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METHOD AND INSTALLATION OF ROLLING FOR THE AUSTENITIC ROLADO
OF THIN BANDS. FIELD OF THE INVENTION The invention relates to a process for the austenitic rolling or rolling of thin strips in hot strip trains, preferably fcSP apparatuses consisting of a rolling or rolling mill. The multiply equipped with an exit roller passage with installations. for the cooling of the rolling band and winding machines arranged subsequently for the winding of the bands. BACKGROUND OF THE INVENTION The hot rolling devices for the generation of strips are currently produced and operated in such a way that the shaping in the individual rolling equipment is performed austenitically. It is ensured that, the lamination temperature in the laminate equipment or individual rollers is above the GOS line of the iron-carbon diagram. Only after the last rolling indent, cooling to the lathe temperature with an initial transformation in the cooling section takes place. Depending on the degree of carbon content of the bands, in the above-described process, the final rolling temperature remains at about 890 to 930 ° C. The initial maintenance of the final rolling temperature is controlled by varying the speed of the last laminate, which has an influence on the natural cooling and on the heat supply through the rolling process. This is also applicable without problem for band thicknesses above the minimum strip thickness, which according to the type of the rolling mill, is in the magnitude of 1.3 mm. If it falls below this web thickness, then forced values of lamination speed higher than 12 m / s are reached, which in a free course in the exit roller process, can no longer be controlled behind the rolling mill, since that at this high speed, the heat band on the exit roll path, is no longer conducive without problems and can not be further worked with the furnace. In addition, the thermal problem is presented that the rolling process is characterized by non-constant band temperatures (deviations by means of the width of the band and the thickness of the band, more intense cooling of the previous band end compared to the beginning of the band). band, during the lamination in the finishing way). Development trends point in the direction of also manufacturing band thicknesses below 1.3 mm. This has led, among other things, to reduce the final rolling temperature in order to achieve controllable final rolling speeds. DE 195 38 341 A1 discloses a production apparatus for the manufacture of thin strips up to 1 mm thick, in which first an austenitic lamination of 5 to 15 mm is carried out and subsequently at temperatures above 850 ° a Ferritic laminate on a band thickness of approximately 1 mm. For this, the first equipment of the train or track of laminate band is formed as a reversion equipment to which, at least one lathe oven is provided before and afterwards, where between the lathe ovens and the following reversing equipment. , a controllable cooling device is provided. In the patent application (EP 97 120 406.0) it is proposed for the comparative measurement of the temperatures of the band - with which a heat band can be laminated with thicknesses below 1 mm - the disposition between the reserve equipment and the train for finishing the heat band, a compensating furnace, which, by means of a number of pick-up places for heatable bands in a compensatory manner, ensures a set heating time for each pre-band with a pre-band thickness, which , is a multiple of the rolling time in the finished train of the heat band. For this, a pre-band with a homogeneous temperature is generated, where the best possible conditions are created for the band lamination with a minimum thickness of the final band. In one application (Around-up of CSP thin slab 'Steel Times-Incorporation Iron and Steel, GB, Fuel and Metallurgical Journals LTD, London Vol. 226, No. 5, May 1, 1998, page 175, 176 , 178) is presented the structure of a CSP apparatus consisting of two lines of casting a train of laminate of multiple equipment and a stretch of cooled. The rolling mill is a winch or winch with two pins that are horizontal on a vertical rotation panel. The spigot directed towards the rolling mill serves to wind the strip coming out of the rolling mill. After the winding, turn the two pins 180 °. While the tang now deflected from the rolling mill winds the web into a coil, a free tang for the winding is presented for the next band without loss of time. In order to austenitically laminate thin strips on CSP devices, extremely high travel speeds (up to approximately 20 m / s) are