EP0574064A2 - Method and device for the regulation of corrosion protection installations - Google Patents

Method and device for the regulation of corrosion protection installations Download PDF

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Publication number
EP0574064A2
EP0574064A2 EP93201501A EP93201501A EP0574064A2 EP 0574064 A2 EP0574064 A2 EP 0574064A2 EP 93201501 A EP93201501 A EP 93201501A EP 93201501 A EP93201501 A EP 93201501A EP 0574064 A2 EP0574064 A2 EP 0574064A2
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EP
European Patent Office
Prior art keywords
potential
sacrificial anodes
reference electrode
metal surface
oil tank
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP93201501A
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German (de)
French (fr)
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EP0574064A3 (en
Inventor
Karl Lang
Johan S. Meijer
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GEA Group AG
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Metallgesellschaft AG
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Publication date
Application filed by Metallgesellschaft AG filed Critical Metallgesellschaft AG
Publication of EP0574064A2 publication Critical patent/EP0574064A2/en
Publication of EP0574064A3 publication Critical patent/EP0574064A3/xx
Withdrawn legal-status Critical Current

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    • 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
    • C23F13/04—Controlling or regulating desired parameters
    • 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
    • C23F2213/00—Aspects of inhibiting corrosion of metals by anodic or cathodic protection
    • C23F2213/20—Constructional parts or assemblies of the anodic or cathodic protection apparatus
    • C23F2213/21—Constructional parts or assemblies of the anodic or cathodic protection apparatus combining at least two types of anodic or cathodic protection

Definitions

  • the invention relates to a method and a device for regulating systems for the cathodic corrosion protection of metal surfaces, consisting of a plurality of sacrificial anodes which are electrically conductively connected to one another and at least one electroless reference electrode which are electrically insulated from the metal surface and immersed in the adjacent electrolyte.
  • cathodic corrosion protection with galvanic anodes is used in that the metal to be protected is conductively connected to a metal that is more negative in the electrochemical voltage series. In the galvanic element created in this way, an electrical direct current flows to the more negative metal, which acts as a cathode.
  • Zinc which has a potential of -1100 mV compared to a Cu / CuSO4 measuring cell, has proven particularly useful. It is therefore more negative than the steel with a potential of -600 mV and acts as an anode, polarizes the steel and thereby protects it from corrosion.
  • the potential is reduced by about -200 mV compared to the resting potential, the corrosion is stopped. Steel is protected when the potential is set to around -800 to -850 mV.
  • the zinc anodes are gradually consumed in the cathodic corrosion protection of steel.
  • the solution to this problem is that the potential between the metal surface and the reference electrode is continuously detected by measurement and, in the event of deviations from the desired value of the potential, external current is automatically supplied to the sacrificial anodes until the potential drop is adjusted to the desired potential (setpoint).
  • This method has the advantage that the condition of the cathodic corrosion protection system can be observed at all times and the removal of the sacrificial anodes is kept to a minimum. Otherwise, the material of the anode metal dissolves in uncontrolled operation in accordance with the natural potential difference between the anode and cathode and the resulting corrosion current.
  • the device for carrying out the method consists in that the reference electrode, the output of the sacrificial anodes and the metal surface are connected to a PI controller and the power output of the sacrificial anodes can be regulated.
  • the reference electrode is connected to a PI controller as the actual value.
  • the setpoint set on the PI controller controls a voltage source, which is connected to the sacrificial anodes, in comparison to the actual value.
  • zinc, magnesium, aluminum or iron-silicon alloys are used as sacrificial anodes.
  • a preferred embodiment of the method according to the invention is that instead of the external current supply, the current emitted by the sacrificial anodes is continuously and automatically limited until the potential reduction is brought into line with the desired potential (desired value).
  • the Darlington circuit in which two to three transistors are connected in cascade in such a way that the emitter current of the previous one is equal to the base current of the next transistor, has proven to be particularly suitable for carrying out this method. This significantly increases the current gain and thus the input resistance.
  • an electrically insulated cable (9, 10) is liquid-tight through the wall (11) of the crude oil tank (2) to one with a External power source (12) connected PI controller (13), which is electrically connected to the wall (11) of the crude oil tank (2) via the cable (14).
  • PI controller 13
  • the potential difference between the reference electrode (8) and the crude oil tank (2) is continuously measured regardless of the composition of the water layer (4) and the desired value is supplied by external power supply to the sacrificial anodes the potential difference of approx. -850 mV for steel was kept constant.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Prevention Of Electric Corrosion (AREA)

