CA1046455A - Electrolytic treating apparatus - Google Patents
Electrolytic treating apparatusInfo
- Publication number
- CA1046455A CA1046455A CA228,886A CA228886A CA1046455A CA 1046455 A CA1046455 A CA 1046455A CA 228886 A CA228886 A CA 228886A CA 1046455 A CA1046455 A CA 1046455A
- Authority
- CA
- Canada
- Prior art keywords
- strip
- electrodes
- cross
- current
- electrode
- Prior art date
- 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.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F1/00—Electrolytic cleaning, degreasing, pickling or descaling
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
- C25F7/00—Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects; Servicing or operating
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electroplating Methods And Accessories (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An electrolytic treating apparatus employing the princi-ple of high-current density by-polar electrolyzing, wherein the current is conducted from the electrodes through the electrolyte to the metal strip being treated. The efficiency of the resulting elec-trolyzing treatment is enhanced by employing (a) electrodes of a generally circular cross-section and (b) offset electrode position-ing, so that the electrodes facing the top surface of the strip do not overlie the electrodes facing the bottom surface of the strip.
An electrolytic treating apparatus employing the princi-ple of high-current density by-polar electrolyzing, wherein the current is conducted from the electrodes through the electrolyte to the metal strip being treated. The efficiency of the resulting elec-trolyzing treatment is enhanced by employing (a) electrodes of a generally circular cross-section and (b) offset electrode position-ing, so that the electrodes facing the top surface of the strip do not overlie the electrodes facing the bottom surface of the strip.
Description
:. ~.04~55 : This invention relates to an apparatus for the high current density electrotreating (pickling, cleaning, etc.) of metal strip and is more particularly related to improvement in electrode positioning and construction.
Virtually all production of continuous lengths of metal strip results in undesirable resiclues remaining on the surface of ~ the strip. Such residues may, for example, be oxides which are ; generally removed by pickling in acid, or lubricants which are r - rcmoved by cleaning in alkaline detergents. When the end uses of the strip require a particularly clean surface (eg. when the metal - is to be coated as in tin-plate) the art often resorts to electrolytic processes which, in general, provide for more ` effective residue removal. Presently, the electrolytic treatment of continuously moving metal strip is accomplished by passing the ., .
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- strip between electrodes having a generally rectangular cross-- section. Current transfer to the strip is achieved by either of two basic means:
,:
. (1) use of conductor rolls, etc. for making direct electrical contact with the strip, or
Virtually all production of continuous lengths of metal strip results in undesirable resiclues remaining on the surface of ~ the strip. Such residues may, for example, be oxides which are ; generally removed by pickling in acid, or lubricants which are r - rcmoved by cleaning in alkaline detergents. When the end uses of the strip require a particularly clean surface (eg. when the metal - is to be coated as in tin-plate) the art often resorts to electrolytic processes which, in general, provide for more ` effective residue removal. Presently, the electrolytic treatment of continuously moving metal strip is accomplished by passing the ., .
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- strip between electrodes having a generally rectangular cross-- section. Current transfer to the strip is achieved by either of two basic means:
,:
. (1) use of conductor rolls, etc. for making direct electrical contact with the strip, or
(2) transfer of current flow from an electrode of one polarity, through the electrolyte to the strip and again through the electrolyte to an electrode of opposite polarity. Since the : ;
danger of sparking at contact points between the strip and rolls ; 10 increases as the current density employed increases, the latter ; method, which is sometimes referred to as bi-polar electrolyzing -has been found especially beneficial (see, for example, U.S.
Patent 3,338,809) for electrolytic treatments employing very high . current densities. Although not directed to the use of very high .. . .
;~ densities, U.S. Patent 2,165,326, shows an electrotreating cell 'i which may be employed for effecting bi-polar electrolyzing.
However, if such a cell is employed for the electrolytic treat-ment of metal strip at very high current densities, i.e. in excess o about 500 Amps/ft2. and, ~ore desirably within the range 2000-~ . ., 10,000 Amps/ft2, it is found that current efficiency is markedly ` decreased as a result of large losses within the electrolyte itself. Additionally, it has been found, even when employing ~;; bi-polar electrolyzing, that such very high current densities .~.
- nevertheless often give rise to arcing and other problems associated with stray currents, such as overheated bearings.
,;..::
Therefore this invention provides an apparatus useful for the bi-polar electrolyzing of metal strip and which is - capable of achieving significantly enhanced current efficiencies.
The apparatus utilizes particular electrode configurations and connections for minimizing the deleterious :;
`i` effects of stray currents.
