Method for separating a starter bar from a cast bar

Abstract

The invention relates to a method for separating a start-up strand (3) from a casting strand (6), e.g., in a continuous casting plant, by moving a rotatable roller (2) from a starting position (30) located below the strand guide track (20) into the strand guide track and / or beyond into a separation position (40) to lift the start-up strand (3) out of the strand guide track (20). In order to continue using the roller (2) effectively even after reaching the separation position (40), the present invention proposes moving the roller (2) from its separation position (40) into a support position (50), in which it functions as one of the support rollers for the separated casting strand (6) on the underside of the strand guide track (20).

Description

[0001] The invention relates to a method for separating a start-up strand from a cast strand according to the preamble of patent claim 1. The invention further relates to a further use for a roller for separating the start-up strand from the cast strand.

[0002] In a continuous casting plant with an arcuate strand guide section and a horizontal strand guide section arranged downstream of it, a starting strand is separated from a coupled cast strand start by pivoting a pivoting roller arranged below or above the strand guide track into the strand guide track, thereby deflecting the starting strand from the strand guide track and thereby separating it from the cast strand. Such a device is known, for example, from EP 0 035 988.

[0003] The object of the invention is to further develop a known method for separating a start-up strand from a cast strand using a rotatable and movable roller in such a way that the roller can be put to practical use even after the separation process. The object of the invention is also to expand the use of the roller accordingly.

[0004] According to the invention, this object is achieved in terms of process technology in that the roller, after the start-up strand has been separated from the start-up strand head, is displaced from a separation position into a support position in which it acts as one of the support rollers for the separated start-up strand and / or cast strand on the underside of the strand guide track.

[0005] In the claimed method, the movable roller has a dual function. On the one hand, in its separation position, it serves to push the start-up strand out of the strand guideway, thus separating the start-up strand from the cast strand. On the other hand, it subsequently supports the guidance of the cast strand on / in the strand guideway by being moved from the separation position to the support position, where it functions as an additional support roller for the separated start-up strand and / or the cast strand.

[0006] Whether it is sufficient for the roller to be moved only into the strand guideway or also beyond it to reach its separation position depends on the design of the coupling between the start-up strand and the cast strand.

[0007] The term "roller" also represents a cam on which the starting strand or the cast strand can slide.

[0008] Depending on whether the roll is moved from its separation position to the support position with a directional component in the transport direction of the cast strand or against the transport direction, the support position of the roll is upstream or downstream with respect to the separation position and with respect to the transport direction of the cast strand on the strand guide track.

[0009] Alternatively, for example, if the displacement of the roll from its separation position to its support position occurs without a directional component in the transport direction of the cast strand, i.e. perpendicular to the strand guideway, then the support position of the roll is at the level of its separation position relative to the transport direction of the cast strand.

[0010] If the roll is moved from its separation position to the support position with a directional component opposite to the transport direction of the cast strand, this can lead to a situation where, as the casting speed increases, the time available for repositioning, especially for pivoting back, the roll is no longer sufficient to safely avoid a collision with the subsequent cast strand. However, this can be avoided by ensuring a sufficiently high roll displacement speed.

[0011] Alternatively, a collision of the roll with the subsequent cast strand can be avoided by moving the roll from its separation position to the support position with a directional component in the transport direction of the cast strand, optionally while simultaneously increasing the displacement speed of the roll.

[0012] As long as the method according to the invention is not being used, the roll is stored or positioned in its initial position, which corresponds to a parking position, below the strand guide track. From there and back, the roll can be moved, for example pivoted, using a drive, for example, via a lever system and with the aid of a piston-cylinder unit.

[0013] The displacement of the roller is comparable to the movement and function of a cam, which at least temporarily displaces another mechanical component from a nominal position. According to the invention, the displacement of a roller head in which the roller is rotatably mounted takes place either in the form of a 360° rotation or pivoting movement, or preferably only within a specific angular range in which the roller head and roller are displaced back and forth.

[0014] The above-mentioned object of the invention is achieved with regard to the use by the subject matter of claim 7.

[0015] Further advantageous embodiments of the invention emerge from the subclaims, which are explained below by way of example in connection with the description of the figures.

[0016] The Figures 1 to 8 illustrate the method according to the invention in chronologically successive steps. In all figures, identical technical elements are designated by the same reference numerals. To simplify the description, only one roller 2 will be referred to below, knowing that this roller 2 is rotatably mounted in a roller head 1, which is displaced by means of the drive to carry out the method, as described by way of example in the following paragraph.

[0017] All figures show, by way of example, an identical control device for the roller for carrying out the method according to the invention and for realizing the claimed use. According to this exemplary embodiment, the control device has a roller head 1 in which the roller 2 is rotatably mounted. The roller head 1 is moved back and forth between different positions with the aid of a drive, here for example pivoted about a pivot axis 5. The drive can be in the form of a piston-cylinder unit 4 or an electric, pneumatic or hydraulic drive. The electric drive can be designed as a linear motor, for example, and replace the piston-cylinder unit shown in the figures by being hingedly connected to the roller head in the area where the piston-cylinder unit 4 is alternatively hinged.Alternatively, the electric drive can also move the roller head 1 with the roller 2 into the various positions directly or via a gear, for example by pivoting about the pivot axis 5. In the case of a direct drive, the axis of rotation of the electric drive coincides, for example, with the pivot axis 5 and the roller head 1 is connected in a rotationally fixed manner to the axis of rotation of the electric drive.

[0018] Fig. 1 shows the roller 2 in its starting position 30 below the strand guide track 20, i.e., preferably without contact with it. A freshly cast cast strand 6 is shown on the strand guide track 20 after leaving a mold (not shown in the figures). A start-up strand 3, consisting of a plurality of chain links 13, is connected to the cast strand 6 via coupling parts 7 and 8—upstream in the transport direction T.

