MX2013004292A

MX2013004292A - Twin roll continuous caster.

Info

Publication number: MX2013004292A
Application number: MX2013004292A
Authority: MX
Inventors: Hiroyuki Otsuka
Original assignee: Castrip Llc
Priority date: 2010-10-18
Filing date: 2011-10-18
Publication date: 2013-06-05
Also published as: CN103269813B; EP2629907A1; MX342535B; CN103269813A; AU2011318228A1; EP2629907A4; WO2012051646A1; KR20140029361A

Abstract

In a twin roll continuous caster, the contour of the strip cast is controlled during casting by regulating the temperature of temperature-regulating medium circulated through temperature-regulating passage or passages in the casting rolls spaced inward of cooling passages in the circumferential portion adjacent the casting surfaces, The temperature-regulating passage or passages may be positioned in the circumferential portion or in the inner portion of the casting rolls, or both.

Description

DOUBLE ROLLER CONTINUOUS COLADA BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to a double-roller continuous casting machine, and more particularly to a double-roller continuous casting machine which allows the variation of the temperature of the casting rolls and the adjustment of the contour of the rolls during the casting. A double roller casting machine provides for the continuous casting of thin metal strip of molten metal.

The pair of casting rollers are positioned laterally to form a point of contact between the rollers and are compatible with a pouring tank of molten metal on the casting cylinders immediately above the contact point. The molten metal can be poured from a bucket into a smaller container, or a series of smaller containers, from which it flows through a metal feed nozzle located above the contact point, which form the pouring tank of molten metal extending the length of the contact point. This pouring tank is generally limited between the side plates, or side presses, held in sliding engagement with the end surfaces of the casting rollers in order to restrict the two ends of the pouring tank against overflow. The molten metal, supported on the casting counter-rotating rollers, is cooled on the casting surfaces of the casting rollers to form shells that meet at the constriction between the casting rollers to form the thin metal strip that is projected down from the point of contact.

The double roll continuous casting machine can be capable of continuously producing cast steel casting belt through a sequence of buckets. Pouring the molten metal from the bucket into smaller cups before flowing through the metal supply nozzle allows the exchange of an empty bucket with a full bucket without interrupting the production of the casting band.

Specifically, the double-roller continuous casting machine cools the molten metal in the adjacent tank by melting the casting surfaces of the casting rolls to form deposits on the casting surfaces, which meet at the point of contact and the thin strip solidified casting continues down the contact point between the casting rolls. To cool the casting surface of the casting rolls, the cooling water is passed through the interiors of the casting cylinders. Because the casting surfaces of the rolls are in contact with the molten metal at, for example, a temperature of 1600 ° C, the temperature of the casting rolls is regulated to provide a desired temperature and the heat flow from the molten metal in contact with the pouring surfaces of the casting cylinders. Typically, the cast rolls are maintained at a temperature of no more than about 400 ° C.

In the thin casting web by a continuous double-roller casting machine, the predictability of the crown on the casting surfaces of the casting rolls during a casting campaign is a difficulty. The crown of the casting surfaces of the casting rollers determines the thickness profile, ie the cross-sectional shape, of the thin casting band produced by the double-roll casting machine. Casting rolls with convex casting surfaces (ie, positive crown) produce the casting band with negative profile (depressed) cross section and casting rolls with concave casting surfaces (ie negative crown) produce casting band with a positive transversal profile (that is, in relief). Casting rolls are generally formed of copper or copper alloy with internal conduits for the circulation of cooling water and are normally coated with chromium or nickel to form the casting surfaces. Casting rolls undergo substantial thermal deformation with exposure to molten metal.

There is a problem where the contours of the casting rolls are altered axially and radially by the heat of the molten metal. The change in the contour of the casting rollers, in particular radially, is manifested in the thickness profile of the thin cast strip that is projected. Therefore, until now, the degree of deformation of the casting rolls during hot operation had to be foreseen before casting. Negative crowns are formed in the casting rolls, before casting, while the rolls are cold, to provide a desired casting band thickness profile taking into account the expected degree of deformation of the casting rolls during the campaign. casting to provide thin strip flat cast or thin cast strip with a small crown, as desired. However, the shape of the crown of the casting surfaces during casting conditions is difficult to predict due to changes in the temperature of the molten metal supplied to the casting tank, changes in the casting speed, even slight changes in the metal composition and other variables. Therefore, the dimensions of the negative crown applied to the cold cast rolls may not be appropriate during the casting campaign.

The variation in temperature and temperature gradient across the casting rolls causes complex deformations in the casting band in the radial and axial directions. The thickness profile of the thin cast strip is formed by the casting rolls and, especially, by the variation of the contour of the edge portions of the strip. The variation in the thickness of the portions of the edge of the thin casting band affects the quality of the thin casting band and also the hot rolling process carried out after casting.

In addition, the variation of the thickness profile of the thin casting band can be the cause of functional difficulties with the drag rollers designed to limit the deviation to the left and right of the band during rolling. Alternatively, or in addition, the variation of the thickness profile of the thin casting band may be the cause of wrinkles and cracks in the strip after rolling.

The continuous double roller wheels of the prior art also contemplate the alterations of the operating conditions during the casting campaign, eg, changing the casting speed or the volume of the molten metal in the casting tank above the point contact of the casting rollers. However, it was difficult to control and adjust changes in the contour of the casting rolls during the normal casting operation of a double roll continuous casting machine. Any change in the casting speed or the volume of the molten metal in the pouring container results in a corresponding change in the profile band. In addition, such changes in casting speed and the volume of molten metal in the casting tank also change other casting parameters, such as band gauge control, and therefore, can not be easily modified.

