JP2011194451A - System for and method of managing system sand - Google Patents

Abstract

The present invention provides a green sand management system and a management method capable of controlling the amount of olitics.
SOLUTION: The collected sand after separation is collected for each product A to D, and the collected collected sand is individually stored in each collected sand containing portion 7A to 7D (collected sand containing means) for each product. Since the supply sand selected from the replenishment sand container (replenishment sand container means) 81-83 is added according to the products A to D to be molded, green sand having a desirable auxetics amount (%) Can be obtained stably.
[Selection] Figure 1

Description

  The present invention relates to a management system and a management method for green sand used for a mold.

  It is well known that the quality of castings is greatly influenced by the composition of green sand (system sand) which is a raw material of molds. Therefore, in order to stably obtain high-quality castings, the composition of green sand is controlled, that is, the content (%) of each component of green sand such as silica sand, bentonite, water, carbonaceous, and melt is controlled. There is a need to. An example of a method for managing the composition of green sand is disclosed in Patent Document 1.

  By the way, in the casting process, a coating layer called olitic is formed around sand particles and coked particles. Auritic is a porous body having fine voids, and the water taken into the porous body reduces the sensitivity of the green sand to water, thereby facilitating the management of the green sand. In addition, since the softening temperature is lower than that of quartz (silica sand), Auritics acts as a buffer against the thermal expansion of quartz by covering the surface of the quartz sand, and casting defects caused by the thermal expansion are eliminated. Can be prevented.

  On the other hand, when the amount of olitic is too small, the sand moisture easily escapes and the sand characteristics fluctuate greatly. In addition, casting defects due to the above-described thermal expansion of quartz are likely to occur. On the other hand, when the amount of olitic is excessive, the softening point of the green sand is lowered, so that defects such as rough skin and fusion are likely to occur in the product. As described above, it is extremely important to maintain the proper amount of olitic of the green sand in order to ensure the quality of the casting.

  However, the amount of auxetics of green sand is generally determined by the amount of olitic that increases due to the heat of fusion during casting, the amount of olitic of core sand mixed with recovered sand, and the amount of olitic contained in supplementary sand. In the past, recovered sand and core sand after mold separation has not been recovered for each product (sand frame or lot boundary is unclear). In addition, supplementary sand has a constant total green sand volume in the entire casting line. It is only put in to make it. In addition, the amount of core mixed into the green sand after mold release differs from product to product, and the core prevention technology and core separation technology have not reached the required level. Conventionally, it has been extremely difficult to control the amount of auxetics of green sand.

JP-A-9-057393

  Then, this invention was made | formed in view of the said situation, and it was made as a subject to provide the green sand management system and management method which can control the amount of olitics.

  In order to solve the above problems, a green sand management system of the present invention is a green sand management system used in a casting line, and is a green sand processing step for processing green sand that is a raw material of a mold, A sand regeneration treatment step for reclaiming the green sand containing the core, the green sand treatment step comprising: a collected sand containing means for individually collecting the collected sand collected after the separation of the mold; The replenishment sand containing means for individually storing a plurality of types of replenishment sand having different chicks, and the replenished sand selectively taken out according to the recovered sand to the recovered sand taken out from the recovered sand containing means Replenishment sand addition means for adding replenishment sand of the storage means.

  In order to solve the above-mentioned problems, a green sand management method of the present invention includes a green sand processing step for processing green sand that is a raw material of a mold, and a molding that forms a mold from the green sand processed by the green sand processing step. A sand reclaim processing step for reclaiming green sand or green sand containing core, and a green sand management method for use in a casting line, wherein A collected sand containing step individually accommodated, a replenished sand containing step individually containing a plurality of types of replenished sand having different auxetics amounts, and one product collected sand accommodated in the collected sand containing step, And a supplementary sand addition step of adding supplementary sand selected according to the recovered sand.

(Aspect of the Invention)
In the following, aspects of the invention that is recognized as being capable of being claimed in the present application (hereinafter referred to as claimable invention) will be exemplified, and each exemplified aspect will be described. Here, as in the claims, each aspect is divided into paragraphs, numbers are assigned to the respective paragraphs, and the descriptions of other paragraphs are cited as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combination of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiment, etc., and as long as the interpretation is followed, another aspect is added to the aspect of each section. Moreover, the aspect which deleted the component from the aspect of each term can also be one aspect of the claimable invention.
In the following items, each of items (1) to (4) corresponds to each of claims 1 to 4 described in the claims.

