EP0084752A1 - Process for chromium plating the inner surface of tubes, anode used in this process - Google Patents

Process for chromium plating the inner surface of tubes, anode used in this process Download PDF

Info

Publication number
EP0084752A1
EP0084752A1 EP82402398A EP82402398A EP0084752A1 EP 0084752 A1 EP0084752 A1 EP 0084752A1 EP 82402398 A EP82402398 A EP 82402398A EP 82402398 A EP82402398 A EP 82402398A EP 0084752 A1 EP0084752 A1 EP 0084752A1
Authority
EP
European Patent Office
Prior art keywords
anode
tubular element
different
wall
chromium
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.)
Granted
Application number
EP82402398A
Other languages
German (de)
French (fr)
Other versions
EP0084752B1 (en
Inventor
Bernard Marliac
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Direction General pour lArmement DGA
Etat Francais
Original Assignee
Direction General pour lArmement DGA
Etat Francais
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Direction General pour lArmement DGA, Etat Francais filed Critical Direction General pour lArmement DGA
Publication of EP0084752A1 publication Critical patent/EP0084752A1/en
Application granted granted Critical
Publication of EP0084752B1 publication Critical patent/EP0084752B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D7/00—Electroplating characterised by the article coated
    • C25D7/04—Tubes; Rings; Hollow bodies

Definitions

  • the invention relates to a process for chroming the interior surface of a tubular element, such as for example a weapon tube, by electrolytic deposition as well as to an anode allowing the implementation of this process.
  • the invention also relates to the tubular elements thus coated.
  • One solution is to make the two thicknesses separately by doing two successive chrome plating.
  • Another solution consists in carrying out the chromium plating of the two parts in the same bath by putting in place a cover which masks the part of the deposit of small thickness after the time necessary for its chromium plating.
  • the first solution is obviously long since it requires two successive chromium plating operations.
  • the second solution is difficult to implement and in any case requires intervention during the electrolytic treatment.
  • the present invention therefore proposes to remedy these drawbacks and to provide a method of chromium plating the internal surface of a tubular element which allows, in a single operation, to chromium plating several zones intended to have deposits of different thicknesses and which simultaneously allows a pro transition aggressive and regular between deposits of different thicknesses.
  • Yet another objective of the invention is to provide such a method which is easy to implement and of an economic cost price while not requiring more time than is necessary to ensure the establishment of the deposit. the thickest.
  • Yet another objective of the invention is to provide anodes which make it possible to implement such a method.
  • the subject of the invention is a method of chromium plating of the interior surface of a tubular element by electrolytic means in which an anode centered on the axis of the element is placed inside the tubular element.
  • tubular and an electrolytic liquid is introduced allowing, during the passage of the electric current, to deposit a deposit of chromium on the tubular wall forming cathode of the tubular element, characterized in that, to achieve, on successive sections of the interior wall of the tubular element, deposits of different thicknesses, the anode is made up of several parts of different conductivities, namely one part per section of tubular element to be coated, the value of the conductivity and the diameter of the corresponding part anode being chosen as a function of the thickness of the deposit to be produced on the corresponding section of the wall of the tubular element.
  • the anode provided may consist of several consecutive strands of different conductivities or, if appropriate, of a central part coated with tubular sleeves of different conductivities.
  • the electrolysis liquid is circulated inside the tube in order to constantly ensure its renewal and its homogenization.
  • the subject of the invention is also, as new industrial products, the anodes used in this process and being characterized in that they comprise at least two successive parts of different conductivities.
  • the subject of the invention is also the tubular elements thus coated, these tubular elements being characterized, on their inner wall, by chromium deposits of different thicknesses, joined together by regularly progressive thicknesses connection zones.
  • a tubular element 1 comprising two sections, namely a fairly elongated section 2, followed by a shorter section 3.
  • the section 2 has a constant diameter over most of its length, then a first conical widening of a slight slope 2a, followed by a cylindrical part 2b.
  • the section 3 has a cylindrical part 3a of large diameter while a conical connection zone 4 joins the cylindrical parts 2b and 3a, the zone 4 belonging half to the section 2 and half to the section 3.
  • a part 10 also acting as a "current thief", this part supporting a centering part 11.
  • a nut 12 On the threaded end of the anode 5, is screwed a nut 12 with a washer 13 on which comes to bear a tubular spacer 14 with the interposition of a number of Belleville washers 15 which, taking support on the other hand on the part 11, serve to put the anode 5 in tension and in the keep strictly in a coaxial position.
  • the anode 5 has, inside the tubular element 1, a first part 5a formed of a brass-lead rod which is followed, in section 3, by a strand 5b of platinum titanium. Outside the tube, the strand 5b is continued by a brass-lead rod 5c. It can be seen that the strands 5a and 5b have different diameters, the diameter of the strand 5a being greater than that of the strand 5b.
  • a usual bath of chromic acid is circulated in the tubular element, around the anode 5, entering via the conduit 16 and leaving it via the conduit 17, means for circulation and regeneration of the bath (not shown) being arranged outside.
  • the length of the transition zone 4 is approximately 10 mm.

