv lub xub ntiag ntawm hlau coatings rau tam sim no ntawm cov electrodes yog 0.05 MA / m ^2. Yog hais tias lub rwb thaiv tsev lawm, nws yuav tsub rau 10 MA / m ^2.

Cathodic tiv thaiv zoo siv nrog lwm txoj kev, vim tsis muaj zog dua. Yog tias muaj xim pleev xim rau ntawm cov qauv ntawm cov qauv, tsuas yog cov chaw uas nws muaj kev ntxhov siab yog cov tiv thaiv electrochemically.

Nta ntawm kev tiv thaiv cathodic

1. Cov hwj chim yog cov noj los yog cov tshuab hluav taws xob.
2. Qhov chaw ntawm lub anode earthing keyboards yog nyob ntawm cov dej ntshiab. Txoj kev npaj yuav muab faib los sis ua kom zoo, thiab yuav tsum nyob rau ntawm qhov sib txawv ntawm qhov sib txawv.
3. Cov khoom siv anode yog xaiv nrog tsawg solubility kom txaus rau 15 xyoo.
4. Lub peev xwm ntawm kev tiv thaiv rau txhua qhov kav dej yog xam. Nws tsis yog tswj hwm yog tias tsis muaj kev tiv thaiv cov txheej txheem.

Gazprom tus qauv tsim rau kev tiv thaiv cathodic

• Kev txiav txim siab thoob plaws hauv lub neej ntawm cov khoom siv tiv thaiv.
• Kev tiv thaiv tawm tsam atmospheric overvoltage.
• Kev tso chaw ntawm lub chaw nres tsheb hauv block-thawv los yog nyob rau hauv tus kheej-kheej kev tsoo khoom.
• Anode grounding yog xaiv nyob rau hauv cov cheeb tsam nrog ib yam tsawg kawg hluav taws xob tsis kam ntawm hauv av.
• Cov yam ntxwv ntawm cov khoom siv sib tw tau xaiv rau kev suav nyiaj rau kev laus ntawm kev tiv thaiv ntawm lub raj xa dej.

Cov tiv thaiv kev tiv thaiv

Cov txheej txheem yog hom cathodic tiv thaiv nrog kev sib txuas ntawm electrodes los ntawm ntau cov hlau electronegative los ntawm qhov chaw nruab nrab ntawm hluav taws xob. Qhov txawv yog thaum tsis muaj zog. Tus neeg tiv thaiv yuav siv qhov sib txhuam ntawm nws tus kheej, dissolving nyob rau hauv qhov chaw ua hluav taws xob hluav taws xob.

Ob peb xyoo tom qab, lub anode yuav tsum tau hloov, vim nws yog tsim.

Cov nyhuv ntawm qhov anode tsub kom nrog ib tug thawj hauv nws lub tsis kam nrog lub nruab nrab. Sij hawm dhau mus, nws muaj peev xwm them rau ib txheej corrosive. Qhov no ua rau muaj kev sib tshuam ntawm qhov hluav taws xob. Yog hais tias qhov anode muab tso rau hauv ib qho dej ntawm cov ntsev, uas dissolves corrosion cov khoom, qhov nce nce.

Tus cawv ntawm tus taw tsuas yog tsawg. Radius txiav txim los ntawm lub fais kuj ntawm lub nruab nrab thiab lub peev xwm sib txawv ntawm anode thiab cathode.

Cov tiv thaiv tiv thaiv yog siv thaum tsis muaj zog los yog thaum lawv siv nyiaj txiag tsis zoo. Nws kuj yog qhov tsis zoo thaum siv nyob rau hauv acid xov xwm vim hais tias ntawm high dissolution rate ntawm lub anodes. Protectors raug ntsia hauv dej, hauv av los yog hauv qhov chaw nruab nrab. Anodes ntawm ntshiab hlau feem ntau tsis ua. Kev tshem tawm ntawm zinc tshwm sim los ntawm unevenly, magnesium corrodes dhau lawm, thiab muaj zog zaj duab xis ntawm oxides cov ntaub ntawv ntawm txhuas.

