EP2703761B1 - Gas purging element with its corresponding gas supply line - Google Patents

Description

The invention relates to a gas purging device on a metallurgical vessel with its gas supply line according to claim 1-8.

A gas purging element, also called gas purging plug, is used for blowing in gases, if appropriate also gas / solid mixtures, into a melt to be treated, in particular a metallurgical melt. In the case of a gas purging plug with directed porosity, the gaseous treatment fluid is guided along corresponding channels / slots, in the case of gas purging ponds with so-called random porosity along a corresponding irregular pore volume.

The arrangement of a gas purging plug in the bottom or the wall of a metallurgical vessel can be done in different ways. In a typical installation, the gas purging plug is placed in an associated well block. Outside, at the end where the gas is supplied, the dishwasher is secured to the metallurgical vessel with a mechanism. To disassemble or replace the purifier, the mechanism is opened.

According to EP 0 148 337 A1 To this mechanism belongs a ring of refractory material which surrounds the gas supply pipe of the gas purging plug and projects radially beyond the bottom of the gas purging plug.

Such gas purging bricks and associated mounting devices have been proven for decades. A problem, however, is that the disassembly / assembly cost when replacing a gas purging element is high, takes a long time and causes relatively high costs.

In order to avoid a diffusion of the gas into the adjacent refractory material, it is for example from the DE 19948848C1 known to form the gas purging plug with a metal jacket. The sheet extends in particular peripherally and in the bottom area of the purifier. The bottom plate has an opening, which is followed by a gas connection pipe which protrudes freely over the bottom plate. This section is called the "cold end" of a gas purging element, while the end opposite in the axial direction of the gas purging element is referred to as the "hot end". After installation of the gas purging element, this end is operatively in contact with the hot melt to be treated. The gas connection pipe is connected via an internal thread to a gas supply line with a corresponding external thread. Gas is blown into the melt via the gas connection tube, the opening and through the directional and / or non-directional pores of the refractory material. In the DE 4029024A1 a Spülanschlusskupplung is proposed, which is bolted to a ladle. The coupling consists of several parts which are fixed against each other via a clamping lever.

The DE 38 33 502 C2 suggests a gas purging plug that has no metallic bottom plate and no gas connection. This gas purging plug is characterized by a free opening at the cold end. A mounting device secures the gas purging plug in the mounting position and serves at the same time to use a gas connection element to guide the gas from there through the gas purging plug.

The gas purging plug according to DE 38 33 502 C2 is easy to transport and assemble, because it does not have the long gas connection pipe like the one Gas purging plug according to EP 0 148 337 A1 , The known device according to DE 38 33 502 C2 however, hardly seals against gas loss.

The invention has for its object to offer a structurally simple way how the assembly or disassembly of a gas purging plug can be simplified and a loss of gas is minimized.

The invention is based on the following considerations: A sheet-metal gas purging plug has many advantages. He has a high dimensional accuracy, avoids gas loss and is insensitive to transport. The latter applies with restriction regarding the gas connection pipe.

In that regard, an inventive idea is to reduce the length of the gas connection pipe to a minimum, so only provide a short gas connection piece.

One or more further components, such as pipes, adapters or the like, can be connected to this gas connecting piece in order to establish a gas connection between the gas source and the gas purging plug.

In this context, a further concept of the invention is to plug such a component and the gas connection piece into each other, so as to provide connection as a connector.

"Plug connection" means that corresponding sections of adjacent components are only inserted into one another in order to achieve the desired fluidic, loss-free as possible passage of the gas. According to common terminology, the Plug connection one male part and one female part. The concrete geometry is not crucial.

The connector makes it possible to connect adjacent sections (of the gas supply system) in the flow direction of the gas only by plugging together. The plug-in connection alone serves to create a largely gas-tight connection. This can be realized, for example, in that corresponding sections of the plug connection have a corresponding conical / frusto-conical shape and are inserted into one another.

The plug-in connection thus primarily serves the gas-tight connection of adjacent components (for example pipe sections), while an additional securing element mechanically secures / fixes adjacent sections in the plug-in position.

The connector requires no tool, the parts to be connected to the "gas line" are simply plugged into each other. This is fast and also at high ambient temperatures.

In its most general embodiment, the invention relates to a gas purging device on a metallurgical vessel having the features of claim 1.

The gas connection piece at the bottom of the gas purging element can be formed in the manner of an adapter. This adapter is to be distinguished from a gas connection pipe of known type. The adapter can be much shorter and has essentially only the task of providing a connection part for a gas supply line. Although this adapter will inevitably lead to gas, but only over a short distance. The length of the adapter in the direction of the gas flow is according to one embodiment <20 cm, often <15 cm or <10 cm. The adapter connects directly to the bottom of the gas purge element.

