GB2063919A

GB2063919A - Process for the manufacture of hollow conductor components by electrolysis

Info

Publication number: GB2063919A
Application number: GB8036534A
Authority: GB
Original assignee: KM Kabelmetal AG
Current assignee: KM Kabelmetal AG
Priority date: 1979-11-23
Filing date: 1980-11-13
Publication date: 1981-06-10
Also published as: GB2063919B; FR2470456A1; IT8025912A0; DE2947248A1; DE2947248C2; FR2470456B1; IT1134224B

Abstract

A piece of tube of the requisite cross-section is produced by electrolysis, this electrolysis being interrupted after a predetermined wall thickness has been reached, flanges having internal diameters equal to or not substantially greater than the external diameter of the piece of tube being passed over the ends of the piece of tube; and electrolysis being thereafter continued until the requisite final wall thickness of the hollow conductor component is reached, a metal-to-metal joint being formed between the flanges and the piece of tube. This process avoids risk of distortion entailed in soldering of the flanges.

Description

SPECIFICATION Process for the manufacture of hollow conductor components The invention relates to a process for the manufacture of hollow conductor components (e.g. of copper) in which a piece of tube of the requisite cross-section is produced by electrolysis.

Hollow conductor components are obtainable by procedures in which a hollow conductor is initially produced either by electroplating or by one or more extrusion or drawing processes, and flanges are fitted to the ends, e.g. by soldering.

The soldering of the flanges entails a risk of distortion of the hollow conductors, however, which may well lead to inferior high-frequency transmission properties. Furthermore, inasmuch as the material may soften where it is heated during the soldering, the relevant mechanical requirements may no longer be met after soldering.

It is an object of the invention to provide a process for the manufacture of a hollow conductor component which makes it possible to produce hollow conductor components which are true as to shape, and which are provided with flanges, in an economical manner.

According to the present invention, we provide a process for the manufacture of a hollow conductor component in which a piece of tube of the requisite cross-section is produced by electrolysis, characterised in that: this electrolysis is interrupted after a predetermined wall thickness has been reached; flanges having internal diameters equal to or not substantially greater than the external diameter of the piece of tube are passed over the ends of the piece of tube; and electrolysis is thereafter continued until the requisite final wall thickness of the hollow conductor component is reached, a metal-tometal joint being formed between the flanges and the piece of tube.In addition to offering those advantages which are directly related to the above-stated object, the process of the invention has the advantage that the aperture of each of the flanges lies exactly concentrically with respect to the piece of tube, and an offset flange, which would adversely affect the transmission properties of the product, is not to be feared. A metal-tometal joint can be produced by the electrolysis which is so strong that the joint fully meets the relevant mechanicai requirements.

According to an optional feature of the invention, the surfaces of the flanges, with the exception of their inner zones which lie immediately around the piece of tube, are provided with a layer which prevents electrolytic deposition.

The invention will be explained in more detail with reference to the accompanying diagrammatic drawing, in which Figures 1 and 2 are views in axial section showing two stages in the formation of a hollow conductor component.

By electrolysis, a thin-walled copper tube 1 having a wall thickness of about 0.7 mm is first deposited on a core 6. After this wall thickness has been reached, the core 6 with the copper tube 1 is removed from the electrolytic bath, and flanges 2 and 3 are passed over the ends of the copper tube 1, as shown in Figure 1. The internal diameters of the flanges 2 and 3 approximately correspond to, i.e. are equal to or not substantially greater than, the external diameter of the copper tube 1. With the exception of their inner zones which lie immediately around the tube 1, the flanges 2 and 3 are coated with a lacquer or wax, which prevents electrolytic deposition. The workpiece prepared in this way is next reintroduced into the electrolytic bath, and electrolysis is continued.During the continued electrolysis, the wall thickness of the copper tube 1 increases, and the flanges 2 and 3 are concurrently "electroplated in". The essential feature here is that a deposition by electroplating or electrolysis takes place at the points marked 4 and 5, as shown in Figure 2.

Any interspace which may remain between the flange 2 or 3 and the piece of tube 1 is advantageously filled with an electrically conductive composition, e.g. a mixture of graphite and epoxide resin.

As shown in Figures 1 and 2, end portions of the piece of tube 1 may protrude from the flanges 2 and 3.

After electroplating, the end faces of the flanges 2 and 3 are machined, if desired.

The process of the invention is remarkably useful for the manufacture of hollow conductor components of any desired cross-section, and of any desired shape as seen from the side.

