DK147164B - INSTALLATION FOR CATHODIC CORROSION PROTECTION WITH FOREIGN FLOW ANNEX - Google Patents
INSTALLATION FOR CATHODIC CORROSION PROTECTION WITH FOREIGN FLOW ANNEX Download PDFInfo
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- DK147164B DK147164B DK044977AA DK44977A DK147164B DK 147164 B DK147164 B DK 147164B DK 044977A A DK044977A A DK 044977AA DK 44977 A DK44977 A DK 44977A DK 147164 B DK147164 B DK 147164B
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- foreign
- reference electrode
- anode
- container wall
- corrosion protection
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- 230000007797 corrosion Effects 0.000 title claims description 35
- 238000005260 corrosion Methods 0.000 title claims description 35
- 238000009434 installation Methods 0.000 title claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 238000009413 insulation Methods 0.000 claims description 7
- 230000001590 oxidative effect Effects 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 description 10
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 7
- 229910052749 magnesium Inorganic materials 0.000 description 7
- 239000011777 magnesium Substances 0.000 description 7
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 230000004913 activation Effects 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 239000012212 insulator Substances 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- 229910021607 Silver chloride Inorganic materials 0.000 description 3
- 239000010405 anode material Substances 0.000 description 3
- 238000002955 isolation Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 3
- GQPLMRYTRLFLPF-UHFFFAOYSA-N Nitrous Oxide Chemical compound [O-][N+]#N GQPLMRYTRLFLPF-UHFFFAOYSA-N 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005485 electric heating Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 239000010936 titanium Substances 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 206010016275 Fear Diseases 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 239000001272 nitrous oxide Substances 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/40—Arrangements for preventing corrosion
- F24H9/45—Arrangements for preventing corrosion for preventing galvanic corrosion, e.g. cathodic or electrolytic means
- F24H9/455—Arrangements for preventing corrosion for preventing galvanic corrosion, e.g. cathodic or electrolytic means for water heaters
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F13/00—Inhibiting corrosion of metals by anodic or cathodic protection
- C23F13/02—Inhibiting corrosion of metals by anodic or cathodic protection cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/40—Arrangements for preventing corrosion
- F24H9/45—Arrangements for preventing corrosion for preventing galvanic corrosion, e.g. cathodic or electrolytic means
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Prevention Of Electric Corrosion (AREA)
Description
1.First
i 147.164 5 Opfindelsen angår et anlæg til katodisk korrosionsbeskyttelse med fremmedstrømanode og· af den i krav l's indledning angivne art.The invention relates to a cathodic corrosion protection plant with a foreign current anode and of the kind specified in the preamble of claim 1.
Varmvandsbeholdere med forholdsvis lille indhold, 10 d.v.s. navnlig til husholdninger, har man hidtil i praksis kun forsynet med et passivt korrosionslag, for det meste af emalje, samt med en offeranode af magnesium. Por det meste har man skruet magnesiumanoden ovenfra ned i beholderen gennem en studs, 15 medens en elektrisk opvarmning kan være anbragt på en flange i den nederste del. I praksis har det vist sig, at sådanne varmvandsbeholdere bliver ødelagt af korrosion allerede efter få år i det nederste område, der optager varmeelemantet.Hot water containers with relatively small contents, 10 i.e. especially for households, so far in practice only a passive corrosion layer, mostly enamel, and a sacrificial anode of magnesium have been provided. For the most part, the magnesium anode has been screwed from above into the container through a stud, while an electric heating may be applied to a flange in the lower part. In practice, it has been found that such hot water tanks are destroyed by corrosion even after a few years in the lower area occupying the heating element.
2020
Udførlige undersøgelser ved hjælp af potential- og strømmålinger har vist, at den nederste trediedel af sådanne vandbeholdere ikke mere er katodisk beskyttet, når opvarmningsflangen ikke er isoleret mod 25 selve varmelegemet, hvad der af elektrotekniske grunde for det meste ikke er tilfældet. Anvendelsen af magnesium-offeranoder har yderligere ulemper, nemlig for det første den, at en magnesiumanode har en betydelig egenkorrosion, hvorved den ofte er fuldstændig 30 ødelagt eller opbrugt efter få år. Endvidere udvikler der sig ved en magnesiumanode en ikke uvæsentlig mængde hydrogengas, der med oxygen kan føre til en knaldgasblanding og dermed være farlig.Extensive studies using potential and current measurements have shown that the lower third of such water containers are no longer cathodically protected when the heating flange is not insulated against the heater itself, which for the most part is not electrotechnical. The use of magnesium sacrificial anodes has further disadvantages, namely, the fact that a magnesium anode has significant intrinsic corrosion, whereby it is often completely destroyed or exhausted after a few years. Furthermore, at a magnesium anode, a not insignificant amount of hydrogen gas develops, which with oxygen can lead to a nitrous oxide mixture and thus be dangerous.
