JPH04129504U - Cooling equipment for high temperature steel materials - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an easy-to-maintain cooling device for uniformly and highly accurately cooling high-temperature steel materials such as hot steel plates. [Structure] A cooling device for high-temperature steel is connected to a lower header 21 that is connected to a water supply pipe 5 and has a slit-shaped header outlet 20 at the top, a nozzle inlet hole 22 at a predetermined interval in the longitudinal direction, and a nozzle inlet hole 22 that is perpendicular to this. A communication hole 23 is provided, and the communication hole 23
It consists of an upper header 25 with a curved pipe nozzle 24 connected to the outlet thereof, and an orifice plate 27 having 26 groups of fine holes provided in the longitudinal direction at the same intervals as the nozzle inlet holes 22, and the lower header 21 and the upper The header 25 is removably fixed with the orifice plate 27 sandwiched between the header outlet 20 of the lower header and the nozzle inlet hole 22 of the upper header.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea is a device that cools high-temperature steel materials such as hot steel plates uniformly and with high precision. Regarding.

0002

[Prior art and its issues]

As a device for cooling high-temperature steel materials with a refrigerant such as water, the devices shown in Figure 5 (longitudinal cross-sectional view) and A pipe-shaped nozzle 1 is used as a refrigerant discharge nozzle as shown in Fig. 6 (front view). A "pipe lamina cooling device" is known that generates laminar flow. When cooling the top surface of a steel plate on a hot rolling hot run table, the plate jumps. To prevent damage caused by curling up, the cooling nozzle of the cooling device should be placed 1.2~ It is necessary to place it at a position approximately 1.8 m above, but even in such a case, the above Pipe lamina cooling equipment has a very high cooling capacity, so this pipe Lamina cooling devices continue to be the most widely used cooling devices today.

0003 However, in recent years, improvements have been made in terms of uniformity and precision in cooling high-temperature materials. Due to the increasing demand for control, the pipe lamina cooling system Various problems have also been pointed out. For example, when hot working a steel plate online, the following In the next type of cooling system, service continues even after the control valve stops supplying refrigerant to header 2. Refrigerant often continues to be discharged from several pipe-shaped nozzles 1 due to the Ifon effect. Since it is not possible to instantly stop the refrigerant discharge from the nozzle group, It is not possible to precisely control the steel plate temperature by ON/OFF control of refrigerant supply. won.

0004 In addition, in order to achieve uniform cooling in the plate width direction, a uniform flow distribution in the longitudinal direction of the header is required. Therefore, for example, as shown in FIG. 5, a large number of pores 3 are Measures such as supplying the refrigerant into the header 2 through the rectifier pipe 4 that is evenly perforated in the direction However, these methods were not fully satisfactory. However, it was not possible to achieve uniform flow distribution. In addition, a rectifier tube with pores is attached. Then, especially when the cooling device is used online, the scale contained in the refrigerant is The pores are likely to become clogged due to dirt, etc., so remove the header. This also leads to the problem of difficult maintenance due to the increased frequency of internal cleaning. Ta.

[0005] Furthermore, two or more refrigerant supply pipes 5 (see FIG. 6) are connected to both ends of one header 2 or The refrigerant inflow pressure in each supply pipe is connected at equal intervals in the longitudinal direction. Equalizing the forces equalizes the pressure distribution inside the header, thereby reducing the header length. Attempts have also been made to achieve uniform flow distribution of refrigerant in the hand direction; Not only was it not possible to ensure sufficient uniformity of flow rate distribution depending on the stage, but there was also a problem with multiple refrigerant supplies. The piping becomes complicated due to the need for supply pipes, and the space and cost required to install the equipment are reduced. A new problem has arisen in that it is subject to major constraints.

[0006] Therefore, in order to solve these problems, each input of a group of pipe-shaped nozzles was Individual orifices are installed at the mouth or in the middle of the pipe to allow flow into each pipe-shaped nozzle. By sufficiently throttling the refrigerant flow to each nozzle, we can accurately adjust the refrigerant flow rate to each nozzle. There are proposals to adjust the flow rate to create a uniform flow distribution in the longitudinal direction of the header. It's starting to turn sour.

