KR20000006247A - Strip casting apparatus - Google Patents

Abstract

PURPOSE: A metal strip casting device is provided to contact with a casting roll face in order to solidify the melting metal on the casting roll face. CONSTITUTION: The casting device comprises:a casting roll(12); metal delivering devices(13,14,15) delivering melting metal to the casting roll; a main brush device(22) a roll cleaning brush device(21) made into a second sweeper brush device(23); a long rotary barrel brush occluding with the casting roll; and a long scraper(29) occluding with the barrel brush.

Description

Strip casting apparatus

The present invention relates to a metal strip casting apparatus in contact with a casting roll face such that molten metal solidifies on the casting roll face, and more particularly, to continuous cleaning of a casting roll in such a caster.

The casting device may be a single roll caster or a twin roll caster. In a twin roll caster, a hot product is introduced between a pair of oppositely rotating horizontal casting rolls that are cooled, so that the metal shell solidifies on the moving roll face and is collected in a nip between the rolls to solidify at the exit from the roll nip. Is obtained. As used herein, the term "nip" refers to the conventional area in which the roll is most approached. The casting pool, which is injected into the nip between the rolls through a metal transfer nozzle located above the nip, defined on the casting roll surface just above the nip and defined at the end of the nip by suitable confining means, such as a pool that blocks the side plates. To form.

In order to prevent metal oxides and slag or other contaminants from accumulating on the roll surface, a cleaning device such as a brush or cleaning belt is installed on the longitudinally outer side of the roll, so that the roll surface is continuously moved before contact with the molten metal in front of the nip. It is cleaned. An apparatus of this kind is disclosed in Japanese Patent Publication No. JO3230849-A (Nippon Steel Corporation, Mitsubishi Heavy Industries KK). In this apparatus, two sets of divided roller brushes are installed on the outer surface of each cooled casting roll having a staggered set of brushes to brush across the full width of the casting roll. Japanese Patent Publication No. J01-083341-A (Nippon Steel Corporation, Mitsubishi Heavy Industries KK) also discloses a twin roll caster in which a casting roll is cleaned by a brush. Japanese Patent Application Nos. 29393/97 and 29394/97 (Nippon Steel Corporation) disclose a roll cleaning apparatus in which two cylindrical cleaning brushes are in continuous contact with a casting roll in different casting run steps. In US Pat. No. 4,793,400, a pair of similar rotating brushes are installed in a row in a drum, and the two brushes are driven in the opposite direction of drum rotation. Still other brush devices are disclosed in US Pat. Nos. 5,307,861 and 5,575,327 by Applicants of the present invention.

Although any kind of brushing device can be used to clean the roll casting surface, it is desirable to provide an auxiliary sweeper brush that can clean the main deposits of contaminants from the roll surface before performing the main cleaning brush installation and then perform a fine cleaning action. It has been found to be preferred. The sweeper brush may be in the form of a long fixed head sweeper brush with a long set of wire bristles and may be advanced or retracted so that brush loading on the roll can be varied. A simple fixed head sweeper brush of this type has a short life and can easily be damaged. The number of bristles that can be in contact with the roll face is limited by the narrow width of the brush, and deposits on the casting face can often pass through these bristles. The present invention provides an improved sweeper brush in the form of a barrel brush that can achieve even more effective brushing and longer brush life and an apparatus that does not need to drive the barrel brush to perform an effective sweeping function.

According to the present invention, a casting roll, a metal transfer means for transferring molten metal to the casting roll surface, and a main brush device extending across the roll to clean the roll surface and engage the roll in one position, and a position in front of the main brush device. 10. A metal strip casting device comprising a roll cleaning brush device comprising a second sweeper brush device extending across a roll to engage a roll face at

The device extends across the casting roll width and is adapted to rotate about its longitudinal axis, thereby scraping material swept from the barrel brush, a long rotary barrel brush that can engage the casting roll to be rotatably driven. The barrel brush has a long scraper extending along the barrel brush and engaged with the barrel brush so that the barrel brush rotates in the same circumferential direction as the casting roll face at the portion engaged with the casting roll face at a speed lower than the peripheral speed of the casting roll face. It provides a metal strip casting apparatus characterized in that.