Abstract

The invention relates to a method for controlling installations for cathodic corrosion protection of metal surfaces, consisting of a plurality of sacrificial anodes which are connected to one another in an electrically conductive manner, and at least one zero-current reference electrode. In order to increase the useful life of the sacrificial anodes, the potential between the metal surface and the reference electrode is continuously measured and, when the potential deviates from the desired value, the sacrificial anodes are automatically fed with external current. <IMAGE>

Description

Die Erfindung betrifft ein Verfahren und eine Vorrichtung zur Regelung von Anlagen für den kathodischen Korrosionsschutz von Metalloberflächen, bestehend aus mehreren elektrisch leitend miteinander verbundenen Opferanoden und wenigstens einer stromlosen Referenzelektrode, die gegenüber der Metalloberfläche elektrisch isoliert sind und in den angrenzenden Elektrolyten eintauchen.The invention relates to a method and a device for regulating systems for the cathodic corrosion protection of metal surfaces, consisting of a plurality of sacrificial anodes which are electrically conductively connected to one another and at least one electroless reference electrode which are electrically insulated from the metal surface and immersed in the adjacent electrolyte.

Wenn Stahl, Eisen, Gußeisen und andere Metalle sowie Legierungen in Erdböden, Süßwasser, Seewasser und sonstigen wäßrigen Elektrolyten in Berührung gebracht werden, erfolgt Korrosion, die in der Ausbildung kleiner galvanischer Korrosionselemente auf der Metalloberfläche begründet ist. Während der Korrosion fließen also im Inneren des Metalls von der anodischen Zone zu der mit ihr im Kurzschluß verbundenen kathodischen Zone der einzelnen galvanischen Korrosionselemente Ströme. Die Korrosion ist mit einem Materialabtrag verbunden, wenn beispielsweise die Elektrolyte Salze enthalten, was gleichbedeutend mit der Abnahme des Elektrolytwiderstands und der Zunahme der Leitfähigkeit ist, die Temperatur des Elektrolyten ansteigt, die Bleche ungleichmäßig mit Walzhaut und/oder Anstrich abgedeckt sind, das Walzgefüge z.B. durch Schweißen verändert wurde, mechanische Spannungen und Inhomogenitäten im Metall vorliegen. Der im einzelnen galvanischen Korrosionselement fließende elektrische Gleichstrom bewirkt an den anodischen Zonen eine Auflösung des Metalls mit den damit verbundenen negativen Folgen.When steel, iron, cast iron and other metals as well as alloys in soil, fresh water, sea water and other aqueous electrolytes are brought into contact, corrosion occurs, which is due to the formation of small galvanic corrosion elements on the metal surface. During corrosion, currents therefore flow inside the metal from the anodic zone to the cathodic zone of the individual galvanic corrosion elements connected to it in the short circuit. Corrosion is associated with material removal if, for example, the electrolytes contain salts, which is synonymous with the decrease in electrolyte resistance and the increase in conductivity, the temperature of the electrolyte rises, the sheets are unevenly covered with rolled skin and / or paint, e.g. the rolled structure was changed by welding, there are mechanical stresses and inhomogeneities in the metal. The electrical direct current flowing in the individual galvanic corrosion element brings about a dissolution of the metal at the anodic zones with the associated negative consequences.

Um solche Korrosion verursachende Gleichströme zu vermeiden, wird der kathodische Korrosionsschutz mit galvanischen Anoden angewendet, indem das zu schützende Metall mit einem in der elektrochemischen Spannungsreihe negativeren Metall leitend verbunden wird. In dem auf diese Weise geschaffenen galvanischen Element fließt ein elektrischer Gleichstrom zum als Kathode wirkenden negativeren Metall.In order to avoid direct currents that cause such corrosion, cathodic corrosion protection with galvanic anodes is used in that the metal to be protected is conductively connected to a metal that is more negative in the electrochemical voltage series. In the galvanic element created in this way, an electrical direct current flows to the more negative metal, which acts as a cathode.

