CN114585753A - Quick quenching production line - Google Patents

Abstract

The rapid quench line may be adapted for hot coils at or above the recrystallization point of the metal strip. The hot web may be unwound from a low tension unwind reel using a non-contact nip. The strip of metal exiting the hot coil is rapidly quenched (e.g., at 100 or 200 ℃/s or a rate greater than 100 or 200 ℃/s) through a plurality of quenching zones. The coolant may be removed, such as with an air knife and/or eraser (e.g., an ultra-soft eraser). Steam may be collected from earlier quench zones and re-used to provide humid air to the metal strip, such as in the region where the temperature of the metal strip is at or below the leidenfrost point. The cooled metal strip may be passed through a tensioning member to increase the tension in the metal strip before it is optionally lubricated and then rewound or otherwise further processed.

Description

Quick quenching production line

Reference to related applications

This application claims the benefit of U.S. provisional patent application No. 62/915,915 entitled RAPID query LINE filed on 16/10/2019, the contents of which are hereby incorporated by reference in their entirety.

Technical Field

The present disclosure relates generally to metal working, and more particularly to controlling the temperature of a metal article during production of the metal article.

Background

The metallographic structure of a metal article can have a significant effect on various properties of the metal article, such as the strength and/or formability of the metal article. During the production process, care must be taken to ensure that the metal product produced has the desired metallurgical properties. Precise control of the temperature of the metal product during its production enables the metal product to be produced with the desired metallurgical properties and the desired metallographic structure.

Direct Chill (DC) casting and continuous casting are two methods of casting solid metal from liquid metal. In DC casting, liquid metal is poured into a mold with a collapsible false bottom that can be withdrawn at the rate at which the liquid metal solidifies in the mold, typically resulting in a large and relatively thick ingot (e.g., 1500 mm x 500 mm x 5 m). The ingot may be processed, homogenized, hot rolled, cold rolled, annealed and/or heat treated and otherwise finished prior to being wound into a metal strip product that may be distributed to customers of the metal product (e.g., automotive production equipment).

Continuous casting may include continuously injecting molten metal into a casting cavity defined between a pair of movable opposed casting surfaces and withdrawing a cast metal article (e.g., a metal strip) from an outlet of the casting cavity. Continuous casting can produce metal articles of any suitable length, which can be particularly suitable for producing coilable metal strip.

Typically, the metal article must be hot worked to obtain the desired metallurgical structure and/or metallurgical properties. Examples of such heat treatments include high temperature annealing or homogenization, both of which involve heating the metal article to a relatively high temperature. Annealing is a high temperature treatment of a worked (e.g., work-hardened) metal article, typically at or near the recrystallization temperature of the metal (e.g., around 300-400 ℃ for some types of aluminum alloys). Homogenization is the high temperature treatment of the metal article to reduce the grain-level heterogeneity of the as-cast microstructure. Homogenization is generally carried out at a temperature above the recrystallization temperature of the metal, such as around 450-600 ℃ in some types of aluminum alloys, depending on the alloy system. When heated to these temperature ranges (e.g., at or above the recrystallization temperature), the metallurgical microstructure of the metal article may become more homogeneous, thereby improving the formability and/or other metallurgical properties of the metal article. However, at these high temperatures, the metal articles are particularly susceptible to damage if handled improperly. Typically, the DC ingot is annealed or homogenized.

Annealing or homogenizing of metal strip, such as coiled metal strip, typically requires the use of continuous annealing and solution heat treatment (CASH) lines. These CASH lines take up a very large footprint and require a number of special pieces of equipment designed to unwind the metal strip, float the metal strip through a furnace and a cooling zone, and rewind the metal strip. Physical contact with rollers and the like may damage fragile metal strips without floating the metal strip when it is at high temperatures. The path taken by the metal strip through the CASH line is typically long and circuitous, requiring the rejection of long lengths of metal strip as it needs to be run through the CASH line to begin processing. In addition, to avoid having to scrap these large quantities of metal strip per coil, the CASH line typically requires the use of hoppers and cutters to combine the individual coils together into a continuous metal strip, which is then cut into individual process coils.

Disclosure of Invention

The term embodiment and similar terms are intended to refer broadly to all subject matter of the present disclosure and claims below. Statements containing these terms should be understood as not limiting the subject matter described herein or the meaning or scope of the claims below. Embodiments of the disclosure encompassed herein are defined by the following claims, not this summary. This summary is a high-level overview of aspects of the disclosure and introduces some concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this disclosure, any or all of the drawings, and each claim.

Embodiments of the present disclosure include a system comprising: a low-tension unwinding unit for receiving and unwinding a metal coil of metal strip; a non-contact compaction device positioned adjacent to the low tension unwind unit to provide a force on the metal strip toward a center of the metal roll during unwinding of the metal roll; a set of quenching zones for cooling the metal strip, wherein the set of quenching zones provide sufficient coolant to reduce the temperature of the metal strip at a rate of at least 100 ℃ per second; a coolant removal unit positioned downstream of the set of quench zones; and a tensioning unit positioned downstream of the coolant removal unit for increasing tension in the metal strip.

In some cases, the low tension unwind unit includes insulation arranged to retain heat within the wound portion of the metal coil. In some cases, the low-tension unwind unit includes a heat source for providing heat to a wound portion of the metal roll, wherein the heat source is coupled to a controller for maintaining the metal roll at or above a threshold temperature. In some cases, the non-contact compaction device includes one or more magnets for generating a varying magnetic field through the metal strip. In some cases, the varying magnetic field is configured to distribute the force over a width of the metal strip over time. In some cases, the non-contact compacting apparatus includes a nozzle for blowing heated air toward the metal strip. In some cases, the system further comprises: a flatness measurement unit positioned to measure a flatness of the metal strip; and a controller coupled to the flatness measurement unit and the set of quenching zones to adjust the delivery of the coolant based on the measured flatness of the metal strip. In some cases, the system further includes a stabilization system positioned upstream of the set of quenching zones to introduce waves into the metal strip. In some cases, the metal strip remains supported without mechanical contact between the metal coil and the coolant removal unit. In some cases, the set of quenching zones includes a vapor recovery module for redirecting humid air from at least one of the set of quenching zones toward the metal strip at a location downstream of the at least one of the set of quenching zones. In some cases, the location downstream of the at least one quenching zone in the set of quenching zones is a location where the temperature of the metal strip is equal to or below the Leidenfrost (Leidenfrost) point. In some cases, the system further comprises: a pre-quench heating unit positioned downstream of the low tension unwind unit; and a controller coupled to the pre-quench heating unit to heat the metal strip to a target temperature before the metal strip enters the set of quenching zones. In some cases, the non-contact compaction device is positioned to provide a force to the metal strip at or near a location where the metal strip disengages from the coil due to gravity.

Embodiments of the present disclosure include a method comprising: unwinding a hot metal coil using a low tension unwinder, wherein unwinding the hot metal coil comprises applying a non-contact pinch force to the hot metal coil and allowing metal strip of the hot metal coil to disengage from the metal coil; rapidly quenching the metal strip in a set of quenching zones, wherein rapidly quenching the metal strip comprises applying a coolant to the metal strip to reduce the temperature of the metal strip at a rate of at least 100 ℃ per second; removing the coolant from the metal strip; and applying a downstream tension to the metal strip.