As described in Japanese Patent JP7-88599, it was found that the thermal deformation of the casting rolls of a double roll continuous casting machine depends on the temperature of the casting rolls, and therefore, the contour of the Casting rolls can be adjusted by altering the temperature of the casting rolls through the outer action. For example, a cast roller contour measurement instrument could be used to measure the extension of the casting drum crowns, or a cast strip profile measuring instrument could be used to measure the casting band crown. These data could be used to modify the output of a casting roller heating / cooling apparatus and thereby regulate the surface contour of the casting rolls.

As described in Japanese Patent JP7-276004, the heat flow from the molten metal to the casting rolls could be varied and the casting band crown and thickness thus could be controlled. The device attempts to control the casting crown and the thickness during casting by varying the heat flow from the molten metal to the casting rolls by using sealing gas above the casting bath and adjusting the supply temperature of gas and / or the proportions of sealing gas mixture. To achieve this temperature change, large quantities of sealing gas are needed to be supplied and adjusted. An elaborate apparatus was necessary for that purpose since the sealing gas had low thermal conductivity so it is difficult to alter the contour of the casting rolls evenly and consistently.

In addition, in the above double roller wheels, the cylindrical body of the casting rolls typically includes a main roller shaft that could be formed to be airtight and the axis of the main roller has been connected through pressure pipes to the inside of the roller. a circumferential portion of the casting roller body. The circumferential portion of the cylindrical body was typically an airtight copper sleeve with internal cooling tubes in thermal engagement with the outer circumference of the circumferential portion and preformed to impart a concave reverse crown to the central part of the molding roll to enable the hydrostatic expansion and contraction of the circumferential body portion by varying the contour of the casting roller through the pressure of the liquid. Japanese Patent No. JP7-256401 discloses adjusting the pressure of the liquid supplied to the casting rolls in such a way as to improve the degree of expansion (amount of reverse crown) of the casting rolls. However, a large, elaborate, high-pressure hydraulic device is necessary in order to control the crown by the pressure of the liquid in this manner. In addition, the contours of the casting cylinders change greatly if the liquid pressure drops (for any reason) because the contours of the casting cylinders are controlled by the pressure of the liquid.

The above description is not an admission of general knowledge common in Australia or elsewhere.

The present invention provides a double roll continuous casting machine which is capable of altering the temperature distribution on the casting surfaces of the casting rolls and adjusting the contour of the casting rolls during the casting operations.

The present invention provides a double roll continuous casting machine, comprising: a pair of casting rollers positioned laterally to form a contact point adapted to support a molten casting reservoir formed therebetween and to emit a thin descending band from between the casting cylinders; casting rolls comprising circumferential portions having a plurality of circumferential cooling passages, each having a first end portion and a second end portion, adjacent a circumferential casting surface and a passage that regulates the temperature or separate passages into the cooling passages, each having a first end portion and a second end portion; a cooler adapted to cool cooling liquid supplied to the cooling passages through inlets in the first end portions; a temperature regulation means supply unit; Y a means for regulating the temperature for supplying the unit for regulating the supply temperature to said passage or temperature regulation passages through the one entrance or entrances in the first end portions of said passage or passages and to discharge from said passages regulation of the temperature through an outlet or exits in the end portions of the second passage or passages.

The double-roller continuous casting machine described above comprises a pair of casting rollers positioned laterally to form a contact point therebetween, adapted to support a molten casting tank above the contact point and to produce a casting band. thin down from the point of contact between the cast rolls. The casting rollers comprise a circumferential portion having a plurality of circumferential cooling passages, adapted to carry cooling liquid, adjacent a circumferential casting surface and a passage or temperature regulating passages adapted to carry liquid means of regulating the temperature, separated inward from the cooling passages.

The double roller casting machine also comprises a cooling liquid circuit. The cooling liquid circuit is adapted to circulate cooling liquid which has passed through the casting rolls of the intakes in the cooling passages to a cooler, such as a cooling tower, for cooling and circulating the cooling liquid cooled from the refrigerator to inlets in the first extreme portions of the cooling passages. A flow rate regulator is adapted to regulate the flow rate through the cooling liquid circuits.

The temperature regulation passage or passages are placed in the interior of the liquid cooling ducts in the casting cylinders. A temperature regulating means, typically water, from a supply unit is distributed to the passage or temperature regulation passages through entries in said passage or temperature regulation passages and discharged through an outlet or exits in the passage or temperature regulation passages and circulates back to the supply unit. The temperature regulating means allows deformation of the extensive circumferential portion of the casting rolls, which in turn allows control of the contour of the casting rolls to be regulated during the casting operations. The deformation of the contour and casting surfaces of the casting rolls and in turn the profile of the casting strip is regulated by controlling the temperature and flow velocity of the temperature regulating medium, which is supplied to the passage. or temperature regulation passages of the casting rolls. This double roller casting machine improves the profile quality and the performance of the thin casting band formed by the casting rollers.

The temperature regulating means supply unit may further comprise a temperature regulator for regulating the temperature of the temperature regulating medium circulating through the regulating passage of the temperature or passages of the casting rolls.

