JPS62124214A - Method for controlling liquid feed rate of nozzle for controlled cooling device - Google Patents

Abstract

PURPOSE:To execute control with good accuracy without using costly apparatus as in the titled method for a controlled cooling device in direct heat treatment of materials after rolling by controlling the liquid feed rate to nozzles by combination of opening and closing of various valves of plural pipes. CONSTITUTION:This cooling device has a water feed source 10, a water feed main pipe 12, a water feed branch pipe 20 and nozzles 22 for ejecting cooling water and controls the flow rate of the cooling water 52 to be supplied to a steel sheet 40A which is a material to be cooled. Respective parallel pipelines 44A-44D for constituting the respective independent flow passages and valves 42A-42D which are respectively provided to said pieplines, have the functions to independently open and close the above-mentioned flow passages and are different in flow passage area from each other are provided between the pipes 12, 20. An opening and closing control device 46 for combining said valves and selectively opening and closing the valves is provided. The water 52 is first supplied from the source 10 via the pipe 12 to the pipelines 44A-44D. The combinations of the valves 42A-42D are selected and the selected valves are opened and closed by the driving signal from the device 46 so that the total sum of the flow rates of the water passing the respective valves is the water feed rate to the nozzles 22.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for controlling the amount of liquid supplied to a nozzle of a control cooling device, and in particular, a control method for directly heat-treating rolled material, which is suitable for use when adjusting water seedlings in a cooling device for cooling high-temperature steel plates, etc. This invention relates to an improvement in a method for controlling a nozzle liquid supply port of a cooling device.

[Conventional technology]

It is a well-known fact that material properties such as hardness and tensile strength can be improved by jetting high-pressure water onto the upper and lower surfaces of a high-temperature steel plate to cool it and heat-treating the steel plate. or,
In recent years, there has been remarkable progress in controlled cooling technology that allows a steel plate immediately after rolling to be cooled online at an arbitrary cooling rate depending on the plate thickness, alloy composition, etc., thereby enabling a wide range of material quality control. By the way, although there have been advances in the water cooling equipment used to cool steel sheets using the cooling technology described above, such as automation of valve opening and closing and higher accuracy of measuring instruments, there are still no essential methods for controlling the amount of cooling water. No significant progress has been made in this area, and many systems employ piping systems as shown in FIG. 5, for example. The water cooling system shown in FIG.
Flow to detect the amount of cooling water through! Send cooling water to ajt14. The cooling water that has passed through the flow meter 14 is transferred to a water supply branch pipe 20.
The water passes sequentially through a flow adjustment valve 16 for adjusting the flow port and a water control valve 18 for stopping the cooling water, and reaches the cooling water jetting nozzle 22 of the nozzle header, where it is jetted out to be cooled. Cool the material. In recent years, automation of measuring instruments has progressed, so the operation of the flow rate adjustment valve 16 is controlled by a control device 2 such as a host computer and/or an 8-system loop controller.
4, the signal from the flowmeter 14 is fed back to
I61] is controlled electrically and with high precision based on instructions from the device 24.

[Problems to be solved by the invention]