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)
  • Electroplating And Plating Baths Therefor (AREA)

Abstract

1. Electrolytic process for depositing different thicknesses of chromium on the inside wall of successive length of a tube element, inside which is placed one anode (5) centered on the tube elements axis (1) and an electrolytic liquid which, when an electric current is passed through it, deposits chromium on the wall of the tube, which is the cathode of the tube element, characterized by the fact that anode (5) is made up of several parts (5a, 5b) having different electric conductivities, with one part (5a, 5b) per length (2, 3) of tube element to be coated, with the conductivity and diameter of corresponding anode part (5a, 5b) being chosen as a function of the thickness of the deposition to be made on the corresponding length of tube element wall (1).

Description

L'invention a trait à un procédé de chromage de la surface intérieure d'un élément tubulaire, tel que par exemple un tube d'arme, par dépôt électrolytique ainsi qu'à une anode permettant la mise en oeuvre de ce procédé. L'invention a également trait aux éléments tubulaires ainsi revêtus.The invention relates to a process for chroming the interior surface of a tubular element, such as for example a weapon tube, by electrolytic deposition as well as to an anode allowing the implementation of this process. The invention also relates to the tubular elements thus coated.

Le problème du chromage intérieur d'un élément tubulaire métallique par voie électrolytique est relativement délicat. En effet, lorsque l'on désire obtenir un dépôt de chrome de forte épaisseur sur une grande longueur, il est difficile d'obtenir un aspect suffisamment lisse et homogène pour permettre un rodage après chromage.The problem of interior chromium plating of a metallic tubular element by electrolytic means is relatively delicate. In fact, when it is desired to obtain a thick chromium deposit over a long length, it is difficult to obtain a sufficiently smooth and homogeneous appearance to allow running in after chromium plating.

Si l'on cherche à obtenir des épaisseurs différentes dans des zones différentes de la longueur de l'élément tubulaire, par exemple un dépôt de forte épaisseur suivi d'un dépôt de faible épaisseur, le problème se complique encore.If one seeks to obtain different thicknesses in different zones of the length of the tubular element, for example a deposit of great thickness followed by a deposit of thinness, the problem becomes even more complicated.

Une solution consiste à réaliser les deux épaisseurs séparément en faisant deux chromages successifs. Une autre solution consiste à effectuer le chromage des deux parties dans le même bain en mettant en place un cache venant masquer la partie du dépôt de faible épaisseur au bout du temps nécessaire à son chromage. La première solution est évidemment longue car elle nécessite deux opérations de chromage successives. La seconde solution est délicate à mettre en oeuvre et demande de toute façon une intervention pendant le traitement électrolytique.One solution is to make the two thicknesses separately by doing two successive chrome plating. Another solution consists in carrying out the chromium plating of the two parts in the same bath by putting in place a cover which masks the part of the deposit of small thickness after the time necessary for its chromium plating. The first solution is obviously long since it requires two successive chromium plating operations. The second solution is difficult to implement and in any case requires intervention during the electrolytic treatment.

