EP1403603A1 - Connecting element for cooling element of a shaft furnace - Google Patents

Abstract

Connecting line is a flexible piece (9) arranged between the mouth region (6) of a coolant channel (5) and a pipe system on one side of a shaft furnace wall (8) and extends through a passage (11) in the oven wall. An Independent claim is also included for a cooling element for a shaft furnace.

Description

The invention relates to a connection line for a cooling element for a shaft furnace, in particular for a blast furnace, which has at least one channel arranged in its interior, through which a coolant flows, the connection line connecting the connection piece between the mouth region of the coolant channel assigned to it and a pipe system is beyond the shaft furnace wall and extends through an opening in the shaft furnace wall. The invention also relates to a cooling element.

Cooling elements, for example the so-called staves, are used to protect the wall of shaft furnaces or the furnace shell in blast furnaces against the temperatures prevailing inside the furnace, to which coolant, usually water, is applied. As a connecting piece between the respective cooling channel and the pipe system, which is usually connected to a treatment system for the coolant, rigid cooling pipe connections are welded in conventional staves to corresponding pipe sockets at the mouth area, ie at the entry or exit area of the coolant channel. The expansion of the cooling elements can lead to thermal expansion. Since the rigid connection lines or supply and discharge pipes are fixed via direct or indirect, ie unintentional fixed points on the tank, these thermal stresses can cause stress cracks, especially in the connection points between the cooling element and pipes, which are responsible for leaks.

To prevent these defects, compensators are installed between the blast furnace and the connection pipes welded firmly in the stave. This ensures a limited relative movement between the blast furnace and the cooling element. Such compensators are known for example from DE 296 08 464 U1.

In certain conditions given by the furnace operation, however, the freedom of movement achieved due to the expansion joints is not sufficient. In addition, the freedom of movement of the connecting pipes is increasingly restricted by other criteria that cannot be directly influenced, such as clogging of the expansion joints due to deposits from the inside of the furnace.

The invention has for its object to provide a solution for a connecting line of a cooling element, in particular a stave, which ensures the greatest possible avoidance of constraint points between the connecting line or the coolant-promoting components and the blast furnace shell. The costs for implementation should not significantly exceed the previous framework for the known connecting lines or pipes.

This object is achieved by means of a connecting line with the features of claim 1 and by means of a cooling element with the features of claim 9. Advantageous further developments are contained in the subclaims.

The main idea of the invention is to design the connection piece or the connection line between the cooling duct and the coolant treatment system not as a rigid pipe connection but as a flexible line piece.

This piece of line is flexible in terms of its shape and type and remains flexible even during use in the installed state.

In this way, fixed points of any kind of the connection line to the furnace are completely avoided. Since only the connecting lines, i.e. the supply and discharge pipes are replaced by a flexible pipe section, there is no change in the heat dissipation performance of the cooling element.

Since the compensator as a component of the known solution with rigid connecting pipes is eliminated and a rigid pipe is replaced by a flexible pipe section, there is an overall cost reduction by reducing the number of necessary components.

In addition, the flexible pipe section can be installed easily.

The flexible line piece consists in particular of a heat-resistant metallic material, for example of a heat-resistant stainless steel. In particular, the line piece is a metallic corrugated hose, for example with a spiral corrugation. This combines the properties of flexibility and elasticity with heat resistance.

The flexible line piece is preferably embedded in an elastic mass. With flexible storage, this ensures a seal against accidental deposits of furnace dust or abrasion of backfill materials on the pipe section.

A gas-tight seal of the part of the flexible pipe section, which is located on the other side, ie outside, of the shaft furnace wall, subsequently specified as a blast furnace shell, is achieved by means of a hood. It is welded gas-tight to the outside of the furnace.

The part of the flexible pipe section which extends between the (cold) outside of the cooling element and the inside of the blast furnace shell is surrounded by a protective tube for the purpose of protection against mechanical damage.

