KR101192398B1 - Open sand mold for expanded polypropylene a buoy and manufacturing method which uses this - Google Patents

Abstract

PURPOSE: An open-type mold for an EPP float and a manufacturing method using the same are provided to extend the service life of a float by preventing the hydrolysis of the flat through the corrosion resistance of the float. CONSTITUTION: An open-type mold(1) for an EPP float comprises a steam supplying unit(7) supported by an upper die(2). The steam supplying unit comprises guide pipes(72), a cylinder(73), a steam supplying pipe, and a steam supplying hole. The guide pipes are stood outside of an upper inner mold. A steam supply port(71) is formed on the top portion of the guide pipe. The cylinder is installed in the upper portion of the guide pipe. The steam supplying pipe is moved downward into a cavity between the upper inner mold and a lower inner mold(32). The steam supplying hole is formed in the front end of the steam supplying pipe and supplies steam to a cavity.

Description

Open mold for expanded polypropylene and the manufacturing method using the same {open sand mold for expanded polypropylene a buoy and manufacturing method which uses this}

The present invention relates to a medium-large foamed polypropylene rich and an open mold used for molding the rich and the method for producing a rich using the same, and more specifically without using a chemical blowing agent Expanded Polypropylene (Expanded Polypropylene, EPP) is a foamed polypropylene (Expanded Polypropylene, EPP) to develop a high-density product of 200mm or more that is not possible conventionally developed by the present inventors (10-2012-0009947) of the open mold for expanded polypropylene products The present invention further provides an open mold for foamed polypropylene rich and a method for producing rich using the same, which fills a hole formed by a steam supply pipe in a molding process.

Expanded polypropylene (EPP), an eco-friendly material that can be recycled, is widely used as a cushioning interior material in the automobile industry.

However, in the case of expanded polypropylene, the moldability at 100 mm or more is deteriorated compared to the excellent buoyancy and utility, and most of the foam polypropylenes have been applied to thin plates or single parts of 100 mm or less.

Products using foamed polypropylene include multilayer polypropylene resin foamed molded articles of Korean Patent Publication No. 10-0686505 (2007.02.23.), A manufacturing method thereof, and a container made of multilayered polypropylene resin foamed molded article, vehicle impact It is applied only to products having a relatively thick thickness of 100 mm or less, such as a cushioning material and a member for a vehicle, and a packaging box made of micro foamed polypropylene sheet of Korea Registered Utility Model Publication (Y1) 20-0319656 (2003.07.16.).

This is combined by using high temperature and high pressure steam in the state of physically foamed polypropylene. When the thickness of the product is 200mm or more, the surface is formed correctly, but the inside is not bonded because the steam pressure does not reach. The durability of the external force is reduced, and there is a disadvantage in that the product is easily damaged by the external force. The buoyancy, such as styrofoam, is provided. In a limited situation, there is a demand in the industry for a mold apparatus having a novel configuration that can solve such problems.

In order to solve the above-mentioned problems, the present inventors put a variable mold elastically supported by a spring on the edge of the cavity of the lower mold in which the steam supply hole constitutes an open mold for the expanded polypropylene product formed on the cavity surface. To increase the supply of sufficient expanded polypropylene particles, and to protrude a steam supply pipe formed with a steam supply hole to approach the center inside the cavity to smoothly supply the steam to the inside of a product thicker than 200 mm. The patent application (10-2012-0009947) was developed by developing an open mold for a foamed polypropylene product.

When using the above-described open mold for expanded polypropylene products, it is possible to produce products that are thicker than 200 mm, which was not possible to be molded in the past, so that the rich and the like can be manufactured in aquaculture farms. It is expected to prolong the life of the rich because it provides corrosion resistance that does not decompose, and it is possible to minimize the environmental pollution since it is possible to recycle the entire amount after recovery.

However, according to the above prior art, there is a problem in that the filling operation is performed separately by cutting and inserting a rod made to a suitable length into a hole formed by separating the steam supply pipe from the product.

