WO2014206761A2

WO2014206761A2 - Two-dimensional oscillation of a continuous casting mould

Info

Publication number: WO2014206761A2
Application number: PCT/EP2014/062303
Authority: WO
Inventors: Guenter Leitner; Martin MUEHLBACHLER; Josef Watzinger
Original assignee: Siemens Vai Metals Technologies Gmbh
Priority date: 2013-06-27
Filing date: 2014-06-13
Publication date: 2014-12-31
Also published as: CN105517729A; KR102195755B1; WO2014206761A3; EP3013499A2; EP3013499B1; AT514495B1; AT514495A1; KR20160027047A

Abstract

The invention relates to a method and a device for oscillating a mould (1) of a continuous casting machine. The object of the invention is to provide a method for oscillating a mould (1) of a continuous casting machine, wherein the strand is better lubricated by the casting powder, and the strand has fewer oscillation marks. To achieve this object, at least one long-side plate (3, 3a, 3b) of the mould (1) oscillates horizontally in the direction of the length (H) of the long-side plate (3, 3a, 3b) with f _H , where f _v ≠ f _H , and for all points of the locus curve of the long-side plate (3) the magnitude of the velocity ΙvΙ is greater than 0.

Description

description

Two-dimensional oscillation of a continuous casting mold. Field of technology

The present invention relates to a method and apparatus for oscillating a mold of a

Continuous casting machine (also called continuous casting mold).

On the one hand, the invention relates to a method for

Oscillating a mold of a continuous casting machine, wherein the mold comprises two narrow-side and two wide-side plates, and the mold oscillates in the vertical direction relative to a stationary support structure with a first frequency f _v .

On the other hand, the invention relates to a device for oscillating a mold of a continuous casting machine,

including

the mold having a substantially rectangular mold cavity, the mold comprising two narrow side plates and two wide side plates; and

- A first oscillation device for oscillation of the mold relative to a stationary support structure in the vertical direction.

PRIOR ART In continuous casting, it has been known for a long time to oscillate a mold one-dimensionally in the vertical direction in relation to a stationary support structure. On the one hand, the forming in the mold strand is lubricated by the discontinued on the liquid steel casting powder;

On the other hand, the adhesion of the strand to a

Copper plate prevents the mold. By the

one-dimensional oscillation of the mold, the strand exhibits so-called oscillation marks, which are the strand quality due to transverse cracks, casting powder, locally changed heat dissipation or unfavorable microstructure negatively influence. It is further known that the continuous casting process or the quality of the strand by the use of optimized casting powder or by optimized parameters of Kokillenoszillation

(Amplitude, frequency, sinusoidal or non-sinusoidal

Curve shape) can be improved.

It is also known from JP 2000042691 A, a

Make broad side plate of a slab mold in a circular or elliptical oscillation. The disadvantage of this is that the broadside plate with a relatively high

Frequency (equal to the frequency of the oscillation in the vertical direction) oscillates, and that at the circular

Oscillation the amplitudes for the vertical and the

horizontal oscillation must be the same. Furthermore, the length of the locus is relatively short. Due to the high complexity, the method or device is difficult to use in practice.

Summary of the invention

The object of the invention is to overcome the disadvantages of the prior art and a method and a

Apparatus for oscillating a mold of a

To represent continuous casting machine, with which the strand is better lubricated by the casting powder and the strand has fewer oscillation marks. In addition, the device according to the invention should be simpler than known devices for a two-dimensional oscillation.

This object is achieved in the aforementioned method in that at least one broad side plate (preferably both wide side plates) of the mold horizontal in

Width direction of the broadside plate with a second

Frequency f _H oscillates, where f _v Ψ f _H , and

that for all points of the locus of the broadside plate the magnitude \ v \ of the velocity is greater than 0. In the evaluation of two-dimensional oscillation patterns (locus curves), it has surprisingly been found that it is particularly favorable when the frequencies for the

Vibrations in the vertical and horizontal directions are different. As a result, the length of the locus is extended at an oscillation cycle, which has a very positive effect on the lubricating effect of the casting powder.

In addition, the strand and the broadside plate are loaded very evenly. In addition, it is very favorable that the locus of the broadside plate of the mold has no dead points (i.e., points for which the magnitude of the velocity is zero, i.e., \ v \ = 0). This will be a

Direction reversal of the broadside plate prevented.

In a two-dimensional oscillation, the magnitude of the velocity v with the velocity components v _H in the horizontal direction and v _v in the vertical direction is calculated by \ v \ = v, + V _y .