Enfin, dans les deux cas, il n'est pas possible d'obtenir une zone de transition régulière satisfaisante entre les deux dépôts d'épaisseurs différentes. En particulier, il existe un risque d'écaillage dû au recouvrement des deux plages de chrome et/ou un passage brutal de la partie de faible épaisseur à la partie de grande épaisseur.Finally, in both cases, it is not possible to obtain a satisfactory regular transition zone between the two deposits of different thicknesses. In particular, there is a risk of chipping due to the overlapping of the two chromium areas and / or a sudden passage from the thin part to the very thick part.

La présente invention se propose donc de remédier à ces inconvénients et de fournir un procédé de chromage de la surface intérieure d'un élément tubulaire qui permette, en une seule opération, d'assurer le chromage de plusieurs zones destinées à avoir des dépôts d'épaisseurs différentes et qui permette simultanément d'obtenir une transition progressive et régulière entre les dépôts d'épaisseurs différentes.The present invention therefore proposes to remedy these drawbacks and to provide a method of chromium plating the internal surface of a tubular element which allows, in a single operation, to chromium plating several zones intended to have deposits of different thicknesses and which simultaneously allows a pro transition aggressive and regular between deposits of different thicknesses.

Un autre objectif encore de l'invention est de fournir un tel procédé qui soit facile à mettre en oeuvre et d'un prix de revient économique tout en ne demandant pas plus de temps qu'il est nécessaire pour assurer la mise en place du dépôt le plus épais.Yet another objective of the invention is to provide such a method which is easy to implement and of an economic cost price while not requiring more time than is necessary to ensure the establishment of the deposit. the thickest.

Un autre objectif encore de l'invention est de fournir des anodes permettant de mettre en oeuvre un tel procédé.Yet another objective of the invention is to provide anodes which make it possible to implement such a method.

L'invention a pour objet un procédé de chromage de la surface intérieure d'un élément tubulaire par voie électrolytique dans lequel on met en place, à l'intérieur de l'élément tubulaire, une anode centrée sur l'axe de l'élément tubulaire et on introduit un liquide électrolytique permettant, lors du passage du courant électrique, de déposer un dépôt de chrome sur la paroi tubulaire formant cathode de l'élément tubulaire, caractérisé en ce que, pour réaliser, sur des tronçons successifs de la paroi intérieure de l'élément tubulaire, des dépôts d'épaisseurs différentes, on constitue l'anode en plusieurs parties de conductibilités différentes, à savoir une partie par tronçon d'élément tubulaire à revêtir, la valeur de la conductibilité et le diamètre de la partie correspondante d'anode étant choisis en fonction de l'épaisseur du dépôt à réaliser sur le tronçon correspondant de la paroi de l'élément tubulaire.The subject of the invention is a method of chromium plating of the interior surface of a tubular element by electrolytic means in which an anode centered on the axis of the element is placed inside the tubular element. tubular and an electrolytic liquid is introduced allowing, during the passage of the electric current, to deposit a deposit of chromium on the tubular wall forming cathode of the tubular element, characterized in that, to achieve, on successive sections of the interior wall of the tubular element, deposits of different thicknesses, the anode is made up of several parts of different conductivities, namely one part per section of tubular element to be coated, the value of the conductivity and the diameter of the corresponding part anode being chosen as a function of the thickness of the deposit to be produced on the corresponding section of the wall of the tubular element.

On constate que, grâce à l'invention, il est possible ainsi non seulement d'obtenir, dans une même phase de dépôt électrolytique, des épaisseurs de dépôt différentes suivant les tronçons de paroi intérieure prévus, mais encore de réaliser entre deux dépôts consécutifs une zone de transition progressive et régulière.It can be seen that, thanks to the invention, it is thus possible not only to obtain, in the same phase of electrolytic deposition, different thicknesses of deposition according to the sections of inner wall provided, but also to achieve between two consecutive deposition a progressive and regular transition zone.

Dans le cas cependant où l'on souhaiterait obtenir des zones de transition progressives et régulières ayant elles- mêmes une grande longueur, on peut avantageusement prévoir, au niveau correspondant de l'anode, plusieurs parties successives relativement courtes de conductibilités différentes,par exemple décroissantes,si l'on veut une diminution régulière de l'épaisseur.However, in the case where it is desired to obtain progressive and regular transition zones which themselves have a long length, it is advantageous to provide, at the corresponding level of the anode, several successive relatively short parts of different conductivity, for example decreasing , if you want a regular decrease in thickness.

