BRPI0707959A2 - induction heating to control sheet metal planing - Google Patents

Abstract

INDUCTION HEATING TO CONTROL LAMINATED PLATE APPLIANCE. The present invention relates to a system for laminating sheet metal (1) having a substantially uniform planing, which includes a laminator including a pair of working rollers (5) to reduce the thickness of a metal strip, an induction heating (1Oa) close to at least one roller (5), bending jacks corresponding to each roller (5), and a cooling spray system (25) next to the rollers (5); a flattening measuring device (15) positioned to measure a gap in the flattening of the metal strip; and a laminator control interface (30) connected between the planing measuring device (15) and the laminator actuators, the laminator control interface (30) being configured to drive the induction heating device (10a), the bending jacks and the coolant spray system (25) to substantially eliminate flattening differentials in the flattening of the metal strip. The induction coil heating apparatus (1Oa) is configured to eliminate high voltage at the edges of the strip caused by temperature gradients in the working rollers (5) at the edges of the metal strip.

Description

Report of the Invention Patent for "INDUCTION HEATING APPLICATION TO CONTROL PLATE APPLICATION IN COLD LAMINATORS".

Cross Reference to Related Requests

The present invention claims the benefit of U.S. Provisional Patent Application 60 / 774,974, filed February 17, 2006, the full contents and description of which are incorporated herein by reference, as fully explained herein.

Field Of Invention

In one embodiment, the invention relates to cold rolling, and a method of perfecting plate flattening in cold metallaminated sheets using induction heating.

Background of the Invention

Metal composite strip products, such as aluminum, are typically laminated to four- or six-roller laminator chairs.

Earlier methods for forming aluminum strips did not allow laminar shoots evenly over their entire width, and did not allow to provide laminate products free from undesirable flattening undulations in the middle area, edge area or quarter area of the strip. Irregularly distributed internal efforts resulting from material processing with previous methods typically result in edge cracking, where edge cracks need to be discarded, resulting in the elimination and disposal of sections of the laminate product. Edge cracking in the middle of a coil may require discarding the entire coil.

Summary of the Invention

In general, according to the invention, in one embodiment, there is provided a method of forming sheet metal which employs induction heating to thermally expand the diameter portions of a single working roll in response to planing measurements taken from downstream metal taken from it. of the work roller. The method includes: laminating a sheet metal between a pair of working rollers to form a laminated product, measuring the stress distribution of the laminated product from a central portion of the laminated product to at least one edge portion of the laminated product; and

adjusting a temperature on a working roller single roller to provide a single roller edge diameter which is larger than a center diameter of the single roller when the tension of at least one edge portion of the rolled product is increased. that the tension of the central portion of the laminate product.

In one embodiment, adjusting the temperature of the single roller includes selectively heating the edge portions of the working roller to thermally expand the portions of the working roller corresponding to the longitudinal edge of the metal strip to have a larger diameter than center portion of the work roller to provide a work roller having a non-uniform diameter along its width. In one embodiment, inductive heating is employed to adjust the temperature, inductive heating being provided by induction heating coils that apply heat to the portions of the working rollers that correspond to the portion of the contact surface between the working roller. and longitudinal edge of the metal strip that is laminated. The contact surface between the work roller and the metal strip is called the work surface. In one embodiment, the temperature setting on the single roller includes two induction heating coils positioned close to the single working roller, where the heat applied by each induction heating coil has a magnitude that adjusts the thermal expansion along an axis length of one of the two. working rollers, such that the effect on the thermal crown roll opening on both rollers is completely compensated for.

In one embodiment, the stress measurements are provided by a planing bar positioned downstream of the work rollers that are in contact with at least one surface of the rolled product after being rolled by the work rollers. The planing bar may include a plurality of test rods which contact the top or bottom surface of the sheet metal. In another embodiment, voltage measurements may be optically provided by methods including but not limited to optical or laser scanning measurements. In further embodiment, voltage measurements can be provided acoustically.

In another embodiment, a method for forming a metal plate includes:

rolling a sheet metal between a pair of work rollers to form a rolled product;

the measurement of flattening of the laminated product; and

adjusting the diameter of a portion of a single working roller of the working roller pair corresponding to the longitudinal edge of the metal plate in response to the flattening of the laminated product.