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~ ~09~55 Accordingly, there is provided by means of this invention an apparatus for the electrolytic treatment of metal strip within an electrolyte bath, which includes means for guiding the strip ~ .
in a substantially horizontal p:Lane, through the bath. There is provided a number, n, of electrode pair configurations, n being at least 2. Each of the electrodes is elongate and extends ` transversely of the strip. The electrodes forming each of the said pairs are i) in an electrotreating position, ii) on opposite sides of the metal strip, ~:; iii) offset from each other so that the distance .. .
~ between their respective vertical cross-. . . , , ~
. sectional axes is greater than the sum of - their effective cross-sectional widths/2, and iv) the portion of that elongate electrode facing the top surface of the strip exhibits ,-:~. ................................................................. - .
;~ a convex cross-section.
: . .
A d-c source of EMF supplies a current density within ; the range of 500 to 10,000 Amps/ft2 to the strip and the source -~ 20 is connected so as to make the electrodes in each pair , -;
approximately the same potential and of a polarity opposite to that of the pair configurations adjacent thereto. Separating each of the electrode pair configurations are insulative baffles positioned for the unencumbered passage of the strip, whereby the major portion of the current passing between oppositely charged electrodes is caused to flow through the strip.
The above and other advantages of the present invention will be more apparent from the following description when taken in conjunction with the appended claims and drawing, in which:
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. . . ~, 1~ 5 ; The figure is a diagrammatic representation of a longitudinal cross-section of the apparatus, illustrating the `~ essential features of this invention.
Referring to the Figure, the apparatus consists of a tank 2, containing an electrolyte (not shown) suitable for the ~; contemplated electrolytic treatment. The metal strip 3, is ; passed in a substantially horizontal plane, through non-conductive bumper rolls 4a, into the tank and ~etween electrode ~` pair configurations 5a - 5b, 6a - 6b, and 7a - 7b, respectively, The electrodes are oriented in a conventional electrotreating .:
~ position; that is, their longitudinal axes (i) lie in a segment :..:
of a plane which is parallel to the plane segment formed by ., .
` ~ the strip face and (ii) are generally perpendicular to the -~ direction of strip travel. On exiting the tank, the strip is again passed through bumper rolls 4b, placed somewhat closer to the strip than the electrodes themselves. Such bumper ., .
~ rolls, which also act as guide rolls, serve to prevent '~,'. '.: , !
undesirable contact of the strip with the electrodes. Their use is especially desirable in commercial prac*ice, where a high rate .; i~.
of strip travel (increased vibration) and poor strip shape i (waviness) would both combine to make such undesirable contact a virtual certainty. Plastic pipe bumpers 8 may also be placed within the tank to provide additional insurance against such undesirable contact. In addition to the use of bumpers, -` ~ however, it is a . .
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feature of this invention to preFerably employ an odd number _, of electrode pair configurations. Three such pair configurations are illustrated, but it should be understood that 5, 7, etc. such configurations may be employed, as well. In using such an odd number of electrode pair configurations, it has been fou~d that the deleterious effects of stray currents are to a substantial extent - eliminated, thereby further reducing the tendency to arcing and/or strip burns, attendant in the use of very high current densities.
In employing an odd number of electrode pair configurations, it is desirable that the cross-sectional area of the positively charged -` electrodes be approximately equal to that of the negatively charged electrodes. This factor is illustrated in the figure, wherein the - negatively charged electrodes 6a - 6b, are of a greater cross-section and are therefore each capable of concucting a greater : :
amount of current than any of the individual positively charged electrodes.
Three features for improving current efficiency are also ." , shown in the figure:
- (a) In contrast with electrodes conventionally employed 20 in treating strip, it is essential that the portion of the electrodes facing the top surface of the strip exhibit a convex shape and preferably be of a generally semi-circ~lar shape. For ease of constructi~on, it will generally be most practical to produce cylindrical electrodes, i.e. electrodes with a circular cross-,.
section, as shown in the figure. It should he understood, however, ~ that the portion of the electrodes not facing the strip, ie., the ;~ top portions of electrodes 5a, 6a and 7a may, for example, be flat.
Similarly, the shape of the bottom electrodes is not critical and . .
.
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104f~S5 conventional electrodes of rectarlyular cross-section may be employed.
In actua:L practice a large number of electrodes will be produced at one time. In order that the electrodes may be interchangeable it will generally be preferable to employ bottom electrodes 5b, 6b, 7b which are similarly of a generally cylindrical shape.
The enhanced current efficiency, resulting from the use of top electrodes of circular cross-section, is showm in Table I.
