JPS6041586A - Method and device for cleaning inside of piping by utilizingshock wave - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for cleaning the inside of a pipe using shock waves, which makes it possible to clean the inside of a pipe within a short period of time, and a cleaning device therefor.

[Technical background of the invention and its problems] In general, when the piping of a hydraulic control system is used as a control plate, the inside of the piping gets dirty and accumulates on the internal walls of the piping, which obstructs smooth control by hydraulic pressure. Therefore, cleaning work, so-called flushing work, is required.

Conventionally, this type of cleaning work involves a high-pressure pump that passes lashing oil (hydraulic oil) through the piping at high speed and under high pressure when the hydraulic control piping system is being reassembled. This is done by trapping various foreign substances that remain or adhere to the inside.

In this conventional method, foreign particles that are smaller than the mesh of the filter or strainer are not captured, and in practice, even foreign particles that are larger than the mesh of the flushing oil at high pressure and high speed often pass through without being captured. It was a situation where

Moreover, with this method, foreign matter hidden in recesses inside the piping, such as inside valves and fittings in the piping system, can only be removed by peeling off the phosphate film or black dyed film applied to the inner surface. However, it has not been possible to completely remove the so-called latent foreign substances that separate easily.

This is because the conventional flushing method circulates the flushing oil through the piping system under high pressure and high speed, and during this circulation, the oil becomes turbulent, which increases the viscous force and Reynolds stress, which increases the frictional force inside the pipe. The aim of this method was to remove foreign matter trapped inside the pipe by the frictional work of the oil, but in general, oil has an extremely high kinematic viscosity coefficient and high speed, so even if it flows through the pipe, the Reynolds number will not increase much, and as a result, turbulence is expected. The situation is that it is rarely done. Furthermore, high pressure is applied to increase the speed, but this has the opposite effect of causing foreign matter to stick.

For this reason, the cleaning efficiency is low, and the cleaning WR work using this method has been carried out by repeatedly circulating and rotating the flushing oil continuously over a long period of time ranging from several days to several days.

Another method is to manually apply a hammer blow from the outside and use the resulting vibration to remove the problem, but due to the structure of the pipe holding structure, the vibration is only transmitted locally.
Although effective, it was in a situation where it was impossible to achieve any effect as it required manpower and time.

By using the conventional method of rotating and circulating the high-speed, high-pressure cleaning oil mentioned above, it is possible to completely remove latent foreign substances such as foreign substances hidden in joints and other parts of the piping system, as well as potential foreign substances such as anti-rust coatings, even after long-term operation. As a result, geometric problems often occur when the piping system is connected to the main body of the hydraulic equipment and actual operation begins.

On the other hand, in recent years, automatic control using electronic control methods has become widely used in hydraulics, and when a latent foreign object becomes apparent and moves within the piping system, it can interfere with the high-precision operation of hydraulic servo valves. Due to the current situation where many accidents occur, there has long been a desire for a cleaning method or cleaning device that can efficiently and sufficiently remove latent foreign matter such as foreign matter hidden in recesses and anti-rust coatings.

[Purpose of the Invention] The present invention has been made in view of the above-mentioned points, and is capable of removing not only foreign matter lurking on the inner surface of pipes, recesses, etc., but also latent foreign matter such as rust-preventing coatings. An object of the present invention is to provide a method and device for cleaning the inside of a pipe using 11ν waves that can sufficiently clean the inside.

[Summary of the Invention] The cleaning method using shock waves of the present invention generates shock waves by rapidly closing a shutoff valve provided on the outlet side of fluid discharged or sent out into piping, Foreign matter can be removed in a short time by striking the inner surface of the pipe with the shock wave.

The cleaning device using III shock waves of the present invention includes a discharge means for discharging or sending fluid into a pipe, and a shutoff valve that can be closed rapidly and is provided on the side where the liquid is discharged through the pipe. The shutoff valve is closed to generate a shock wave, and the shock wave hits the inner wall of the pipe, thereby making it possible to remove foreign matter within the pipe in a short time.

[Embodiments of the invention] Hereinafter, the present invention will be specifically described with reference to the drawings.

