JPH0336395B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is an abrasive jet that cuts a workpiece by spraying granular material such as sand together with a high-pressure water jet onto a workpiece such as a concrete structure or rock mass. related to a cutting device.

[Prior Art] This cutting method using an abrasive jet is well known and is used to cut various objects. The cut surface is especially clean and any cut surface can be formed by moving the jet nozzle, so other cutting techniques such as flame jet or burning bar method, which burns a mixture of iron and aluminum by supplying oxygen, can be used. It is preferable compared to etc.

However, since particulate matter and water are used, the particulate matter and water are scattered at the cutting site. Normally, a cutting site is a place where there is no problem even if particles and water are scattered like this, but the particles and water are a waste.

The granular material used in this abrasive jet cutting device is usually sand with a diameter of 2 mm or less, and sand with a diameter of 0.5 mm or less has low kinetic energy, resulting in poor cutting efficiency;
The above methods are unsuitable because the nozzle is subject to wear and tear.

This makes it relatively difficult to prepare granules of appropriate size.

For this purpose, the technology described in Japanese Patent Application Laid-Open No. 60-226970 has been proposed, but since solids that cannot be used in abrasive jets are processed using a solidifying agent, the equipment becomes complicated. , water reuse also requires a large number of tanks.

[Problems to be Solved] Therefore, an object of the present invention is to provide a cutting device using an abrasive jet that has a relatively simple structure and can supply reusable solids and water to an abrasive jet nozzle. There is something to do.

[Means for Solving the Problems] According to the present invention, in a cutting device using an abrasive jet that cuts a workpiece by spraying granular materials together with a high-pressure water jet onto the workpiece from a jet nozzle, a collection device is provided below the jet nozzle. a first feeding device for sending the slurry collected in the recovery device to the mechanical separation device, and a jet nozzle for sending the reusable granules and new granules separated by the mechanical separation device. a second feeding device for sending water to the water, a sedimentation tank for storing water and granular materials and cutting particles that are the most unusable solids separated by the first separation device, and a stirring device provided in the sedimentation tank. , a purified water line that sends water from the settling tank to the high-pressure pump of the jet nozzle, a pump that sends clean water to the high-pressure pump, a discharge line that discharges solids from the settling tank, and a dewatering device installed in the discharge line. We are prepared.

[Description of the effects of the invention] Therefore, the granular material cut by the abrasive jet nozzle, the cut particles (solid content thereof), and water are recovered by the recovery device, and the water and solid content are recovered by the recovery device. That is, the slurry is delivered to the mechanical separator by the first delivery device. The recyclable solids are then fed to the jet nozzle together with new granules. Solids that cannot be reused enter a settling tank, where they are stirred by a stirring device and settled, after which they are discharged from a drainage line, dehydrated by a dewatering device, and disposed of.

The water above the sedimentation tank is sent to a high-pressure pump for reuse, and is then injected from a jet nozzle together with fresh water.

In this way, the mechanical separator can easily separate recyclable particles with relatively large particle sizes from those with small particle sizes. Note that during the cutting operation, the diameter of the granules becomes smaller due to wear. Additionally, the diameter of the particles to be cut is generally small. Therefore, when separating the slurry, it is only necessary to separate the slurry having a large diameter.

Since a settling tank stirred by a stirring device is used, even if very small particles are supplied to the abrasive jet nozzle together with water, the cutting operation is not affected, and the solids to be discharged can be settled. Since the discharged solid content is dehydrated, it is easy to dispose of. In this way, most of the water recovered by the recovery device for jet water can be reused, and there is no waste.