Ferrous metal strip having an oxide coating thereon, was electro-pickled in 20~ H2SO4 solution maintained at a temperature of 125E.
- 10 The distance from both the top and bottom electrodes, to the strip, was 1.5 inches, for all runs. The strip was passed at the same ; speed in all cases to provide an electrolyzing period of three seconds. The data is an average of four samples, whereby the reported current efficiencies were determined by measuring the amount of scale removed (pic~led) from the strip surface. The ;- beneficial effect of round electrodes is readily seen; this effect tending to increase with an increase in current density. For the data of this Table 1, the electrodes were offset from each other as shown in the figure.
~ Table I
High Current Density Pickling Efficiency - Electrodes of rectangular vs. circular cross-section ., , - Pickling ~fficiency-~
Current 2 Rectangular Circular Efficiency Density-Amps/ft Electrode Electrode Increase-~
6,666 52 59 13.5 8,333 64 77 20.3 10,000 77 93 20.8 . .
(b) It is seen, with respect to any electrode pair configuration; for example 5a-5b, that contrary to conventional .:.
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placements, top electrode 5a does not overlie electrode 5b. It has been found that additional enhancement of efficiency may be achieved if the electrodes forming a pair configuxation do not so overlie one `- another. Stated another way, if we imagine a vertical axis drawn through both the top and bottom electrodes, then the distance ...... .
between these two axes should be greater than the sum of the cross-;.
sectional widths of both eelctrodes, divided by 2. In the specific case where round electrodes are employed, then the distance between - the vertical axes should be greater than: the sum of the diameters of both electrodes divided by 2 (i.e. greater than the sum of the - two radii). The beneficial effect of such electrode offset is shown : ~ .
; in Table II. Unless otherwise stated, electrolyzing conditions were the same as above. However, utilizing the knowledge gleaned from the data of Table I, only round electrodes were evaluated in the - 15 runs below.
:
Table II
High Current Density Picklinq Efficiency ; ~ -~- Overlying Electrodes vs. Offset Electrodes Pickliny Efficiency-%
~ 20 Current OverlyingOffset Efficiency .`- Density-Amps/ft2 ElectrodesElectrodesIncrease-%
.: ;.
5,000 31 35 12.9 6,666 46 58 26.1 8,333 66 78 18.2 ~ (~) Separating the respective electrode pair configura--~` tions are insulative baffles 9 for directing the current through ~ 25 i; the strip. These baffles, which may, for example, be made of ~ polypropylene, are positioned a short distance Erom the strip sur-; face, but nevertheless sufficient ~o that the passage of the strip therethrough is not encumbered. Since a significant portion of the ,.... . .
r. ' ~ 6 -~, . .
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... ",. ~ .
~04G~S5 current would tend to travel in a straight line between the electrodes (eg. a line between 5a and 6a) it may be seen that the baffles serve to block that route, and force that otherwifie lost current through the strip. It is therefore desirable that the ., ;~,J'.' 5 baffles be sufficiently close to the strip 50 as to cause a substantial portion of the current which would norm~lly travel in such straight lines, to be diverted therefrom and travel through the strip tsee the dashed lines of thè Figure).
~, In addition to the above noted features for improving current efficiency, it is nevertheless desirable that the effects ; of concentration polarization be reduced by employing any of the .
well known techniques for effecting stirring of the solution? For example, simple mechanical or propellor-type stirrers may be emplo-yed. Particularly good results have been achieved through the use ~ 15 of flow headers 10 (driven by a circulation pump not shown) which - force a bw pressure jet of electrolyte toward the strip face at a small angle, e.g. 30. Even when current densities within the range 2000 - 10,000 Amps/ft2 are employed, it has been found that stirring of the electrolyte need not be particularly turbulent, . . .
especially if the flow headers are strategically positioned, as shown, near those portions of the strip surfaces undergoing maximum : -electrochemical activity.
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danger of sparking at contact points between the strip and rolls ; 10 increases as the current density employed increases, the latter ; method, which is sometimes referred to as bi-polar electrolyzing -has been found especially beneficial (see, for example, U.S.
Patent 3,338,809) for electrolytic treatments employing very high . current densities. Although not directed to the use of very high .. . .
;~ densities, U.S. Patent 2,165,326, shows an electrotreating cell 'i which may be employed for effecting bi-polar electrolyzing.