required. An assured transport of the rolled strip on the exit roller path is only possible with a maximum of 12 m / s precisely insofar as the tip of the band that leaves the last equipment, is captured by the winch under the floor and rolled up. Only later, can the train accelerate to higher output speeds. In a lamination strategy of this type, different rolling conditions and the great distance between the last equipment and the sub-floor lathe lead to the principle of the laminated strip not exhibiting the desired mechanical qualities of the material. These are only achieved if they have already been rolled approximately 130 m, which reduces the performance of the train. SUMMARY OF THE INVENTION Starting from the known state of the art, it is sought to present a known procedure with which the highest final rolling speed or the exit velocity that occurs during the generation of thin strips below 1.2 mm, is controllable with means simple, so that the disadvantages that occur in the known method and apparatus can be largely avoided, such as low efficiency or high expenditure on appliances, together with additional operating costs, by additional heating or cooling. The established task is solved by means of a hot band train preferably a CSP apparatus that presents the characteristic features of the claim. Advantageous embodiments of the invention are presented in the dependent claims. For the lamination of extremely thin strips, according to the invention, a winding or winding machine is placed, for example a rotating lathe behind the last rolling equipment or rollers and also before the exit roll step in the rolling line . The first band, now reels with its high output speed on the first pin of the rotor lathe, in a first coil, then the spindles of the rotary lathe are deflected 180 °. Now, while the first band rolls up again with the slow transport speed (maximum 12.5 m / s) and is transported by means of the roll of exit rollers towards the subsoil lathe, on the second spindle of the rotary lathe the following The belt is wound with a high output speed in a second coil. Then the spindles of the rotary winch are rotated 180 ° and the next band can now be wound. In this way the winding and unwinding is performed continuously. In this way the belt will be wound directly after its exit from the last rolling machine with its high final rolling speed or output speed, but then it will immediately re-unroll - and precisely now with the slowest transport speed - there is the misaligned rolling train of the exit roller passage with which, a final rolling speed or high output speed and low transport speeds are possible simultaneously and are no longer caused by disadvantages or problems due to the application of a high output speed, even when the output speed is not too high.; 12.5 m / s and for example have a magnitude of 20 m / s and the transport speed is clearly slower with a speed < 12.5 m / s. No influence is exerted on the ingots or the successive coils, by the winding and unwinding measures, since according to the invention, during the unwinding, the next band is already being wound up. Since in winding due to the higher speed it is more quickly finished than the simultaneous unrolling of the previous band, then the rotary winch is first turned 180 ° when the unwinding process has been completed. Then in the wound coil A small pause is produced which advantageously leads to a temperature compensation of the different zones of the band. Another advantage of the invention is that after the winding and unwinding carried out, the ends of the band are exchanged with each other, and now the original end of the band, is led first to the passage of the output roller for cooling. A rolling apparatus for carrying out the process, according to the invention, has a winding machine, for example a rotating lathe which can be rotated to be placed directly before the last rolling equipment and after the running roller step the rolling line and which is constructed with two winding pins offset 180 °, and which are displaceable 180 °. DESCRIPTION OF THE DRAWINGS Other advantages, features and characteristics of the invention are described in more detail with reference to the embodiment shown schematically in the drawing figures. Figure 1 shows a cut of a rolling mill hitherto usual, with a rotating lathe corresponding to the invention. Figure 2 shows a diagram of the different speeds of the band. Figure 3 shows a plan view with a section of the rolling mill according to Figure 1. Figure 4 shows a plan view in a section of a rolling mill with another embodiment of the invention.