In some cases, the method further comprises maintaining an initial temperature of the hot metal coil at the low-tension uncoiler. In some cases, the method further comprises preheating the metal strip immediately prior to rapidly quenching the metal strip. In some cases, applying the non-contact compressive force comprises generating a varying magnetic field through the metal strip. In some cases, applying the non-contact compaction force comprises blowing heated air against the metal strip. In some cases, the method further comprises: measuring the flatness of the metal strip; and adjusting the delivery of the coolant based on the measured flatness. In some cases, the method further comprises inducing a wave in the metal strip without contacting the metal strip. In some cases, the method further comprises: capturing steam from at least one of the quenching zones; and redirecting the captured steam toward the metal strip. In some cases, redirecting the captured steam includes redirecting the captured steam toward the metal strip at a location where the temperature of the metal strip is at or below the leidenfrost point.

Drawings

The specification refers to the following drawings, in which the use of the same reference numbers in different drawings is intended to illustrate the same or similar components.

Fig. 1 is a schematic side view of a system for rapidly quenching and rewinding a hot metal coil according to certain aspects of the present disclosure.

Fig. 2 is a schematic side view of a system for rapidly quenching a hot metal coil for further rolling according to certain aspects of the present disclosure.

Fig. 3 is a schematic block diagram of a rapid quench production line in accordance with certain aspects of the present disclosure.

FIG. 4 is a combined schematic block diagram and temperature profile depicting the relative temperature of a metal strip passing through a rapid quench production line in accordance with certain aspects of the present disclosure.

Fig. 5 is a schematic side view of a vapor recovery module on a rapid quench production line according to certain aspects of the present disclosure.

Fig. 6 is a schematic top view of a magnetic rotor non-contact pressure roller according to certain aspects of the present disclosure.

Fig. 7 is a flow chart depicting a process of rapidly quenching a hot metal coil in accordance with certain aspects of the present disclosure.

Detailed Description

Certain aspects and features of the present disclosure relate to a rapid quench line suitable for hot coils or coiled metal strip having a temperature near, at, or above the recrystallization point of the metal strip. The recrystallization point may be between or about 40% and 50% of the melting temperature of the metal strip. The rapid quench line may include a low tension uncoiler that utilizes a non-contact hold down device. The metal strip exiting the low tension uncoiler is rapidly quenched (e.g., at a rate equal to or greater than 30, 50, 100, or 200 ℃/s) through a plurality of quenching zones. The coolant may be removed, for example, by using an air knife and/or an ultra-soft wiper. In some cases, the steam collected from the earlier quench zones may be repurposed to provide humid air to the metal strip at regions where the temperature of the metal strip is at or below the leidenfrost point. The cooled metal strip may be passed through a tensioner (bridge) to increase the tension in the metal strip before it is optionally lubricated and then rewound or otherwise further processed.

In metal production, a continuous casting process or rolling process (e.g., hot rolling) may produce a coiled product, such as a coiled metal strip. As disclosed herein, the term metal strip includes any suitable thickness of metal article that can be wound, such as a sheet of metal (sheet) or a metal sauter plate (sheet). The metal strip may have any suitable length or width. In some cases, certain aspects of the present disclosure may be applicable to metal strip products that do not have to be wound, but in some cases, certain aspects of the present disclosure may be particularly applicable to metal coils. The metal coil may comprise a wound metal strip.

As used herein, flake generally refers to aluminum products having a thickness of less than about 4 mm. For example, the sheet can have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, or less than about 0.3 mm (e.g., about 0.2 mm).

As used herein, terms such as "cast metal product," "cast aluminum alloy product," and the like are interchangeable and refer to a product produced by direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (including, for example, by using a twin belt caster, twin roll caster, block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method.

As used herein, "room temperature" can mean a temperature of about 15 ℃ to about 30 ℃, e.g., about 15 ℃, about 16 ℃, about 17 ℃, about 18 ℃, about 19 ℃, about 20 ℃, about 21 ℃, about 22 ℃, about 23 ℃, about 24 ℃, about 25 ℃, about 26 ℃, about 27 ℃, about 28 ℃, about 29 ℃, or about 30 ℃. As used herein, the meaning of "ambient conditions" may include a temperature of about room temperature, a relative humidity of about 20% to about 100%, and a gas pressure of about 975 millibars (mbar) to about 1050 mbar. For example, the relative humidity may be about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, or a, About 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%, or any value therebetween. For example, the gas pressure may be about 975 mbar, about 980 mbar, about 985 mbar, about 990 mbar, about 995 mbar, about 1000 mbar, about 1005 mbar, about 1010 mbar, about 1015 mbar, about 1020 mbar, about 1025 mbar, about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or any value therebetween.

While certain aspects of the present disclosure may be applicable to any type of metal, certain aspects of the present disclosure may be particularly applicable to aluminum. In this specification, references to alloys are identified by AA numbers and other related names, such as "series" or "7 xxx". To understand the numbering nomenclature system most commonly used to name and identify Aluminum and its Alloys, see "International Alloy Designations and Chemical Compositions Limits for Wurough Aluminum and Wurough Aluminum Alloys" or "Registration Record of Aluminum Association Alloys and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Alloys", both published by the American Aluminum industry Association.

Certain aspects of the present disclosure are particularly applicable to aluminum alloys of the 2xxx, 6xxx, 7xxx, or 8xxx series, although other alloys may also be used. When certain aluminum alloys are produced, the alloying elements form precipitates. In the case of some alloys (e.g., 2xxx, 6xxx, 7xxx, or 8xxx series alloys), significant precipitates are particularly formed when the aluminum alloy is cooled from an elevated temperature, such as to room temperature. These large precipitates do not dissolve well in the aluminum product, which is difficult or impossible to correct, and can lead to undesirable mechanical properties. For example, in 6xxx series aluminum alloys, cooling from elevated temperatures to room temperature at conventional rates may result in the formation of large Mg2Si precipitates, which may be detrimental to the desired metallographic structure of the aluminum product. These problems are particularly prevalent when cooling from a temperature above the metal recrystallization temperature (such as during an annealing or homogenization process) to room temperature. However, if the metal article can be cooled sufficiently quickly as disclosed herein, dissolved elements that would otherwise form precipitates can remain in a supersaturated solid solution up to room temperature.

In the homogenization step, the metal product described herein may be heated to a temperature in the range of about 400 ℃ to about 600 ℃. For example, the product may be heated to a temperature of about 400 ℃, about 410 ℃, about 420 ℃, about 430 ℃, about 440 ℃, about 450 ℃, about 460 ℃, about 470 ℃, about 480 ℃, about 490 ℃ or about 500 ℃. The product is then soaked (i.e., held at the indicated temperature) for a period of time. In some examples, the total time of the homogenization step (including the heating and soaking stages) may be as long as 24 hours. For example, the product may be heated up to 500 ℃ and soaked, the total time of the homogenization step being up to 18 hours. Optionally, a homogenization step, the product may be heated to less than 490 ℃ and soaked for a total time of up to 18 hours. In some cases, the homogenization step includes multiple processes. In some non-limiting examples, the homogenizing step includes heating the product to a first temperature for a first period of time, followed by heating to a second temperature for a second period of time. For example, the product may be heated to about 465 ℃ for about 3.5 hours, and then heated to about 480 ℃ for about 6 hours.

After the homogenization step, a hot rolling step may be performed. The homogenized product may be cooled to a temperature between 300 ℃ and 520 ℃ before hot rolling is started. For example, the homogenized product may be cooled to a temperature between 325 ℃ and 425 ℃ or between 350 ℃ and 400 ℃. The product may then be hot rolled at a temperature between 300 ℃ and 450 ℃ to form a hot rolled plate, hot rolled sauter plate or hot rolled sheet of a gauge between 3 mm and 200 mm (e.g. 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm or any value therebetween).