However, if such a cell is employed for the electrolytic treat-ment of metal strip at very high current densities, i.e. in excess o about 500 Amps/ft2. and, ~ore desirably within the range 2000-~ . ., 10,000 Amps/ft2, it is found that current efficiency is markedly ` decreased as a result of large losses within the electrolyte itself. Additionally, it has been found, even when employing ~;; bi-polar electrolyzing, that such very high current densities .~.
- nevertheless often give rise to arcing and other problems associated with stray currents, such as overheated bearings.
,;..::
Therefore this invention provides an apparatus useful for the bi-polar electrolyzing of metal strip and which is - capable of achieving significantly enhanced current efficiencies.
The apparatus utilizes particular electrode configurations and connections for minimizing the deleterious :;
`i` effects of stray currents.
~:, ~ -2-:::
;''','.''; -'i,~ .
,, ~
:: .
.... . ..
. .: . .
~- - .
~ ~09~55 Accordingly, there is provided by means of this invention an apparatus for the electrolytic treatment of metal strip within an electrolyte bath, which includes means for guiding the strip ~ .
in a substantially horizontal p:Lane, through the bath. There is provided a number, n, of electrode pair configurations, n being at least 2. Each of the electrodes is elongate and extends ` transversely of the strip. The electrodes forming each of the said pairs are i) in an electrotreating position, ii) on opposite sides of the metal strip, ~:; iii) offset from each other so that the distance .. .
~ between their respective vertical cross-. . . , , ~
. sectional axes is greater than the sum of - their effective cross-sectional widths/2, and iv) the portion of that elongate electrode facing the top surface of the strip exhibits ,-:~. ................................................................. - .
;~ a convex cross-section.
: . .
A d-c source of EMF supplies a current density within ; the range of 500 to 10,000 Amps/ft2 to the strip and the source -~ 20 is connected so as to make the electrodes in each pair , -;
approximately the same potential and of a polarity opposite to that of the pair configurations adjacent thereto. Separating each of the electrode pair configurations are insulative baffles positioned for the unencumbered passage of the strip, whereby the major portion of the current passing between oppositely charged electrodes is caused to flow through the strip.
The above and other advantages of the present invention will be more apparent from the following description when taken in conjunction with the appended claims and drawing, in which:
, ,;. ., ;~ ' ".,~ ~ .
;~ -3-.:
~,",~
. . . ~, 1~ 5 ; The figure is a diagrammatic representation of a longitudinal cross-section of the apparatus, illustrating the `~ essential features of this invention.
Referring to the Figure, the apparatus consists of a tank 2, containing an electrolyte (not shown) suitable for the ~; contemplated electrolytic treatment. The metal strip 3, is ; passed in a substantially horizontal plane, through non-conductive bumper rolls 4a, into the tank and ~etween electrode ~` pair configurations 5a - 5b, 6a - 6b, and 7a - 7b, respectively, The electrodes are oriented in a conventional electrotreating .:
~ position; that is, their longitudinal axes (i) lie in a segment :..:
of a plane which is parallel to the plane segment formed by ., .
` ~ the strip face and (ii) are generally perpendicular to the -~ direction of strip travel. On exiting the tank, the strip is again passed through bumper rolls 4b, placed somewhat closer to the strip than the electrodes themselves. Such bumper ., .
~ rolls, which also act as guide rolls, serve to prevent '~,'. '.: , !
undesirable contact of the strip with the electrodes. Their use is especially desirable in commercial prac*ice, where a high rate .; i~.
of strip travel (increased vibration) and poor strip shape i (waviness) would both combine to make such undesirable contact a virtual certainty. Plastic pipe bumpers 8 may also be placed within the tank to provide additional insurance against such undesirable contact. In addition to the use of bumpers, -` ~ however, it is a . .
'''.'.~
, . .
:.
'`';
,:,.,~
.:
,..
-., ;
; ....
; -3a-, ~ ,. . .
,........ . ..
,;:
: :i ~ .::
1044~45S
feature of this invention to preFerably employ an odd number _, of electrode pair configurations. Three such pair configurations are illustrated, but it should be understood that 5, 7, etc. such configurations may be employed, as well. In using such an odd number of electrode pair configurations, it has been fou~d that the deleterious effects of stray currents are to a substantial extent - eliminated, thereby further reducing the tendency to arcing and/or strip burns, attendant in the use of very high current densities.
In employing an odd number of electrode pair configurations, it is desirable that the cross-sectional area of the positively charged -` electrodes be approximately equal to that of the negatively charged electrodes. This factor is illustrated in the figure, wherein the - negatively charged electrodes 6a - 6b, are of a greater cross-section and are therefore each capable of concucting a greater : :
amount of current than any of the individual positively charged electrodes.
