MXPA00004549A - Method to control the axial position of slabs emerging from continuous casting and relative device - Google Patents

Abstract

Method to control the axial position of slabs emerging from the continuous casting machine, the method providing to control the axial position of the slab (24) in correspondence with the inlet to the first rolling stand and to act in feedback on means to modify the correct position of the axis (32) of the slab (24) in a position located between the first rolling stand and the foot rolls (26) of the ingot mold (13) from which the slab (24) emerges and wherein, in order to intervene upstream of the furnace (15) cooling systems (28) are employed which act on the sides of the slab (24), the method also using alignment means operating inside the furnace (15) and inducing a controlled lateral displacement governed by the control of the axial position of the slab (24). Device to control the axial position of slabs emerging from the continuous casting machine comprising cooling means cooperating with the sides of the slab (24) extracted from the ingot mold (13) and alignment means operating inside the heating and temperature maintenance furnace (15) and inducing a lateral displacement of the slab (24), the means (28) and the alignment means being governed by means (31, 36) to control the position of the axis (32) of the slab (24).

Description

METHOD FOR CONTROLLING THE AXIAL POSITION OF SLABS ARISING FROM CONTINUOUS EMPTYING, AND RELATED DEVICE FIELD OF THE INVENTION This invention relates to a method for controlling the axial position of slabs arising from the continuous casting, and the related device, as stipulated in the respective main claims. The invention is applied in rolling mills having the rolling mill located in line with the continuous casting machine, and is used to obviate the problems of the slab arising from the emptying machine with its misaligned axis with respect to the axis of the first rolling station. The invention is used both when the slab is less than 100-120 millimeters thick, and is cut to the size in segments, and also when the slab is obtained with a total casting of molten metal, and also when the slab is worked with continuity between the emptying machine and the rolling mill.

BACKGROUND OF THE INVENTION One of the main problems that laminator operators complain about is the way of controlling the axial position of the slab with respect to the axis of the first laminating station located downstream of the heating furnace. It is well known that the slab, as it emerges from the continuous casting machine, because it must be subjected to the processes of extraction, pre-rolling, and straightening, rarely remains correctly aligned with the feed axis; This causes considerable problems when the slab enters the rolling station and during the rolling steps. Moreover, as it travels inside tunnel kilns, either the heating furnace or the temperature holding furnace, the slab may be subject to lateral displacements that send it out of line. If the slab arrives poorly aligned with respect to the axis of the first station, rolling becomes difficult, particularly when thin diameters are being rolled. In fact, in order to compensate for this misalignment after the slab has entered the station, and to ensure that it enters the downstream station in a correct manner, it is necessary to act on the horizontal positioning of the first station, which which can have negative effects on the symmetry of the profile in the cross section of the slab itself. Although this does not create particular problems when the partially rolled product has a greater thickness, for example, greater than 2 millimeters, in the case of thinner products there are considerable problems of quality, because it becomes extremely difficult, if not that impossible, recover the difference in thickness between one side and the other, when the product is 0.6-0.8 millimeters thick. In the case of thin products, the transversal sliding of the material is very difficult to obtain, and in any case, it causes errors in the plane, which are derived from a differentiated stretch of the material. In order to solve these problems, at least partially, the solutions known in the art employ the action, either individually or in combination, of lateral guides, of the descaling assembly or of the rollers or assemblies to finish the edges, which are configured between the exit of the heating furnace and the entrance to the station, in order to obtain the progressive axial alignment of the slab and the rolling axis. These solutions have shown that they are only partially effective, for a variety of reasons. First of all, there is a technological requirement where the entrance to the station can not be too far from the exit of the kiln (the typical maximum value is around 14 to 20 meters), to prevent excessive cooling of the slab to less than the optimum lamination temperature. For this reason, it is necessary to obtain a greater displacement of the slab per unit length of the plant, in order to obtain the desired alignment in correspondence with the entrance to the station. Guidance systems are known in this field; however, they are not able to obtain these displacement values, and therefore, are not able to achieve the desired alignment in the small space available between the furnace and the stations, which is imposed by technological limitations. Moreover, the lateral guides, as known in the art, occupy approximately 10 meters in length of the segment between the furnace and the station, and define a transit width that is greater than the width of the slab, on both sides, by when minus 25 millimeters per side, up to as much as 50 millimeters per side. Therefore, the alignment of the slab is imprecise by values of + 25-50 millimeters. Moreover, the rollers that refine the edges, or the edgers, can not act on the edges of the slab by more than approximately 10 millimeters per side. All these factors make it impossible to center the slab, if the slab arrives poorly aligned with respect to the rolling axis beyond a minimum value that can be compensated, and that can be estimated in the region of + 10 millimeters.