De façon avantageuse, l'anode prévue peut être constituée de plusieurs brins consécutifs de conductibilités différentes ou bien, le cas échéant, d'une partie centrale revêtue de manchons tubulaires de conductibilités différentes.Advantageously, the anode provided may consist of several consecutive strands of different conductivities or, if appropriate, of a central part coated with tubular sleeves of different conductivities.

Dans une forme de réalisation préférée, on procède, pendant l'électrolyse, à une circulation du liquide d'électrolyse à l'intérieur du tube afin d'assurer constamment son renouvellement et son homogénéisation. On peut ainsi obtenir, sur de très grandes longueurs, des dépôts extrêmement réguliers et lisses.In a preferred embodiment, during electrolysis, the electrolysis liquid is circulated inside the tube in order to constantly ensure its renewal and its homogenization. One can thus obtain, over very long lengths, extremely regular and smooth deposits.

L'invention a également pour objet, à titre de produits industriels nouveaux, les anodes utilisées dans ce procédé et se caractérisant par le fait qu'elles comportent au moins deux parties successives de conductibilités différentes.The subject of the invention is also, as new industrial products, the anodes used in this process and being characterized in that they comprise at least two successive parts of different conductivities.

L'invention a également pour objet les éléments tubulaires ainsi revêtus , ces éléments tubulaires se caractérisant, sur leur paroi intérieure, par des dépôts de chrome d'épaisseurs différentes, réunis entre eux par des zones de raccordement d'épaisseurs régulièrement progressives.The subject of the invention is also the tubular elements thus coated, these tubular elements being characterized, on their inner wall, by chromium deposits of different thicknesses, joined together by regularly progressive thicknesses connection zones.

D'autres avantages et caractéristiques de l'invention apparaîtront à la lecture de la description suivante faite à titre d'exemple non limitatif et se référant au dessin annexé dans lequel la figure unique représente une vue en coupe transversale d'un élément tubulaire avec son anode.Other advantages and characteristics of the invention will appear on reading the following description given by way of nonlimiting example and referring to the appended drawing in which the single figure represents a cross-sectional view of a tubular element with its anode.

En se référant à la figure, on voit qu'on a représenté un élément tubulaire 1, comprenant deux tronçons, à savoir un tronçon assez allongé 2, suivi d'un tronçon plus court 3. On voit que le tronçon 2 présente un diamètre constant sur la plus grande partie de sa longueur, puis un premier élargissement conique de faible pente 2a, suivi d'une partie cylindrique 2b. Le tronçon 3 possède une partie cylindrique 3a de grand diamètre alors qu'une zone de raccordement conique 4 réunit les parties cylindriques 2b et 3a, la zone 4 appartenant pour moitié au tronçon 2 et pour moitié au tronçon 3.Referring to the figure, it can be seen that a tubular element 1 has been shown, comprising two sections, namely a fairly elongated section 2, followed by a shorter section 3. It can be seen that the section 2 has a constant diameter over most of its length, then a first conical widening of a slight slope 2a, followed by a cylindrical part 2b. The section 3 has a cylindrical part 3a of large diameter while a conical connection zone 4 joins the cylindrical parts 2b and 3a, the zone 4 belonging half to the section 2 and half to the section 3.

On voit qu'à l'intérieur du tube 1 est montée une anode allongée coaxiale 5 traversant une pièce de centrage 6 qui est réunie à un manchon 7, dit "voleur de courant", fixé autour et'en bout du tronçon 2. Une entretoise 8 entourant l'extrémité émergente de l'anode 5 prend appui sur la pièce 6 et se termine par une pièce 9 formant à la fois crochet de suspension et de contact pour l'anode.We see that inside the tube 1 is mounted an elongated coaxial anode 5 passing through a centering piece 6 which is joined to a sleeve 7, called "current thief", fixed around and at the end of the section 2. A spacer 8 surrounding the emerging end of the anode 5 bears on the part 6 and ends in a part 9 forming both a suspension and contact hook for the anode.