KR 100686505 B1 2007.02.23. KR 200319656 Y1 2003.07.16.

Therefore, the present inventors have studied and developed the present invention in order to improve the problems of the open-type mold for foaming polypropylene products which have been applied for. In the present invention, the present invention is a foamed polypropylene (Expanded Polypropylene, EPP) which is physically foamed without using a chemical blowing agent. The process of forming a hole formed by a steam supply pipe by further improving the configuration of an open mold for expanded polypropylene products developed and filed by the present inventor (10-2012-0009947) to produce a thick rich product of 200 mm or more, which is impossible in the related art. The present invention has been completed with technical problems in providing an open mold for polypropylene rich foam and a rich manufacturing method using the same.

In order to solve the problem, the present invention includes upper and lower molds having upper and lower molds each of which a cavity is formed to form a steam supply space inside the upper and lower mold bodies, and the upper and lower molds have steam supply holes. Forming to provide a vapor pressure into the cavity, the upper mold is provided with a raw material feeder to inject the raw material into the cavity, the lower inner edge of the mold for forming an open mold for the foam polypropylene rich with a variable mold;

Installing a steam supply means to be supported on the upper mold;

The steam supply means is erected from the upper inner mold to the upper mold outer side, and the upper pipe and the lower inner mold by the cylinder in the state in which the guide tube is piped to the upper side, the cylinder is installed in the upper portion of the guide tube, It includes a steam supply pipe installed to descend into the cavity formed between the;

The front end of the steam supply pipe was provided with an open mold for foamed polypropylene rich which formed a steam supply hole for supplying steam to the cavity and a method of manufacturing foamed polypropylene rich using the same.

When using an open mold for foam polypropylene rich provided by the present invention and a rich manufacturing method using the same, it is possible to produce foam polypropylene rich with a diameter of 200 mm or more that was not conventionally molded.

In addition, when the rich polypropylene foam is produced, it is expected to prolong the life of the rich because it provides corrosion resistance that does not hydrolyze even when exposed to sea water for a long time, and can minimize the environmental pollution since the entire amount can be recycled after recovery.

Figure 1 is a perspective view of a preferred embodiment of the open mold for the present invention polypropylene foam
Figure 2 is an enlarged perspective view of an important part of the open mold for polypropylene foam of the present invention
3 is a side cross-sectional view of the open mold for polypropylene foam according to the present invention, in which a steam supply pipe is inserted into a cavity in a state in which a variable mold is raised;
Figure 4 is a side cross-sectional view of the open mold for polypropylene foam of the present invention a state in which the steam supply pipe of the steam supply means moved to the outside of the cavity in the state in which the variable mold is raised
Figure 5 is a side cross-sectional view of the open mold for polypropylene foam of the present invention is a state in which the variable mold is pressed in the state in which the steam supply pipe of the steam supply means moved to the outside of the cavity
Figure 6 is an enlarged cross-sectional view for showing the operating state of the variable mold applied to the present invention
7 is a process block diagram for preparing the foamed polypropylene rich provided by the present invention
Figure 8 is a perspective view of aquaculture farms made by using an open mold for expanded polypropylene rich applied to the present invention
9 is a cross-sectional view of FIG.

Open mold for expanded polypropylene (Expanded Polypropylene, EPP) provided by the present invention and the rich manufacturing method using the same to compensate for the disadvantages of molding the product to the conventional 100mm or less to enable the molding of the rich 200 ~ 3000mm diameter It will be described below with reference to the accompanying drawings, the foamed polypropylene rich and the production method thereof provided by the present invention.

1 is a perspective view showing a preferred embodiment of the open mold for polypropylene foam according to the present invention, Figure 2 is an enlarged perspective view of an important part of the open mold for polypropylene foam for the present invention, Figures 3, 4, 5 Shows a cross-sectional side view and the like of the open mold for polypropylene foam according to the present invention.