The annular space that then arises between the flexible line piece and the protective tube, the breakthrough in the blast furnace shell and the hood is filled with the elastic sealing compound or packing, which elastically supports and surrounds the flexible line piece during use.

For a quick and tight connection in the mouth areas of the coolant channel, a tube piece in the sense of a coupling element is arranged at the inner end of the flexible line piece. This is shaped in such a way that it can be inserted precisely into the mouth area of the coolant channel. The pipe section is then welded from the outside to the rear of the cooling element. The connection can also be achieved by a flange or screw connection with a corresponding thread or by a plug connection. The coupling element can be formed from the corrugated hose itself or attached to it at the end.

At the other end of the flexible pipe section, which lies beyond the blast furnace shell, a pipe section is also arranged. This is used to connect to the pipes of the blast furnace pipe system. Due to the inner and outer pipe section of the flexible pipe section, quick and easy installation is possible.

The flexible pipe section can be mounted on the cooling element far from the construction site in workshops or on the blast furnace itself. In the first case, cooling elements already equipped with connecting lines according to the invention are then made available on the blast furnace. It is also possible, if necessary already to convert assembled cooling elements with originally rigid connecting lines with the proposed flexible lines.

Fig. 1

eine Schnittansicht eines Teils des Kühlelementes mit einer Anschlussleitung aus einem flexiblen Leitungsstück nach der Erfindung;

Fig. 2

eine Schnittansicht eines Teils des Kühlelementes mit einer Anschlussleitung aus einem starren Rohr nach dem Stand der Technik.

Further details and advantages of the invention emerge from the subclaims and from the following description, in which the embodiment of the invention illustrated in the figure is explained in more detail. Show it:

Fig. 1

a sectional view of part of the cooling element with a connecting line from a flexible line piece according to the invention;

Fig. 2

a sectional view of part of the cooling element with a connecting line from a rigid tube according to the prior art.

1 schematically shows the upper part of a cooling element 1. This cooling element can have been produced from a cast or a rolled or forged base body 2. These are, for example, GGG staves with cast-in cooling tubes or staves with milled channels, which are closed with covers welded on the back. They can also be stavelets.

An embodiment with cooling channels as blind bores is described below by way of example, the invention - as stated - not being restricted to this.

According to FIG. 1, vertical blind holes 3 are drilled into the base body of the cooling element by deep drilling, which merge into horizontal blind holes 4, the vertical and the two horizontal blind holes forming the cooling channel 5. For example, a plurality of these cooling channels 5 can be arranged next to one another in a Cu stave. The horizontal blind bores 4 are not closed at the edges like the vertical blind bores 3, but instead form mouth regions 6 to the outside 7 des Staves. If one speaks in this context of vertical blind bores, then these should run parallel to the longitudinal extension of the stave in the not yet installed state. As can also be seen from the figures, the staves are installed along the shaft furnace wall 8, hereinafter referred to as the blast furnace shell. The course of the cooling channels 5 then corresponds to the orientation of the furnace.

Such staves are flowed through with coolant, usually water, which is transported in and out of a pipe system (not shown) arranged outside the blast furnace.

Between the mouth areas 6 of the cooling channel, ie the exit or entry areas of the cooling channel 5, and such a pipe system beyond the blast furnace shell, a flexible line piece 9, here in the form of a flexible corrugated hose 10 made of steel, is arranged as a connecting piece. The corrugated hose 10 is mounted flexibly and extends through the opening 11 or the opening in the blast furnace shell without further contact points. For locking purposes, the corrugated hose 10 has a pipe socket 12, 13 at the end as a coupling element. With the help of the inner pipe socket 12, the corrugated hose 10 is inserted and welded in the mouth region 6 of the cooling channel 5. The outer pipe socket 13 is a connecting element to the pipe system (not shown) for cooling water treatment. At the same time, the outer pipe socket 13 serves as a connecting element between the corrugated hose 10 and a sealing hood 14, which is welded to the outside 16 of the blast furnace shell with its other end 15 and takes over the gas-tight seal to the blast furnace shell. A protective tube 18 or a sleeve is arranged between the stave and the inside 17 of the furnace. The corrugated hose 10 itself is embedded over its entire length in an elastic sealing compound 19, which keeps the hose 10 tight and free of deposits and, above all, does not influence its flexibility. Due to the flexible or elastic corrugated hose 10 and The elastic sealant 19 between the corrugated hose and the annular space of the opening 11 of the blast furnace shell ensures that there are no fixed points in the connector. Danger points for possible leaks are prevented.