A l'autre extrémité du tube, il est prévu une pièce 10 faisant également office de "voleur de courant", cette pièce supportant une pièce de centrage 11. Sur l'extrémité filetée de l'anode 5, est vissé un écrou 12 avec une rondelle 13 sur laquelle vient prendre appui une entretoise tubulaire 14 avec interposition d'un certain nombre de rondelles Belle- ville 15 qui, prenant d'autre part appui sur la pièce 11, servent à mettre l'anode 5 en traction et à la maintenir strictement dans une position coaxiale.At the other end of the tube, there is provided a part 10 also acting as a "current thief", this part supporting a centering part 11. On the threaded end of the anode 5, is screwed a nut 12 with a washer 13 on which comes to bear a tubular spacer 14 with the interposition of a number of Belleville washers 15 which, taking support on the other hand on the part 11, serve to put the anode 5 in tension and in the keep strictly in a coaxial position.

L'anode 5 présente, à l'intérieur de l'élément tubulaire 1, une première partie 5a formée d'une tige de laiton-plomb qui est suivie, dans le tronçon 3, d'un brin 5b en titane platiné. A l'extérieur du tube, le brin 5b se poursuit par une tige de laiton-plomb 5c. On voit que les brins 5a et 5b ont des diamètres différents, le diamètre du brin 5a étant supérieur à celui du brin 5b. Un bain usuel d'acide chromique est mis en circulation dans l'élément tubulaire, autour de l'anode 5, en entrant par le conduit 16 et en-sortant par le conduit 17, des moyens de circulation et de régénération de bain (non représenté) étant disposés à l'extérieur.The anode 5 has, inside the tubular element 1, a first part 5a formed of a brass-lead rod which is followed, in section 3, by a strand 5b of platinum titanium. Outside the tube, the strand 5b is continued by a brass-lead rod 5c. It can be seen that the strands 5a and 5b have different diameters, the diameter of the strand 5a being greater than that of the strand 5b. A usual bath of chromic acid is circulated in the tubular element, around the anode 5, entering via the conduit 16 and leaving it via the conduit 17, means for circulation and regeneration of the bath (not shown) being arranged outside.

On constate que, lorsque l'on procède au dépôt électrolytique de chrome, on obtient, dans le tronçon 2, une couche de chrome lisse épaisse et, dans le tronçon 3, une couche mince de chrome également lisse. La transition s'effectue au niveau de la zone 4 sur une longueur de quelques millimètres.A la coupe, on constate que la zone de transition est tout à fait progressive et régulière.It is noted that, when the electrolytic deposition of chromium is carried out, in section 2, a thick smooth layer of chromium is obtained and, in section 3, a thin layer of chromium also smooth. The transition takes place at zone 4 over a length of a few millimeters. Upon cutting, we can see that the transition zone is completely progressive and regular.

A titre d'exemple, on a effectué un dépôt de chrome sur une pièce tubulaire dans les conditions suivantes :

  • Longueur du tronçon 2 : 1726 mm
  • Longueur du tronçon 3 : 115 mm
  • Diamètre interne du tronçon 2 : 0 23 mm
  • Diamètre interne du tronçon 3 : 0 33 mm
  • Diamètre de la partie 5a : φ 13 à 13,5 mm
  • Diamètre de la partie 5b : 0 8 mm
  • Bain : acide chromique à la concentration de 250 g/1 Intensité électrique : 360 ampères
  • Durée du dépôt : 9-h 30 à 10 h.
For example, chromium was deposited on a tubular part under the following conditions:
  • Section 2 length: 1726 mm
  • Section 3 length: 115 mm
  • Internal diameter of section 2: 0 23 mm
  • Internal diameter of section 3: 0 33 mm
  • Diameter of part 5a: φ 13 to 13.5 mm
  • Diameter of part 5b: 0 8 mm
  • Bath: chromic acid at a concentration of 250 g / 1 Electric intensity: 360 amps
  • Duration of the deposit: 9:30 to 10 a.m.

On a obtenu dans le tronçon 2 un dépôt de chrome ayant une épaisseur de l'ordre de 0,22 mm et dans le tronçon 3 un dépôt d'une épaisseur de 0,008 à 0,01 mm.Was obtained in section 2 a deposit of chromium having a thickness of about 0.22 mm and in section 3 a deposit with a thickness of 0.008 to 0.01 mm.