Optionally, the cast product may be a continuous cast product that may be allowed to cool to a temperature between 300 ℃ and 520 ℃. For example, the continuously cast product may be allowed to cool to a temperature between 325 ℃ and 425 ℃ or between 350 ℃ and 400 ℃. The continuously cast product may then be hot rolled at a temperature between 300 ℃ and 450 ℃ to form a hot rolled plate, hot rolled sauter plate or hot rolled sheet of a gauge between 3 mm and 200 mm (e.g. 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm or any value therebetween). During hot rolling, the temperature and other operating parameters may be controlled such that the temperature of the hot rolled intermediate product upon exiting the hot rolling mill does not exceed 470 ℃, does not exceed 450 ℃, does not exceed 440 ℃, or does not exceed 430 ℃.

The sheet, sauter board or foil can then be cold rolled into a foil using conventional cold rolling mills and cold rolling techniques. The gauge of the cold rolled sheet may be between about 0.5 to 10 mm, for example between about 0.7 to 6.5 mm. Optionally, the gauge of the cold rolled sheet may be 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm. Cold rolling may be performed to produce a final gauge thickness representing a gauge reduction of up to 85% (e.g., a reduction of up to 10%, up to 20%, up to 30%, up to 40%, up to 50%, up to 60%, up to 70%, up to 80%, or up to 85%). Optionally, an intermediate annealing step may be performed during the cold rolling step. The intermediate annealing step can be performed at a temperature of about 300 ℃ to about 450 ℃ (e.g., about 310 ℃, about 320 ℃, about 330 ℃, about 340 ℃, about 350 ℃, about 360 ℃, about 370 ℃, about 380 ℃, about 390 ℃, about 400 ℃, about 410 ℃, about 420 ℃, about 430 ℃, about 440 ℃, or about 450 ℃). In some cases, the intermediate annealing step includes multiple processes. In some non-limiting examples, the intermediate annealing step includes heating the plate, sauter plate, or sheet to a first temperature for a first period of time, followed by heating to a second temperature for a second period of time. For example, the board, sauter board, or sheet may be heated to about 410 ℃ for about 1 hour, and then heated to about 330 ℃ for about 2 hours.

Subsequently, the board, sauter board, or sheet may be subjected to a solution heat treatment step. The solution heat treatment step may be any conventional treatment of the flakes that results in solutionizing of the soluble particles. The plate, sauter plate, or sheet can be heated to a Peak Metal Temperature (PMT) of up to 590 ℃ (e.g., 400 ℃ to 590 ℃) and soaked at that temperature for a period of time. For example, the board, sauter board, or sheet can be soaked at 480 ℃ for up to 30 minutes (e.g., 0 second, 60 seconds, 75 seconds, 90 seconds, 5 minutes, 10 minutes, 20 minutes, 25 minutes, or 30 minutes). After heating and soaking, the plate, sauter plate or sheet is rapidly cooled to a temperature between 500 and 200 ℃ at a rate greater than 200 ℃/s. In one example, the plate, sauter plate, or flake has a quench rate greater than 200 ℃/sec at a temperature between 450 ℃ and 200 ℃. Optionally, the cooling rate may be faster in other cases. In some cases, quenching may be performed using a rapid quench production line as disclosed herein.

After quenching, the board, sauter board, or sheet may optionally be subjected to a pre-aging treatment by re-heating the board, sauter board, or sheet prior to winding. The pre-aging treatment may be carried out at a temperature of about 70 ℃ to about 125 ℃ for a period of up to 6 hours. For example, the pre-aging treatment may be performed at a temperature of about 70 ℃, about 75 ℃, about 80 ℃, about 85 ℃, about 90 ℃, about 95 ℃, about 100 ℃, about 105 ℃, about 110 ℃, about 115 ℃, about 120 ℃ or about 125 ℃. Optionally, the pre-aging treatment may be performed for about 30 minutes, about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, or about 6 hours. The pre-aging treatment may be performed by passing the board, sauter board, or sheet through a heating device such as a device that emits radiant heat, convection heat, induction heat, infrared heat, or the like.

The cast products described herein may also be used to make products in the form of slabs or other suitable products. For example, a plate comprising a product as described herein may be prepared by processing an ingot in a homogenization step or casting the product in a continuous caster, followed by a hot rolling step. In the hot rolling step, the cast product may be hot rolled to a gauge of 200 mm thickness or less (e.g., about 10 mm to about 200 mm). For example, the cast product may be hot rolled into a plate having a final gauge thickness of about 10 mm to about 175 mm, about 15 mm to about 150 mm, about 20 mm to about 125 mm, about 25 mm to about 100 mm, about 30 mm to about 75 mm, or about 35 mm to about 50 mm.

In some cases, it may be desirable to store the hot metal strip in the form of a metal coil (e.g., at a temperature equal to or above the recrystallization temperature of the metal). Such hot metal coils may be the result of a continuous casting process or a rolling process (e.g., from a continuously cast or DC cast product). The coil format may be used to store longer lengths of metal strip in an efficient manner. Rather than passing a long length of metal strip through a CASH line or other similar processing line having a longer length furnace and cooling zone, individual metal coils may be placed in the furnace and held at a desired temperature for a desired duration to achieve a desired heat treatment effect. For example, an aluminum coil may be held in a furnace at about 350 ℃ to 400 ℃ for a duration of time to anneal the metal strip.

Although hot metal coils can be used to store long lengths of metal strip with a relatively small footprint, the hot metal coils must be handled carefully. Whenever the metal strip is above its recrystallization temperature, there is a risk that undue pressure, tension, mechanical contact, or other forces may damage the metal strip, requiring some or all of the metal strip to be scrapped. For example, excessive tension in unwinding a hot metal coil can cause the metal strip to crack, deform, and/or surface damage. Therefore, handling hot metal coils is particularly difficult. While it may be desirable to store the metal strip as a hot coil at certain times (e.g., during heat treatment such as annealing or homogenization), it may be desirable to store the metal strip as a warm or cold coil at other times (e.g., to facilitate handling of the metal strip, such as using a forklift or other common factory equipment). In some cases, certain equipment (e.g., hot rolling mills) require sufficient back tension to operate, which may be higher than the hot metal strip can withstand. In such cases, it may be necessary to cool the hot metal coil to a sufficiently low temperature so that it can be fed into the required equipment. As disclosed herein, the terms warm and cold refer to temperatures below the recrystallization point of the metal.

Traditionally, the hot metal coil can be cooled by: the hot coil is placed at ambient or near ambient temperature, or air is forced through the coil, allowing the hot coil to cool down over several hours. In some cases, attempts have been made to spray the hot metal coil with a fluid (e.g. rolling oil), but still several hours are required to achieve the required cooling temperature, are not environmentally friendly, are very expensive, and immerse the coil in rolling oil, which limits the next operation to cold rolling mills only. According to certain aspects of the present disclosure, a rapid quenching system may cool a hot metal coil into a warm or cold metal coil in a short period of time (e.g., in a matter of minutes), in a more environmentally friendly manner, at a lower cost, and with little or no residual coolant on the metal strip.

In accordance with certain aspects of the present disclosure, a low tension uncoiler capable of safely uncoiling a hot coil is disclosed. While conventional winders use tension to ensure proper pay-off of the metal strip from the coil (pay-off), low tension unwinders use the natural pull of gravity to urge the metal strip away from the rest of the coil.

In addition, non-contact compacting devices are used to apply sufficient force through the metal strip and toward the coil to help control the proper pay out of the metal strip. As used herein, the term non-contact refers to non-mechanical contact or lack of physical contact between a metal strip and another structure. For example, the non-contacting pinch rollers may take the form of a magnetic rotor or a set of electromagnets that generate a varying magnetic field across the metal strip that induces a force on the metal strip by lenz's law without contacting the metal strip. In another example, the non-contact compaction device may take the form of one or more nozzles designed to blow hot air (e.g., hot enough to avoid quenching the metal strip) against the metal strip to control the metal strip being paid out from the remainder of the coil. The one or more nozzles do not contact the metal strip but direct fluid toward the metal strip.

