KR20190087847A - Binder for molding sand using tapioca - Google Patents

Abstract

The present invention relates to a binder for molding sand using tapioca and a method for manufacturing the same and, more specifically, to a binder and a method for manufacturing a binder capable of improving a caking property and moldability of molding sand by using only tapioca without a separate additive. The method for manufacturing a binder comprises: a first step of precipitating tapioca powder in a sulfurous acid solution and separating and obtaining precipitated tapioca starch; a second step of drying the obtained tapioca starch and obtaining a tapioca pressed product by supplying and pressing the tapioca starch in a pressing device; a third step of obtaining a tapioca chip by cutting the tapioca pressed product to a predetermined size; and a fourth step of supplying the tapioca chip to a cylinder and puffing the same.

Description

Technical Field [0001] The present invention relates to a briquette for molding using tapioca,

More particularly, the present invention relates to a method for producing a dot-payment and a dot-payment method for improving the cohesiveness and moldability of a foundry sand by utilizing only tapioca without any additive, .

In the past, large-sized water-based casting production was dominant, and the main failure type of the casting product was mostly due to the high-temperature molten metal poured into the casting mold.

For example, when a high-temperature molten bath (about 1,500 ° C) is transferred to a mold formed by molding sand molding, the surface of the mold rapidly dries. As the expanded sand is blown or cracked, .

As a result, there has been a problem in that the sand of the foundry sand on the dried surface is swept away by the molten metal injected, the mold collapses, and the dropout phenomenon that the edge falls off. Therefore, in order to prevent this, To create and use.

However, as the casting parts have been replaced with light alloy products such as aluminum, small and thin casting products have become popular, and these types of casting molds have been greatly reduced in the type of defects that the molds expand or burst due to the heat of the casting molten metal, There is a significant increase in the number of types of defects that are caused by the drying of sand sand by heat.

In the past, organic pasteurization was effective for defective types such as expansion, cracking, and bursting due to heat of a molten metal. However, the effect of improving the surface of a mold that has been dried by heat and has been smashed is insufficient and development of a better casting sand .

For this reason, we have reached a point where we need a new sand casting agent that acts to keep the moisture to a minimum so that the casting sand does not get loose even under low moisture content.

In particular, the organic point-of-payment used in the past was made through complicated processes by adding various additives in order to directly deform the mold (expansion, cracking, rupture, etc.) and releasing force due to the heat of the molten metal, Which is the cause of the glass water-molding sand supplementary material.

Therefore, by keeping the glass water longer, it is possible to find the most suitable material for supplementing the lack of moisture of the foundry sand, and by processing it in a proper way, it gives soft resilience to the hard mold and by increasing the toughness to the mold with low moisture content, Research is needed to prevent any external stimuli from being easily distorted.

Korean Registered Patent No. 10-0071468, Mar. 04, 1994 Registered as a person. Korean Registered Patent No. 10-0784319, December 4, 2007 Registered as a person.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a casting use point payment using tapioca and a method of manufacturing the casting using the tapioca, .

In order to accomplish the above object, the present invention provides a method for preparing tapioca starch, comprising: a first step of precipitating tapioca powder in a sulfurous acid aqueous solution and then separating and precipitating the precipitated tapioca starch; A second step of drying the obtained tapioca starch and then pressing it while supplying it to a press to obtain a pressed tapioca; A third step of obtaining a tapioca chip while cutting the tapioca squeeze into a predetermined size; And a fourth step of supplying the tapioca chips to the cylinder while fuffing the tapioca chips. The present invention also provides a method of manufacturing the tap water using the tapioca.

Preferably, the injection nozzle is provided inside the presser of the second step, and the spray nozzle is supplied with the primary steam from the outside, reheating it, and spraying the secondary steam into the secondary steam, so that the tapioca starch is compressed .