2 147164 1 Til større varmtvandsbeholdere har man allerede foreslået at anvende, fremmedstrøm påvirkede elektroder i stedet for magnesiumofferanoder, se f.eks. "Handbuch des kathodischen Korrosionsschutzes" af Baeckmann -5 Sehwenk, Verlag Chemie GmbH, 1971» kapitel XVI, sider 330 og 331; dette har dog ikke ført til noget tilfredsstillende resultat, fordi de hidtil anvendte fremmedstrømpåvirkede elektroder altid har været indstillet på en bestemt strøm, så at det rigtige poten-10 fcial, når betingelserne i beholderen ændrer sig, f.eks. ved optræden af et yderligere beskadigelsessted i det passive korrosionsbeskyttelseslag, ikke mere er til stede ved beholdervæggen. Desuden giver de hidtidige fremmedstrømpåvirkede elektroder ikke 15 nogen løsning af problemet med den særlige korrosionsfare i nærheden af opvarmningselementet af en varmvandsbeholder med et sådant element. Skaderne i dette område føres tilbage til, at fladerne på opvarmningselementet virker som et katodisk område, 20 ved hvilket oxygen bliver reduceret og dermed kan blive virksom som et oxydationsmiddel, så fejlsteder i det passive korrosionsbeskyttelseslag, der eventuelt findes i det nævnte område, er særlig truet af korrosion.For larger hot water tanks, it has already been proposed to use foreign current-influenced electrodes instead of magnesium sacrificial anodes, see e.g. "Handbuch des cathodischen Corrosionschutzes" by Baeckmann -5 Sehwenk, Verlag Chemie GmbH, 1971 »Chapter XVI, pages 330 and 331; this has not, however, led to a satisfactory result, since the previously used foreign current-influenced electrodes have always been tuned to a certain current, so that the correct potential when the conditions in the container change, e.g. upon occurrence of an additional site of damage in the passive corrosion protection layer, is no longer present at the vessel wall. In addition, the prior foreign current-influenced electrodes provide no solution to the problem of the particular corrosion hazard in the vicinity of the heating element of a hot water tank with such element. The damage in this area is attributed to the surfaces of the heating element acting as a cathodic region, whereby oxygen is reduced and thus becomes effective as an oxidizing agent, so that defects in the passive corrosion protection layer possibly present in said region are particularly threatened by corrosion.
2525
Det er endvidere kendt ved store objekter, f.eks. rørledningssystemer og skibe (nHandbuch des kathodischen Korrosionssehutzes", kapitel VI, sider 151-153)» indenfor rammen af fremmedstrømbeskyttelsesanlæg ved 30 katodisk korrosionsbeskyttelse at anvende spændings regulerende jævnstrømskilder på en sådan måde, at beskyttelsesstrømmen, når forholdene ændrer sig, f.eks. ved optræden af et beskadigelsessted i det passive korrosionsbeskyttelseslag på et skibsskrog, 3 147164 1 automatisk bliver tilpasset til den normale situation.It is also known for large objects, e.g. use piping systems and ships (nHandbuch des cathodischen Korrosionssehutzes ", Chapter VI, pages 151-153)" within the framework of foreign current protection systems by cathodic corrosion protection, to use voltage regulating direct current sources in such a way that the protective current changes when conditions change, for example. the occurrence of a site of damage in the passive corrosion protection layer of a ship's hull is automatically adapted to the normal situation.
Den foreliggende opfindelse har til formål at anvise 5 et anlæg til katodisk korrosionsbeskyttelse, hvilket anlæg fortrinsvis er bestemt til forholdsvis små varmvandsbeholdere med opvarmningselement, f.eks. husholdningsbeholdere, men også kan anvendes til andre beholdere og til andre formål, f.eks. til be-10 holdere uden elektrisk opvarmning eller andre flader, der skal beskyttes, og som kan monteres enkelt og med lille indsats af personale, også af uøvede personer.The present invention has for its object to provide a cathodic corrosion protection system which is preferably intended for relatively small hot water tanks with heating elements, e.g. household containers, but can also be used for other containers and for other purposes, e.g. for containers without electric heating or other surfaces to be protected, which can be mounted easily and with little effort by personnel, including by unskilled persons.
15 Dette opnås ifølge opfindelsen ved, at anlægget til korrosionsbeskyttelse er udformet som angivet i krav l's kendetegnende del.This is achieved according to the invention in that the corrosion protection system is designed as defined in the characterizing part of claim 1.
Ved denne udformning opnår man, at også forholdsvis 20 små varmvandsbeholdere med en forholdsvis lille ind-· sats kan reguleres og beskyttes nøjagtigt spændingsreguleret, så beskyttelsesstrømmen, så snart der under driften af beholderen opstår et beskadiget sted i det passive korrosionsbeskyttelseslag, automatisk 25 bliver forøget og tilpasset til den nye situation.By this design, it is achieved that also relatively small 20 hot water tanks with a relatively small insert can be precisely regulated and protected voltage, so that as soon as during the operation of the container a damaged place in the passive corrosion protection layer, the protective current is automatically increased 25 and adapted to the new situation.
