Device for spraying an item with a coolant

Abstract

Device (100) for spraying an item (200) with a coolant, comprising: a nozzle body (110) with a mixing chamber (112) and with a first inlet port (112-1) for supplying a first coolant component (300-1) into the mixing chamber (112), a second inlet port (112-2) for supplying a second coolant component (300-2) into the mixing chamber (112), and with an outlet port (112-3) for discharge of a first coolant as a mixture of the first and the second coolant components (300-1, 300-2) from the mixing chamber (112); and a two-component nozzle (120) connected by line to the outlet port (112-3) of the mixing chamber (112) for spraying the material (200) with the first coolant; characterized by the fact that the nozzle body (110) next to the mixing chamber (112) has a separate coolant channel (130) with its own inlet port (130-1) for supplying the second coolant component (300-2) into the coolant channel (130) and with its own outlet port (130-2) for removing a second coolant in the form of the second coolant component (300-2) from the coolant channel (130); A single-fluid nozzle (140) connected to the outlet port (130-2) of the coolant channel is provided for spraying the goods (200) with the second coolant (300-2); a pressure adjusting device (150) is provided for adjusting the pressure of the first coolant component when supplied via the first inlet port (112-1) into the mixing chamber (112); a valve assembly (160) is provided for supplying the second coolant component (300-2) either to the second inlet port (112-2) of the mixing chamber (112) or to the inlet port (130-1) of the coolant channel (130); and a control device (170) is provided for controlling the pressure setting device (150) and / or the valve device (160) differently in a single-fluid nozzle operating state or in a two-fluid nozzle operating state.

Description

[0001] The invention relates to a device for spraying a workpiece, in particular a metallic casting product, with a coolant. The invention is particularly applicable in secondary cooling systems of various continuous casting systems, such as compact strip production (CSP) plants, vertical bending plants, vertical continuous casting plants, arc continuous casting plants, oval continuous casting plants, belt-casting technology (BCT) plants for casting molten metal onto a metal strip, horizontal casting machines for long products, or horizontal continuous casting (HCC) plants.

[0002] Secondary cooling systems in these continuous casting systems are required to allow for controlled cooling of the casting strand. Currently, these systems are equipped with either single-component or two-component secondary cooling nozzles. Both nozzle types have different characteristics. Using single-component secondary cooling nozzle technology results in lower minimum cooling rates. For example, the typical heat transfer coefficient of a single-component nozzle ranges from a minimum of 800 to a maximum of 10,000 W / m. 2 / K. In contrast, the use of a two-component secondary cooling nozzle technology results in a limit on the maximum cooling rates. A typical two-component nozzle typically exhibits a heat transfer coefficient range of a minimum of 200 to a maximum of 2,600 W / m². 2 / K on.

[0003] In modern continuous casting systems, a wider product mix necessitates the ability to provide the largest possible cooling range. This requires the secondary cooling systems to achieve both the lowest and highest possible cooling rates. Traditionally, different sizes of secondary cooling nozzles are used, distributed along the strand. Alternatively, compromises must be made regarding the achievable heat transfer ranges. In extreme cases, it may even be necessary to replace the secondary cooling nozzles for specific products. However, this requires that the upstream control loops are designed to manage the different secondary cooling nozzles with their varying limit values.

[0004] In the prior art, both single-fluid nozzles, which are operated with only one coolant or coolant component, and dual-fluid nozzles, which are operated with a mixture of a first and a second coolant component, typically a mixture of air and water, are known. Specifically, embodiments of dual-fluid nozzles are known, for example, from German patent applications DE 101 30 445 A1, DE 10 2011 080 127 A1, German utility model DE 200 10 074 U1, and international patent application WO 2013 / 017488 A1. In particular, the latter two documents disclose a device for spraying a material with a coolant according to the preamble of claim 1. Specifically, they each disclose a device with a nozzle body that has a mixing chamber, wherein the mixing chamber has a first inlet connection for supplying a first coolant component, e.g.,The known device has an air inlet, a second inlet for supplying a second coolant component, e.g., water, and an outlet for removing a first coolant as a mixture of the first and second coolant components. Furthermore, the device features a two-component nozzle connected to the outlet of the mixing chamber for spraying the material with the first coolant.

[0005] Based on this prior art, the invention aims to further develop a known device for spraying a product with a coolant in such a way that the cooling area covered by it is extended.