There is also the additional problem with respect to the transport rollers inside the heating furnace. In order to withstand extremely high temperatures of up to 1, 100 ° C-1, 200 ° C inside the furnace, these rollers are structured with cooled rolls that support discs made of refractory material that is mechanically very delicate, so that even a slight transverse displacement of the advancing slab causes considerable damage, and puts the disks out of action very quickly. Therefore, it is highly undesirable to make the slab move laterally when it is inside the oven. Japanese Patent Number JP-A-62235429 teaches to provide nozzles configured above and below the passing laminate material, which supply a jet of gas in the direction opposite to the feed direction of the laminate. The nozzles are configured in a zigzag conformation, and exert a mechanical displacement action on the laminate if it is not centered with respect to the related feed element. This device makes it possible to obtain only limited adjustments in the position of the laminated material, and moreover, it can cause unacceptable modifications in the surface temperature conditions thereof. European Patent Number EP-A-416356 discloses an alignment station for rolled products configured between the stretch-straightening assembly acting on the rolled material arising from the continuous vortex, and the cutters that cut the laminated material into segments, which then they are sent to the temperature equalization oven. The alignment station consists of a support roller, placed below the plane on which the laminated material is fed, with bearings that are connected to a related vertical piston suitable for tilting the roller to one side or the other, to correct any possible lateral displacement of the laminated material. In an alternative way, the alignment station comprises at least one burner, or at least one spray nozzle, which cooperates with at least one edge of the laminate, in order to align the laminate material, either by exploiting the expansion caused by the heating, or exploiting the shrinkage caused by cooling. The fact that the alignment station is placed upstream of the cutter assembly and the furnace creates the problem that, precisely during the cutting cycle or during the heat treatment in the furnace, the segment of rolled material reaches be misaligned, and arrives in correspondence with the first stations of the rolling mill in an off-center condition. Moreover, the inclusion of a single alignment roller can make it impossible to correct the bad alignments of the laminated material of a certain entity, because the lowering or raising of one side of the roller with respect to the other is limited by the overall height of the feed plane . Additionally, European Patent Number EP'356 does not mention systems to control the position of the slab with respect to the axis of the rolling stations, nor feedback systems that regulate the alignment elements and the condition of their operation in the event that there are bad alignments downstream. The present applicant has designed and tested this invention to overcome these drawbacks that cause serious operational and technological problems, and quality problems, in the rolling of flat products, particularly thin flat products of less than 2 millimeters and down to 0.8-0.5 millimeters.

COMPENDIUM OF THE INVENTION The invention is stipulated and characterized in the respective main claims, while the dependent claims describe other features of the main embodiment. The purpose of the invention is to axially center and align the slab as it emerges from the continuous dump machine, in such a way that, when it arrives at the entrance of the first stations, be they stations of raw lamination, pre-finishing, or finishing, it is perfectly aligned with the axis of these stations. The invention obtains the aforementioned result without causing any deterioration on the surface or the edges of the slab, without any risk of damaging the discs of the transport rollers inside the furnace, without substantial modifications to the structure of the lateral guides, the bumpers , or the descaling assembly located at the exit of the oven, or the channels used to guide the laminated material, which are located at the entrance to the stations. The invention allows to reduce the extension of the lateral guides, or even eliminate them, with the consequent advantages in terms of deployment; and therefore, the slabs are warmer when they enter the rolling stations, and the length of the plant is reduced. The invention uses the individual or combined action of a plurality of assemblies and devices located between the exit of the ingot mold, in the region of the leg rolls containing and extracting the slab, and the entrance of the first rolling station. According to the invention, the slab emerging from the ingot mold is subjected to a controlled cooling process that cooperates with the sides of the slab, in order to obtain a desired lateral displacement achieved by the different thermal expansion of the two sides of the slab. In other words, if it is discovered that the slab comes out of the continuous emptying machine already ill-aligned with respect to the nominal rolling axis, the secondary cooling assemblies are caused to act in a controlled manner, to achieve a differentiated thermal expansion on the two sides, in order to compensate, at least partially, the extent of this misalignment. According to a variant, downstream of the secondary cooling assemblies and / or in an intermediate position between them, there are elements for measuring and controlling the axial position. The measuring and control elements verify, either continuously or periodically, that the misalignment is corrected, and condition the secondary cooling assemblies in feedback, in order to vary the intensity and the cooling action of a desired way.