In another aspect of the invention, there is provided a system for sheet metal sheet having a substantially uniform shape planing. In one embodiment, the sheet metal rolling system includes:

a rolling mill with at least one pair of work rollers;

an induction heating apparatus positioned close to a single working roller of the working roller pair;

a planing measuring device positioned downstream of the working roller pair; and

a rolling mill control interface connected between the planing metering device and the induction heating apparatus, where the rolling mill control interface is configured to receive planing measurements from the planing metering device and to providing signals to drive the induction heating apparatus to provide a laminate product having substantially uniform voltage distribution across the width of the laminate product.

In one embodiment, the induction heating apparatus is configured to eliminate the high tension at the edges of the strip that may be caused by the temperature gradient in the working rollers at the dated metal edges. In one embodiment, the induction heating apparatus may additionally include bending jacks, work roller axial sliding mechanisms and a spray cooling system, where the bending jacks, axial sliding mechanism and Spray cooling systems can also be actuated by the Laminator control interface in response to planing measurements.

Brief Description of the Drawings

The following detailed description, provided by way of example, and not intended to limit the invention solely to the same, will be best provided in conjunction with the accompanying drawings, in which like reference numerals indicate similar elements and parts, in which: Figure 1 is a schematic view illustrating one embodiment of a system for controlling the flattening of the laminated sheet according to the invention;

Figure 2a is a perspective view illustrating one embodiment of a system for controlling the flattening of the laminate plate including two induction heaters corresponding to a single working roller according to the invention;

Figure 2b is a perspective view illustrating another embodiment of a system for controlling the flattening of the laminate plate including four induction heaters in a stacked arrangement and corresponding to a single working roller according to FIG. invention.

Figure 2c is a perspective view illustrating another embodiment of a system for controlling flattening on a laminate plate including four induction heaters in a winged side arrangement and corresponding to a single working roller according to FIG. the invention;

Figure 2d is a perspective view illustrating one embodiment of a cold laminator according to the present invention;

Figure 3 is a graph illustrating an embodiment of a working roller in which the edge portions have been thermally expanded to provide a working roller having a non-uniform diameter along the width of the roller; is a graphical representation of the stress distribution of an induction heated laminate product on the edge portions of a single working roller according to the present invention compared to a non-induction heated laminate product on the edge portions of a single working roller. work roller;

Figure 5 is a graphical representation of the stress distribution of an induction heated laminate product in the edge portions of a single working roller according to the present invention compared to a non-induction heated laminate product in the portions of a single roller. edge of a work roller.

Detailed Description of Preferred Embodiments

Detailed embodiments of the present invention are described herein; however, it should be understood that these are merely illustrative of the invention, which may be embodied in various forms. In addition, each example provided in connection with the various embodiments of the invention is intended to be illustrative and not restrictive. Moreover, the figures are not necessarily to scale, some features may be exaggerated to show specific component details. Therefore, the specific structural and functional details described herein should not be construed as limiting, but merely as a basis for representation. teach one of skill in the art to employ the present invention in a variety of ways.

Figure 1 is a schematic representation of a cold rolling system 100, wherein the cold rolling system 100 includes at least two working rollers 5, an induction coil heating apparatus 10a, and a heating device. planing measurement 15 configured to measure the surface planing of a metal strip 1 which is rolled by the work rollers 5. The work rollers 5 are disposed opposite each other, in which the opening between the work rollers 5 is called the opening 4. The work rollers 5 may be of steel or other rigid metallic material. The plate to be laminated is inserted between the working rollers 5, being rolled and drawn in one direction of arrow Z. In one embodiment, the metal strip 1 is aluminum or an aluminum alloy. In one embodiment, the metal strip 1 has a thickness prior to lamination ranging from approximately 10.16 mm (0.400 ") to approximately 0.254 mm (0.010"). In yet another embodiment, the metal strip is an aluminum alloy that can be rolled as thin as approximately 0.2032 mm (0.008) inches, but it is noted that even smaller thicknesses are possible where the thickness of the rolled product may be. depending on the intended application of the laminated product.

