JPH09225345A - Fluid injection nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To open and close a valve body of high response by a method wherein in a fluid jet nozzle which is used in a case of cooling by jetting cooling water in threading a bloom or the like, a piston which is driven by closing the valve body with a fluid medium of hydraulic fluid or the like and by compressing that is equipped to a nozzle head itself. SOLUTION: When an electric current is not conducted to coils 6a, 7a, a piston 5 can be freely moved. Thereby, a valve body 3 receives hydraulic pressure of cooling water running toward a jet nozzle 1a from a header pipe 2 to be kept at an opened valve position, and cooling water is jetted from the jet nozzle 1a. Then, when a current is conducted to the coil 6a, 7a, since electromagnets 6, 7 repel each other, the electromagnet 6 fixed to the piston 5 moves downward to compress hydraulic fluid H. Then at a point of time when pressure of the hydraulic fluid H is increased, and the piston 5 reaches a stroke end, a cone part at a tip of the valve body 3 is seated on a valve seat 1b to close a passage of cooling water, and jetting of cooling water from the jet nozzle 1a is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid injection nozzle for injecting, for example, cooling water, and in particular, it has an extremely simple structure for injecting and stopping and has a high responsiveness. Control mechanism for.

[0002]

2. Description of the Related Art For example, in a rolling mill, when a steel strip is passed between rolls, cooling water is jetted by a nozzle on the inlet side and the outlet side to cool the steel strip. The nozzles are arranged as a plurality of sets above and below the pass line, and a plurality of nozzles are generally arranged in the width direction of the pass line.

As a mechanism for injecting and stopping the injection fluid from the nozzle, there is, for example, one in which an electromagnetic valve for opening and closing is incorporated in the fluid supply passage, but in the nozzle for cooling the billet provided in the rolling mill. Since the injection pressure of the cooling water is considerably high, it is already known to close the valve by fluid pressure drive.

FIG. 3 is a diagram showing an outline of such a cooling nozzle for a rolling mill driven by fluid pressure.

This cooling nozzle is provided with a nozzle head 1 arranged to inject cooling water in the pass line direction of the steel plate, and a header pipe 2 connected to the base end of the nozzle head 1 and communicating with a cooling water supply source. It is a thing. An injection hole 1a is formed at the tip of the nozzle head 1 and an annular valve seat 1b is provided on the upstream side thereof.
And a bypass passage 1c that connects the header pipe 2 with the flow passage. The valve body 3 for opening and closing the flow path to the injection hole 1a is movably incorporated.

The valve body 3 is watertightly incorporated in a bore 1d formed in the nozzle head 1, and the bore 1d is a hydraulic unit 1 for urging the valve body 3 in the valve closing direction.
Connected to 0. The hydraulic unit 10 has a general hydraulic circuit, and includes a hydraulic pump 10a and a tank 1.
0b and a switching valve 10c are provided.

In the state of FIG. 3, the working fluid is the tank 10b.
Is switched to the side by the switching valve 10c, and the valve body 3
The force that pushes in the valve closing direction is not activated. Therefore, when the injection fluid is supplied from the header pipe 2, the valve body 3 is pushed by the pressure of the injection fluid in a direction away from the valve seat 1b as shown in the figure, and thereby the valve open state is maintained. When the switching valve 10c is switched as shown in FIG. 4, the hydraulic oil is supplied to the bore 1d by the hydraulic pump 10a, and the pressure of this working fluid is set higher than the supply pressure of the injection fluid, so that the valve body 3 is opened. The valve can be closed by pushing in the direction of the valve seat 1b.

[0008]

However, since the working fluid is a compressible fluid and air may be mixed therein, the hydraulic fluid is pumped by the hydraulic pump 10a into the bore 1d.
The response time of the movement of the valve body 3 when supplying the gas varies depending on the air content. On the other hand, in the equipment in which the plurality of nozzle heads 1 are arranged in the width direction of the pass line, it is required that the respective jetting and stopping times are simultaneously activated. Therefore, it is necessary to appropriately control the valve closing speed for each nozzle, but in the case of using the hydraulic unit 10, there is a difference in the response time of the valve element 3 as described above, and thus such optimum control is performed. In order to execute, the expansion of the control system is required.

Further, in equipment such as a rolling mill in which a large vibration is generated when the steel piece is bitten, not only the threading but also the reverse of the steel piece is frequently performed.
Large vibrations are transmitted not only to the header pipe 3 and the pipe to the hydraulic unit 10. Therefore, not only the nozzle but also the pipe are required to have sufficient strength.

However, not only the cooling nozzle but also various devices are installed in a disordered state in the portions of the rolling mill between which the pass line is sandwiched vertically, so that interference between the piping and other devices can be avoided. Absent. For this reason, the degree of freedom in design for installing the piping and each device is considerably reduced, and
There is also a problem that assembly work and maintenance inspection are troublesome. Then, if the volume (length, diameter) of the pipe to the hydraulic unit 10 is large, the flow rate of the working fluid also increases, and the compression ratio also increases in proportion to this increase,
The response time is further extended, and the obstacle in terms of control increases.