According to another variant, in the case that the measuring and control elements verify that there is an excessive displacement that can no longer be compensated downstream, they order the cutting elements to be activated, which intervene and form short slabs that they can be easily handled inside the oven, even when they are progressively misaligned. According to the invention, the rollers inside the heating furnace are driven independently, individually or in groups, in such a way that the progressive realignment of the advancing slab is determined. In one embodiment, the rollers are configured at an angle with respect to the nominal horizontal plane on which the slab is, and the even rollers and the nons rollers are driven in an autonomous and separate manner. The motors of the nones and pairs rollers are regulated, according to a variant, by means of an element to control the axial position of the slab, which orders the rollers to be activated according to the degree of misalignment found, possibly correcting the work parameters in the feedback. The different and controlled rotation speed of the nons and even rollers inside the furnace, together with its angled position with respect to the plane of the slab, causes a progressive realignment of the slab with respect to the rolling axis of the station located downstream, without causing any deterioration of the slab itself, and without intervening on the guidance devices located between the furnace and the station. In another embodiment of the invention, the furnace rollers, either individually or in groups, are associated with elements that regulate the inclination of the rollers on the horizontal plane with respect to the nominal position corresponding to the orthogonal to the feed axis of the furnace. laminated material. These inclination adjustment elements are governed by elements that control the axial position of the slab at the exit of the kiln, and intervene by varying the inclination of the rollers, on one side and / or the other of them, and by defined angles, until the axial position of the rolled material with respect to the axis of the first rolling stations has been restored. In a further embodiment of the invention, there is a wheelbarrow used as an element for transporting the slab, with an insulated cover and heating elements, operating at least partially as a heating and / or temperature holding furnace. The truck can be moved sideways in a controlled manner. In this mode, there is a device to control and measure the axial position of the slab, located at the exit of the truck, which verifies the alignment with respect to the axis of the first station, and orders the lateral displacement of the truck, such so that the slab is progressively brought up to align with the rolling axis. These verifications, and the consequent lateral displacements, can take place, either in a continuous or periodic way, at previously determined intervals. According to a variant, the device for controlling and measuring the axial position is included, or is also included, inside the truck. According to another variant, the two support beams are mounted along the furnace, on which the rollers extend inside the furnace, and are subdivided into several coherent segments that are equipped with lateral movement, one independently of the other. These independent lateral movements, ordered by the elements to control and measure the axial position of the slab, make it possible to correct any possible misalignment of the slab, and reduce its misalignment with respect to the nominal rolling axis. This mode is particularly indicated for long slabs, up to 200-300 meters long, that is, slabs that occupy substantially the entire length of the tunnel kiln. According to an additional variant, the furnace rollers are associated, on the opposite side with respect to the motor side, with a support that can be raised and lowered to modify the lateral position of the slab running through the furnace. The rollers, according to a further variant, are in groups, and are raised / lowered in a coordinated and progressive manner by means of actuators associated with the monitoring of any misalignment between the axis of the slab and the rolling axis. According to another embodiment, the respective discs of the rollers are alternately configured between one roller and the subsequent roller, that is, the discs are grouped together on one half of the roller, and on the other half of the next roller. This configuration gives a wavy progress of the slab inside the furnace, which regulates the position and substantially aligns the slab with the rolling axis. According to another embodiment, outside the furnace, in a lateral position thereto, are the cone-shaped rollers distributed along the length of the furnace and on both sides thereof, up to a desired number, in intermediate positions between the furnaces. usual transport rollers. One and / or the other of the conical rollers, are inserted inside the furnace when a bad alignment of the slab is monitored, so that a controlled axial displacement is determined due to the conical shape of the rollers. When the tapered rollers are inserted, the slab is lifted and the contact with the usual transport rollers is loosened, and consequently, it can be moved laterally in the desired direction. According to a variant, two conical rollers configured coaxially are inserted on one side of the furnace and the other, inside the furnace, to completely raise the slab, and move it to the sides in the desired direction. According to another variant, the conical rollers have a raised edge on the base, which is used as an element to physically move the slab. According to a further variant, the tapered rollers with the raised edge are constantly kept inside the furnace on their two sides, to function as an element to constantly control the axial position of the slab, and to limit lateral displacement.