A simple synchronization between the oscillations in the horizontal and vertical directions is possible, if the first frequency f _v is an integer multiple of the second frequency f _H , f _v = nf _H with n E {2,3,4, 5 .. .} or

- The second frequency f _H is an integer multiple of the first frequency f _Vl f _H = nf _v with n E {2,3,4, 5 ...}.

In this case, a broad side plate of the mold is oscillated in the vertical direction with the first frequency f _v , either an integer multiple of the second frequency of the

horizontal oscillation f _H is (for example, two, three, four times, etc.), or in which the second frequency f _{H is} an integer multiple of the first frequency of the vertical oscillation f _v .

The largest possible length of the locus during

Oscillation cycle is achieved, if applicable - the first frequency f _v is not an integer multiple of the second frequency f _H , f _v ^ nf _H with n E {2,3,4, 5 ...}, or

- The second frequency f _H is not an integer

Multiples of the first frequency f _Vl f _H ^ nf _v with n E {2,3,4, 5 ...}.

In addition to the oscillation of the entire mold

(including the wide side panels) in vertical

Direction according to the invention at least one

Wide side plate, preferably both wide side plates, of the mold horizontally in the width direction of the wide side plate (i.e., in the width direction of the strand, wherein the

Width direction is normal to the casting direction and thickness direction) oscillates. By limiting that for all points of the locus of the broadside plate the amount of velocity is> 0, \ v \> 0, it ensures that the trajectory of the broadside plate is smooth and has no dead spots. As a result, the direction reversal of the mold, which is particularly stressful for the lubrication of the strand, is avoided. Thus, with the same quality of the casting powder, a more efficient lubrication of the strand can be achieved. On the other hand, in the method according to the invention with the same lubricating effect, the casting speed - and thus the productivity - can be increased. Since the frequency of the oscillation is cubic in the

Energy consumption is received, the energy consumption for the horizontal oscillation is particularly low when the first frequency f _{v is} greater than the second frequency f _H , ie, f _v > f _H.

Additionally or alternatively, it is favorable if the amplitude of the vertical oscillation is greater than or equal to the amplitude of the horizontal oscillation. This can also reduce the energy consumption for the horizontal oscillation.

To prevent "tumbling" of the mold, it is

advantageous if the two broad side plates of the mold oscillate in opposite directions, ie have a phase difference of substantially 180 °. Due to the opposite movements of the mass balance of the mold is improved. Of course it is also possible that the two

Wide side plates of the mold oscillate in the same direction, i. have a phase difference of substantially 0 °.

In principle, it does not matter whether the method according to the invention is used in a straight or a curved mold. Furthermore, the method is not limited to vertically oscillating molds; Rather, it could also for horizontally oscillating molds (so-called.

Horizontal systems) can be used.

The object of the invention is also achieved by the device mentioned, wherein a second

Oscillation device for oscillation of at least one

Wide side plate of the mold is provided opposite the adjacent narrow side plates in the horizontal direction, and the wide side plate slidable relative to the

adjacent narrow side plates is formed.

Since the derivation of a harmonic oscillation again represents a harmonic oscillation, a smooth locus for the broadside plate is achieved when the

Wide side plate horizontally in the width direction of the

Wide side plate oscillates harmoniously. It is particularly preferred if the vertical oscillation is also harmonious.

In addition to the first oscillation device for the oscillation of the mold in the vertical direction, the device according to the invention has at least one second oscillation device for horizontal oscillation of at least one

Wide side plate of the mold opposite the adjacent ones

Narrow side plates in the width direction of the wide side plate. By the oscillation of the mold in vertical and horizontal direction is improved at the same casting speed, the lubricating effect of the casting powder on the strand.

It is advantageous if each of the two wide side plates is assigned its own second oscillation device for horizontal oscillation in the width direction. As a result, the mass balance of the mold can be improved.

In order to reduce the energy consumption for the oscillation of the mold in the vertical direction, it is advantageous if the first oscillating device at least a first

elastic element and a first oscillation drive, wherein the first elastic element and the first oscillation drive each with the mold and the

stationary support structure are connected.

A simple construction for the second

Oscillating means results when the mold comprises a mold frame and the second oscillating means comprises a second oscillating drive, wherein the second

Oscillation drive on the one hand with the vibrating in the vertical direction mold frame and the wide side plate

connected is. The energy consumption for the horizontal oscillation of the

Wide side plates can be reduced if a second elastic element between the mold frame and the

Wide side plate is arranged, and the wide side plate can be offset by the second oscillating drive relative to the vertically oscillating mold frame in a horizontal oscillation in the width direction.