Um beispielsweise den Stahl von Öltanks vor Korrosion zu schützen, ist es erforderlich, ein vergleichsweise negativeres Potential dem Stahl zuzuordnen. Hier hat sich insbesondere Zink bewährt, das ein Potential, gemessen gegenüber einer Cu/CuSO₄-Meßzelle, von -1100 mV besitzt. Es ist also negativer als der Stahl mit einem Potential von -600 mV und wirkt als Anode, polarisiert den Stahl und schützt diesen dadurch vor Korrosion. Die Erfahrungen haben gezeigt, daß bei einer Absenkung des Potentials gegenüber dem Ruhepotential um etwa -200 mV die Korrosion gestoppt wird. Stahl wird geschützt, wenn das Potential auf etwa -800 bis -850 mV eingestellt wird. Die Zinkanoden werden bei dem kathodischen Korrosionsschutz von Stahl allmählich aufgezehrt.To protect the steel of oil tanks from corrosion, for example, it is necessary to assign a comparatively more negative potential to the steel. Zinc, which has a potential of -1100 mV compared to a Cu / CuSO₄ measuring cell, has proven particularly useful. It is therefore more negative than the steel with a potential of -600 mV and acts as an anode, polarizes the steel and thereby protects it from corrosion. Experience has shown that if the potential is reduced by about -200 mV compared to the resting potential, the corrosion is stopped. Steel is protected when the potential is set to around -800 to -850 mV. The zinc anodes are gradually consumed in the cathodic corrosion protection of steel.

Es ist die Aufgabe der vorliegenden Erfindung, das eingangs beschriebene Verfahren so zu verbessern, daß eine kontinuierliche Überwachung kathodischer Korrosionsschutzanlagen für Metalloberflächen möglich ist und die Lebensdauer der Opferanoden deutlich erhöht wird.It is the object of the present invention to improve the method described in the introduction in such a way that continuous monitoring of cathodic corrosion protection systems for metal surfaces is possible and the life of the sacrificial anodes is significantly increased.

Die Lösung dieser Aufgabe besteht darin, daß das Potential zwischen Metalloberfläche und Referenzelektrode fortlaufend durch Messen erfaßt und bei Abweichungen vom gewünschten Wert des Potentials den Opferanoden automatisch Fremdstrom zugeführt wird, bis eine Angleichung der Potentialabsenkung auf das gewünschte Potential (Sollwert) erreicht ist.The solution to this problem is that the potential between the metal surface and the reference electrode is continuously detected by measurement and, in the event of deviations from the desired value of the potential, external current is automatically supplied to the sacrificial anodes until the potential drop is adjusted to the desired potential (setpoint).

Diese Methode hat den Vorteil, daß zu jeder Zeit der Zustand der kathodischen Korrosionsschutzanlage beobachtet werden kann und der Abtrag der Opferanoden auf ein Minimum beschränkt wird. Ansonsten geht im ungeregelten Betrieb der Werkstoff des Anodenmetalls entsprechend dem natürlichen Potentialunterschied zwischen Anode und Kathode und dem daraus resultierenden Korrosionsstrom in Lösung.This method has the advantage that the condition of the cathodic corrosion protection system can be observed at all times and the removal of the sacrificial anodes is kept to a minimum. Otherwise, the material of the anode metal dissolves in uncontrolled operation in accordance with the natural potential difference between the anode and cathode and the resulting corrosion current.

Die Vorrichtung zur Durchführung des Verfahrens besteht darin, daß die Referenzelektrode, der Ausgang der Opferanoden und die Metalloberfläche mit einem PI-Regler verbunden und die Opferanoden in ihrer Stromabgabe regelbar sind.The device for carrying out the method consists in that the reference electrode, the output of the sacrificial anodes and the metal surface are connected to a PI controller and the power output of the sacrificial anodes can be regulated.