BRIEF DESCRIPTION OF THE DRAWINGS The attached Figures are given as a non-restrictive example, and show some preferred embodiments of the invention as follows: Figure 1 is a diagram of a rolling line, seen from the side, directly connected to the machine continuous emptying to which the invention is applied. Figure 2 is a diagram of a segment of the line shown in Figure 1, as seen from above. Figure 3 shows a first embodiment of the invention applied to the outlet of the continuous emptying machine. Figure 4 shows another embodiment of the invention as applied to the heating furnace located upstream of the first rolling station. Figures 5a and 5b show, respectively, from the front and from the top, another embodiment of the invention. Figures 6 and 7a show additional embodiments of the invention. Figure 7b shows a partial front view of the Figure 7a. Figure 8 shows a cross section of another embodiment of the invention. Figures 9a and 9b show two working configurations of the embodiment shown in Figure 8. Figure 10 shows a further embodiment of the invention. Figure 11 shows a working configuration of the embodiment shown in Figure 10. Figure 12 shows a variant of Figure 11.

Figure 13 shows a variant of the previous modalities. Figure 14 shows a further embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITY The rolling line 10 shown diagrammatically in Figure 1, comprises a rolling mill 19 configured in line with a continuous casting machine 11 which includes a mold of ingots 13, and an extraction and straightening assembly that includes rollers 12. Downstream of assembly 12, there is a cutter for cutting to size 14, and a heating furnace and / or temperature maintenance 15, which feeds the slabs at the temperature to a rolling mill 16, in this case with two stations 17, which may be a raw rolling mill, or a pre-finished mill, as the case may be. Between the train 16 and the finishing train 19, in this case, there is a system for equalizing and restoring the temperature 18, while downstream of the finishing train 19, there is the winding assembly 21, for winding the strip produced. In this case, between the heating furnace 15 and the train 16, there are the conventional systems that include side guides 20, a de-crusher assembly 22, and an assembly for finishing the edges 23, of the type including rollers.

According to the invention, the rolling line 10 includes elements for aligning the axial position of the slab 24 as it arises from the continuous dump machine 11 to the rolling axis 25 of the rolling stations 17, and particularly to the axis 25 of the first station 17 of the train 16. Figure 3 shows a first embodiment of the invention. In this case, the slab 24 arising from the ingot mold 13, and from the leg rolls 26, and coupled with the rollers 27 of the extraction and straightening assembly 12, is made to cooperate with the cooling element 28, which comprises supply nozzles 29 cooperating with the sides of the slab 24. The supply of the cooling fluid by the supply nozzles 29 is regulated by the command units 30, which receive position signals from the detectors 31 configured in cooperation with the sides of slab 24 that is being extracted. The detectors 31 are previously set to detect the position of the axis 32 of the slab 24, and to verify any difference in axial position with respect to the rolling axis 25. There may also be a detector 36 suitable for detecting the position of the edges, which does not need to be replaced, because the width of the slab 24 varies. ~ > When a bad alignment is detected, there is a variation in the supply of the cooling fluid, possibly differentiated on the two sides of the slab, by means of a controlled activation of the nozzles 29. By means of this control, which is carried out directly during the secondary cooling step, the shaft 32 of the slab 24 can be aligned with the rolling axis, laterally displacing the slab 24 itself, due to the thermal expansion. In the event that the displacement is excessive, and can not be compensated downstream, the invention provides to activate the cutter 14 as an emergency cutter, in order to obtain short slabs of such size that the front edges do not damage the internal refractory surfaces of the furnace 15, even when the slab is misaligned. In the embodiment shown in Figure 4, the temperature heating and maintenance furnace 15 consists of a cart 34, which can be moved sideways on the rails 35, inside of which the support rollers identified by the carriers are mounted. axes 37. The truck 34 cooperates with an isolated bell 38 associated with the heating element and the intake element, which are not shown here. The truck 34 can receive the slabs 24 from one or more emptying lines, and can be used to feed a single rolling mill with slabs 24 arriving from different emptying lines, or from cold slab warehouses, or from products special According to the invention, the lateral movement of the truck 34 is used to axially align the slabs 24 that are misaligned with respect to the rolling axis 25. To be more exact, the axial position of the slabs 24 is monitored by the element. detector 36 configured stationary at the outlet of the oven 15 and upstream of the train 16, or inside the truck 34 itself, which is connected in feedback with a control unit 30. The control unit 30, according to the position, signals the arrival from the detector element 36, activates the actuator 33, which laterally displaces the truck 34, progressively aligning the axis 32 of the slab 24 with the rolling axis 25. In the case shown here, the truck 34, with an axis 34a, has been displaced by a value? to align the rolling axis 25 with the axis 32 of the slab 24, having entered the slab 24 to the truck 24 ill aligned with respect to the axis 25. Once the slab 24 has emerged, the truck 34 can be carried back progressively to its original position, that is, with its axis 34a aligned with the rolling axis 25. In the embodiment shown in Figures 5a and 5b, the support rollers 39 inside the oven 15 are associated, individually or in groups, with the piston element 57, respectively 57a on one side, and 57b on the opposite side, suitable for displacing the inclination of the rollers 39 with respect to the horizontal plane on which these rollers 39 remain. To be more exact, the supporting rollers 39, which have a nominal position "0", where their axis 37 is substantially orthogonal to the feed axis of the slab 24, are inclined on the horizontal plane by an angle a, in one direction or in the other, by means of the Piston 57a or 57b. The entity of the inclination, and the direction of inclination, are determined in accordance with the signals supplied by the detector element 36, which measures the entity of the misalignment of the slab 24 at the outlet of the oven 15, and sends the signals to the control unit 30. The control unit 30 processes the data and sends command signals to the piston element 57a and 57b, to re-establish the correct alignment of the slab 24 with respect to the axis of the first rolling stations. The rollers 39 are individually assembled on trucks 58 equipped with wheels 59, and each can be equipped with its own piston element 57. In the embodiment shown in Figure 5b, several rollers 39 are connected to each other by means of respective connecting elements 60, which allows the rollers 39 to be driven in a simultaneous manner; this can affect groups of rollers 39, or even all of the rollers 39 inside the oven 15. In the additional embodiment shown in Figure 6, the support rollers 39 inside the oven 15 can be moved laterally in a controlled manner , parallel to its axis 37, with respect to the stationary structure 38 of the furnace , which does not move. In a first embodiment, all rollers 39 can be displaced laterally, independently of one another. According to a variant, the rollers 39 can be moved in groups, for example two by two or three by three. The lateral displacement can be commanded by position detectors of the same type as the detectors 36 shown in Figure 4; this allows the slab 24 to be displaced laterally when it rests on the discs 40, without the slab 24 sliding laterally on the discs 40, that is, without damaging them or wearing them out.