It is expedient here if the second elastic element is a spring band or a helical spring.

Especially for smaller strand formats (billet or

Vorblockformate), it is advantageous if a first and / or a second oscillation drive is a linear electric motor. Due to the high power density, it is advantageous if the electric linear motor is a piezoelectric actuator. For larger formats, it is expedient if a first and / or a second oscillation drive is a hydraulic linear motor, such as a hydraulic cylinder.

To the friction and thus the energy consumption for the

Keeping horizontal oscillation low is what it is

advantageous if the broadside and the adjacent

Narrow side plates sliding surfaces, preferably made

Sintered metal, which allow a relative movement. The friction and the energy consumption for the horizontal

Oscillation can also be kept low, when the first wide side plate with the fixed side and the second wide side plate are connected to the loose side of the Kokillenrahmens, the Losseite is connected via a hydraulic clamping unit with the fixed side, and

Preferably, the clamping force of the clamping unit, more preferably hydraulically adjustable. Here, the clamping force can be e.g. hydraulically by means of the loading of the clamping unit by different high hydraulic pressures, easily adjusted.

Brief description of the drawings

Further advantages and features of the present invention will become apparent from the following description of non-limiting embodiments. The figures show:

1 shows a representation of a non-inventive

Trajectory of a broadside plate at a

one-dimensional (1 D) oscillation 2a, 2b each show a representation of a non-inventive trajectory of a broadside plate at a

two-dimensional oscillation Fig. 3-4 is a representation of a variant of the

movement path of a broadside plate according to the invention in a two-dimensional oscillation

5 shows various perspective views (FIG. 5 obliquely from above, FIG. 6 obliquely from below, FIG

Lot side of the mold frame; and FIG. 8 with a

Detailed view of the oscillation device for a broad side of the mold) of an embodiment of a device according to the invention for the two-dimensional oscillation of the mold.

Description of the embodiments

1 shows a locus curve (also called movement path) for a broad side of a vertically oscillating mold according to the prior art in a one-dimensional oscillation. From the locus, it is immediately apparent that the direction of movement of the mold - and thus also of the broad side plate - reverses at top dead center OT and bottom dead center UT, respectively; further applies to the

Speed v of the mold in the two dead centers OT and UT v = 0. In addition, the acceleration of the mold at the dead centers OT and UT has just a maximum (if, for example, applies to the path s in the vertical y direction s = A. sin ( eL>. t) holds for the velocity v and the acceleration av = s = A. ω. COS (<D. t) and a = s = -A. ω ^2. sin (ω. t)

Acceleration a with \ a \ = Α.ω ² and the associated high frictional forces in the dead centers OT and UT becomes the

Strand shell or the casting powder, which is to ensure adequate lubrication of the strand in the mold, particularly high loads in these points.

FIGS. 2a, 2b show a noninventive embodiment

Trajectory of a two-dimensional oscillating Wide side plate (vertical oscillation and horizontal oscillation in the width direction of the broad side plate) of a mold. FIG. 2 a shows the time sequence of

Oscillation (abscissa in seconds); FIG. 2b shows the locus of the movement path. For the trajectory in

vertical V and horizontal H direction (each in mm)

H = 90 °)

The locus in Figure 2b has two distinct dead centers OT, UT, so that the strand is heavily loaded at these points.

3a, 3b show the trajectory and the locus of a broad side of a mold for slab cross sections, which oscillates two-dimensionally (ie, vertically and horizontally in the width direction of the broad side plate) according to the invention. The parameters of the oscillations are f _H = 33.3 / 60 Hz, f _v = 100/60 Hz, A _H = 2 mm, A _v = 4 mm and 0 = 90 °. From the locus shows that the trajectory has no dead points and is therefore favorable.

FIGS. 4a, 4b show a further invention

Trajectory for a broadside plate of a mold. The parameters of the oscillations are f _H = 170/60 Hz, f _v = 100/60 Hz, A _H = 2 mm, A _v = 4 mm and 0 = 90 °. Also from this

Nyquist plot shows that the trajectory does not have dead points and is significantly longer in comparison to FIGS. 3a, 3b (neither f _H / fv nor f _v / f _H is an integer multiple). It is therefore extremely cheap.

From FIGS. 3 and 4 it can be seen that the movement paths according to the invention of the broad side plates of the mold are substantially smoother than in the case of the vertical, one-dimensional

Oscillation, in which the mold reverses the direction of movement both at the top and bottom dead center. Furthermore, the trajectories of the invention have no pronounced dead centers with direction reversal. Due to the smoother trajectory, the lubricating effect of

Gießpulvers improved or reduces the friction between the mold and the strand.

