WO2022184190A1

WO2022184190A1 - Device for cooling of metallurgical equipment and method of its production

Info

Publication number: WO2022184190A1
Application number: PCT/CZ2022/000010
Authority: WO
Inventors: Petr SEKO
Original assignee: Inteco Pti S.R.O.
Priority date: 2021-03-05
Filing date: 2022-03-02
Publication date: 2022-09-09
Also published as: EP4302038A1; CZ2021100A3

Abstract

A device for cooling metallurgical equipment comprising a supporting part (1) to which at least one U-shaped cooling channel (2) is connected, wherein the device further comprises at least one L-shaped cooling channel (3), wherein all cooling channels (2,3) are connected to each other by a leak-proof weld (7) and all the outermost channels (2) and/or channel (3) are connected to the supporting part (1) by the leak-proof weld (7), wherein the device further comprises a cooling water inlet (4) and a cooling water outlet (5) at the opposite end of the device, wherein passages (8, 9) are formed in the individual channels (2, 3) to allow cooling water to flow through the channels (2, 3). The method of manufacture comprises welding of the pre-prepared channels (2, 3) provided with the passages (8,9) onto the base supporting part (1), where first the U-shaped cooling channel (2) is joined to the supporting part (1), wherein the procedure for adding the channels (2, 3) depends on the type of equipment, where either the U-shaped channel (2) is first added from the centre of the supporting part (1) by means of welds (6) and then one proceeds to the left-hand and right-hand side with the addition of the channels (3), the channels (2, 3) are joined to each other by the welds (7) and the outermost channel of the device is fixed to the supporting part by the welds (7), or the channel (2) is connected to the supporting part (1) at the edge of the supporting part (1) by means of the weld (7) and at least one channel (3) is successively attached to the side wall of the channel (2) to the supporting part by means of a weld (6), wherein the channels (2,3) are connected to each other by welds (7) and the outermost channel of the device is fixed to the supporting part by the weld (7 ).

Description

Device for cooling of metallurgical equipment and method of its production.

Technical field

The invention relates to a device for cooling metallurgical equipment for use in the metallurgical industry, which solves many of the problems of the prior art, in particular by using the principle of water flow by systematically excluding some parts of the partitions, which multiplies the amount of flowing water in relation to the cross-sectional area of the channel. The invention also relates to a method of manufacture of the device.

Background Art

Equipment that comes into contact with radiant heat sources in the metallurgical industry is known. Heat sources may include an electric arc, hot electrodes, or the liquid steel bath itself. The basic parts that are in contact with the thermal radiation and use various methods of water cooling are also described.

Tube panels

The most commonly used method of manufacturing these parts is from thick-walled tubes placed side by side and connected at the ends by a special fitting. This is a known condition, and the whole system must form a cooling loop.

The main advantage is the cheap and relatively simple manufacture. The disadvantage is the limited range of available tubes and overheating of the water in the case of longer circuits. Nevertheless, the biggest disadvantage is the limited possibility of manufacturing more complex or strictly defined shapes. Castings

Another method of manufacture consists in the casting of parts from pure electro-copper intended for electrical purposes. Again, this is a known manufacturing method.

Once production is established, this method is not overly expensive. However, it is very demanding in terms of copper purity and foundry capacity. Some castings weigh as much as 1000 kg.

Another problem can occur during the manufacture of the cooling circuit, when the wall can melt, or the core of the mould can burn in, and the copper can leak. The whole product is then destroyed.

Machining and welding

Recently, production has been performed in a very demanding and expensive way. Grooves are milled into a rolled copper or steel plate of great thickness, which finally form a cooling loop.

The entire metal wall on which the milling is carried out is subsequently sealed with either copper or steel sheet. The metal sheet is complicatedly welded in various places to prevent water from leaking out of the grooves between the sheet metal and the copper plate. These plates are then joined together into units, interconnected by fittings, to obtain the required flow of cooling water. The disadvantage of this method of manufacture consists in its price, which is up to 2 times higher than the price of conventional casting. Although the part ensures direct contact of the cooling water with the main material, the service life is not significantly greater considering the cost and complexity. Partition system

A system of cooling channels welded from sheets of metal. For the cooled part, a cooling loop is assembled and welded from sheets of metal. While it has a high cooling effect, this is at the expense of a very lengthy welding process. The main advantage is the ease of repair even without special equipment in case of damage.

Summary of the Invention

1. A new method of flow of cooling water which achieves twice the flow rate when using the design of the device according to the present invention. The principle can be clearly seen in Figures 1 and 2.

2. A new method of manufacture of the device. The principle can be seen in Figure 3.

The invention described below overcomes the present disadvantages in the manufacture of the described devices, which are in particular:

• The necessity to use large copper smelting plants and complex technological processes;

• Complicated and expensive machining;

• Complicated or tedious welding;

• High consumption of costly materials such as copper;

• Poor heat transfer between the cooled wall and the cooling liquid.