Cold rolling indicates sheet metal processing that has been cooled to room temperature, but in the course of numerous aluminum sheet cold rolling passages, the temperature of the material may be raised to approximately 165.5 ° C (330 ° C). ° F). Although the following description is generally directed to cold rolling, it has been contemplated that the following method and apparatus may also be applied in hot-melting, which is within the scope of the present invention. Aluminum foil hot rolling is generally characterized by processing temperatures ranging from approximately 287.7 ° C (550 ° F) to approximately 482.2 ° C (900 ° F). It is noted that the above temperatures are provided for illustrative purposes only and are not intended to limit their invention as the processing temperatures may be modified by various processing conditions such as the rolling speed, the number of lamination passes. cold, and the degree of cooling between the lamination passages.

Referring to Figures 1 and 2a-2d, during rolling inconsistencies between the roll opening profile 4 and the thickness cross-sectional distribution of the metal strip 1 entering the work rollers 5, typically flattening defects may result. visible as wavy edges or wavy central portions of the laminate. The thickness cross-distribution of the metal strip 1 is defined by the thickness of the metal strip measured from the upper surface of the metal strip to the lower surface of the metal strip across the width of the metal strip W1. The roll opening profile can be defined as the dimension separating the opposing work surfaces 4a, 4b from the work rollers 5, where the dimension separating the opposing work surfaces 4a, 4b from the work rollers 5 during lamination may not be uniform across the wide working rollers 5. Differences between the geometry of the aperture 4 and the thickness cross-sectional distribution of the metal strip 1 may result in inconsistencies in the stretching of the metal strip 1 across the width of the metal strip W1 after lamination which may manifest as flattening defects in the laminated product.

Disharmony or inconsistencies in the roll opening profile 4 and the cross-thickness distribution of the metal strip 1 that typically result in flattening defects may result from an exerted force on the working rollers 5 by the metal strip 1 which is laminated. , which may be called flexion deflections. Disharmony or inconsistencies between the roll aperture profile 4 and the cross-salt thickness distribution of the metal strip 1 that typically result in defects in planing may also result from thermal expansion of the work roller 5, which is at least partially attributed to the frictional heat of the rolling process which creates a thermal bulging of the working surfaces 15. The temperature at which each of the working rollers 15 typically peaks at the intermediate point M1 of the width W1 of the rollers. of work; For this reason, the thermal expansion on each of the work rollers 5 is typically the largest at the intermediate point M1 of the work roller and decreases towards the edges of the rollers, which may be called the thermal crown.

During winding, the laminated product may be stretched under tension, where flattening defects may manifest as drawn edges, which may be prone to breakage. The formation of recessed edges on the edge portion of the metal strip that is at a higher tension than the central portion of the metal strip is typically the limiting factor in the winding speed of the previous methods. It is noted that although bending jacks, refrigerant sprays, mechanically ground crowns on the work rollers, and lateral work roll displacement mechanisms can have a positive effect on reducing flattening defects in the central portions of the laminate product. Such mechanisms do not provide a substantial reduction in the flattening defects formed on the edge portion of the metal strip, such as the formation of drawn edges.

In one aspect of the present invention, a substantial increase in the reduction of drawn edges has been realized using an induction heating apparatus 10a, 10, 10c, 10d configured for expanding thermal portions of a single working roller of the pair of working rollers. corresponds to the edge 13a, 13b of the metal strip 1. The term "substantially uniform stress distribution across the width of the laminate" indicates that when external tension is removed from the laminate, the laminate is placed on a flat surface. there will be substantially no release of the laminate from the flat surface on which the laminate is placed. The term "substantially no release" indicates that the bottom surface of the laminate is fully in contact with the flat surface on which the laminate is placed. External stress is the stress that is imposed on the plate during winding after rolling. In one embodiment, in order to flatten the laminated product, the longitudinal fibers across the width of the laminated products may be substantially the same in the absence of external tension.

Referring to Figures 1-2d, in one embodiment, the present invention measures the flattening and flattening defects in the metal strip being rolled, such as drawn edges, and in response to the measured flattened defects. , takes a corrective action that includes at least induction heaters that correspond to the edge portions of a single work roller. In one embodiment, the flattening measurements of the metal strip 1 are provided by a flattening measuring device 15, which is positioned downstream of the work rollers 5 to measure the flattening of the laminated product. In one embodiment, the planing measuring device 15 may be a planing bar configured to measure a voltage distribution of the laminated product from the central portion of the laminated product to the edge portion of the laminated product. The term "measuring a stress distribution from a central portion of the laminate to an edge portion of the laminate" indicates that the stress can be measured in increments of the laminate centre across the width of the laminate to the edge of the laminate product, where each increment can be considered a path that extends longitudinally along the length in the direction in which the laminate can be laminated.