The position sensors 36, which are not shown in Figure 5, are connected in feedback with the displacement actuators 41, which act on the sliders 42 on which the bench supports 43 rest; the bank supports 43 support the rotational bearings 44 on the rollers 39. The rollers 39 are rotated by a motor 47. The sliders 42 slide on guides 45 made on the planes of displacement 46. Once the rear end of the slab 24 has left each individual roller 39 or group of rollers 39, the rollers are realigned to receive a new slab 24. In the embodiment shown in Figure 7a, the axial alignment of the slab 24 with respect to the axis of Lamination 25 is obtained by modulating the rotation speed of the rollers 39 in a differentiated manner. In this specific case, the rollers 39 are angled with respect to the plane on which the slab 24 rests. The non-uniform rollers 39a are commanded by a command unit, while the even rollers 39b are commanded by their own unit, of autonomous command . The command units are connected in feedback with the detectors 36 of the type shown in Figure 4, suitable for detecting any axial misalignment between the axis of the slab 32 and the rolling axis 25. If any misalignment is detected, and agreement with the degree of misalignment, the rollers 39a and 39b are commanded to obtain the controlled lateral displacement of the slab 24, acting on its differentiated and variable speeds. By tilting the rollers 39 with respect to the plane of the slab 24, the contact points of the relative discs 40 rotate at different speeds on one side of the slab 24 and the other (Figure 7b), and consequently, the slab 24 can be moved laterally in a controlled manner. According to a variant, each roller 39 can be controlled in an individual manner and independent of the other rollers 39. In the embodiment shown in Figure 8, the rollers 39 are supported on the side, on the side of the motor, by a stationary support 48, while on the opposite side, they are supported by a support 49 that can move vertically. In the modality shown here, the support 49 consists of a plane inclined towards the furnace 15, and which cooperates with an actuator 50 that displaces the support 49 on the horizontal plane. When the actuator 50 is activated in one direction or in the other, there is a correlated rising or falling of the movable support 49, and consequently, one side of the related roller 39 is accordingly tilted in one direction or in the other. Figures 9a and 9b show two possible conditions that may occur: - in Figure 9a, where the slab 24 tends to misalign to the right with respect to the rolling axis 25, the movable supports 49 are raised to tilt the rollers 39 down and to the left; in Figure 9b, where the slab 24 tends to misalign to the left with respect to the rolling axis 25, the movable supports 49 are lowered to tilt the rollers 39 down and to the right. The actuator 50 is connected, conveniently by means of a feedback control system, to a command unit that receives signals related to the misalignment of the slab 24 from the detectors 36 configured inside the oven 15, and correlates the degree and direction of movement of movable supports 49 with the degree of misalignment. In the embodiment shown in Figure 10, in a lateral position outside the oven 15, conveniently on both sides of the oven 15, are the tapered rollers 51, cooled and mounted as cantilevers on a related support 52.; its axis is parallel to the axis 37 of the usual feeder rollers 39. The support 52 is associated with a slider 53, which slides on a guide 54, to bring the roller 51 from a standing position outside the oven 15, to a position active, where it is inserted inside the oven 15; as it enters into cooperation with the slab 24, it lifts the slab 24 at least on one side from the usual feeder rollers 39, and makes it move to the sides in the desired manner. In the event that the lateral displacement caused only by the conical shape of the working surface of the roller 51 is not sufficient, or in the case of difficulties to be reached, a raised edge 55 which cooperates with the base of the roller 51 in contact with one edge 24a of the slab 24, to physically move the slab 24. The conical rollers 51 can be configured alternately and out of phase, on one side of the oven 15 and the other, along the entire length of the oven 15 itself, for example, every 4 to 6 of the usual rollers 39. In accordance with the variant shown in Figure 12, the tapered rollers 51 are in pairs, axially configured on one side of the furnace 15 and the other, and are actuated from a simultaneously to lift the slab 24 from the support plane 56 defined by the usual rollers 39, and to move it laterally, in one direction or in the other, according to the misalignment? detected between the rolling axis 25 and the axis 32 of the slab 24, by introducing the conical rollers 51 inside the furnace 15, to a greater or lesser degree. Once the slab 24 has been axially repositioned, the tapered rollers 51 are returned to their standby position outside the oven 15. According to the variant shown in Figure 13, which is valid for all the embodiments described above in present, the tapered rollers 51 are constantly kept inside the furnace 15, configured on both sides thereof, and function as elements to control and limit the maximum difference between the axial position of the slab 24 and the rolling axis 25. The rollers conical 51, configured coaxially in pairs in an intermediate position, for example, every four conventional rollers 39, with their edges raised 55, define the position of the maximum lateral displacement of the slab 24; at the same time, with their inclined work planes, they act as elements to control in a constant and continuous way the axial position of the slab 24. According to the additional variant shown in Figure 14, the discs 40 mounted on the rollers 39 they are formed in groups on one half of a roller 39, and on the other half of the roller 39 immediately thereafter. This configuration of the disks 40, together with the individual control of the rotational speed of the individual rollers 39, makes it possible to give an undulated development to the slab 24 as it passes through the oven 15, to control its lateral position, and to correct any possible misalignment of the slab 24 with respect to the rolling axis 32.