By means of the device provided according to the invention, it is possible to use a barrel brush for the sweeping action. Barrel brushes have much higher bristle densities than equivalent long fixed head brushes, and bristles can be much shorter than conventional sweeper brushes. According to the present invention, the barrel brush can be effectively rotated with respect to the casting drum without using a complicated brush drive while simultaneously ensuring that the barrel brush is continuously cleaned to maintain the effective sweeping action.

Preferably, the apparatus of the present invention also includes a means for moving the barrel brush towards or away from the casting roll.

The barrel brush may be rotatably installed on a brush mounting structure that is connected to a fluid cylinder device operable to move the brush mounting structure toward or away from the casting roll. In this case, the scraper may be installed on the brush mounting structure to move in and out with the barrel brush.

The scraper has an elongated scraper blade that projects into the canopy of the bristles of the barrel brush.

The invention will be explained in more detail by the following specific embodiments in conjunction with the accompanying drawings.

1 shows a twin roll caster integrated with a pair of brush devices in accordance with the present invention;

2 shows one of the brush devices, and

3 is a front view of the barrel brush of the brush device.

<Description of the symbols for the main parts of the drawings>

12: casting roll 22: main brush device

23: sweeper brush device (barrel brush) 26: bristle

29: scraper blade

The twin roll caster illustrated in the figure has a main machine frame 11 supporting a pair of casting rolls 12. Molten metal is supplied from the ladle 13 to the tundish 15 through the refractory ladle exit shroud 14 during the casting operation, and through the metal transfer nozzle 16 the nip between the casting roll 12 17). The hot metal thus transferred to the nip 17 forms a pool 10 above the nip, which is held against the stepped end of the roll by the operation of a pair of hydraulic cylinder units (not shown). It is defined at the end of the roll by a pair of side closure plates 18. Since the upper surface of the pool 10 (generally referred to as the "meniscus" level) appears above the lower end of the transfer nozzle, the lower end of the transfer nozzle is immersed in the pool.

Since the casting roll 12 is water cooled, the shell solidifies on the moving roll surface and is gathered together in the nip 17 between the rolls so that the solidified strip product 19 is discharged at the roll exit. This product can be supplied to a standard coiler (not shown).

The twin roll casters described so far are described in some detail in Australian Patent No. 631728 and US Pat. No. 5,184,668 by the Applicant of the present invention in the illustrated form, and for appropriate structural details that do not form part of the present invention the patent See the publication.

According to the invention, the illustrated twin roll caster generally has a pair of roll cleaning devices, indicated by reference numeral 21, which roll outside the roll 12 to the opposite side of the nip 17. It is arranged on each side of the pair of casting rolls so as to engage the end.

Each cleaning device 21 has a frame 20 with a main roll cleaning brush 22 and an auxiliary sweeper brush 23. The main brush is in the form of a cylindrical barrel brush with wire bristles and rotary drive means 35 coupled to the brush shaft 34 to rotate the brush in the direction opposite to the rotation of the casting roll, as indicated by arrow 36 in FIG. 2. Can be rotated by Although the main brush is shown as a cylindrical barrel brush, this brush is another type, such as a long rectangular brush disclosed in US Pat. No. 5,307,861, a rotary brush device disclosed in US Pat. No. 5,575,327, or a pivoting brush in Australian Patent Application No. PO 7602. Can be taken. The exact shape of the main brush is not critical to the present invention.