In contrast to this, according to the previously known solution, the connecting line is designed as a rigid connecting pipe 20, as can be seen from FIG. 2. In FIG. 2, components corresponding to FIG. 1 are provided with the same reference symbols. The connecting pipe is rigidly welded in the mouth area 6 of the cooling channel 5 or on a pipe socket of the stave. By means of a compensator 21, the pipe is connected and sealed only indirectly to the blast furnace. A tube 22 serves as mechanical protection.

According to the invention, this fixed piping is replaced by a flexible line piece, in particular a corrugated hose. Fixed points are avoided and thus the build-up of critical stresses during thermal expansion of the cooling element or the resulting leakages. Installation is also quick and easy.

LIST OF REFERENCE NUMBERS

1

cooling element

2

Basic body of the cooling element

3

vertical blind bore

4

horizontal blind bore

5

cooling channel

6

Mouth area of the cooling channel

7

Outside of the cooling element

8th

Shaft furnace wall

9

flexible pipe section

10

Corrugated hose as a flexible pipe section

11

Breakthrough in the shaft furnace wall

12

inner pipe socket

13

outer pipe socket

14

sealing boot

15

one end of the sealing hood

16

(colder) outside of the shaft furnace wall

17

(warmer) inside of the shaft furnace wall

18

thermowell

19

elastic sealant

20

rigid connection pipe

21

compensator

22

pipe

Claims (9)

Connection line for a cooling element (1) for a shaft furnace, which has at least one channel (5) arranged in its interior, through which a coolant flows, the connection line connecting the connecting piece between the mouth region (6) of the coolant channel (5) assigned to it. and a pipe system is beyond the shaft furnace wall (8) and extends through an opening (11) in the shaft furnace wall (8),
characterized,
that the connecting line is a flexible line piece (9). Connection line according to claim 1,
characterized,
that the flexible line piece (9) is a metallic corrugated hose (10). Connection line according to claim 1 or 2,
characterized,
that the flexible line piece (9) is embedded in an elastic mass (19) at least in the area of the opening (11), preferably over its entire length. Connection line according to one of claims 1 to 3,
characterized,
that the part of the flexible pipe section (9), which is located beyond the shaft furnace wall (8), is sealed by means of a gas-tight hood (14) which, surrounding the flexible pipe section (9), is both connected to it and on the shaft furnace wall ( 16) is attached. Connection line according to one of claims 1 to 4,
characterized,
that the part of the flexible line piece (9) which is located on this side of the shaft furnace wall (8) is surrounded by a protective tube (18) or a sleeve for the purpose of protection against mechanical damage. Connection line according to one of claims 3 to 5,
characterized,
that the annular space between the flexible line piece (9) and the protective tube (18), the opening (11) in the shaft furnace wall (8) and the hood (14) is filled with the elastic sealing compound (19). Connection line according to one of claims 1 to 6,
characterized,
that the inner end of the flexible line piece (9) is extended with a pipe socket (12) which can be inserted into the mouth region (6) of the coolant channel (5) and fastened there. Connection line according to one of claims 1 to 7,
characterized,
that the outer end of the flexible line piece (9) with another Pipe socket (13) is extended as a coupling element with the pipe system. Cooling element (1) for a shaft furnace, which has at least one internally arranged channel (5) through which a coolant flows, with a flexible line piece (9) as a connecting line according to one of claims 1 to 8 for connecting the coolant channel with a pipe system.

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