The open mold 1 for polypropylene foam provided by the present invention is composed of an upper mold 2 and a lower mold 3 as shown in the drawing, and an open mold having a variable mold 4 installed on the lower mold 3 side. .

The upper mold (2) and the lower mold (3) have upper upper mold (22) and lower inner mold (32) so as to form steam supply spaces (23, 33) inside the upper mold body (21) and the lower mold body (31), respectively. Install.

The upper inner mold 22 and the lower inner mold 32 form a cavity 5 which is a concave empty space, and a vapor supply hole 6 is formed to penetrate into the cavity 5. The number of the cavities 5 is determined according to the size of the mold 1, and the present invention shows an example in which six cavities 5 are applied.

The upper mold 2 is provided with a raw material injector 9 for feeding raw materials (foamed polypropylene particles) into the cavity 5 so that the raw materials can be introduced into the cavity 5.

Steam is supplied to the steam supply spaces 23 and 33 through a steam supply line (not shown), which is connected to the upper mold 2 and the lower mold 3, and the supplied steam is 180 to 190 ° C and 6 to It is supplied under the pressure condition of 9 kgf / cm 2, and is supplied into the cavity 5 through the steam supply holes 6 formed in the upper inner mold 22 and the lower inner mold 32. At this time, the supplied vapor pressure may be molded into a 200mm product.

The present invention is intended to be able to mold a sphere having a diameter of 200 mm or more, which was conventionally considered impossible.

To this end, the present invention has actively developed two parts, the first is the variable mold (4) configuration, the second is to provide a steam pressure near the center of the product steam supply means (7) to ensure the smooth formability ) Is installed.

The variable mold 4 is installed at the edge of the lower mold 32, as shown in Figures 3 to 6, the configuration of which forms an upper open chamber 41 on the outside of the lower mold 32, The variable mold 4 is installed in the chamber 41 so as to be elastically supported by the spring 42, and the variable width is deformed in various ways according to the size of the product, preferably in the range of 20 to 60 mm.

The variable mold 4 is formed in a band shape. The lower side of the variable mold 4 has a guide pin 43 formed with a protrusion 44 passing through the bottom of the chamber 41 and being caught outside the chamber 41. Assembly so that the variable mold 4 can be safely operated without separation.

In the variable mold 4 configured as described above, when the polypropylene particles are injected into the mold 1, the variable mold 4 moved upward by the elastic force of the spring 42 is the upper mold 22 as shown in FIGS. 3 to 4. In order to maintain the grounded state and mold the product, the upper inner mold 22 presses the variable mold 4 when pressing the upper mold 2 toward the lower mold 3 as shown in FIG. 4) is molded into the chamber 41 is made.

In the present invention, as a means for providing a vapor pressure to the vicinity of the center of the rich (10) in the present invention, the steam supply means 7 is provided to be supported by the upper mold (2) (or lower mold (3)).

The steam supply means 7 is erected out of the upper mold (2) from the upper inner mold (22) and the guide tube 72, the steam supply port 71 is piped to the upper side and the upper portion of the guide tube (72) The cylinder 73 is installed so as to descend into the cavity 5 formed between the upper inner mold 22 and the lower inner mold 32 by the cylinder 73 in the state in which the guide tube 72 is inserted. It includes a steam supply pipe (74).

At the tip of the steam supply pipe 74, a steam supply hole 75 for supplying steam toward the cavity 5, such as the upper inner mold 22 and the lower inner mold 32, is formed.

The steam supply holes 6 and 75 formed in the upper inner mold 22, the lower inner mold 32, and the steam supply pipe 74 allow a gap narrower than the diameter of the polypropylene particles to be formed. 75) to prevent the loss of polypropylene particles.

In the case of forming the steam supply pipe 74 as described above, the steam is supplied to the vicinity of the center of the rich 10 having a diameter of 200 mm or more through the steam supply hole 75 formed in the steam supply pipe 74 to obtain polypropylene particles. It will be able to melt.

