阅读说明：本技术 层流冷却装置的冷却组 (Cooling group of laminar flow cooling device ) 是由 J·阿尔肯 H·贝格 J·基斯林-罗马纽斯 于 2019-02-07 设计创作，主要内容包括：本发明涉及层流冷却装置(1)的冷却组,在该冷却组中,至少一个冷却组布置在待冷却的带材的上方以及下方,以便为带材加载冷却液,该冷却组包括：中央输入部(2),通过该中央输入部输送冷却液；由中央输入部(2)供给冷却液的分配管(3)；和多个加载单元(4),其由分配管(3)供给冷却液,其中,在每个加载单元(4)处布置有多个冷却喷嘴(5),通过冷却喷嘴将冷却液施加到带材上。为了使接通或断开的加载单元的数量的影响最小化并且在此具有尽可能低的投资花费,本发明规定,在中央输入部(2)中或在中央输入部(2)之前布置有体积流调节阀,通过该体积流调节阀每单位时间导引限定体积的冷却液通过中央输入部(2)。(The invention relates to a cooling group of a laminar flow cooling device (1), in which at least one cooling group is arranged above and below a strip to be cooled in order to load the strip with a cooling liquid, comprising: a central input part (2) through which the coolant is fed; a distribution pipe (3) for supplying the cooling liquid from the central input part (2); and a plurality of loading units (4) which are supplied with cooling liquid by the distribution pipe (3), wherein a plurality of cooling nozzles (5) are arranged at each loading unit (4), through which cooling liquid is applied to the strip. In order to minimize the influence of the number of load cells switched on and off and to have the lowest possible investment cost, the invention provides that a volume flow control valve is arranged in the central inlet (2) or upstream of the central inlet (2), by means of which volume flow control valve a defined volume of cooling liquid is guided per unit time through the central inlet (2).)

1. Cooling group of a laminar cooling device (1), in which at least one cooling group is arranged above a strip to be cooled and at least one cooling group is arranged below the strip to be cooled in order to load the strip with a cooling liquid, comprising: a central input part (2) through which the coolant is fed; a distribution pipe (3) to which the coolant is supplied from the central input portion (2); and a plurality of loading units (4) which are supplied with cooling liquid from the distribution pipe (3), wherein a plurality of cooling nozzles (5) are arranged at each loading unit (4), through which cooling liquid is applied to the strip, characterized in that a volume flow regulating valve (6) is arranged in the central inlet (2) or before the central inlet (2), through which a defined volume of cooling liquid is guided through the central inlet (2) per unit time.

2. The cooling group of laminar flow cooling arrangements according to claim 1, characterised in that it is configured to guide at 30m per strip side by means arranged above or below the strip to be cooled³/m²h and 200m³/m²Volume flow between h.

3. The cooling group of laminar cooling devices according to claim 1 or 2, characterized in that the ratio of the cross section of the distribution pipe (3) and the cross section of the loading unit (4) is at least 1.0.

4. The cooling group of laminar cooling devices according to claim 3, characterized in that the ratio of the cross section of the distribution pipe (3) and the cross section of the loading unit (4) is at least 1.5.

5. The cooling group of laminar cooling devices according to any of claims 1 to 4, characterized in that, in the case of a laminar cooling device (1) arranged above the strip to be cooled, it is configured such that the ratio of the flow rate in the distribution pipe (3) to the flow rate in the loading unit (4) is in the range between 0.6 and 3.0.

6. The cooling group of laminar cooling devices according to any of claims 1 to 5, characterized in that, in the case of a laminar cooling device (1) arranged below the strip to be cooled, it is configured such that the ratio of the flow rate in the distribution pipe (3) to the flow rate in the loading unit (4) is in the range between 0.2 and 1.0.

7. The cooling group of laminar flow cooling apparatus according to any of claims 1 to 6, characterized in that the Reynolds number in the central inlet (2), the distribution pipe (3) and/or the loading unit (4) is between 2000 and 3000.

8. The cooling group of a laminar flow cooling arrangement according to any of the claims 1 to 7, characterized in that the cooling group is configured to maintain a pressure above 0.05bar in a loading unit (4) arranged above the strip.

9. The cooling group of a laminar flow cooling apparatus according to any of claims 1 to 8, characterized in that it is configured to maintain the pressure in a loading unit (4) arranged below the strip above 0.025 bar.

10. The cooling group of laminar flow cooling arrangements according to any of claims 1 to 9, characterized in that the setting of the volume flow regulating valve (6) is determined on the basis of the following relation

Wherein the content of the first and second substances,

is the total theoretical volume flow, and

is the theoretical sub-volume flow in each loading cell (4.1, 4.2, … …).

11. The cooling group of laminar cooling devices according to claim 10, characterized in that said theoretical volumetric flowIs regulated by a regulating section (8), by means of which the setting of the volume flow regulating valve (6) is preferably changed taking into account a correction value (Korr.) for setting the flow rate.

