KR950005707B1 - Forming method for polystylene foam articles - Google Patents

Abstract

The prefoamed styrene granules were fed into the mold with vacuum and 5-6kg/cm2 compressed air and the gasified water by the compressed air was fed into the mold which was cooled with using of the vacuum. Thus, the compress-transffered prefoamed granules were heated to 70≰C in mold and then the granules were molten-adhered then the gasified water was fed into the mold. The inner parts were dried by vacuum for 20 seconds to obtain the product.

Description

Molding method of Styropol molding

1 is a device diagram illustrating a conventional molding method.

2 is an apparatus diagram illustrating a molding method of the present invention.

The present invention relates to a molding method of a styropol molding, and in particular, the pre-foamed foam particles are rapidly provided to the mold using vacuum and compressed air, and then steam is provided to the mold by vaporizing water with compressed air. The present invention relates to a molding method of a styropole molded article to shorten the whole process.

In general, the styropol moldings are pre-expanded styropol foamed particles in the mold, the steam supply conduit is piped, and then supplied with steam to fuse the styropol foamed particles, and then cooled while leaving the heated mold at a constant temperature, and then cooled The method of separating the mold and then drying the molding is known. In addition, after maintaining the pressure inside the mold at a first vacuum of about 380 mHg, steam is supplied to fuse the styropol pre-expanded particles, and then sprayed with a predetermined amount (hours) of cooling water, and then the pressure inside the mold is again about 450 mm. It is known to make the secondary vacuum state of about Hg so that steam is naturally discharged from the mold into the main vacuum tank. In the former case, since the pressure inside the mold into which the raw material is injected is the same as the atmospheric pressure, steam is permeated between the styropol foam particles only by the pressure of the supplied steam, so the permeation of the steam does not occur quickly and smoothly. Not only does it take a long time, it takes a large amount of steam, and the fusion of the surface layer and the inner layer of the molding becomes uneven, which lowers the quality of the product such as latent force, heat insulation, and thermal insulation. The cooling time of the mold to prevent the mold takes about 20 seconds or more, thus delaying the whole process, and the steam is condensed between the styrofoam foam particles melted during molding to generate condensed water. Not only does it consume a lot of energy, but also productivity O is, in the next repeated step is that the moisture generated in the front-end remaining inside the mold there is a problem such as unfulfilled well smooth re-supply of the raw material.

In the latter case, it is suitable for manufacturing a board-shaped insulation (specific gravity is 25 kg / m 3 or less), and the fusion state is uniform by removing vacuum before and after supplying steam to the mold. Although there is an advantage of reducing the feeding time and the amount of oil, the mold itself is concave and protruded in the manufacture of a mold having a specific gravity value of about 30 kg / m3 (a protective pad inserted into the top, bottom, front and rear to protect the package). It has a variety of shapes, and due to the high specific gravity value of the product, the internal temperature during cooling due to the vacuum is different depending on the thickness difference of the shape of the fusion-molded shape, it is difficult to maintain the uniformity of the product. . For this purpose, a suitable method for the mold has been proposed. For example, as shown in FIG. 1, the filling force from the hopper 10 to the mold 20 is drawn by the compressed air of the raw material feeder 11 No. 4-5 kg / cm 2. Pre-expanded particles (foaming material) is supplied by using, then supplying heated steam (about 110 ℃) to the mold 20 to maintain 90 ℃ suitable for foaming to fusion styropol pre-expanded particles, 50 ℃, about The water of 3 kg / cm 2 water pressure is supplied into the mold 20, 20 'to cool the mold, and then the vacuum is supplied to the mold 20, 20' to complete the tablet for maintaining a predetermined time. .