The adapter / gas connection piece can run from the base plate inwards into the ceramic part of the gas purging plug or vice versa. In both cases, an associated gas supply line is placed with its second end on or in the gas connection pipe to create a continuous gas connection.

The second end of the gas supply line and the adapter in the bottom region of the gas purging element are to be connected by a plug connection to each other and through a to secure additional securing element against unintentional loosening.

For this purpose, it is provided to make the corresponding end portions of the plug-in elements with corresponding internal and external threads (like a union nut), as shown in the figures.

The said sections of the connection connection (gas connection piece / gas supply line) consist for example of pieces of pipe or pieces of hose whose internal cross-section depends on the amount of gas to be conveyed through the connection to the gas purging plug and then through the gas purging plug.

It is possible to form the gas connection piece or the gas supply line with an anti-penetration barrier against penetrating molten metal. For this purpose, the corresponding section may have a gas channel, which runs at least in sections coiled or zigzag.

The break-through protection is thus arranged in front of or at the cold end of the gas purging element (in the direction of the gas flow). The breakthrough safety device can be designed as a replaceable component with a corresponding section of the gas supply line or the gas connection piece is connected, for example, with a connector of the type mentioned.

As already mentioned, the plug-in connection can be formed so that the nested parts (in particular pipe sections) have corresponding geometries from the group: prisms, cones, truncated cones, spheres, paraboloids.

Concretely, the plug connection can be designed in such a way that the free end of the section which lies farther away from the gas purging plug has the largest cross-sectional area, as is also shown in the following description of the figures.

While the connector allows a quick and secure gas-tight connection of adjacent connection parts, the security element has the task of preventing this connection from loosening again.

In that regard, the securing element can also be designed as a pressure or holding device which presses, for example, the gas supply line in the direction of the gas purging plug and / or holds in the plug position.

Other sections of the gas supply line can be connected analog.

The pressure / holding element may be part of a mounting device which is pivotally mounted on the outside of the metallurgical vessel.

The assembly / disassembly device can be dimensioned so that it freely after installation of the gas purging element via the gas connection piece can be pivoted, wherein the mounting device has an opening or a slot through which the gas connection piece and optionally a gas supply line and a fuse element can be passed.

According to the design of the mounting device, the length of the gas connection element is selected, which is part of the gas purging plug.

Figur 1:

einen Längsschnitt durch den Bodenbereich eines metallurgischen Gefäßes mit einer ersten Ausführungsform eines Gasspülsteins

Figur 2a-d:

Längsschnitte durch den Bodenbereich eines metallurgischen Gefäßes mit einer zweiten Ausführungsform eines Gasspülsteins, wobei die einzelnen Montageschritte getrennt dargestellt sind.

The invention will be explained in more detail below with reference to some embodiments. Show - in a schematic representation -

FIG. 1:

a longitudinal section through the bottom portion of a metallurgical vessel with a first embodiment of a gas purging plug

Figure 2a-d:

Longitudinal sections through the bottom region of a metallurgical vessel with a second embodiment of a gas purging plug, wherein the individual assembly steps are shown separately.

In the figures, the same or equivalent components are shown with the same reference numerals.

The reference numeral 10 describes a frusto-conical gas purging plug with an outer metal jacket 12 and a sheet metal bottom 14, which has a central opening 16.

In the illustrated mounting position, above the opening 16, there is a refractory ceramic body 10k having a porous portion 10p, through which a gas can be transported in the direction of arrow G from the lower, cold end 10n of the gas purging plug 10 to its upper (not shown) hot end 10o.

Compared with the porous portion 10p, a gas connection piece 20 for the gas purging plug 10 extends around the opening 16. The gas connection piece 20 with axial gas channel 26 extends downwards from the opening 16 in the illustrated installation position.

The gas connection piece 20 has a first end 20.1 at a distance to the gas purging element 10 and a second end 20.2 adjacent to the gas purging element 10. The second portion 20.2 is welded to the metal bottom 14 (weld 22).

In the region of the second end 20. 2, the gas connection piece 20 has a cross-sectional change on the inside, the part facing the gas purging plug 10 having a larger cross-section. In this section, a body 24 is loosely arranged. Without gas pressure it rests on a shoulder of the described cross-sectional reduction of the gas channel 26. Under gas pressure, the body 24 lifts off the shoulder and moves toward the gas purging plug 10. A locking pin 28 disposed above the body 24 prevents the body 24 from closing off the opening 16.

At the opposite first end 20.1, the gas channel 26 widens conically downwards and outwards. In this part, a second end 30.2 of a gas supply line 30 is inserted gas-tight. This end 30.2 is designed according to a truncated cone (nozzle-like) and its tapered end is up. The end 20.1 forms the can, the end 30.2 the plug of the connector.