By the way, when cooling the material to be cooled, in order to adjust the cooling capacity over a wide range, it is necessary to use the nozzle 22.
The water G spewing out must be controlled over a wide range. Therefore, the opening adjustment range of the flow O adjustment valve 16 and the measurement range of the flow meter 14 must necessarily be widened. In this case, regarding the flowmeter 14, it is possible to measure a wide range of flow rates by using an electromagnetic ω meter or an ultrasonic flowmeter, but using such a meter increases the equipment cost. The problem is that it becomes extremely expensive. Regarding the flow level adjustment valve 16, theoretically, the flow rate can be controlled continuously and over a wide range by adjusting the valve opening.
7, but in reality it has the following problems. However, in the past, the current situation is that the flow ω of cooling water has been controlled without any effective and simple alternative technology to address such problems. (1) When the flow ft is small, that is, when the opening degree of the flow adjustment valve 14 is small, a large pressure difference occurs between the primary and secondary sides of the valve, which causes the valve body and the piping in the vicinity of the valve to cavitation may occur, causing damage to the valve body and piping. (2) When the pressure difference between the primary and secondary sides of the valve is large, even a small change in the valve opening will result in a very large change in flow rate. Therefore, it is easy to avoid the hunting phenomenon when using the feedback system. (3) If the flow rate is changed significantly, the amount of displacement of the valve body becomes large and it takes a long time. On the other hand, as a technique related to the present invention, for example, 53
-94247, a rolling mill roll coolant flow color control device is proposed. This is related to the heat crown control of rolling rolls that roll gold attenuated plates, and is equipped with a control valve that can control the coolant flow in stages by forming an arbitrary flow rate pattern in the roll axis direction by selecting the opening degree. This is the coolant flow control device. This device incorporates two valve pistons 30A and 30B with different flow characteristics as shown in FIG. 6, which are provided on the primary side of a coolant jet nozzle to control the heat crown of the rolling roll. One υJ1211
By selectively operating the valve 32 or adjusting the opening degree of the control valve 34 as shown in FIG. 7, coolant ejection o4i from the nozzle 22 is controlled in stages,
The cold section is controlled by adjusting the coolant flow rate jet pattern in the roll axis direction. However, since the valve pistons 30A and 30B of the control valve 32 as shown in FIG. 6 have a precise structure, they will not operate smoothly if foreign matter is present in the coolant, and this will cause serious problems in rolling operations. This will cause a lot of trouble. Similarly, the control valve 34 as shown in FIG. 7 is also extremely yi? Since the valve has a dense structure, if a foreign object is inserted between the poppet valve 36 and the valve seat 38, it will cause a fatal malfunction. Therefore, in order to operate the extremely precise and valuable control valves 32 and 34 as described above, it is necessary that the fluid used as the coolant be extremely clean, free of dirt and foreign matter, and that it itself be lubricated. It is necessary to have sex. Therefore, the above-mentioned coolant flow control device can only be used to control the RQ i, lJ of a coolant such as rolling oil or similar oils and fats, or special coolant oil, and cannot be used to heat-treat high-temperature steel plates. It cannot be applied to the flow rate control of cooling water that contains a large amount of scale, dust, etc., which is often used. In addition, when the number of nozzles is small, such as when cooling rolling rolls, the use of expensive valves such as the control valves 32 and 34 described above may be acceptable from a cost perspective. However, if a large number of expensive control valves such as those mentioned above are used for the large number of nozzles required for controlled cooling of high-temperature steel sheets, the problem is that the equipment cost will significantly increase and it will be impractical. It had

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional problems, and it is possible to speed up and increase the accuracy of flow rate control with a simple groove bottom without using expensive equipment, and prevent cavitation. An object of the present invention is to provide a nozzle supply liquid crystal control method for a controlled cooling flI device that can improve equipment life. [Means for Solving the Problems] The sixth invention provides a controlled cooling system for directly heat-treating the material after rolling.In this nozzle liquid supply amount control method, a plurality of mutually independent parallel pipes leading to the nozzle are connected to each other. By opening and closing the joint valve so that the total amount of liquid passing through the joint valve is the same as the liquid supplied to the nozzle, and adjusting the amount of cooling liquid, the above purpose can be achieved. It was completed.

[Effect]