Preferably, the cylinder of the fourth step includes a cylinder body; A charging port formed at one side of the cylinder body for charging the tapioca chip; A screw formed inside the cylinder body and rotated by a motor to compress and transport the tapioca chip from one side to the other side; A droplet space formed on the other side of the screw to form a tapioca paste with the tapioca chips transferred from the screw being accumulated; And a discharge port formed on the other side of the cylinder main body and discharged through fuffing of the tapioca paste while passing through the droplet space.

Preferably, the tapioca paste is discharged at a pressure of 8 to 12 kg / cm 2 at the discharge port.

Preferably, the fourth step further comprises a fifth step of crushing the expanded tapioca paste and passing it through a screen net.

In order to accomplish the above object, the present invention also provides a casting use point payment using tapioca, which is manufactured by the above-described manufacturing method.

According to the present invention, there is provided a method for preparing a casting using tapioca and a method for manufacturing the same, which prevents drying of the casting sand during the failure type of the casting product due to tapioca, There is an effect that can be mass-produced at low cost.

1 is a flowchart according to a preferred embodiment of the present invention;
FIG. 2 is a schematic view of a compactor according to a preferred embodiment of the present invention. FIG.
3 is a cylinder according to a preferred embodiment of the present invention.

The present invention relates to a new point payment system using tapioca so that moisture can be maintained for a longer period of time in order to reduce the occurrence of defects caused by drying of foundry sand among defective types of cast products, To provide a method for producing a point-payment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart according to a preferred embodiment of the present invention. As shown in FIG. 1, the casting use point payment using the tapioca of the present invention may be performed in a first step S10, a second step S20, a third step S30, a fourth step S40, S50). ≪ / RTI >

First, the first step is a step of precipitating tapioca powder in a sulfurous acid aqueous solution, followed by separating the precipitated tapioca starch. (S10)

First, let me explain the background in which tapioca is produced. The cassava, originating from the Americas tropical region, is cultivated to obtain tubers throughout the tropics. These tubers make cassava flour, bread, alcoholic beverages, and tapioca. Cassava is a perennial plant that has prominent fan-shaped leaves, similar to castor leaves, but 5- to 9-fold deeper and the fleshy root (roots) reminds of a dahlia stem. Foods such as West Africa's fufu and bama mush in Jamaica are also made into cassava. Other cassava products include Alcoholic beverages made by Indians in South America, cassava cakes in Yucatan powder, and Tapioca, the only cassava product in the northern market.

Especially, roots of cassava contain 20 ~ 30% of starch, and after washing the starch with water to precipitate it, it is dried, and the tapioca obtained by drying is crushed to make tapioca powder. The tapioca powder thus produced is very good in viscosity and has a corresponding elasticity even without mixing conventional starch, rice starch and the like, which is why the present invention is applied.

As described above, unlike the conventional method in which a mixture of corn, starch, and other additives is mixed, only the tapioca powder is used to make the tapioca starch, so that it is unnecessary to add any other additive. can do.

At this time, if the tapioca starch obtained in the first step is less than 180 meshes, the particles may be too fine to make a uniform tapioca squeeze product without defects, but since the particle size is too small, It is inefficient because it increases.

On the other hand, when the tapioca starch exceeds 200 mesh, the particles are too large to smooth the tapioca squeeze, so that the tapioca starch preferably has a size of 180 to 200 mesh.

To summarize, the tapioca starch obtained by precipitating tapioca powder in an aqueous sulfurous acid solution at a concentration of 0.25 to 0.3% for 30 to 50 hours (preferably 48 hours) is a starch which is a vegetable starch and has a very high viscosity, The drying speed is slower than that of the viscous solution, and the elasticity and toughness are further improved.

Next, the second step is a step of drying the obtained tapioca starch, and then supplying the compressed tapioca starch to the compactor 100 to obtain a compressed tapioca product. (S20)

That is, the second step is to dry the tapioca starch after immersing it in a sulfurous acid aqueous solution, and then to supply the compressed tapioca starch to the compactor 100 and compressing the compressed tapioca starch.