In one embodiment, the plurality of rotors measure the transverse stress distribution across the width of the metal strip 1. The planing bar may include a plurality of test rods that contact the surface of the metal plate. More particularly, the laminated product is tension-wound where, prior to winding, the mined product contacts the planing bar under which a force is induced in the y direction over the planing bar poor, as shown in Figures 2a -2c. As discussed above, in some embodiments, the winding stress confers a plate that may appear to be visually boring while it is wound, but this external stress application will not correct the differences in elongation that manifest as defects in tension. flattening when the external stress is removed. In response to the external stress applied during winding, the stress distribution is effected across the width W2 of the laminated product, where the stress distribution in the laminated product is correlated to the force induced by the sheet metal. each of the test bar rods. In one embodiment, the planing bar may include a plurality of rotors 15A, preferably having a width of 12.7 to 76.2 mm (0.5 "to 3.0") arranged along an axis where each rotor measures the force along a path corresponding to the tension of the metal strip 1 which is laminated.

In another embodiment, the flattening of sheet metal 1 may be optically measured or may be characterized using lasers. In yet another embodiment, the planing measuring device may also include a non-contact system that measures the stress distribution of the metal strip using acoustic measurements. Acoustic measurements can be provided by sine modulation of a vacuum under the metal strip 1.

It is noted that the above planing measuring devices 15 are provided for illustrative purposes and that the present invention is not considered limited thereto, as any planing measuring device capable of measuring the planing may be used. of the metal strip 1 being laminated, or determining the transverse stress distribution across the width of the metal strip 1, being within the scope of the invention.

Referring to Figures 1-2c, the induction heating apparatus 10 may be operated in response to defects in the planning and tension differentials in the metal strip 1. Induction heating is a method by which steel work rollers are heated by a non-contact method of using an alternating magnetic field. In one embodiment, the induction heating apparatus is comprised of at least one power source that provides a power output at the required mains frequency and an induction coil assembly. The power supply triggers a high frequency alternating electrical current through induction coil assembly. The alternating magnetic field induces a stream of current in the single working roller that can be termed stemming parasites. The current flow through the work roller increases the temperature in the work roller 5 through joule heating. In one embodiment, each induction coil 10 may include a ferromagnetic core. The induction coil heating apparatus 10 may additionally include at least one cooling passage to provide a coolant or may not include cooling passageways.

In one embodiment, the current through the electrically conductive coil may be in the order of about 80 amps to about 200amps. In one embodiment, the power supply for the induction heater has a fixed operating frequency, where the frequency of the electric current signal sent to the heating coil is about 20KHz. The current wave for the induction heater is sinusoidal with varying amplitude. The energy for induction heaters is adjusted by changing the amplitude of the sine wave over a set number of cycles in a repeating pattern. The duration of the repeating pattern is about 8 cycles of the operating waveform. At full power, the current signal is a 20 kHz sine wave with constant amplitude. It is noted that the above currents and frequencies are provided for illustrative purposes and are not intended to limit the present invention as other currents and frequencies have been contemplated and are within the scope of the present invention. In addition, other modes of providing energy have also been contemplated and are within the scope of the present invention.

In one embodiment, the temperature setting of the single working roller includes induction heating coils 10 to induce heating in the portions of the working roller 5 adjacent the working surface corresponding to the edges of the metal strips 13a, 13b. More specifically, the induction heating coils 10a, 10b, 10c, 10d are aligned with the portion of the working roller that contacts the longitudinal facing 13a, 13b of the metal strip which is laminated to provide the laminated product, where the longitudinal edge 13a, 13b extends along the rolling direction. Referring to Figure 2a, in one embodiment, the adjustment of the heat generated by the single-working induction heating induction heating apparatus includes an induction heating coil 10a, 10b positioned at each end of the roller 5, where each induction heating coil 10a, 10b corresponds to each edge of the metal strip 1. In another embodiment, the adjustment of the heat generated by the induction heating apparatus on the single working roller 5 includes two induction heaters 10a, 10b corresponding to each edge 13a, 13b Figure 1b, where the positioning of the induction coils is in a stacked configuration which may correspond to the circumference of the working roller as shown in Figure 2b. In an additional embodiment, the induction heating apparatus may include two coils corresponding to each edge 13a, 13b of the metal strip 1, where the coils are positioned adjacent to each other as shown in Figure 2c.