[0019] According to Fig. 2causes a displacement, in particular a pivoting movement of the roller head 1, with a component in the transport direction T, a displacement of the roller 2 from its starting position 30 through a gap between the support rollers 22, first to the underside of the strand guide track 20 and subsequently according to Fig. 3 into the strand guide track 20, specifically into its separation position 40 shown there. This leads to a separation of the start-up strand 3 from the cast strand 6 or, more precisely, to a separation of the coupling part 7 at the start-up strand head from the coupling part 8 at the cast strand beginning. Alternatively to the Fig. 1 The position of roll 2 shown in Fig. 2 The position shown for roll 2 serves as the starting position for roll 2.

[0020] The term "strand guideway 20" refers here to a sequence or line of support rollers 22 behind a mold, on which the cast strand can be transported away from the mold after leaving the mold in a transport direction T, also called the casting direction. On the strand guideway, the starting strand 3 and the cast strand 6 are transported in a coupled state before their separation and separately from each other as individual strands after their separation.

[0021] As can be seen from the Fig. 4 to Fig. 6 As can be seen from the steps shown, the start-up strand 3 is withdrawn after separation at a greater speed in the transport direction T than the cast strand 6, which moves at casting speed in the transport direction T. The distance between the two strands 3, 6 is thereby increased as desired, at least shortly after separation.

[0022] According to the Figures 4 to 6The pivoting movement of the roll 2 in the casting direction or in the transport direction T is continued until the roll 2 is transferred to a support position 50, in which it is located outside the strand guideway 20, more precisely on its underside. In the support position 50, the uppermost point of the roll 2 is at the same height as the highest points of at least the adjacent support rolls 22 and, together with them, forms a "level" roller table for the strands 3, 6. In this support position 50, not only the subsequent cast strand 6, but also the end of the start-up strand 3 can be easily guided over the roll 2, as shown in the Figures 5 to 6 is shown. The Fig. 2 The position of the roll 2 shown is suitable as a support position; for this purpose, the roll 2 is preferably moved with one component opposite to the transport direction from its separation position to the support position.

[0023] Fig. 8illustrates the subsequent return of the roll 2 from the support position 50 to the possible starting positions 30, 30', which - as previously mentioned - preferably only takes place when the cast strand 6 has been completely withdrawn. Depending on the design of the Fig. 8 not shown drive and depending on whether the cast strand 6 is still in / on the strand guide track 20 or not, the return displacement of the roll 2 from the support position 50 to the starting position 30, 30' can take place with or without crossing the strand guide track 20.

[0024] With the help of the drive device shown in the figures, the roller 2 can, due to its design, only be moved against the transport direction T from its support position 50 back to the starting position 30 according to Figure 1With differently designed drive devices, which can, for example, perform a complete circular movement over an angular range of 360°, it would also be possible to return roller 2 while maintaining the direction of movement.

[0025] The Figures 1 to 8 show only a first embodiment for the case where the roller 2 with its control device is arranged below the cast strand 6 and the steering of the starting strand 3 from the strand path takes place in the form of a lifting. However, the present invention expressly also encompasses a second embodiment in which the roller 2 and its control device are arranged above the cast strand and the starting strand 3 is pressed downwards out of the strand guide path 20. The starting position 30 and the support position 50 for the roller would then be located above the strand guide path 20. List of reference symbols

[0026] 2Roller 3Start-up strand 6Casting strand 13Chain link start-up strand 20Strand guide track 22Support roller 30Starting position 30'Starting position 40Separating position 50Support position

Claims

1. Method for separating a start-up strand (3) from a cast strand (6), wherein the two strands are initially guided coupled to one another on support rollers along a strand guide track (20), comprising the following steps: - displacing a rotatable roller (2) from a starting position (30) located below the strand guide track (20) into the strand guide track and / or beyond it into a separating position (40) for lifting the start-up strand (3) out of the strand guide track (20) and for separating the start-up strand (3) from the cast strand (6); characterized by that the roller (2) is displaced from its separation position (40) into a support position (50) after the start-up strand (3) has been separated from the cast strand (6), in which it acts as one of the support rollers for the separated start-up strand (3) and / or the cast strand (6) on the underside of the strand guide track (20).

2. Method according to claim 1, characterized by thatthe roller (2) for lifting the starting strand (3) is moved into a gap between the support rollers in the strand guide track (20).

3. Method according to one of the preceding claims, characterized by that the cast strand (6) is cast in a mold and is drawn out of the mold into the strand guide track (20) within a strand guide device of a continuous casting plant with the aid of the initially coupled start-up strand (3); and that the support rollers (22) and the roller (2) are each strand guide rollers.

4. Method according to one of the preceding claims, characterized by that the strand guide track (20), on which the cast strand (6) initially coupled to the start-up strand (3) is guided, is formed by a roller table, and that the support rollers (22) and the roller (2) are roller table rollers.

5. Method according to one of the preceding claims, characterized by that the displacement of the roller (2) takes place, for example, in the form of a pivoting movement or a linear movement or a combination of these movements.

6. Method according to one of the preceding claims, characterized by that the roller (2) - starting from its starting position (30) - is displaced in a first direction to reach the separation position (40), in which the starting strand (3) is lifted and separated from the cast strand (6); and that the roller (2) - starting from its separation position (40) - is displaced further in the first direction or opposite to the first direction to reach its support position (50).

7. Use of a roller (2) on the one hand for separating a start-up strand (3) from a cast strand (6) and on the other hand as a support roller for supporting the start-up strand (3) and / or the cast strand (6) after their separation from one another.

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