2 is a compactor 100 according to a preferred embodiment of the present invention. 2- (a) shows the detailed structure of the compactor 100, and FIG. 2- (b) shows the process of pressing the tapioca starch into the compactor 100 and discharging it to the tapioca compact .

Referring to FIG. 2, the press 100 includes a press body 110, a transfer screw 120, and an extrusion die 130, so that the tapioca starch is compressed and discharged to the tapioca squeeze.

The presser 100 is provided with a press body 110 formed with a hopper 111 into which a tapioca starch is introduced at one side and a pressing body 110 which is installed inside the press body 110 to be rotated by a motor 121, A conveying screw 120 for conveying the tapioca starch from one side of the main body 110 while being conveyed by the conveying screw 120, And an extrusion die 130 for extruding the extrudate into a rice cake shape.

More specifically, the injection nozzle 112 can be installed inside the compression body 110 in the second step. The injection nozzle 112 receives the primary steam from the outside, reheats the secondary nozzle, 110) while steam is applied to the tapioca starch.

At this time, the injection nozzle 112 is connected to a supply line (not shown) connected to the outer surface of the compression body 110 and is supplied with the primary steam, reheated, and injected into the secondary steam by the additional vaporization.

The reason why the injection nozzle 112 is supplied with the primary steam and reheated and injected into the secondary steam is to spray the steam to the tapioca starch which is fed in one direction through the feed screw 120.

Next, the third step is a step of obtaining a tapioca chip while cutting the tapioca compact to a predetermined size. (S30)

That is, the third step may be carried out or carried out simultaneously with the second step. As shown in Figs. 2- (a) and 2- (b), from the transfer screw 120 of the second step to the extrusion die 130 is rotated at a high speed while rotating the rotary blade 131 disposed at the entrance of the extrusion die 130 to form a tapioca chip by cutting the tapioca chip into a predetermined size.

In the second step, the tapioca squeeze is pushed out from the extrusion die 130 in the same manner as the karoki and discharged. At the same time, the rotary blade 131, which is installed at the entrance of the extrusion die 130 and rotated at high speed, I cut the water to a certain size and make tapioca chips.

Since the cooling path 132 is provided on the outer side of the rotary blade 131, when the tapioca pressed material is cut into a tapioca chip having a predetermined size, the drying process is performed at the same time. It is not necessary to undergo a separate drying process for the payment of the dots.

Next, the fourth step is a step of fuffing the tapioca chip while supplying the tapioca chip to the cylinder 200. (S40)

In other words, the fourth step refers to a step of expanding the tapioca chip in a vacuum state in which a vacuum is drawn into the cylinder 200 without adding water or moisture.

3 is a cylinder 200 according to a preferred embodiment of the present invention. 3, the cylinder 200 in the fourth step includes a cylinder body 210, an inlet 220, a screw 230, a space 240, and an outlet 250 to confirm that the tapioca chip is expanded .

First, the cylinder body 210 is a frame forming the cylinder 200, and a space is provided in which the tapioca chip inserted into the inlet 220 passes from one side to the other side.

At this time, the inside of the cylinder body 210 is preferably kept in a vacuum state by a vacuum pump 211 connected to the cylinder body 210. Moisture remaining in the tapioca chip can be removed because the inside of the cylinder body 210 has a vacuum atmosphere.

Second, the inlet 220 is formed on one side of the cylinder body 210, and a tapioca chip is inserted.

Although the inlet 220 is shown as a hopper shape in FIG. 3, it is not necessarily limited to such a shape, but any shape may be used as long as it is a space into which a tapioca chip can be inserted.

Third, the screw 230 is configured to transfer the tapioca chip, which is formed inside the cylinder body 210 and is rotated by the motor, to be introduced into the inlet 220 while compressing the tapioca chip from one side to the other side.