Først og fremmest har det herved vist sig, at virkningen af opvarmningselementet som katodisk område når fremmedstrømanoden anbringes umiddelbart ved op-30 varmningselementet, i meget vidt omfang bliver neutraliseret, så at oxygenudskillelsen i dette område bliver kompenseret, og der følgelig ikke mere findes nogen korrosionstrussel på sådanne fejlsteder i det passive korrosionsbeskyttelseslag, der optræder i 4 147164 1 det nævnte område, selv om man oprindeligt netop ved lukkede beholdere, der er udstyret med opvarmningselementer, nærede den frygt, der ikke findes ved fritliggende flader, såsom skibsskrog og rørled-5 ninger, at der på grund af udviklingen af hydrogen navnlig ved opvarmningselementet og udviklingen af oxygen ved en fremmedstrøm påvirket anode ville fås en forøget knaldgasfare.First of all, it has been found here that the effect of the heating element as a cathodic area when the foreign current anode is applied immediately at the heating element is greatly neutralized, so that the oxygen separation in this area is compensated and consequently no corrosion threat exists. at such fault locations in the passive corrosion protection layer occurring in said area, although initially, just at closed containers equipped with heating elements, the fears not found on exposed surfaces such as ship hulls and pipelines 5 It is believed that due to the evolution of hydrogen, in particular by the heating element and the evolution of oxygen by a foreign flow, anode influenced by the gas would be increased.
10 Ved den ifølge opfindelsen stedfindende indstilling af et optimalt potential er hydrogenudviklingen i beholderen i virkeligheden endnu mindre end i en beholder, der er beskyttet ved hjælp af en magne-sium-offeranode, så der i stedet for den uønskede 15 forøgelse af knaldgasfaren ved anvendelse af en frem-medstrømanode i virkeligheden ved anlægget ifølge opfindelsen opnås en væsentlig reduktion af denne fare. Endvidere har anlægget ifølge opfindelsen en meget enkel udformning, og det er kun nødvendigt i 20 den væg, der optager anlægget at udforme en optageåbning. Først og fremmest er montagen af anlægget på grund af udformningen ifølge opfindelsen så enkel, at montagen også kan udføres på kort tid af mindre kvalificerede arbejdskræfter.In fact, in the setting of an optimal potential according to the invention, the hydrogen evolution in the container is in fact even smaller than in a container protected by a magnesium sacrificial anode, so that instead of the undesirable increase in the danger of gas when used of a feed current in fact at the plant according to the invention, a substantial reduction of this hazard is achieved. Furthermore, the system according to the invention has a very simple design, and it is only necessary in the wall that occupies the system to form a recording opening. First of all, the installation of the system due to the design according to the invention is so simple that the installation can also be carried out in a short time by less qualified work forces.
2525
Isoleringen mellem fremmedstrømanode og referenceelektrode kan udformes som angivet i krav 2. Derved sikrer man, at potentialet fra referenceelektrodén ved beholdervæggen måles uforstyrret af påvirkninger, 50 der udgår fra fremmedstrømanoden, idet referenceelektroden befinder sig uden for den såkaldte potentialtragt fra fremmedstrømanoden.The isolation between foreign current anode and reference electrode can be designed as claimed in claim 2. This ensures that the potential of the reference electrode at the container wall is measured undisturbed by impacts 50 starting from the foreign current anode, the reference electrode being outside the so-called potential funnel of the foreign current anode.
Hensigtsmæssigt kan anlægget til korrosionsbeskyt- 5 147164 1 telse også være udformet som angivet i krav 3 og eventuelt i krav b. Perved bliver levetiden af refe-renceelektroden, der for det meste består af Ag/AgCl, væsentlig forlænget.Conveniently, the corrosion protection system may also be designed as claimed in claim 3 and optionally in claim b. As a result, the lifetime of the reference electrode, which is mostly Ag / AgCl, is substantially extended.
55
Det er endvidere fordelagtigt at udforme anlægget til korrosionsbeskyttelse som angivet i krav 5· Derved bliver funktionen af referenceelektroden·, idet en væskestrømning om den forhindres, fordelagtigt på-10 virket på grund af ringspaltens nærhed ved beholdervæggen.Furthermore, it is advantageous to design the corrosion protection system as set forth in claim 5 · Thereby, the function of the reference electrode ·, in that a liquid flow thereof is prevented, is adversely affected due to the proximity of the annular gap to the container wall.
Ved udformningen af anlægget til korrosionsbeskyttelse som angivet i krav 6 opnår man en yderligere 15 forenkling af montagen.In designing the corrosion protection system as specified in claim 6, an additional 15 simplification of the installation is achieved.