Die Referenzelektrode ist auf einen PI-Regler als Ist-Wert geschaltet. Der am PI-Regler eingestellte Soll-Wert steuert im Vergleich zum Ist-Wert eine Spannungsquelle, die mit den Opferanoden verbunden ist.The reference electrode is connected to a PI controller as the actual value. The setpoint set on the PI controller controls a voltage source, which is connected to the sacrificial anodes, in comparison to the actual value.

Als Opferanoden kommen insbesondere solche aus Zink, Magnesium, Aluminium oder Eisen-Silizium-Legierungen zur Anwendung.In particular, zinc, magnesium, aluminum or iron-silicon alloys are used as sacrificial anodes.

Eine vorzugsweise Ausbildung des erfindungsgemäßen Verfahrens besteht darin, daß anstelle der Fremdstromzuführung der von den Opferanoden abgegebene Strom stufenlos automatisch begrenzt wird, bis eine Angleichung der Potentialabsenkung auf das gewünschte Potential (Sollwert) erreicht ist.A preferred embodiment of the method according to the invention is that instead of the external current supply, the current emitted by the sacrificial anodes is continuously and automatically limited until the potential reduction is brought into line with the desired potential (desired value).

Zur Durchführung dieses Verfahrens hat sich die Darlington-Schaltung als besonders geeignet erwiesen, bei der zwei bis drei Transistoren so in Kaskade geschaltet sind, daß der Emitterstrom des vorhergehenden gleich dem Basisstrom des nächstfolgenden Transistors ist. Dadurch werden die Stromverstärkung und damit der Eingangswiderstand wesentlich erhöht.The Darlington circuit, in which two to three transistors are connected in cascade in such a way that the emitter current of the previous one is equal to the base current of the next transistor, has proven to be particularly suitable for carrying out this method. This significantly increases the current gain and thus the input resistance.

Die Erfindung ist nachfolgend mittels den in der Zeichnung dargestellten Figuren näher und beispielhaft erläutert. Es zeigen:

Fig. 1
eine Seitenansicht eines Rohöltanks,
Fig. 2
eine Draufsicht auf einen Rohöltank ohne Dach,
Fig. 3
einen Ausbruch eines Längsschnitts durch den Rohöltank entlang der Linie I-I der Fig. 2.
The invention is explained in more detail below and by way of example using the figures shown in the drawing. Show it:
Fig. 1
a side view of a crude oil tank,
Fig. 2
a top view of a crude oil tank without a roof,
Fig. 3
an outbreak of a longitudinal section through the crude oil tank along the line II of FIG. 2nd

In dem mit Rohöl (1) gefüllten Rohöltank (2) befindet sich zwischen dem kegelförmig ausgebildeten Tankboden (3) und dem Rohöl (1) eine Wasserschicht (4), in die eine im geringen Abstand über dem Tankboden auf sternförmig angebrachten Flacheisenprofilen (5) von der Tankoberfläche elektrisch isoliert aufgelegte, flachschneckenförmig verlaufende Opferanode (6) aus Zink eintaucht. Die elektrische Isolierung erfolgt durch die Opferanode (6) umgebende Kunststoffteile (7). In der Nähe des Tankbodens (3) befindet sich auch eine aus Stahl gegenüber der Tankoberfläche elektrisch isolierte, ebenfalls in die Wasserschicht (4) eintauchende Referenzelektrode (8). Von der Opferanode (6) und der Referenzelektrode (8) ist jeweils ein elektrisch isoliertes Kabel (9,10) flüssigkeitsdicht durch die Wand (11) des Rohöltanks (2) auf einen mit einer Fremdstromquelle (12) verbundenen PI-Regler (13), der über das Kabel (14) elektrisch mit der Wand (11) des Rohöltanks (2) verbunden ist, geführt. Um einen optimalen kathodischen Korrosionsschutz bei einem möglichst geringen Verbrauch an Opferanoden zu erzielen, wird die Potentialdifferenz zwischen der Referenzelektrode (8) und dem Rohöltank (2) unabhängig von der Zusammensetzung der Wasserschicht (4) kontinuierlich gemessen und durch Fremdstromzuleitung auf die Opferanoden der gewünschte Wert der Potentialdifferenz von ca. -850 mV für Stahl konstant gehalten.In the crude oil tank (2) filled with crude oil (1) there is a water layer (4) between the cone-shaped tank bottom (3) and the crude oil (1), into which a flat iron profile (5) is attached at a short distance above the tank bottom. Immersed from the tank surface electrically insulated, flat screw-shaped sacrificial anode (6) made of zinc. Electrical insulation is provided by plastic parts (7) surrounding the sacrificial anode (6). In the vicinity of the tank bottom (3) there is also a reference electrode (8), which is made of steel and is electrically insulated from the tank surface and also plunges into the water layer (4). From the sacrificial anode (6) and the reference electrode (8), an electrically insulated cable (9, 10) is liquid-tight through the wall (11) of the crude oil tank (2) to one with a External power source (12) connected PI controller (13), which is electrically connected to the wall (11) of the crude oil tank (2) via the cable (14). In order to achieve optimal cathodic corrosion protection with the lowest possible consumption of sacrificial anodes, the potential difference between the reference electrode (8) and the crude oil tank (2) is continuously measured regardless of the composition of the water layer (4) and the desired value is supplied by external power supply to the sacrificial anodes the potential difference of approx. -850 mV for steel was kept constant.