In some cases, the non-contacting pinch roller may be a magnetic rotor with alternating poles oriented in a herringbone pattern such that the total magnetic flux through the metal strip is constant or nearly constant at any point in time. This herringbone pattern can produce a uniform force on the metal strip and avoid fluctuations in tension.

In some cases, the non-contacting pinch roller may be positioned at the pay-out point (e.g., the point at which the metal strip separates from the remainder of the metal coil), or may be positioned within 5 °, 10 °, 15 °, or 20 ° of the pay-out point.

As the metal strip is paid out from the rest of the coil, the curvature of the metal strip being paid out may be measured (e.g., by a distance measuring device or machine vision) and used to control the pay out rate of the coil.

In some cases, the unwinder may be maintained at a particular temperature, such as by using insulation or additional heating elements. By avoiding a temperature drop of the hot coil itself, the subsequent quenching step can be performed more accurately, since the temperature of the metal strip entering the quenching zone will be relatively stable. In some cases, a stable starting temperature for the quenching process may optionally be achieved by using an additional heating element arranged downstream of the uncoiler, which heating element may heat the metal strip to a target temperature, irrespective of fluctuations in the initial temperature of the metal strip. Such additional heating elements may take any suitable form, such as radiant, convective, infrared, flame or magnetic heating elements. In some cases, such additional heating elements may take the form of rotating magnets that are disposed adjacent to the metal strip and rotate at a sufficient speed to increase the temperature in the metal strip without contacting the metal strip. In some cases, the non-contact compaction device may work in conjunction with one or more additional heating elements to bring the temperature of the metal strip to a target temperature. In some cases, when using additional heating elements as magnetic rotors or a set of electromagnets, cold spots near the edges of the metal strip can be avoided by introducing additional heat at these cold spots before or after passing the additional heating elements. In such a case, a non-contacting hold-down device in the form of a pair of magnetic rotors positioned adjacent the metal strip at a location just before the edges of the metal strip may be used to introduce this additional heat to avoid cold spots when the metal strip passes over additional heating elements as magnetic rotors.

In some cases, a magnetic rotor, an electromagnet, and/or an air jet may be used to induce a wave (e.g., a sine wave) to stabilize the sheet.

The expanded metal strip may pass through a set of quenching zones (e.g., one or more quenching zones or two or more quenching zones). Each quenching zone may include a set of showerheads (e.g., an upper showerhead and a lower showerhead) configured to deliver a coolant to the metal strip. As used herein, a showerhead may include a single nozzle, multiple nozzles, or any other suitable configuration. The coolant may comprise any suitable coolant, such as water, oil, air, or leidenfrost-free fluid. The showerhead may be sized to deliver a coolant to the metal strip to reduce the temperature of the metal strip at a rate of 100 ℃/s or 200 ℃/s or at least 100 ℃/s or 200 ℃/s. The set of quench zones may begin adjacent to the payout point as the metal strip is flat falling, or may begin spaced from the payout point after the metal strip has been flat falling. In some cases, the showerheads of one or more of the quenching zones may be coupled to actuators to control their relative positions with respect to the metal strip in order to maintain a desired spacing between the metal strip and the showerheads.

In some cases, the parameters of the set of quench zones may be adjusted to achieve a desired quench rate optimized for a particular alloy. In some cases, automatic or manual identification of the incoming alloy may be used to pre-adjust the parameters of the set of quench zones.

In some cases, the vapor recovery module may collect vapor from one or more quenching zones (e.g., the first one or more quenching zones) in the set of quenching zones and direct the vapor to the metal strip at a further downstream point. It may be particularly advantageous to direct steam towards the metal strip at a location where the metal strip has cooled sufficiently to reach a temperature equal to or below the leidenfrost point, but this need not always be the case. The vapor recovery module may optionally include a blower (e.g., a fan) or other equipment necessary to facilitate the redirection of the collected vapor. The presence of this humid air around the metal strip after the leidenfrost point avoids condensation on the metal strip and has a greater heat capacity than dry air to extract heat from the metal strip. Thus, the use of recaptured steam may provide a consistent environment for heat extraction through and/or after the leidenfrost point. This consistent wet environment has been found to preserve the flatness of the cooled metal strip. In some cases, however, the steam recovery module may collect steam and/or redirect the steam away from the metal coil to help prevent contamination of the metal strip still on the metal coil, with or without redirecting the steam to the metal strip at a further downstream point.

Above the leidenfrost point, it is not important to keep the surface of the metal strip dry due to the rate at which the coolant boils. Below the leidenfrost point, however, it may be important to remove residual coolant from the metal strip. Thus, an air knife may be used to wipe coolant off the top of the metal strip (e.g., away from the centerline and over the edges of the metal strip). In some cases, a scraper may be used to remove excess coolant. Under the metal strip, an eraser, such as ultra-soft, may be used. The ultra-soft eraser may include a number of actuators designed to change the shape of the ultra-soft eraser to match the wave shape of the metal strip. In some cases, a lubricating spray (e.g., an oil spray) may be applied to the metal strip before reaching the eraser.

After the metal strip has been rapidly quenched and excess coolant removed, the metal strip may be passed through a device to add tension back into the metal strip, such as a tensioner. The tensioner may comprise a set of rollers around which the metal belt is wound to maintain tension in the downstream direction. Since the rapid quenching system is particularly suited for processing individual hot metal coils, it is beneficial to use tensioning members that are easy to traverse, such as tensioning members having lower and/or inner rollers that can be moved away from the upper and/or outer rollers to a traversing position for traversing and then moved back to an operating position to introduce tension into the metal strip.

After the tensioning roll, the metal strip may optionally pass through a lubricator and then bypass the deflection roll before entering the required downstream equipment parts (e.g. winder). In some cases, the deflection rollers may measure the flatness of the metal strip (e.g., flatness measurement rollers). In some cases, this measured flatness may be used to provide feedback to the set of quench zones in order to control the flatness of the metal strip.

In some cases, the rapid quenching systems disclosed herein may facilitate production of fully solutionized metal products without the use of a CASH line, thereby saving time, expense, and capital expenditure.

The aluminum alloy products described herein may be used in automotive applications and other transportation applications, including aerospace and railroad applications. For example, the disclosed aluminum alloy products can be used to make automotive structural components, such as bumpers, side sills, roof beams, cross beams, pillar reinforcements (e.g., a, B, and C pillars), inner panels, outer panels, side panels, inner covers, outer covers, or trunk lids. The aluminum alloy products and methods described herein may also be used in aerospace or railway vehicle applications to make, for example, exterior and interior panels.

The aluminum alloy products and methods described herein may also be used in electronic applications. For example, the aluminum alloy products and methods described herein can be used to prepare housings for electronic devices, including mobile phones and tablet computers. In some examples, the aluminum alloy products may be used to prepare housings for mobile phones (e.g., smart phones), tablet chassis, and other portable electronic devices.

All ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of "1 to 10" should be considered to include any and all subranges between (and including) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g., 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10. Unless otherwise indicated, the expression "at most" when referring to a compositional amount of an element means that the element is optional and includes zero compositional percentage of the particular element. All compositional percentages are weight percentages (wt%), unless otherwise indicated.

As used herein, "a" and "the" include both singular and plural referents unless the context clearly dictates otherwise.

These illustrative examples are given to introduce the reader to the general subject matter discussed herein and are not intended to limit the scope of the disclosed concepts. The following sections describe various additional features and examples with reference to the drawings, in which like numerals represent like elements, and the directional descriptions are used to describe the illustrative embodiments but, like the illustrative embodiments, should not be used to limit the present disclosure. Elements included in the description herein may not be drawn to scale.