In addition, the double roller continuous casting machine may further comprise a thermometer adapted to measure the temperature of the temperature regulating means to produce an output signal corresponding to the measured temperature of the temperature regulating means. Typically, the thermometer is located on or near the outlet or exits in the temperature regulation passages. A profile detector can also be adapted to measure the profile of the thin casting band and produce an output signal corresponding to the measured profile of the thin casting band. A controller may also be adapted to receive the output signal of the thermometer, the output signal of the profile detector and a target profile value of the thin casting band and regulate the temperature of the temperature regulating means to produce band of thin cast of a desired profile. The profile detector can be replaced or improved by a contour detector adapted to measure the contour of the casting surface of the casting rolls and produce a signal as an output corresponding to the measured value contour which is the input to the controller. By using a contour value input signal, the controller may be able to more precisely regulate the temperature of the temperature regulating means by the temperature regulator.

The twin roller casting machine can also comprise a first circuit for regulating the temperature of passages for circulating the temperature regulating means through the casting rollers and discharging the temperature regulating means at elevated temperature of the outlet or exits in the passage or temperature regulation passages and distributed to a refrigerator unit to cool the temperature regulating medium. The temperature regulator measures the temperature of the regulating medium of the temperature distributed to the inlet or inlets of said temperature regulation passage. A second circuit of temperature regulation passages are also adapted to circulate temperature regulating means at an elevated temperature discharged from the outlet or exits in the pathways that regulate the temperature directly to said inlet or inlets of the passageway or temperature regulation passages. and a volume flow rate regulator adapted to regulate the temperature and circulating liquid flow rate distributions of temperature regulation means between the first and second temperature regulation passages.

Alternatively, or in addition, the inner part of the casting rolls may be adapted to provide one or more temperature regulators passages for circulating the temperature regulating means. The inner part has a first end portion and a second end portion. Through a first regulator of the temperature of the circuit, the first end portion of the inner portion has an inlet adapted to receive a supply of temperature regulating medium from the supply unit and a second end portion has an outlet adapted for downloading the temperature regulating means and transmitting said data to a refrigeration unit of the supply unit. In addition, the input and output of the temperature control passages can be connected through a second temperature controller of the circuit adapted to direct the temperature regulating means from the outlet to the inlet. In any case, the supply temperature regulating means unit may include a temperature regulator adapted to regulate the temperature of the temperature regulating medium. A flow rate regulator is also provided to regulate the flow rate of the temperature regulating medium through the first and second temperature regulation circuits, as well as the flow rate distribution between the first and second temperature regulation circuits. temperature regulation circuits.

The same or additional controller may be adapted to operate with the inner part of the casting cylinders. In any case, the controller may be adapted to regulate the flow rate of the temperature regulating means by a flow rate volume of the regulator, and adapted to regulate the flow rate distribution of the regulating medium of the flowing temperature. through the first and second temperature-circuits that regulate by the same or a second volume of flow rate regulator. The controller may further be adapted to control the temperature of the temperature regulating means by a temperature regulator to regulate the temperature of the liquid medium flowing through the inner part of the casting roller. One skilled in the art will appreciate and recognize that the second controller may be integrated in the same unit as the controller to regulate the temperature regulation means used in the outer circumferential portion of the casting rolls, if provided.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram showing a double casting roller system according to the invention.

Figure 2 is a side cross-sectional representation of a double roll continuous casting machine, according to the invention.

Figure 3 is a cross-sectional front view of a casting roller provided in the double roller continuous casting machine represented by Figure 2.

Figure 4 is a front cross-sectional block diagram of a casting roller provided in the double-roller continuous casting machine of Figure 2.

Figure 5 (a) is a graph showing an example of the band thickness detection profile values, and (b) is a graph showing an example of the target profile value of the band thickness.

Figure 6 is a graph showing the amount of deformation of a casting roller cooled by cooling liquid flowing through the cooling passages.

Figure 7 is a graph showing the amount of deformation of a casting roller cooled by the temperature regulating means circulating through the passages to regulate the temperature.

Figure 8 is a graph showing the amount of deformation of a casting roller when varying the inner diameter of the circumferential portions of the casting rolls.

Figure 9 is a block diagram showing an example of a double roll continuous casting machine system with regulated flow regime liquid medium circuits.

Figure 10 is a flow diagram showing an example of the contour control of the double roller continuous casting machine system of Figure 9.

Figure 11 is a cross-sectional front view of the double roll continuous casting machine, with the inner part of the casting rolls adapted to transport a liquid medium.

Figure 12 is a cross-sectional front view of a double roller continuous casting machine of Figure 11, with the inner part of the casting roller adapted to transport a liquid medium.

Figure 13 is a front cross section of the block diagram of the casting roller of Figure 11.

DETAILED DESCRIPTION OF THE DRAWINGS With reference to Figures 2, 3 and 4, a double roll continuous casting machine 1 is disclosed having a pair of counter-rotating casting rolls 2 and 2 'positioned laterally to form a contact point that exists between and is adapted to support a molten casting tank 3 formed above the contact point along the length of casting rollers 2 and 2 '. The casting rollers 2 and 2 'cool the molten metal forming covers on the molding surface 48 of the casting rolls 2 and 2', as the casting rollers 2 and 2 'of counter-rotation and the covers meet at the point of contact to form thin strip band 4 partition down from the contact point of the casting rolls 2 and 2 '.