(1) A green sand management system used in a casting line, a green sand processing step for processing green sand as a raw material of a mold, and a sand regeneration processing step for regenerating green sand containing green sand or cores The green sand processing step includes individually collected sand containing means for individually collecting the collected sand collected after releasing the mold, and individually storing a plurality of types of replenished sand having different auxetics amounts. Replenishment sand containing means, and replenishment sand adding means for adding the replenishment sand of the replenishment sand containing means selectively taken out according to the recovered sand to the recovered sand taken out from the recovered sand containing means. A green sand management system.
According to the green sand management system described in this section, the replenishment sand selected according to the recovered sand is added to the recovered sand recovered for each product, in other words, the amount of saturated olitics (%) Selected from the multiple types of supplied sand that differ in the amount of auxetics (%) stored in the supplied sand storage means according to the amount of saturated auxetics (%) of the recovered sand. Added.
Therefore, in the aspect of this section, since a plurality of types of replenishment sand of various auxetics amounts (%) are prepared in advance in the replenishment sand storage means, the replenishment sand to be added and its addition rate according to the recovered sand By selecting (%), it is possible to stably obtain green sand having a desirable auxetics amount (for example, 23%). Thereby, the casting defect resulting from a casting_mold | template is avoided and the quality of a casting can be ensured.
In addition, the estimated value P (%) of the saturation ohmics amount (%) can be derived by the following formula 1.
P = ΔY / X + Q (Formula 1)
However, in Formula 1, ΔY is the amount of aurix (%) that increases due to pouring, X is the addition rate (%) of the supplementary sand, and Q is the amount of auricix (%) of the supplementary sand.

(2) The green sand management system according to (1), wherein the plurality of types of replenishment sand includes reclaimed sand extracted from each processing step of the sand reclaim processing step.
The reclaimed sand taken out from each processing step of the sand reclamation process varies in the amount (%) of auxilix depending on the treatment process that has been taken out, that is, what treatment has been performed in the sand reclamation process. Therefore, according to the green sand management system described in this section, by storing the reclaimed sand taken out from each processing step of the sand regenerating process step as replenishment sand in the replenishment sand containing means, %) Replenishment sand can be prepared.

(3) Multiple types of replenishment sand are polished from reclaimed sand obtained by polishing raw green sand, regenerated sand obtained by magnetically treating raw green sand, and raw sand containing roasted cores. (1) and (2) green sand management system including reclaimed sand obtained by performing at least one magnetic separation process.
According to the green sand management system described in this section, for example, reclaimed sand obtained by polishing green sand (dry regeneration → fine powder removal) can be obtained by adjusting the processing time (regeneration time). The amount can be adjusted to 13-23 (%). Moreover, the reclaimed sand obtained by subjecting green sand to magnetic separation can be adjusted to 26-60% by adjusting the magnetic force, treatment time, and the like. Moreover, the reclaimed sand obtained by carrying out the polishing treatment and the magnetic separation treatment only once for the green sand containing the roasted core can be adjusted to 45 (%) in the auxetics amount, By repeatedly carrying out the polishing treatment and the magnetic separation treatment, it is possible to obtain regenerated sand having a low autistic value of 6 to 8 (%) as in the case of fresh sand.
In the embodiment of this section, the sand processing and magnetic separation processing of the green sand can use the processing equipment of the sand regeneration processing step, so there is no need to newly install these equipment (magnetic separation equipment and polishing equipment). An increase in cost can also be suppressed.