FIG. 5 schematically shows a mold 1 of a continuous casting machine for slab formats. In the sense of a simple representation, the oscillation device for the vertical oscillation of the mold (including the stationary support structure, the spring strips between the

Supporting structure and the mold frame 6 and the first oscillation drive for the vertical oscillation of the mold 1) not shown. The concept of vertical mold oscillation has been known to the person skilled in the art since 1921 (Van Ranst); Hydraulic oscillation devices have been known since 1962 (Koopers). Furthermore, the means for vertical oscillation of the mold are also known from the literature, e.g. out

The Making, Shaping and Treating of Steel (MSTS),

Casting Volume, chap. 15 (especially 15.6.8.1-15.6.8.4), AISE, 2003.

FIG. 8 shows the second oscillation device 5 in greater detail. A rectangular, the two Breitseiten- 3, 3a, 3b and narrow side plates 2 of the mold 1 enclosing mold frame 6 is brought by the not-shown first oscillating means in a vertical oscillation V. The two narrow side plates 2 and the two wide side plates 3 form the rectangular mold cavity 4 (for the invention, it does not matter if the

Mold cavity 4 is square or not; in particular, a wide-side plate does not have to be longer than one

Narrow side plate). By a second each

Oscillating 5a, 5b is a broad side 3a, 3b relative to the vibrating in the vertical direction V.

Mold frame 6 horizontally in the width direction H (that is, in the width direction of the strand) of the wide side plate 3a, 3b oscillates. According to Figure 7, the second is based

Oscillation drive 7, as the hydraulic cylinder. 9

is formed on the mold frame 6 and acts as a spring band pronounced second elastic element 8. About the spring band, the broad side plate 3 is brought together with the support plate 10 and the water tank 11 of the mold 1 in a horizontal oscillation H transverse to the thickness direction of the strand. The adjoining the broad side plate 3 narrow side plates 2 are not oscillated in the horizontal direction, but oscillate together with the mold frame 6 in the vertical direction V. To the friction between the

Wide and narrow side plates 3, 2 to keep low, the plates each have sliding surfaces 12 made of sintered metal. The clamping unit 15 incl. The non-illustrated hydraulic clamping cylinder ensures that the

Mold cavity 4 is sealed fluid-tight, but without causing excessive friction between the plates. Although in Figures 5 and 8 each broadside plate 3a, 3b associated with a separate second oscillation device 5 (and thus the two wide side plates in opposite directions

It would also be possible to have the horizontal oscillatory motion for both

Wide side plate 3a, 3b over only a single second

Oscillating drive 5 to accomplish. In addition, depending on a second oscillatory drive 5 in the width direction

be arranged on both sides of the wide side plate 3. To excessive friction between the water tank 11, which is connected via the support plate 10 with the wide side plate 3a or 3b, and the fixed 13 and Losseite 14 of

To avoid chill frame 6, the water box 11 either does not rest on the support structure 6 (e.g., there can be a gap between the water box 11 and the water tank 11)

Support structure 6 may be provided), or it is

Sliding surfaces 12 between the water tank and the

Support structure provided. In Fig. 6, the mold 1 is shown obliquely from below, wherein the forming in the mold 1, not

shown, strand is supported by a plurality of castors 16.

7 shows a representation of the mold 1 without the

Los side 14 (see FIG. 6) of the mold frame 6. The loose side 14 of the mold 1 is braced by the two clamping units 15 with the fixed side 13. Here, the clamping force is hydraulically adjustable.

Although the invention in detail by the preferred

While embodiments have been further illustrated and described, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the present invention

To leave invention.

LIST OF REFERENCE NUMBERS

1 mold

2 narrow side plate

3, 3a, 3b wide side plate

4 mold cavity

5, 5a, 5b second oscillation device

6 mold frame

7 second oscillation drive

8 second elastic element

9 hydraulic cylinders

10 support plate

11 water tank

12 sliding surface

13 fixed side

14 lottery page

15 clamping unit

16 castors f frequency

H horizontal width direction

OT top dead center

UT lower dead center

V vertical direction

Claims

claims

1. A method for oscillating a mold (1) of a

Continuous casting machine, wherein the mold (1) comprises two narrow side (2) and two wide side plates (3, 3a, 3b), and the mold (1) in the vertical direction (V) oscillates with respect to a stationary support structure with a first frequency f _v characterized,

in that at least one broadside plate (3, 3a, 3b) of the mold (1) oscillates horizontally in the width direction (H) of the broadside plate (3, 3a, 3b) at a second frequency f _H , where f _v f _H , and

that for all points of the locus of the broadside plate (3) the amount of velocity \ v \ is greater than 0.