[0007] For example, the one shown in Fig. 7 has an orifice in the rising part of the pipe-shaped nozzle 1. 6 is removably inserted to adjust the flow rate of refrigerant flowing into the nozzle. By providing ventilation holes 7 inside the curved part of the top of the pipe, uniform cooling performance and water draining response are achieved. This is a proposal (Utility Model Publication No. 62-5765) to increase the

[0008] In addition, the one shown in FIG. 8 has a mountain-shaped press molded body on the top of the cylindrical header 2. 8 is removably attached to form an inflow chamber for the refrigerant from the header 2, and a An orifice piece 10 is attached to the upper end opening of the nozzle 9 that hangs down from the medium inflow chamber for uniform cooling. This is a proposal (Utility Model Publication No. 63-44168) aimed at ensuring performance and temperature controllability.

[0009] Furthermore, in the case shown in FIG. 9, the refrigerant flows into the upper part of the header 2 from the header 2. The second header 11 is connected, and a nozzle hole 12 is provided on the side of the second header 11. By guiding the refrigerant to the nozzle groove formed between two possible nozzle plates 13 and 14. Proposal to ensure uniform cooling ability and temperature controllability (Utility Model Application No. 111209/1983) It is.

0010 A separate orifice is provided at the entrance of the pipe nozzle as described above or in the middle of the pipe. or by providing small holes in the upper side wall of the nozzle plate to guide the refrigerant. As a result, uniform cooling ability and temperature control ability were further improved; In fact, the following problems were recognized.

[0011] That is, as in the above-mentioned Utility Model Publication No. 62-5765, an orifice is individually set for each nozzle. If you remove the nozzle from each nozzle when cleaning limescale, etc. that has adhered to the orifice, need to be done and requires a lot of effort. Furthermore, the pipe-shaped nozzle is used to When cooling plates, etc., reduce uneven cooling in the width direction of the plate due to overcooling at the point where the refrigerant falls. In order to eliminate this problem, it is necessary to arrange the nozzles as closely as possible, but The device proposed in No. 62-5765 has a nozzle for attaching and detaching the orifice during cleaning. Each nozzle has a flange for fixing the orifice, which prevents nozzles from being arranged closely. It is difficult to improve uniform cooling performance.

0012 Also, as in the above-mentioned Utility Model Publication No. 63-44168, an orifice piece is installed at the upper end of the nozzle. When the flow condenses at the orifice, it falls directly into the nozzle pipe. Air pockets form inside the nozzle pipe and the flow is not sufficiently rectified, thus preventing the refrigerant flow from being cooled. The effect of penetrating the liquid pool on the surface of the material to be cooled and disturbing it when it falls on the surface of the material is reduced, Cooling capacity decreases.

[0013] In the device proposed in Utility Model Application No. 63-111209, the nozzle flow path In order to make it cylindrical, a large number of semi-cylindrical grooves are machined on both nozzle plate surfaces. Therefore, it costs a lot of money to manufacture.

[0014] For this reason, the purpose of this invention is to solve the problems pointed out by conventional cooling devices. By eliminating the above problem, a uniform flow distribution in the longitudinal direction of the header can be obtained, and the material to be cooled can be cooled. Uniform cooling can be achieved in the width direction, as well as excellent ON/OFF controllability. The object of the present invention is to provide a cooling device for high-temperature steel that is easy to maintain.

[0015]

[Means to solve the problem]

The present invention has been made to achieve the above objectives, ``As illustrated in Figure 1 (longitudinal cross-sectional view) and Figure 2 (partially cutaway front view), high-temperature steel The cooling device is connected to the water supply pipe 5 and has a slit-shaped header outlet 20 at the top. The lower header 21 has a nozzle hole 22 at a predetermined interval in the longitudinal direction and a series perpendicular to the nozzle hole 22. A connecting hole 23 is provided, and a bent pipe nozzle 24 is connected to the outlet of the connecting hole 23 to the upper part. a header 25, and a group of 26 small holes provided in the longitudinal direction at the same intervals as the nozzle holes 22. and an orifice plate 27, and the lower header 21 and the upper header 25 are connected to the lower header. The orifice plate 27 is sandwiched between the header outlet 20 of the header and the nozzle inlet hole 22 of the upper header. Excellent ON/OFF control by holding and removably fixed structure In addition to being easy to maintain and maintain, it also has remarkable uniform cooling properties in the width direction of the material to be cooled. "We've made a lot of improvements." It has major characteristics.