Three features for improving current efficiency are also ." , shown in the figure:
- (a) In contrast with electrodes conventionally employed 20 in treating strip, it is essential that the portion of the electrodes facing the top surface of the strip exhibit a convex shape and preferably be of a generally semi-circ~lar shape. For ease of constructi~on, it will generally be most practical to produce cylindrical electrodes, i.e. electrodes with a circular cross-,.
section, as shown in the figure. It should he understood, however, ~ that the portion of the electrodes not facing the strip, ie., the ;~ top portions of electrodes 5a, 6a and 7a may, for example, be flat.
Similarly, the shape of the bottom electrodes is not critical and . .
.
;~ - 4 -,,. :
~.
'': ~ ~ '' ' ~ ' ' , . ' ' :
., ~ . '' ~ ;
104f~S5 conventional electrodes of rectarlyular cross-section may be employed.
In actua:L practice a large number of electrodes will be produced at one time. In order that the electrodes may be interchangeable it will generally be preferable to employ bottom electrodes 5b, 6b, 7b which are similarly of a generally cylindrical shape.
The enhanced current efficiency, resulting from the use of top electrodes of circular cross-section, is showm in Table I.
Ferrous metal strip having an oxide coating thereon, was electro-pickled in 20~ H2SO4 solution maintained at a temperature of 125E.
- 10 The distance from both the top and bottom electrodes, to the strip, was 1.5 inches, for all runs. The strip was passed at the same ; speed in all cases to provide an electrolyzing period of three seconds. The data is an average of four samples, whereby the reported current efficiencies were determined by measuring the amount of scale removed (pic~led) from the strip surface. The ;- beneficial effect of round electrodes is readily seen; this effect tending to increase with an increase in current density. For the data of this Table 1, the electrodes were offset from each other as shown in the figure.
~ Table I
High Current Density Pickling Efficiency - Electrodes of rectangular vs. circular cross-section ., , - Pickling ~fficiency-~
Current 2 Rectangular Circular Efficiency Density-Amps/ft Electrode Electrode Increase-~
6,666 52 59 13.5 8,333 64 77 20.3 10,000 77 93 20.8 . .
(b) It is seen, with respect to any electrode pair configuration; for example 5a-5b, that contrary to conventional .:.
_ 5 _ ,,; .
: , , ., . . , , . .
'.- ,'.: . ~: ', ::. ., . -.;:~ . .~ . :
:: . , ;
` 1~46~S
placements, top electrode 5a does not overlie electrode 5b. It has been found that additional enhancement of efficiency may be achieved if the electrodes forming a pair configuxation do not so overlie one `- another. Stated another way, if we imagine a vertical axis drawn through both the top and bottom electrodes, then the distance ...... .
between these two axes should be greater than the sum of the cross-;.
sectional widths of both eelctrodes, divided by 2. In the specific case where round electrodes are employed, then the distance between - the vertical axes should be greater than: the sum of the diameters of both electrodes divided by 2 (i.e. greater than the sum of the - two radii). The beneficial effect of such electrode offset is shown : ~ .
; in Table II. Unless otherwise stated, electrolyzing conditions were the same as above. However, utilizing the knowledge gleaned from the data of Table I, only round electrodes were evaluated in the - 15 runs below.
:
Table II
High Current Density Picklinq Efficiency ; ~ -~- Overlying Electrodes vs. Offset Electrodes Pickliny Efficiency-%
~ 20 Current OverlyingOffset Efficiency .`- Density-Amps/ft2 ElectrodesElectrodesIncrease-%
.: ;.
5,000 31 35 12.9 6,666 46 58 26.1 8,333 66 78 18.2 ~ (~) Separating the respective electrode pair configura--~` tions are insulative baffles 9 for directing the current through ~ 25 i; the strip. These baffles, which may, for example, be made of ~ polypropylene, are positioned a short distance Erom the strip sur-; face, but nevertheless sufficient ~o that the passage of the strip therethrough is not encumbered. Since a significant portion of the ,.... . .
r. ' ~ 6 -~, . .
.~. .",. , . i,.~ , .
~, ` ' '~ ' ' : -:"`~'': :. . ' , :
.... . . . . .
~: .. . . . . . .
... ",. ~ .
~04G~S5 current would tend to travel in a straight line between the electrodes (eg. a line between 5a and 6a) it may be seen that the baffles serve to block that route, and force that otherwifie lost current through the strip. It is therefore desirable that the ., ;~,J'.' 5 baffles be sufficiently close to the strip 50 as to cause a substantial portion of the current which would norm~lly travel in such straight lines, to be diverted therefrom and travel through the strip tsee the dashed lines of thè Figure).