As described above, in the nozzle that closes the valve body using the conventional hydraulic unit, the control of fluid injection from the nozzle may be poor due to the difference or extension of response time, and the piping space cannot be secured. There's a problem.

The problem to be solved in the present invention is to provide a fluid injection nozzle which optimizes the closing of the valve body without causing a difference or extension in response time, and also reduces ancillary piping so as not to interfere with peripheral equipment. To do.

[0013]

SUMMARY OF THE INVENTION According to the present invention, a valve seat is formed in the middle of an internal flow path of a nozzle head, and a bore facing the valve seat is provided so that the valve seat can be seated. A valve body is provided movably in the bore by the pressure of the fluid toward the injection hole at the end of the flow path of the head, and a chamber communicating with the bore and having a piston incorporated therein is integrally formed with the nozzle head. Then, a working fluid is sealed between the end surface of the valve body located in the bore and the piston, and the piston and the chamber are connected by magnetic force generating means that are attracted and repelled from each other by energization. The working fluid can be compressed when the magnetic force generating means repulses between the piston and the chamber.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION When the piston repels the chamber by the magnetic force generating means to compress the working fluid, the pressure of the working fluid is increased and the valve body facing this working fluid is directed toward the direction from the bore, that is, toward the valve seat side. Be energized. Therefore, if the pressure of the working fluid is set to be higher than the pressure of the injection fluid passing through the internal passage of the nozzle head, the valve body can be seated on the valve seat to close the passage of the injection fluid. it can.

Further, when the flow path is closed, if the magnetic force generating means is operated in such a direction that the piston and the chamber are attracted to each other, the piston moves so as to widen the space between the piston and the chamber, and the working fluid is moved. Pressure drops. Therefore, when the working fluid becomes smaller than the pressure of the injection fluid, the valve body moves to the inner side of the bore by the pressure of the injection fluid and separates from the valve seat, and the flow path of the injection fluid is opened.

[0016]

1 is a longitudinal sectional view showing a main part of a fluid injection nozzle of the present invention, which is used for cooling a steel slab incorporated in a rolling mill as described in the prior art. .

In the figure, in the same manner as in the conventional example, a nozzle head 1 having an upper end connected to a header tube 2 is formed with an injection hole 1a, a valve seat 1b, a bypass passage 1c and a bore 1d, and this bore 1d is formed. A valve body 3 having a cone-shaped surface facing the valve seat 1b side is movably provided. The valve body 3 is provided with a sealing material 3a such as an O-ring on its peripheral surface,
The d side and the flow path side of the cooling water are sealed.

A chamber 4 communicating with the bore 1d is integrally provided on the peripheral surface of the nozzle head 1. The chamber 4 has a circular opening cross-section together with the peripheral surface of the nozzle head, and accommodates a piston 5 movably in a watertight manner inside the chamber and a flow path between the piston 5 and the valve body 3. Is filled with a working fluid H. The working fluid H is injected by a fixed amount from a filling port 4a opened in the peripheral wall of the chamber 4 to remove air, and then sealed by a plug 4b screwed into the filling port 4a.

Further, an electromagnet 6 is integrally fixed to the upper surface of the piston 5, and an electromagnet 7 facing the electromagnet 6 on the piston 5 side is also provided on the inner circumference of the upper end of the chamber 4. These electromagnets 6 and 7 are coils 6a and 7a around them.
The wirings 6b and 7b to the wiring are connected from a control unit (not shown), and these wirings 6b and 7b are covered with a heat-proof cover in order to eliminate the heat effect from the steel slab. The control unit controls injection and stop of cooling water from the nozzle head 1, and controls the energization of the coils 6a and 7a so that the electromagnets 6 and 7 can be set to have opposite magnetism or the same magnetism. Is.

In the above construction, when the coils 6a and 7a are not energized, neither attraction nor repulsion acts between the electromagnets 6 and 7, so that the piston 5 can move freely. Therefore, as shown in FIG. 1, the valve body 3 receives the hydraulic pressure of the cooling water flowing from the header pipe 2 toward the injection hole 1a, and displaces the piston 5 to the position where the piston 5 is raised by the working fluid. As a result, the valve body 3 is held in the valve open position by the water pressure, and the cooling water is jetted from the jet hole 1a toward the steel slab.

When stopping the injection of the cooling water, the controller controls the energization of the coils 6a and 7a so that the electromagnets 6 and 7 have the same magnetic pole. As a result, the electromagnets 6 and 7 in the state of FIG. 1 repel each other, so the electromagnet 6 fixed to the piston 5 is pushed downward at a stroke and moves,
The working fluid H sealed between the valve body 3 and the valve body 3 is rapidly compressed. Therefore, the pressure of the working fluid H rises,
Finally, when the pressure of the working fluid H becomes higher than the water pressure of the cooling water and the piston 5 reaches the stroke end at the lower end of the piston 5, as shown in FIG. And the cooling water flow path is closed, and the injection hole 1a
The injection of cooling water from is stopped. And coil 6
This injection stop is maintained by continuing to energize a and 7a.