Claims (6)

Verfahren zur Regelung von Anlagen für den kathodischen Korrosionsschutz von Metalloberflächen, bestehend aus mehreren elektrisch leitend miteinander verbundenen Opferanoden und wenigstens einer stromlosen Referenzelektrode, die gegenüber der Metalloberfläche elektrisch isoliert sind und in den angrenzenden Elektrolyten eintauchen, dadurch gekennzeichnet, daß das Potential zwischen der Metalloberfläche und der Referenzelektrode fortlaufend durch Messen erfaßt und bei Abweichungen vom gewünschten Wert des Potentials den Opferanoden automatisch Fremdstrom zugeführt wird, bis eine Angleichung der Potentialabsenkung auf das gewünschte Potential (Sollwert) erreicht ist.Method for controlling systems for the cathodic corrosion protection of metal surfaces, consisting of a plurality of sacrificial anodes which are electrically conductively connected to one another and at least one electroless reference electrode which are electrically insulated from the metal surface and immersed in the adjacent electrolyte, characterized in that the potential between the metal surface and the reference electrode is continuously detected by measurement and, in the event of deviations from the desired value of the potential, external current is automatically supplied to the sacrificial anodes until the potential reduction is brought into line with the desired potential (target value). Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1, dadurch gekennzeichnet, daß die Referenzelektrode (8), der Ausgang der Opferanoden (6) und die Metalloberfläche (2) mit einem PI-Regler (13) verbunden und die Opferanoden in ihrer Stromabgabe regelbar sind.Device for carrying out the method according to claim 1, characterized in that the reference electrode (8), the output of the sacrificial anodes (6) and the metal surface (2) are connected to a PI controller (13) and the power output of the sacrificial anodes can be regulated. Anwendung des Verfahrens nach Anspruch 1 auf Öltanks (2) aus Stahlblech, bei denen im geringen Abstand über dem Öltankboden (3) die Opferanoden (6) und die Referenzelektrode (8) angeordnet sind und in die auf dem Öltankboden befindliche Wasserschicht (4) eintauchen.Application of the method according to claim 1 to oil tanks (2) made of sheet steel, in which the sacrificial anodes (6) and the reference electrode (8) are arranged at a short distance above the oil tank bottom (3) and are immersed in the water layer (4) located on the oil tank bottom . Vorrichtung nach Anspruch 3, gekennzeichnet durch flachschneckenförmig mit Abstand über dem Öltankboden (3) aufgelegte Opferanoden (6).Device according to Claim 3, characterized by sacrificial anodes (6) placed flat-screw-shaped at a distance above the oil tank bottom (3). Verfahren zur Regelung von Anlagen für den kathodischen Korrosionsschutz von Metalloberflächen, bestehend aus mehreren elektrisch leitend miteinander verbundenen Opferanoden und wenigstens einer stromlosen Referenzelektrode, die gegenüber der Metalloberfläche elektrisch isoliert sind und in den angrenzenden Elektrolyten eintauchen, dadurch gekennzeichnet, daß das Potential zwischen der Metalloberfläche und der Referenzelektrode fortlaufend durch Messen erfaßt und bei Abweichungen vom gewünschten Wert des Potentials der von den Opferanoden abgegebene Strom stufenlos automatisch begrenzt wird, bis eine Angleichung der Potentialabsenkung auf das gewünschte Potential (Sollwert) erreicht ist.Method for controlling systems for the cathodic protection against corrosion of metal surfaces, consisting of several sacrificial anodes which are electrically conductively connected to one another and at least one electroless reference electrode, which are electrically insulated from the metal surface and immersed in the adjacent electrolyte, characterized in that the potential between the metal surface and the reference electrode is continuously detected by measurement and, in the event of deviations from the desired value of the potential, the current emitted by the sacrificial anodes is continuously and automatically limited until the potential reduction is brought into line with the desired potential (setpoint). Vorrichtung nach Anspruch 5, gekennzeichnet durch die Verwendung einer Darlington-Schaltung.Apparatus according to claim 5, characterized by the use of a Darlington circuit.
EP93201501A 1992-06-12 1993-05-26 Method and device for the regulation of corrosion protection installations Withdrawn EP0574064A2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE4219202 1992-06-12
DE4219202 1992-06-12
DE4314924A DE4314924A1 (en) 1992-06-12 1993-05-06 Method and device for controlling corrosion protection systems
DE4314924 1993-05-06