In Figure 1 (H1) is a raw material valve for controlling the supply of the foam raw material provided to the mold 20 in the hopper 10, (A1) is a compressed air opening and closing valve supplied to the raw material feeder 11, (S1, S2) is a steam valve for opening and closing the heating steam provided to the mold (20), (20 '), (W1, W2) is a water valve for opening and closing the water provided to the mold (20, 20') (V1, V2) is a vacuum valve for opening and closing the vacuum to the mold (20). In general, the temperature of the mold 20, 20 'is 90 ℃ suitable for forming grinding, steam is injected into the mold 20, 20' while maintaining about 110 ℃ the mold 20 ), (20 ') the internal temperature is maintained at about 90 ℃ foam particles are fusion-molded, in this state by supplying cooling water (preferably 50 ℃) to lower the temperature of the mold 20 to 70 ℃ to stop foaming Then, the remaining 90 ° C cooling water in the molds 20 and 20 'is dried by applying a vacuum. However, since this method uses only compressed air through the compressed air valves A1 and A2 when supplying the mold 20 from the hopper 10, it takes a lot of time according to the supply and only cools the mold by water pressure. Since it is supplied into the cooling time was also a disadvantage that takes a lot (more than 20 seconds). The present invention solves this problem, and when the raw material is injected into the mold by using a vacuum and compressed air quickly, after supplying steam, the mold is cooled with water vaporized by compressed air and then vacuumed to shorten the molding time and quality of the product It is characterized in that the uniformity.

That is, in the present invention, in preparing the styropol molded product by injecting the pre-expanded foam particles into the mold, steam supply, vacuum and mold decomposition process, the pre-expanded pre-foamed particles using a vacuum in the raw material input step, and then 5- 6 kg / cm 2 compressed air is transferred to the mold, and after the steam supply is completed, 5-6 kg / cm 2 compressed air is used to supply water into the mold with vaporized water, and then vacuum is provided to the mold. In other words, the phenomenon occurring in the conventional vacuum method (a phenomenon of lowering the vacuum degree and lowering the efficiency of the vacuum pump due to the large amount of water remaining in the mold) is solved.

In the present invention, the step of transferring the pre-expanded particles to the mold to move the pre-expanded particles to a position near the mold from the hopper instantaneously by vacuum and to quickly supply them to the mold by compressed air again, the compressed air is 5- 6kg / cm 2 is preferred, the lower than 5kg / ㎠ the movement efficiency is lower, higher than 6kg / ㎠ there is no difference in movement, but not economical. In this case, of course, a suction force of compressed air of 5-6 kg / cm 2 is simultaneously provided to the mold inlet. When injecting water into the mold in the present invention (water pressure of about 3㎏ / ㎠ is common) It is preferable to give a compressed air of 5-6kg / ㎠ so that the water is injected into the mold in a vaporized state, If it is lower than 5㎏ / ㎠ a bad vaporization state takes a lot of cooling time of the mold, if higher than 6㎏ / ㎠ the cooling time of the mold has the advantage of shortening but economic efficiency is low. Hereinafter, an example of the present invention will be described with reference to the drawings, and the same parts as in the prior art are denoted by the same reference numerals and description thereof will be omitted. Place the pressurized hopper 30 between the hopper 10 and the mold 20, and the hopper compressed air valve (A3) and the hopper vacuum in accordance with the operation of the raw material valve (H1) for controlling the pre-expanded particle transfer of the hopper 10 The valve Vo is configured to open and close selectively, and a shutter, which is a pressurized hopper valve H2, is installed at the outlet of the pressurized hopper 30. A water tank 40 is installed in the cooling transfer path in which the water valves W1 and W2 are installed, and the compressed air of 5-6 kg / cm 2 is provided to the water tank 40.

(W11) and (W21) is an auxiliary valve for controlling the water is supplied to the water tank 40, (T1) and (T2) controls the vaporized water is supplied to the mold 20, 20 'respectively The water tank valve, A4 is a water tank compressed air valve that controls the transfer of compressed air to the water tank (40). In the present invention configured as described above, when the mold 20, 20 'is assembled and pre-foamed raw material particles are injected into the hopper 10, the raw material valve H1 is opened and the hopper vacuum valve Vo is opened at the same time. Particles in the c) are immediately transferred to the pressurized hopper 30. (Of course, a vacuum force is applied to the hopper vacuum valve Vo by the vacuum pump M, and the hopper compressed air valve A3 is closed. The pressurized hopper valve (H2) is also closed.) Then, the raw material valve (H1) and the hopper vacuum valve (Vo) are closed and, on the contrary, the hopper compressed air valve (A3) and the pressurized hopper valve (H2) are opened. The raw material particles are quickly transferred into the molds 20 and 20 '. In this case, as the compressed air valve A1 is supplied together from the raw material input machine 11, the suction force of the raw material particles is increased, and then the compressed air valve A1 pressurized hopper valve H2 and the hopper compressed air valve A3 are closed. Subsequently, the steam valves S1 and S2 are opened to be provided into the molds 20 and 20 ', thereby foaming the raw material particles to fusion molding.

