EP2790855B1 - Method for maintaining and/or repairing the spout area of a metallurgical vessel - Google Patents

Description

The invention relates to a method for the maintenance and / or repair of the spout area of a metallurgical vessel, in which a sleeve which is located in a perforated brick of the metallurgical vessel and is formed essentially as a hollow cylinder is removed.

In the prior art various measures are described how a metallurgical vessel can be serviced or repaired. It will be on the EP 2 056 983 B1 , on the WO 2010/136159 A1 , on the EP 1 623 778 A1 , on the WO 2010/061022 A1 , on the EP 0 109 348 B1 , on the WO 2004/010067 A1 , on the DE 36 22 327 C2 , on the JP 2010201468 A , on the JP 9273872 A , on the JP 7060434 A , on the DE 10 2009 051 145 A1 and on the JP 8019853 A pointed.

In metallurgical plants metallurgical vessels are used, which have outlet openings for molten material. The outlet openings of such metallurgical vessels - in particular the outlet opening of Stahlgießpfannen - are lined with stone material (ie with refractory material). In the case of Stahlgießpfannen this is done by the introduction of a single casting sleeve or a combination of several sleeves in a perforated brick, which is located in the pan lining. The sleeve or the combination of sleeves is walled into the hole stone by means of mortar.

Since the material wears down and the wear of the sleeve usually expires faster than that of the lining of the pan, the need arises to renew such a sleeve or the combination of the sleeves, without having to renew the delivery of the pan. For this purpose, the old, spent sleeve is broken out of the hole stone and removed and then replaced by a new sleeve, which is walled in accordance with.

The breaking out of the sleeve or the combination of sleeves is usually carried out by a destruction of the refractory stone, usually by the use of a pneumatic hammer. The effort to remove the spent sleeve is relatively time consuming and therefore expensive. In addition, the force exerted by the jackhammer on the metallurgical vessel shocks are very disadvantageous.

The invention is therefore the object of a method of the type mentioned in such a way that it is possible to make in a shorter time and thus more cost the maintenance or repair of the spout area of a metallurgical vessel and the sleeve described or the combination of sleeves replace. Furthermore, the process should take place with less stress on the metallurgical vessel.

1. a) Einbringen mindestens eines sich radial erstreckenden Schlitzes in die Hülse, wodurch die Hülse an mindestens einer Umfangsstelle unterbrochen wird;
2. b) Hintergreifen der Hülse oder deren Segmente mit einem Zugwerkzeug;
3. c) Herausziehen der Hülse oder deren Segmente aus dem Lochstein;
4. d) Einsetzen einer neuen Hülse oder eines neuen Steinmaterials in den Lochstein.

The solution of this object by the invention is characterized in that the method comprises the steps of:

1. a) introducing at least one radially extending slot in the sleeve, whereby the sleeve is interrupted at least one circumferential location;
2. b) engaging behind the sleeve or its segments with a pulling tool;
3. c) pulling out the sleeve or its segments from the perforated brick;
4. d) Inserting a new sleeve or stone material into the hole stone.

The substantially hollow cylindrical sleeve is preferably made of stone material.

When performing step a), at least two radially extending slots are preferably inserted into the sleeve, whereby the sleeve is interrupted at at least two circumferential locations and divided into at least two sleeve segments, which are then pulled out of the perforated block in the implementation of step c) ,

Preferably, a number of sleeve segments are created by inserting radially extending slots into the sleeve which each extend at the same circumferential angle.

The introduction of the radially extending slots in the sleeve can be done by a milling operation. Alternatively, this is also a sawing provided. In the latter case, a chain saw is preferably used for introducing the radially extending slots.

The introduction of the radially extending slots in the sleeve can be carried out by a tool, wherein the tool is cooled during the cutting of the sleeve or the stone material.

The tool for introducing the radially extending slots in the sleeve can be performed in accordance with a further development of the proposed method by an automatic handling machine.

