JPS58185716A - Dewatering method of cooler - Google Patents

Abstract

PURPOSE:To perform dewatering of a laminar nozzle automatically, quickly and exactly, by closing an automatic sluice value of a water supply pipe when cooling of a material ends, and opening an automatic drain valve of a nozzle header to drain a specified volume of cooling water then closing the drain valve. CONSTITUTION:An automatic sluice valve 23 is opened during cooling of a steel material 40 or the like, and the flow rate of water supply is controlled according to the required ejection rate of cooling water with a flow rate control device 22. When the cooling of the material 40 ends, a control device 60 closes the valve 23 instantaneously and opens an automatic drain valve 52 of a drain piping 50 simultaneously. The control device closes the valve 52 immediately when the specified volume of the cooling water in a nozzle header 21 is drained after a specified time. The dewatering of the laminar flow nozzle is accomplished automatically and quickly at a desired point of time by the above-mentioned method. The dropping of the cooling water from the laminar flow nozzle after the stoppage of the water supply ceases quickly in about <=(2-3)sec.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for draining a laminar 70-nozzle with a rod-shaped water stream for cooling hot rolled steel materials and the like.

One end of the inverted U-shaped tube is connected to the nozzle header, and cooling water is jetted downward from the other end of the inverted U-shaped tube, or cooling water is dropped onto the surface to be cooled using the siphon tube principle to cool steel materials, etc. The laminar flow cooling system can maintain a large cooling capacity even when the distance between the surface to be cooled and the nozzle outlet (nozzle width) increases, thereby preventing damage to the nozzle due to deformation of the material to be cooled. It is widely used for continuous cooling of steel materials on hot run tables and plate mill lines.

When using a laminar flow nozzle, stopping the cooling water is as follows:
This is done by stopping the water supply to the nozzle header, but even if the water control valve in the water supply pipe is completely closed, air will not fill up from the U-shaped pipe where the siphon effect has been established until the U-shaped pipe is filled with air. Water continues to be discharged and the nozzle cannot be drained instantly. For this reason, when hot steel materials that do not require water cooling pass under the cooling device immediately after cooling, the U-shaped tube receives the ZJV source. , dripping, cooling, and public cooling, resulting in a significant drop in quality.

Furthermore, if the nozzle is threaded after the water has been completely drained, the production efficiency will decrease, which is not preferable.

Conventionally, in order to drain the nozzle water, as shown in FIG. 1, another laminar 70-nozzle 3 is provided at one end of the nozzle header 1, which has a long vertical straight pipe section extending from the U-shaped laminar flow nozzle 2 toward the surface to be cooled. After the water supply is stopped, a part of the cooling water in the nozzle header l is drained from this nozzle 3 by taking advantage of the fact that the siphon effect of this nozzle 3 is larger than that of other nozzles 2, and the cooling water droplets from other nozzles 2 are drained. Methods were used to prevent water from drying out, but complete drainage was not always carried out.

Also, as shown in Fig. 2, connect the air pipe 10 to the middle of the U-shaped laminar nozzle 3 2, and after stopping the water supply to the nozzle header 1, connect the air pipe 10 to each U-shaped laminar flow nozzle 2. There is a method of opening a valve 11 provided in the middle of 10 and supplying compressed air to eliminate the siphon effect and drain water.

In this method, since the air pipe 12 is connected in the middle of the nozzle 0-shaped pipe 2, there is a drawback that the flow of cooling water in the nozzle is disturbed and a predetermined laminar flow cannot be obtained. If the sealing performance of the provided valve 11 is impaired, the predetermined laminar flow cannot be obtained uniformly as described above, causing uneven cooling and causing serious losses. Furthermore, air piping 10 must be connected to each U-shaped nozzle, leading to an increase in the manufacturing cost of the cooling device.

The present invention solves the above-mentioned conventional problems and provides a method for draining a laminar flow nozzle that can instantly drain water and instantly start discharging water.

The details of the method of the present invention will be explained below in accordance with the system diagram of an embodiment shown in FIG.

In the method of the present invention, an automatic water control valve 23 is provided in the middle of the water supply pipe 24 connected to the nozzle header 21 of the laminar flow nozzle, and a drain pipe 50 having an automatic drain valve 52 is attached to the nozzle header 21. At the same time as closing the automatic water control valve 23, opening the automatic drain valve 52 marked with #,
This method of draining water from a laminar flow cooling device is characterized in that the automatic drain valve 52 is immediately closed after a certain amount of cooling water in the nozzle header 21 is discharged.