La longueur de la zone de transition 4 est approximativement de 10 mm.The length of the transition zone 4 is approximately 10 mm.

A titre d'exemple de matériaux différents pouvant constituer des parties d'anode et ayant des conductibilités différentes, on pourra prendre :

  • Laiton recouvert de plomb,
  • Cuivre recouvert de plomb,
  • Acier recouvert de plomb,
  • Fer Armco,
  • Titane platiné.
By way of example of different materials which can constitute parts of anode and having different conductivities, we can take:
  • Lead coated brass,
  • Lead coated copper,
  • Lead coated steel,
  • Iron Armco,
  • Platinum titanium.

Claims (8)

1. Procédé de chromage de la surface intérieure d'un élément tubulaire par voie électrolytique dans lequel on met en place, à l'intérieur de l'élément tubulaire, une anode (5) centrée sur l'axe de l'élément tubulaire (1) et on introduit un liquide électrolytique permettant, lors du passage du courant électrique, de déposer un dépôt de chrome sur la paroi tubulaire formant cathode de l'élément tubulaire, caractérisé en ce que, pour réaliser, sur des tronçons successifs de la paroi intérieure de l'élément tubulaire, des dépôts de chrome d'épaisseurs différentes, on constitue l'anode (5) en plusieurs parties (5a, 5b) de conductibilités différentes, à savoir une partie (5a, 5b) par tronçon (2, 3) d'élément tubulaire à revêtir, la valeur de la conductibilité et le diamètre de la partie correspondante (5a, 5b) d'anode étant choisis en fonction de l'épaisseur du dépôt à réaliser sur le tronçon correspondant de la paroi de l'élément tubulaire (1).1. A method of chromium plating the interior surface of a tubular element by electrolytic means in which an anode (5) centered on the axis of the tubular element is placed inside the tubular element ( 1) and an electrolytic liquid is introduced which makes it possible, during the passage of the electric current, to deposit a deposit of chromium on the tubular wall forming the cathode of the tubular element, characterized in that, to produce, on successive sections of the wall inside the tubular element, chromium deposits of different thicknesses, the anode (5) is made up of several parts (5a, 5b) of different conductivities, namely one part (5a, 5b) per section (2, 3) of tubular element to be coated, the value of the conductivity and the diameter of the corresponding part (5a, 5b) of anode being chosen as a function of the thickness of the deposit to be produced on the corresponding section of the wall of the 'tubular element (1). 2. Procédé selon la revendication 1, caractérisé en ce que, pour obtenir une zone de transition progressive de grande longueur, on utilise une anode comprenant, au niveau de la zone de transition, plusieurs parties successives relativement courtes de conductibilités différentes.2. Method according to claim 1, characterized in that, to obtain a progressive transition zone of great length, an anode is used comprising, at the transition zone, several successive relatively short parts of different conductivities. 3. Procédé selon la revendication 1, caractérisé en ce que l'on fait circuler le bain liquide électrolytique entre l'anode et la paroi intérieure de l'élément tubulaire.3. Method according to claim 1, characterized in that the electrolytic liquid bath is circulated between the anode and the inner wall of the tubular element. 4. Anode pour la mise en oeuvre du procédé selon l'une quelconque des revendications 1 à 3, caractérisée en ce qu'elle comporte au moins deux parties successives (5a, 5b) de conductibilités différentes.4. Anode for implementing the method according to any one of claims 1 to 3, characterized in that it comprises at least two successive parts (5a, 5b) of different conductivities. 5. Anode selon la revendication 4, caractérisée en ce que les différentes parties (5a, 5b) ont des diamètres différents.5. Anode according to claim 4, characterized in that the different parts (5a, 5b) have different diameters. 6. Anode selon l'une quelconque des revendications 4 et 5, caractérisée en ce qu'elle est constituée de plusieurs brins consécutifs de conductibilités différentes.6. Anode according to any one of claims 4 and 5, characterized in that it consists of several consecutive strands of different conductivities. 7. Anode selon l'une quelconque des revendications 4 et 5, caractérisée en ce qu'elle est constituée d'une partie centrale revêtue de manchons tubulaires de conductibilités différentes.7. Anode according to any one of claims 4 and 5, characterized in that it consists of a central part coated with tubular sleeves of different conductivities. 8. Elément tubulaire obtenu par le procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce qu'il présente, sur sa paroi intérieure,des dépôts de chrome lisses d'épaisseurs différentes, réunis entre eux par des zones de raccordement d'épaisseurs régulièrement progressives.8. Tubular element obtained by the method according to any one of claims 1 to 3, characterized in that it has, on its inner wall, smooth chromium deposits of different thicknesses, joined together by connection zones regularly progressive thicknesses.
EP19820402398 1982-01-21 1982-12-30 Process for chromium plating the inner surface of tubes, anode used in this process Expired EP0084752B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8200868 1982-01-21
FR8200868A FR2520009A1 (en) 1982-01-21 1982-01-21 PROCESS OF INTERNAL CHROMING OF A TUBULAR ELEMENT, ANODE FOR ITS IMPLEMENTATION AND CHROME ELEMENT OBTAINED ACCORDING TO THIS PROCESS

