JPH0567386B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in an abrasive jet method for cutting rocks, concrete, etc.

[Conventional technology]

Traditionally, a method has been used to cut rocks and concrete by injecting a high-pressure water jet from a nozzle.

In order to improve the machinability of this high-pressure water jet, a so-called abrasive jet construction method is carried out in which abrasive (abrasive material) is mixed into the high-pressure water jet.The jet injection device used in this method is A nozzle having a structure in which a mixing chamber is provided in the nozzle body, an abrasive supply path and a high-pressure water supply nozzle communicating with the mixing chamber are provided, and a discharge nozzle is further arranged on the axis of this nozzle via the mixing chamber. is widely used.

[Problem to be solved by the invention]

However, in the conventional abrasive jet construction method, as a means of mixing the abrasive into the high-pressure water jet, a fluid such as air or water is used to feed the abrasive to the high-pressure water jet nozzle, so the supply of this fluid must be stopped. In this case, the abrasive mixed in the fluid may settle in the transport pipe forming the abrasive supply path and block the transport pipe. Therefore, each time the supply of fluid to the transport pipe is stopped, the transport Since the fluid in the tube must be removed, abrasive loss increases.

Furthermore, the abrasive is supplied in a pulsating manner and is uneven in quantity, making it impossible to cut smoothly.

Also, in the mixing chamber of the nozzle body where the high-pressure water jet and abrasive are mixed, if the supply of the abrasive mixed fluid is stopped, the abrasive will settle in the mixing chamber, and the settled abrasive will flow into the inlet of the jet's discharge nozzle. There is a problem that the engine becomes clogged and the engine does not operate smoothly when starting the jet.

Therefore, even after cutting is finished, it is necessary to flush the abrasive by pumping fresh water into the abrasive supply pump until all the abrasive accumulated in the abrasive supply pump, pipes, and mixing chamber is removed. This will reduce efficiency.

Additionally, the larger the particle size of the abrasive, the greater the cutting ability of the high-pressure water jet, but when using abrasive with a large particle size, conventional pumps suffer from severe wear and tear and become unusable. In the feeding of abrasives, there is a problem in that these fluids pulsate and the abrasives flow freely within the fluids, resulting in uneven mixing, making it impossible to supply a constant quantity.

The present invention provides an abrasive jet construction method aimed at solving these problems.

[Means to solve the problem]

In order to achieve the above object, the abrasive jet method of the present invention sprays a high-pressure water jet onto the workpiece from a nozzle while mixing the abrasive with a high-pressure water jet. The method is characterized in that it is mixed with a high viscosity fluid in the form of a grease or gel such as a polymer viscosity agent, and then this high viscosity fluid is supplied to a high pressure water jet.

As the abrasive supply means, it is preferable to use a squeeze pump having two squeeze hoses in which the rotational phases of the squeeze rollers are shifted.

[Effect]

When an abrasive is mixed into a grease-like or gel-like high-viscosity fluid such as bentonite or a polymer-based viscous agent, the abrasive becomes encapsulated in a certain area by the fluid, and the abrasive has a large particle size. Even if the material is dispersed uniformly throughout the fluid, it is supplied at a constant rate to a high-pressure water jet, and is sprayed onto the workpiece by the high-pressure water jet to deeply penetrate the workpiece. And it cuts efficiently.

Furthermore, even after the cutting operation is finished, there is almost no risk of abrasive settling in the abrasive-contaminated animal supply channel, and the jet discharge nozzle will not be clogged due to abrasive settling in the mixing chamber, so when starting the next jet operation is performed smoothly.

In addition, if a squeeze pump having two squeeze hoses with squeeze rollers with rotational phases shifted from each other is used as the abrasive supply means, pulsation can be eliminated and smooth quantitative feeding of the abrasive-containing fluid becomes possible. .