As a result, substantially only the particles to be cut can be recovered.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows an apparatus implementing the present invention,
A concrete structure C, which is an object to be cut, is shown being cut by an abrasive jet J using a jet nozzle 1. This jet nozzle 1 is supplied with high pressure water (pressure 2000~
2500Kg/cm ² ) is supplied, and the abrasive line 10
From 3 and 3, granules are sent in the manner described below. A recovery device 4 is provided below the jet nozzle 1, and is adapted to recover particulate matter and particles to be cut together with the water used for cutting. The slurry collected in this way is transferred to collection line 5.
is sent to a mechanical separating device 7 by a feeding device 6 provided at As this feeding device 6, any suitable means such as pneumatic transport using a slurry pump or compressor can be used. Mechanical separation device 7
For example, Utility Model Publication No. 53-35797 pertaining to the present applicant.
The vibrating screen described in the above publication can be used. The mesh of the screen used in this mechanical separator 7 is 1 to 0.5 mm, and reusable particulate matter is separated. This separated granulate is sent via line 8 and the new granulate stored in the granulate tank is sent via line 10 to the abrasive line 3 described above by means of a feed device, e.g. a slurry pump 11. Then, the abrasive jet J is ejected from the abrasive nozzle 1a provided in the jet nozzle 1 together with high-pressure water.

On the other hand, the slurry from which the reusable granules have been separated is sent to the settling tank 12. This sedimentation tank has a motor 1
A stirring blade 14 is provided, and the motor and the stirring blade constitute a stirring device. In this settling tank 12 and this second separator 12, the solid content S settles, and the upper water W passes through a filter F and is sent to a purified water line 16 by a pump 15. Further, fresh water is sent by a pump 17 from a fresh water supply source (not shown). The water sent by pumps 15 and 16 is pressurized by high pressure pump 2 and sent to jet nozzle 1.

The solid content S is discharged from a drainage line 18 by an appropriate device (not shown), dehydrated by a dehydrator 19, and disposed of.

FIG. 2 is a distribution diagram with the particle size D on the horizontal axis and the number of particles on the vertical axis. Curve A shows the distribution of particles before use, and curve B shows the distribution of particles in the object to be cut. Since the particle size of the particles is usually smaller than that of the granules, they can be easily separated using a screen or the like.

FIG. 3 shows the relationship between particle size and percentage in the first separation device 7, where curve X represents granules and curve Y represents particles. The particle size of the granular material becomes smaller due to the cutting operation. Particles having a large particle size can be used as granules in polishing materials. The solid content S settled in the settling tank 12 is discharged, and the upper water W
(contains very small solids that do not settle) are recycled.

[Summary] As described above, according to the present invention, the large diameter of the collected slurry is first separated and reused, and then the solid content is separated from the water and the water is reused, thereby reducing waste. It is also easy to treat the solid content.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an apparatus implementing the present invention;
FIG. 2 is a diagram showing the particle size distribution of the granular material and the particles of the material to be cut, and FIG. 3 is a diagram showing the ratio between the granular material and the particles of the material to be cut depending on the particle size. 1...Jet nozzle, 2...High pressure pump, 3
... Abrasive material line, 4 ... Recovery device, 5 ... Recovery line, 6 ... First feeding device, 7 ... Mechanical separation device, 11 ... Second feeding device, 12 ... Precipitation Tank, 13... Motor, 14... Stirring blade, 18...
Discharge line, 19...dehydration device.

Claims (1)

[Claims] 1. In an abrasive jet cutting device that cuts a workpiece by spraying particulate matter together with a high-pressure water jet from a jet nozzle onto the workpiece, a collection device is provided below the jet nozzle, and the slurry collected by the collection device is a first feeder for feeding the mechanical separator, a second feeder for feeding the recyclable granules and fresh granules separated by the mechanical separator to a jet nozzle; A sedimentation tank that collects water and granules and cutting particles that are the most unusable solids separated by the separation device, an agitation device installed in the sedimentation tank, and a high-pressure pump of the jet nozzle that transfers the water from the sedimentation tank. Cutting by an abrasive jet characterized by comprising a purified water line, a pump for sending clean water to the high-pressure pump, a discharge line for discharging solids from the sedimentation tank, and a dewatering device installed in the discharge line. Device.