Performing the above step c) can be done by using a hook-shaped pulling tool. This hook-shaped pulling tool can be introduced with a hook-shaped handle portion through the at least one slot in the sleeve through the spout area in the interior of the molten metallurgical vessel and behind the slot in the interior of the molten metallurgical vessel so moved, in particular rotated, that the sleeve or its segments with Undercut can be grasped and pulled out.

The invention accordingly proposes a method for a metallurgical plant operation, with which the removal of refractory material or stone material from the sprue of a metallurgical vessel is possible, in particular a removal of spent casting sleeves from steel ladles.

The invention can be used particularly favorably in metallurgical vessels in the form of steel ladles, blow-steel converters, AOD converters and electric arc furnaces.

The proposed method advantageously serves to accelerate and improve the removal process for the sleeve or stone material to be replaced.

According to the described preferred embodiment of the method, a stone chain saw is inserted into the pouring channel and sawed with the cutting edge (chain) one or more slots in the sleeve. The slot is in each case up to the hole stone, so that the sleeve stone is completely interrupted at the sawing and the previously located in the stone tension - caused by the thermal expansion of the sleeve - is eliminated. If the sleeve no longer has tension as a result of the slot or slots, it can be pulled out of the perforated block relatively easily by means of a pulling tool.

To increase tool life, the tool may preferably be cooled with water, either left inside the tool or running over the cutting elements into the channel of the metallurgical vessel. Likewise, the channel of the vessel can be cooled down before the approach of the tool with water or with another cooling medium.

The extract of the slotted sleeve or its segments can be done for example by means of a hook-like tool, in which on a metal rod or pipe, a further metal piece is attached, the so in the opening of the vessel is introduced, that can be pulled by a rotation of the trigger tool, the extracting stone. Advantageously, here or the introduced into the stone slots can be used to introduce the pulling tool or to give a wider hook space.

Fig. 1

schematisch in geschnittener Seitenansicht einen Teil der Wandung einer Stahlgießpfanne mit einem Lochstein und einer verschlissenen Hülse, wobei ein Werkzeug mit dargestellt ist, das noch nicht in Arbeitsstellung ist,

Fig. 2

in der Darstellung nach Fig. 1 den Teil der Wandung, wobei jetzt das Werkzeug in Arbeitsstellung ist,

Fig. 3

die verschlissene Hülse der Stahlgießpfanne nach Bearbeitung durch das Werkzeug im Schnitt A-B gemäß Fig. 2 und

Fig. 4

ein Zugwerkzeug in der Seitenansicht, wobei eine abzuziehende Hülse mit gestrichelten Linien dargestellt ist.

In the drawing, an embodiment of the invention is shown. Show it:

Fig. 1

schematically in a sectional side view of a part of the wall of a Stahlgießpfanne with a perforated brick and a worn sleeve, wherein a tool is shown with, which is not yet in working position,

Fig. 2

in the illustration Fig. 1 the part of the wall, where now the tool is in working position,

Fig. 3

the worn sleeve of the steel ladle after machining by the tool in section AB according to Fig. 2 and

Fig. 4

a pulling tool in the side view, wherein a deducted sleeve is shown in dashed lines.

In Fig. 1 is a section of a steel ladle to see. The wall of the pan is denoted by 13, behind it is a lining 12, which encloses a perforated brick 2. In a spout area 1, a sleeve 3 is walled into the perforated brick 2. The existing stone material sleeve 3 is worn here and must be replaced.

For the purpose of removing the sleeve 3 from the perforated brick 2, the procedure is as follows:

A tool 7 in the form of a chain saw is lifted into the region of the sleeve 3, for which purpose an unillustrated handling device (robot) can be used. The chainsaw 7 has a shearing 9 over which a chain 10 runs. The chain is driven by a motor which is arranged in a housing 11.

In Fig. 2 can be seen how with the chainsaw 7, a slot is incorporated into the sleeve 3. This takes place here at two peripheral points.

The thus processed sleeve 3 is in Fig. 3 in section AB according to Fig. 2 to see. It can be seen that at each of two circumferential locations 5 a slot 4 has been introduced so that the sleeve 3 has been divided into two sleeve segments 3 'and 3 ".