Fig. 1 is a schematic side view of a system 100 for rapidly quenching and rewinding a hot metal coil 104 in accordance with certain aspects of the present disclosure. The hot metal coil 104 includes a metal strip 124 at an elevated temperature (e.g., at a temperature equal to or greater than the recrystallization temperature of the metal strip 124).

The metal coil 104 may be unwound by an unwinder 102. An uncoiler 102 may uncoil a hot metal coil 104 in an uncoiling direction 106. The noncontact hold-down device 108 may apply a slight force to facilitate controlled pay-out of the metal strip 124 from the remainder of the coil 104. As depicted in fig. 1, the noncontact compaction device 108 is a noncontact compaction roller that rotates in a direction 110 to apply a slight downstream tension in a metal belt 124.

The metal strip 124 may fall due to gravity, naturally away from the rest of the coil 104, thereby assuming a curvature. The curvature may be monitored by sensors 194, such as distance sensors and/or cameras (e.g., sensing curvature via machine vision). The sensor 194 may be coupled to the controller 192. The controller 192 may use the curvature measurements to adjust the system 100, such as by adjusting the payout rate of the unwinder 102. In some cases, adjusting may include manipulating the position of the showerheads 114, 116 of one or more of the set of quench zones 112.

In some cases, the uncoiler 102 may include insulation surrounding at least a portion of the metal coil 104 to retain heat within the metal coil 104. In some cases, the uncoiler 102 may include a heater, such as a heated mandrel, sufficient to maintain the temperature of the metal strip 124 while the metal strip 124 is in the metal coil 104.

The expanded metal strip 124 may pass through a set of quench zones 112. Each quench zone of the set of quench zones can include an upper showerhead 114 and a lower showerhead 116. Each showerhead 114, 116 may itself include one or more jets through which coolant is directed toward the metal strip. The rate of coolant flow may be controlled, for example, via controller 192. The rate of coolant flow may be sufficient to reduce the temperature of metal strip 124 by at least 100 ℃/s or 200 ℃/s.

After passing through the set of quench zones 112, the metal strip may pass through an air knife 118 that blows excess coolant off the top of the metal strip 124. In some cases, an optional scraper 122 may be used to further remove excess coolant. In some cases, an eraser 120 may be used to remove excess coolant from the bottom of the metal strip 124. In some cases, the eraser 120 is an ultra-soft eraser.

After the coolant has been removed from the metal belt 124, the metal belt 124 may pass through a tensioning zone 126. In the tension zone 126, the metal strip 124 may be wrapped around upper and lower tension rollers 130, 132 to impart a desired amount of tension to the metal strip 124 downstream of the tension zone 126 without imparting additional tension to the metal strip 124 upstream of the tension zone 126. In some cases, a device other than the tension rollers 130, 132 or in addition to the tension rollers 130, 132 may be used to impart the necessary tension on the metal strip 124. In some cases, the tensioning region 126 may include an easily walkable tensioning member. As depicted in fig. 1, the tensioning zone 126 includes two tensioning arms 128, each of which couples an upper tensioning roller 130 to a lower tensioning roller 132. The tensioning arm 128 is in the operating position in fig. 1. To pass the metal belt 124 through the tensioning zone 126, the tensioning arm 128 may be pivoted about the upper tensioning roller 130 such that the lower tensioning roller 132 is located above the upper tensioning roller 130. The metal belt 124 may then easily pass between the upper and lower tension rollers 130, 132 (e.g., the metal belt 124 may pass over the upper tension roller 130 and under the lower tension roller 132). Then, to move the tensioner arm 128 back to the operating position, the tensioner arm 128 may again pivot about the upper tensioner roller 130 until the lower tensioner roller 132 fully engages the metal belt 124, as depicted in fig. 1.

In some cases, metal strip 124 may optionally pass through a lubricator 134 to apply a lubricant to metal strip 124, such as to lubricate metal strip 124 prior to winding metal strip 124.

In some cases, the metal belt 124 may bypass the deflection roller 136. The deflection roller 136 may redirect the metal strip 124 for proper winding by the winder 134. In some cases, the deflection roller 136 may measure the flatness of the metal strip. In such cases, the deflection rollers 136 may be coupled to the controller 192 to facilitate feedback control of the set of quench zones 112 based on the flatness measured at the deflection rollers 136. The deflection roller 136 may be a flatness measuring roller.

As depicted in fig. 1, the metal strip 124 is wound into a metal coil 140 by a winder 138 after being cooled and after applying tension. The coil 140 is a warm or cold coil having a temperature below the recrystallization temperature of the metal strip 124. In some cases, the metal coil 140 is at room temperature. In some cases, the metal coil 140 (e.g., the quenched metal strip 124) is at a temperature suitable for warm or cold rolling.

Fig. 2 is a schematic side view of a system 200 for rapidly quenching a hot metal coil 204 for further rolling according to certain aspects of the present disclosure. System 200 may be similar to system 100, but with a number of different elements and configurations. Certain aspects and features of system 200 may be used in system 100 where appropriate, and certain aspects and features of system 100 may be used in system 200 where appropriate. The hot metal coil 204 includes a metal strip 224 at an elevated temperature (e.g., at a temperature equal to or greater than the recrystallization temperature of the metal strip 224).

The metal coil 204 may be unwound by an unwinder 202. An uncoiler 202 may uncoil a hot metal coil 204 in an uncoiling direction 206. The non-contact compaction device 208 may apply a slight force to facilitate controlled pay out of the metal strip 224 from the remainder of the roll 204. As depicted in fig. 2, the noncontact compaction device 208 is a noncontact compaction roller that rotates in direction 210 to apply a slight downstream tension in the metal belt 224.

The metal strip 224 may fall due to gravity, naturally away from the rest of the coil 204, thereby assuming some curvature. The curvature may be monitored by a sensor as disclosed with reference to the system 100 of fig. 1. The controller may be used to make adjustments to the system 200 as disclosed with reference to the system 100 of fig. 1.

In some cases, the uncoiler 202 may include insulation surrounding at least a portion of the metal coil 204 to retain heat within the metal coil 204. In some cases, the uncoiler 202 may include a heater, such as a heated mandrel, sufficient to maintain the temperature of the metal strip 224 while the metal strip 224 is in the metal coil 204.

The expanded metal strip 224 may pass through a set of preheaters 246 before passing through a set of quench zones 212. As depicted in fig. 2, the pre-heater 246 is a magnetic rotor that rotates and generates a varying magnetic field through the metal strip 224 sufficient to raise the temperature of the metal strip 224 to a target temperature. In some cases, however, other types of pre-heaters 246 may be used, such as direct fired heaters, infrared heaters, hot air blowers, or other heaters.

After being heated to a consistent target temperature, the metal strip 224 may be passed through the set of quench zones 212. Each quench zone of the set of quench zones can include an upper showerhead 214 and a lower showerhead 216. Each showerhead 214, 216 may itself include one or more orifices through which coolant is directed toward the metal strip. The rate of coolant flow can be controlled. The rate of coolant flow may be sufficient to reduce the temperature of metal strip 224 by at least 100 ℃/s or 200 ℃/s.

In some cases, a vapor recovery module 242 may be positioned adjacent to the set of quenching zones 212 to capture vapor from an area near one or more quenching zones in the set of quenching zones and redirect the vapor toward the metal strip 224 at a further downstream location. As depicted in fig. 2, the steam recovery module 242 includes a duct system configured to capture steam and redirect the steam toward the metal strip 224, although this need not always be the case. For example, in some cases, the vapor recovery module 242 may take the vapor out of the metal strip 224 with the blower and return toward the metal strip 224. In some cases, however, the vapor recovery module 242 may collect and/or redirect the vapor away from the metal coil 204 to help prevent contamination of the metal strip 224 that is still on the metal coil 204.