Til samme formål kan anlægget til korrosionsbeskyttelse også være udformet som angivet i krav 7- 20 Hensigtsmæssigt kan anlægget til korrosionsbeskyt telse også være udformet som angivet i krav 8, idet det i mange tilfælde er hensigtsmæssigt at anbringe en yderligere fremmedstrømanode i et andet område af beholderen, f.eks. når man. vil anbringe en fremmed-25 strømanode i nærheden af en opvarmning i den nederste del af beholderen og en yderligere fremmedstrømanode i det øverste område af en i det væsentlige cylindrisk udformet beholder.For the same purpose, the corrosion protection system may also be configured as claimed in claims 7- 20 Conveniently, the corrosion protection system may also be configured as claimed in claim 8, in many cases it being appropriate to place an additional foreign flow anode in another region of the container. , eg. when you. will place a foreign flow anode in the vicinity of a heating in the lower portion of the container and a further foreign flow anode in the upper region of a substantially cylindrical container.
30 Da en plastikdel·, der omfatter holder og isolerings--stykke, ifølge den beskrevne udførelsesform er forholdsvis dyr i fremstilling, og da yderligere anbringelsen af referenceelektroden i en ringformet udsparing i isoleringsstykke er noget vanskelig, kan 6 147164 1 anlægget til korrosionsbeskyttelse også hensigtsmæssigt være udformet som angivet i krav 9· Ved denne udformning bliver konstruktionen yderligere forenklet , og dette gælder såvel med hensyn til de fornød-5 ne enkeltdele som også med hensyn til sammensætningen , af dem.Since a plastic member comprising bracket and insulation piece according to the embodiment described is relatively expensive to manufacture, and since further placing the reference electrode in an annular recess in insulation piece is somewhat difficult, the corrosion protection system may also be conveniently The design is further simplified, and this applies both to the individual parts as well as to the composition thereof.
Det har vist sig, at det oxydationslag, der dannes på fremmedstrømanodematerialet, ved anvendelse af 10 et egnet materiale er tilstrækkelig til den nødvendige isolering mellem fremmedstrømanoden og referenceelektroden, så at holderen til fremmedstrøma-node og referenceelektrode kan udføres væsentlig enklere, navnlig kortere, og dermed mere økonomisk.It has been found that the oxidation layer formed on the foreign current anode material using a suitable material is sufficient for the necessary isolation between the foreign current anode and the reference electrode, so that the holder for the foreign current node and reference electrode can be made substantially simpler, especially shorter, and thus more economical.
1515
Det har herved vist sig særlig fordelagtigt af udforme anlægget til korrosionsbeskyttelse som angivet i krav 10. Naturligvis kan også andre egnede anodematerialer anvendes på lignende måde med et 20 egnet aktiveringsovertræk i det område, der ikke' skal være isoleret overfor referenceelektroden.It has thereby proved particularly advantageous to design the corrosion protection system as set forth in claim 10. Of course, other suitable anode materials can also be used in a similar manner with a suitable activation coating in the area which is not to be isolated from the reference electrode.
Når det isoleringsstykke, der omgiver fremmedstrømanoden ved den ovenfor nævnte udførelse, falder 25 bort, kan anlægget til korrosionsbeskyttelse hensigtsmæssigt også være udformet som angivet i krav 11.Conveniently, when the insulator surrounding the foreign-current method of the above-mentioned embodiment fails 25, the corrosion protection system may be designed as claimed in claim 11.
Hensigtsmæssigt kan anlægget til korrosionsbeskyttelse også være udformet som angivet i krav 12. Her-30 ved opnår man, at hulrummene i det porøse legeme selv vil virke som strømningsforhindrende middel. Særlig egnet hertil har f.eks. en refereneeelektrode af sølvklorid vist sig.Conveniently, the corrosion protection system may also be designed as claimed in claim 12. Hereby it is obtained that the cavities in the porous body itself will act as a flow preventing agent. Particularly suitable for this, e.g. a silver chloride reference electrode is shown.
7 147164 1 Endelig er det også fordelagtigt at udforme anlægget til korrosionsbeskyttelse som angivet i krav 13. Ved denne udformning kan man opnå, at holderen kan fremstilles af et fast metallisk materiale, hvad der er 5 af særlig betydning for holderens aftætning ved indsætning, navnlig ved indskruning i en metallisk beholder.Finally, it is also advantageous to design the corrosion protection system as set forth in claim 13. In this embodiment, it is possible to achieve that the holder can be made of a solid metallic material which is of particular importance for the sealing on insert, in particular by screwing into a metallic container.
Anlægget til korrosionsbeskyttelse forklares nærmere 10 under henvisning til tegningen, på hvilken fig. 1 skematisk viser en udførelsesform for anlægget indbygget i en beholdervæg og i lodret snit, 15 fig. 2 et lodret snit gennem en anden udførelses-form for anlægget i fig. 1, fig. 3 en tredie udførelsesform for anlægget, og 20 fig. 4 en fjerde udførelsesform for anlægget svarende til den i fig. 3 viste konstruktion.The corrosion protection system is explained in more detail with reference to the drawing, in which: FIG. 1 is a schematic representation of an embodiment of the system built into a container wall and in vertical section; FIG. 2 is a vertical section through another embodiment of the system of FIG. 1, FIG. 3 shows a third embodiment of the plant, and FIG. 4 shows a fourth embodiment of the system similar to that of FIG. 3.