12. The cooling group of laminar flow cooling apparatus according to any of claims 1 to 11, characterized in that at least six, preferably at least eight loading units (4) are arranged one after the other in the conveying direction (F) of the strip.

Technical Field

The invention relates to a cooling group of a laminar cooling device, in which at least one cooling group is arranged above a strip to be cooled and at least one cooling group is arranged below the strip to be cooled in order to load the strip with a cooling liquid, comprising: a central input portion through which a coolant is conveyed; a distribution pipe supplied with the cooling liquid from the central input part; and a plurality of loading units supplied with cooling liquid by a distribution pipe, wherein a plurality of cooling nozzles through which the cooling liquid is applied to the strip are arranged at each loading unit.

Background

Typically, laminar cooling devices of this type (laminar cooling sections) for cooling rolled metal strips are divided into individual cooling groups. Each cooling group comprises a central input and a distribution pipe which opens into at least four or more loading units (chilled beams) arranged above or below the metal strip to be cooled. The group arranged directly after the rolling process preferably has a higher flow than the group located at the cooling end or just before the coil.

Cooling devices of this type are disclosed, for example, in CN103861879, CN102397888, CN102513385 and CN 203419952U.

The defined cooling curve is set as a prerequisite for a defined cooling strategy according to which the individual loading units of the cooling group release the water quantity such that the preset cooling curve is achieved and the desired theoretical temperature (coiling temperature) is maintained during coiling when process parameters change, for example the rolling speed or the final rolling temperature changes.

The precondition for this is that a precisely set, in the best case identical amount of water is always discharged from the individual loading units, regardless of what switching state occurs in the cooling group.

For this purpose, according to a first known solution, the supply to the cooling group is realized by a high-level container filled with cooling water, via which a fixed pre-pressure is supplied to the delivery of the cooling group. Immediately before each loading unit is a switching element, which is either completely open or completely closed, depending on whether cooling water should be applied to the metal strip from the respective unit.

The disadvantage in this case is that the initially constant pre-pressure leads to a pressure loss as a function of the flow rate in the guide system, which reduces the amount of water flowing in the loading unit as a function of the switching state. The disadvantage is therefore that the individual throughflow through the load units depends on the switching state of the entire group. The cooling strategy for strip cooling can therefore only be operated imprecisely.

According to a second known solution, a flow regulator is arranged upstream of each loading unit. The desired amount is thus set at this time independently of the preload.

However, a disadvantage in this solution is that the effort to be expended for this is high and therefore a high investment is required; furthermore, the expenditure on the control technology is significantly higher here than in the variants described above.

Disclosure of Invention

It is therefore an object of the present invention to provide a laminar flow cooling device of the type mentioned at the outset in such a way that the influence of the number of switched-on or switched-off loading units on the flow rate and flow of water is kept to a minimum. However, it is ensured here that the investment costs are kept as low as possible.

The solution of the object of the invention is characterized in that a volume flow regulating valve is arranged in or before the central inlet, by means of which a defined volume of cooling liquid is guided through the central inlet per unit time.

The solution according to the invention ensures in a simple, yet effective manner that the loading unit is supplied with the exact amount of fluid required for setting the cooling rate. In consideration of the following design features, the pressure loss at the short guide section is negligible, so that the loading units of the cooling group can be supplied uniformly.

The laminar cooling device is preferably designed to guide the strip to be cooled at 30m on each side of the strip by means arranged below or above the strip³/m²h and 200m³/m²Volume flow between h.

The ratio of the cross section of the distribution pipe and the cross section of the loading unit is preferably at least 1.0; particularly preferably, a value of at least 1.5 is set for this ratio.

In the case of a laminar cooling device arranged above the strip to be cooled, the laminar cooling device is preferably designed such that the ratio of the flow rate in the distribution pipe to the flow rate in the loading unit is in the range between 0.6 and 3.0.

In the case of a laminar cooling arrangement arranged below the strip to be cooled, the ratio of the flow rate in the distribution pipe to the flow rate in the loading unit is preferably in the range between 0.2 and 1.0.

The reynolds number in the central inlet, the distribution pipe and/or the loading unit is preferably between 2000 and 3000. Here, the reynolds number is the product of the density of the cooling medium and the flow rate and the characteristic length (reference length) of the body flowing through divided by the dynamic viscosity of the cooling medium.

The laminar cooling device is preferably designed such that the pressure in the loading unit arranged above the strip is maintained above 0.05 bar.

The laminar cooling device is preferably designed such that the pressure in the loading unit arranged below the strip is kept above 0.025 bar.

The setting of the volume flow control valve is preferably determined by the following relationship:

wherein the content of the first and second substances,

is the total theoretical volume flow, and

is the theoretical sub-volume flow in each loading cell (4.1, 4.2, … …).

In this case, provision is preferably made for the setpoint volume flow to be adjusted by means of an adjusting section, by means of which the volume flow regulating valve is preferably changed in its setting taking into account a correction value for the flow rate setting.