Publications (2)

Publication Number Publication Date
EP0084752A1 true EP0084752A1 (en) 1983-08-03
EP0084752B1 EP0084752B1 (en) 1986-03-05

Family

ID=9270180

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19820402398 Expired EP0084752B1 (en) 1982-01-21 1982-12-30 Process for chromium plating the inner surface of tubes, anode used in this process

Country Status (3)

Country Link
EP (1) EP0084752B1 (en)
DE (1) DE3269763D1 (en)
FR (1) FR2520009A1 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0335277A1 (en) * 1988-03-28 1989-10-04 Sifco Industries, Inc. Method and apparatus for selective electroplating
US4931150A (en) * 1988-03-28 1990-06-05 Sifco Industries, Inc. Selective electroplating apparatus and method of using same
EP0653503A1 (en) * 1993-10-15 1995-05-17 Rheinmetall Industrie GmbH Method for making a gun barrel with wear resistant internal coating
DE4419864C2 (en) * 1994-06-07 2001-01-11 Rheinmetall W & M Gmbh Electrode for internal electrolytic coating and / or for electropolishing gun barrels
EP1070772A3 (en) * 1999-07-01 2004-01-14 Sumitomo Special Metals Co., Ltd. Electroplating device, and process for electroplating work using the device
WO2007073339A1 (en) * 2005-12-22 2007-06-28 Abb Technology Ltd. A device and a method for metal plating
CN115976617A (en) * 2022-11-23 2023-04-18 西安空间无线电技术研究所 Silver plating process method for auxiliary anode and aluminum alloy multi-bend waveguide part

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR712505A (en) * 1930-06-14 1931-10-03 Orfevrerie Christofle Method and location of electrolytic deposits of metals
GB712314A (en) * 1951-02-08 1954-07-21 Electro Metal Hardening Co S A Method of and apparatus for a uniform electrolytic internal chromium plating of tubes
US3706651A (en) * 1970-12-30 1972-12-19 Us Navy Apparatus for electroplating a curved surface

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR712505A (en) * 1930-06-14 1931-10-03 Orfevrerie Christofle Method and location of electrolytic deposits of metals
GB712314A (en) * 1951-02-08 1954-07-21 Electro Metal Hardening Co S A Method of and apparatus for a uniform electrolytic internal chromium plating of tubes
US3706651A (en) * 1970-12-30 1972-12-19 Us Navy Apparatus for electroplating a curved surface