25 I en beholdervæg 1 findes en gevindstuds 2, i hvilken en holder 3 med en tilsvarende gevinddel 4 er indskruet. Holderen 3S der fortrinsvis består af plastik, er fortsat ind i det indre af beholderen med et isoleringsstykke 53 i hvilket der i nærheden af behol-30 dervæggen 1 findes en ringformet udsparing 6, i hvilken en vindelformet referenceelektrode 7 af Ag/AgCl er anbragt. Udsparingen er dækket af' et cylindrisk hylster 8 af væskegennemtrængeligt materiale, f.eks. et porøst keramikhylster eller en gennem- 8 147164 1 hullet kappe.In a container wall 1 there is a threaded nozzle 2 in which a holder 3 with a corresponding threaded part 4 is screwed in. The holder 3S, which is preferably made of plastic, is continued into the interior of the container with an insulating piece 53 in which is located near the container wall 1 an annular recess 6, in which a winding shaped electrode 7 of Ag / AgCl is arranged. The recess is covered by a cylindrical casing 8 of liquid-permeable material, e.g. a porous ceramic sheath or a pierced sheath.
Centralt gennem hele holderen 3 og isoleringsstykket 5 strækker sig en fremmedstrømanode 9* og læng-5 den af isoleringsstykket 5 er det flerdobbelte af afstanden af den frie ende af refereneeelektroden 7 fra beholdervæggen 1.Centrally throughout the holder 3 and the insulator 5 extends a foreign current anode 9 * and the length of the insulator 5 is multiplied by the distance of the free end of the reference electrode 7 from the container wall 1.
På et hoved 10 på holderen 3 er der fastgjort en 10 spændingsregulator 11. Endvidere findes der i hove det 10 en elektrisk forbindelse 12 mellem spændingsregulatoren 11 og referenceelektroden 7 samt yderligere elektrisk forbindelse 13 mellem spændingsregulatoren 11 og fremmedstrømanoden 9. Endelig findes 15 der en yderligere elektrisk forbindelse lk mellem spændingsregulatoren 11 og beholdervæggen 1 eller gevindstudsen 2 ved hjælp af en kærvskrue 15, der er indskruet i gevinddelen 5 i holderen 3· 20 På spændingsregulatoren 11 findes en tilslutning 16 til strømforsynings f.eks. med 220V vekselstrøm, samt en yderligere tilslutning 17 til forbindelse med andre fremmedstrømanoder, der skal anbringes på andre steder i beholderen.On a head 10 of the holder 3 is attached a 10 voltage regulator 11. Furthermore, in the main there is an electrical connection 12 between the voltage regulator 11 and the reference electrode 7 and further electrical connection 13 between the voltage regulator 11 and the foreign current method 9. Finally, there is an additional electrical connection lk between the voltage regulator 11 and the container wall 1 or the threaded nozzle 2 by means of a notch screw 15 screwed into the threaded part 5 of the holder 3 · 20 On the voltage regulator 11 there is a connection 16 for power supply e.g. with 220V alternating current, as well as an additional connection 17 for connection to other foreign current anodes to be placed elsewhere in the container.
2525
Ved udførelsesformen i fig. 2 findes et cylindrisk hylster 8a for den vindelformede referenceelektrode 7, hvilket hylster har en lukket kappeflade. Mellem beholdervæggen 1 og hylstrets begyndelse er der en 30 spalte 18 til en udsparing 6 på en sådan måde, at den væske, der omgiver referenceelektroden 7, er hindret i strømning, medens funktionen af referenceelektroden 7 er optimal, fordi spalten 18 er nær ved beholdervæggen 1.In the embodiment of FIG. 2, a cylindrical casing 8a for the winding reference electrode 7 is provided, which casing has a closed casing surface. Between the container wall 1 and the beginning of the casing, there is a slot 18 for a recess 6 in such a way that the liquid surrounding the reference electrode 7 is hindered in flow, while the function of the reference electrode 7 is optimal because the slot 18 is close to the container wall. first
9 147164 1 Med. en spændingsregulator forstås et reguleringsapparat, der har den opgave at holde en måleelektrode i en elektrokemisk celle på et konstant potential, der er indstilleligt med en skal-spændingsgiver, i 5 forhold til en referenceelektrode. Til dette formål forstærker spændingsregulatoren en meget lille afvigelse i potentialet fra måleelektroden fra skalspændingen og regulerer dermed den strøm, der går gennem cellen mellem måleelektroden og modelektroden.9 147164 1 Med. a voltage regulator is understood to be a control apparatus having the task of holding a measuring electrode in an electrochemical cell at a constant potential adjustable by a shell voltage transducer relative to a reference electrode. For this purpose, the voltage regulator amplifies a very small deviation in the potential of the measuring electrode from the shell voltage and thus regulates the current passing through the cell between the measuring electrode and the model electrode.