[0006] This problem is solved by the subject matter of claim 1. This is characterized in that the nozzle body has, in addition to the mixing chamber, a separate coolant channel with its own inlet port for supplying the second coolant component into the coolant channel and with its own outlet port for removing a second coolant in the form of the second coolant component from the coolant channel.Claim 1 is further characterized in that a single-component nozzle connected to the outlet port of the coolant channel is provided for spraying the material with the second coolant, that a pressure adjustment device is provided for adjusting the pressure of the first coolant component when supplied via the inlet port to the mixing chamber, that a valve device is provided for supplying the second coolant component either to the second inlet port of the mixing chamber or to the inlet port of the coolant channel, and that finally a control device is provided for controlling the pressure adjustment device and / or the valve device differently in a single-component nozzle operating state or in a two-component nozzle operating state.

[0007] The claimed device advantageously combines the properties of single-component secondary cooling nozzle technology with those of dual-component secondary cooling nozzle technology such that the claimed device is able to combine both the lowest cooling rates of the dual-component secondary cooling nozzle with the maximum achievable cooling rates of the single-component secondary cooling nozzle, or to cover the entire cooling rate range of both nozzles in combination. In this respect, the claimed device represents a hybrid secondary cooling nozzle that combines the unique properties of single-component and dual-component nozzles. In particular, the upper limit of the cooling effect of the dual-component nozzle is extended into the upper cooling rate range by the integrated single-component secondary cooling nozzle technology. Likewise, the missing lower cooling rate range of the single-component secondary cooling nozzle technology can be covered by the dual-component secondary cooling nozzle technology, which then takes over this function.To achieve the large cooling range, the device according to the invention has a control unit for operating the device according to the invention either in a single-fluid nozzle operating state or in a two-fluid nozzle operating state.

[0008] According to a first embodiment, the control device is configured, in the single-fluid nozzle operating state, to actuate the valve assembly such that the second coolant component is directed only to the inlet port of the coolant channel and thus to the single-fluid nozzle. The second coolant component is then not directed into the mixing zone. Similarly, the supply of the first coolant component to the mixing zone can also be completely blocked. Alternatively, however, the control device can actuate the pressure adjustment device such that the first coolant component is subjected only to a two-fluid nozzle protective pressure, which is, for example, less than 50,000 Pa. This has the advantage that the two-fluid nozzle is then protected from contamination or clogging by particles that could be splashed up from the hot material being cooled.

[0009] Furthermore, the control device is designed to actuate the pressure setting device in the two-component nozzle operating state in such a way that the first coolant component is supplied with a two-component nozzle operating pressure value, for example from a pressure range of 1 to 8 bar, and simultaneously actuate the valve device in such a way that the second coolant component is directed to the second inlet port of the mixing chamber.

[0010] The control unit of the device according to the invention is designed to realize both the single-fluid nozzle operating state and the dual-fluid nozzle operating state by suitable control of, in particular, the valve assembly and the pressure adjustment device. However, only one of the two operating states can be realized at any given time.

[0011] In one variant of the two-component nozzle operating state, the control unit controls the valve control unit in such a way that the supply of the second coolant component to the inlet port of the coolant channel is completely prevented. According to a second variant of the two-component nozzle operating state, the control unit controls the valve control unit in such a way that the supply of the second coolant component to the inlet port of the coolant channel occurs with a single-component nozzle protective flow.

[0012] This single-fluid nozzle protective flow has the same function and the same advantage as supplying the two-fluid nozzle with the first coolant component at low pressure during the single-fluid nozzle operating condition, namely to prevent clogging by splashes.

[0013] The first coolant component is, for example, air, while the second coolant component is, for example, cooling water.

[0014] If the valve assembly is structurally integrated into the nozzle body, this has the advantage that only one inlet connection for the second coolant component needs to be routed outside the nozzle body. Additionally, the control input of the valve assembly can be routed outside the nozzle body. However, this is not strictly necessary if the control input of the valve assembly is designed as a pressure switching input and connected to the supply line for the first coolant component. This connection can be located inside or outside the nozzle body.

[0015] If the control input of the valve assembly is configured as a pressure switching input and connected to the supply line for the first coolant component in the mixing chamber, this offers the advantage that switching the device according to the invention between the single-component nozzle operating state and the dual-component nozzle operating state can occur solely in response to the pressure of the first coolant component. Direct actuation of the valve assembly by the control unit is then not required.