In one embodiment, each induction coil 10 may correspond to the portion of the work roller 5 adjacent the working surface contact surface to which the metal strip 1 is being laminated, which may also be referred to as the work surface. In another embodiment, each induction coil 10 may be laterally disposed in a direction parallel to the axis of rotation of the roller to reposition the coils at or near each end of the strip. With the provision of induction coils 10 which can be laterally arranged, the position of the induction coils can be positioned to account for the different widths of the metal strip. In addition to the provision that each induction coil can be disposed laterally, the induction coils may also include a mechanism for adjusting the gap between the induction coil and the work surface of the work roll. In one embodiment, a hydraulic cylinder with a position control moves the induction coil forward until contact with the roll is formed and then backs off the work roll by approximately 3 mm. It is noted that other dimensions for the opening for the induction coil of the work roll have also been contemplated and are within the scope of the present invention as long as the degree of separation allows for the effective coupling of the aorole coil magnetic field so that eddy currents are induced in the roller.

In one embodiment, induction heaters 10a, 10b, 10c, 10d have sufficient heat to thermally expand the diameter of a single working roller corresponding to the edge of the metal strip to be larger than the diameter of a central portion of the single roller. The term "single working roller" denotes a working roller of working roller 5, where the single working roller may be either the upper working roller or the lower working roller of the working roller pair. The term "single roller edge diameter" indicates the diameter of the portion of the single roller that corresponds to the longitudinal edge 13a, 13b of the metal plate. The term "center diameter of the single working roller" indicates the diameter of the portions of the roller between each single bore edge diameter.

In embodiments of the present invention in which the heat induction coils are positioned relative to a single working roller of the working pair of rollers, the energy applied by the induction heating coils to increase the surface temperature is of a magnitude that can provide further expansion. at the working section of the working roller adjacent the edges of the metal strip 13a, 13b with respect to the expansion of the center section of the working roller. Figure 3 pictorially depicts the induction heating effect on the sole working roller 5 to increase the edge diameter of the single roller corresponding to the longitudinal edge 13a, 13b of the metal strip 1, where the reference line 50 represents thermal expansion across the width of the single working roller which is heated by induction heating according to the present invention, and reference line 51 represents the thermal expansion along the width W1 of the opposite roller which is not heated by heat by induction. The degree of thermal expansion is directly related to the temperature of the roller, where the portions of the roller having higher temperatures have a higher degree of thermal expansion.

In one embodiment, the degree of thermal expansion in rollersingular 50 is selected to compensate for thermal expansion 51 in the opposite lamination which does not include induction heaters. More specifically, as represented by reference line 50, the greater thermal expansion in the work roller sections 5 that are adjacent to the longitudinal edge 13a, 13b of the metal strip on the work roller featuring induction coils shifts the increase in thermal expansion in the working roller sections adjacent to the metal strip of the opposite working roller which does not feature induction heating coils, where the decrease in thermal expansion may be termed the printing effect. The combination of the highest thermal expansion at the strip edge on the single working roller and the normal impression at the opposite diameter of the opposite working roller gives the equivalent of a uniform roll opening to the strip that is deformed across its width and results. in a strip having a uniform flatness substantially free of drawn edges at the milling machine outlet. More specifically, the thermal expansion on the edge diameter of the single working roller is selected to compensate for the opposite ring having a larger diameter in the center of the opposite roller compared to the opposite diameter of the opposite roller. In one embodiment, the change in dimension in the rim diameter of the labular roller may be about 0.0127 mm (0.0005 inches), in which larger and smaller degrees of expansion were contemplated, since the degree of Thermal expansion required to correct flattening defects may be effected by the process conditions which include, but are not limited to, the rolling speed, the selection of laminated product material, the degree of heating provided by the heater. induction, as well as the degree of refrigerant applied to the center portion of the work roller.