Claims (31)

1. A method for controlling the axial position of slabs arising from the continuous dump machine applied to the rolling lines, which comprises at least one continuous dump machine (11) with at least one ingot mold (13), an assembly extraction and straightening (12), a cutting element (14), a heating and / or maintenance furnace (15), a raw or pre-finished rolling mill (16), and a finishing train (15) 19) defining a rolling axis (25), this furnace (15) comprising a plurality of transport rollers (39) that define a substantially horizontal support and transport plane for the slabs, being included between the output of the heating furnace and / or maintenance of the temperature (15) and the entry of the raw rolling mill (16), lateral guides (20), and at least one de-scaling assembly (22), using the method to laterally align the axis (32) of the slab (24) that south ge from the continuous dump machine (11), with the rolling axis (25) of a first station of the raw rolling mill or pre-finished (16), or of a first station of the finishing train (19), the method being characterized because it has to continuously control the position of the slab (24) with respect to the rolling axis (25) by means of the detector element (36) configured at least upstream of the entrance of the first rolling station, and to act in feedback on the alignment element that operates inside the heating furnace and / or maintaining the temperature (15), and cooperating with the transport rollers (39), this alignment element being able to modify the position of the axis (32), inducing a controlled lateral displacement of the slab (24) in transit on the support and transport plane functionally correlated with the control of the axial position of the slab (24).