(4) A green sand management method used in a casting line, which is a green sand processing step for processing green sand that is a raw material of a mold, and a sand regeneration processing step that regenerates green sand containing green sand or a core. The green sand processing step includes a recovered sand storing step for individually storing recovered sand recovered after releasing the mold, and a plurality of types of replenished sand having different auxetics amounts. A green sand comprising a replenishment sand containing step, and a replenishment sand addition step of adding replenishment sand selected according to the recovered sand to the recovered sand of one product accommodated in the recovered sand accommodation step Management method.
According to the green sand management method described in this section, the replenishment sand selected from the replenishment sand stored in the replenishment sand storage step according to the recovered sand is added to the recovered sand recovered for each product. In other words, the recovered sand with saturated oolytics (%) is different from the multiple types of supplied sand that differ in the auxetics (%) stored in the supplied sand storage step. Replenishment sand selected according to the amount (%) is added.
Therefore, in the aspect of this item, since a plurality of types of replenishment sand of various auxetics amounts (%) are prepared in advance by the replenishment sand accommodation step, the replenishment sand to be added and its addition rate ( %), It is possible to stably obtain green sand having a desirable auxetics amount (%). Thereby, the casting defect resulting from a casting_mold | template is avoided and the quality of a casting can be ensured.
Note that the estimated value P (%) of the saturated orchid amount (%) can be derived from the above-described Equation 1.

  ADVANTAGE OF THE INVENTION According to this invention, the green sand management system and management method which can control the amount of olitics can be provided.

It is a figure which shows schematic structure of the casting line containing the green sand management system of this embodiment. It is a figure showing the relationship between the replenishment sand addition rate (%) of a prior art, and the amount of saturation olitics (%). FIG. 3 is a chart showing element conditions at points (products) A, C, and D that are out of a preferred range of the amount (%) of FIG. It is a chart which shows the conditions of the element in this embodiment corresponding to each product A, C, D of FIG.

An embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a schematic configuration of a casting line including the green sand management system of the present embodiment. In this casting line, green sand as a mold raw material is processed in the green sand processing step 1 and then shaped into a target product mold together with the core (molding step 17). The formed mold is separated in the mold releasing step 2 in the green sand processing step 1 through the steps 21 to 24 of the pouring water 21, the frame cooling 22, the frame extraction 23, and the primary cooling 24. The surplus sand generated here is mixed with the core separated from the recovered sand (green sand) in the core separation step 5 described later, sand 25 (green sand) attached to the coarse material (molded product), and the like. Then, after being regenerated in several patterns, which will be described later, in the sand regeneration process step 11, the sand is supplied to specified replenishment sand storage units 81-83, which will be described later, in the green sand processing step 1.

  The green sand management system according to this embodiment includes the green sand processing step 1 and the sand regeneration processing step 11 described above. The green sand treatment process 1 cools the recovered sand from which the iron pieces are separated (removed), in addition to the mold releasing process 2 described above, as well as the iron piece separating process 3 for separating the iron pieces from the collected sand (collected sand) after releasing the mold. Sand cooling process 4 to perform, core separation process 5 to separate the core contained in the cooled recovered sand, and recovered sand from which the core has been separated (removed) is collected and mixed for each frame (each product) Each step of the mixing step 6 is included. As described above, the core separated from the recovered sand in the core separation step 5 is sent to the sand regeneration treatment step 11 as surplus sand.

  The green sand treatment process 1 includes a plurality of (4 in FIG. 1 corresponding to the products A to D) recovered sand storage units that individually store the recovered sand (green sand) from which the core has been separated. 7A-7D (collected sand storage means). For example, a silo type is adopted as each of the collected sand containing portions 7A to 7D. The collected sand of one product mixed in the mixing step 6 is transported to the designated collected sand accommodating portions 7A to 7D by a belt conveyor or the like based on the control of the control device or the like. In addition, the green sand treatment process 1 is a process of regenerating sand (replenishment sand) taken out from each treatment process described later of the sand regeneration treatment process 11 and preliminarily kneaded by the kneader 9, in other words, the amount of olitics ( %) A plurality of (three in FIG. 1) replenishment sand accommodating portions 81 to 83 (replenishment sand accommodating means). Note that one type of reclaimed sand preliminarily kneaded by the kneading machine 9 is conveyed to a designated replenishment sand accommodating portion 81 to 83 by a belt conveyor or the like.

  The sand regeneration process 11 includes a roasting process 12, a dry regeneration process 13, a magnetic separation process 14 and a fine powder removing process 15. In addition, since each process 12-15 is a well-known technique in the expert, detailed description of each process 12-15 is abbreviate | omitted here. Here, some regeneration process patterns implemented in the sand regeneration process step 11 will be described.

