JPH10225653A - High pressure fluid jetting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the jetting time of a jetting means by providing the jetting means for jetting fluid pressurized by a pressurizing means toward an object to be treated and constituting the pressurizing means so that driving output received from a driving source is changed to control the discharge pressure of the fluid. SOLUTION: A high pressure pump 22 is connected to an output axis of a variable speed driving means 21. By controlling a load of the variable speed mechanism 20 thereof, the revolution of the high pressure pump 22 is arbitrarily changed enabling the change of discharge pressure of the high pressure pump 22. The high pressure pump 22 is connected to a spray header 7 through piping 23 on the discharge side, and the fluid discharged from the high pressure pump 22 is jetted from the spray header 7. At this time, to the variable speed mechanism 20, a controller 24 for receiving a signal from a steel detector 10 to send a signal to the variable speed mechanism 20 is connected. When high pressure fluid is jetted from the spray header 7, the discharge pressure of the high pressure pump 22 is made high, and at the time other than that, driving speed of the high pressure pump 22 is controlled so that the discharge pressure is made low.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure fluid ejecting apparatus suitable for use in, for example, a hydraulic descaling apparatus for injecting high-pressure water in order to remove surface scale during rolling of steel.

[0002]

2. Description of the Related Art A general structure of a conventional hydraulic descaling apparatus is shown in FIG. As shown in FIG.
It has a high-pressure pump 2 started by driving a constant-speed motor 1 and an accumulator 3 for absorbing load fluctuations of the high-pressure pump 2 and stabilizing a discharge pressure. Reference numeral 4 denotes a shutoff valve 5 disposed in the accumulator 3.

In this apparatus, a fluid discharged from a high-pressure pump 2 is guided into a spray header 7 via an injection valve 6, and a plurality of injection nozzles provided in the spray header 7 pressurize a steel material (object to be processed) at a high pressure. ) 8. Spray header 7 on conveying path 9 for steel 8
On the more upstream side, a steel detector 1 that detects the carry-in of the steel 8
0 is provided, and on the downstream side, a rolling mill 11 having rollers arranged vertically is provided.

This device is operated according to a flow shown in FIG. That is, after the high-pressure pump 2 is started, the discharge valve 4 and the shutoff valve 5 are sequentially opened, and the operation is ready. In this state, a timer is set when the steel material detector 10 detects the carry-in of the steel material 8, and the injection valve 6 is opened after a lapse of a certain time corresponding to a moving time from the detection position to the descaling position. The high-pressure fluid is injected from the injection nozzle of the spray header 7 toward the steel material 8, and after injection by a timer for a predetermined time, the injection valve 6 is closed.

[0005] Even when the injection valve 6 is closed in this manner, a minimum amount of fluid flows into the spray header 7 from the bypass orifice 12 installed in parallel with the injection valve 6,
Thus, the inside of the spray header 7 is filled with water.

[0006]

However, in the above conventional example, a plurality of on-off valves such as a discharge valve 4 and an injection valve 6 for supplying and shutting off high-pressure water are provided in the injection path. With the opening and closing of these on-off valves, rapid fluctuations in water volume and pressure occur, causing a so-called water hammer phenomenon in which the piping system vibrates. For this reason, as described above, it is necessary to separately provide the accumulator and its accessories and the like, which has led to an increase in complexity of the device, an increase in construction costs and an increase in installation space.

In particular, in the hydraulic descaling apparatus described above, in recent years, in order to further enhance the scale removing effect, the conventional injection pressure of about 150 kg / cm ² class has been used.
200-300 kg / cm ² or even higher pressure is required, and when the injection pressure is increased in such a manner, the above-mentioned problems have become more remarkable.

[0008] In view of the above, the present invention fundamentally changes the conventional idea to avoid the water hammer phenomenon,
It is an object of the present invention to provide a high-pressure fluid ejection device capable of controlling ejection of a high-pressure fluid without using an on-off valve.

[0009]

According to a first aspect of the present invention, there is provided a pressurizing means which is driven by a driving source to discharge a fluid, and a jetting means which jets the pressurized fluid toward an object to be processed. Wherein the pressurizing means is capable of controlling the fluid discharge pressure by changing a drive output received from the drive source.

According to the present invention, the high-pressure fluid is supplied to the injection means only when necessary and is injected from the injection means via the variable pressure generation means. Can be supplied to the injection means, whereby the injection time of the injection means can be controlled without using an injection valve.

According to a second aspect of the present invention, there is further provided a control means for controlling the discharge pressure of the pressurizing means in at least two stages based on an output signal of the detecting means. The high-pressure fluid ejection device according to claim 1, further comprising:

According to a third aspect of the present invention, the driving source includes:
2. The high-pressure fluid ejection device according to claim 1, comprising a constant speed motor and a variable speed mechanism. The invention according to claim 4 is the high-pressure fluid ejection device according to claim 1, wherein the drive source is configured by a variable speed motor.