The invention presented herein describes a device and method of making the same, comprising the features and providing the advantages described below: • The device consists in the formation of a system of channels made of bent sheets where the flow of cooling water is ensured by systematically removing some of the partitions. Due to this principle, the water flow is twice as high in relation to the cross-sectional area of the channel.

• Manufacture of all the parts that make up the device is possible using basic equipment found in conventional machinery workshops.

• Most of the parts are made of sheet metal, which is a readily available, easily formed, and easily workable material.

• Variability in the use of different material thicknesses depending on thermal or mechanical stress.

• This method provides the option of using different sheet metal materials, such as steel, stainless steel, or copper in particular.

• The channel system of the device ensures sufficient robustness for equipment in the metallurgical industry.

• The major advantage is the fact that the cooled wall is of uniform thickness and is completely flooded with cooling medium. Therefore, the heat is transferred evenly to the cooling liquid and for this reason use of a material with high thermal conductivity such as copper is not necessary.

• The manufacturing method eliminates most of the disadvantages of the existing method of manufacture of cooled equipment in the metallurgical industry.

• Compared to the partition system, the number of welds is reduced due to the bent channel semi-finished parts and the rest of the composition of the entire cooler structure.

• Due to the doubling in water flow, the entire cooled circuit can be made larger or connected in series with another circuit without overheating the cooling medium.

Description of the device The device is described with reference to figures which are examples of device designs and used for illustration purposes.

Fig. 1 shows a cross-section with the sequence of welded channels.

In Fig. 2, a section through the channels is shown, showing the principle of water flow through the cooling labyrinth. The main advantage is the compactness of the solution. The cooling medium, after being fed through the pipe _4 into the channel 2, is dispensed in both directions, and after passing into the next channel 3, it will be brought together at the common opening, and so the whole cycle is repeated up to the outlet _5.

The passages between the channels have in theory the same cross- section as the inlet pipe. In any case, it is advisable to perform a computer simulation of the flow to tune the cooling liquid flow.

The basic principle of device manufacture:

The principle of manufacture is shown in Fig. 3. It consists in successive welding of pre-prepared bent channels 2, 3 onto the basic supporting part 1 made of sheet metal. The process of adding channels depends on the type of product, where sometimes it may start from the centre and proceed to the left-hand side and to the right-hand side, and other times it is welded from one side to the other. The pre-prepared channels must be welded in a precisely sequenced order to ensure proper cooling medium flow and to ensure that all welds can be carried out.

Details of the manufacturing method of the device

Design The whole structure consists of two basic parts and an inlet and outlet. All parts are relatively easy to manufacture from sheet metal. The basic part called the supporting part 1,made of thicker sheet metal, serves as the base for the whole equipment and is also in contact with the heat source. The second part of the equipment are channels made of thinner sheet metal. A press brake is used for the manufacture of both parts, with which a relatively high bending accuracy is ensured.

The supporting part

The supporting part respectively the supporting metal sheet is produced by laser cutting, plasma cutting or any other basic cutting technology. It is good to produce as many details as possible using this technology. After cutting, bending is performed on a press brake. In some cases, it is necessary to use chip machining operations to complete all the necessary details. After the completion of each operation, it is important to perform check measurements of the basic and important dimensions. Once these operations are completed, the supporting part is ready for the welding of the channels, water inlet and outlet and other parts if necessary. Its shape corresponds largely to the shape of the final product. It can be a simple plate or a u-shape or an open box. In Fig. 5 and 6 there are examples of supporting parts. These parts form a part of the side passage for the burner. The picture always shows the final shape and the shape before bending. Fig. 5 shows the basic part of the casing and Fig. 6 shows the basic part of the bottom.

Channels

The L profile is the basis of each channel. Depending on the location, it can have one or both faces closed. At least one channel in the equipment is always U-shaped. The basic shape is again produced using the conventional method of basic cutting. The thickness of the sheet metal is always less than the thickness of the basic part. After bending and checking the dimensions, it is necessary to make the passages to connect the channels. Each channel includes adjustments for welds. The number of channels depends on the size and shape of the equipment. The picture is only illustrative to explain the principle of cooling. The minimum number of channels is two, whereas an even number is optimal. The maximum number of channels is not limited but depends on the outlet water temperature to avoid overheating or steam formation. Figures 7 and 8 show examples of channel shapes. These are channels in the bottom weldment for lateral passage into the furnace. Fig. 7 shows a U-shaped channel with an opening for the cooling liquid inlet. Fig. 8 shows an L-shaped channel with an opening in the partition.