1. Process for the manufacture of a hollow conductor component in which a piece of tube of the requisite cross-section is produced by electrolysis, characterised in that: this electrolysis is interrupted after a predetermined wall thickness has been reached; flanges having internal diameters equal to or not substantially greater than the external diameter of the piece of tube are passed over the ends of the piece of tube; and electrolysis is thereafter continued until the requisite final wall thickness of the hollow conductor component is reached, a metal-tometal joint being formed between the flanges and the piece of tube.

2. Process according to claim 1, characterised in that the surfaces of the flanges, with the exception of their inner zones which lie immediately around the piece of tube, are provided with a layer which prevents electrolytic deposition.

3. Process according to claim 1 or 2, characterised in that end portions of the piece of tube protrude from the flanges.

4. Process according to claim 1, 2 or 3, characterised in that any interspace remaining between either flange and the piece of tube is

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Process for the manufacture of hollow conductor components The invention relates to a process for the manufacture of hollow conductor components (e.g. of copper) in which a piece of tube of the requisite cross-section is produced by electrolysis. Hollow conductor components are obtainable by procedures in which a hollow conductor is initially produced either by electroplating or by one or more extrusion or drawing processes, and flanges are fitted to the ends, e.g. by soldering. The soldering of the flanges entails a risk of distortion of the hollow conductors, however, which may well lead to inferior high-frequency transmission properties. Furthermore, inasmuch as the material may soften where it is heated during the soldering, the relevant mechanical requirements may no longer be met after soldering. It is an object of the invention to provide a process for the manufacture of a hollow conductor component which makes it possible to produce hollow conductor components which are true as to shape, and which are provided with flanges, in an economical manner. According to the present invention, we provide a process for the manufacture of a hollow conductor component in which a piece of tube of the requisite cross-section is produced by electrolysis, characterised in that: this electrolysis is interrupted after a predetermined wall thickness has been reached; flanges having internal diameters equal to or not substantially greater than the external diameter of the piece of tube are passed over the ends of the piece of tube; and electrolysis is thereafter continued until the requisite final wall thickness of the hollow conductor component is reached, a metal-tometal joint being formed between the flanges and the piece of tube.In addition to offering those advantages which are directly related to the above-stated object, the process of the invention has the advantage that the aperture of each of the flanges lies exactly concentrically with respect to the piece of tube, and an offset flange, which would adversely affect the transmission properties of the product, is not to be feared. A metal-tometal joint can be produced by the electrolysis which is so strong that the joint fully meets the relevant mechanicai requirements. According to an optional feature of the invention, the surfaces of the flanges, with the exception of their inner zones which lie immediately around the piece of tube, are provided with a layer which prevents electrolytic deposition. The invention will be explained in more detail with reference to the accompanying diagrammatic drawing, in which Figures 1 and 2 are views in axial section showing two stages in the formation of a hollow conductor component. By electrolysis, a thin-walled copper tube 1 having a wall thickness of about 0.7 mm is first deposited on a core 6. After this wall thickness has been reached, the core 6 with the copper tube 1 is removed from the electrolytic bath, and flanges 2 and 3 are passed over the ends of the copper tube 1, as shown in Figure 1. The internal diameters of the flanges 2 and 3 approximately correspond to, i.e. are equal to or not substantially greater than, the external diameter of the copper tube 1. With the exception of their inner zones which lie immediately around the tube 1, the flanges 2 and 3 are coated with a lacquer or wax, which prevents electrolytic deposition. The workpiece prepared in this way is next reintroduced into the electrolytic bath, and electrolysis is continued.During the continued electrolysis, the wall thickness of the copper tube 1 increases, and the flanges 2 and 3 are concurrently "electroplated in". The essential feature here is that a deposition by electroplating or electrolysis takes place at the points marked 4 and 5, as shown in Figure 2. Any interspace which may remain between the flange 2 or 3 and the piece of tube 1 is advantageously filled with an electrically conductive composition, e.g. a mixture of graphite and epoxide resin. As shown in Figures 1 and 2, end portions of the piece of tube 1 may protrude from the flanges 2 and 3. After electroplating, the end faces of the flanges 2 and 3 are machined, if desired. The process of the invention is remarkably useful for the manufacture of hollow conductor components of any desired cross-section, and of any desired shape as seen from the side. CLAIMS

4. Process according to claim 1, 2 or 3, characterised in that any interspace remaining between either flange and the piece of tube is filled with an electrically conductive composition.

5. Process according to claim 1, substantially as described with reference to the accompanying drawing.

6. A hollow conductor component obtained by a process according to any preceding claim.