~, In addition to the above noted features for improving current efficiency, it is nevertheless desirable that the effects ; of concentration polarization be reduced by employing any of the .
well known techniques for effecting stirring of the solution? For example, simple mechanical or propellor-type stirrers may be emplo-yed. Particularly good results have been achieved through the use ~ 15 of flow headers 10 (driven by a circulation pump not shown) which - force a bw pressure jet of electrolyte toward the strip face at a small angle, e.g. 30. Even when current densities within the range 2000 - 10,000 Amps/ft2 are employed, it has been found that stirring of the electrolyte need not be particularly turbulent, . . .
especially if the flow headers are strategically positioned, as shown, near those portions of the strip surfaces undergoing maximum : -electrochemical activity.
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Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An apparatus for the electrolytic treatment of metal strip within an electrolyte bath, comprising:
(a) means for guiding said strip in a substantially horizontal plane, through said bath, (b) a number, n, of electrode pair configurations, n being at least 2, each of said electrodes being elongate and extending transversely to the strip, the electrodes forming each of said pairs being, (i) in an electrotreating position, (ii) on opposite sides of the metal strip, (iii) offset from each other so that the distance between their respective vertical cross-sectional axes is greater than the sum of their effective cross-sectional widths/2, and (iv) the portion of that elongate electrode facing the top surface of the strip, exhibiting a convex cross-section, (c) a d-c source of EMF, adapted to supply a current density within the range of 500 to 10,000 Amps/ft2 to said strip, and connected so as to make the electrodes in each pair approximately the same potential and of a polarity opposite to that of the pair configurations adjacent thereto; and (d) separating each said pair configuration, insulative baffles positioned for the unencumbered passage of said strip, whereby the major portion of the current passing between oppositely charged electrodes is caused to flow through the strip.
(a) means for guiding said strip in a substantially horizontal plane, through said bath, (b) a number, n, of electrode pair configurations, n being at least 2, each of said electrodes being elongate and extending transversely to the strip, the electrodes forming each of said pairs being, (i) in an electrotreating position, (ii) on opposite sides of the metal strip, (iii) offset from each other so that the distance between their respective vertical cross-sectional axes is greater than the sum of their effective cross-sectional widths/2, and (iv) the portion of that elongate electrode facing the top surface of the strip, exhibiting a convex cross-section, (c) a d-c source of EMF, adapted to supply a current density within the range of 500 to 10,000 Amps/ft2 to said strip, and connected so as to make the electrodes in each pair approximately the same potential and of a polarity opposite to that of the pair configurations adjacent thereto; and (d) separating each said pair configuration, insulative baffles positioned for the unencumbered passage of said strip, whereby the major portion of the current passing between oppositely charged electrodes is caused to flow through the strip.
2. The apparatus of claim 1, in which said electrode portions exhibiting a convex cross-section are substantially semicircular, and said current density is at least 2000 Amps/ft2.
3. The apparatus of claim 2, in which n is an odd number.
4. The apparatus of claim 3, in which the electrodes above said substantially horizontal plane are of a generally cylindrical shape.
5. The apparatus of claim 4, in which all the electrodes are of a generally cylindrical shape.
6. The apparatus of claim 5, in which the cross-sectional area of all positively charged electrodes is approximately equal to the cross-sectional area of all negatively charged electrodes.