(Reproduction process 1)
In the regeneration process 1, the excess sand roasted in the roasting process step 12 is repeatedly subjected to a dry regeneration process (polishing process) in the dry regeneration process 13 and a magnetic separation process in the magnetic separation process step 14 for a predetermined time, and then fine powder is removed. It is the reproduction | regeneration processing pattern which implements fine powder removal at the process 15. FIG. In this reclaimed treatment pattern, reclaimed sand 1 (core reclaimed sand) having an auxetics amount of 7 (%) was obtained.
(Reproduction process 2)
The regeneration process 2 is a regeneration process pattern in which the dry sand in the dry regeneration process 13 and the magnetic separation process in the magnetic separation process 14 are performed only once on the surplus sand roasted in the roasting process 12. In this reclaimed treatment pattern, reclaimed sand 2 (magnetically adhering sand) having an olitic content of 45 (%) was obtained.
(Reproduction process 3)
The regeneration process 3 is a regeneration process pattern in which the dry sand in the dry regeneration process 13 and the fine powder removal in the fine powder removal process 15 are performed on the surplus sand (raw sand) that has not been subjected to the roasting process in the roasting treatment process 12. (Polishing process). In this reclaimed treatment pattern, reclaimed sand 3 (polished sand) having an olitic content of 13 to 23 (%) was obtained. Note that in this regeneration processing pattern, the amount (%) of Aurichix can be adjusted by adjusting the processing time of the dry regeneration processing.
(Reproduction process 4)
The regeneration process 4 is a regeneration process pattern in which the magnetic separation process of the magnetic separation process step 14 is performed on surplus sand (raw sand) that does not include the core roasted in the roasting process step 12. In this reclaimed treatment pattern, reclaimed sand 4 (magnetically adhered sand) having an auxetics amount of 26 to 60 (%) was obtained. In this reproduction processing pattern, it is possible to adjust the amount (%) of the orifice by adjusting the magnetic force and processing time of the magnetic separation process.

  In the present embodiment, as described above, the reclaimed sand 1 to 4 prepared by each of the regenerating treatments 1 to 4 and fresh sand having an auxetics amount of 7 (%) are selectively designated. It is put in and accommodated in the accommodating parts 81-83. Although detailed description is omitted because it is a well-known technique, in the present embodiment, the required amount of recovered sand and replenished sand is required from each of the recovered sand accommodating portions 7A to 7D and each of the replenished sand accommodating portions 81 to 83. It is configured so that it can only be weighed out.

Next, the operation of this embodiment will be described.
Prior to describing the operation of the present embodiment, the prior art will be described for the purpose of facilitating understanding of the operation of the present embodiment. FIG. 2 shows the relationship between the replenishment sand addition rate (%) and the saturated orificix amount (%) when the replenishment sand is only core regenerated sand. In the figure, the increased amount (%) of Aurichix is the amount (%) of Aurichix produced (increased) by one casting (heating). The supplementary sand addition rate (%) is the ratio of the supplementary sand added to the recovered sand. It should be noted that the replenishment sand (recycled sand for core) used here has an olitic amount of 7 (%).
Furthermore, the estimated value P (%) of the saturation ohmics amount (%) can be derived by the following Equation 1.
P = ΔY / X + Q (Formula 1)
However, in Formula 1, ΔY is the amount of aurix (%) that increases due to pouring, X is the addition rate (%) of the supplementary sand, and Q is the amount of auricix (%) of the supplementary sand.

  As shown in FIG. 2, point A (product A) is set when the target auxetics amount is set to 23 (%) and the preferred auxetics amount (allowable auxetics amount) is set to 18 to 28 (%). , C point (product C) and D point (product D) are outside the range of the preferred auxetics amount (%), that is, the auxetics amount (%) is controlled (adjusted to the preferred auxetics amount (%)). Is impossible). This is because at point A (product A), the amount of increased orificis (%) is large and the supplementary sand addition rate (%) is small. On the other hand, at the point C (product C) and the point D (product D), it is caused by a small increase in the amount of autistics (%) and a relatively large supplemental sand addition rate (%). FIG. 3 shows this numerically.