Hereinafter, the effects of the present invention will be explained in detail. In the present invention, for example, when controlling the amount of cooling liquid supplied from the cooling water spouting nozzle 22 to the member to be cooled 40 as shown in the first factor, for example, cooling water sent from the water supply source 10, etc. For example, the cooling liquid in the main water supply room 12 and the water supply branch pipe 20
It is installed in the middle of the river, and each pipe is connected to a number of independent pipes. The pipe is provided with, for example, four valves 42Δ to 42D having different flow path areas, as shown in FIG. 1, in order to control the flow rate of the coolant flowing therethrough. , the respective valves 42A to 42D are opened and closed according to the amount of cooling liquid to be supplied to the liquid cooling material 40, and the liquid cooling material 40 is opened and closed.
The cold FA'a supplied to the A material 40 is controlled. Here, each of the plurality of pipelines is provided with a valve, and the amount of cooling liquid obtained by opening the valve is determined in stages by the combination of opening and closing of the valve. The number N of the combinations U is calculated by the following formula (1
). (1) However, n is the total number of valves, and r is the number of valves combined for control. Therefore, if an of the valve is 4 as shown in Figure 1, the number of combinations is 15 (16 if you include the state in which all valves are closed) from equation (1). It is possible to match. As described above, according to the present invention, accurate flow rate can be achieved by simply providing a plurality of general valves without using an expensive flow meter or an opening adjustment type flow control valve that requires visual control. Control can be performed easily and effectively. In addition, since a flow rate control valve as mentioned above is not used, there are 3B problems such as time delay associated with flow rate control, hunting phenomenon of flow rate or valve opening, and damage to equipment.
<Cavitation etc. will also occur, and a good flow rate control of 14 degrees can be achieved extremely quickly. Furthermore, by appropriately selecting the flow path area (opening surface g4) of each valve and increasing the number of valves, nearly stepless flow control can be performed over a wide range, at high speed, and with high precision. (Example) Hereinafter, an example of a cooling water Ashikaga tII device in which the nozzle supply amount control method of a controlled cooling device according to the present invention is adopted will be described in detail. This example is shown in FIG. 1 above. It has the same configuration as the conventional example shown in FIG. It has a nozzle 22 for liquid-cooled fJ
In the cooling water utilization control device that controls the water ω of the cooling water 52 supplied to the steel plate 40A, which is one shrine, the steel plate 40
A conveying row 538 for conveying A, each parallel pipe line 44A to 44D provided between the main water supply pipe 12 and the water supply branch pipe 20 to constitute an independent flow path, and the parallel pipe line 44A to An opening/closing control for combining valves 42A to 42D and selectively opening and closing the valves 42A to 420, which are provided in each valve 44D and have a function of independently opening and closing the flow passages, and have different flow passage areas. A device 46 is provided. For the cooling water supply source 10, for example, a constant pressure discharge source pump may be used to provide a constant pressure source, or a pressure reducing valve may be provided on the pump discharge side. Each of the valves 42A to 42D may have an opening with a pressure reducing function, an opening/closing function with a constant opening area, or an opening with a different flow path area. Specifically, each of the valves 42
A general ball valve equipped with a rotary actuator 47 powered by air pressure as shown in FIGS. 2(A) and 2(B) can be used for A to 42D. In addition,
2A and 2B, 48 is a valve body for opening and closing the valves 42A to 42D, and 50 has a predetermined inner diameter;
2A to 42D are fluid passage holes through which fluid passes and covers when opened. Here, when the ball valves used in the valves 42A to 42D are closed based on the opening/closing command from the +3111 device 46, the fluid passage hole 50 is in the flow path as shown in FIG. 2 (A>). When the valves 42A to 42D are open, the valve body 48 is rotated by 90 degrees by the low reactor 47, as shown in FIG. The fluid passage hole 50 is parallel to the flow path, generates a predetermined pressure drop, and allows a foot of water commensurate with the primary side pressure to pass through to the secondary side.The operation of the embodiment will be described below.Water is supplied from the water supply source 10. Parallel pipe line 44A ~ via main pipe 12
Cooling water 52 is supplied to 44D. At that time, each valve 4
2A to 42D are opened and closed by selecting a combination according to a drive signal from the opening/closing υ control device 46, and cooling water is allowed to flow from the opened valve, thereby causing the flow of the cold u1 water j to be υ1wJ. The controlled cooling water is collected in one place and sent to the water supply branch pipe 20.
is supplied from the W jetting nozzle 22 to the high-temperature steel plate 40A on the conveyor roller 38. Then, the flow rate is controlled, and the steel plate 40A is optimally water cooled.
cooled down. In this way, the cooling water port control device according to this embodiment can control the flow rate using a general ball valve as shown in FIG. It is possible to control the flow rate of cooling water with a simple configuration and at low cost without requiring a υIt211 valve with a special structure inside the valve like the flow ffl III control valve shown in the figure. Maintenance, inspection, or valve replacement of the cooling water ffl III till device can be easily performed. By the way, the cooling water can be controlled by closing each of the valves 42A to 42D of the cooling water Jut and II control devices shown in FIG. In this case, the results of actually measuring the flow of cooling water spouted from the cooling water jetting nozzle 22 will be explained below.In this case, the primary side pressure of each valve 42A to 42D (assumed to be a constant pressure) is 41cg/dG, and each valve 42A
~42D orifice diameter and cooling water flowing through it Ft6
i was set as shown in Table 1 below. Table 1 Also, each of the valves 42A to 42D is opened and closed by a rotary actuator (not shown) using air pressure, for example, as shown in FIG.
This is done quickly and automatically based on the command No. 6. The opening/closing control of each of the valves 42A to 42D was performed based on the combinations of cases A to P as shown in FIG. Then, corresponding to cases A-P of bid rigging, the flow opening of the cooling water jetted from the cooling water jetting nozzle 22 had a value as shown in FIG. 4. Also, the calculated value of the cooling water flow R calculated from the sum of the valve opening areas in each of the cases A to P is not shown in FIG. From FIG. 4, it is understood that the flow port control method according to the present invention can adjust the flow rate at high speed and with high precision, and has high practical value. Note that the measured value is based on the value of the valve 4.
The instantaneous flow ports were measured 2 to 3 seconds after the opening/closing operations of 2A to 42D, and no fluctuation in flow R over time was observed. In addition, in the embodiment described above, cooling water was used as the cooling liquid, but the cooling liquid is not limited to water, and other cooling liquids can be used depending on the purpose. Further, in the embodiment, four parallel pipe lines 44A to 4
Although an example using the respective valves 42A to 42D disposed in 4D has been described, the number of parallel pipes and the number of valves are not limited to this, and can be arbitrarily provided. In this case, by increasing the number of valves, almost stepless flow control can be performed over a wide range with high precision.