1 to 5 relate to one embodiment of the present invention, FIG. 1 shows a schematic configuration of a hanging device used in the hanging method, and FIG. Using the cleaning method of
An experimental example is shown in which a cleaning device for cleaning and equipment for measuring the impact pressure generated during cleaning are installed. 4 shows the structure of the sampling piece in FIG. 3, and FIG. 5 shows the measurement results of shock wave pressure in the experimental example shown in FIG. 3.

As shown in FIG. 1, a cleaning device 1 used in the cleaning method of the present invention includes a pump 5 that uses a hose 2 or the like to discharge oil from an oil tank 3A to the piping 4 side to be cleaned; A shutoff valve 8 is attached to the end of the piping 4 through which oil is returned to the oil tank 3B via a hose 6, etc., and whose opening and closing can be controlled by a timer 7, etc., and a pump 511 is installed when the shutoff valve 8 shuts off.
The check valve 9 is attached to the discharge side end of the pipe 4 to prevent oil from flowing into the pipe 11J, and the check valve 9 also contributes to the formation of surge pressure together with the above-mentioned shutoff valve 8.

The cutoff valve 8 is formed of, for example, an electromagnetic valve, and is erected so that it can be opened by energizing it.

The cleaning method of the present invention using the cleaning device M1 is performed as follows.

That is, oil discharged from the oil tank 3Δ by the pump 5 via the foot valve 10 flows through the pipe 4 through the check valve 9, and is further returned to the oil tank 3B via the cutoff valve 8 on the end side of the pipe 4. In this state where oil flows in the pipe 4 in a regular manner and at an appropriate speed, the timer 7 is intermittently turned on.
The shutoff valve 8 is set to be off, and the shutoff valve 8 is intermittently opened and closed at a rapid rate.

When the shutoff valve 8 is rapidly closed, the flow of oil is stopped at the moment it is opened, and its kinetic energy changes into high-pressure compression work, increasing the density of oil, which is a compressible fluid. The surge pressure suddenly rises, and the surge pressure is l1i
Piping 4 with oil as a transmission medium as s-waves or pressure waves
The wave propagates inside the wave, violently collides with the check valve 9 on the other end side, becomes a reflected wave, and travels in the opposite direction. During this propagation, the shock wave forms a water hammer effect, that is, a surging effect, which hits the entire oil-filled wall inside the pipe 4 rapidly and violently. This surging effect weakens with time, but the cutoff valve 8 is intermittently opened and closed at a shorter period than the surging effect becomes smaller and is additively superimposed with the reflected wave, so the surging effect becomes large. is repeatedly applied to the inner wall surface of the pipe 4.

By intermittently applying shock waves due to the above-mentioned surging action to the inner wall surface of the pipe 4, foreign matter lurking on the inner wall surface of the pipe 4 or in the recess can be removed, and even latent foreign matter can be peeled off from the inner wall surface.

In this way, latent foreign substances are peeled off from the inner wall surface of the pipe 4 and mixed in the pipe, so the above-mentioned shutoff valve 8, which has been opened and closed intermittently, is kept open. pump 5
The oil is returned to the oil tank 3B by using a thin filter or strainer attached to the outlet of the hose 6, etc.
It is possible to easily capture and remove foreign objects mixed in the music.

According to this cleaning method, cleaning inside the pipe 4 can be completed in an extremely short time, and the inner wall of the pipe 4 after cleaning can be sufficiently cleaned.

The specific effects of the present invention will be described below using experimental examples shown in Figure M2 and below.In the experimental example shown in Figure 2, a device for measuring actual values was installed in It is attached.

That is, the oil pressure discharged by the pump 5 can be adjusted by a gate valve 11 adjacent to the check valve 9, and the discharge pressure is measured by a pressure gauge 12.

A gate valve 13 is installed in the middle of the pipe 4 to guide oil in the pipe 4 to a pressure oscillator 14, and a recorder converts the frequency of the pressure oscillator 14, whose oscillation frequency changes depending on the pressure, into voltage and records it. At 15, it is possible to record the oil pressure during operation of the casing, and at the same time, at a pressure gauge 17 with a gate valve 16 interposed, it is possible to directly use the oil pressure in a steady flow.

Further, a flow meter (not shown) is attached to the outlet of the bore 6 so that the flow rate of oil in the pipe 4 can be measured.

In the experimental example, the pipe 4 laid as shown in FIG. 3 was used.

That is, the piping 4 is constructed by connecting pipes of 32A skedicole 80 with a joint, and is laid in the form of two parallel rails with rising parts 19 and 19 in the middle, and the sampling piece 20 is interposed at the tip of the pipe 4. A folding piping route A is formed, and the end of one piping 4, which will be the discharge side, is connected with the hose 2 to a pump unit 21 in which the pump 5 and the oils 13A and 3B are integrated, and the other end, which will be the return side. A shutoff valve 8 is connected to the end of the pipe 4 . The pump unit 21 has a discharge amount of 350 n,' minutes, and has an oil tank (
3Δ, 3B integrated) is 50i.

Gate valves 22.22 are interposed approximately in the middle of the portion of the pipe 4 laid in the shape of two parallel rails, and the pipe route is turned back at the gate valve 23 in front of these gate valves 22.22. It is now possible to switch to B.

The above route A is 74.155m, and route B is 34.77m.
It is 5m.

The sampling piece 20 or 24 is for checking the removal effect of foreign matter in the recess, and as shown in FIG. A step-like recess 25 is formed in the middle of the hollow part, and a foreign object 26 such as metal powder is stored in each recess 25, and a foreign substance 26 such as a metal powder is stored in the recess 25. The lid 27 that closes the hole formed in the wall surface can be opened to store the foreign matter 26 or to check the degree of removal after cleaning.

In the pipe 4 laid as described above, 5 is Ω/c
Operating the tire 7 at a steady flow pressure of +++',
Even if the on/off pulse period of the timer 7 is changed, the impact pressure when the shutoff valve 8 is rapidly opened and closed remains about the same as shown in (a >, <b >, and (c)) in Fig. It reaches 70 k (1/Cm') and hits the inner wall surface of the pipe 4 in a short period in an impulse manner, and this blow is applied to the entire area of the inner wall of the pipe 4.

In FIG. 5, for example, the opening/opening pulse of 3 seconds/1 second means that the timer 7 is turned on for 3 seconds to close the cutoff valve 8, and then turned off for 1 second to open the cutoff valve 8. .

In addition, the measured values in Figure 5 are the same when the discharge flow rate is 3501/min, 2 circuit lengths are 75 m, the recording paper feed speed is 2.5 ca+/sec, and the opening/closing pulse is changed. Indicates pressure.

Even when the period of the opening/opening pulse mentioned above is changed, the piping 4
Foreign matter 26 (immediately removed) was housed in each recess 25 in the sampling piece 20.

In order to produce the surging phenomenon required for cleaning in the present invention, the flow rate of oil in the pipe 4 is at least 3 Ill.
/second or more is desirable, and a pump that can withstand oil pressure at this flow rate is required, but a high-pressure pump as in the conventional example is not required.

In addition, unlike conventional high-pressure pumps, the high-pressure pump does not have to operate at high pressure for a long period of time, but only needs to act in an impulse-like manner for a short period of time, so it can be used for piping with low pumping pressure (in other words, the instantaneous Alternatively, it can be used if the pressure is lower than the maximum pumping pressure for a short period of time.)

Although two oil tanks are used in FIG. 1, it is clear that one oil tank can be used in common.

In the first embodiment, the oil in the oil tank 3A is pumped to the pump 5.
At ii! It is directly discharged or sent out to the pipe 4 side, but the pump is used to connect the pipe 4! The oil can be poured into a container higher than the installed position, or the oil tank 3A can be set at the top using a hoist or other equipment, or by hand, and the oil can be discharged or sent to the piping 4 side using the potential energy. It can also be formed.

In addition, in the first embodiment, the check valve 9 is used, but
When using the above potential energy, check valve 9 can prevent backflow! ! The stop valve 9 is not necessarily required when the shock wave generated by the cutoff valve 8 alone is sufficient without forming a reflected wave against the shock wave.

Although the blocking piece 8 is a solenoid valve controlled by a timer 7, it can also be operated by manually controlling the current flowing through the solenoid of the solenoid valve, not limited to the timer 7. or,
The valve is not limited to a solenoid valve, but may be any other type of valve as long as it can be opened and closed rapidly.

In the above embodiment, the cutoff valve 8 and the like are connected to the tin of the piping 4;
The 4n type is formed on the side of the pipe so that the entire area of the pipe 4 can be cleaned, but if it is desired to limit the part to be cleaned, the above-mentioned cleaning device 1 etc. can be installed on both sides of the part. It is clear that the cleaning method described above can be used.

It should be noted that the present invention can be used not only with oil but also with water, and can also be made to function in substantially the same way using other liquids.

Furthermore, when a low-cost liquid such as water is used, foreign matter mixed in the fluid can be thrown out by shock waves and discharged together with the fluid into a drainage tank or the like.

It is desirable that the shutoff valve 8 is capable of not only opening but also opening at a rapid rate, but depending on the situation, it may function satisfactorily if only opening is done at a rapid rate.

Also, if you repeatedly apply %1, the positive effect will be greater, but for foreign matter that is easy to clean, it is sufficient to manually open and close the shutoff valve 8 several times. In some cases, cargo that is easily damaged can be sufficiently removed by simply applying damage waves in a single light, and the present invention is not limited to the case in which ν waves are repeatedly applied.

[Effect of the invention 1 J: Sea urchin described above] According to the present invention, foreign matter inside the pipe is removed by striking the wall inside the pipe with a shock wave generated by rapidly closing the shutoff valve. Therefore, the foreign matter that has become visible on the wall surface or the foreign matter that is in the recess can be knocked out into the installation 4 in a short time, even latent foreign matter, and cleaning can be completed in a short time.

Therefore, it is possible to significantly reduce the cost of staffing and electricity costs.

Further, it does not require a high-pressure pump like the conventional example, and can be realized with a simple configuration and at low cost. In addition, it is for rust prevention and cannot be completely removed by conventional flushing cleaning methods.
It is also possible to eliminate parts of the film that are likely to peel off but have the potential to become latent foreign substances that cannot be easily removed, and it is possible to significantly prevent damage to the tow in which the control system using hydraulic pressure or the like is actually activated.

[Brief explanation of drawings]

1 to 5 relate to one embodiment of the present invention, FIG. 1 is an explanatory diagram showing the configuration of a cleaning device of one embodiment, and FIG. 2 is an explanatory diagram showing a cleaning device equipped with a measuring device; Figure 3 is a schematic perspective view without showing the installed piping in the experimental example, Figure 4 is a partially cutaway side view showing the sampling piece provided in Figure 3, and Figure 5 is a diagram using the piping in Figure 3. FIG. 3 is a waveform diagram showing a pressure waveform of a shock wave when 1...Cleaning device 2, 6...Hose 3A, 3B...
・Oil tank 4 river piping 5...Pump 7...Timer 8...Jbu Arai 9...Check valve 10...Foot valve 11, 13.16...Gate valve 12.17... Pressure gauge 14...pressure! Shaker 15...Recorder 20.2
'l...Sampling piece 21...Pump unit 25...Recess 26...Foreign object Figure 1 Figure 2 Figure 3 Distortion Figure 4

Claims (7)

[Claims] (1) By rapidly shutting off the liquid being discharged or sent out from one end of the pipe containing the piping of the part desired to be cleaned, using a shutoff valve installed at the other end, A method for cleaning the inside of a pipe using shock waves, characterized in that the inside of the pipe is cleaned by hitting the inside with a shock wave. (2) A discharge means for discharging or delivering liquid from one end side including the piping of the part desired to be cleaned, and a discharge means attached to the other end side, capable of at least rapid opening, and capable of discharging liquid by said opening. It is characterized by comprising a shutoff valve that allows the generation of shock waves! %7 Cleaning of the inside of piping using shock waves @ installation. (3) The apparatus for cleaning the inside of piping using shock waves according to claim 2, wherein the liquid is oil, water, or another liquid. (4) The method for cleaning the inside of a pipe using shock waves according to claim 2, wherein the discharge means is formed using a pump. (5) Claim 2, characterized in that the discharge means is formed using a fluid tank located at a higher location than the piping.
1f6 device for cleaning the inside of piping using shock waves as described in Section 1. (6) The apparatus for cleaning the inside of piping using shock waves according to claim 2, wherein the discharge means is equipped with a valve for preventing backflow of liquid. (7) The apparatus for cleaning the inside of piping using shock waves according to claim 2, wherein the cutoff valve is a solenoid valve.