  In contrast, in the present embodiment, the collected sand is collected for each of the products A to D (collection step), and the collected sand storage units 7A to 7D (the collected sand) in which the collected sand collected for each product is designated. (Recovered sand accommodation step). Then, each of the replenishment sand storage portions (replenishment sand storage means) 81 to 83 stores replenishment sand having an auxetics amount of 7 (%), 15 (%), and 20 (%), respectively (replenishment sand storage) Step). Here, the replenishment sand having an auxetics amount of 7 (%) is the above-mentioned reclaimed sand 1 (recycled sand for cores), and the replenishment sand having an auxetics amount of 15 (%) and 20 (%) is The above-mentioned recycled sand 3 (polished sand) having different regeneration processing times.

  In the present embodiment, as shown in FIG. 4, in the product A, the reclaimed sand 81 is changed without changing the replenishment sand 81, that is, the reclaimed sand for core is 7 (%). By adding under the condition of 9 (%) (replenishment sand addition step), it was possible to set the saturation ollitics amount to the target value of 23 (%). Further, in the product C, the supplementary sand addition rate is maintained at 2.0 (%), and the supplementary sand 82, that is, polishing sand (regenerated sand 3) having an olitic content of 15 (%) is added. (Supplementary sand addition step), the saturation olitics amount could be set to the target value of 23 (%). Similarly, in the product D, the supplementary sand addition rate is maintained at 3.3 (%), and supplementary sand 83, that is, polished sand (regenerated sand 3) having an auritic amount of 20 (%) is added. (Replenishment sand addition step), the saturation olitics amount could be set to the target value of 23 (%).

This embodiment has the following effects.
According to the present embodiment, the collected sand after separation is collected for each of the products A to D, and the collected collected sand is individually collected for each product for each collected sand containing portion 7A to 7D (collected sand containing means). The supplementary sand selected from the supplementary sand accommodating parts (supplementary sand accommodating means) 81 to 83 is added according to the products A to D that are housed and molded, so that the desired auxetics amount (%) It is possible to stably obtain the green sand, avoiding casting defects such as rough skin and fusion mainly due to the mold, and ensuring the quality of the casting.

In addition, embodiment is not limited above, For example, you may comprise as follows.
In the present embodiment, the green sand processing step 1 is configured by combining the four green sand storage units 7A to 7D and the three replenishment sand storage units 81 to 83, but these combinations may be combined as appropriate. Can do.

DESCRIPTION OF SYMBOLS 1 Green sand processing process, 2 type | mold spreading | diffusion process, 7A-7D Recovery sand accommodating part (collected sand accommodating means), 81-83 Supplementary sand accommodating part (supplementary sand accommodating means), 11 Sand reproduction processing process, 12 Roasting process process , 13 Dry regeneration process (polishing process), 14 Magnetic separation process process, 15 Fine powder removal process (fine powder removal process)

Claims (4)

A green sand management system used in a casting line,
A green sand processing step for processing green sand, which is a raw material of the mold, and a sand regeneration processing step for regenerating green sand containing green sand or core,
The green sand processing step is
Collected sand containing means for individually collecting the collected sand collected after the separation of molds, replenished sand containing means for individually containing a plurality of types of supplied sand having different auxetics amounts, and the collected sand contained And a replenishment sand addition means for adding the replenishment sand of the replenishment sand storage means selectively taken out according to the recovered sand to the recovered sand taken out from the means. The plurality of types of supplementary sand are:
The green sand management system according to claim 1, comprising reclaimed sand extracted from each processing step of the sand reclaim processing step. The plurality of types of supplementary sand are:
Recycled sand obtained by polishing raw green sand, regenerated sand obtained by magnetically treating raw green sand, and green sand containing a roasted core, the polishing treatment and the magnetic separation treatment at least once. 3. The green sand management system according to claim 1 or 2, characterized in that it includes reclaimed sand obtained by implementation. A green sand management method used in a casting line,
A green sand processing step for processing green sand, which is a raw material of the mold, and a sand regeneration processing step for regenerating green sand containing green sand or core,
The green sand processing step is
A recovered sand containing step for individually collecting the collected sand collected after the separation of molds, a replenished sand containing step for individually containing a plurality of types of replenished sand having different auritic amounts, and the collected sand containing A green sand management method comprising: a replenishment sand adding step of adding replenishment sand selected according to the recovered sand to the recovered sand of one product stored in the step.

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