Casting rolls 2 and 2 'are each composed of an outer circumferential portion 40 and an inner portion 41, each circumferential portion 40 is typically composed of a sleeve 7 of copper or copper alloy, the outer surface of (normally coated with , for example, chromium alloy), which is the casting surfaces 48 of the casting roller 2 or 2 '. A plurality of cooling passages 8,8 'are provided in each circumferential portion 40 adjacent a circumferential casting surface 48 radially inwardly in the sleeve 7. The parallel cooling passages 8 and 8' are alternately positioned around each portion. circumferentially 40 and arranged so that the liquid cooling 22 circulates in opposite directions through the passages 8 and 8 'to provide for the most uniform temperature distribution suitable by the cooling liquid 22 around the casting roller. A plurality of circumferential-passj temperature regulation is 9.9 'circumferentially, separated inward from the cooling 8.8' steps disposed around each circumferential part 40. As with cooling passages 8, 8 ', the temperature regulation passages-9 and 9' are alternately arranged in parallel arrangement around each circumferential portion 40, with temperature regulating means 26 circulating in opposite directions by regulating passages 9 and 9 'to provide a more uniform temperature distribution of response by the temperature regulating means 26 around the casting roller.

The cooling liquid 22 can be introduced into the cooling passages 8 and 8 'and discharged from the cooling passages 8 and 8' through the end portion itself or opposite end portions of the casting roller 2 or 2 ', and the temperature regulating means 26 can be introduced into the temperature regulation conduits 9 and 9 'and discharged from the temperature regulation conduits 9 and 9' through the end portion itself or opposite end portions of the casting rolls 2 or 2 '. Alternatively, the entry of the two cooling passages 8 and 8 'and the temperature regulation passages 9 and 9' can to the casting rolls 2 or 2 'from portions of the opposite ends of each casting roller 2 and 2 ', as illustrated in Figures 3 and 4 and explained in detail below.

The casting rolls 2 and 2 'are each composed of a first axis 5 and a second axis 6 which axially support the casting roller, and has a first end portion 49 and a second end portion 50. To circulate liquid of cooling 22 through cooling passages 8 in the casting rolls 2, the first axis 5 and the second axis 6 have annular passages 10 and 15, respectively, which have an inlet 13 in the first end portion 49 through the rotating joint 12 and the outlet 18 in the second end portion 50 through the rotating joint 17, respectively, and for circulating cooling liquid 22 'through cooling passages 8' in the casting rolls 2 or 2 ', the second axis 6 and the first axis 5 have annular passages 15' and 10 'having an inlet 13' in the second end part 50 to 17 of the rotary joint and outlet 18 'in the first part 49 through the rotary joint 12. To circulate medium re temperature controller 26 by the temperature regulator in steps of 9 casting rolls 2 or 21, the second axis 6 and the first axis 5 have annular passages 16 and 11, respectively, having an inlet 19 in the second end portion 50 through the rotating joint 17 'and the outlet 14 in the first part 49 through the rotary joint 12' and circulate at the regulating temperature of the medium 26 'through temperature regulation passages 9' in rollers of cast 2 or 2 ', the first axis 5 and the second axis 6 have annular passages 11' and 16 ', respectively, which has an inlet 19' in the first end part 49 through the rotating joint 12 'and outlet 14 'in the second portion 50 through the rotating joint 17', respectively. Figure 3 shows a carriage 20 supporting the casting rollers 2 by the bearings 21, by which the casting rollers are compatible and rotated during the casting operation. The carriage 20 is adapted to move axially to assist in the process of placing the casting rolls 2 for casting.

Figure 1 is a block diagram showing the double roll continuous casting machine 1 according to the invention described. The casting rolls 2 can be cooled by circulating the cooling liquid 22 for the cooling of the passages 8 through the inlet 13 by the pump 23. The cooling liquid 22 is heated in the casting rolls 2 in an operation of casting (heated by the molten metal) and then cooling passages 8 through the outlet 18 in the second end part 50 of the casting roller 2 is released from the cooling. Thereafter, the cooling liquid 22 is circulated to the cooler 25, adapted to cool the cooling liquid 22, and then circulates back to the inlet 13 of the cooling passages 8. The cooler 25 typically includes a cooling tower 24. Accordingly, the casting rolls 2 are protected by the Cooling of the cooling liquid 22. During the casting campaign, the temperature of the circumferential casting surface 48 of the casting rolls 2 which is in contact with the metal The melt, which may be at a temperature of 1600 ° C, is typically maintained at no more than about 400 ° C. A similar circulation of liquid cooling 22 'may be provided for circulation through cooling passages 8'.

The temperature inside the circumferential parts 40 can be regulated by circulating the temperature regulating means 26 through the temperature regulation passages 9 of the regulation temperature of the supply unit 29 by means of the pump 27. The medium temperature regulators 26 flows from the inlet 19 in the first end portion 49 of the casting roller 2, flows through the passages to regulate the temperature 9 and is discharged from the temperature regulation passages 9 through the outlet 14 at the second end portion 50 of the casting roller 2. A temperature regulator 28 is adapted to regulate the temperature of the temperature regulating means 26 during circulation. From the supply unit 29, the temperature regulating means 26 is circulated back to the inlet 19 of the passages to regulate the temperature 9. A similar circulation of temperature regulating means 26 'may be provided to circulate through of regulation of the passages 9 'temperature.

