JPH0319033B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) This invention relates to an abrasive water jet cutting device.

(Prior Art) A conventional abrasive water jet cutting method will be explained based on FIG. Conventionally, in cutting using an abrasive water jet, as shown in the figure, ultra-high pressure water 53 is supplied from an ultra-high pressure water pump 51 to a jet nozzle (abrasive nozzle) 52, while ultra-high pressure water 53 is supplied from an abrasive tank 54 to the jet nozzle 52. A dry abrasive 55 is supplied, and the dry abrasive 55 is mixed with the ultra-high pressure water 53 in the mixing chamber 56 in the jet nozzle 52, and the ultra-high pressure water 57 containing the dry abrasive is applied to the material to be cut. It was done by spraying. As the dry abrasive material 55, for example, silica sand, cast iron grid, garnet, alumina, etc. with an average particle diameter of about 0.2 to 0.8 mm have been used.

(Problems to be Solved by the Invention) The conventional abrasive water jet cutting method described above has the following drawbacks. First of all, since the dry abrasive material 55 is used, the abrasive nozzle tip 57 wears out prematurely, resulting in a very short service life. Secondly, since the dry abrasive material 55 has a large particle size, the cutting width (kerf width) becomes wider than the abrasive nozzle tip diameter, and burrs are formed on the back surface of the material to be cut. be done, etc.
The disadvantage is that precise cutting cannot be performed.

For this reason, the present inventors filed an earlier application (Japanese Patent Application No. 1983-
No. 36072), we proposed a method of supplying a suspension containing fine abrasives to an ultrahigh-pressure water jet for cutting, and attempted to eliminate the above-mentioned drawbacks.

This invention has been made in order to provide an abrasive water jet cutting device that is most suitable for carrying out the method proposed above, and its purpose is to collect and reuse abrasive material. An object of the present invention is to provide an abrasive water jet cutting device capable of cutting.

(Means for Solving the Problems) Therefore, the abrasive water jet cutting device of the present invention includes a nozzle for spouting water jet mixed with an abrasive, a catcher for collecting the spouted abrasive, and a catcher for collecting the spouted abrasive. It has a circulation path for returning the abrasive material from the catcher to the nozzle, and a settling tank and a concentration control tank are interposed in the circulation path in order from the catcher side, and
Both of the tanks communicate with each other via a communication path near the bottom of the settling tank, and further, a system for sending the precipitated abrasive from the settling tank to the concentration control tank via the communication path. The configuration includes a sending means.

(Function) In the abrasive water jet cutting device described above, when water jet mixed with an abrasive is injected from the nozzle in order to cut the material to be cut, the water jet cuts the material to be cut, and then the water jet cuts the material to be cut. The waste is collected and guided to a settling tank. The abrasive material is then precipitated in the settling tank, and the abrasive material settled at the bottom of the settling tank is guided by the delivery means to the concentration control tank via the communication path. In the concentration control tank, the concentration of the abrasive is adjusted as appropriate, and the suspension after the concentration adjustment is supplied to the nozzle again via the circulation path.

(Embodiments) Next, specific embodiments of the abrasive water jet cutting device of the present invention will be described in detail with reference to the drawings.

In FIG. 1, 1 is an abrasive water jet cutting device, 2 is its jet nozzle, and a high-pressure water supply hose 3 for supplying ultra-high pressure water is connected to the base end of this jet nozzle 2. At the same time, a suspension supply hose 4 for supplying a suspension containing fine abrasive particles is connected to one side. In front of the jet nozzle 2 in the jetting direction (in the case of the figure, below the jet nozzle 2),
A catcher 6 is disposed to collect the abrasive used for cutting the material 5 to be cut, and a circulation path 7 is provided between the catcher 6 and the jet nozzle 2.
is formed. This circulation path 7 is for returning the fine abrasive material collected by the catcher 6 to the jet nozzle 2, and along the way there are a settling tank 10 in order from the catcher 6 side,
A concentration control tank 11 and a stirring tank 12 are respectively provided. In this case, the bottom of the peripheral wall of the catcher 6 and the top of one side wall of the settling tank 10 are connected to the recovery pipe 13.
The other side wall bottom of the precipitation tank 10 and the one side wall bottom of the concentration control tank 11 are connected via a communication pipe 14. Then, the other side wall near the bottom of the concentration control tank 11 and the stirring tank 12
The bottom part of one side wall is connected to the bottom part of the side wall through the connecting pipe 19.
Further, the intermediate portion of the other side wall of the stirring tank 12 and one side portion of the jet nozzle 2 are connected via the suspension supply hose 4, respectively. In addition, the above recovery pipe 1
3 is provided with a first slurry pump 15, and the connecting pipe 19 is provided with a second slurry pump 16.
is interposed. Inside the settling tank 10,
Alternately insert baffle plates 1 from the top plate side and the bottom plate side.
7 and 18 are arranged in an extended manner, and a screw pump 20 for delivering the precipitated fine abrasive material to the concentration control tank 11 through the communication pipe 14 is arranged at the bottom. This screw pump 2
0 passes through the baffle plate 18 extending from the bottom plate side. Further, a drain pipe 21 for discharging supernatant water to the outside is connected to the upper part of the other side wall of the settling tank 10. Inside the concentration control tank 11, a propeller of a stirring tank 22 is inserted, and a hydrometer 23 for measuring the specific gravity of the suspension mixed with fine grain abrasive sent out from the settling tank 10 is arranged. has been done. Further, a first water supply pipe 24 is connected to the upper part of the other side wall, and the above-mentioned hydrometer 2 is connected to this first water supply pipe 24.
Solenoid valve 25 whose opening degree is controlled by the signal from 3
is interposed. Inside the stirring tank 12,
A propeller of an agitator 26 is inserted, and a fine abrasive supply hopper 27 is attached to the upper part, and a second water supply pipe 30 is connected. A water supply valve 31 is interposed in this second water supply pipe 30. As the fine abrasive material, for example, alumina-based fine powder or silicon carbide-based fine powder with an average particle size of 100 μm or less is used. Further, the concentration of the suspension is adjusted to, for example, 20 to 70%.