Welding

As already stated, welding is carried out sequentially in a precise order. The basic channel 2_ is welded to the supporting part 1 and then the other channels 3 are welded to create a cooling circuit. Leak-proof as well as untight welds are performed by welding. All this can be seen in Figure 2. The welds 6 between channels 2, 3 and the base supporting part 1 do not have to be leak-proof, they only serve to increase the stiffness of the whole equipment and to separate the channels. Welds 7 on the perimeter and inner surface of the cooled device must be made leak-proof. When welding, it is desirable to carry out periodic dimensional and deformation checks. In case the permitted tolerances are exceeded, measures must be taken to ensure that the necessary accuracy is maintained. Once all welds on the cooling circuit have been completed, a pressure leak test must be carried out. After a successful test, the entire equipment is fully completed. ANALYSES

When any new equipment is designed, it is advisable to perform a computer simulation of the flow and heat transfer.

List of figures

Fig. 1. shows a cross section of the device with the sequence of the channels to be welded. It also shows the inlet and outlet of cooling water and heat access.

Fig. 2 shows a section through the channels with an explanation of the principle of water flow through the cooling labyrinth.

Fig. 3 shows a side section through the equipment, with the supporting part and channels marked, showing a schematic view of the design of welds of the device.

Fig. 4 shows an example of the use of a device according to the invention for a bottom part that forms part of a furnace burner side inlet assembly.

Fig. 5 shows an example of the embodiment of the invention for a supporting part which forms part of a side passage for a burner. Fig. 6 shows an example of the embodiment of the invention for a supporting part which forms part of a side passage for a burner. Fig. 7 shows an example of the embodiment of the invention for a U-shaped channel with an opening for cooling liquid inlet.

Fig. 8 shows an example of the embodiment of the invention for an L-shaped channel with an opening in the partition.

Examples of the Embodiments

Example 1

A device for cooling metallurgical equipment, comprising a supporting part 1 to which a U-shaped cooling channel 2 is connected by a leak-proof weld 1_, wherein the device further comprises three L-shaped cooling channels 3 which are connected to adjacent channels 2, _3 by welds 2 and are connected to the supporting part 1 by a weld §_, wherein the device further includes a cooling water inlet and a cooling water outlet 5 at the opposite end of the device, wherein passages 2' 2 ^are formed in each of the channels , 3 to allow cooling water to flow through the channels 2, 3.

Example 2

A device according to example 1, with the difference being that the outermost cooling channels 2, 3 are always connected to the supporting part 1 by a leak-proof weld 1_. The supporting part A is made of a sheet of greater thickness than the sheet from which the cooling channels 2,3 are formed. The channel 2 which contains the cooling water inlet _4 has just two passages 2 formed with the adjacent channel 3 which are situated at the edges of these channels 2, 3, while this adjacent channel 3 has a common passage 9 formed with another channel 3 immediately adjoining it approximately in the middle of the channels 3 at the level of the axis of the cooling water inlet 4_ and outlet 5. This common passage 9 occupies approximately the same cross-sectional area as the two passages Q_ in the channels 2, 3 together, which have passages 8_ formed at the edges of the channels 2, 3. The cooling channels 2 3 are provided with a treatment for welds 6_or welds 1_.

Example 3

A device according to Example 1, with the difference being that the size of the cross-sectional area of the passage 9 corresponds to the size of the cross-sectional area of the inlet _4 of the cooling liquid and the size of the cross-sectional area of the outlet 5 of the cooling liquid.

Example 4 The device in Figure 4 shows the use of the invention for a bottom part that forms part of a side burner inlet assembly for a furnace. Here, cooling water passes through a channel 3 after the inlet , then continues around the perimeter of the burner opening 1_2 through the right channel 11_ and left channel 10 and channel assembly 2_. It then flows out through the labyrinth of channels 3 via the outlet _5.

Example 5

Another application of the invention is cooled penetrations in the EBT space of the furnace for burners or other equipment. Basically, it is a box without a lid with an opening in the middle. The bottom of the box exposed to the heat radiation from the furnace is then cooled by the channel system described above.

Example 6

A method of manufacturing a device according to any of the preceding examples comprising the gradual welding of pre-prepared channels 2, 3 provided with passages 8_, 9 onto a base supporting part 1, wherein a U-shaped cooling channel 2 is first joined to the supporting part 1, the procedure for adding the channels 2, 3 depending on the type of equipment, where the U-shaped channel 2 is first added from the centre of the supporting part 1 by means of welds 6 and one then proceeds to the left-hand and right-hand side with the addition of channels 3, wherein the channels 2, 3 are connected to each other by welds 1_ and the outermost channel of the device is attached to the supporting part by a weld 1_.