The double roller continuous casting machine 1 of Figure 1 can have a thermometer 30, adapted to measure the temperature of the temperature regulating means 26, typically positioned close to the exits of the regulation temperature of passages 9 at the points of 14 and to produce an output signal 32 corresponding to the measured temperature. The double roll continuous casting machine 1 may further comprise a profile detector 33 adapted to detect the profile of the thin casting strip 4 and to produce an output signal 34 corresponding to the measured profile of the thin casting band 4. Alternatively, the profile detector 33 can be replaced or improved by a contour detector (not shown) adapted to detect the contour of the casting surface 48 of the casting rolls 2 and to produce an output signal corresponding to the measured contour of the casting surface 48 of the casting rolls 2. Further, a controller 30 is arranged to receive as inputs the output signal 32 of the thermometer 31, the output signal 34 (in relation to the gauge profile of measured band 34a and / or 34b measured crown value shown in Figure 5 (a)) of the detector profile 33 and / or the output signal of the contour detector and a profile destination value of the band 35 thin wash. The profile detector 33 may be composed of an X-ray emitter and an X-ray detector capable of measuring the energy of X-rays absorbed and / or diverted by the thin casting strip 4 as it passes through the profile detector 33. Figure 5 (a) shows the measurement bands of the calibrator 34a, 34b of the measured value crowns, and the approximate measurements of the profile 34c. Figure 5 (b) shows the target profile values 35 comprising the target band caliber 35a and the value profile of the target corona 35b, which may also be input to the controller 30.

To obtain the desired band profile, the controller 30 can alter the contour of the casting rolls 2 and 2 'by regulating the temperature of the temperature regulating means 26,26' distributed to the regulation of the temperature passages 9,9 'by the use of regulator 28. Controller 30 regulates the temperature on the basis of (i) the detected temperature 32 of thermometer 31, (ii) the detected value profile 34 of the thin casting band 4 from the profile detector 33 (and / or the contour value of the casting rolls 2 of the contour detector), and (iii) the target values 35 for producing thin casting band 4 of a desired profile. Referring to Figure 4, the first axis 5 of the casting rollers 2, 2 'may be a double shaft assembly with an outer ring 5a and 5b an inner ring and the second shaft 6 may also be an assembly double shaft with an outer ring 6a and 6b an inner ring. Rotary joints 12 and 12 ', and 17 and 17 'is provided connected to the ring 5a and 5b, and 6A and 6B, respectively. The cooling liguid 22 can be supplied through the rotary joints 12 to 10 annular passages (ring 5a) of the inlets 13, in the first end portion 49 of the casting rollers 2, 2 'in cooling passages 8. The cooling liquid 22 then flows through each alternate cooling step 8, then flows through the annular passages 15 (ring 6a) and discharges from the outlets 18, into the second end portion 50 of the 2, 2 'casting rollers, through the rotating joints 17. In addition, the cooling liquid 22 can be distributed to the annular passages 15' (ring 6a) and openings 13 ', in the second end part 50 of 2, 2 'casting rollers, through the rotary joints 17. The cooling liquid 22', then can circulate through alternating cooling passages 8 ', and then flow through annular passages 10', ( 5a ring) to be unloaded from the s aliases 18 ', in the first end portion 49 of casting rolls 2, 2', through the rotary joints 12. Accordingly, the cooling liquid 22 flows through the cooling passages 8 and the cooling liquid 22 it flows through the cooling of the passages 8 'in opposite directions. Alternatively, the cooling liquid 22 and 22 'in the cooling passages 8 and 8', respectively, can flow in the same direction.

The temperature regulating means 26 can be circulated through annular passages 16 (ring 6b) of the inlet 19 in the second end portion 50 of the 2, 2 'casting rollers, through the rotary joints 17. Medium The temperature regulator 26 can then be distributed through the alternating passage of temperature regulation 9 and through annular passages 11 (ring 5b) to discharge from the outlets 14 in the first end portion 49 of the casting rolls of 2, 2. 'through rotating joints 12'. Further, the temperature regulating means 26 'can be circulated to the crown of passages 11' (ring 5b) and of the openings 19 'in the first end portion 49 of the 2.2' casting rollers through the rotating joints 12 '. Temperature regulating means 26 ', then it can flow through the alternating temperature regulation passage 9' and then through the passage ring 16 '(ring 6b) to discharge from the outlets 14' in the second end part 50 of the 2, 2 'casting rollers through the rotary joints 17'. Accordingly, the temperature regulating means 26 flowing through the passages to regulate the temperature 9 and the temperature regulating means 26 'flowing through the passages to regulate the temperature 9' of opposite flows through alternate steps, the inhibition of the development of the longitudinal temperature contours in the casting rollers 2. Alternatively, the means of regulating the temperature 26 and 26 'in the passages to regulate the temperature-9 and 9', respectively, can flow in the same direction .

Figure 3 shows the cooling liquid 22 flowing through the cooling of the passages 8 of the casting rollers 2, and the temperature regulating means 26 flowing through the temperature regulation passages 9 of the rollers of cast 2, which flows in opposite directions. Alternatively, the cooling liquid 22 and the temperature adjusting means 26 can also circulate in the same direction, as shown in Figure 1. Similar circulation of cooling liquid 22 'and temperature regulation means can be provided. 'circulating through cooling passages 8' and temperature regulation passages 9 ', respectively, having the same flow or opposite directions.

Experiments have been carried out to determine the amount of radial deformation in the casting rolls 2, 2 'with the distance from the edge of the casting roll, when the temperature of the cooling liquid 22, 22' provided the cooling passages. steps of 8, 8 'was 30 ° C (X) and 80 ° C (Y) as shown in Figure 6. The results of the experiments, as shown in Figure 6, have been found that the diameter of the casting roller which can vary by changing the temperature of the cooling liquid in the vicinity of the edges of the casting rolls 2, 2 'to provide a desired profile temperature through the casting band.