As shown in FIG. 3, in the method of the present invention, a control device 60 controls an automatic water control valve 23 and an automatic drain valve 52 to drain water. When the steel material 40 is being cooled, the automatic water control valve 23 is opened and the water supply is adjusted automatically or manually by the flow rate regulator 22 according to the required amount of cooling water. At this time, the automatic drain valve 52 provided in the middle of the drain pipe 50 is closed.

After cooling the steel material 40, the cooling water 30 is discharged from the nozzle 25.
To stop the ejection of water, a stop signal is input to the control device 60, and the control device 60 instantly closes the automatic water control valve 23 and simultaneously opens the automatic drain valve 52. After maintaining this state for a certain period of time and discharging a certain amount of cooling water in the nozzle header 21, the automatic drain valve 52 is immediately closed.

The time period for which the automatic drain valve 52 is kept open is set in a timer built into the control device 60. This setting time is
This is the time required for the amount of cooling water discharged from the drainage pipe to reach the point that eliminates the siphon effect of the laminar flow nozzle. This set time is proportional to the total internal volume of the laminar flow nozzles 25 attached to the nozzle header 21 and inversely proportional to the drainage speed of the drainage pipe 50. Third
In the illustrated example, the water level of the cooling water 30 in the nozzle header 21 at which the siphon effect of the laminar flow nozzle 25 disappears is indicated by LL. The set time for which the automatic drain valve 52 is left open is given to the control device 60 according to the internal volume of the laminar flow nozzle 25, the drain speed of the drain pipe 50, etc.
This set time can be changed arbitrarily. Of course, it is also possible to use a delay circuit in place of the timer.

The water level in the discharge Ijk header from the drainage pipe 50 is L-
The reason why it is determined to be L is to enable instantaneous resumption of cooling water discharge.

The automatic water control valve 23 and the automatic drain valve 52 are preferably operated by air or hydraulic pressure, and must have a short operating time and no response delay. This allows water to be drained in 9 seconds.

It is desirable that the discharge port 51 of the drainage pipe 50 is opened to the atmosphere and opened at a lower position as far as possible, so that the difference in water head with a part of the nozzle header is increased.

The system diagram in FIG. 4 shows another embodiment of the method of the present invention, in which the discharge of a certain amount of cooling water in the nozzle header 21 is performed without using a timer or delay circuit to detect the water level in the nozzle header. The papermaking is controlled by a water level gauge 70. A water level detection signal from the water level gauge 70 is electrically input to the control device 60. In this way, the automatic drain valve 52 can be directly closed to stop drainage at the predetermined water level LL, without relying on indirect water flow measurement using a timer or delay circuit.

By the method of the present invention, the laminar flow nozzle can be drained automatically and quickly and accurately at a desired time,
After stopping the water supply, cooling water drips from the laminar flow nozzle at 2
It can be stopped in a short time of ~3 seconds or less.

Furthermore, with the method of the present invention, the drain valve can be closed with only a minimum fixed amount of water drained, so when restarting cooling, cooling water can be spouted from each laminar flow nozzle instantly and accurately. It is possible to improve cooling and work efficiency.

Since the nozzle drains instantly, uneven cooling of the steel material due to cooling water dripping from the nozzle can be eliminated, which greatly contributes to quality improvement.

[Brief explanation of drawings]

Figure 1 (a) is a conventional laminar flow nozzle drainer and device, (b) is its A-A view, and Figure 2 (a) is another conventional drainer and (b) is its B-B. It is an arrow view. FIGS. 3 and 4 are system diagrams showing an embodiment of the method of the present invention. 1-... Nozzle header 2... Laminar flow nozzle 3... Another laminar flow nozzle having a long vertical vertical pipe section 10-- Air piping 11... Air valve 12... Empty fi supply pipe 21-・・Nozzle header 22・・Flow rate adjustment device 23・・・Automatic water control valve 24・・・Water supply piping 25・・・・Laminar flow nozzle

Claims (1)

[Claims] 1. An automatic water control valve is provided on the water supply pipe connected to the nozzle header of the laminar flow nozzle, and a drainage pipe with an automatic drain valve is attached to the nozzle header.
The automatic drain valve is opened at the same time as the automatic water control valve is closed, and the automatic drain valve is closed immediately after a certain amount of cooling water in the ladder is discharged to the nozzle.
How to drain water from laminar flow cooling equipment.