HK1120659B - An electrode and a method for forming an electrode - Google Patents

Description

Electrode and method of forming an electrode

Technical Field

The present invention relates to an electrode and a method of forming an electrode, typically a lead alloy anode.

Background

Previously, electrodes were cast from metal and had to be formed with thicker plates (blades) for rigidity and corrosion resistance requirements, since cast metals such as cast lead generally corroded faster than rolled metal.

Later developments achieved the manufacture of electrodes by casting the head of the electrode and rolling the plate, and then welding the plate to the head.

However, such electrodes are relatively difficult to manufacture.

The present invention seeks to solve this problem.

Disclosure of Invention

According to one embodiment of the present invention, a method of forming an electrode includes:

pouring molten metal into the mold to form an electrode with a head portion and a plate portion; and

the plate portion of the electrode is rolled after the electrode is cast.

The method may include rolling the plate portion to at least two different thicknesses.

The method may further comprise inserting a second metal into the mold prior to pouring the molten metal into the mold.

The second metal may be copper.

In one aspect, the metal is lead or a lead alloy and the method involves forming a lead or lead alloy anode.

The present invention also provides an electrode comprising:

a cast head; and

a rolled plate portion integrally formed with the head portion.

The pole plate portion has at least two different thicknesses.

The electrode may include a second metal cast with the electrode.

The second metal may be copper.

In one embodiment, the electrodes are formed from lead or a lead alloy and are lead or lead alloy anodes.

Drawings

FIG. 1 illustrates an example apparatus for fabricating an electrode according to one aspect.

Figure 2 shows a schematic diagram of an electrode formed using the apparatus shown in figure 1.

Figure 3 shows a schematic view of the electrode after casting but before rolling.

Detailed Description

One embodiment is described with reference to the formation of a lead alloy anode, but it will be appreciated that the method may be used for the formation of other metal or metal alloy electrodes, such as an aluminium cathode, as just an example.

Referring to the drawings, a metal or metal alloy is delivered into a crucible 10.

Depending on the alloy, the crucible is heated to a temperature in the range of, for example, 300 ℃ to 600 ℃ and the alloy is melted.

A second metal, such as a copper rod, for example, is placed in the mold 12. Copper is widely used and is the preferred metal. The length, shape and thickness of the copper hanger bar are determined by the weight and size of the anode to be formed.

Under the action of gravity, the molten lead alloy is transferred from the crucible through the connecting tube 14 to the bottom of the mould 12 and rises up and covers the copper bar.

This helps to remove air bubbles and impurities floating on the material metal since the molten lead alloy is gravity fed from the bottom of the mould.

Once the metal has cooled sufficiently, it is placed in a cooling tank 16, if necessary.

In the event that some alloys do not require cooling, the cooling tank 16 will not be used.

The metal is moved from the die 12 to the cooling tank 16 using an overhead travelling beam and hook arrangement 18.

Thus, the first step of casting the metal or metal alloy in the mold is completed, and the metal is now moved into the mold 20 in the form of a horizontal mold.

After the anode is cast but before it is rolled, it is shaped as shown in figure 3, with the plate 32 having a thickness "a".

The die generally includes a guide roller 22 and a press roller 24 having a flywheel pressure drive 26. As the cast metal passes through the horizontal rolls, the cast metal is rolled and the shape of the cast metal changes.

The electrodes can be rolled and cross-rolled, if desired, to be uniformly spread in the molecule.

The width of the plate 32 after rolling is as shown in fig. 2, having thicknesses "B" and "C" thinner than the thickness "a" in fig. 3.

The thickness of the casting prior to rolling is determined by the desired final thickness, which typically needs to be reduced by about 30% to about 70% depending on the alloy used. In the embodiment shown, this value is up to about 3 mm.

In any event, the platen roller 24 is initially generally in a more open position to allow the portion of the electrode with the copper insert to pass in the direction of the pit 28.

Once the copper portion has passed to the predetermined position, the press rolls begin to close to compress the metal or metal alloy portion behind the copper portion.

In this manner, the copper head bar 30 and the pole plate 32 are integrally formed without the need for welding between the head and the pole plate.

Since the head is not immersed in the solution and thus is not subject to corrosion, the head is generally not rolled at all.

The electrodes are then trimmed for shipment.

It will be appreciated that in the case of a fast erosion rate of the electrode near the liquid level, the electrode may be rolled thicker from the head to about 30mm below the liquid level, while the remainder of the plate may be rolled as desired. This example can be seen in figure 2.

Thus, the electrodes will have three different thicknesses. An example of these different thicknesses is shown in the figures.

In any event, the method is applicable to any metal or metal alloy electrode and provides the rolled metal or metal alloy with the required electrical conductivity and mechanical strength, but with a simpler and less costly manufacturing process than previous designs.

In addition, the method allows existing lead anodes to be recast and rolled to provide an improved structure.

Claims (12)

1. A method of forming an electrode, the method comprising:

pouring molten metal into the mold to form an electrode with a head portion and a plate portion; and

and rolling the pole plate part of the electrode after the electrode is cast.

2. The method of claim 1 including rolling the blade portion to at least two different thicknesses.

3. A method according to claim 1 or 2, comprising inserting the second metal into the mould before pouring the molten metal into the mould.

4. A method according to claim 3 wherein the second metal is copper.

5. The method of claim 1 wherein the metal is lead or a lead alloy.

6. A method according to claim 5, wherein the method involves the formation of a lead or lead alloy anode.

7. An electrode, comprising:

a cast head; and

a rolled plate portion integrally formed with the head portion.

8. The electrode of claim 7, wherein the plate portion has at least two different thicknesses.

9. An electrode according to claim 7 or 8, comprising a second metal cast with the electrode.

10. An electrode according to claim 9, wherein the second metal is copper.

11. An electrode according to claim 7, wherein the electrode is formed from lead or a lead alloy.

12. An electrode according to claim 11, wherein the electrode is a lead or lead alloy anode.