After passing through the set of quench zones 212, the metal strip 224 may pass through a gas knife 218 that blows excess coolant off the top of the metal strip 224. In some cases, an optional scraper 222 may be used to further remove excess coolant. In some cases, the wiper 220 may be used to remove excess coolant from the bottom of the metal strip 224. In some cases, the eraser 220 may be an ultra-soft eraser.

After the coolant has been removed from the metal strip 224, the metal strip 224 may pass through a tensioning zone 226. In the tension zone 226, the metal strip 224 may be wound over an outer tension roller 230 and an inner tension roller 232 to impart a desired amount of tension to the metal strip 224 downstream of the tension zone 226 without imparting additional tension to the metal strip 224 upstream of the tension zone 226. In some cases, a device other than the tension rollers 230, 232 may be used in addition to the tension rollers 230, 232 to impart the necessary tension on the metal strip 224. As depicted in fig. 2, the tension rollers 230, 232 are in an operating position. To facilitate passage through the tension zone 226, the inner tension roller 232 may be raised and the metal belt 224 may be passed over the outer tension roller 230 and under the inner tension roller 232. The inner tension roller 232 may then be moved back down to the position shown in fig. 2 to engage the metal strip 224 and into the operating position.

In some cases, metal strip 224 may optionally pass through a lubricator 234 to apply a lubricant to metal strip 224 to lubricate metal strip 224 prior to rolling metal strip 224.

In some cases, the metal strip 224 may be directed to downstream equipment, such as a roll set 224 of a rolling mill. The downstream equipment may be any suitable downstream equipment, such as downstream equipment requiring an amount of back tension greater than the yield strength of the metal strip 224 at the temperature of the hot coil 204, or downstream equipment requiring the metal strip 224 to be at a temperature lower than the temperature of the hot coil 204. Thus, the system 200 may enable the hot roll 204 to be fed into downstream equipment that previously could not be used with the hot roll 204.

As depicted in fig. 2, the metal strip 224 entering the downstream equipment is at a warm or cold temperature, such as a temperature below the recrystallization temperature of the metal strip 224. In some cases, metal coil 240 is at room temperature. In some cases, the metal strip 224 entering the downstream equipment is at a temperature suitable for warm or cold rolling.

Fig. 3 is a schematic block diagram of a rapid quench production line 300 in accordance with certain aspects of the present disclosure. The rapid quench line 300 may be the systems 100, 200 of fig. 1, 2. From left to right as depicted in fig. 3, the metal strip 324 moves downstream through the rapid quench line 300.

The uncoiler 302 may receive a hot metal coil (e.g., a coil of metal at or above the recrystallization temperature) and uncoil the metal strip 324 from the hot coil at a low tension. The uncoiler 302 may pay out the metal strip 324 by gravity. In some cases, the uncoiler 302 may include a non-contact compaction device 308 adapted to apply a force to the metal coil to facilitate the uncoiling of the metal strip 324.

An optional non-contact heater 346 may be positioned downstream of the unwinder 302. Non-contact heater 346 (e.g., a pre-heater such as pre-heater 246 of fig. 2) may be any suitable device for heating metal strip 324 prior to quenching, such as a magnetic rotor heater. The magnetic rotor heater may include a set of permanent magnets disposed on the rotor that may cause the temperature on the adjacent metal strips to increase as the rotor rotates.

A set of quench zones 312 may be positioned downstream of the uncoiler 302 and optional non-contact heater 346. Each quench zone may include one or more showerheads positioned to distribute coolant over the metal strip 324. In some cases, optional vapor recovery modules 342 may be positioned to collect vapor from one or more of the quenching zones in the set of quenching zones and redirect the vapor toward the metal strip 324 to facilitate cooling the metal strip 324, particularly when the temperature of the metal strip 324 is at or below the leidenfrost point.

The coolant removal zone 318 may be positioned downstream of the set of quench zones. The coolant removal zone 318 may include any device suitable for removing coolant from the metal strip 324. In some cases, the coolant removal zone 318 can include one or more air knives. In some cases, coolant removal zone 318 may include one or more squeegees. In some cases, the coolant removal zone 318 may include one or more erasers (e.g., ultra-soft erasers).

The tensioning zone 326 may be positioned downstream of the coolant removal zone 318. The tensioning zone 326 may include a set of tensioning rollers around which the metal belt 324 may be partially wrapped to achieve downstream tension in the metal belt 324 (e.g., tension downstream of the tensioning zone 326). In some cases, the tensioning zone 326 may include an easily threaded tensioning roller.

In some cases, an optional lubricator 334 may be positioned downstream of the tensioning zone 326 to lubricate the metal strip before it reaches the downstream equipment 338.

The metal strip 324 may pass to downstream equipment 338 for further processing or storage. In some cases, the downstream apparatus 338 may include a winder. In some cases, the downstream equipment 338 may include other equipment, such as warm or cold rolling mills. By the time the metal strip 324 reaches the downstream apparatus 338, the metal strip will have cooled to a temperature below the recrystallization point and will have tension imparted on it (e.g., greater than the tension appropriate for the hot coil at the uncoiler 302).

Fig. 4 is a combined schematic block diagram 400 and temperature profile 401 depicting the relative temperature of a metal strip 424 passing through a rapid quench line in accordance with certain aspects of the present disclosure. From left to right as depicted in fig. 4, the metal strip 424 moves downstream through the rapid quench line. The block diagram 400 may be an illustration of the rapid quench production line 300 of fig. 3. The temperature profile 401 is a relative profile for illustrative purposes only and is not intended to be to scale. The block diagram 400 and the temperature profile 401 are vertically aligned to depict the approximate relative temperature of the metal strip 424 as it passes through the components of the rapid quench line depicted in the block diagram 400.

At the uncoiler 402, the metal strip 424 may have a temperature that is considered hot, such as a temperature equal to or above the recrystallization temperature 457 of the metal strip 424. In some cases, the unwinder 402 may receive hot rolls at various initial temperatures 450. In some cases, integrated heating and/or insulation in the uncoiler 402 may help maintain the initial temperature 450 of the metal strip 424.

In some cases, the optional non-contact heater 446 may impart additional heating designed to raise the temperature of the metal strip 424 to the target temperature 456, regardless of the initial temperature 450 of the hot web. In some cases, non-contact compaction device 408 may impart an amount of heat into metal strip 424, although this is not necessarily so.

Within the set of quench zones 412, a number of quench zones may be used to rapidly quench the metal strip 424. As depicted in fig. 4, four quench zones 458, 460, 462, 464 are shown, but any number of zones may be used. In some cases, when the optional vapor recovery module 442 is used, the vapor recovery module 442 can collect vapor from the upstream quenching zone(s), such as the first quenching zone 458 and the second quenching zone 460, and redirect the vapor and/or humid air toward the metal strip 424 at a location downstream of where the vapor is collected. In some cases, the vapor recovery modules 442 may redirect the vapor toward the metal strip 424 before, during, or after subsequent quenching zones (e.g., the third and fourth quenching zones 462, 464). In some cases, the vapor recovery module 442 may redirect vapor toward the metal belt 424 at a location 468 where the metal belt 424 is about to, is currently, or has fallen below the leidenfrost point 470.

After the set of quench zones 412, the temperature of the metal strip 424 may be a warm or cold temperature. The temperature of the metal strip 424 may not vary significantly after the set of quench zones 412, such as when passing through the coolant removal zone 418, the tensioning zone 426, the optional lubricator 434, or the downstream equipment 438; in some cases the temperature of metal strip 424 may slowly approach room or ambient temperature. In some cases, the temperature of the metal strip 424 after the set of quench zones 412 may be referred to as the cooled temperature 472.