After this has taken place, the sleeve segments 3 ', 3 "in the present case, in general more than two, can be pulled out of the perforated brick 2 with a pulling tool 6 with a hook-shaped grip section 8; Fig. 4 shown. Here it can be seen that two hook-shaped grip portions 8 are arranged on a rod 14, which engage behind the sleeve segments, so that they can be removed. The pulling tool can be inserted by hand or by handling device (robot) in the hole stone or in the sleeve.

Here, the sawn slots 4 can be used to introduce the hook-shaped handle portion 8 inside the metallurgical vessel. If this is done, the rod 14 to z. B. are rotated 90 °, so that the hook-shaped grip portions 8 take behind the sleeve segments, so that they can be removed (bayonet principle).

After complete removal of the sleeve 3 or its segments 3 ', 3 "can - if necessary, after preparation of the surface of the perforated brick 2 - a new sleeve 3 are used and festgemauert.

In general, with the described procedure, the removal of sleeves or worn stone material from a metallurgical vessel can take place, whereby the method can be used for a multiplicity of such vessels.

The tool 7 can be actively cooled during its use. Before or during the insertion of the slot or slots 4, the sleeve area or the area of the stone material to be removed can also be cooled.

LIST OF REFERENCE NUMBERS

1

pour-out

2

Lochenstein

3

shell

3 '

sleeve segment

3 '

sleeve segment

4

slot

5

peripheral location

6

pulling tool

7

Tool (chainsaw)

8th

hook-shaped grip portion

9

sword

10

Chain

11

Housing with motor

12

lining

13

Wall of the pan

14

pole

Claims (10)

1. Method of maintaining and/or repairing the spout region (1) of a metallurgical vessel, in which a sleeve (3) of substantially hollow-cylindrical construction located in an apertured block (2) of the metallurgical vessel is removed,
   characterised in that
   the method comprises the steps of:

   a) forming at least one radially extending slot (4) in the sleeve (3), whereby the sleeve (3) is interrupted at at least one circumferential location (5);

   b) engaging a pulling tool (6) behind the sleeve (3) or segments (3', 3") thereof;

   c) withdrawing the sleeve (3) or the segments (3', 3") thereof from the apertured block (2); and

   d) inserting a new sleeve (3) or new block material in the apertured block (2).
2. Method according to claim 1, characterised in that in the performance of step a) according to claim 1 at least two radially extending slots (4) are formed in the sleeve (3), whereby the sleeve (3) is interrupted at at least two circumferential locations (5) and is divided into at least two sleeve segments (3', 3"), which are then pulled out of the apertured block (2) when step c) according to claim 1 is performed.
3. Method according to claim 2, characterised in that a number of sleeve segments (3', 3") is produced by forming in the sleeve (3) radially extending slots (4) which each extend around the same circumferential angle.
4. Method according to any one of claims 1 to 3, characterised in that formation of the radially extending slots (4) in the sleeve (3) is carried out by a milling process.
5. Method according to any one of claims 1 to 3, characterised in that formation of the radially extending slots (4) in the sleeve (3) is carried out by a sawing process.
6. Method according to claim 5, characterised in that a chainsaw (7) is used for forming the radially extending slots (4).
7. Method according to any one of claims 1 to 6, characterised in that formation of the radially extending slots (4) in the sleeve (3) is carried out by a tool (7), wherein the tool (7) is cooled during separation of the sleeve (3).
8. Method according to any one of claims 1 to 7, characterised in that the tool (7) for forming the radially extending slots (4) in the sleeve (3) is guided by an automatic handling machine.
9. Method according to any one of claims 1 to 8, characterised in that performance of step c) according to claim 1 is carried out in that use is made of a hook-shaped pulling tool (6).
10. Method according to claim 9, characterised in that the hook-shaped pulling tool (6) is introduced by a hook-shaped grip section (8) via the at least one slot (4) in the sleeve (3) through the spout region into the interior of the metallurgical smelting vessel and is so moved, in particular rotated, behind the slot (4) in the interior of the metallurgical smelting vessel that the sleeve (3) or the segments (3', 3") can be engaged behind and pulled out.

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