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0335277A1 (en) * 1988-03-28 1989-10-04 Sifco Industries, Inc. Method and apparatus for selective electroplating
US4931150A (en) * 1988-03-28 1990-06-05 Sifco Industries, Inc. Selective electroplating apparatus and method of using same
EP0653503A1 (en) * 1993-10-15 1995-05-17 Rheinmetall Industrie GmbH Method for making a gun barrel with wear resistant internal coating
US5476581A (en) * 1993-10-15 1995-12-19 Rheinmetall Gmbh Method of producing a weapon barrel having a wear-resistant inner coating
DE4419864C2 (en) * 1994-06-07 2001-01-11 Rheinmetall W & M Gmbh Electrode for internal electrolytic coating and / or for electropolishing gun barrels
EP1070772A3 (en) * 1999-07-01 2004-01-14 Sumitomo Special Metals Co., Ltd. Electroplating device, and process for electroplating work using the device
US6923898B2 (en) 1999-07-01 2005-08-02 Neomax Co., Ltd. Electroplating device, and process for electroplating work using the device
WO2007073339A1 (en) * 2005-12-22 2007-06-28 Abb Technology Ltd. A device and a method for metal plating
CN101341277B (en) * 2005-12-22 2011-06-01 Abb技术有限公司 A device and a method for metal plating
US8192606B2 (en) 2005-12-22 2012-06-05 Abb Technology Ltd. Device and a method for metal plating
CN115976617A (en) * 2022-11-23 2023-04-18 西安空间无线电技术研究所 Silver plating process method for auxiliary anode and aluminum alloy multi-bend waveguide part

Also Published As

Publication number Publication date
FR2520009B1 (en) 1984-03-23
FR2520009A1 (en) 1983-07-22
EP0084752B1 (en) 1986-03-05
DE3269763D1 (en) 1986-04-10

Similar Documents

Publication Publication Date Title
EP1204787B1 (en) Method for continuous nickel-plating of an aluminium conductor and corresponding device
EP0084752B1 (en) Process for chromium plating the inner surface of tubes, anode used in this process
EP0425354B1 (en) Process and apparatus for electroplating a metallic strip
EP0024220B1 (en) Process for manufacturing a tube composed of a metal and plastics material, and apparatus for carrying out this process
EP2649239B1 (en) Device for diverting a structural cable, such as a guy line, and construction comprising same
EP0797219A1 (en) Coaxial cable manufacturing process
FR2655275A2 (en) IMPROVEMENT IN THE PROCESS OF MANUFACTURING A POROUS TUBE COATED INTERIORLY WITH A SEMI-PERMEABLE MEMBRANE BY ELECTROPHORESIS.
FR2660301A1 (en) DEVICE FOR THE PRODUCTION OF OZONE.
EP1106293B1 (en) Electrode for wire electric discharge machining, and manufacturing method thereof
EP0329611B1 (en) Process for continuously coating a filamentary steel article by immersing the article in a bath of the molten coating metal
CA2630910A1 (en) Automatic welding device of the mig/mag type
CA1054832A (en) Internally cooled roller and method of construction_
FR2693129A1 (en) Electrochemical treatment tool for the inside surface of curved pipes - includes a flexible electrode supported with insulating supports from the walls of the tube and strengthened with metal bracings
EP0403362B1 (en) Current conducting roll
FR2481153A1 (en) Drawing ring and mandrel for variable thickness tube - has stepped drawing ring of min. ID to suit mandrel dia.
CH655265A5 (en) Method for manufacturing a wire electrode for electron discharge machining (spark erosion machining)
WO2024116049A1 (en) Device for electrochemical surface treatment of an inner surface of a tubular element made of electrically conductive material, in particular of a weapon barrel, and system comprising such a device
FR2526719A3 (en) WRITING POINT FOR INK WRITING INSTRUMENT
FR2574095A1 (en) Apparatus for electrochemical treatment, of the electrolyte circulation type.
BE527211A (en)
EP3505657A1 (en) Current conductor rollers
CH638837A5 (en) ELECTROPHORETIC COATING METHOD AND APPARATUS FOR REMOVING EXCESS ELECTROPHORETIC MATERIAL FROM THE INTERIOR SURFACE OF AN ELECTROPHORESIS COATED PART.
FR2754198A1 (en) Method for the weld forging of nuts onto a support component
FR2666004A1 (en) Multiple hook and method for manufacturing it
BE421618A (en)

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19830103

AK Designated contracting states

Designated state(s): CH DE LI

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE LI

REF Corresponds to:

Ref document number: 3269763

Country of ref document: DE

Date of ref document: 19860410

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19890126

Year of fee payment: 7

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 19891016

Year of fee payment: 8

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19900901

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19901231

Ref country code: CH

Effective date: 19901231

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL