JP2004330381A - Abrasive blasting method and blasting equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an abrasive blasting method which carries out abrasive blasting by ejecting an abrasive to a workpiece, and efficiently removes only impurity from mixed particles including the abrasive after the abrasive blasting and the impurity produced by the abrasive blasting, and also to provide blasting equipment. <P>SOLUTION: The abrasive blasting method comprises: an abrasive blasting step 1 of carrying out the abrasive blasting by ejecting the abrasive to the workpiece; a recovering step 2 of recovering the abrasive ejected to the workpiece and the impurity produced by the abrasive blasting, a dust removing step 3 of removing fine dust from the mixed particles recovered in the recovering step; a quantitative feeding step 4 of quantitatively feeding the mixed particles from which the fine dust is removed in the dust removing step; a screening step 6 of screening the mixed particles supplied from the quantitative feeding step, depending on dry specific gravity; and a reusing step of reusing the screened ejecting material screened in the screening step as the abrasive to be ejected to the workpiece. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

注）原料投入量に対し、分離された量の合計が減った分は、分離の際に集塵機に回収した分と、周囲に飛散した分の合計である。
【００３１】
試験例１では、ライト側では明らかにアルミナ粒子と思われる部分が分離・除去されていた。試験例２でも同様であり、ＭＧ粒子とアルミナ粒子の混合比４：１で分離されていた。さらに試験例３でも、試験例１と同様にアルミナ粒子が分離・除去されていた。試験例４では、試験例３のライト側について再度分離を行ったものである。試験例５では、試験例１の処理速度を約１．５倍としたものである。
【００３２】
次に、各試験例におけるライト側とヘビー側のＭＧ粒子とアルミナ粒子の混合率を下記の表２に示す。なお、表２中、比重は、新光電子（株）製比重測定器（電子はかり式比重計ＶＩＢＲＴ ＤＭＥ−２２０）にて測定した。
【００３３】
【表２】