1010
Dette funktionsprincip overføres til det foreliggende tilfælde af katodisk korrosionsbeskyttelse med fremmedstrøm ved hjælp af spændingsregulatoren 11 og referenceelektroden 7 til den genstand, der 15 skal beskyttes og danner måleelektroden, nemlig beholdervæggen 1, der påtvinges et sådant negativt potential, at en korrosion forhindres, og der optræder den mindst mulige hydrogenudvikling. Afviger potentialet på beholdervæggen 1 fra den givne skal-20 spænding, forstærker spændingsregulatoren denne lille afvigelse og regulerer dermed den ved anlægget til korrosionsbeskyttelse mellem beholdervæggen 1 og fremmedstrømanoden 9 gående strøm således, at potentialet beholder sin konstante værdi. På grund 'af 25 det derved fast bestemte potential sikres en konstant og vedvarende korrosionsbeskyttelse. Den uønskede hydrogenudvikling bliver i vidt omfang forhindret og på grund af den spændingestyrede indkobling af strømmen netop indreguleret på den størrelse, der 30 er påkrævet til korrosionsbeskyttelse, så at et unødigt strømforbrug undgås.This principle of operation is transferred to the present case of cathodic corrosion protection with foreign current by means of the voltage regulator 11 and the reference electrode 7 to the object to be protected and forms the measuring electrode, namely the container wall 1, which is forced to such a negative potential that a corrosion is prevented and occurs the least possible hydrogen evolution. If the potential of the container wall 1 deviates from the given shell voltage, the voltage regulator amplifies this small deviation and thus regulates the current flowing through the plant for corrosion protection between the container wall 1 and the foreign current method 9 so that the potential retains its constant value. Due to the thus determined potential, constant and sustained corrosion protection is ensured. The undesirable hydrogen evolution is largely prevented and, due to the voltage controlled switching on of the current, precisely adjusted to the size required for corrosion protection so that unnecessary power consumption is avoided.
En spændingsregulator, der er nødvendig til en hus-holdnings-varm-vandsbeholder med ca. 80 Ί rumindhold, 147164 ίο 1 - består i det væsentlige af en transformer 220/2x18V, en ensretter- og stabiliseringsdel, bestående af ensrettere, zener-dioder, transistorer, kondensatorer, modstande, en såkaldt skal-spændingsgiver, bestående 5 af dioder, modstande og potentiometre, en differens-og forforstærker opbygget som integreret kredsløb og to transistorer som 'effektforstærkende udgangstrin. Enkelthederne ved en sådan spændingsregulator danner ikke nogen del af den foreliggende opfindelse 10 og skal derfor heller ikke beskrives nærmere.A voltage regulator needed for a domestic hot water tank of approx. 80 Ί space content, 147164 ίο 1 - consists essentially of a transformer 220 / 2x18V, a rectifier and stabilizer portion consisting of rectifiers, zener diodes, transistors, capacitors, resistors, a so-called shell voltage generator, consisting of 5 diodes, resistors and potentiometers, a differential and preamplifier built as an integrated circuit and two transistors as' power amplifier output stages. The details of such a voltage regulator do not form any part of the present invention 10 and therefore need not be further described.
Som det vil fremgå af det ovenstående, er montagen af anlægget til korrosionsbeskyttelse meget enkel, da blot holderen 3 skal indskrues i studsen 2, og tilslut-15 ningen 16 til en egnet strømkilde skal udføres, og eventuelt skal der endnu udføres en forbindelse mellem en yderligere fremmedstrømanode, der anbringes på et andet sted i beholderen, og tilslutningen 17.As will be seen from the above, the installation of the corrosion protection system is very simple, since only the holder 3 has to be screwed into the socket 2 and the connection 16 to a suitable power source must be made, and possibly a connection between a a further foreign current anode placed at a different location in the container and the connection 17.
20 Ved udførelsesformen i fig.3er der i gevindstudsen 2 i beholdervæggen 1 indskruet en holder 3b med en passende gevinddel 4b. I holderen 3b er der parallelt med hinanden anbragt en fremmedstrømanode 9b og en referenceelektrode 7b, hvilken sidst er omgivet af et 25 strømningsforhindrende hylster 8b. Det frie endeområde på fremmedstrømanoden 9b er forsynet med et aktiveringsovertræk 19, medens den øvrige del af fremmed-' strømanoden 9b har et oxydationslag, der på grund af sin tyndhed ikke er vist på tegningen. Som særligt 30 egnet materiale til en sådan anode har titan vist sig, idet grundmetallet her passiveres uden yderligere behandling og alene ved en overfladebehandling bliver brugelig til strømgennemgang, ved titan navnlig ved det ovenfor nævnte aktiveringsovertræk 19 af platin.20 In the embodiment of FIG. 3, a holder 3b with a suitable threaded part 4b is screwed into the threaded spigot 2 in the container wall 1. In the holder 3b there is arranged parallel to each other a foreign current anode 9b and a reference electrode 7b, the latter being surrounded by a flow preventing casing 8b. The free end region of the foreign-current anode 9b is provided with an activation coating 19, while the other portion of the foreign-current anode 9b has an oxidation layer which, due to its thinness, is not shown in the drawing. As a particularly suitable material for such an anode, titanium has been found to passivate the base metal here without further treatment and only by a surface treatment becomes usable for current flow, with titanium in particular at the aforementioned platinum activation coating 19.