[0016]

[Effect]

The details of the cooling device for high-temperature steel materials and its actions (functions) according to the present invention are explained below. An example will be explained based on drawings. 1 and 2 are explanatory diagrams schematically showing one example of a cooling device according to the present invention (FIG. 1 is a vertical view). 2 is a partially cutaway front view), and shows the cylindrical lower head connected to the water supply pipe 5. The header 21 has a structure with a slit-shaped header outlet 20 extending in the longitudinal direction at the top. It is said that

[0017] In addition, the upper header 25 is made of a single prismatic column, and extends in its longitudinal direction. A plurality of nozzle holes 22 are provided from the bottom surface to match the arrangement interval of each curved pipe nozzle 24. A plurality of corresponding communication holes 23 are provided from the sides, and the tips of the holes 23 connect the two. It has a structure in which the two are perpendicular to each other. Of course, the upper header 25 does not necessarily have an integral structure. Although it is not necessary and takes more time to manufacture, there is no problem with a split structure. Each outlet of each communication hole 23 turned on the side of the upper header 25 is bent at 90 degrees. The curved pipe nozzle 24 is connected by welding and supported by nozzle support plates 28, 28. held.

[0018] The lower header 21 and the upper header 25 are made up of an oval material having a large number of pores 26 between them. They are connected by bolts with the orifice plate 27 sandwiched therebetween. In addition, the code 29 in the figure is the It shows the Note that the cooling device with the structure described above can be easily manufactured by ordinary hole drilling. Since it does not require particularly precise machining, conventional orifice-mounted pipes are The production cost can be significantly reduced compared to a nozzle.

[0019] Now, in the cooling device according to the present invention, each nozzle inlet of the 24 groups of curved tube nozzles is Since the orifice plate 27 having a large number of 26 groups of pores is inserted, each The flow of refrigerant flowing into the nozzle inlet is controlled by the pores 26 provided in the orifice plate 27. As the nozzle is sufficiently narrowed down, the flow rate distribution of each nozzle becomes very uniform. That is, when the orifice plate 27 is inserted into the inlet of each nozzle, the refrigerant flows through the orifice. While passing through the pores 26 of the refrigerant supply pipe 27, a “head” is generated at the installation position of the refrigerant supply pipe 5. Since the pressure loss is sufficiently large compared to "uneven pressure distribution inside the pipe," The influence of the above-mentioned non-uniformity caused by the application position is canceled out as much as possible, and each nozzle is This means that the flow rate distribution becomes significantly more uniform.

[0020] In this case, the inner diameter of the pores 26 provided in the orifice plate 27 is smaller than the nozzle inner diameter. The more uniform the pores are, the better the uniformity effect will be, but if the inner diameter of the pores is made too small, clogging will occur. However, considering the maintenance aspect, the inner diameter of the pores may be smaller than the nozzle. It can be said that it is practical to set the diameter to about 1/2 or less of the inner diameter of the tube.

[0021] In addition, if you want to make the flow distribution in each nozzle even more uniform, use the orifice. The diameter distribution of the 26 groups of pores provided in the base plate 27 in the longitudinal direction of the header is uniform in the longitudinal direction. The distribution calculated to obtain a flow rate distribution, that is, the pressure in the pores and nozzle pipes. It is preferable to use an optimal pore diameter distribution calculated taking loss into consideration.

In other words, if we take the case where water is supplied by connecting a water supply pipe to one end of the header, the total number of nozzles (pores) is N, and the cross-sectional area a _n of the nth pore from the water supply pipe is the header pipe. The value divided by the cross-sectional area A ₀ is a _n ^* , the water supply amount is Q _in , and the cooling water density is ρ, and the pressure P _n on the pore entry side and the water supply pressure P _in are ρ (Q _in /A ₀ ) ² . Let the divided values be P _n ^* and P _in ^* respectively, and the flow rate of each pore part be q, and let Q _n ^* = (N-n) q/Q _in = (N-n)/N, then in the header ^Using _Bernoulli ^'s _{theorem for} ^{the cooling water} _{flow at _ 1} ^*3 - _Qn ^*3 )/(Qn _-1 ^* + _Qn ^* ) [where n=1 to N]...(3) Find the head internal pressure distribution _Pn . That is, using equation (3), calculate in the order of P ₀ → P ₁ → P ₂ → ... → P _n . Similarly, using Bernoulli's theorem for this result and the flow inside the orifice,