【００３４】
表２に示す混合率から、試験例１〜３のライト側はいずれもアルミナ粒子の分離が良好に行われていることが分かる。特に、試験例１および２では５％以下まで分離されている。試験例４については、試験例３にて既にアルミナ粒子は相当量除去されていることから、ライト側もヘビー側も双方ともアルミナ粒子は殆ど存在していないことが分かる。試験例５からは、処理速度を上げると分離能が低下する傾向にあることが分かる。
【００３５】
【発明の効果】
以上説明してきたように、本発明によれば、被対象物に対し研削材を噴射してブラスト処理した後の研削材と、ブラスト処理により生じた不純物との混合粒子から、効率良く不純物のみを除去することができる。
【図面の簡単な説明】
【図１】本発明のブラスト処理の概要を示す工程図である。
【符号の説明】
１ ブラスト処理工程
２ 回収工程
３ 粉塵除去工程
４ 定量供給工程
５ 振動定量供給工程
６ 選別工程[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a blast processing method and a blast processing apparatus, and more specifically, efficiently mixes abrasives after blast processing by injecting abrasives to an object, and mixed particles of impurities generated by the blast processing. The present invention relates to a blast processing method and a blast processing apparatus capable of removing impurities. The blast treatment method and the blast treatment apparatus of the present invention include: mold cleaning, coating peeling, surface cleaning such as rust removal, concrete debris, deburring, removal of impurities and unnecessary substances caused by removal of etching debris of a substrate, and before coating. The present invention can be suitably applied to surface treatment of metals, plastics, woods, and the like, as well as patterning for glass crafts.
[0002]
[Prior art]
Blasting is used in almost all manufacturing industries such as automobiles, electrical equipment, construction, and chemicals, such as painting, kneading of raw materials, stirring, pressing, and injection molding. It has been used for applications such as cleaning and peeling, mold surface cleaning, deburring, scale removal, decorative arts crafts, and removal of mold materials during lost wax molding.
[0003]
A conventional blast processing apparatus used for such blast processing is composed of an injection device, a blast room, a collection and dust collection device for abrasives, and the like.
[0004]
[Problems to be solved by the invention]
The impurities separated or separated from the object by the injection of the abrasive in the blast room are conventionally separated partially by the wire mesh in the blast room, but the impurities close to the particle size of the abrasive (the mesh below the wire mesh) Was recovered along with the abrasive. Further, although fine dust is collected by a dust collector, other impurities are circulated in the path, and are eventually ejected together with the abrasive.
[0005]
In such a case, it is conceivable to separate impurities using a classifier having a high capacity.However, for example, if the level of dust collection is simply increased, even abrasives that can be reused originally will be separated. Inefficient. Therefore, it was practically impossible with the conventional classifier to effectively separate the abrasive from the impurities.
[0006]
As another method for collecting abrasives, a combination of a vibrating sieve and a classifier may be considered, but in this case, the separation efficiency is poor for forming a continuous circuit of the blasting process, which is not suitable for practical use. Was. It is also conceivable to take out the abrasive mixed with impurities from the continuous circuit of the blasting process and separate the impurities by a specific gravity separation method using a liquid or the like. I was unable to do so and it was unrealistic.
[0007]
Therefore, an object of the present invention is to provide a blast capable of efficiently removing only impurities from mixed particles of the abrasive after the abrasive is sprayed onto the object and subjected to the blast processing, and the impurities generated by the blast processing. An object of the present invention is to provide a processing method and a blast processing device.
[0008]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above-described problems, and as a result, have found that the above object can be achieved by adopting a dry specific gravity selection method under predetermined conditions for blasting, and to complete the present invention. Reached.
[0009]
That is, the blast processing method of the present invention, a blast processing step of performing blast processing by injecting an abrasive to the object,
A grinding step injected into the object, and a recovery step of recovering impurities generated by the blast processing,
A dust removal step of removing fine dust from the mixed particles collected in the collection step,
A quantitative supply step of quantitatively supplying the mixed particles from which fine dust has been removed by the dust removal step,
Sorting step of dry-type specific gravity sorting of the mixed particles supplied from the quantitative supply step,
A reuse step of reusing the blast material selected in the sorting step as an abrasive for the object,
It is characterized by including.
[0010]
In the blasting method of the present invention, dust generated in the sorting step can be suitably returned to the dust removing step. In addition, it is preferable that a vibration quantitative supply step is provided between the quantitative supply step and the sorting step, in which the mixed particles quantitatively supplied from the quantitative supply step are quantitatively supplied while applying fine vibration. Further, the abrasive is preferably plastic particles, and more preferably the particle size is 20 to 5000 μm.
[0011]
According to the blasting method of the present invention, even if the blasting abrasive has a particle diameter close to that of the blasting abrasive, when impurities having different specific gravities are mixed, the impurities can be efficiently removed. In particular, this is very effective when impurities are mixed in the abrasive and may adversely affect the blast target object such as roughening the surface of the target object.
[0012]
Further, the blast processing apparatus of the present invention includes a grinding material injection device for injecting abrasive, a blast room for performing blast processing with the injected abrasive, an abrasive collected from the blast room, and blasting. In a blast processing device having a separation device for separating impurities generated by the processing,
The separating device includes: a dust collector; a quantitative supply hopper for quantitatively supplying mixed particles of the abrasive and impurities from which fine dust has been removed by the dust collector; and a vibration to the mixed particles supplied from the quantitative supply hopper. It is characterized by comprising a vibrating feeder for supplying a fixed amount while feeding, and a dry-type specific gravity separator for selectively mixing the mixed particles supplied from the vibrating feeder.
[0013]
The blasting apparatus of the present invention does not require a separate means for selecting abrasives for reuse, so that it can be operated continuously. Therefore, the blast processing can be continuously and efficiently performed.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be specifically described with reference to the process chart shown in FIG.
In the blast processing step 1 shown in FIG. 1, a blast processing is performed by injecting an abrasive to an object.
[0015]
Various blasting devices such as a direct pressure type, a siphon type, a tumbler type, a barrel type, and a centrifugal type can be suitably used for the blasting. Note that these blasting processes are performed in a blast room in order to prevent scattering of abrasives and impurities generated by the blasting processes.
[0016]
The abrasive is not particularly limited as long as it can be separated from other substances having different specific gravities, for example, plastic materials, metals, alumina, wood, and the like, in a dry specific gravity sorting step described below in detail. Are plastic particles.
[0017]
The resin base material of such plastic particles is not particularly limited, but it is preferable to use a thermoplastic elastomer or a thermosetting resin. Examples of the thermoplastic elastomer include a nylon (PA) resin, a polycarbonate (PC) resin, an acrylonitrile butadiene styrene (ABS) resin, a polypropylene (PP) resin, a polyethylene terephthalate (PET), and a polyamide (PAE) resin. Olefin (TPO) resin, rubber resin and the like. Examples of the thermosetting resin include a melamine resin, a urea resin, a phenol resin, a ketone resin, an epoxy resin, a guanamine resin, and a rubber elastomer. These resins may be used alone or as a mixture of two or more types.When two or more types of resins are used, a blended or copolymerized version of two or more types of resins may be used, Those obtained by copolymerizing two or more kinds of monomers may be used. Also, not all of the resin particles need to be made of the same type of resin as a base material.
[0018]
All of the above-mentioned resins have excellent heat resistance and impact resistance, do not deteriorate even when heated when projected, and are hard to be powdered by the impact of projection, so that they can be used repeatedly. In addition, since dust is less likely to be generated, the environment for the blasting process is also favorable. In particular, plastic abrasives mainly composed of melamine resin are resistant to heat and impact, plastic abrasives mainly composed of urea resin are resistant to impact, and plastic abrasives mainly composed of phenol resin are resistant to heat. Plastic abrasives based on ketone resin are resistant to wear, plastic abrasives based on epoxy resin are resistant to heat and water, and plastic abrasives based on guanamine resin are impact resistant. In addition, a plastic abrasive containing polycarbonate as a main component has excellent heat resistance and impact resistance.
[0019]
The particle size of the plastic particles has a lower limit of 20 μm or more, preferably 100 μm or more, and an upper limit of 5000 μm or less, preferably 3000 μm or less, more preferably 1000 μm or less, and particularly preferably 850 μm or less.
[0020]
Next, in the recovery step 2, mixed particles of the abrasive injected to the object and the impurities generated by the blast processing are recovered from the blast room. This collection operation can be easily performed by appropriately tilting the bottom of the blast room toward the opening provided in the bottom.
[0021]
The mixed particles recovered in the recovery step 2 are transferred to the next dust removal step 3, where fine dust is removed by a dust collector. In this dust removal step 3, rough dust is removed via the line D by the cyclone dust collector.
[0022]
The mixed particles from which the fine dust has been removed in the dust removal step 3 are charged into a fixed-rate supply hopper tank so that the mixed particles can be supplied in a fixed amount in the fixed-rate supply step 4. It is preferable that the mixed particles supplied from the quantitative supply step 4 be transferred to a vibration quantitative supply step 5 in which a fixed amount is supplied while giving a minute vibration with a vibration feeder. Thereby, adhesion between particles can be prevented, and the sorting efficiency in the next sorting step 6 can be increased.
[0023]
The mixed particles that have passed through the quantitative supply step 4 or the vibration quantitative supply step 5 are transferred to a separation step 6 for dry specific gravity separation by a dry specific gravity separator. The dry specific gravity sorter separates particles relatively depending on a difference in specific gravity, and can adjust a separation point according to a mixing level of a mixed powder. Further, if a plurality of dry specific gravity sorters are used in the sorting step 6, more precise separation can be performed. As a specific gravity sorter, an air table (V-135) manufactured by Nitto Denki Engineering Co., Ltd. can be suitably used.
[0024]
When this air table is used as a specific gravity sorter, the mixed particles are supplied on the table of the specific gravity sorter, those with a higher relative specific gravity move to the upper part, and those with a lower relative gravity move to the lower part on the table, and near the exit. Separated. The mixing ratio of the mixture and the point to be separated can be arbitrarily adjusted.
[0025]
The usable abrasive separated in the sorting step 6 is supplied to the injection device of the blast processing step 1 via the line A, and is again subjected to the blast processing. On the other hand, the dust generated in the sorting step 6 is sent to the dust removing step 3 via the line B, and the impurity particles are discharged out of the system via the line C.
[0026]
In the present invention, the above-described series of processing steps, a known abrasive blasting apparatus equipped with a blasting machine for blasting the abrasives, and a blasting machine for injecting abrasives, The separation can be performed continuously by providing a dust collector, a fixed amount supply hopper, a vibration feeder, and a dry specific gravity separator.
[0027]
【Example】
Hereinafter, the present invention will be described based on examples.
Plastic projection material (melamine resin, particle size 850-500 μm, specific gravity 1.53, manufactured by Bridgestone Corp .: Miracle Gem (trade name)) (hereinafter abbreviated as “MG”) and alumina particles (particle size 50-2000 μm) In order to evaluate the possibility of separation due to the difference in specific gravity of the mixed powder (weight ratio 4: 1) with the specific gravity 3.5), the following dry type specific gravity sorter and operating conditions were used, and the following Table 1 was used. Each test shown in Table 2 was performed.
[0028]
(1) Dry specific gravity sorter: Air table V-135 manufactured by Nitto Denki Engineering Co., Ltd.
(2) Test conditions: vibration frequency 700 rpm, air volume 5.5 m ³ / min, end slope 6 °, side slope 5.5 °
[0029]
In Table 1 below, the processing amount / h is the processing speed of the dry-type specific gravity separator, the raw material input amount is the input amount of the mixed powder of MG and alumina particles under the processing speed, and the light side has a light specific gravity. The discharged weight on the side where the particles are discharged is shown, and the heavy side shows the discharged weight on the side where the heavy particles are discharged. The results of the particles discharged on the light side and the heavy side, respectively, magnified 25 times and visually observed are also shown in Table 1 below.
[0030]
[Table 1]

Note) The amount by which the total of the separated amount is reduced with respect to the raw material input amount is the sum of the amount collected in the dust collector at the time of separation and the amount scattered around.
[0031]
In Test Example 1, on the light side, portions apparently alumina particles were separated and removed. The same applies to Test Example 2, where the particles were separated at a mixing ratio of MG particles and alumina particles of 4: 1. Further, in Test Example 3, as in Test Example 1, the alumina particles were separated and removed. In Test Example 4, the light side of Test Example 3 was separated again. In Test Example 5, the processing speed of Test Example 1 was increased about 1.5 times.
[0032]
Next, the mixing ratio of the MG particles and the alumina particles on the light side and the heavy side in each test example is shown in Table 2 below. In Table 2, the specific gravity was measured with a specific gravity meter (electronic balance type specific gravity meter VIBRT DME-220) manufactured by Shinko Electronics Co., Ltd.
[0033]
[Table 2]

[0034]
From the mixing ratios shown in Table 2, it can be seen that the alumina particles were well separated on the light side of Test Examples 1 to 3. In particular, in Test Examples 1 and 2, it is separated to 5% or less. In Test Example 4, since a considerable amount of alumina particles had already been removed in Test Example 3, it can be seen that almost no alumina particles were present on both the light side and the heavy side. Test Example 5 shows that increasing the processing speed tends to decrease the separation ability.
[0035]
【The invention's effect】
As described above, according to the present invention, only the impurities are efficiently removed from the mixed particles of the abrasive after the abrasive is sprayed onto the object and blasted, and the impurities generated by the blasting. Can be removed.
[Brief description of the drawings]
FIG. 1 is a process chart showing an outline of a blast process of the present invention.
[Explanation of symbols]
1 Blasting process 2 Recovery process 3 Dust removal process 4 Quantitative supply process 5 Vibration quantitative supply process 6 Sorting process

Claims (6)

A blast processing step of blasting by injecting abrasives to the object,
A grinding step injected into the object, and a recovery step of recovering impurities generated by the blast processing,
A dust removal step of removing fine dust from the mixed particles collected in the collection step,
A quantitative supply step of quantitatively supplying the mixed particles from which fine dust has been removed by the dust removal step,
Sorting step of dry-type specific gravity sorting of the mixed particles supplied from the quantitative supply step,
A reuse step of reusing the blast material selected in the sorting step as an abrasive for the object,
A blast processing method comprising: The blasting method according to claim 1, wherein the dust generated in the sorting step is returned to the dust removing step. The blast processing method according to claim 1, wherein a vibration quantitative supply step is provided between the quantitative supply step and the sorting step, wherein a vibration quantitative supply step is performed in which the mixed particles quantitatively supplied from the quantitative supply step are supplied while quantitatively applying micro vibration. The blasting method according to any one of claims 1 to 3, wherein the abrasive is a plastic particle. The blasting method according to claim 4, wherein the plastic particles have a particle size of 20 to 5000 μm. An abrasive injection device for injecting an abrasive, a blast room for blasting with the injected abrasive, an abrasive recovered from the blast room, and an apparatus for separating impurities generated by the blast processing. In a blast processing device provided with a separation device,
The separation device, a dust collector, a quantitative supply hopper for quantitatively supplying mixed particles of the abrasive and impurities from which fine dust has been removed by the dust collector, and while applying vibration to the mixed particles supplied from the quantitative supply hopper. A blast processing apparatus comprising: a vibration feeder for supplying a fixed amount; and a dry-type specific gravity separator for selectively mixing the mixed particles supplied from the vibration feeder.

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