JP2002103000A - Treatment method for main mold green sand and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment method for recovery sand easy in moisture control and addition of a bond, free of causing a defect, and compact in a recovery means, and a device therefor. SOLUTION: The treatment method for a main mold green sand obtained by separating/recovery of a green sand main mold after casting, wherein the green sand main mold after casting is separated one by one into a portion not subjected to a thermal effect to molten cast and a portion subjected to the thermal effect to be stored in a different storing means respectively, the separated sand stored by each separated sand storing means is recovered into different recovered sand storing means respectively with time difference and by same route, then after the two kinds of the recovered sand obtained in this way are blended at the prescribed rate, moisture control is conducted to be used as the casting sand.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for treating a green sand obtained by separating and recovering a green sand main mold after casting (hereinafter abbreviated as a main mold).

[0002]

2. Description of the Related Art Conventionally, as a method for treating recovered sand, as disclosed in JP-A-10-249482, sand whose casting main mold has been exposed to a high temperature by a molten metal and sand outside thereof have been disclosed. There is a method in which water and a binder are added to sand exposed to high temperature and then mixed with outside sand to regenerate the sand.

[0003]

However, in the above-mentioned conventional method for treating recovered sand, it is difficult to adjust the water content and to add a binder to regenerate the foundry sand, and the main method using the regenerated foundry sand is difficult. When cast in a mold, there is a problem that defects may occur in the casting. Separate the heat-affected and non-heat-affected sand,
It is a large facility to collect by another route.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to facilitate the adjustment of water content and the addition of a binder for regenerating molding sand, and the main mold formed by reclaimed molding sand. Casting does not cause defects in castings,
An object of the present invention is to provide a method and an apparatus for treating recovered sand in which the recovery means does not increase.

[0005]

Means for Solving the Problems In order to achieve the above object, a method for treating a green sand according to the present invention comprises a method for separating a green sand main mold after casting and recovering the green sand obtained from the main sand. A method of processing, in which the raw sand main mold after casting is separated one by one into a portion not affected by the heat of the molten metal and a portion affected by the heat of the molten metal, and is not affected by the heat of the molten metal. The part and the part affected by the heat of the molten metal are stored in separate separated sand storage means, respectively, and the separated sand stored in each separated sand storage means is separated from each other by the same route with a time difference. After the two types of recovered sand are blended at a predetermined ratio, at least the water content is adjusted and used as foundry sand. According to the present invention, by collecting the same path with a time difference, it is easy to adjust the water content and to add a binder to regenerate as foundry sand,
Even when casting is performed using a main mold made of recycled casting sand, there are advantages that casting defects do not occur and that the recovery equipment does not become large.

In order to achieve the above object, a main green sand recovery processing apparatus according to the present invention is an apparatus for processing recovered sand obtained by separating and collecting a green sand main mold after casting. Separation and storage means for separating and storing the raw sand main mold after casting into portions not affected by the heat of the molten metal and portions affected by the heat of the molten metal one by one, and heat of the separated and stored molten metal. Recovery means for separately recovering the unaffected part and the heat-affected part of the separated and stored molten metal,
Recovered sand storage means for separately storing a heat-insensitive part of the separated and stored molten metal and a heat-affected part of the separated and stored molten metal recovered by the recovery means, Clay moisture adjusting means for adding a binder and adjusting the moisture content of the heat-affected recovered sand, and the recovered sand adjusted by the clay moisture adjusting means and the recovered sand not affected by the heat at a predetermined ratio. It is characterized by comprising a mixing means for mixing and a kneading means for kneading by adjusting the water content. According to the present invention, it is not necessary to use a plurality of collecting means, and thus there is an advantage that the size of the collecting equipment is not increased. In addition, it is easy to adjust the water content and add a binder to regenerate the molding sand, and no defects are found in the casting even when the molding is performed with the main mold made of the reclaimed molding sand.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a method of separating a main mold after casting into a part not affected by the heat of the molten metal and a part affected by the heat of the molten metal is as follows. This can be achieved by applying a negative pressure to the stored airtight structure. In other words, the main mold immediately after casting is airtightly surrounded, and the main mold is negatively pressurized in the airtight structure housing the main mold. This water is boiled, and the part of the molten metal that is not affected by heat is broken down and separated.

[0008] Immediately after the casting is a point in time when the molten metal in the main mold is solidified to form a casting. Separating the green sand main mold after casting into a part that is not affected by the heat of the molten metal and a part that is affected by the heat of the molten metal one by one, so that these two parts intersect with each other. Can be prevented. Furthermore, there is no need to add unnecessary additives,
Adjustment of moisture becomes relatively easy. In addition, when a defective product occurs in a casting material due to separation of each mold, it becomes easy to specify each condition such as a mold and a molten metal, and a countermeasure becomes easy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail with reference to FIG. The apparatus according to the embodiment of the present invention, as shown in the flowchart of FIG. 1, is an apparatus for processing a main green sand obtained by separating and collecting a green sand main mold after casting. ,
Separating means for separating the main mold after casting into a part not affected by the heat of the molten metal and a part affected by the heat of the molten metal one by one, and a separating sand storage means for storing (primary separated sand hopper) And a secondary separation sand hopper).

Downstream of the separating and storing means, there is provided a collecting means comprising a magnetic separator, a screen, a water adding device, a sand cooler and a connecting means thereof. The portion of the melt that has not been affected by heat and the portion of the separated and stored melt that have been affected by heat can be separately collected.

Downstream of the recovery means, two recovered sand storage means (two sand bins) are provided, and a part of the separated and stored molten metal which is not affected by heat is separated from the separated and stored part. The heat-affected portion of the stored melt is stored separately.

Further, a clay moisture adjusting means is provided downstream of the recovered sand storage means, so that a binder can be added to the recovered sand and the moisture can be adjusted.

Further, downstream of the clay moisture adjusting means, a blending means for mixing the recovered sand adjusted by the clay moisture adjusting means and the recovered sand which has not been affected by heat at a predetermined ratio, and a moisture adjustment is performed. And a kneading means for kneading.

Hereinafter, the operation of the apparatus according to the present invention will be described. As shown in FIG. 1, in the method of treating the main mold green sand, first, the main mold molded by a molding machine is cast, and then the main mold after casting is housed in an airtight structure. In addition, around the casting material in the main mold, a layer (water condensation layer) is formed which is heated by the heat of the casting material and has a high temperature and a large amount of moisture collected therein. weak. Then
The air is sucked from the airtight structure and the pressure inside the airtight structure is rapidly reduced. Then, the boiling point of the water in the entire main mold including the water in the water condensing layer is lowered and the water boils, and accordingly, the portion of the main mold that is not affected by the heat of the molten metal is collapsed.

As a result, the main mold is separated into a portion not affected by the heat of the molten metal and a portion affected by the heat of the molten metal (primary dispersion). The portion of the molten metal that has not been affected by the heat is broken down and separated one by one as described above, and then recovered as recovered sand. Next, the recovered sand is pulverized by an agglomerator into particles, and once stored in a primary separation sand hopper serving as separation sand storage means.

On the other hand, the part affected by the heat of the molten metal is
Since it adheres to the casting material, it is separated from the casting material by vibration or the like (secondary dispersion). The heat-affected portion of the separated molten metal is temporarily stored in a secondary separated sand hopper as another separated sand storage means.

Subsequently, the primary separated sand stored in the primary hopper is removed from the metal pieces by a magnetic separator, sieved to a predetermined size by a screen, and water is added if water is insufficient. Then, it is cooled to an appropriate temperature by a sand cooler and temporarily stored in a sand bin as a recovered sand storage means.

After the primary separated sand is collected, the secondary separated sand stored in the secondary hopper is separated by a time difference, and the metal pieces are removed by a magnetic separator along the same path, and are then reduced to a predetermined size by a screen. After sieving, if water is insufficient, water is added. Then, it is cooled to an appropriate temperature by a sand cooler and temporarily stored in a sand bin as another storage means for collected sand. In this way, different types of separated sand are treated with a time difference on the same route, but the primary separated sand and
The recovery process differs from the next separation sand. For example,
Water is added according to the temperature and moisture value of the recovered sand. Also,
The vibration conditions of the magnetic separator and the screen may be changed. By doing so, it is possible to adjust the sand before the collected sand storage means. For this reason, subsequent adjustment processing can be simplified.

Next, the two types of recovered sand stored in the two sand bins are cut out of the sand bins in required amounts, respectively, and introduced into a kneading machine. Subsequently, kneading is performed while adding water and a binder. It is kneaded by a machine and used as foundry sand. The binder and water may be preliminarily kneaded before being put into the kneader from the sand bin.

In this embodiment, after the primary separated sand is recovered, the secondary separated sand is recovered, but the reverse is also possible. In this case, switching can be performed by a timer, a level switch, or the like. In addition, the separated sand storage means may be integrated with the separated sand storage means as long as it can store the primary separated sand and the secondary separated sand separately. Similarly, the recovered sand storage means may have an integral structure.

[0021]

As is apparent from the above description, the method according to the present invention is a method for treating the green sand obtained by separating and recovering the green sand main mold after casting, and is a method for treating the green sand after casting. The raw sand main mold is separated into a part that is not affected by the heat of the molten metal and a part that is affected by the heat of the molten metal one by one, and the part that is not affected by the heat of the molten metal and the part that is affected by the heat of the molten metal. Each part is stored in separate separated sand storage means, and the separated sand stored in each separated sand storage means is collected in different recovered sand storage means along the same route with a time difference. After blending the recovered sand at a predetermined ratio, the water is adjusted and used as foundry sand, so it is easy to add moisture and a binder to regenerate as foundry sand,
Even if casting is performed using a main mold made of recycled casting sand, no defects in the casting are generated, and no large-scale equipment is provided. Further, the apparatus according to the present invention separates the green sand main mold after casting.
A device for processing recovered sand obtained by recovery, separating and storing the raw sand main mold after casting into a part not affected by the heat of the molten metal and a part affected by the heat of the molten metal one by one. Separating and storing means, a collecting means for separately collecting a heat-insensitive part of the separated and stored molten metal and a heat-affected part of the separated and stored molten metal, and the collecting means Recovered sand storage means for separately storing a heat-insensitive part of the separated and stored molten metal and a heat-affected part of the separated and stored molten metal, Clay moisture adjusting means for adding a binder and adjusting the water content of the received recovered sand, and mixing the recovered sand adjusted by the clay water adjusting means and the recovered sand not affected by heat in a predetermined ratio. Kneading with means and moisture adjustment With the kneading means, it is easy to adjust the water content and add a binder to regenerate as foundry sand, and casting defects may occur even when casting with the main mold using reclaimed foundry sand. It has excellent practical effects such as no large-scale facilities.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

Continued on the front page (72) Inventor Takehiko Matsumoto 3-1 Honohara, Toyokawa-shi, Aichi Prefecture Shinto Kogyo Co., Ltd. (72) Inventor Yasuyuki Makino 3-1 Honohara, Toyokawa-shi, Aichi Shintokogyo Co., Ltd. (72) Inventor Yasunori Yoshida 3-1 Honohara, Toyokawa City, Aichi Prefecture Shinto Kogyo Co., Ltd.

Claims (7)

[Claims] 1. A method for treating a green sand main mold obtained by separating and recovering a green sand main mold after casting, wherein the green sand main mold after casting is affected by the heat of the molten metal one by one. The part not affected by the heat of the molten metal and the part affected by the heat of the molten metal are separated, and the part that is not affected by the heat of the molten metal and the part that is affected by the heat of the molten metal are stored in separate separated sand storage means. The separated sand stored in the separated sand storage means is collected in different recovered sand storage means along the same route with a time difference, and the two kinds of recovered sand thus obtained are blended at a predetermined ratio, and then the water is adjusted at least. And a method for treating main green sand which is used as foundry sand. 2. The method according to claim 1, wherein a recovery process for the separated and stored heat-affected sand is different from a recovery process for the separated and stored heat-unaffected sand in the same path. Main method of processing green sand. 3. The method for treating main green sand according to claim 2, wherein in the collecting process in the same path, water is added according to the temperature and the water value of the collected sand. 4. After adding a binder and adjusting the water content to the heat-affected sand separated and stored and recovered, the heat-unaffected sand separated and stored and mixed at a predetermined ratio as it is. The method for treating a green sand according to any one of claims 1 to 3, wherein: 5. A method in which a portion of the molten metal that is not affected by heat and a portion of the molten metal that is affected by heat are respectively recovered in separate recovered sand storage means, and the two types of recovered sand thus obtained are subjected to a predetermined method. The method for treating main green sand according to any one of claims 1 to 4, wherein a binder is added after mixing at a ratio. 6. The method of separating the green sand main mold after casting into a part not affected by the heat of the molten metal and a part affected by the heat of the molten metal, The method according to any one of claims 1 to 5, wherein the method is achieved by applying a negative pressure to the sealed airtight structure. 7. An apparatus for treating recovered sand obtained by separating and recovering a green sand main mold after casting, wherein a part of the green sand main mold after casting is not affected by the heat of the molten metal one by one. Separating and storing means for separating and storing the heat-affected portion of the molten metal and the heat-affected portion of the separated and stored melt and the heat-insensitive portion of the separated and stored melt. Recovery means for separately recovering the part and the part which is not thermally affected by the separated and stored molten metal and the part which is thermally affected by the separated and stored molten metal which is recovered by the recovery means. And a clay moisture adjusting means for adding a binder and adjusting the moisture content of the heat-affected recovered sand, and the recovered sand adjusted by the clay moisture adjusting means and the heat effect. Distribution of recovered sand that has not been subjected to An apparatus for recovering main green sand, comprising: mixing means; and kneading means for performing kneading by adjusting water content.