Referring to Figure 1, the rolling mill 100 may also include a refrigerant spray system 25 near the portion of the single working roller 5 which is in contact with the stripped metal strip 1. The refrigerant spray system 25 may spray a coolant 25A on the portion of the single working roller 5 which is in contact with the metal strip 1, where the coolant removes a portion of the heat generated by lamination of the metal strip. 1 on the work rollers 5. The removal of the heat generated on the work rollers 5 by lamination of the metal strip through the refrigerant spray systems cannot reduce the formation of a thermal crown which contributes to flattening and blemish defects. of the jerked.

Referring to Figure 1, in addition to adjusting the heat generated by the unique work nozzle 5, the differential in flattening the laminated product sheet can be further reduced by mechanically generating a force that flexes the work rollers in a direction opposite to the fle of the roll caused by the force generated by the metal strip 1 on the working roller 5 during rolling. In one embodiment, the roll bending jacks 21 and / or side roll displacement mechanisms may be used to generate a roll opening adjustment that compensates for the roll bending defects resulting from the force generated by the working norol strip during rolling operations.

In one embodiment, the bending jacks are configured to provide a force opposite to the bending of the roll generated by the metal strip 1 and may be called positive bending jacks 21. More particularly, the bending jacks 21 are configured to compensate for force produced by the metal strip 1 against the surface of work roller 5 which is in contact with metal strip 1 during rolling, where metal strip 1 produces forces on the upper and lower work rollers that cause them to bend and are bent away from the strip.

In another embodiment, the Laminator 100 may additionally include bending jacks 20 corresponding to each work roller 5, where the bending jack 20 may move a portion of the work rollers 5 along the y axis to substantially reduce the effect of the bend. thermal crown on the metal strip 1 and to facilitate, together with the cooling spray of the roll 25, the formation of a metal strip 1 having a substantially uniform flattening through the central portion of the strip but allowing the outer edges of the strip under tension. These bending jacks 20 may be referred to as negative bending jacks, flexing the working roll in a direction opposite to the positive bending jacks 21.

The amount of bending jack force required and its direction are determined by the combination of the degree of flexing of the work roller 5 caused by the strip force, the grinding crown on the work roller, and the amount of expansion. roller on the work roller 5.

In another embodiment, the work rollers 5 may also include a work roll side shift mechanism (not shown) which is configured to move each roll 5 along a substantially horizontal axis, such as the x axis, as shown in Figures 2a -2c. In one embodiment, the roll diameter of each of the opposing working rollers is ground to vary along its axis, where the axial displacement of the various rollers to manipulate the roll opening 4 has a correction factor that can be employed in response to measured planing defects. More particularly, the working rollers having varying diameters, when axially displaced by the working roller lateral displacement mechanisms, provide another means to reduce the effects of thermal crowning and roll deflection from the strip force.

In one embodiment, a pair of spare rollers 6 may be employed in conjunction with the working rollers 5 in a configuration typically referred to as a four-roll laminator chair. The spare rollers 6 are used to support the working rollers and minimize their bending in response to the force of the strip. In an additional embodiment of the present invention, a pair of intermediate rollers 8 may be arranged between the spare rollers 6 and the working rollers 5 in a configuration typically termed a six-roller laminator chair. Intermediate rollers may also include intermediate lateral displacement mechanisms and intermediate roller bending jacks.

The lamination system 100 also includes a laminator control interface 30 connected between the flattening measuring device 15 and the laminator actuators. The Iamine-pain control interface 30 receives a signal from the planing measuring device 15 representing differential measurements on the sheet metal flattening of the metal strip 1 or the voltage distribution across the width of the metal strip 1. laminator control 30 then processes and analyzes the signal against a predetermined target planing value or stress distribution. In one embodiment, the rolling mill control interface processes the measured signals and formulates the control outputs for rolling mill actuators based on a set of mathematical algorithms. In one embodiment, the laminator interface 30 includes a computer. The rolling mill control interface 30 then sends actuation signals at least to the refrigerant spray system 25, bending jacks 20 or induction heating coils 10 to compensate for the measured differentials in flattening the plate or in the cross-sectional stress distribution of metal resulting in a metal strip 1 having a substantially flat surface that is substantially free of drawn edges and thermal crown effects.

