EP1032481B1 - Pouring device for metallurgic vessels and a method for controlling the quantity of discharge - Google Patents

Abstract

A pouring device for metallurgic vessels, particularly for steel melts, with slide plates which can be adjusted and slid out again one behind the other in a row under a vessel opening and into which filters can be inserted, and with an immersion pipe projecting into a mold. The slide plates have a filter part which is provided with openings arranged in the casting direction and at least one solid web plate part actuators are provided by which the slide plates can be displaced in the conveying direction (x-direction) and, in addition, in the same plane, but vertical to the conveying direction (i.e., in the y-direction).

Description

The invention relates to a pouring device for metallurgical vessels, in particular for molten steel, with adjustable and in series under a vessel opening slide-out slide plates into which filters can be inserted and one into one Mold protruding dip tube and a method for controlling the Outflow of a melt.

From DE 40 12 093 for cleaning metallurgical melts, in particular of molten steel, a ceramic filter known which is made of melt through which refractory wear parts can be installed. In one embodiment are several different functions as slide plates Slide-through closure designed, one behind the other on rails Individual plates can be placed under a vessel opening and pushed out again are arranged.

The spout closure known from this document is said to be a quick and reliable one Allow clogged filters to be replaced during casting.

The disadvantage of this device is that the filter slowly clogs up during the casting operation and the resistance in the pouring opening increases continuously. The slow clogging causes an increase in the pressure loss that the filter exerts. This increase must be compensated for by opening an additional control valve, which is in a partially closed position when the filter is completely free. This device also controls the level of the mold level.
The gradual clogging of the filter further increases the filter effect, so that the degree of purity of the melt is relatively poor when the filter is completely free, but the degree of purity of the melt is relatively good when the filter is almost completely added. A constant degree of purity of the melt is therefore not possible over a longer casting time.

The replacement of a filter is only intended as a complete component. The exchange of the Filter element is connected to an interruption in the melt supply into the mold. Depending on the duration of this disruption, the casting speed must be reduced significantly in order to to be able to continue the casting operation. When re-pouring it comes strong Turbulence in the mold, which leads to a significant loss in quality of the affected Stranges leads.

A pouring device for metallurgical vessels is known from JP05318062, in which several plates are provided below the pouring opening, one of these plates is designed as a slide plate and serves to close the outlet opening. A other plate is rotatably arranged and in this are several filters - a closed one Forming filter ring - used. A diving spout follows the pouring device.

The invention has set itself the goal of a pouring device for metallurgical vessels to create, in which the flowing liquid metal is constant with uniform Flow conditions in the dip tube is filtered.

The invention solves this problem by the features of Device claim 1 and the method claim 7. The remaining claims are advantageous developments of the invention.

According to the immersion tube is closed by a slide plate, which has a filter part which is displaceable transversely to the pouring direction and which keeps the free passage cross section in the immersion nozzle constant. This is the flow rate the melt flowing through the immersion pouring tube is detected, which is also a measure of the Clogging the filter openings represents, and the slide plates are used in a suitable manner postponed.

For this purpose, slide plates are used, which have a filter part in the casting direction has arranged openings, and have at least one full-walled plate part. Furthermore, actuators are provided with which the slide plates in the conveying direction (x direction), as well as in the same plane, but perpendicular to it (i.e. in the y direction) are movable. These actuators are connected via control devices with measuring elements with which the Flow through the dip tube is detectable.

Through the individual parts of the slide plates, the filter part and the solid wall Part, the free cross-section can be increased as desired during the casting operation or zoom out.

The diameter of the openings provided in the filter part has a size of d = 0.2 to 1 mm. In an advantageous embodiment, the openings are slit-shaped with a length / width ratio of l / b = 5/1 to 8/1.

The device according to the invention enables a constant operating sequence any length of time since the filter segments can be replaced without to influence the operational process.

An additional control valve is not necessary because the control of the pouring level in the mold via the filter itself. For this, the Displacement options in the x and y direction used, or the already added filter holes are used as a closed control plate.

Due to the melt flowing out evenly from the filter part of the slide plate result in the flow channel underneath and in the mold favorable flow conditions with a positive influence on the steel quality.

An example of the invention is shown in FIG. 1.

Figure 1 shows a distributor 11, not shown, the one Has distributor pouring stone 12 with a pouring channel 13.

The distributor nozzle 11 is with an upper guide plate 21 and one in the Figure not shown lower guide plate 22 connected.