Example 7

A method of manufacturing a device according to the example, except that the channel 2 is connected to the supporting part 1 at the edge of the supporting part 1 by means of the weld 1_ and one or more channels 3 are gradually attached to the side wall of the channel 2 by means of the weld 6> to the supporting part, wherein the channels 2, _3 are connected to each other by welds 1_ and the outermost channel of the device is fixed to the supporting part by the weld 7.

Industrial Utilization

The invention is industrially useful in the metallurgical industry for cooling metallurgical equipment, particularly furnaces.

List of Reference Marks

1 - supporting part

2 - U-shaped cooling channel

3 - L-shaped cooling channel

4 - cooling water inlet

5 - cooling water outlet

6 - weld

7 - leak-proof weld

8 - passage through channels

9 - common passage through channels

10 - left arched channel

11 - right arched channel

12 - opening for burner mounting K1 - first chamber

K2 - second chamber K3 - third chamber K4 - fourth chamber

Claims

1. A device for cooling metallurgical plant, characterized in that it comprises a supporting part (1) to which at least one U-shaped cooling channel (2) is connected, wherein the device further comprises at least one L-shaped cooling channel (3), wherein all cooling channels (2, 3) are connected to each other by a leak- proof weld (7) and all outermost channels (2) and/or channels (3) are connected to the supporting part (1) by the leak-proof weld (7), wherein the device further comprises a cooling water inlet (4) and a cooling water outlet (5) at the opposite end of the device, wherein passages (8, 9) are formed in the individual channels (2, 3) to allow cooling water to flow through the channels (2, 3).

2. A device according to claim 1, characterized in that the supporting part (1) and the cooling channels (2, 3) are formed of sheet metal, wherein the supporting part (1) is formed of sheet metal with a greater thickness than the sheet metal from which the cooling channels (2, 3) are formed.

3. A device according to claim 1, characterized in that the cooling channels (2, 3) are provided with a treatment for welds (6) or welds (7).

4. A device according to any one of claims 1 to 3, characterized in that the channel (2) or the channel (3) comprising the cooling water inlet (4) or the cooling water outlet (5) has just two passages (8) formed with the adjacent channel (2) or the adjacent channel (3), which are situated at the edges of these channels (2, 3), while this adjacent channel (2) or channel (3) has a common passage (9) formed with another channel immediately adjacent to it approximately in the middle of the channel, usually at the level of the axis of the cooling water inlet (4) or the cooling water outlet (5).

5. A device according to claim 4, characterized in that this common passage (9) occupies approximately the same cross-sectional area as the two passages (8) in the channels (2) or channels (3) together, which comprise the passages (8) formed at the edges of these channels (2, 3).

6. A device according to any one of claims 1 to 5, characterized in that it comprises at least one cooling channel (2) with the cooling liquid inlet (4) which is connected to the supporting part (1) by the leak-proof weld (7), wherein at least three cooling channels (3) are connected to the cooling channel (2), which are connected to each other and at least two of which are connected to the supporting part (1) by a weld (6),wherein the outermost cooling channel (3) is connected to the supporting part (1) by the leak- proof weld (7) and contains the cooling liquid outlet (5).

7. A device according to any one of claims 1 to 6, characterized in that the size of the cross-sectional area of the passage (9) corresponds to the size of the cross-sectional area of the cooling fluid inlet (4) and the size of the cross-sectional area of the cooling liquid outlet (5).

8. A method of manufacture of the device according to any one of claims 1 to 7, characterized in that it comprises gradual welding of the pre-prepared channels (2,3) provided with passages (8, 9) onto the base supporting part (1), wherein the U-shaped cooling channel (2) is first connected to the supporting part (1), wherein the procedure for adding the channels (2, 3) depends on the type of product, wherein

- either the U-shaped channel (2) is first added from the centre of the supporting part (1) by means of the welds (6) and then one proceeds to the left-hand and right-hand side with the addition of channels (3) connected to each other by the leak-proof weld (7), the channels (2,3) are connected to each other by the welds (7) and where the outermost channel of the device is attached to the supporting part by the weld (7),

- or the channel (2) is connected to the supporting part (1) at the edge of the supporting part (1) by means of the weld (7) and at least one channel (3) is attached to the side wall of the channel (2) to the supporting part by means of the weld (6), wherein the channels (2, 3) are connected to each other by the welds (7) and where the outermost channel of the device is attached to the supporting part by the weld (7)

9. A method of manufacture of the device according to claim 8, characterized in that the supporting part (1) is machined by a chip machining method before the weld (6) and/or the weld (7) is carried out.

10. A method of manufacture of the device according to claim 8 or 9, characterized in that after the individual weld (6) and/or weld (7) or a group of welds (6, 7) has been carried out, the device is checked for dimensions and deformations.

11. A method of manufacture of the device according to any one of claims 8 to 10, characterized in that upon completion of all the welds (6, 7) a pressure test is performed to test the leak proofness of the device.