Although the invention has been described above, in general, the following examples are provided to further illustrate the present invention and to demonstrate some advantages arising therefrom. It is intended that the invention be limited to the specific examples described.

Examples

Figure 4 graphically depicts a stress distribution across the laminated product which is provided by induction heaters corresponding to the edge diameter of a single working roller as compared to the stress distribution provided by a similarly prepared laminate without heat heating. induction. Referring to Figure 4, the vertical axis represents the tension (pounds per square inch) that is measured in the rolled product, and the horizontal axis represents the width of the rolled product, where the stress measurements were incrementally recorded from a planing bar. wherein each zone of the sheet corresponds to the sheet width of the laminated product. The voltage distribution recorded in Figure 4 is normalized to the nominal winding voltage, which can be in the order of 3000 Psi. The stress distribution shown in Figure 4 was produced by an Aluminum Association series 3003 aluminum alloy metal strip, laminated by a single chair cold laminator of a thickness of approximately 0.899 mm to 0.4318 mm (0.035 "to 0.017 mm). ") at a speed of approximately 190.5 m / min (625 feet / min). The metal strip that was cold rolled by the laminator had a width in the order of about 1320.8 mm (52 ").

The strip distribution of metal strip, processed according to the present invention 61, includes a thermal control with induction heaters positioned corresponding to portions of a single working roller that correspond to the strip edge of the single working roller and a refrigerant spray system. roll corresponding to at least a portion of the central portion of the work roller. The stress distribution of the metal strip processed in accordance with the present invention additionally included bending jacks configured to flex the working rollers in one direction to counteract the normal bending caused by the force produced on the working roller by the metal strip. Additionally, the tension distribution of the metal strip processed in accordance with the present invention additionally included a planing measuring device and a rolling mill control interface, where the voltage measurements taken from the measuring device The planing parameters were analyzed by the rolling mill control interface and, in response to the stress-measurement correction factors, were actuated on the bending jacks, the roller cooling system, and the induction heaters. Comparative example60 was a metal strip that had been processed with roll bending and cooling jacks to perfect the measured planing, but did not include induction heaters positioned corresponding to a single working roller and thermally oriented to expand the diameter of the roller. greater than the central diameter of the work roll.

In comparative example 60, an increase in stress beyond 6.9MPa (1000 psi) is measured at the edge portions of the laminate as indicated by the portions of the planing gauge corresponding to zone 1 and zone 20 of Figure 4. consequently indicating the incidence of drawn edges in the laminated product. The central portions of the laminate of comparative example 60, as indicated by zones 3 to 17, have a substantially uniform stress distribution that substantially indicates no flattening defect in the central portion of the laminate. Zones 2 and 19 have a low voltage and may be referred to as relaxed zones, which have a recorded voltage that is less than the externally applied voltage, the externally applied voltage including but not limited to the winding voltage. Comparative example 60 indicates that although bending jacks 20 and refrigerant spray system 25 reduce the effect of the thermal crown on the central portions of the work rollers 5, bending jacks and refrigerant spray system no longer reduce the incidence of drawn edges and the adjacent relaxed zone.

The effects of the thermal crown can be further reduced in combination with substantially eliminating the incidence of repeating edges by using induction heating coils 10 to introduce heat to a single working roller 5 corresponding to longitudinal edges 13a, 13b of metal strip 1, where heat-induced heat expands the diameter of the working roller edge. Compared to comparative example 60, the voltage distribution 60 corresponding to the metal strip, processed using the induction heating according to the invention, has a decrease in the tension measured at the longitudinal edge of the laminate to approximately 500 psi or less, as indicated by the portions of the metal. flattening measuring device corresponding to zones 1 to 20 of Figure 4, substantially reducing the incidence of relaxed zones such as zones 2 and 19.

By reducing the incidence of drawn edges, in one aspect of the present invention, the winding speed can be increased without resulting in edge breakage. Figure 5 depicts the stress distribution 61 of a laminated product processed in accordance with the present invention, including thermal control by induction heaters, positioned corresponding to portions of a single working roller corresponding to the strip edge, and Comparative example 60 not including induction heaters, in which the winding speed of approximately 1250 ft / min (381 m / min) of the laminated product processed in accordance with the present invention is twice as high. winding speed of the comparative example, which is 625 ft / min (190.5 m / min). Each of the laminated products shown in Figure 5 is made of an Aluminum Association 6061 aluminum alloy, and is processed through a two-chair cold laminator from a thickness of approximately 0.125 ". (3.175 mm) at approximately 0.0226 "(0.57404 m).