Are between the upper guide plate 21 and the lower guide plate 22 Slide plates 23 can be pushed through.

The individual slide plates have two solid walls in the present illustration Plate parts 24, which are arranged on both sides of a filter part 25. in the Filter part 25 openings 27 are provided, which are still in the left part of the figure are completely open and at least in the right part of the figure as filter part 26 are partially clogged.

The slide plates 23 act with actuators 31 in the conveying direction (x direction) and actuators 32 acting transversely to the conveying direction (i.e. in the y direction). The actuators 31 and 32 are connected to a control device 33, which with measuring elements 34 for flow rate detection and with measuring elements 35 for Level measurement are connected.

The distributor pouring stone 12 has a pouring channel 13, which is below the Slide plates as immersion tube 28 continues, which in a no further shown mold 41 protrudes.

The two actuators 31 and 32 can - as indicated - the Move slide plates 23. At the beginning of a pouring process for example, under the pouring tube a portion of the filter part 26 and a Part of the full-walled plate part 24 are located. If now in the course of Pouring the filter part slowly clogs, then the actuator 32 is actuated. This then moves the slide plates 23 in the y direction such that more filter area is released, i.e. the section of the full-walled plate part 24 under the Pouring tube is reduced. If the entire filter is clogged, the Actuators moved the slide plates in the x and y directions until again the above-described initial state is established or another desired one Position has been set. It can be seen that of course a completely close the outlet opening of the pouring tube in this way is possible.

Position list

supply

11

Distributor

12th

Manifold pouring stone

13

Pouring channel (12)

Assembly unit

21

Upper guide plate

22

Lower guide plate

23

Slide plate

24th

Full-walled plate part

25th

Filter part new

26

Filter part clogged

27

opening

28

Immersion pouring tube

Measuring and control device

31

Actuator acting in the conveying direction (x direction)

32

Actuator acting perpendicular to the conveying direction (i.e. in the y direction)

33

Control device

34

Flow measuring element

35

Level indicator

Discharge

41

Mold

d

Diameter of the filter opening

I.

Length of filter opening slot

b

Wide filter opening slot

Claims (7)

1. Pouring device for metallurgical vessels, in particular for steel melts, with sliding plates that may be placed in a row one after the other below an opening in a vessel and pushed out again, in which sliding plates filters are placed, and with a casting tube (28) projecting into a mould, wherein the sliding plates (23) exhibit a filter part (25) provided with openings (27) arranged in the direction of pouring, and at least one solid-webbed plate part (24), and an actuator (31) is provided with which the sliding plates (23) can be displaced in the direction of conveyance (x-direction), characterised in that

   a further actuator (32) is provided with which the sliding plates (23) can in addition be displaced in the same plane, but perpendicular to the direction of conveyance (i.e. in the y-direction), and

   in that the actuators (31, 32) are connected via a control device (33) with measuring elements (34) with which the flow through the casting tube (28) can be recorded.
2. Pouring device according to claim 1,
   characterised in that
   the actuators (31, 32) are connected via a control device (33) with measuring elements (35), that displays the level of the melt in the mould (41) placed behind the casting tube (28).
3. Pouring device according to claim 1,
   characterised in that
   in comparison to the surface (P) of the solid-webbed plate part (24), the surface (F) of the filter part (25) behaves, in terms of surface measure, such that F/P = 0.3 to 0.7.
4. Pouring device according to claim 3,
   characterised in that
   the filter part (25) exhibits openings (27) with a diameter (d) measuring d = 0.2 to 1.0 mm.
5. Pouring device according to claim 3,
   characterised in that
   the openings (27) are slit-shaped with a length/width ratio of 1/w = 5/1 to 8/1.
6. Method for controlling the quantity of discharge of a melt, in particular of a steel melt, which is discharged from a metallurgical vessel via a casting tube that may be closed off with sliding plates according to claim 1, characterised by the following steps:

   the melt discharged through the casting tube is conveyed through a filter

   simultaneously, the quantity of flow of the melt discharged through the casting tube is recorded, and

   the free cross-section of the filter is adjusted via the displacement of the sliding plates in the direction of conveyance (x-direction) and perpendicular thereto (y-direction), in such a way that the quantity of flow of the melt remains constant.
7. Method according to claim 6,
      characterised in that
   the filter constitutes a part of a sliding plate likewise exhibiting solid-webbed plate parts, and is only displaced in the direction of conveyance (x-direction) when the full width of the filter part of the sliding plate has been made full use of perpendicular to the direction of conveyance.

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