7. The apparatus of claim 6, including electrolyte flow headers for increasing solution turbulence near those portions of the strip surfaces undergoing maximum electrochemical activity, whereby concentration polarization is decreased at least to an extent sufficient to support current densities within said range.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US542757*A US3926767A (en) | 1975-01-21 | 1975-01-21 | Electrolytic treating apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1046455A true CA1046455A (en) | 1979-01-16 |
Family
ID=24165160
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA228,886A Expired CA1046455A (en) | 1975-01-21 | 1975-06-09 | Electrolytic treating apparatus |
Country Status (25)
| Country | Link |
|---|---|
| US (1) | US3926767A (en) |
| JP (1) | JPS5839920B2 (en) |
| AR (2) | AR204283A1 (en) |
| AU (1) | AU497402B2 (en) |
| BE (1) | BE831547A (en) |
| BG (1) | BG25382A3 (en) |
| BR (1) | BR7504688A (en) |
| CA (1) | CA1046455A (en) |
| CS (1) | CS187485B2 (en) |
| DE (1) | DE2533319A1 (en) |
| ES (1) | ES439706A1 (en) |
| FR (1) | FR2298620A1 (en) |
| GB (1) | GB1455989A (en) |
| HU (1) | HU175188B (en) |
| IN (1) | IN142422B (en) |
| IT (1) | IT1041317B (en) |
| NL (1) | NL182329C (en) |
| PH (1) | PH12125A (en) |
| PL (1) | PL105800B1 (en) |
| RO (1) | RO68080A (en) |
| SE (1) | SE413039B (en) |
| SU (1) | SU609480A3 (en) |
| TR (1) | TR18385A (en) |
| YU (1) | YU39946B (en) |
| ZA (1) | ZA754166B (en) |
Families Citing this family (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BG22251A1 (en) * | 1974-10-04 | 1979-12-12 | Petrov | Method and installation for non-ferros elektrolysis |
| JPS5548422A (en) * | 1978-09-21 | 1980-04-07 | Sumitomo Metal Ind Ltd | Electrolytic descaling method by indirect electrification system of steel wire rod and its device |
| US4214961A (en) * | 1979-03-01 | 1980-07-29 | Swiss Aluminium Ltd. | Method and apparatus for continuous electrochemical treatment of a metal web |
| JPS56133495A (en) * | 1980-03-19 | 1981-10-19 | Toshiba Corp | Electrolytic working device |
| DE3017079A1 (en) * | 1980-05-03 | 1981-11-05 | Thyssen AG vorm. August Thyssen-Hütte, 4100 Duisburg | DEVICE FOR ELECTROPLATING |
| DE3023827C2 (en) * | 1980-06-25 | 1985-11-21 | Siemens AG, 1000 Berlin und 8000 München | Plant for the galvanic deposition of aluminum |
| US4391685A (en) * | 1981-02-26 | 1983-07-05 | Republic Steel Corporation | Process for electrolytically pickling steel strip material |
| US4363709A (en) * | 1981-02-27 | 1982-12-14 | Allegheny Ludlum Steel Corporation | High current density, acid-free electrolytic descaling process |
| JPS58107498A (en) * | 1981-12-18 | 1983-06-27 | Fuji Photo Film Co Ltd | Method and apparatus for electrolytic treatment of strip like metal plate |
| SE429765B (en) * | 1982-02-09 | 1983-09-26 | Jouko Korpi | SET ON ELECTROPLETING |
| JPS62250197A (en) * | 1986-04-21 | 1987-10-31 | Taisho Kogyo Kk | Plating device |
| JPS6339179U (en) * | 1986-09-01 | 1988-03-14 | ||
| DE3703769A1 (en) * | 1987-02-07 | 1988-08-18 | Schempp & Decker Maschinenbau | Device for electroplating a metal strip |
| US5087342A (en) * | 1988-04-07 | 1992-02-11 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| US4935112A (en) * | 1988-04-07 | 1990-06-19 | Seneca Wire And Manufacturing Company | Continuous steel strand electrolytic processing |
| DE3934683A1 (en) * | 1989-10-18 | 1991-04-25 | Kurt Hausmann | METHOD AND DEVICE FOR ELECTROCHEMICALLY Roughening A METAL SURFACE |
| US5164033A (en) * | 1990-04-17 | 1992-11-17 | Tir Systems Ltd. | Electro-chemical etch device |
| SE469267B (en) * | 1991-07-01 | 1993-06-14 | Candor Sweden Ab | Surface treatment device, whereby a medium under pressure is aimed at a continuous material web in a cavity |
| DE4425854C1 (en) * | 1994-07-07 | 1995-11-09 | Mannesmann Ag | Electrolytic surface treatment process and plant for carrying out the process |
| AT405060B (en) * | 1996-04-12 | 1999-05-25 | Andritz Patentverwaltung | METHOD AND DEVICE FOR ELECTROLYTICALLY TREATING CONTINUOUS GOODS |