[Math 1] Accordingly, the optimal pore cross-sectional distribution a _n ^* can be calculated. However, Cf is the pressure loss coefficient determined by the channel shape of the pore and nozzle. For example, in the case of the channel structure shown in Figs. 1 and 2, Cf = C ₁ + C where A _p is the cross-sectional area of the nozzle. ₂ (A _p / a _n ) ... Calculate according to (5). Here, C ₁ and C ₂ differ depending on the shape, but according to experiments conducted by the present inventor, it was found that C ₁ =0.5 to 2 and C ₂ =1 to 3. Furthermore, as can be seen from equations (1) to (3) above, Q _n ^* and P _n ^* are related only to the number N of pores. Therefore, the pore area distribution a _n ^* is uniquely determined when Cf and N are given, and does not depend on the water supply flow rate Q _in .

Therefore, if you design by finding a _n ^* for the average usage flow rate, even when cooling is performed while changing the usage flow rate online, the orifice plate 27 will always be uniform without having to be replaced. It is possible to obtain a suitable flow rate distribution.

[0024] In addition, in the cooling device according to the present invention, the depth of the nozzle insertion hole 22, that is, the “nozzle rise The height h from the orifice plate 27 to the innermost wall of the nozzle hole, which corresponds to the height of the (See Figure 1) can be made sufficiently small, so when the refrigerant supply to the header is stopped, the bent pipe nozzle Refrigerant discharge from 24 is stopped instantaneously, resulting in excellent ON/OFF controllability. I can do that.

[0025] In other words, in the case of conventional pipe lamina cooling systems, the refrigerant supply stops due to its structure. If this happens, refrigerant will remain on the rising edge of each nozzle connected to the header. However, if some nozzles are not tightly closed and refrigerant continues to drip, the refrigerant supply pipe Even if the refrigerant supply from the The discharge (droplet) continues until the refrigerant is exhausted and the liquid level drops to the header connection. ) does not stop, and the response when turned off is extremely poor. On the other hand, the nozzle In the cooling device according to the present invention, which can minimize the depth of the hole 22, the Since the refrigerant capacity is very small, refrigerant discharge can be stopped instantaneously when turned off. This is the reason. Note that the smaller the depth of the nozzle hole 22, the better the response, but due to the structure, It can be said that it is preferable that the diameter is about 3 times or less the inner diameter of the nozzle.

[0026] Furthermore, the cooling device according to the present invention uses an orifice plate 27 having 26 groups of pores. This restricts the flow of refrigerant at the nozzle inlet, causing refrigerant to flow from some nozzles. The phenomenon of continuous discharge of refrigerant becomes even more difficult to occur, and as soon as the refrigerant supply is stopped, all Refrigerant discharge from the nozzle is stopped, and ON/OFF response is further improved.

[0027] Moreover, the flow is restricted by the pores 26 of the orifice plate 27 interposed in the refrigerant flow path. once rises up the rising part (nozzle entry hole) and collides with the upper wall of nozzle entry hole 22. The momentum is weakened. Then, the inside of the nozzle hole is filled with refrigerant, and then the refrigerant is Since it passes through the communication hole 23 and is supplied to the nozzle 24, it is effectively rectified. Therefore, Compared to the type that does not have a rising part and the refrigerant flow immediately falls inside the nozzle. A significantly rectified refrigerant discharge flow can be obtained.

[0028] In addition, the cooling device according to the present invention also has the following major features: Can be done. That is, the upper header 25 in which the entire group of bent tube nozzles 24 is fixed at predetermined intervals, It is removably fixed to the lower header 21 with the orifice plate 27 and packing 29 in between. The point is that it has a suitable structure. When a cooling device for high-temperature steel is applied to an actual production line, the scale contained in the refrigerant is There is a risk of clogging, especially in the pores of the orifice plate 27, due to the adhesion of metal particles, etc. However, as mentioned above, it has a group of pores. The orifice plate 27 is removably held between the upper and lower headers. This makes it extremely easy to remove the bent pipe nozzle 24 and orifice plate 27 during cleaning. Become so. In addition, for cleaning in the event of sudden clogging, 24 groups of curved pipe nozzles can be installed on the upper header. Maintenance is very easy as it can be easily done by removing every 25 minutes. Simplify.