The method as in claim 1, characterized in that the alignment element operates inside the heating furnace and maintains the temperature (15), and laterally displaces the slab (24) by means of a controlled inclination on the horizontal plane of at least some of the transport rollers (39) located inside the furnace (15), with the entity of the inclination angle "a" and the inclination direction, a function of the misalignment entity of the slab (24) with with respect to the rolling axis (25), as detected by said element (36).

The method as in claim 1, characterized in that the alignment element that operates inside the heating and temperature maintenance oven (15), laterally displaces the slab (24) by means of a controlled lateral displacement of a truck ( 34), which supports the transport rollers (39), and which constitutes at least part of the heating and temperature maintenance furnace (15), this lateral displacement being governed by this element (36) to control the axial position of the slab (24).

4. The method as in claim 1, characterized in that the alignment element that operates inside the heating and temperature maintenance oven (15) laterally displaces the slab (24) by means of a controlled lateral displacement, either individually or in groups, of the transport rollers (39) inside the heating and temperature maintenance oven (15), this displacement being governed by the element (36) to control the axial position of the slab (24).

The method as in claim 1, characterized in that the alignment element that operates inside the heating and temperature maintenance oven (15), laterally displaces the slab (24) by means of an independent control, either individually or in groups, the speed of rotation of the transport rollers (39) inside the heating furnace and maintenance temperature (15), the transport rollers (39) being inclined with respect to the support and transport plane on which the slab (24) remains, the independent control being governed by the element (36) to control the axial position of the slab (24) .

The method as in claim 1, characterized in that the alignment element that operates inside the heating and temperature maintenance oven (15), laterally displaces the slab (24) by means of the controlled lifting of one side of the rollers. of transport (39) placed inside the furnace of heating and maintenance of the temperature (15), this controlled lifting being governed by the element (36) to control the axial position of the slab (24).

The method as in claim 1, characterized in that the alignment element that operates inside the heating and temperature maintenance oven (15) laterally displaces the slab (24) by means of the controlled insertion inside the oven (15). ), on one side or the other, of at least one conical roller (51) with a working plane inclined in the direction of the oven (15), and configured in the space between the transport rollers (39), the insert being controlled controlled by the element (36) to control the axial position of the slab (24).

The method as in claim 7, characterized in that the conical rollers (51) are constantly kept inside the furnace (15), on the side of the slab (24), on one side and the other, with the function of controlling the position and limit the maximum lateral displacement of the slab (24).

The method as in claim 1, wherein the transport rollers (39) cooperate with a plurality of disks (40) configured coaxially over at least part of their periphery, characterized in that the alignment element that operates inside the furnace of heating and maintaining the temperature (15), laterally displaces the slab (24) by means of configuring the alternate disks (40) on one half of a roller (39), and on the other half of the subsequent roller (39), and by independent control of the rotation speed of the rollers (39).

The method as in claim 1, characterized in that it provides for continuously controlling the axial position of the slab (24) at least upstream of the entrance of the first rolling station, and acting in feedback on differentiated cooling systems (28) confiscated downstream of the mold of ingots (13), and in the vicinity of the two sides of the slab (24), these systems being able to create on these sides of the slab (24), a differentiated thermal expansion.

The method as in claim 10, characterized in that, if the thermal expansion causes too great an axial displacement that can not be compensated downstream, it arranges to cut the slab (24) by means of the cutting element (14), as a function emergency, to obtain short slabs.

12. A device for controlling the axial position of slabs arising from a continuous cast applied in rolling lines, which comprises at least one continuous dump machine (11) with at least one ingot mold (13), an assembly of extraction and straightening (12), a cutting element (14), a heating and / or maintenance furnace (15) comprising a plurality of transport rollers (39) configured parallel to each other, with their axis substantially orthogonal to the feed axis of the slab (24), and defining a substantially horizontal support and transport plane for the slab, a raw or pre-finished rolling mill (16), and a finishing train (19) defining a rolling axis (25), including between the output of the heating furnace and / or temperature maintenance (15) and the input of the raw rolling mill or pre-finished (16), side guides (20), and at least an assembly d scrubber (22), the device being characterized in that it comprises an element (36) for controlling the axial position of the slab (24) with respect to the rolling axis (25), this element (36) being configured at least upstream of a first station of the rolling mill raw or pre-finished (16), or finishing train (19), and alignment elements that operate inside the heating and / or maintenance furnace (15), and cooperate with the transport rollers (39). ), these alignment elements being able to induce a controlled lateral displacement of the slab (24) in transit on the support and transport plane functionally correlated with the control of the axial position made by the element (36).