〔Example〕

An embodiment of the present invention will be explained with reference to the drawings. Fig. 1 shows a jet injection device suitable for carrying out the method of the present invention. A mixing chamber 2 is provided at the bottom, and a discharge nozzle 3 whose upper end inlet opens at the center of the bottom of the mixing chamber 2 is provided. A cylindrical guide hole 4 whose opening is at the center of the upper surface of the mixing chamber 2 is provided.

Reference numeral 5 denotes a high-pressure water supply pipe that penetrates one side of the nozzle body 1 and has its tip disposed within the guide hole 4, and has a high-pressure water pipe at its tip, with its open end facing the inlet of the discharge nozzle 3. A water jet nozzle 6 is attached.

Reference numeral 7 denotes an abrasive supply pipe that communicates with the mixing chamber 2 from one side of the nozzle body 1.

Reference numeral 8 denotes a cylindrical shutter disposed in the guide hole 4 so as to be slidable up and down, and by bringing the lower end of the opening into contact with the periphery of the inlet of the discharge nozzle 3, the mixing chamber 2 is connected to the high-pressure water jet nozzle 6 side. The supply pipe 7 side forming the abrasive supply path can be shut off. This shutter 8 is moved up and down by screwing a screw rod 9 fixed onto its upper surface into a nut 10 rotatably disposed on the upper surface of the nozzle body 1, and rotating the nut 10. It is.

Reference numeral 11 denotes a long hole formed in the longitudinal direction of one side of the shutter 8 through which the high-pressure water pipe 5 is inserted, and the high-pressure water pipe 5 prevents the shutter 7 from rotating. It is something that is present.

Reference numeral 12 denotes an abrasive supply mechanism, in which a motor 16 rotates a common shaft 15 of two parallel squeeze pumps 13 and 14, and the respective squeeze pumps 13 and 14 are fixed to the shaft 15.
The rotational phases of the squeeze rollers 17, 17, 18, 18 are shifted in the right angle direction, and the squeeze hoses 1 of these squeeze pumps 13, 14 are
The discharge sides of the pumps 9 and 20 are connected to the supply pipe 7, and the suction sides thereof are connected to the abrasive mixed fluid storage tank 21.

22 is the nozzle body 1 from the upper end of the other side of the mixing chamber 2.
This is a ventilation/overflow hole that communicates with the outside on the other side.

Now, a fluid 24 containing a large number of abrasives 23 such as silica sand, garnet, or iron powder with a particle diameter of about 1 mm is stored in a storage tank 21.

As this fluid 24, a grease-like or gel-like substance having a high viscosity such as bentonite or a polymer-based viscous material is used, and the abrasive 23 is mixed uniformly throughout the fluid 24. If mixed, the abrasive 23
are held in a uniformly dispersed state without settling in the fluid 24.

When such an abrasive-containing fluid 24 is stored in the storage tank 21 and the motor 16 of the abrasive supply mechanism 12 is started, the squeeze rollers 17 and 18 of the squeeze pumps 13 and 14 rotate and the fluid 24 mixed with the abrasive is stored in the storage tank 21. The fluid 24 is forced into the supply pipe 7 through the squeeze hoses 19 and 20.

At this time, since the squeeze pumps 13 and 14 are arranged in two series and the rotational phases of the rollers 17 and 18 of these squeeze pumps 13 and 14 are shifted, the abrasive mixed fluid 24 is caused to pulsate in the supply pipe 7. It can be supplied quantitatively and continuously without any problems.

The fluid 24 fed into the mixing chamber 2 of the nozzle body 1 from the supply pipe 7 is shredded by the high-pressure water jet 25 jetted from the jet nozzle 6 by force-feeding high-pressure water to the water pipe 5. The water is mixed with the high-pressure water jet 25 and sprayed from the discharge nozzle 3 as an abrasive jet 26 onto a workpiece such as rock or concrete at a spray pressure of 1000 to 2000 kg/cm ² to cut the workpiece. It is something.