2. The method according to claim 1, characterized in that

- the first frequency f _{v is} an integer multiple of the second frequency f _H , f _v = nf _H with n E {2,3,4, 5 ...}, or

- The second frequency f _{H is} an integer multiple of the first frequency f _v , f _H = nf _v with n E {2,3,4, 5 ...}.

3. The method according to claim 1, characterized in that

- the first frequency f _{v is} not an integer multiple of the second frequency f _H , f _v ^ nf _H with n E {2,3,4, 5 ...}, or

- the second frequency f _{H is} not an integer multiple of the first frequency f _v , f _H ^ nf _v with n E {2,3,4, 5 ...}.

4. The method according to any one of claims 1 to 3, characterized in that the first frequency is greater than the second frequency, f _v > f _H ■

5. The method according to any one of claims 1 to 4, characterized in that the amplitude of the vertical oscillation greater than or equal to the amplitude of the horizontal

Oscillation is.

6. The method according to any one of claims 1 to 5, characterized in that the two wide side plates (3, 3a, 3b) of the mold (1) in the horizontal direction (H) oscillate in opposite directions.

7. The method according to any one of claims 1 to 5, characterized in that the two wide side plates (3, 3a,

3b) of the mold (1) in the horizontal direction (H) oscillate in the same direction.

8. The method according to any one of the preceding claims, characterized in that the broad side plate (3, 3a, 3b) oscillates horizontally in the width direction (H) of the broadside plate harmoniously.

9. Device for oscillating a mold (1) of a

Continuous casting machine, comprising

- The mold (1) having a substantially rectangular mold cavity (5), wherein the mold (1) comprises two narrow side (2) and two wide side plates (3, 3a, 3b);

- A first oscillation device for oscillation of the mold (1) relative to a stationary support structure in the vertical direction (V);

marked by

- A second oscillation device (5) for

horizontal oscillation of at least one broad side plate (3, 3a, 3b) of the mold (1) opposite the adjacent ones

Narrow side plates (2) in the width direction (H) of

Wide side plate (3, 3a, 3b), wherein the broad side plate (3, 3a, 3b) displaceable relative to the adjacent

Narrow side plates (2) is formed.

10. The device according to claim 9, characterized in that the device comprises two second oscillation means (5a, 5b), wherein each second oscillation means for horizontal oscillation of a broad side (3, 3a, 3b) of the mold (1) formed in the width direction (H) is.

11. Device according to one of claims 9 to 10, characterized in that the mold (1) a mold frame (6) and the second oscillation device (5, 5a, 5b) comprises a second oscillation drive (7), wherein the second oscillation drive (7) on the one hand with the in the vertical direction (V) oscillating mold frame (6) and the

Wide side plate (3) is connected.

12. Device according to claim 11, characterized in that the second oscillation device (5, 5a, 5b) comprises a second elastic element (8) which is arranged between the mold frame (6) and the wide side plate (3, 3a, 3b), wherein the broad side plate (3, 3a, 3b) by the second oscillating drive (7) relative to the in

vertical direction (V) oscillating mold frame (6) in a horizontal oscillation in the width direction (H) of the broad side plate (3, 3a, 3b) can be added.

13. The apparatus according to claim 12, characterized in that the second elastic element (8) is a spring band.

14. Device according to one of claims 11 to 13, characterized in that a second oscillation drive (7) is a linear motor.

15. The apparatus according to claim 14, characterized in that the linear motor is a hydraulic linear motor,

preferably a hydraulic cylinder (9), or a linear electric motor, preferably a piezoelectric actuator, is.

16. Device according to one of claims 9 to 15, characterized in that between the wide side plate (3, 3a,

3b) and the mold frame (6) a support plate (10) and a water tank (11) are arranged.

17. Device according to one of claims 9 to 16, characterized in that the broad side plate (3, 3a, 3b) and the adjacent narrow side plates (2) sliding surfaces (12), preferably made of sintered metal, having a

Allow relative movement.

18. Device according to one of claims 9 to 17, characterized in that a first wide side plate (3a) with the fixed side (13) and the second wide side plate (3b) with the loose side (14) of the mold frame (6) is connected, wherein the Losseite (14) via a clamping unit (15) with the fixed side (13) is connected, wherein preferably the

Clamping force of the clamping unit (15) is hydraulically adjustable.