[0029] Note that FIG. 3 shows the openings in the orifice plate 27 in the cooling device according to the present invention shown in FIG. A similar device in which the inner diameter of the 26 groups of large pores is set to 1/2 of the inner diameter of the curved pipe nozzle 24 For those that do not use orifice plate 27 (corresponding to conventional equipment), Flow rate in the longitudinal direction of the header when cooling water is supplied from one side of the header It shows the measurement results for "Cloth".

[0030] From the results shown in Figure 3 above, if the orifice plate 27 is not used, the water volume distribution However, in the device of this invention using the orifice plate 27, the non-uniformity of the The above-mentioned non-uniformity is kept to 3% or less, and the uniformity in the width direction is significantly improved, making it practical. It can be seen that excellent characteristics are obtained. In addition, the diameter distribution of the 26 groups of pores drilled in the orifice plate 27 is composed of pores and curved pipe nozzles. If the calculated value is taken into account the pressure loss in the pipeline, the non-uniformity will be approximately 1 %, and the uniformity of the water amount distribution is further improved than in the case of uniform distribution. was also confirmed.

[0031] Figure 4 also shows the water supply to the header using the same equipment in which the results in Figure 3 were obtained. OFF characteristics when stopped, that is, the time required until the discharge of cooling water from the nozzle stops This shows the results of the survey. As can be seen from Figure 4, the OFF response of the device according to the present invention is also significantly greater than that of the conventional device. It is clear that it is possible to control the steel plate temperature with high precision as the Ru.

[0032]

[Summary of effects]

As explained above, according to this invention, the material to be cooled, such as a high-temperature steel plate, can be uniformized in the width direction. It can be cooled all at once, and has excellent ON/OFF controllability, making it possible to precisely control the cooled material. In addition to being able to provide temperature control, we can also provide cooling equipment that is easy to maintain. Moreover, useful effects are brought about.

[Brief explanation of drawings]

FIG. 1 is an explanatory longitudinal cross-sectional view of a cooling device according to the present invention.

FIG. 2 is a partially cutaway front view of the cooling device according to the present invention.

FIG. 3 is a graph comparing the flow rate distribution in the longitudinal direction of the header between the cooling device according to the present invention and that of a conventional cooling device.

[Figure 4] Turning off the cooling device according to the present invention and the conventional one
This is a graph comparing the responsiveness over time.

FIG. 5 is an explanatory longitudinal cross-sectional view of a conventional cooling device.

FIG. 6 is a schematic front view of a conventional cooling device.

FIG. 7 is an explanatory diagram of a conventionally proposed cooling device.

FIG. 8 is an explanatory diagram of another conventional proposed cooling device.

FIG. 9 is an explanatory diagram of yet another proposed conventional cooling device.

[Explanation of symbols]

1 Pipe nozzle 2 header 3 Pore 4 Rectifier tube 5 Refrigerant supply pipe 6 Orifice 7 Ventilation hole 8 Mountain-shaped press molded body 9 Nozzle 10 orifice piece 11 Second header 12 Nozzle hole 13 Nozzle plate 14 Nozzle plate 20 Lower header slit exit 21 Lower header 22 Nozzle hole 23 Communication hole 24 Bent tube nozzle 25 Top header 26 Pore 27 Orifice plate 28 Nozzle support plate 29 Packing

Claims (2)

[Scope of utility model registration request] Claim 1: A lower header connected to a water supply pipe and provided with a slit-shaped header outlet at the top, a nozzle inlet hole and a communication hole orthogonal to the nozzle inlet hole provided at a predetermined interval in the longitudinal direction; It is composed of an upper header having a curved pipe nozzle connected to the outlet of the hole, and an orifice plate having a group of fine holes provided in the longitudinal direction at the same intervals as the nozzle entrance holes, and the lower header and the upper header are A cooling device for high-temperature steel, characterized in that the orifice plate is sandwiched and removably fixed between a header outlet of a lower header and a nozzle inlet hole of an upper header. 2. The diameter distribution of the pore group provided in the orifice plate in the longitudinal direction of the header is a distribution calculated to obtain a uniform flow rate distribution in the longitudinal direction. Cooling system.