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Publication Number Publication Date
EP0574064A2 true EP0574064A2 (en) 1993-12-15
EP0574064A3 EP0574064A3 (en) 1994-02-16

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EP93201501A Withdrawn EP0574064A2 (en) 1992-06-12 1993-05-26 Method and device for the regulation of corrosion protection installations

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EP (1) EP0574064A2 (en)
DE (1) DE4314924A1 (en)
MX (1) MX9303487A (en)
NO (1) NO932156L (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2286196A (en) * 1994-01-27 1995-08-09 John Crome Latham Protecting vessels from corrosion using sacrificial anodes to carry impressed current
GB2481104A (en) * 2010-05-31 2011-12-14 Corrosion Service Company Ltd Apparatus and method for providing corrosion protection to a stainless steel process vessel

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1521246A1 (en) * 1965-12-30 1969-07-24 Bayer Ag Process and circuit for the protection of metallic surfaces against chemical metallization
DE8709159U1 (en) * 1987-07-03 1987-08-13 Schuss, Gunter, 3560 Biedenkopf, De
DE3716081A1 (en) * 1986-01-28 1988-11-24 Gunter Schuss Device for continuously providing a corrosion protection in a steel-sheet heating-oil storage container
US5065893A (en) * 1991-03-15 1991-11-19 Corrpro Companies Inc. Cathodic protection system and method for above-ground storage tank bottoms

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1521246A1 (en) * 1965-12-30 1969-07-24 Bayer Ag Process and circuit for the protection of metallic surfaces against chemical metallization
DE3716081A1 (en) * 1986-01-28 1988-11-24 Gunter Schuss Device for continuously providing a corrosion protection in a steel-sheet heating-oil storage container
DE8709159U1 (en) * 1987-07-03 1987-08-13 Schuss, Gunter, 3560 Biedenkopf, De
US5065893A (en) * 1991-03-15 1991-11-19 Corrpro Companies Inc. Cathodic protection system and method for above-ground storage tank bottoms

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2286196A (en) * 1994-01-27 1995-08-09 John Crome Latham Protecting vessels from corrosion using sacrificial anodes to carry impressed current
GB2481104A (en) * 2010-05-31 2011-12-14 Corrosion Service Company Ltd Apparatus and method for providing corrosion protection to a stainless steel process vessel
US8608913B2 (en) 2010-05-31 2013-12-17 Corrosion Service Company Limited Method and apparatus for providing electrochemical corrosion protection
GB2481104B (en) * 2010-05-31 2014-04-23 Corrosion Service Company Ltd Method and apparatus for providing electrochemical corrosion protection

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Publication number Publication date
EP0574064A3 (en) 1994-02-16
NO932156L (en) 1993-12-13
MX9303487A (en) 1994-07-29
DE4314924A1 (en) 1993-12-16
NO932156D0 (en) 1993-06-11

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