According to the invention, the auxiliary sweeper brush 23 is in the form of a cylindrical barrel brush having a central body 24 supported on the shaft 25 and fitted with a cylindrical canopy of the wire bristle 26. The barrel brush shaft 25 is rotatably mounted to a brush mounting structure 27 that can be moved back and forth by the action of a fast acting hydraulic cylinder 28 to move the barrel brush inward relative to the roll 12. Or retract away from the roll. The roll mounting structure 27 is in the form of a wide yoke having a side wing 30 on which a brush shaft 25 is rotatably mounted to a bearing 31. Since the barrel brush 23, the brush mounting structure 27 and the actuator 28 are supported on the main frame 20 of the cleaning device 21, the barrel brush will always be positioned correctly before the main brush 22. The roll mounting structure 27 supports an elongated scraper blade 29 that extends across the width of the barrel brush 23 and protrudes into the canopy of the bristles 26. The blade 29 may be formed of hardened iron and may have sharp leading edges. In the apparatus, as shown by arrows 32 and 33 in FIG. 2, the canister of the bristle 26 when the brush 23 is biased inwardly with respect to the roll 12 by the operation of the cylinder unit 28. Since it is rotatably driven by frictional engagement between the blood and the roll surface, it rotates in the same peripheral direction as the roll surface at the portion engaged with the roll surface. Since the rotation of the barrel brush 23 is delayed by interlocking with the scraper blade 29, the barrel brush 23 is driven at a slower peripheral speed than the roll. Due to the relative speed between the roll and barrel brush 23, it is possible to ensure that an effective sweeping action is achieved and the bristles that engage the casting roll are continuously changed. The scraper blade 29 also effectively cleans the barrel brush 23 contaminated with the swept material from the casting surface of the roll, so that the cleaned bristles are continuously provided on the casting roll surface.

The barrel brush 23 is moved in engagement with the casting roll before the casting commences and away from the roll after the casting conditions are stabilized. Retract with the roll just before casting ends. The barrel brush is used to prevent damage to the main brush and the casting roll as debris produced at the start and end of the casting continues to follow up.

Claims (12)

Casting roll 12, metal transfer means 13, 14, 15 for transferring molten metal to the casting roll 12 face, and a main brush device extending across the roll to clean and engage the roll in one position A metal strip casting device having a roll cleaning brush device (21) consisting of a second sweeper brush device (23) extending across the roll to engage the roll surface at a position in front of the main brush device (22). In the above, the sweeper brush device 23 extends across the width of the casting roll 12 and is adapted to rotate about the longitudinal axis, thereby allowing the long rotary barrel to engage the casting roll to be rotatably driven. Scraping the swept material from the brush, barrel brush 23 and impeding the rotation of the barrel brush 23, so that the barrel brush is at a speed lower than the peripheral speed of the casting roll 12 surface. Sting extend along the barrel brush 23 in the engaging portion and rolmyeon to rotate in the same direction around the barrel, and casting rolmyeon metal strip casting apparatus comprising a long scrapers 29 in engagement with the brush. 2. Metal strip casting device according to claim 1, characterized in that it comprises means (28) for moving the barrel brush (22) towards or away from the casting roll (12). 3. The brush mounting structure (27) of claim 2, wherein the barrel brush (23) is on a brush mounting structure (27) connected to a brush actuator (28) operable to move the brush mounting structure (27) towards or away from the casting roll (12). Metal strip casting device, characterized in that rotatably installed on. 4. Metal strip casting device according to claim 3, characterized in that the brush actuator (28) comprises a fluid actuated cylinder device. 5. Metal strip casting device according to claim 3 or 4, characterized in that the scraper (29) is mounted on a brush mounting structure (27) to move in and out with the barrel brush (23). 6. Metal strip casting device according to any one of the preceding claims, characterized in that the scraper (29) is fixed to the brush mounting structure (27). The brush barrel 23, the brush mounting structure 27 and the brush actuator 28 bear on a frame 20 which supports the main brush device 22. Metal strip casting device, characterized in that. 8. The cylindrical canopy of claim 1, wherein the barrel brush 23 protrudes radially outwardly from the central brush body 24 and the central brush body 24. Metal strip casting apparatus comprising a. 9. A metal strip casting device according to claim 8, wherein the bristle (26) is made of steel wire. 10. Metal strip casting apparatus according to claim 8 or 9, characterized in that the scraper (29) has an elongated scraper blade projecting into the bristle canopy of the barrel brush (23). 12. The apparatus of claim 10, wherein the scraper blades (29) have sharp leading edges. 12. A metal strip casting device according to claim 10 or 11, wherein the scraper blades (29) are made of hardened steel.