[0016] Further advantageous embodiments of the device according to the invention are the subject of the dependent claims.

[0017] The invention is accompanied by a total of four figures, wherein Fig. 1 the device according to the invention in an overview representation; Fig. 2 the nozzle body according to the invention in a first embodiment with external valve device; Fig. 3 the nozzle body according to the invention with integrated valve device and external control; and Fig. 4 shows the nozzle body according to the invention with integrated valve device and with connection of the control input of the valve device to the supply line of a first coolant component.

[0018] The invention is described in detail below with reference to the figures mentioned, in the form of exemplary embodiments. In all figures, identical technical elements are designated by the same reference numerals.

[0019] Fig. Figure 1 shows an overall view of the device 100 according to the invention. The nozzle body 110 with its two inlet connections 112-1, 112-2 for a first and a second coolant component is visible. The nozzle body 110 is connected to a two-component nozzle 120 via a two-component nozzle tube 180 and to a single-component nozzle 140 via a single-component nozzle tube 190. The two-component nozzle 120 serves to spray a first coolant, as a mixture of the first and second coolant components 300-1, 300-2, onto a material 200 to be cooled, for example, a casting strand.

[0020] Fig. Figure 2 shows a cross-sectional view of the nozzle body 110 according to the invention. Within the nozzle body 110, the mixing chamber 112 is visible, with its first inlet port 112-1 for supplying the first coolant component, for example, air, and its second inlet port 112-2 for supplying the second coolant component, typically cooling water, into the mixing chamber 112. Alternatively, the first inlet port 112-1 can be configured to supply the second coolant component and the second inlet port 112-2 to supply the first coolant component into the mixing chamber. Furthermore, the outlet port 112-3 of the mixing chamber 112 is visible for discharge of a first coolant in the form of a mixture of the first and second coolant components, i.e., for example, an air-water mixture, from the mixing chamber 112 via the two-fluid nozzle tube 180 into the two-fluid nozzle 120.

[0021] In addition to the mixing chamber 112, the nozzle body 110 has a separate coolant channel 130 with its own inlet port 130-1 for supplying the second coolant component 300-2 into the coolant channel 130 and with its own outlet port 130-2 for discharging the second coolant component 300-2 from the coolant channel 130 via the single-component nozzle tube 190 into the single-component nozzle 140. The two-component nozzle tube 180 and the single-component nozzle tube 190 can be guided together in a sheath tube 195; the two individual nozzle tubes are then not visible from the outside.

[0022] The first coolant component 300-1 is fed to the first inlet port 112-1 of the mixing chamber 112 via a separate supply line. A pressure control device 150 is arranged in the supply line to adjust the pressure at which the first coolant component 300-1 is supplied to the mixing chamber 112. The second coolant component 300-2 is directed via a valve assembly 160, which is designed, for example, as a three-way switching valve or consists of two two-way valves, either to the second inlet port 112-2 of the mixing chamber or to the inlet port 130-1 of the separate coolant channel. Both the pressure control device 150 and the valve assembly 160 are controlled by a control unit 170, depending on whether the single-component nozzle operating state or the two-component nozzle operating state is selected by a higher-level process control system for a current casting or cooling process.In the single-fluid nozzle operating state, the valve assembly 160 is controlled by the control unit 170 such that the second coolant component 300-2 is only directed to the inlet port 130-1 of the coolant channel 130 and thus to the single-fluid nozzle 140. The supply line for the first coolant component 300-1 is typically blocked by the control unit 170. Alternatively, in the single-fluid nozzle operating state, the pressure control unit 150 can also be controlled by the control unit 170 such that the two-fluid nozzle 120 is only supplied with the first coolant component 300-1 at a two-fluid nozzle protective pressure of, for example, < 50,000 Pa.This operation of the two-fluid nozzle does not make any significant contribution to cooling the material to be cooled in the single-fluid nozzle operating state, but merely serves to prevent the air flowing out of the two-fluid nozzle 120 from clogging during the casting operation.