Experiments were also carried out to determine the amount of radial deformation in the casting rolls 2 with the distance from the casting roller edge to the variation in temperature of the temperature regulating means 26, 26 '. The temperature of the temperature regulating means 26, 26 ', which was distributed to the temperature regulation passages 9, 9', which are separated circumferentially inwardly from the cooling passages 8, 8 'in the casting rollers of 2, 2 ', was 30 ° C (?') And 80 ° C (? ') As shown in Figure 7. The results of the experiments show that, when the casting rolls 2 are cooled through the medium of temperature regulating circulation 26, 26 'through the temperature regulation passages 9, 9', the amount of change in the casting rolls 2, 2 'was larger compared to the amount of change in the casting rolls 2, 2 'when cooled by the circulation of cooling liquid 22, 22' through the cooling passages 8, 8 ', as shown in Figure 6. In addition, the results show that the diameters of the cooling rolls 2, 2 'in the end portions were larger (i.e., crown increase amounts) as shown by X' when the temperature of the temperature control medium 26 was low (30 ° C), compared when the temperature is high (80 ° C) as shown by Y '.

In addition, experiments were performed to determine the amount of deformation in the radial direction in the casting rolls 2, 2 'when the outer diameter of the casting rolls was 500 mm and the inner diameters of the circumferential portions 40 (7 sleeves of copper) were provided with regulation of temperature-passages 9, 9 '. The wall thickness between the inner surface of the circumferential portions 40 and the temperature adjusting passages 9, 9 'varied as shown in Figure 8. The inner diameters of the circumferential portions 40 during the experiments were 350 mm, 370 mm and 390 mm. The results of the experiments, as shown in Figure 8, show that, when the inner diameter of the circumferential parts 40 was high and the thickness of the wall was small, the roller crowns on the casting rolls 2, 2 '. they were small and when the inner diameter of the circumferential parts 40 was low and the thickness of the wall was large, the roller crowns on the casting rolls 2, 2 'were large. This experiment demonstrated the increase in wall thickness provided with a greater amount of change in the contour of the casting rolls of 2, 2 '.

In general, the experiments show that large amounts of change in the contour of the casting rolls 2, 2 'can be more effectively controlled by regulating the temperature of having passages of 9, 9' in the casting cylinders near the interior of the circumferential portions 40, when the wall thickness between temperature regulated passages 9 and the inner portions of the circumferential portions 40 of the casting roller 2, 2 'is at least as thick as the thickness of the wall between cooling passages. , 8 'and the outer portions of the circumferential portions 40 of the casting roller.

In order to cast the thin casting band 4 using the double roll continuous casting machine 1, the molding surface 48 of the casting rolls 2, 2 'can be machined to, for example, the desired negative crowns according to with the casting roller contour corresponding to the desired profile of the thin casting strip 4 to be thrown. Prior to pouring, the ratio between the amount of deformation of the casting rolls 2, 2 'and the temperature of the temperature regulating means 26 distributed to the temperature regulation passages 9, 9', as shown in FIG. Figure 7, is calibrated and entered into the controller 30. At the same time, the cooling liquid 22 is determined to be distributed through the cooling passages 8 to keep the casting rolls 2, 2 'at a temperature adequate During the casting of the thin cast strip 4, the input to the controller 30 is the output signal 34 of the profile detector 33 (corresponding to the measured profile of the thin casting band 4), and the output signal 32 of the thermometer 31 ( corresponding to a measured temperature of the temperature regulating means 26, 26 'exiting the passages to regulate the temperature-9, 9' through outputs 14,14 '), and the destination profile value 35 of the thin casting band. As shown in Figure 5, the controller 30 is adapted to compare the value of the target crown 35b and the value of the crown 34b and reduces the difference by changes in the temperature of the regulated average temperature 26, 26 'circulates to through the regulated temperature steps of 9, 9 '. The controller 30 is adapted to control the temperature regulator unit 28 which in turn controls the temperature of the temperature regulating means 26, 26 'and is the basic control of the ratio between the amount of deformation of the rollers of 2, 2 'cast and the temperature of the temperature regulating means 26, 26', as shown in Figure 7.

As described above, the consistent control of the contour of the casting rolls 2, 2 'can be achieved by controlling the temperature of the temperature regulating means 26, 26' according to the relationship, which is shown in Figure 7. We have found regulation of the temperature of the temperature regulating means 26, 26 'which is circulated through the passages to regulate the temperature 9.9' has an important effect on the contour of the casting rolls of 2, 2 ' Figure 9 is a block diagram showing an example of a double roll continuous casting machine with 1 regulated circuit flow including the cooling passages 8 and the temperature regulation passages 9, respectively. The cooling liquid 22 discharged from the outlets 18 of the circumferential cooling passages 8 is distributed to and cooled by the cooler 25 (including the cooling tower 24) adapted to cool the cooling liquid 22. The cooling liquid Refrigerated 22 can then be distributed through the inlets 22 in the cooling passages 8 and cycle through the cooling of the passages 8 in a manner to cool the casting rolls 2 to a suitable temperature during a casting campaign. A similar circulation of cooling liquid 22 'may be provided by circulating through cooling passages 8'.

Also as shown in Figure 9, a portion of the temperature regulating means 26 discharged from the outlets 14 of the circumferential ones that regulate the temperature passages 9, is circulated by the pump 27 through the circulation circuit of first regulation from the temperature 36 to the cooler 25 and adapted to cool both the cooling liquid 22 and the temperature regulating means 26. The temperature regulating means 26 is circulated to the inlets 19 of the temperature regulation conduits 9. In addition , a portion of the temperature regulating means 26 is circulated in the second regulating temperature circulation circuit 37 by the pump 27, and is mixed with the temperature regulating means 26, distributed from the refrigerator 25 through the first temperature regulation circulation circuit 36, the temperature regulation of the temperature regulation means 26a which was made and circulating to the inlets 19. A similar circulation of temperature regulating means 26 'is provided with temperature regulation passage 9'.