Although the present invention shows an example in which the steam supply means 7 is installed on the upper mold 2, it is obvious that the steam supply means 7 may be installed on the lower mold 3 or the upper mold 2 or the lower mold 3 together.

In the figure, reference numeral 8 denotes a mill pin used to take out a product, and a steam supply hole may be formed in the mill pin as needed.

Open mold (1) for the expanded polypropylene rich of the present invention configured as described above can be used when manufacturing the expanded polypropylene rich (10) mainly having a diameter of 200mm or more, the following describes the production method of the present invention do.

Method for producing the expanded polypropylene rich 10 provided in the present invention is physical foam, primary material input, primary molding, steam supply pipe extraction, secondary material input, secondary molding and cooling, as shown in FIG. It is made by the process of taking out and drying, and each process is demonstrated concretely below.

1) physical foaming

In the physical foaming, the expanded polypropylene particles are added to a closed foaming tank and heated at a temperature of 40 to 60 ° C. for 12 hours to foam the expanded polypropylene particles in a desired state.

It is not foamed below 40 ℃, it is possible to foam above 60 ℃ but economic loss due to the large heat loss.

2) primary material input

The primary mold 2 is first brought into close contact with the variable mold 4 while the variable mold 4 is moved upward, and the polypropylene particles are physically foamed by heating at a temperature of 40 to 60 ° C. for 12 hours in a foam tank. The feeder 9 feeds into the cavity 5.

Open mold (1) for the expanded polypropylene rich used in the present invention is to produce the rich (10) having a diameter of 200mm ~ 3000mm as described in detail above to the steam supply pipe 74 near the center of the cavity (5) The vapor supply pipe 74 is formed inside, and a fine steam supply hole 75 is formed like the inner surface of the cavity 5.

This steam supply pipe 74 is for providing a vapor pressure to the vicinity of the center of the cavity (5).

3) primary molding

In the state of injecting the expanded polypropylene particles having the physical foam into the open mold 1 for the expanded polypropylene rich, the steam is supplied at a temperature of 180 to 190 ° C. to the steam supply pipe 74 inserted into the vicinity of the center of the cavity 5.

At this time, the primary molding is performed only in the vicinity of the center of the cavity 5 to which steam is supplied among the expanded polypropylene particles having physical foaming filled in the cavity 5.

4) Withdrawal of steam supply pipe

As described above, the steam supply pipe 74 is drawn out of the cavity 5 while the primary molding is performed.

5) Secondary material input

As described above, when the steam supply pipe 74 is taken out to the outside of the cavity 5, a space corresponding to the volume of the steam supply pipe 74 is formed, and the expanded polypropylene particles are additionally introduced through the raw material feeder 9.

6) Secondary Forming and Cooling

In the state in which the expanded polypropylene particles are injected as described above, steam is supplied through the steam supply hole 6 formed in the upper inner mold 22 and the lower inner mold 32 and pressurized at the same time.

At this time, the steam (5) is supplied into the cavity 5 and the mold is pressurized by the width of the variable mold (4) for 400 to 500 seconds at a pressure of 6 ~ 9kgf / ㎠, in the process of foaming made physical foam The surface of the polypropylene particles melts and bonds with neighboring particles.

After molding as described above, the rich molded by water cooling is cooled.

7) outtake

The mold is opened to take out the finished rich man 10.

8) Drying

Since the expanded polypropylene rich 10 provided in the present invention is configured to form a product using vapor pressure, it contains a considerable amount of moisture therein.

Such a water content state causes a weight increase and a buoyancy decrease in the future, it must be removed.

Common foamed polypropylene products are 100mm or less products, but water is evaporated naturally without a separate drying process. However, in the case of the rich 10 provided in the present invention, products having a diameter of 200mm or more are evaporated without artificial drying. You can't.