Referring to Figure 5, in one example, the use of induction heating to thermally heat the portion of the single roller corresponding to the longitudinal edge of the laminated product has a stress distribution 61 which, when compared to a laminated product which does not use radiant heating. The induction according to the present invention allows an increase of approximately 381 m / min (1250 ft / min) without increasing the edge tension to a level resulting from winding at 190.5 m / min (625 ft / min). without induction heating. More particularly, while the comparative example coiled at a speed of approximately 190.5 m / min (625 ft / min) resulted in a stress of about 2000 psi, the stress distribution of a laminated product processed using heat By induction according to the present invention, it allowed a winding speed of 381 m / min (1250 ft / min) while having a measured edge tension of approximately 750 psi or less.

While the present invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that prior changes and other changes in shape and detail may be made without departing from the spirit and scope of the present invention. Accordingly, it is intended that the present invention is not limited to the exact forms and details described and illustrated, but is within the scope of the appended claims.

Claims (20)

A method of fabricating sheet metal comprising: laminating a sheet metal between a pair of working rollers to form a rolled product, measuring the stress distribution of the rolled product from a central portion of the rolled product to at least one portion edge of laminated product; and adjusting a temperature on a single roll of the working roll to provide a single bead edge diameter will be greater than a central diameter of the single roll when the tension of at least one edge portion of the laminate is greater than the tension of the central portion of the laminate product. The method of claim 1, which comprises measuring the stress distribution with a planing bar. A method according to claim 1 which comprises optical or acoustic measurement of voltage distribution. A method according to claim 2, comprising a planing bar for measuring the stress distribution of the downstream plate from the working roller pair. A method according to claim 2 comprising at least one induction coil near a portion of the single working roller corresponding to the longitudinal edge of the sheet metal. The method of claim 4, wherein each induction coil may be displaced laterally along a unique working width. A method according to claim 1 further comprising a refrigerant spray system configured to lower a temperature in at least a central portion of the working roller pair. The method of claim 1 further comprising bending jacks configured to compensate for a force produced by the metal strip against the working roller during rolling. A method of fabricating sheet metal, comprising: laminating a sheet metal between a pair of work rollers to form a rolled product, measuring the flattening of the rolled product; and adjusting the diameter of a portion of a single working roller of the working roller pair corresponding to the longitudinal edge of the metal plate in response to the flattening of the laminated product. A method according to claim 9, wherein the diameter of the portion of the single working roller is adjusted to provide a finished product having a substantially uniform stress distribution across the width of the laminated product. A method according to claim 9, comprising measuring the planing with a planing bar. A method according to claim 9, comprising inducing a magnetic field that induces stray currents in the single working roller. A method according to claim 9, which comprises opposing at least one induction coil aligned with respect to a longitudinal edge of the sheet metal. A method according to claim 9, which comprises forming a refrigerant spray system in response to the laminate product planing. The method of claim 9 further comprising acting bending jacks in response to the flattening of the laminate product. A sheet metal rolling system comprising: a laminator with at least one pair of working rollers, an induction heating apparatus positioned close to a single working roller of the working roller pair, a flattened measuring device positioned downstream from the pair of work rollers; An Iaminator control interface connected between the planing measuring device and the induction heating apparatus, where the Iaminator control interface is configured to receive the planing measuring device's flattening measurements and to send signals to trigger the induction heating apparatus. A system according to claim 16 further comprising at least bending jacks, a spray cooler system or a roller lateral displacement mechanism for displacing the working rollers in opposite directions along their horizontal axes. . The system of claim 17, wherein the Laminator control interface receives a signal from the planing measuring device, analyzes the signal, and drives at least one working side shifter, the bending jacks, the induction heating apparatus and the refrigerant spray system for providing a laminate product having a substantially uniform voltage distribution across the width of the laminate product. The system of claim 16, wherein the induction heating apparatus is an induction coil wound around a ferromagnetic core. The system of claim 20, wherein the laminator is a cold laminator.