According to a fifth aspect of the present invention, the discharge port of the pressurizing means is directly connected to the fluid supply port of the jetting means via a pipe. Device. Here, "directly connected" means "there is no flow control valve", and therefore, this piping is always an open passage. As a result, even if the pump is in the shut-off operation, no trouble occurs due to the temperature rise.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a semiconductor device having two different pressures.
2. The high-pressure fluid ejecting apparatus according to claim 1, comprising two fluid supply sources, wherein a high-pressure supply source is used during ejection, and a low-pressure supply source is used during non-ejection. Thereby, the pressure and the flow rate in the injection path at the time of non-injection are further reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which a high-pressure fluid ejection device according to the present invention is used in a hydraulic descaling device will be described below with reference to FIGS. Note that the same members as those of the conventional example shown in FIG.

As shown in FIG. 1, the high-pressure pump 22 includes:
The output shaft of a variable speed driving means 21 composed of the constant speed motor 1 and the variable speed mechanism 20 is connected. This allows
By controlling the load of the variable speed mechanism 20 interposed in series between the constant speed motor 1 and the high pressure pump 22, the rotation speed of the high pressure pump 22 is reduced, for example, by 20 to 100%.
, The discharge pressure of the high-pressure pump 22 can be changed.

The discharge side of the high-pressure pump 22 is directly connected to the spray header 7 having a plurality of injection nozzles via a pipe 23 without using an on-off valve such as an injection valve. Accordingly, the fluid discharged from the high-pressure pump 22 is directly supplied into the spray header 7 through the pipe 23, and if the pipe loss from the discharge port of the high-pressure pump 22 to the spray header 7 is ignored, the discharge pressure of the high-pressure pump 22 is reduced. And acts directly on the inside of the spray header 7.

The variable speed mechanism 20 receives a signal from the steel detector 10 for detecting the steel material 8 as an object to be processed, which is sent along the conveying path 9, and receives the signal from the variable speed drive means 21. A controller 24 for sending a control signal to 20 is connected.

The variable speed mechanism 20 sets the discharge pressure of the pump 22 to a predetermined high pressure when the high-pressure fluid is jetted from the jet nozzle of the spray header 7 toward the steel material 8 based on a control signal from the controller 24. At other times, the driving speed of the high-pressure pump 22 is controlled so as to be a predetermined low pressure.

Next, the operating state and operation of the hydraulic descaling apparatus according to this embodiment will be described with reference to FIGS. First, the high-pressure pump 22 is started, and the variable speed mechanism 2 is started.
The 0 and allowed to rotate for example a low speed rotational speed N ₁ shown in FIG. 3 (minimum speed). At this time, a fluid having a discharge pressure H ₁ and a flow rate Q ₁ shown at a point a in the drawing is supplied to the spray header 7 in relation to the resistance curve of the pump.

Next, when the steel detector 10 detects the carry-in of the steel 8, the detection signal is sent to the controller 24,
Outputs a control signal to increase the rotation speed from N ₁ to a predetermined rotational speed N ₂ of the high-pressure pump 22 to the variable speed mechanism 20.

As a result, the number of revolutions increases, and accordingly,
The discharge pressure and flow rate of the high-pressure pump 22 is increased gradually toward the point a to the point b, and finally the required pressure in the rotational speed N _2, for example, 200 kg / cm ² and a predetermined flow rate of fluid to the spray header 7 Supplied. Here, the final rotational speed N ₂ is set to a constant, the rotational speed N ₂ is variable, it may be controlled in accordance with the detected value of the input or sensor manual.

Since there is no injection valve or the like between the high-pressure pump 22 and the spray header 7, the discharge pressure of the high-pressure pump 22 directly acts on the spray header 7, for example, 200 kg / cm.
^At the injection pressure of ² , high-pressure water is injected toward the steel material (workpiece) 8. This injection is continued for a predetermined time during which the steel material is at the descaling position by a timer built in the controller 8 or the like.

After the set time of the timer elapses, the controller 2
4 the control signal is sent to the variable speed mechanism 20 from variable speed mechanism based on the control signal 20 lowers the rotational speed of the high-pressure pump 22 from N ₂ to the low-speed rotational speed N _1. Thus, the fluid of the minimum flow Q ₁ is supplied to the spray header 7, and flows out from the injection nozzle. In this device, since the pipe 23 is always an open passage, even if the pump 22 is in a shut-down operation, no trouble occurs due to a rise in temperature.

In the above description, the driving source of the pressurizing means is constituted by the combination of the constant speed motor and the variable speed mechanism. However, the driving source may be a motor having a variable speed by, for example, inverter control.