Fig. 5 is a schematic side view of a vapor recovery module 542 on a rapid quench production line 500 according to certain aspects of the present disclosure. Fig. 5 depicts a portion of a rapid quench line 500 located between an uncoiler and a tensioning zone. The rapid quench line 500 may be the rapid quench line 300 of fig. 3.

As the metal strip 524 passes from left to right in a downstream direction, the metal strip may pass through several quench zones 558, 560, 562, 564, 566. Each quench zone may include a showerhead 514 that distributes a coolant 574 onto the metal strip 524. The coolant extracts heat from the metal strip 524, particularly in the vicinity of the previous quench zone, two or several quench zones (e.g., quench zones 558, 560, 562) that will generate a significant amount of steam 576.

The vapor recovery module 542 can be positioned to capture the steam 576 and redirect the steam 576 back onto the metal belt 524. In some cases, the steam recovery module 542 may include a hood 578 for collecting the steam and a conduit system 580 for redirecting the steam toward the metal belt 524. In some cases, the steam recovery module 542 can include an optional blower 582 that facilitates moving steam 576 toward the metal belt 524 (e.g., toward an end of the conduit system 580 opposite the hood 578).

As depicted in fig. 5, the steam recovery module 542 redirects the steam 576 back onto the metal strip 524 at a location downstream of the first three quench zones 558, 560, 562 and upstream of the last two quench zones 564, 566, but need not always be so. The vapor recovery module 542 may alternatively redirect the steam 576 to the metal belt 524 at any suitable location, including upstream or downstream of where the steam 576 is collected. It has been determined, however, that it may be particularly useful to redirect the steam 576 toward the metal belt 524 at a location 568 adjacent to, at a temperature of the metal belt 524 that is at or below the leidenfrost point, and/or immediately after the location 568.

Also shown in FIG. 5 is a set of air knives 518 positioned above the metal strip 524 to direct air 584 onto the surface of the metal strip 524 to remove coolant from the metal strip 524.

Fig. 6 is a schematic top view of a non-contact pressure roller 608 including a magnetic rotor 690 in accordance with certain aspects of the present disclosure. In some cases, the non-contacting pinch roller 608 may be a magnetic rotor 690. While any suitable magnetic rotor may be used, it has been determined that a magnetic rotor 690 having a herringbone magnetic pole pattern may be particularly suitable for imparting a consistent (e.g., non-fluctuating) tension to the metal strip, thereby minimizing the risk of damaging the fragile hot coil.

The chevron pattern depicted in fig. 6 shows alternating north and south poles 686 and 688 distributed across the width and circumference of the magnet rotor 690. In some cases, the chevron pattern is configured such that for all points along the rotation of magnetic rotor 690, magnetic rotor 690 will always present the same or substantially the same magnetic flux to the metal strip. The chevron patterns may differ in overlap, gap, angle of attack, and other characteristics. In some cases, magnetic rotor 690 is configured to rotate in the direction of the herringbone pattern (e.g., from the top of the page to the bottom of the page, as depicted in fig. 6), but this need not always be the case. In some cases, other types of patterns are used to achieve consistent tension on the metal strip.

Fig. 7 is a flow chart depicting a process 700 for rapidly quenching a hot metal coil in accordance with certain aspects of the present disclosure. In some cases, the process 700 may use the system 100, 200 of fig. 1, 2 or the rapid quench production line 300 of fig. 3.

At block 702, the hot metal coil is unwound. The unwinding of the hot metal coil is performed by means of a low-tension unwinder. In some cases, unwinding the hot metal roll further comprises applying a non-contact compaction force to the metal roll by a non-contact compaction device. In some cases, unwinding the hot metal coil includes allowing the metal strip to unwind from the coil by gravity.

At optional block 706, the metal strip may be heated (e.g., preheated) to a target temperature. In some cases, preheating is not required if the hot metal coil is already at the target temperature.

At block 708, the metal strip may be rapidly quenched. The rapid quenching may include reducing the temperature of the metal strip at a rate of 100 ℃/s or 200 ℃/s or at least 100 ℃/s or 200 ℃/s. Rapid quenching may involve the use of one or more showerheads to distribute coolant to the metal strip. In some cases, rapidly quenching the metal strip at block 708 may also include one or more of optional blocks 710, 712, 714. At block 710, steam from one or more quenching zones may be collected. At block 712, the metal strip may be quenched to a temperature below the leidenfrost point. At block 714, the steam collected from block 710 may be redirected to the metal strip. In some cases, block 714 may be performed without first performing block 712. In some cases, however, block 714 is only performed after the metal strip reaches a temperature below the leidenfrost point at block 712.

In some cases, quenching the metal strip at block 708 may include receiving flatness information (e.g., from a downstream flatness measurement device, such as a deflection roll) and making adjustments to the distribution of coolant from the showerhead to achieve a desired flatness.

At block 716, the coolant is removed from the metal strip. In some cases, removing the coolant from the metal strip may include using any combination of air knives, scrapers, wipers (e.g., ultra-soft wipers), or other coolant removal devices.

At block 718, tension is applied to the metal strip. The tension applied to the metal strip at block 718 may be a downstream tension such that the tension is not transferred upward through the hot roll at the uncoiler, but rather to a downstream device. Applying tension at block 718 may include passing the metal strip through tension rollers of a tension zone to impart tension into the metal strip.

At optional block 720, lubrication may optionally be applied to the metal strip.

The metal strip may be advanced downstream to any suitable downstream equipment. In some cases, the downstream equipment may be a coiler, in which case the metal strip may be coiled at block 722. The resulting metal coil will be a warm or cold metal coil. In some cases, other downstream equipment may be used, in which case the metal strip may undergo other downstream processing, such as warm or cold rolling.

The foregoing description of embodiments, including illustrated embodiments, has been presented for the purposes of illustration and description only and is not intended to be exhaustive or limited to the precise forms disclosed. Many modifications, adaptations, and uses will be apparent to those skilled in the art.

The following provides a set of illustrative examples, including at least some illustrative examples explicitly listed as "examples," which provide additional description of various exemplary embodiments according to the concepts described herein. These examples are not meant to be mutually exclusive, exhaustive, or limiting; and the disclosure is not limited to these illustrative examples but covers all possible modifications and variations within the scope of the issued claims and their equivalents.

Example 1 is a system, comprising: a low tension unwind unit for receiving and unwinding a metal coil of metal strip; a non-contact compaction device positioned adjacent to the low tension unwind unit to provide a force on the metal strip toward a center of the metal roll during unwinding of the metal roll; a set of quenching zones for cooling the metal strip, wherein the set of quenching zones provide sufficient coolant to reduce the temperature of the metal strip at a rate of at least 100 ℃ per second; a coolant removal unit positioned downstream of the set of quench zones; and a tensioning unit positioned downstream of the coolant removal unit for increasing tension in the metal strip.

Example 2 is the system of any preceding or subsequent example, or combinations of examples, wherein the low-tension unwinding unit comprises an insulator arranged to retain heat within the wound portion of the metal coil.

Example 3 is the system of any preceding or subsequent example or example combinations, wherein the low-tension unwind unit comprises a heat source to provide heat to a wound portion of the metal roll, wherein the heat source is coupled to a controller to maintain the metal roll at or above a threshold temperature.

Example 4 is the system of any preceding or subsequent example, or combinations of examples, wherein the non-contact compaction device comprises one or more magnets to generate a varying magnetic field through the metal strip.

Example 5 is the system of any preceding or subsequent example, or combination of examples, wherein the varying magnetic field is configured to distribute the force over a width of the metal strip over time.

Example 6 is the system of any preceding or subsequent example, or combinations of examples, wherein the non-contact compaction device comprises a nozzle to blow heated air toward the metal strip.