Next, the case where the material to be cut 5 is cut using the abrasive water jet cutting device 1 will be described. In this case, first, as shown in the figure, the workpiece 5 is placed between the jet nozzle 2 and the catcher 6.
Next, ultra-high pressure water is supplied to the jet nozzle 2 through the high-pressure water supply hose 3, and a suspension containing fine abrasive is supplied to the jet nozzle 2 through the suspension supply hose 4. Then, a water jet mixed with fine abrasive particles is jetted from the jet nozzle 2, and the material to be cut 5 is thereby cut. Next, the water jet is received by the catcher 6, and the fine abrasive material is recovered.
is driven and pumped into the sedimentation tank 10. Sedimentation tank 10
The collected waste liquid pumped into the tank naturally settles while meandering between the baffle plates 17 and 18, and the fine abrasive particles with a particle size suitable for reuse collect at the bottom of the tank, and the small particle size that is not suitable for reuse accumulates at the bottom of the tank. The suspended fine abrasive particles (for example, 3 μm or less in the case of alumina) are discharged to the outside through the drain pipe 21 together with the supernatant water. Next, the fine abrasive material settled at the bottom of the settling tank 10 is pumped by the screw pump 20 to the concentration control tank 11 through the communication pipe 14. Then, the pumped fine abrasive will be mixed into the suspension in the concentration control tank 11, and the specific gravity of the suspension containing the fine abrasive will be measured by the hydrometer 23, and the concentration will be measured by the hydrometer 23. Control will be performed automatically. That is, if the specific gravity of the suspension exceeds the set value, the solenoid valve 25 is opened in response to a signal from the hydrometer 23 to supply water, and if the specific gravity does not reach the set value, water is supplied. Instead, only the suspension containing fine abrasive material is received from the settling tank 10. Note that the stirring tank 22 is operated as appropriate to maintain a uniform concentration. Next, the suspension whose concentration has been adjusted in the concentration control tank 11 is pumped to the stirring tank 12 by driving the second slurry pump 16 . and stirring tank 1
In step 2, the agitator 26 is operated to stir the suspension, and at the same time, the fine abrasive and water are supplied, but in this case, since the concentration of the suspension has already been adjusted, Just do it in small amounts. Then, the suspension in the stirring tank 12 is again supplied to the jet nozzle 2 to reuse the abrasive.

In the above embodiment, the communication pipe 14 is used as a communication path that communicates the precipitation tank 10 and the concentration control tank 11.
We have taken as an example the case where a sedimentation tank 1 is installed.
0 and the concentration control tank 11 may be arranged with one wall separating them, and in that case, a through hole may be bored in the wall as a communication path. Also, concentration control tank 1
1 and the stirring tank 12 may be integrated.

In the abrasive water jet cutting device of the above embodiment, since the natural settling method is adopted in the settling tank 10, the entire device can be manufactured at a lower cost than when a forced settling method is adopted. Furthermore, since the abrasive material used hardly changes in particle size, shape, etc., no problem arises when it comes to recycling.

(Effects of the Invention) In the abrasive water jet cutting device of the present invention, a settling tank and a concentration control tank are interposed in the circulation path for returning the abrasive material from the catcher to the nozzle. Since the precipitated abrasive is sent to the concentration control tank by the sending means through a communication path near the bottom of the settling tank, the abrasive used to cut the material to be cut can be recovered and reused. can do. Therefore, unlike waterjet cutting using a dry abrasive, there is no need for post-treatment of the abrasive, and costs for purchasing the abrasive and post-processing can be reduced.

[Brief explanation of the drawing]

FIG. 1 is an overall structural diagram showing one embodiment of the abrasive water jet cutting device of the present invention, and FIG.
The figure is an explanatory diagram of a conventional abrasive water jet cutting method. DESCRIPTION OF SYMBOLS 1... Abrasive water jet cutting device, 2... Jet nozzle, 6... Catcher, 7... Circulation path, 10... Sedimentation tank, 11... Concentration control tank, 14... Communication pipe, 20... Screw Pump.

Claims (1)

[Claims] 1. Abrasive water jet cutting having a nozzle for ejecting a water jet mixed with abrasive, a catch for collecting the ejected abrasive, and a circulation path for returning the abrasive from the catch to the nozzle. In the apparatus, a settling tank and a concentration control tank are interposed in the circulation path in order from the catcher side, and both tanks communicate with each other via a communication path at a position near the bottom of the settling tank. An abrasive water jet cutting device, further comprising a delivery means for delivering the precipitated abrasive from the settling tank to the concentration control tank via the communication path.