It is preferable that the screw 230 is rotated at a speed of 120 to 180 rpm per minute. As a result of the experiment, if the rotation speed is less than 120 rpm per minute, the tapioca chips can not be uniformly mixed and transported, and the speed at which the tapioca chip is fed in one direction It was too slow and the productivity was not good.

On the contrary, when the screw 230 rotates more than 180 rpm per minute, the tapioca kneader is piled up at a high speed in the stowage space 240, To 180 rpm (more preferably, at 150 rpm).

Fourthly, the stowage space 240 is formed on the other side of the screw 230 (i.e., the other side of the cylinder body 210), and the tapioca chips transferred from the screw 230 are piled up to form the tapioca paste.

The droplet space 240 is a space in which the mixed tapioca paste is transported by the screw 230 and is prepared to be expanded through the discharge port 250.

In particular, it is preferable that a heating device 241 is installed on the outside of the space 240 to apply heat to the tapioca kneaded product that is accumulated in the space 240. The temperature at this time is preferably 150 to 200 ° C (more preferably, 180 DEG C). In addition, the relief space 240 may provide a pressure of 900 to 950 mPa.

This is because the tapioca chips are constantly conveyed from one side to the other, and the pressure is applied, so that the tapioca kneaded product is present at a pressure of 900 to 950 mPa under the condition of 150 to 200 ° C due to the interaction with the screw 230.

According to the experiments conducted by the inventors of the present invention, it was confirmed that the tapioca dough can not be adequately expanded if the temperature is less than 150 DEG C or less than 900 mPa in the space 240. If the temperature exceeds 200 DEG C or exceeds 950 mPa, the tapioca paste It can be confirmed that there is a possibility that the physical property changes when the water is expanded.

Fifth, the discharge port 250 is formed on the other side of the cylinder body 210, and passes through the stowage space 240, and the tapioca paste is discharged while being fuffed.

That is, the discharge port 250 is closed with a metal stopper 251 so that the inside of the cylinder body 210 is evacuated to prevent the tapioca kneaded product from being discharged. When the tapioca kneaded product is expanded, the metal stopper 251 And opens the discharge port 250. [ Then, when the outlet 250 is opened, the tapioca kneaded product that has been agglomerated in the stowage space 240 is puffed and discharged and cut.

At this time, the tapioca dough is discharged from the discharge port 250 while being expanded to a pressure of 8 to 12 kg / cm 2. This is because when the tapioca paste is bulged at a pressure of less than 8 kg / cm 2, the discharged force is not good and the amount of the tapioca paste that can not be discharged to the outside of the discharge port 250 is large. When the pressure is increased to more than 12 kg / Water is discharged to the discharge port 250 and the spattering rate is not good. Therefore, it is preferable that the tapioca paste is discharged at a pressure of 8 to 12 kg / cm 2 while being expanded.

Finally, the fifth step is a step of pulverizing the expanded tapioca dough and passing it through a screen net. (S50)

That is, the tapioca starch obtained in step 1 has a hard base tissue structure, but when deformed through the second, third, and fourth steps, the base tissue is destroyed and changed into a form having viscoelasticity, This can be applied as an automatic production method.

The tapioca kneaded product discharged through the discharge port 250 of the cylinder 200 is pulverized and passed through a screen mesh having a size of 150 to 200 meshes to collect the finished product in the form of a powder in a cyclone apparatus and pack the product, .

When 2 parts by weight of the finished point settlement is mixed with 100 parts by weight of the molding sand, the elasticity of the mold which has not appeared in the conventional molds appears. This means that the molds are more densely bonded and that the glass moisture moving between the particles of the foundry sand is not easily dried by heat. This prevents the mold from easily drying as well as the defect due to the heat of the mold .

The moisture change of the foundry sand was tested using the completed point settlement through the fifth step. The results are shown in Table 1 below.