FIG. 4 shows a second embodiment of the present invention. In this embodiment, a low-pressure water source line 32 is provided in addition to a medium-pressure water source line 31 normally used as a water source. This is switched and used. The medium pressure line 31 is connected to the high pressure pump 2
The low pressure line 32 is connected to the high pressure pump 22 via a check valve 34. Such a low-pressure line may be provided, for example, with a small water tank separately from a larger medium-pressure water tank.

The operating state and operation of the hydraulic descaling apparatus of this embodiment will be described with reference to FIGS. First, to start the high-pressure pump 22 in the closed state of the medium pressure line off valve, allowed to rotate at a slower rotational speed N ₁ (lowest speed) by the variable speed mechanism 20. At this time, since the low pressure line is connected, the fluid having the discharge pressure H ₀ and the flow rate Q ₀ shown at the point c in FIG. 3 is supplied to the spray header 7.

Next, when the steel detector 10 detects the carry-in of the steel 8, the detection signal is sent to the controller 24,
Opens the on-off valve 33 and connects the medium pressure line. Then, the operating point moves from the point c on the resistance curve to the point a, and the fluid having the discharge pressure H ₁ and the flow rate Q ₁ is supplied to the spray header 7. Next, the controller 24 outputs a control signal to increase the rotation speed of the high-pressure pump 22 from N ₁ to a predetermined rotational speed N ₂ to the variable speed mechanism 20. As a result, the rotation speed increases, and the discharge pressure and the flow rate of the high-pressure pump 22 gradually increase from the point a to the point b, and finally reach a required pressure at the rotation speed N ₂ , for example, 200 kg / cm ^2. A flow of fluid is supplied to the spray header 7.

After the set time of the timer has elapsed, the controller 2
4 the control signal is sent to the variable speed mechanism 20 from variable speed mechanism based on the control signal 20 lowers the rotational speed of the high-pressure pump 22 from N ₂ to the low-speed rotational speed N _1. Further, the controller 24
Closes the on-off valve 33 and connects the low pressure line 32.
Then, the operating point moves from the point a to the point c on the resistance curve,
A minimum flow rate fluid having a discharge pressure H ₀ and a flow rate Q ₀ is supplied to the spray header 7. Therefore, in this embodiment, in the state where there is no injection from the nozzle, the pressure in the injection path becomes lower, and advantages such as prolongation of the life of the apparatus, reduction of noise, and saving of water can be obtained.

[0030]

As described above, according to the present invention,
It is possible to control the injection of the high-pressure fluid from the injection means without using the injection valve, thereby completely eliminating the occurrence of the water hammer phenomenon and keeping the worker and the surrounding environment favorable, The accumulator and its associated equipment can be omitted, and the equipment cost can be reduced, the installation space can be reduced, the device can be simplified, and the demand for higher pressure can be met.

Further, when the injection is not performed, the high-pressure pump is decelerated to reduce the driving energy or to switch to a low-pressure line to prevent the injection path from being constantly exposed to the high pressure. It is possible to extend the life and reduce noise.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is also an operation flowchart.

FIG. 3 is a graph conceptually showing a difference when a rotation speed is changed in a characteristic curve diagram of a pump.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is also an operation flowchart.

FIG. 6 is a diagram showing a conventional example.

FIG. 7 is also an operation flowchart.

[Explanation of symbols]

 Reference Signs List 1 constant speed motor 8 steel material (workpiece) 7 spray header (injection means) 20 variable speed mechanism 21 variable speed drive means 22 high pressure pump (variable pressure generation means) 24 controller 31 medium pressure line 32 low pressure line

Claims (6)

[Claims] 1. A pressurizing means driven by a drive source to discharge a fluid, and a jetting means for jetting the pressurized fluid toward an object to be processed, wherein the pressurizing means receives from the drive source. A high-pressure fluid ejection device characterized in that a fluid discharge pressure can be controlled by changing a drive output. 2. The apparatus according to claim 1, further comprising: means for detecting an object to be processed; and control means for switching and controlling the discharge pressure of said pressurizing means in at least two stages based on an output signal of said detecting means. The high-pressure fluid ejection device according to claim 1. 3. The high-pressure fluid ejection device according to claim 1, wherein the drive source comprises a constant speed motor and a variable speed mechanism. 4. The high-pressure fluid ejection device according to claim 1, wherein the drive source is constituted by a variable speed motor. 5. The high-pressure fluid ejection device according to claim 1, wherein a discharge port of the pressurizing unit is directly connected to a fluid supply port of the ejection unit via a pipe. 6. The method according to claim 1, further comprising two fluid sources having different pressures.
The high-pressure fluid ejection device according to claim 1, wherein a high-pressure supply source is used during injection, and a low-pressure supply source is used during non-injection.