[0023] During the two-component nozzle operating state, the pressure adjusting device 150 is controlled by the control unit 170 such that the first coolant component 300-1 is supplied with a two-component nozzle operating pressure, for example, from a pressure range between 100,000 Pa and 800,000 Pa. Simultaneously, the valve device 160 is controlled by the control unit 170 such that the second coolant component 300-2 is directed to the second inlet port 112-2 of the mixing chamber 112. Also during the two-component nozzle operating state, the control unit 170 is configured to control the valve device 160 in a first variant such that the supply of the second coolant component 300-2 to the inlet port 130-1 of the coolant channel 130 is completely prevented.Alternatively, according to a second variant of the two-fluid nozzle operating state, the valve assembly 160 can also be controlled by the control unit 170 such that the second coolant component 300-2 is supplied to the inlet port 130-1 of the coolant channel 130 only with a single-fluid nozzle protective flow. This operation of the single-fluid nozzle 140 during the two-fluid nozzle operating state also does not provide any significant cooling benefit, but merely serves to prevent the single-fluid nozzle from becoming clogged by particles in the ambient air of the material to be cooled.

[0024] At the in Fig. In the embodiment shown in Figure 2, the pressure adjusting device 150 and the valve device 160 are each arranged outside the nozzle body 110.

[0025] Fig. Figure 3 shows a further embodiment of the nozzle body 110, in which the valve assembly 160 is integrated into the nozzle body 110. The two lines for the second coolant component 300-2, which in the embodiment according to Fig. 2. Connecting the outputs of the valve assembly 160 to the second inlet 112-2 of the mixing chamber and the inlet 130-1 of the coolant channel, in the embodiment according to Fig. 3 is omitted because the outputs of the valve assembly 160 are directly connected to the aforementioned inlet 112-2 of the mixing chamber and the inlet 130-1 of the coolant channel. As in Fig. As can be seen in diagram 3, only the control input 164 and the input connection 162 for the second coolant component are brought to the outside. This is shown in Fig. The embodiment shown in Figure 3 offers the advantage of a compact design; the control and operation of the device according to the invention are different from the example shown in Figure 3. Fig. 2 unchanged.

[0026] Fig. 4 finally shows another embodiment, which differs from the embodiment according to Fig.3 differs in that the control input 164 of the valve assembly 160 is not externally accessible. Rather, in this embodiment, the control input 164 is designed as a pressure switching input and is connected via a branch line 166 to the supply line or the inlet port 112-1 for the first cooling component 300-1 into the mixing chamber 112. In this example, the switching of the device according to the invention between the single-fluid nozzle operating state and the dual-fluid nozzle operating state occurs solely depending on the pressure at which the first coolant component 300-1 is supplied to the mixing chamber 112 and which is present at the pressure switching input 164. If this pressure is above a predetermined threshold value, the valve assembly 160 switches to dual-fluid nozzle operation; if, on the other hand, the pressure is below the predetermined threshold value, the valve assembly 160 switches to the single-fluid nozzle operating state. Reference symbol list 100 Device 110 nozzle bodies 112 Mixing chamber 112-1 first input port 112-2 second input port 112-3 Output port 120 Two-fluid nozzle 130 Coolant channel 130-1 Input connection 130-2 Output connection 140 Single-fluid nozzle 150 pressure setting device 160 Valve assembly 164 Tax input 166 Branch line for first coolant component 162 Inlet port for second coolant component 170 Control unit 180 Two-fluid nozzle tube 190 Single-fluid nozzle tube 195 Sheathing tube 200 Good 300-1 first cooling component 300-2 second cooling component