In the mounting position, the gas supply line 30 has a shoulder 33 slightly below the first end 20. 1 of the gas connection piece 20. Against the shoulder 32 abuts an annular inner shoulder 42 of a securing element 40, which is also tubular. The securing element 40 has, in the area above the shoulder 42, an internal thread 42i which is screwed onto a corresponding external thread 20.1a of the likewise externally cylindrical first end 20.1 of the gas connecting piece 20. Below the shoulder 42, the securing element 40 extends tubular down to a radially outwardly extending wheel 44 for locking.

In this embodiment, the connection connection of gas connection piece 20 and gas supply line 30 is formed with axially nested sections 20.1, 30.2, wherein the connector is secured via the securing element 40 against loosening.

On the outer jacket 50 of the associated metallurgical vessel, a mounting device 60 is pivotally mounted via a hinge 62, wherein FIG. 1 shows the mounting position, in which the mounting device engages over the gas connection piece 20 and the second end 30.2 of the gas supply line 30 with an annular element 64. The annular member 64 is fixed relative to the fixed outer shell 50 by means of a handle 66 in the position shown. In this case, the element 64 rests against a sleeve 68, which surrounds the second end 20. 2 of the gas connecting piece 20. The sleeve 68 is part of the refractory lining below the Gasspülelementes 10. The first end 20.1 of the gas connection piece 20 protrudes downwards over the sleeve 68 before.

The assembly is simple because the mounting device 60 can be pivoted to the position described before the gas supply line 30 is fitted and secured to the gas connection piece 20. Before the gas-tight connection of the parts 20,30 of the gas purging plug 10 is securely positioned. The gas connection piece 20 of the connection connection is precisely adjusted, so that the plug-in connection with the gas supply line 30 can be very simple, accurate and fast. The length of the gas supply line 30 is arbitrary. The gas supply line 30 may also consist of several sections, which in turn can be connected by plug connection (or otherwise) gas-tight with each other.

• der Gasanschlussstutzen 20 ist nach Art eines Adapters gebildet, der am Metall-Boden 14 des Gasspülsteins 10 befestigt (hier: angeschweißt ist). Der Adapter steht nur 10 mm nach unten über den Boden 14 vor und ist an diesem Ende (20.1) ähnlich wie das erste Ende 20.1 des Gasanschlussstutzens 20 gemäß Figur 1 gestaltet. Analog gilt dies für das zweite Ende 20.2 des Gasanschlussstutzens 20 bei Figur 2. Mit anderen Worten: Beim Beispiel gemäß Figur 2 werden der Gasanschlussstutzen 20 und die anschließende Gaszuführ-Leitung 30 über eine Steckverbindung miteinander verbunden.
• Die Gaszuführ-Leitung 30 gemäß Figur 2 ist zwischen den Enden (30.1, 30.2) nicht als Rohr (wie bei Figur 1) sondern als dickwandiger Zylinder gestaltet und erfüllt gleichzeitig die Funktion einer Durchbruchsicherung. Dazu ist der Gaskanal 26 zwischen zweitem Ende 30.2 und erstem Ende 30.1 nach Art einer Wendel (oder Spirale) gestaltet. Sollte Metallschmelze in den Gaskanal 26 eindringen würde diese radial nach außen (entlang der Wendel) geleitet, der Weg für die Schmelze also verlängert, um die Schmelze schneller abkühlen zu können, bis sie erstarrt. Dies ist vom Prinzip her bekannt und wird hier nicht näher beschrieben.
• Das erste Ende 30.1 der Gaszuführ-Leitung 30 gemäß Figur 2 ist analog zum ersten Ende 20.1 des Gasanschlussstutzens 20 gemäß Figur 1 gestaltet und dient zum Anschluss einer weiteren Gaszuführ-Leitung 70, die analog zur Gaszuführ-Leitung 30 gemäß Figur 1 gestaltet ist.
• Das ringförmige Element 64 der Montagevorrichtung 60 liegt in der Montageposition direkt gegen die Unterseite des dickwandigen Teils der Gaszuführleitung 30 an.
• Die Figuren 2a-d zeigen einzelne Montageschritte für diese Ausführungsform. Zuerst wird der Gasspülstein 10 (mit angeschlossenem Adapter 20) im Boden des metallurgischen Gefäßes eingebaut (Figur 2a).
• Die Montagevorrichtung 60 ist geöffnet.
• Dann wird die Gaszuführ-Leitung 30 einschließlich Durchbruchsicherung auf den Adapter 20 aufgesteckt und verschraubt (Figur 2b). Danach wird die Montagevorrichtung über beide Teile 20, 30 verschwenkt (Figur 2c) und der Teil 30 gesichert.
• Im letzten Schritt wird die weitere Gaszuführ-Leitung 70 mit ihrem oberen Ende 70.2 auf den unteren Abschnitt 30.1 der Gaszuführ-Leitung 30 aufgesteckt und über ein Schraub-Sicherungselement gesichert, analog wie bei den Enden 20.1, 30.2 (Figur 2d).