The amount of cooling water per loading unit is calculated according to the provisions of a per se known cooling strategy. The total coolant requirement is derived from the sum of the cooling water quantities of the individual load cells (1 to n) according to the above formula. The amount of cooling water for each loading unit may be the same or different in each unit.

Preferably, at least six, particularly preferably at least eight, loading units are arranged in succession in the cooling group in the conveying direction of the strip.

The proposed solution is therefore based on placing a volume flow regulating valve before each cooling group, which volume flow regulating valve regulates the desired flow in the group independently of the pre-pressure. Furthermore, the ratio of the diameters of the input and the cooling beam (the ratio of the cross sections) is selected in a special way. This ensures that switching on and off the load units of a group (in either case) does not affect the local throughput of the individual load units.

Therefore, preferably a cooling section is provided which is adjusted in groups, in which cooling section each side of the belt is arranged at 30m³/m²h and 200m³/m²h, a specific loading between h. Here, the ratio of the cross-sections between the distribution pipe/chilled beam is at least 1.0, preferably at least 1.5. The speed ratio between the distribution pipes/loading units of the upper cooling group is preferably between 0.6 and 3.0; in the lower cooling groupThe speed ratio between the distribution pipe/loading unit of (a) is preferably between 0.2 and 1.0.

The upper loading unit is operated at a pressure of at least 0.050bar and the lower loading unit is operated at a pressure of at least 0.025 bar.

The proposed solution provides a cooling device for cooling slabs or strips, with which an improved cooling effect can be achieved.

The flow rate of the coolant is directly measured and regulated, so that a predefined value of the volume flow can be precisely maintained. At least one regulating section is provided for this purpose in order to regulate the flow range. For this purpose, at least one flow meter and at least one control valve are provided, which are arranged at corresponding points of the inlet.

Whereby the amount of coolant and the area loaded can be varied.

The cooling device and its cooling power are preferably integrated into the process model.

Improvements in the accuracy and speed of adjustment of the cooling load (e.g., with regard to "belt acceleration", structure setting and non-uniformity of the strip) can be achieved by the proposed device or corresponding method.

Drawings

Embodiments of the invention are shown in the drawings. The single figure shows a schematic illustration of a cooling group of a laminar cooling device, which cools the top side of a strip, not shown.

Detailed Description

In this embodiment, the cooling group of the laminar cooling device 1 comprises five loading units 4 in the form of chilled beams, which are arranged one after the other in the transport direction F of the strip (not shown). Preferably, 6 to 8 loading units 4 are combined into one cooling group. For reasons of simplicity of illustration, it has been omitted in fig. 1. The chilled beam 4 is provided with a plurality of cooling nozzles 5 which apply a cooling agent to the strip (not shown) from above.

The coolant is supplied through a central inlet 2 from which coolant is supplied to the distribution pipes 3. The coolant reaches the chilled beam 4 from the distributor pipe 3.

It is important that a volume flow regulating valve 6 is arranged in the central inlet 2 or upstream of the central inlet 2, by means of which a defined cooling liquid volume per unit time is conducted through the central inlet 2.

The flow through the central inlet is measured directly by means of the flow measuring section 7 and is adjusted according to the measurement result. For each flow range, a respective (at least) control section 8 is provided, in which the measured actual value is compared with the setpoint value and the setting of the control valve 6 is changed, if necessary, by a correction value (Korr.) for the flow setting. Depending on the flow, at least one flow meter and/or a regulating valve is provided at the separate line.

The individual loading units 4.n can be set with regard to their flow rate by means of the valve 9, but can also be switched on or off. This makes it possible to vary not only the cooling rate but also the loading area. Alternatively, the valve 9 may also be configured as a pure switching valve (on/off) to provide only a switch surface. By incorporating into the regulating part, a change in the setpoint value presetting of the coolant demand can compensate for the cooling rate and/or the cooling area of the respective loading unit without negative effects.

The amount of coolant and the loading area can be varied. The regulating mechanism regulates the throttle orifice (blend) in order to cope with the back pressure (at least 40% of the total pressure loss) and thus to achieve a stepless, volume-controlled water supply, in particular between 40% and 100% of the total water quantity.

The desired switching state can be checked by flow measurement or monitored in automation.

Additionally, a functional unit for checking the cooling mechanism or the loading unit may be provided. For this purpose, active reactions in the process module can be carried out during operation. A functional failure may be determined during a maintenance cycle.

The entire water resource management can be integrated here and the pump control can be carried out by means of the calculated and set water quantity. So that only the mass required for the cooling task is released by the pump.

List of reference numerals

Cooling group of 1 laminar cooling device

2 central input unit

3 distributing pipe

4 Loading unit (chilled beam)

4.1 Loading Unit (chilled beam)

4.2 Loading Unit (chilled beam)

4.3 Loading Unit (chilled beam)

4.4 Loading Unit (chilled beam)

N load cell (chilled beam)

5 Cooling nozzle

6 volume flow regulating valve

7 flow rate measuring unit

8 regulating section

9 valve

F direction of conveyance