11 147164 1 På grund, af den beskrevne udformning bevirkes der ved hjælp af det oxydationslag, der er dannet i det overfor referenceelektroden 7b liggende område af frem-medstrømanoden, en passivering eller isolering over-5 for referenceelektroden, så at det enkelte aktive område af fremmedstrømanoden er det med platinovertrækket 19 forsynede område, så at man som resultat med væsentlig mindre indsats opnår samme virkning som ved udførelsesformerne i fig. 1 og 2 ved indlejring af 10 fremmedstrømanoden i et isoleringsstykke, der strækker sig lige så langt som nu oxydationslaget på fremmedstrømanoden .Because of the described embodiment, by means of the oxidation layer formed in the area of the reference electrode 7b facing the reference current anode, a passivation or isolation over the reference electrode is effected so that the individual active region of the the foreign current method is the region provided with the platinum coating 19, so that as a result with substantially less effort, the same effect is obtained as in the embodiments in fig. 1 and 2 by embedding the foreign-current anode in an insulator extending as far as the oxidation layer of the foreign-current anode.
Udførelsesformen i fig. 4 svarer i det væsentlige til 15 udførelsesformen i fig. 3 med undtagelse af, at der findes en metallisk holder 3c, der er udformet som hullegeme, og hvis hulrum 20, der optager fremmedstrømanoden 9c og en referenceelektrode 7c, der er udformet som porøst legeme, eller elektrodens tilledninger, er 20 udfyldt med en isoleringsmasse 21. Endvidere mangler det hylster for referenceelektroden, der findes ved udførelsesformen i fig. 3, da hulrummene i det porøse legeme, der danner referenceelektroden, selv virker strømningsforhindrende. UdføreIsesformen i fig. 4 25 muliggør navnlig en bedre aftætnende forbindelse af den metalliske holder med den metalliske beholdervæg 1 eller dennes fastgørelsesflange 2.The embodiment of FIG. 4 corresponds substantially to the embodiment of FIG. 3 except that there is a metallic holder 3c formed as a hollow body and whose cavity 20 receiving the foreign current anode 9c and a reference electrode 7c formed as a porous body or the leads of the electrode 20 is filled with an insulating mass 21. Furthermore, the sleeve for the reference electrode found in the embodiment of FIG. 3, since the cavities in the porous body forming the reference electrode themselves act as flow inhibitors. The embodiment of FIG. In particular, 4 25 allows a better sealing connection of the metallic holder with the metallic container wall 1 or its fastening flange 2.
De beskrevne udførelsesformer kan ændres på mange må-30 der. F.eks. kan referenceelektroden være udformet i form af en eller flere stave, der strækker sig aksialt i forhold til fremmedstrømanoden, idet der også i dette tilfælde hensigtsmæssigt findes et strømningsforhindrende hylster for referenceelektroden. Porbindel- 12 147164 1 sen mellem beholdervæg og spændingsregulatoren kan naturligvis også udføres uden for holderens hoved.The embodiments described can be changed in many ways. Eg. For example, the reference electrode may be formed in the form of one or more rods which extend axially with respect to the foreign-current method, in which case there is also conveniently a flow-preventing casing for the reference electrode. The pore connection between the container wall and the voltage regulator can of course also be performed outside the head of the holder.
Ved udførelsesformerne i fig. 3 og 4 kan der anvendes 5 en ekstra påsprøjtning af en tynd isolationsfilm på det område af fremmedstrømanoden, der ikke skal forsynes med aktiveringsovertrækket, hvad der navnlig kan komme i betragning ved løvrigt egnede anodematerialer, ved hvilke blot det oxysationslag, der dannes, 10 ikke sikres en tilstrækkelig isolation. Man kan også ved en referenceelektrode, der er udformet som porøst legeme, yderligere anvende et strømningsforhindrende hylster for at være sikker på, at der i alle områder af referenceelektroden, d.v.s. også i elektrodens 15 ydre porøse randområde, sker den mindst mulige strømning.In the embodiments of FIG. 3 and 4, an additional spray of a thin insulating film can be used in the area of the foreign-current anode which is not to be provided with the activation coating, which may be particularly considered for highly suitable anode materials in which only the oxidizing layer formed does not 10 adequate insulation is ensured. In addition, a reference electrode designed as a porous body may further utilize a flow preventive casing to be sure that in all regions of the reference electrode, i.e. also in the outer porous peripheral region of the electrode 15, the least possible flow occurs.