Claims

Device (100) for spraying a product (200) with a coolant, comprising: a nozzle body (110) with a mixing chamber (112) and with a first inlet port (112-1) for supplying a first coolant component (300-1) into the mixing chamber (112), a second inlet port (112-2) for supplying a second coolant component (300-2) into the mixing chamber (112) and with an outlet port (112-3) for discharge of a first coolant as a mixture of the first and the second coolant components (300-1, 300-2) from the mixing chamber (112); and a two-component nozzle (120) connected by a line to the outlet port (112-3) of the mixing chamber (112) for spraying the product (200) with the first coolant;characterized in that the nozzle body (110) has a separate coolant channel (130) next to the mixing chamber (112) with its own inlet port (130-1) for supplying the second coolant component (300-2) into the coolant channel (130) and with its own outlet port (130-2) for discharge of a second coolant in the form of the second coolant component (300-2) from the coolant channel (130); a single-component nozzle (140) connected by a line to the outlet port (130-2) of the coolant channel is provided for spraying the material (200) with the second coolant (300-2); a pressure adjusting device (150) is provided for adjusting the pressure of the first coolant component when supplied via the first inlet port (112-1) into the mixing chamber (112);A valve assembly (160) is provided for supplying the second coolant component (300-2) either to the second inlet port (112-2) of the mixing chamber (112) or to the inlet port (130-1) of the coolant channel (130); and a control device (170) is provided for controlling the pressure control device (150) and / or the valve assembly (160) differently in a single-fluid nozzle operating condition or in a dual-fluid nozzle operating condition. Device (100) according to claim 1, characterized in that the control device (170) is configured to actuate the valve device (160) in the single-fluid nozzle operating state such that the second coolant component (300-2) is directed only to the inlet port (130-1) of the coolant channel (130) and thus to the single-fluid nozzle (140), and the pressure control device (150) - only optionally - such that the two-fluid nozzle (120) is supplied with the first coolant component (300-1) at a two-fluid nozzle protective pressure value, for example less than 50,000 Pa. Device (100) according to one of the preceding claims, characterized in that the control device (170) is configured to actuate the pressure control device (150) in the two-fluid nozzle operating state such that the first coolant component (300-1) is supplied with a two-fluid nozzle operating pressure value, for example from a pressure range of 100,000 - 800,000 Pa, and to actuate the valve device (160) such that the second coolant component (300-2) is directed to the second inlet port (112-2) of the mixing chamber (112). Device (112) according to claim 3, characterized in that the control device (170) is configured to control the valve control device (160) in a first variant of the two-fluid nozzle operating state in such a way that the supply of the second coolant component (300-2) to the inlet port (130-1) of the coolant channel (130) is completely prevented, or to control the valve device (160) in a second variant of the two-fluid nozzle operating state in such a way that the supply of the second coolant component (300-2) to the inlet port (130-1) of the coolant channel (130) only takes place with a single-fluid nozzle protective flow. Device (100) according to one of the preceding claims, characterized in that the valve assembly (160) is formed from a 3-way switching valve or from two two-way switching valves. Device (100) according to one of the preceding claims, characterized by a two-fluid nozzle tube (180) for connecting the outlet port (112-3) of the mixing chamber (112) to the two-fluid nozzle (120); and a single-fluid nozzle tube (190) for connecting the outlet port (130-2) of the coolant channel (130) to the single-fluid nozzle (140). Device (100) according to claim 6, characterized by a sheathing tube (195) in which the two-component and the single-component nozzle tube (180, 190) are guided together. Device (100) according to one of the preceding claims, characterized in that the valve assembly (160) is structurally integrated into the nozzle body (110) and the nozzle body (110) has an inlet port (162) for the second coolant component (300-2). Device (100) according to claim 8, characterized in that the nozzle body (110) has a control input (164) for the valve device (160). Device (100) according to claim 9, characterized in that the control input (164) of the valve device (160) is designed as a pressure switching input or as an electromechanical switching device and is connected via a branch line (166) to the supply line or the input port (112-1) for the first cooling component (300-1) in the mixing chamber (112). Device (100) according to claim 9, characterized in that the control input (164) of the valve device (160) is led outside the nozzle body (110). Device (100) according to claim 10, characterized in that the control device (170) is configured to control the pressure setting device (150) in the single-fluid nozzle operating state such that the two-fluid nozzle (120) is supplied with the first coolant component (300-1) only at a two-fluid nozzle protective pressure value, for example less than 50,000 Pa, and the valve device (160) is configured to direct the second coolant component (300-2) only to the inlet port (130-1) of the coolant channel (130) and thus to the single-fluid nozzle (140) when responding to the two-fluid nozzle protective pressure supplied via the branch line (166) at its control input (164). Device (100) according to claim 10, characterized in that the control device (170) is configured to control the pressure setting device (150) in the two-fluid nozzle operating state such that the first coolant component (300-1) is supplied with a two-fluid nozzle operating pressure value, for example from a pressure range of 100,000 - 800,000 Pa, and the valve device (160) is configured to direct the second coolant component (300-2) to the second inlet port (112-2) of the mixing chamber (112) at its control input (164) in response to the two-fluid nozzle operating pressure supplied via the branch line (166).

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