Example 7 is a system of any preceding or subsequent example, or combination of examples, further comprising: a flatness measurement unit positioned to measure flatness of the metal strip; and a controller coupled to the flatness measurement unit and the set of quenching zones to adjust the delivery of the coolant based on the measured flatness of the metal strip.

Example 8 is the system of any preceding or subsequent example, or combination of examples, further comprising a stabilization system positioned upstream of the set of quenching zones to introduce waves into the metal strip.

Example 9 is the system of any preceding or subsequent example, or combination of examples, wherein the metal strip remains supported without mechanical contact between the metal coil and the coolant removal unit.

Example 10 is the system of any preceding or subsequent example or example combination, wherein the set of quenching zones comprises a vapor recovery module for redirecting humid air from at least one quenching zone of the set of quenching zones toward the metal strip at a location downstream of the at least one quenching zone of the set of quenching zones.

Example 11 is the system of any preceding or subsequent example or example combinations, wherein the location downstream of the at least one quenching zone in the set of quenching zones is a location where a temperature of the metal strip is equal to or below a leidenfrost point.

Example 12 is a system of any preceding or subsequent example, or combination of examples, further comprising: a pre-quench heating unit positioned downstream of the low tension unwind unit; and a controller coupled to the pre-quench heating unit to heat the metal strip to a target temperature before the metal strip enters the set of quenching zones.

Example 13 is the system of any preceding or subsequent example, or combinations of examples, wherein the non-contact compaction device is positioned to provide a force to the metal strip at or near a location where the metal strip disengages from the metal coil due to gravity.

Example 14 is a method, the method comprising: unwinding a hot metal coil using a low tension unwinder, wherein unwinding the hot metal coil comprises applying a non-contact pinch force to the hot metal coil and allowing metal strip of the hot metal coil to disengage from the metal coil; rapidly quenching the metal strip in a set of quenching zones, wherein rapidly quenching the metal strip comprises applying a coolant to the metal strip to reduce the temperature of the metal strip at a rate of at least 100 ℃ per second; removing the coolant from the metal strip; and applying a downstream tension to the metal strip.

Example 15 is the method of any preceding or subsequent example or combination of examples, further comprising maintaining an initial temperature of the hot metal coil at the low-tension uncoiler.

Example 16 is the method of any preceding or subsequent example or combination of examples, further comprising preheating the metal strip immediately prior to rapidly quenching the metal strip.

Example 17 is the method of any preceding or subsequent example or combination of examples, wherein applying the non-contact compressive force comprises generating a varying magnetic field through the metal strip.

Example 18 is the method of any preceding or subsequent example or combination of examples, wherein applying the non-contact compressive force comprises blowing heated air against the metal strip.

Example 19 is a method of any preceding or subsequent example or combination of examples, further comprising: measuring the flatness of the metal strip; and adjusting the delivery of the coolant based on the measured flatness.

Example 20 is the method of any preceding or subsequent example or combination of examples, further comprising inducing a wave in the metal strip without contacting the metal strip.

Example 21 is a method of any preceding or subsequent example or example combination, further comprising: capturing steam from at least one of the quenching zones; and redirecting the captured steam toward the metal strip.

Example 22 is the method of any preceding or subsequent example or example combinations, wherein redirecting the captured steam comprises redirecting the captured steam toward the metal strip at a location where a temperature of the metal strip is equal to or below a leidenfrost point.

Claims (22)

1. A system, comprising:

a low-tension unwinding unit for receiving and unwinding a metal coil of metal strip;

a non-contact compaction device positioned adjacent to the low tension unwind unit to provide a force on the metal strip toward a center of the metal roll during unwinding of the metal roll;

a set of quenching zones for cooling the metal strip, wherein the set of quenching zones provide sufficient coolant to reduce the temperature of the metal strip at a rate of at least 30 ℃ per second;

a coolant removal unit positioned downstream of the set of quench zones; and

a tensioning unit positioned downstream of the coolant removal unit for increasing tension in the metal strip.

2. The system of claim 1, wherein the low tension unwind unit comprises insulation arranged to retain heat within a wound portion of the metal coil.

3. The system of claim 1 or 2, wherein the low-tension unwind unit comprises a heat source for providing heat to a wound portion of the metal roll, wherein the heat source is coupled to a controller for maintaining the metal roll at or above a threshold temperature.

4. The system of any one of claims 1 to 3, wherein the non-contact compaction device comprises one or more magnets for generating a varying magnetic field through the metal strip.

5. The system of claim 4, wherein the varying magnetic field is configured to distribute the force over a width of the metal strip over time.

6. The system of any one of claims 1 to 5, wherein the non-contact compacting device comprises a nozzle for blowing heated air towards the metal strip.

7. The system of any one of claims 1 to 6, further comprising:

a flatness measurement unit positioned to measure flatness of the metal strip; and

a controller coupled to the flatness measurement unit and the set of quenching zones to adjust the delivery of the coolant based on the measured flatness of the metal strip.

8. The system of any one of claims 1 to 7, further comprising a stabilization system positioned upstream of the set of quenching zones to introduce waves into the metal strip.

9. The system of any one of claims 1 to 8, wherein the metal strip remains supported without mechanical contact between the metal coil and the coolant removal unit.

10. The system of any one of claims 1 to 9, wherein the set of quenching zones includes a vapor recovery module for redirecting humid air from at least one quenching zone of the set of quenching zones toward the metal strip at a location downstream of the at least one quenching zone of the set of quenching zones.

11. The system of any one of claims 1 to 10, wherein the location downstream of the at least one quenching zone in the set of quenching zones is a location where a temperature of the metal strip is equal to or below a leidenfrost point.

12. The system of any one of claims 1 to 11, further comprising:

a pre-quench heating unit positioned downstream of the low-tension unwind unit; and

a controller coupled to the pre-quench heating unit to heat the metal strip to a target temperature before the metal strip enters the set of quenching zones.

13. The system of any one of claims 1 to 12, wherein the non-contact compaction device is positioned to provide a force to the metal strip at or near a location where the metal strip is disengaged from the coil due to gravity.

14. A method, the method comprising:

unwinding a hot metal coil using a low tension unwinder, wherein unwinding the hot metal coil comprises applying a non-contact pinch force to the hot metal coil and allowing metal strip of the hot metal coil to disengage from the metal coil;

rapidly quenching the metal strip in a set of quenching zones, wherein rapidly quenching the metal strip comprises applying a coolant to the metal strip to reduce the temperature of the metal strip at a rate of at least 100 ℃ per second;

removing the coolant from the metal strip; and

applying a downstream tension to the metal strip.

15. The method of claim 14, further comprising maintaining an initial temperature of the hot metal coil at the low tension uncoiler.

16. The method of claim 14 or 15, further comprising preheating the metal strip immediately prior to rapidly quenching the metal strip.

17. The method of any of claims 14 to 16, wherein applying the non-contact compressive force comprises generating a varying magnetic field through the metal strip.

18. The method of any one of claims 14 to 17, wherein applying the non-contact compressive force comprises blowing heated air against the metal strip.

19. The method of any one of claims 14 to 18, further comprising:

measuring the flatness of the metal strip; and

adjusting the delivery of the coolant based on the measured flatness.

20. The method of any one of claims 14 to 19, further comprising inducing a wave in the metal strip without contacting the metal strip.

21. The method of any one of claims 14 to 20, further comprising:

capturing steam from at least one of the quenching zones; and

redirecting the captured steam toward the metal strip.

22. The method of claim 21, wherein redirecting the captured steam comprises redirecting the captured steam toward the metal strip at a location where the temperature of the metal strip is at or below the leidenfrost point.

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