In addition, the regulation valves of the flow rate 38 and 39 are adapted to adjust the flow rate of the high temperature of the temperature regulating means 26 flowing through the first circulation circuit of the temperature regulator 36 and the medium of temperature control 26 flowing through the second circulation circuit of temperature regulation 37, respectively. The controller 30a (similar to the controller 30) is adapted to control the opening degree of the flow rate regulating valves 38 and 39, thereby regulating the proportions of the temperature regulating means 26 of the first flow control regulation passage. temperature 36 and the temperature adjusting means 26 of the second temperature control circulation passage 37 which is mixed and introduced into the temperature regulation passage 9 through inlets 19. The controller 30a may be separate or may be part of the controller 30. A similar circulation temperature regulating means 26 'is provided with temperature regulation passage 9'.

The profile detection value 34 of the thin casting band 4, measured by the temperature profile detector 33, 32 measured by the thermometer 31 and the value of the destination contour 35 are input to the controller 30a, 30a so that the controller is adapted to control the flow rate of temperature regulating means 26, 26 'according to the flow chart shown in Figure 10. The detection value of profile 34 and the values of the contour of the target value are based on the ratio between the amount of deformation of the casting rolls 2, 2 'and the temperature of the temperature regulating means 26, 26' flows through temperature regulation passages 9, 9 '(measured at the outputs), as It is shown in Figure 7.

As shown in Figure 10, if the measured value of crown 34b is greater than the target value corona 35b, the controller 30a operatively opens the flow rate regulating valve 38 to increase the flow through it and operatively closes the regulating valve of rate of flow 39 to reduce the flow through it. The degree of opening of the valves is adjusted to reduce the temperature of the temperature regulating means 26, 26 'which is distributed to the temperature control conduits 9, 9'. The roller crowns of the casting rolls 2, 2 'are therefore larger as shown in Figure 7 and the crown of the thin casting band 4 is reduced.

Conversely, if the crown 34b measured value is less than the target corona value 35b, the controller 30a operatively opens the flow rate regulating valve 39 to increase the flow through it and operatively closes the regulating valve of flow regime 38 to decrease the flow through it. The degree of opening of the valve increases the temperature of the temperature regulating means 26, 26 'which is distributed to the passages regulating the temperature 9, 9'. The roller crowns of the casting rollers 2, 2 'are reduced as shown in Figure 7 and the crown of the band of the thin casting band 4 is increased, thereby controlling the profile of the casting band thin 4 By adjusting these parameters, the control that alters the contours of the casting rolls 2, 2 'is exerted by controlling the temperature of the temperature regulating means 26, 26' distributed to the regulation of the circumferential temperature passages 9, 9 ', which are separated inward from the cooling steps 8, 8' of the circumferential portions 7. It is possible to control large amounts of change to the contours of the casting rolls 2, 2 'with good precision and to improve the performance and the quality of the profile of the thin cast strip 4 which is cast by the double-roller continuous casting machine 1 described.

Figures 11, 12 and 13 show an alternative embodiment of a double roll continuous casting machine 1, wherein the inner portion 41 of the casting roll 2 comprises the steps of regulating the temperature. A single passage 53 can be provided for the circulation of temperature regulating means 58 through the casting roller 2 to regulate the temperature and in turn for the deformation of the casting roll 2. The temperature regulating means can typically be water. The passage 53 has a first end portion 54 with an inlet 56 and a second end portion 55 with an outlet 57. In this embodiment, as shown in Figures 11, 12 and 13, the single passageway 53 may be provided in the casting rolls 2 and 2 '. In addition, if the temperature regulating means in the outer circumferential portion is also desired, the casting rollers 2 and 2 'may have the same or different temperature regulation means circulating through temperature regulation passages in the outer circumferential 40.

In any case, the inlet 56 and the outlet 57 in the inner part 41 can be connected through a first temperature regulating circuit, the temperature regulating means circulating from the outlet 57 through the rotary seal 60 to a supply unit of temperature regulating means and of the supply unit of the temperature regulating means to the inlet 56 through the rotary joint 59. In addition, the inlet 56 and the outlet 57 can be connected through a second temperature regulation circuit adapted to direct the liquid medium from outlet 57 to inlet 56. The first and second temperature regulation circuit include one or more pumps for circulating the temperature circulation medium through the supply unit and the passage 53 in the inner portion 41 of the casting roller 2. A controller can be provided to regulate the flow rate between the first and second undo temperature regulation circuits. The controller, which may be apart from, or in addition to, the controller 30 may also be adapted to regulate the temperature of the temperature regulating means flowing through the passage 53, as well as the cooling liquid flowing through the refrigeration. of the passages 8 in the outer circumferential portions 40 of the casting rollers 2 and 2 '.

One of ordinary skill in the art will appreciate and recognize that the embodiments described herein for the cooling of the casting rolls through the inner and outer circumferential portions of the casting rolls are not exhaustive and that there are many ways of cooling the circumferential portions. inside and outside of the casting rolls that are within the spirit of the present invention.

The generality of the double roll continuous casting machine provided by the present invention is not limited to the particular embodiments thereof described above and various modifications thereof can of course always be added within the scope of the following claims.