This also applies to the embodiment according to FIG. 2 , It differs from the variant according to FIG. 1 especially in the following features:

• the gas connection piece 20 is formed in the manner of an adapter, which is fastened to the metal base 14 of the gas purging plug 10 (here: welded on). The adapter is only 10 mm down over the bottom 14 and at this end (20.1) similar to the first end 20.1 of the gas connection piece 20 according to FIG. 1 designed. Analogously, this applies to the second end 20.2 of the gas connection piece 20 at FIG. 2 , In other words: In the example according to FIG. 2 the gas connection piece 20 and the subsequent gas supply line 30 are connected to one another via a plug connection.
• The gas supply line 30 according to FIG. 2 is not between the ends (30.1, 30.2) as a tube (as in FIG. 1 ) but designed as a thick-walled cylinder and simultaneously fulfills the function of a break-through protection. For this purpose, the gas channel 26 between the second end 30.2 and the first end 30.1 in the manner of a helix (or spiral) designed. Should molten metal penetrate into the gas channel 26, this would be directed radially outwards (along the helix), thus extending the path for the melt so that the melt can be cooled more rapidly until it solidifies. This is known in principle and will not be described here.
• The first end 30.1 of the gas supply line 30 according to FIG. 2 is analogous to the first end 20.1 of the gas connection piece 20 according to FIG. 1 designed and used to connect a further gas supply line 70, which is analogous to the gas supply line 30 according to FIG. 1 is designed.
• The annular element 64 of the mounting device 60 is in the mounting position directly against the bottom of the thick-walled part of the gas supply line 30 at.
• The FIGS. 2a-d show individual assembly steps for this embodiment. First, the gas purging plug 10 (with adapter 20 connected) is installed in the bottom of the metallurgical vessel ( FIG. 2a ).
• The mounting device 60 is open.
• Then the gas supply line 30 including breakthrough protection is plugged onto the adapter 20 and screwed ( FIG. 2b ). Thereafter, the mounting device is pivoted over both parts 20, 30 ( Figure 2c ) and the part 30 secured.
• In the last step, the further gas supply line 70 is plugged with its upper end 70.2 on the lower portion 30.1 of the gas supply line 30 and secured by a screw-fuse element, analogous to the ends 20.1, 30.2 ( Figure 2d ).

Claims (8)

1. Gas purging device for metallurgical applications comprising a gas supply pipe and a gas purging element (10) with the following characteristics:

   a) The gas purging element (10) features a ceramic fireproof body (10k) with a first end (10u) and a second end (10o),

   b) the second end (10o) is in the mounted position of the gas purging element in contact with the metal melt,

   c) the first end (10u) is covered by a metal coat (12), which features an opening (16) to which a gas connection adapter (20) connects,

   d) the gas purging element (10), the body (10k) and the gas supply adapter (20) are designed in such a way that a treatment gas which is supplied via the gas supply adapter (20) flows through the body (10k) and exits the body (10k) at the second end (10o),

   e) the gas supply adapter (20) is connected to a metal coat (12) and at its free end (20.1) designed as a plug or socket of a push-fit connection for the connection to a corresponding socket or a corresponding plug of a the gas supply pipe (30), as well as

   f) a secure element (40) with an inner screw thread (42i), mechanically securing the push-/fit connection according to a cap nut together with a corresponding outer screw thread at the free end (20.1) of the gas supply adapter (20).
2. Gas purging device according to claim 1, wherein the gas supply adapter (20) extends away from the ceramic body (10k), starting from the connection area (22) to the metal coat (12).
3. Gas purging device according to claim 1, wherein the gas supply adapter (20)extends towards the ceramic body (10k), starting from the connection area (22) to the metal coat (12).
4. Gas purging device according to claim 1, wherein the gas supply adapter (20) which is designed as a plug features one of the following geometric shapes on the outside: cone, frustocone, prism.
5. Gas purging device according to claim 1, wherein the gas supply adapter (20) which is designed as a socket features one of the following geometric shapes on the outside: negative cone, negative frustocone, negative prism.
6. Gas purging device according to claim 1, wherein the gas supply adapter (20) features a break-through protection against invading metal melt.
7. Gas purging device according to claim 1, wherein the gas supply adapter features a back pressure valve (26, 28).
8. Gas purging device according to claim 1 whose gas supply adapter (20) features a length, in the direction of the stream (G) of the supplied gas, of less than 20cm.

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