When restarting the injection of cooling water,
The energization to the coils 6a and 7a is controlled by the control unit so that the electromagnets 6 and 7 in the state of FIG. 2 have different magnetic poles. As a result, the electromagnets 6 and 7 are attracted to each other, and the piston 5 rises together with the electromagnet 6 to join the electromagnets 6 and 7 as shown in FIG. Due to the rise of the piston 5 as described above, the pressure of the working fluid H between the piston 5 and the valve body 3 is reduced, and finally the hydraulic pressure of the cooling water is increased to restore the valve open state of FIG.

Thus, the coils 6a, 7 of the electromagnets 6, 7 are
Only by controlling the energization of a, it is possible to raise and lower the pressure of the working fluid H in the flow path with the valve body 3, and to open and close the valve body 3 depending on the relationship with the water pressure of the cooling water. The valve can be operated. In this opening / closing operation, the working fluid H is not supplied from the hydraulic unit as in the conventional example, but is a small amount enclosed in the space closed by the bore 1d and the chamber 4, so that the piston is particularly closed during the valve closing operation. Even when 5 compresses the working fluid H, the response time of the movement of the valve body 3 in the valve closing direction becomes extremely short. Further, if the working fluid H is injected from the filling port and sufficiently deaerated in the initial state when it is sealed by the plug 4b, this initial state is maintained thereafter. Therefore, the working fluid H
It is possible to eliminate the difference in response time and to shorten the response time by preventing the air from entering the inside.

Further, a chamber 4 is provided on the peripheral surface of the nozzle head 1.
Since it is a bulky structure that only needs to be provided and only the wirings 6b and 7b are exposed to the outside, the hydraulic unit 10 as in the conventional example is used.
No piping is required between and. Therefore, even when incorporated in a rolling mill, interference with peripheral equipment can be avoided, complicated piping can be provided, and troublesome maintenance and inspection can be avoided. In particular, since the assembly is remarkably simplified by eliminating the piping, the wirings 6b and 7b can be freely bent and circulated, so that the degree of freedom in the layout of peripheral devices is also improved.

Although the combination of the electromagnets 6 and 7 is used in the embodiment, for example, the permanent magnet may be fixed to the piston 5 and the electromagnet may be attached to the chamber 4 side, or the opposite arrangement may be adopted. Similarly, the valve body 3 can be opened and closed by controlling the energization of the coil.

It is needless to say that the present invention can be applied not only to the nozzle for cooling water incorporated in the rolling mill but also to the nozzle for ejecting air or other fluid.

[0027]

According to the present invention, since the nozzle head itself is provided with a fluid medium such as working fluid and a piston for closing and driving the valve body by compressing the fluid medium, it is possible to open and close the valve body with high responsiveness. Therefore, for example, when cooling water is used as the injection fluid, the cooling of the cooling target is optimized.

Further, since it is unnecessary to supply and discharge the fluid medium from the external unit as in the conventional case, the interference with the equipment around the nozzle can be avoided, and the degree of freedom of the arrangement of the nozzle itself and the peripheral equipment can be improved. Assembly and maintenance inspection will be much easier.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view of an essential part of a fluid injection nozzle according to an embodiment of the present invention when a valve body opens a flow path.

FIG. 2 is a schematic vertical cross-sectional view of a main part of the fluid injection nozzle of FIG. 1 when a valve body closes a flow path.

FIG. 3 is a schematic vertical cross-sectional view of a main part when a valve body is open in a conventional example including a hydraulic unit.

4 is a schematic vertical sectional view of the nozzle of FIG. 3 when the valve body closes the flow path.

[Explanation of symbols]

 1: Nozzle head 1a: Injection hole 1b: Valve seat 1c: Bypass passage 1d: Bore 2: Header pipe 3: Valve body 3a: Seal material 4: Chamber 4a: Filling port 4b: Plug 5: Piston 6: Electromagnet 6a: Coil 7: Electromagnet 7a: Coil 10: Hydraulic unit 10a: Hydraulic pump 10b: Tank 10c: Switching valve H: Working fluid

Claims (1)

[Claims] 1. A valve seat is formed in the middle of an internal flow passage of a nozzle head, and a bore that is cut off from the internal flow passage is provided on the upstream side facing the valve seat so that it can be seated on the valve seat. The nozzle head is provided with a valve body that is movable in the bore by the pressure of the fluid toward the injection hole at the end of the flow path of the nozzle head, is movable to the bore, and is connected to the bore and has a chamber in which a piston is incorporated. In preparation for this, a working fluid is sealed between the end face of the valve body located in the bore and the piston, and the piston and the chamber are connected by a magnetic force generating means that is attracted and repelled by energization. And a fluid injection nozzle capable of compressing the working fluid when the magnetic force generating means repulses between the piston and the chamber.