The device as in claim 12, characterized in that the alignment elements comprise elements (57) for regulating the inclination of at least some of the transport rollers (39) on the horizontal plane on which the rollers (39) remain. , the regulating elements (57) being governed by a control unit (30), which receives signals from the element (36), which controls the position of the axis (32) of the slab (24).

The device as in claim 13, characterized in that it comprises at least one regulating element (57a) in cooperation with one side of the transport rollers (39), and one regulating element (57b) in cooperation with the opposite side of the transport rollers (39).

The device as in claim 13 or 14, characterized in that the transport rollers (39) are connected to each other in groups, each group cooperating with a related element (57) to regulate its inclination.

16. The device as in claim 12, characterized in that the alignment elements comprise elements for the controlled lateral movement (33) of a truck (34) that supports the transport rollers (39) inside the heating furnace and / or maintenance of the temperature (15).

The device as in claim 12, characterized in that the alignment elements comprise elements for the controlled lateral movement (41) of the transport rollers (39), individually or in groups, of the heating furnace and / or maintenance of the temperature (15).

18. The device as in claim 12, characterized in that the alignment elements comprise differentiated control elements, individually or in groups, of the speed of rotation of the rollers (39) inside the heating oven and / or maintenance of the temperature (fifteen).

19. The device as in claim 18, characterized in that the rollers (39) of the heating and / or maintenance furnace (15) are inclined with respect to the support and transport plane, and are divided between the odd rollers ( 39a) and the even rollers (39b), including the neon rollers (39a) and the even rollers (39b), respective autonomous drive mechanisms governed by the respective control elements connected to these elements (36) to control the axial position of the slab (24).

The device as in claim 12, characterized in that the alignment elements comprise an actuating element (50) for the controlled lifting of one side of the transport rollers (39).

The device as in claim 20, characterized in that the transport rollers (39) are associated on the motor side with a stationary support (48), and on the opposite side with a support (49) that can be moved when less vertically.

22. The device as in claim 21, characterized in that the movable support (49) consists of a plane inclined towards the furnace (15) associated with a horizontally moving actuator (50).

The device as in claim 12, characterized in that the alignment elements comprise a controlled displacement element (53) for carrying a plurality of rollers (51), with a conical working plane and an axis substantially parallel to the axis ( 37) of the transport rollers (39), from a standby position on the side of, and outside the oven (15), to a position inside the oven (15) and in contact with the slab (24).

The device as in claim 23, characterized in that the tapered rollers (51) are mounted as cantilevers on the related supports (52) associated with a slider (53), this slider (53) including a first position, wherein the Related conical roller (51) is in a standby position on the side of, and outside of the furnace (15), and a plurality of positions, wherein the related conical roller (51) is in a position gradually further inside the furnace ( fifteen) .

The device as in claim 24, characterized in that each of the tapered rollers (51) includes a raised edge (55), substantially on its base.

26. The device as in claim 23, characterized in that the conical rollers (51) are configured out of phase on one side of the furnace (15) and the other, in an intermediate position between the transport rollers (39).

27. The device as in claim 23, characterized in that the tapered rollers (51) are configured in pairs of coaxial rollers on one side of the furnace (15) and the other, in an intermediate position between the transport rollers (39).

The device as in any of claims 23 to 28 inclusive, characterized in that the tapered rollers (51) include a working position constantly inside the furnace (15), with the respective raised edges (55) configured on the sides to a desired distance from the nominal position of the edges of the slab (24), with the function of limiting its displacement.

29. The device as in claim 12, characterized in that the alignment elements comprise transport rollers (39) including alternately related discs (40), half of which are grouped on one of the rollers (39), and the another half on the next of these rollers (39).

30. The device as in claim 12, characterized in that it comprises differential heating systems (28) configured downstream of the ingot mold (13), and cooperating with the proximity of the sides of the slab (24), these systems being able to creating on the sides of the slab (24) a differential thermal expansion functionally correlated with the control of the position of the axis (32) of the slab (24) with respect to the rolling axis (25). The device as in any of claims 12 to 29 inclusive, characterized in that it comprises a detector element (31) located downstream of the ingot mold (13), and a detector element (36) configured inside the heating furnace and / or maintenance of the temperature (15), or on its output.