Cov ntaub ntawv pov thawj

Kom cov neeg tiv thaiv tau qhov tsim nyog ua tau zoo, lawv tau ua los ntawm kev sib tov nrog cov nram qab no.

• Zn + 0.025-0.15% Cd + 0.1-0.5% Al - tiv thaiv cov khoom hauv seawater.
• Al + 8% Zn + 5% Mg + Cd, Hauv, Gl, Hg, Tl, Mn, Si (feem pua sib koom) - kev lag luam ntawm cov khoom hauv kev khiav dej hiav txwv.
• Mg + 5-7% Al + 2-5% Zn - kev tiv thaiv ntawm cov khoom me me hauv av los yog hauv dej nrog cov qaub concentration uas tsis muaj ntsev.

Kev ua txhaum cai ntawm qee hom kev tiv thaiv ua rau tsis zoo. Anodes los ntawm magnesium tuaj yeem ua rau cracking ntawm cov khoom vim qhov kev loj hlob ntawm hydrogen embrittlement.

Tiv thaiv treadmob nrog co anticorrosion coatings nce nws cov lus.

Kev faib tawm ntawm kev tiv thaiv tam sim no pab tau, thiab cov anodes yuav tsum tau tsawg dua. Ib qho magnesium anode tiv thaiv lub kav dej npog ntawm qhov ntev ntawm 8 km, thiab tsis muaj txheej - tsuas yog 30 m.

Kev tiv thaiv ntawm lub cev lub cev los ntawm corrosion

Yog tias muaj kev ua txhaum cai ntawm lub txheej, lub thickness ntawm lub tsheb cev yuav txo tau 5 xyoos mus rau 1 hli, i.e. xeb dhau. Restoration ntawm tiv thaiv txheej txheem yog ib qho tseem ceeb, tab sis apart from nws muaj ib txoj kev rau kom nres txoj kev txhuam hniav nrog kev pab los ntawm cathodic tiv thaiv. Yog tias koj tig lub cev mus rau hauv ib lub cathode, hlau hlau nres nres. Anodes tuaj yeem ua rau txhua yam khoom siv, nyob tom ntej: hlau daim hlau, lub voj voog av, chaw nres tsheb, kev ntub dej. Nyob rau hauv cov ntaub ntawv no, qhov ua tau zoo ntawm kev tiv thaiv nce nrog kev loj hlob ntawm anode cheeb tsam. Yog hais tias qhov anode yog ib txoj kev saum npoo, ib tug "tail" ntawm cov khoom siv roj rub tau siv los hu rau nws. Nws tso rau hauv pem hauv ntej ntawm lub log kom tau ib qho tshuaj zoo dua. "Tail" yog cais tawm ntawm lub cev.

Rau qhov anode, ib qho ntxiv roj teeb txuas nrog ntawm 1 kΩ resistor thiab ib tug LED nyob rau hauv kev txuas nrog nws. Thaum lub Circuit Court raug kaw los ntawm lub anode, thaum lub rho tawm yog txuas rau lub cev, hauv kev lag luam, qhov muag pom tsis tshua zoo. Yog hais tias nws muaj teeb ci, nws txhais tau hais tias lub luv luv Circuit Court tau tshwm sim hauv Circuit Court. Yog vim li cas yuav tsum tau pom thiab tshem tawm.

Txhawm rau tiv thaiv lub circuit nyob rau hauv series, ib tug fuse yuav tsum tau ntsia.

Thaum lub tsheb nyob hauv qhov chaw nres tsheb, nws txuas nrog rau qhov av anode. Thaum lub sij hawm lub zog, qhov kev twb kev txuas yog ntawm tus "Tail".

Xaus

Cathodic tiv thaiv yog ib txoj kev los txhim kho txoj haujlwm kev cia siab ntawm cov kav dej hauv av thiab lwm cov qauv. Nyob rau hauv qhov no, nws yuav tsum ua rau hauv nws cov nyiaj tsis zoo rau cov kav dej uas nyob ib puag ncig ntawm kev cuam tshuam ntawm cov dej tseb tsoo.