Next, the water tank valves T1 and T2 are opened to make the water mixed with the compressed air in the water tank 40 into a vaporized state to be provided to the molds 20 and 20 '(in the water tank 40). Is filled with a predetermined amount of water and compressed air by the auxiliary water valves W11 and W21 and the water tank compressed air valve A4, and is instantaneously vaporized when the water tank valves T1 and T2 are opened. (20) and (20 ') are preferred, but not particularly limited.) The temperature of molds 20 and 20' is rapidly increased because the volume is increased by vaporization rather than supplying pure cooling water only. It becomes possible to cool, and accordingly, the temperature of the molds 20 and 20 'rapidly becomes 70 degrees C or less, and foaming stops. In other words, it is possible to rapidly lower the temperature of the mold 20, 20 'can shorten the working time and to precisely homogenize the product. Various valve operation control in the present invention is sequentially operated according to the working process, the description thereof will be omitted in the present invention because it uses a conventional technique. According to the present invention, the pressurized hopper 30 is provided to the mold together with the compressed air, so that the filling rate of the edge portion having a thin thickness (for example, 10 mm or less) is made at a strong pressure, so that the defective rate is reduced. It can be advantageously used for water. Thus, the present invention will be described in detail by way of examples, but the present invention is not limited by the examples, and the limited numerical values indicate the numerical values required for producing products of the closest quality according to the examples and comparative examples. will be.

EXAMPLE

1kg of pre-foamed foam particles are put into the hopper and quickly moved to the auxiliary hopper using vacuum, and then transferred to the mold by 5kg / ㎠ compressed air, and at the same time, the mold inlet is separated by 5kg / ㎠ compressed air. The suction force is compressed into the mold, and the mold is heated to 70 deg. Subsequently, a series of steam (110 ° C.) consisting of a preliminary steam, a primary steam, a double-sided steam, and an auxiliary steam was added for about 20 seconds to fuse the expanded particles. Next, 5kg / cm 2 of compressed air was added to 50 ° C. water having a water pressure of 3kg / cm 2, and the vaporized water was provided to the mold. Then, the mold was vacuumed for about 20 seconds to dry and finished. The working time was 69 seconds and about 520 working cycles in 10 hours.

[Comparative Example]

1 kg of the pre-foamed particles are placed in the hopper and provided to the mold through a transfer screw, which is injected with suction force of 5 kg / cm 2 of compressed air at the mold inlet, and the mold is heated to 70 ° C. Subsequently, a series of steam (110 ° C.) consisting of a preliminary steam, a primary steam, a double-sided steam, and an auxiliary steam was added for about 20 seconds to melt molded the foamed particles. Next, water having a temperature of 50 ° C. and a water pressure of 3 kg / cm 2 was supplied into the mold for about 20 seconds, then drained for about 4 seconds, and then dried by adding vacuum for about 20 seconds to complete the manufacture. One working time was 119 seconds. In other words, about 300 working cycles were possible in 10 hours.

As in the comparative examples and examples, the time for filling the foam particles into the mold was greatly shortened from 30 seconds to about 3 seconds, and the time for supplying cooling water was also shortened from 20 seconds to 7 seconds, and the drainage time was 4 In the second or embodiment, it can be seen that the drainage time is not required as the water is sprayed, and the work cycle is also increased from 300 to 520 times to improve productivity.

Claims (1)

Injecting the pre-foamed foam particles into the mold, steam supply, vacuum and the mold decomposition step to produce the styropol moldings, the pre-expanded particles are pre-transmitted by using a vacuum in the raw material input step of 5-6 kg / ㎠ Compressed and transferred to the mold by suction force by compressed air and conveyed compressed air of 5-6㎏ / ㎠, and after the steam supply is completed into the mold, water is vaporized by compressed air of 5-6㎏ / ㎠ and compressed into the mold. Supplying, followed by cooling using a vacuum.