| SE511777C2 (en) * | 1998-02-02 | 1999-11-22 | Avesta Sheffield Ab | Method of processing a metal product |
| FI108115B (en) * | 1998-11-05 | 2001-11-30 | Outokumpu Oy | Apparatus for treating a metal surface |
| DE19951325C2 (en) * | 1999-10-20 | 2003-06-26 | Atotech Deutschland Gmbh | Method and device for the electrolytic treatment of electrically insulated, electrically conductive structures on surfaces of electrically insulating film material and applications of the method |
| US6495005B1 (en) * | 2000-05-01 | 2002-12-17 | International Business Machines Corporation | Electroplating apparatus |
| SE519159C2 (en) * | 2000-10-20 | 2003-01-21 | Avesta Polarit Ab Publ | Method and apparatus for pickling |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2165326A (en) * | 1934-10-30 | 1939-07-11 | Hanson Van Winkle Munning Co | Electrolytic treatment of ferrous metals |
| US3338809A (en) * | 1966-06-23 | 1967-08-29 | United States Steel Corp | Method of cleaning ferrous metal strands electrolytically, including moving said strands in a horizontal plane through an electrolyte while under the influence of alternating electrical fields |
-
1975
- 1975-01-01 AR AR259715A patent/AR204283A1/en active
- 1975-01-21 US US542757*A patent/US3926767A/en not_active Expired - Lifetime
- 1975-06-09 CA CA228,886A patent/CA1046455A/en not_active Expired
- 1975-06-30 IN IN1289/CAL/1975A patent/IN142422B/en unknown
- 1975-06-30 ZA ZA00754166A patent/ZA754166B/en unknown
- 1975-07-02 AU AU82672/75A patent/AU497402B2/en not_active Expired
- 1975-07-07 GB GB2857675A patent/GB1455989A/en not_active Expired
- 1975-07-11 PH PH17376A patent/PH12125A/en unknown
- 1975-07-15 SE SE7508098A patent/SE413039B/en not_active IP Right Cessation
- 1975-07-15 NL NLAANVRAGE7508448,A patent/NL182329C/en not_active IP Right Cessation
- 1975-07-17 TR TR18385A patent/TR18385A/en unknown
- 1975-07-18 RO RO7582890A patent/RO68080A/en unknown
- 1975-07-18 BE BE158454A patent/BE831547A/en not_active IP Right Cessation
- 1975-07-18 BG BG7500030579A patent/BG25382A3/en unknown
- 1975-07-18 IT IT68894/75A patent/IT1041317B/en active
- 1975-07-23 YU YU1868/75A patent/YU39946B/en unknown
- 1975-07-23 BR BR7504688*A patent/BR7504688A/en unknown
- 1975-07-24 ES ES439706A patent/ES439706A1/en not_active Expired
- 1975-07-24 FR FR7523212A patent/FR2298620A1/en active Granted
- 1975-07-25 DE DE19752533319 patent/DE2533319A1/en active Granted
- 1975-07-28 CS CS755293A patent/CS187485B2/en unknown
- 1975-07-29 PL PL1975182374A patent/PL105800B1/en unknown
- 1975-07-29 HU HU75UE69A patent/HU175188B/en unknown
- 1975-07-30 SU SU752162220A patent/SU609480A3/en active
- 1975-07-31 JP JP50093646A patent/JPS5839920B2/en not_active Expired
-
1976
- 1976-01-19 AR AR261963A patent/AR210481A1/en active
Also Published As
| Publication number | Publication date |
|---|---|
| AR204283A1 (en) | 1975-12-10 |
| AU8267275A (en) | 1977-01-06 |
| JPS5839920B2 (en) | 1983-09-02 |
| FR2298620B1 (en) | 1978-10-13 |
| HU175188B (en) | 1980-05-28 |
| SE7508098L (en) | 1976-07-22 |
| ZA754166B (en) | 1976-05-26 |
| DE2533319C2 (en) | 1987-11-05 |
| IN142422B (en) | 1977-07-02 |
| ES439706A1 (en) | 1977-03-01 |
| GB1455989A (en) | 1976-11-17 |
| SE413039B (en) | 1980-03-31 |
| NL182329C (en) | 1988-02-16 |
| CS187485B2 (en) | 1979-01-31 |
| PH12125A (en) | 1978-11-07 |
| FR2298620A1 (en) | 1976-08-20 |
| PL105800B1 (en) | 1979-11-30 |
| US3926767A (en) | 1975-12-16 |
| DE2533319A1 (en) | 1976-07-22 |
| TR18385A (en) | 1977-01-12 |
| AU497402B2 (en) | 1978-12-14 |
| AR210481A1 (en) | 1977-08-15 |
| JPS5183833A (en) | 1976-07-22 |
| BG25382A3 (en) | 1978-09-15 |
| SU609480A3 (en) | 1978-05-30 |
| BR7504688A (en) | 1976-08-17 |
| YU186875A (en) | 1982-02-28 |
| YU39946B (en) | 1985-06-30 |
| NL182329B (en) | 1987-09-16 |
| RO68080A (en) | 1982-05-10 |
| BE831547A (en) | 1976-01-19 |
| NL7508448A (en) | 1976-07-23 |
| IT1041317B (en) | 1980-01-10 |
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