【Effect of the invention】

As explained above, according to the present invention, accuracy can be improved by simply providing a plurality of general valves without using an expensive flow gauge or a flow Gυ control valve of the opening side surface type that requires complicated control. Good control can be performed conveniently and effectively. In addition, since the flow inlet fi control valve as described above is not used, there is no time delay or hunting in the flow rate or valve opening accompanying flow R control, and there is no cavitation that can cause equipment damage. It becomes possible to realize highly accurate flow port control extremely quickly. Furthermore, the flow path area of each valve (frontage surface Fx”s)
By appropriately selecting the number of valves and increasing the number of valves, there are excellent effects such as nearly stepless flow rate control being able to be performed over a wide range, at high speed, and with high precision.

[Brief explanation of drawings]

FIG. 1 is a pipe diagram including a partial top view showing the configuration of an embodiment of a cooling water well-controlled head in which the nozzle supply liquid a control method of the controlled cooling III neck according to the present invention is adopted; Figure 2 (A> is
A sectional view of the main part showing the open state of the valve used in the embodiment,
The same figure (B) is also a sectional view of the main part showing the open state,
The figure shows an example of a combination of valves for explaining the operation of the embodiment, and FIG. FIG. 5 is a pipe diagram showing the configuration of a conventional cooling water 511JI m device, FIG. 6 is a sectional view showing the configuration of an example of a conventional cooling liquid amount control valve, and FIG. 2 is a cross-sectional view showing the configuration of another example. DESCRIPTION OF SYMBOLS 10... Water supply source, 12... Water supply main pipe, 20... Water supply branch pipe, 22... Cooling water jet nozzle, 40... Material to be cooled, 40A... Steel plate, 42A to 42D. ...Valve, 44A-44D...Parallel pipe line, 46...Opening/closing control device, 52...Cooling water.

Claims (1)

[Claims] (1) In a nozzle liquid supply amount control method for a control cooling device that directly heat-treats rolled material, a plurality of mutually independent parallel pipes leading to the nozzle are equipped with on-off valves having different flow path areas, and each valve is A method for controlling the amount of liquid supplied to a nozzle of a control cooling device, characterized in that the amount of cooling liquid is adjusted by opening and closing each valve so that the total amount of liquid passing through the nozzle becomes the amount of liquid supplied to the nozzle.