Claims (10)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2605088 | 1976-02-10 | ||
DE2605088A DE2605088C2 (en) | 1976-02-10 | 1976-02-10 | Device for cathodic corrosion protection with impressed current anode |
DE2700943A DE2700943C3 (en) | 1977-01-12 | 1977-01-12 | Device for cathodic corrosion protection with impressed current anode |
DE2700943 | 1977-01-12 |
Publications (3)
Publication Number | Publication Date |
---|---|
DK44977A DK44977A (en) | 1977-08-11 |
DK147164B true DK147164B (en) | 1984-04-30 |
DK147164C DK147164C (en) | 1984-10-15 |
Family
ID=25770028
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DK44977A DK147164C (en) | 1976-02-10 | 1977-02-03 | INSTALLATION FOR CATHODIC CORROSION PROTECTION WITH FOREIGN FLOW ANNEX |
Country Status (9)
Country | Link |
---|---|
AT (1) | AT344816B (en) |
CH (1) | CH625558A5 (en) |
DK (1) | DK147164C (en) |
FR (1) | FR2340994A1 (en) |
GB (1) | GB1527824A (en) |
GR (1) | GR60347B (en) |
IT (1) | IT1079586B (en) |
NL (1) | NL182657C (en) |
SE (1) | SE423822B (en) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2402315A1 (en) * | 1977-08-30 | 1979-03-30 | Mitsubishi Electric Corp | Sealed terminal for metal vessel contg. water - having anticorrosive conductor insulatingly sealed to substrate which is connected to vessel |
DE2946900C2 (en) * | 1979-11-21 | 1982-04-01 | Guldager Electrolyse Gmbh & Co Kg, 4660 Gelsenkirchen-Buer | Container protected against internal corrosion |
DE2946901C2 (en) * | 1979-11-21 | 1982-03-18 | Guldager Electrolyse Gmbh & Co Kg, 4660 Gelsenkirchen-Buer | Vessel cathodically protected against internal corrosion |
IT1253258B (en) | 1991-08-14 | 1995-07-14 | Cgr Di Cadignani Gino | PROCESS OF MAINTENANCE OF A CATHODIC PROTECTION AGAINST CORROSION AND DEVICE FOR THE IMPLEMENTATION OF SUCH PROCESS |
CN111715499A (en) * | 2020-06-16 | 2020-09-29 | 安徽博晟亿电力科技有限公司 | Anti-corrosion treatment method for pig iron casting for railway |
CN113388838A (en) * | 2021-05-23 | 2021-09-14 | 上海赟申船舶工程有限公司 | Suspension type auxiliary anode |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2908623A (en) * | 1957-05-20 | 1959-10-13 | Engelhard Ind Inc | Anode |
US3354061A (en) * | 1963-06-03 | 1967-11-21 | Exxon Research Engineering Co | Method and apparatus for anodic protection |
GB1135056A (en) * | 1965-10-04 | 1968-11-27 | Rank Organisation Ltd | Improvements in or relating to electrode assemblies in cathodic or anodic protection |
DE2358353C3 (en) * | 1973-11-23 | 1981-10-08 | Ruhrgas Ag, 4300 Essen | Device for attaching cathodic protection devices in containers |
-
1977
- 1977-01-24 AT AT41977A patent/AT344816B/en not_active IP Right Cessation
- 1977-02-02 GB GB4192/77A patent/GB1527824A/en not_active Expired
- 1977-02-03 DK DK44977A patent/DK147164C/en not_active IP Right Cessation
- 1977-02-04 SE SE7701239A patent/SE423822B/en unknown
- 1977-02-07 NL NLAANVRAGE7701249,A patent/NL182657C/en not_active IP Right Cessation
- 1977-02-08 GR GR52742A patent/GR60347B/en unknown
- 1977-02-09 CH CH157777A patent/CH625558A5/en not_active IP Right Cessation
- 1977-02-09 IT IT20118/77A patent/IT1079586B/en active
- 1977-02-10 FR FR7703787A patent/FR2340994A1/en active Granted
Also Published As
Publication number | Publication date |
---|---|
SE423822B (en) | 1982-06-07 |
FR2340994B1 (en) | 1980-06-27 |
NL182657C (en) | 1988-04-18 |
SE7701239L (en) | 1977-08-11 |
ATA41977A (en) | 1977-12-15 |
FR2340994A1 (en) | 1977-09-09 |
IT1079586B (en) | 1985-05-13 |
GB1527824A (en) | 1978-10-11 |
NL7701249A (en) | 1977-08-12 |
DK44977A (en) | 1977-08-11 |
AT344816B (en) | 1978-08-10 |
CH625558A5 (en) | 1981-09-30 |
GR60347B (en) | 1978-05-17 |
DK147164C (en) | 1984-10-15 |
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