DESCRIPTION OF THE INVENTION Figure 1 shows a continuous or string casting apparatus 1 (it is a two-string apparatus) which includes shears 2, a compensation furnace 3, another shear 4, as well as a rolling mill 5 of multiple teams. Behind the rolling mill 5, there is the exit roller passage 10, with the installations 6 for cooling, and then a deflection roller 9 with a subsequent sub-floor winch 7 for the winding of the finished strip. According to the invention, a rotating lathe 8 with two winding pins 8 ', 8' is inserted into the rolling line immediately behind or after the last rolling unit of the rolling mill 5. ' The band from the rolling equipment is driven as it leaves the rolling line by means of the first deviation equipment 8 ', in that rotating lathe 8 on the pin 8' as a winding band 11. From a second spike 8" which is displaced 180 ° with respect to the first shank 8 ', the web is fed back as unrolling strip 12, by means of the second deflection roller 9'1, back to the rolling line towards the outlet roller passage 10. The two winding pins 8 ', 8'1 of the rotary winch 8 are constructed so as to be driven independently of one another, so that different speeds of winding and unwinding according to the characteristics of the invention are possible. In figure 2, the band speeds prevailing in the hot band train are presented schematically, in accordance with Figure 1. With the VLINGOTE speed, or VB, the slender ingots are cast and taken to the compensating furnace 3 and to the rolling mill 5. The output speed VLAM1NAD0, or VB with the thin strip 11 and finally laminated to the rotary lathe 8, where it rolls From this rotary lathe 8, the front band is then forced as unwinding band 12 with the speed VTRANSPORTE, or VT towards the sub-floor lathe 7 by means of the exit roll 10. In FIG. 3, a partial cut-off is shown. Figure 1 in a schematic plan view. The web that emerges from the rolling equipment 5 with the winding speed V - the winding band 11 is wound on the pin 8 'of the rotary winch 8. Simultaneously, it is unwound from the unwinding band 12 from the second pin 8'. 'arranged behind the spigot 8' in the transport direction and which belongs to the rotary lathe 8 with the transport speed Vt.
As soon as the unwinding band 12 has completely abandoned the pin 8"- due to the higher winding speed V, the winding band 11 is already fully wound up - a turn of the pins 8 and 8 'is made around of the pivot point 15 of 180 °, with which the two pins 8 'and 8"exchange their positions. The unwinding pin now emptied 81 'remains in the position of the old winding pin 81 and the full winding pin 8' remains in the position of the previous unwinding pin 8 '' With this, in this change of positions, the winding and unwinding can be performed on the pins 8 'and 8", the two pins 8' and 8" being displaced in their arrangement 180 °, so that each pin 8 ', 8"after a change of position is in the same direction as the previous spike. The rotation or deviation of the pins 8 ', 8'1 for the change of position can be carried out in the desired position, corresponding to the double arrow 14, but also in only one direction, for example only in the direction of rotation of the hands of a clock. Therefore, in the lamination of thicker bands in which a lower output speed V is used, the measures of the invention can be dispensed with, and the band can be directly driven to cooling, the lathe 8 being arranged correspondingly to the arrow direction 13 laterally in the rolling line and being insertable and removable thereto. The entrance and exit - is not represented in the figures of the drawings - but is also realizable from below to the line of laminate. In figure 4, another possible embodiment of the invention is shown in plan view. In this example of Figure 4, there are not the two pins 8 ', 8", placed in the transport direction one after the other as in Figure 3, but are arranged next to each other. The change of position here also takes place by a rotation of the two pins 8 ', 8"of 180 ° in the direction of the arrow 14, but now laterally around the pivot point 16 arranged laterally next to the winding band 11. and the unwinding band 12. The following are presented in a table, as an example, the action times in the manufacture of a thin strip:
Ingot casting Unwinding laminate / 50 X 50 mm 0.8 mm winding cooling. VB = 5.5 mm Vw = 20 m / s Vt = 12.5 m / s 9 min / ingot winding 2.6 min Tilting = 0.3 min (2-string device) Pause 1.6 min Unwinding Tipping 0.3 min = 4.2 min Next ingot Next coil Next coil = 4.5 min = 4.5 min. = 4.5 min.
From the table it can be concluded that by the measures of the invention, only a deviation of the time corresponding to a next ingot is reached, in which the laminated strip is guided to cooling. The invention is not limited to the example shown and indicated, but the construction can be adjusted correspondingly to an existing hot band train or that is conceived as new with the given relations, if, the basic thought of the invention, which is the band, is maintained. thin directly after the rolling with its high output speed, roll it up and re-unwind it with a correspondingly lower speed.