Claims

1. - A double roll continuous casting machine, comprising: a pair of casting rollers positioned laterally to form a contact point adapted to support a molten casting tank formed therebetween and casting a thinband casting downwardly from between the casting rolls; casting rolls comprising circumferential portions having a plurality of circumferential cooling passages, each having a first end portion and a second end portion, adjacent a circumferential casting surface and a passage that regulates the temperature or separate passages into the cooling passages, each having a first end portion and a second end portion; a cooler adapted to cool cooling liquid supplied to the cooling passages through inlets in the first end portions; a temperature regulation means supply unit; Y a means for regulating the temperature for supplying from the supply unit of temperature regulating means to said passage or temperature regulation passages through an entrance or entrances in the first end portions of said passage or passages and for the discharge from said passage temperature regulation through an exit or outputs in the second end portions of the passage or passages.

2. - The double roller continuous casting machine according to claim 1, wherein a plurality of circumferential temperature regulation passages are separated inwardly from the cooling passages in the casting rolls.

3. - The double-roller continuous casting machine according to claim 1, wherein a singular circumferential passage temperature regulator is separated towards the interior of the cooling passages through the central portion of the casting rolls.

4. - The double roll continuous casting machine as claimed in any of the preceding claims, wherein the temperature regulation means supply unit comprises a temperature regulator adapted to regulate the temperature of the regulating medium of the circulating temperature through the passage or temperature-regulating passages.

5. - The double roller continuous casting machine according to claim 4, wherein the temperature regulator is a cooling water tower.

6. - The double roller continuous casting machine according to claim 4 or claim 5, further comprising: a thermometer adapted to detect the temperature of the temperature regulation means discharged from the output or outputs in the second end part of the temperature regulation passages and produce an output signal corresponding to the measured temperature of the temperature regulation means; a detector adapted to detect the profile of a measured profile of the thin strip and produce an output signal corresponding to the measured profile of the thin casting band; Y, a controller adapted to receive the output signal of the thermometer, the output signal of the profile detector and a target profile value of the thin band, and regulate the temperature of the temperature regulating medium by the temperature regulator to produce band of thin casting of a desired profile.

7. - The double roll continuous casting machine according to any of claims 1 to 3, wherein the temperature regulation means supply unit comprises: a first temperature regulation circuit wherein the temperature regulating means discharged from the outlet or outlets in the second end portion of said temperature regulation passages is directed to the refrigerator for cooling and then directed from the cooler to the entry or entries in the first end portion of said temperature regulation passages; a second temperature regulating circuit adapted to direct the liquid with high temperature discharged from the outlet or outlets in the second end portion of the passages that regulate the temperature directly to said inlet or inlets in the first end portion of the passages that regulate the temperature, and, a flow rate regulator adapted to regulate the temperature of the casting roller by controlling the liquid flow velocity distributions between said first and second temperature regulation circuits.

8. - The double roller continuous casting machine according to claim 7, wherein the temperature regulator is a cooling water tower.

9. - The double roller continuous casting machine according to claim 7 or claim 8, further comprising: a thermometer adapted to detect the temperature of the regulating medium of the temperature discharged from the outlet or outlets in the second end portion of the passages to regulate the temperature and produce an output signal corresponding to the detected temperature; a profile detector adapted to detect the profile of the thin strip and produce an output signal corresponding to the detected profile; a controller adapted to receive input and output signals from the thermometer and the profile detector and a target profile value of the thin band and to regulate the temperature of the temperature regulation means that is supplied to the passages that regulate the temperature and the regulating flow rate to produce the thin casting band of a desired profile.

10. - The double roll continuous casting machine according to claim 7 or claim 8, further comprising: a thermometer adapted to detect the temperature of the regulating medium of the high temperature of the outputs to the second end portion of the passages that regulate the temperature and produce an output signal corresponding to the detected temperature; a profile detector adapted to detect the profile of the thin casting band and to produce an output signal corresponding to the detected profile; a controller adapted to receive as inputs the output signals of the thermometer and the profile detector and receive an input corresponding to a target profile value of the thin band and to regulate the temperature of the temperature regulating means by the regulator of flow rate to produce thin casting band of a desired profile.

11. - The twin roll continuous casting machine of any one of the preceding claims, wherein the inner portions of the casting rolls are adapted to allow the regulation temperature of the medium to flow through the casting roll.

12. - A double roll continuous casting machine, comprising: a pair of laterally positioned casting rollers forming a contact point, adapted to support a casting tank of molten metal above the contact point, the casting rollers adapted to rotate in the opposite direction of the mold to form thin strip descending from the contact point; casting rolls having an inner portion and an outer circumferential portion; the outer circumferential portion having at least one set of circumferentially positioned passages in the adjacent casting cylinder of the casting surfaces adapted for the transport of liquid cooling liquid, and, the inner parts of the casting cylinders are adapted to allow a means of regulating the temperature to flow through the casting roller.

13. - The double roll continuous casting machine of claim 12, wherein the inner portion of the casting rollers further comprises a plurality of passages adapted to carry a temperature regulating means.

14. - The double roll continuous casting machine of claim 12, wherein the internal portion comprises a single passage adapted to carry a means adapted to cool the casting roller. SUMMARY In a continuous double-roller casting, the contour of the casting strip is controlled during casting by regulating the temperature of the medium that regulates the temperature circulated through the passage or temperature regulation passages in the casting rollers separated inwards from the castings. cooling passages in the circumferential portion adjacent to the casting surfaces. The temperature regulation passage or passages can be placed in the circumferential portion or in the inner portion of the casting rolls, or both.