A input B input C input moisture(%) Dry water (%) moisture(%) Dry water (%) moisture(%) Dry water (%) Primary 3.04 0.00 3.04 0.00 3.26 3.10 Secondary 2.84 0.20 2.82 0.22 3.10 0.16 Third 2.54 0.30 2.60 0.22 2.96 0.14 A: DEXTRIN (existing point settlement)
B: M-DEX (existing point settlement)
C: Dispensing of the present invention

Namely, Table 1 shows the results of experiment of water change of the foundry sand according to the point settlement. Seven parts by weight of bentonite, 2 parts by weight of sea-coal, 3 parts by weight of water and 2 parts by weight of viscosity- And then examined the moisture change with the pressed specimen.

In the first step, 3 parts by weight of water was added to 100 parts by weight of the shrine and mixed for 1 minute. Then, 7 parts by weight of bentonite, 2 parts by weight of coal powder and 2 parts by weight of a binder were added and mixed for 5 minutes. The changes of moisture were measured by the same method as that of the second step. In the second step, the water was again decomposed and repressed to make the specimen.

According to Table 1, when DEXTRIN is added, the amount of dry water to be evaporated increases to 0.20% and 0.30% as the order is progressed, and when M-DEX is added, It was found that the dry water content was 0.22% and 0.22%, while when the present invention was added, the water content was decreased to 0.16% and 0.14% as the order was progressed. have.

Therefore, it is possible to mix the starch and corn mixture with the purified water mixed with various other additives in order to make the point settlement, the releasing force and the toughness maximized. However, in the present invention, It is expected that the physical properties of the raw materials can be improved more than that of the mixture of starch and corn.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention may be embodied otherwise without departing from the spirit and scope of the invention.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to illustrate them, and the scope of the technical idea of the present invention is not limited by these embodiments.

The scope of protection of the present invention should be construed according to the claims, and all technical ideas within the scope of the claims should be construed as being included in the scope of the present invention.

100: Compressor
110:
111: Hopper
112: injection nozzle
120: Feed screw
121: Motor
130: extrusion die
131: rotating blade
132: cooling furnace
200: Cylinder
210: cylinder body
211: Vacuum pump
220: inlet
230: Screw
231: Motor
240: Racial space
241: Heating device
250: Outlet
251: metal stopper

Claims (6)

Precipitating tapioca powder in a sulfurous acid aqueous solution and separating and precipitating the precipitated tapioca starch;
A second step of drying the obtained tapioca starch and then pressing it while supplying it to a press to obtain a pressed tapioca;
A third step of obtaining a tapioca chip while cutting the tapioca squeeze into a predetermined size; And
And a fourth step of fuffing the tapioca chip while supplying the tapioca chip to the cylinder. The method according to claim 1,
Wherein a spray nozzle is installed in the compression unit of the second step,
The spray nozzle
Wherein the tapioca starch is compressed while being supplied with primary steam from the outside and reheated and sprayed with secondary steam to press the tapioca starch. The method according to claim 1,
Wherein the cylinder of the fourth step comprises:
A cylinder body;
A charging port formed at one side of the cylinder body for charging the tapioca chip;
A screw formed inside the cylinder body and rotated by a motor to compress and transport the tapioca chip from one side to the other side;
A droplet space formed on the other side of the screw to form a tapioca paste with the tapioca chips transferred from the screw being accumulated; And
And a discharge port formed on the other side of the cylinder body and being discharged while being fuffed up while passing through the droplet space. The method of claim 3,
The tapioca paste may contain,
And discharging at a discharge pressure of 8 to 12 kg / cm < 2 > at a discharge port of the tapioca. The method of claim 3,
Following the fourth step,
Further comprising the step of grinding the expanded tapioca paste and passing it through a screen net. In casting use point settlement,
A casting use point payment using tapioca, which is produced by the manufacturing method according to any one of claims 1 to 5.

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