Therefore, in the present invention, the molded rich 10 is put in a drying chamber maintaining a dry state of 80 ℃ to be dried for 40 hours.

When the drying process is performed, moisture remaining deep inside the rich 10 is gradually discharged to the outside through fine pores between the expanded polypropylene particles.

In the case of the foamed polypropylene rich 10 shown in FIG. 8 manufactured and configured as described above, corrosion resistance that is not hydrolyzed even after prolonged exposure to seawater is provided and can provide excellent shock absorption and restoring force as an independent bubble structure. You can use it for a long time.

In addition, it is an eco-friendly material that is physically foamed without using a chemical foaming agent, so that it can be recycled entirely after recovery, and it is light like Styrofoam while maintaining high mechanical strength, elastic modulus and flexibility, thereby improving the functionality of the ball.

In the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the protection scope of the present invention should not be limited to the described embodiments, but should be defined by equivalents as well as the following claims.

1: (opening type for polypropylene foam) mold 2: upper mold
21: upper body 22: upper inner model
23,33: Steam supply space 3: Lower type
31: lower body 32: lower body
4: variable mold 41: chamber
42: Spring 43: Guide pin
44: Stone 5: cavity
6: Steam supply hole 7: Steam supply means
71: steam supply port 72: guide pipe
73: cylinder 74: steam supply pipe
75: steam supply hole 9: raw material feeder
10: foam polypropylene rich
110: Hole

Claims (2)

An upper mold 2 provided with an upper inner mold 22 and a lower inner mold 32 having a cavity 5 formed therein so that the steam supply spaces 23 and 33 are formed inside the upper mold body 21 and the lower mold body 31. ) And the lower mold (3), the upper inner mold 22 and the lower mold (32) to form a steam supply hole (6) to provide a vapor pressure into the cavity (5), the upper mold (2) In the construction of the open mold (1) for the foamed polypropylene rich in which the raw material feeder is installed to feed the raw material into the cavity (5), and the variable mold (4) is provided at the edge of the lower inner mold (32).
Install the steam supply means (7) to be supported by the upper mold (2),
The steam supply means (7) is installed in the upper portion of the guide tube 72 and the upper side of the upper mold (22) and the upper side of the upper mold (2) and the steam supply port 71 piped to the upper side, Steam supply pipe installed so as to descend into the interior of the cavity 5 formed between the upper inner mold 22 and the lower inner mold 32 by the cylinder 73 in the state in which the cylinder 73 and the guide tube 72 are inserted. Including 74,
An open mold for expanded polypropylene rich parts, characterized in that a steam supply hole (75) for supplying steam to the cavity (5) is formed at the tip of the steam supply pipe (74).
A physical foaming step of foaming the particles by injecting the expanded polypropylene particles into a closed foaming tank and heating them at a temperature of 40 to 60 ° C. for 12 hours;
A raw material input step of injecting polypropylene particles having been physically foamed into the cavity of the open mold;
A primary forming step of forming a mold only in the vicinity of the cavity by supplying steam at a temperature of 180 to 190 ° C. to a steam supply pipe inserted into the vicinity of the cavity in the state in which particles having physical foaming are introduced;
A steam supply pipe extraction step of drawing the steam supply pipe out of the cavity in a state where primary molding is performed;
A secondary material input process of additionally adding expanded polypropylene particles equal to the volume of the steam supply pipe while the steam supply pipe is blown out of the cavity;
In the state in which the expanded polypropylene particles were put in the secondary state, at the same time as the pressing force, the steam pressure supplied through the steam supply hole formed at a predetermined interval on the inner surface of the mold was provided to melt the surface of the particles, followed by secondary molding, followed by water cooling. A secondary forming and cooling process of cooling the rich
A take-out step of taking out the rich man by opening the mold;
Method for producing expanded polypropylene rich, characterized in that for 48 hours after drying in a drying chamber to maintain a dry condition of 80 degrees after taking out from the mold.

Images