When the cutting is completed, the nut 10 is rotated to move the shutter 8 downward so that its lower end comes into contact with the vicinity of the inlet of the discharge nozzle 3 to cut off the fluid supply pipe 7 and the discharge nozzle 3, and the shutter 8 is moved downward. After the fluid 24 inside is discharged from the discharge nozzle 3 by the high pressure water jet 25, the supply of the high pressure water and the fluid 24 mixed with abrasive is stopped.

While the fluid 24 in the shutter 8 is being discharged, the abrasive-containing fluid 24 is supplied to the mixing chamber 2 outside the shutter 8, but the filled fluid 24 is discharged to the outside from the ventilation/overflow hole 22.

Next, when performing cutting work, high-pressure water is jetted from the high-pressure water jet nozzle 6 through the discharge nozzle 3 through the shutter 8, and then the shutter 8 is opened to send the abrasive-containing fluid 24 to the mixing chamber 2. It is something that is supplied internally.

If a pressure control valve is attached to the ventilation/overflow hole 22, the abrasive mixed fluid 24 in the mixing chamber 2 can be brought into a constant pressure state, and by detecting this pressure, the squeeze pump 13 , 14 can be controlled.

Further, in the above embodiment, a jet injection device having a shutter 8 disposed inside the mixing chamber 2 is used, but a jet injection device having no such shutter is used.
The present invention can also be practiced using a conventional jet injection device as shown in the figure.

〔Effect of the invention〕

As described above, according to the abrasive jet method of the present invention, in the abrasive jet method in which the high-pressure water jet is sprayed from a nozzle onto the workpiece while mixing the abrasive with the high-pressure water jet, the abrasive is mixed with a polymer-based viscous agent, etc. The abrasive is mixed with a grease-like or gel-like high-viscosity fluid, and then this high-viscosity fluid is supplied to a high-pressure water jet. Even if the abrasive has a large particle size, it hardly settles and can be supplied to a high-pressure water jet while being uniformly dispersed throughout the fluid. Even after the work is completed, there is almost no risk of abrasive settling in the abrasive-containing fluid supply channel, and the jet discharge nozzle is no longer clogged due to settling of abrasive in the mixing chamber, making it easy to operate when starting the next jet. can be carried out smoothly and work efficiency can be improved.

Furthermore, since the abrasive is evenly mixed and supplied to the abrasive-containing fluid, pulsating supply is eliminated, and stable cutting is possible.

In addition, by adopting a squeeze pump with two squeeze hoses with squeeze rollers out of rotational phase as the abrasive supply means, pulsation can be eliminated and the abrasive-containing fluid can be fed in a smoother fixed quantity. and, in addition,
Even if a large-diameter abrasive is used, the squeeze pump hardly wears out, so it can cut objects such as rocks and concrete deeply and efficiently.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, and FIG. 1 is a partially vertical schematic front view of a jet injection device used in the method of the present invention, FIG. 2 is a simplified cross-sectional view of a squeeze pump, and FIG. FIG. 3 is a longitudinal sectional view of the jet injection device. DESCRIPTION OF SYMBOLS 1... Nozzle body, 2... Mixing chamber, 3... Discharge nozzle, 5... High pressure water supply pipe, 6... High pressure water jet nozzle, 7... Abrasive supply pipe, 8
... Shutter, 12 ... Abrasive supply mechanism,
13,14...Squeeze pump, 17,18...
Squeeze roller, 19, 20... Squeeze hose, 23... Abrasive, 24... High viscosity fluid.

Claims (1)

[Claims] 1 In the abrasive jet method, in which a high-pressure water jet is sprayed onto the workpiece from a nozzle while mixing the abrasive with a high-pressure water jet, the abrasive is mixed with a grease-like or gel-like high-glue agent such as a polymer-based viscous agent that prevents the abrasive from settling. An abrasive jet construction method characterized by mixing the high viscosity fluid with a high-viscosity fluid and then supplying the high-viscosity fluid to a high-pressure water jet.