JP2020124788A - Method for manufacturing long-sized heat insulation material - Google Patents

Abstract

To inexpensively manufacture a long-sized heat insulation material from a phenol-based resin foam.SOLUTION: A plate-like phenol-based resin foam laminated plate P pushes and passes through a cutting die 20 having a through hole having a cross-sectional shape of a heat insulation material, and a long-sized heat insulation material having a through hole in section is obtained by a cutting blade. Specifically, the plate-like phenol-based resin foam laminated plate is set on a cavity 11 of a base frame 10 having an U shape in plan view, and a press board 12 is lowered in the cavity to press down the plate-like phenol-based resin foam laminated plate. The phenol-based resin foam laminated plate pushes and passes through a die 20, and is pushed and cut by the cutting blade. The phenol-based resin foam has the most thermally/chemically stable properties among foam plastic foams, and has excellent heat insulation property. The blending is adjusted to obtain a fine bubble structure of less than 100 microns, and push and cutting is smoothly performed without causing deformation.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a method for producing a long heat insulating material by cutting it from a resin foam.

The heat insulating material has a structure in which glass wool or the like is filled between the inner and outer double walls, or foamed plastic such as foamed polyurethane is used as a core material and wall plates (sheets) are arranged inside and outside.
As a method of manufacturing a heat insulating material by the foamed plastic, a cut blade made of a Thomson blade is made along the contours of the recessed portion, the hole portion, and the cutout portion in the foamed plastic serving as the core material, and then the cut portion is formed by a press die. There is one that manufactures a heat insulating material having a required shape by compressing and punching (see Patent Document 1, abstract, FIGS. 1 to 4).

This manufacturing method is excellent in the case of manufacturing a heat insulating wall such as a refrigerator, but the heat insulating material 2 arranged around the high temperature and low temperature pipes 1 shown in FIG. 7 is long and its length is long. It has a hole 2a directed in the direction to the pipe. It is very difficult to manufacture the elongated heat insulating material 2 by the above manufacturing method. This is because it is necessary to form the cut over the entire length in the length direction, and it is difficult to form the cut with the Thomson blade.
Moreover, the heat insulating material 2 shown in FIG. 8 is cut out in the length direction from a rectangular foam plate material (slab material).
For this reason, conventionally, the cutting is performed with a thread-shaped cutting blade (wire saw), and the equipment is large and not general-purpose, and the organization (company) having the equipment is limited. .. Further, due to the cutting resistance applied to the wire, a difference in cross-sectional shape is likely to occur at both ends and the central portion of the shear region, and thus the manufactured product may be warped.

JP 9-196551A

A method for producing a long heat insulating material, which is an alternative to the above-mentioned cutting with a wire saw, has been desired.
An object of the present invention is to provide an inexpensive manufacturing method that replaces the cutting with the wire saw.

In order to achieve the above object, the present invention is to push a resin foam through a die serving as a blade to obtain a heat insulating material made of the resin foam having a required shape.
In the push-cutting by pushing, if the pushing direction is the length direction of the long heat insulating material, the heat insulating material having a required length can be obtained by adjusting the length in the pushing direction. A part of the peripheral edge of the through hole (blade edge) of the die may be opened.

The above-mentioned resin foam is a foamed plastic and is one in which a gas is finely dispersed in a synthetic resin and molded into a foamed (foam) or porous shape. The synthetic resin which is a solid and the gas are non-uniform. Also defined as a distributed system. It is also referred to as plastic foam, cellular plastics, plastic foam, synthetic resin foam, synthetic resin foam, resin foam, spongy plastic, expanded synthetic resin, or the like. If not limited to synthetic resin, it is also called a polymer foam, and one having particularly small bubbles is also called a microcell plastic or a microcell plastic foam.
The “resin foam (resin foam)” in the present invention includes the above foam materials that can be heat insulating materials.

This invention specifically pushes a cross section of a long resin foam through a cutting blade having a through hole of a predetermined shape, and a long heat insulating material having the same cross-sectional shape as the through hole is cut by the cutting blade. It was manufactured.
If a flank is formed on the side of the cutting blade opposite to the through hole, the loss portion of the resin foam to be cut does not collide with the cutting blade, so that the push-cut is smoothly performed.
As the resin foam, the above foam materials may be appropriately adopted, but the type of resin is preferably phenolic. The phenolic resin foam can obtain a long heat insulating material without losing its shape even when pressed.

Here, in the case of producing a long-sized heat insulating material by push-cutting, as a foam, the cross-sectional dimensions of the long-sized heat-insulating material obtained by performing smooth push-cutting should be the same as the shape and dimensions of the cutting blade. It is required that the heat insulating material is not cracked or chipped later, the surface layer does not become a rough surface, and the above two contradictory performances are required. In order to achieve these performances, it is preferred that the phenolic resin foam has a density, a 10% compressive strength and a brittleness within the ranges shown below.
Serial "density 20 kg / ^{m 3} or more and 45 kg / ^{m 3} or less, 10% compressive strength of 10 N / cm ² or more, 30 N / cm ² or less, brittleness is more than 7%, at most 30% phenol Resin Foam"

Further, each of the phenolic resin foams is a phenolic resin foam laminated plate having a face material on the first surface and the second surface, or each of the face materials has gas permeability. You can

In the present invention, since the long heat insulating material is manufactured from the long resin foam by pressing as described above, an inexpensive long heat insulating material can be obtained.

Schematic explanatory drawing of one embodiment of the manufacturing method of the elongate heat insulating material which concerns on this invention Operation diagram of the same embodiment Perspective view of the die (cutting blade) according to the embodiment Plan view of the same die FIG. 4 is a partial cross-sectional view of FIG. 4, where (a) is an AA line, (b) is a BB line, and (c) is a conventional example. Schematic explanatory diagram of each example of pushing out the long insulating material from the long resin foam Omitted perspective view of an example of a long heat insulator Partial perspective view of the same insulation

The phenolic resin foam used in the embodiment according to the present invention has a fine cell structure of less than 100 microns, and the phenolic resin foam has a density of 20 kg/m ³ or more and 45 kg/m ³ or less and 10 % compressive strength of 10 N / cm ² or more and 30 N / cm ² or less, brittleness is more than 7% and satisfy 30% or less.

As described above, the density of the phenolic resin foam is preferably 20 kg/m ³ or more and 45 kg/m ³ or less, more preferably 23 kg/m ³ or more and 35 kg/m ³ or less, and further preferably 26 kg/m ³ As described above, it is 32 kg/m ³ or less.
If the density is lower than 20 kg/m ³ , the bubble film is thin, and the bubble film is easily broken during foaming, making it difficult to obtain a high closed cell structure, and the compressive strength is extremely reduced. Cracks, chips, and roughening of the surface layer are likely to occur. Further, if the density exceeds 45 kg/m ³ and becomes too high, the heat conduction of solids derived from solid components such as resin is increased and the heat insulating performance is deteriorated.
In addition, the said density says the value measured by the method as described in "(1) Foam density" of (Evaluation) mentioned later.

10% compressive strength of the phenol resin foam, as described above 10 N / cm ² or more, preferably 30 N / cm ² or less, more preferably 10 N / cm ² or more and 20 N / cm ² or less.
When the 10% compressive strength is lower than 10 N/cm ² , cracking, chipping, and roughening of the surface layer are likely to occur at the time of pressing. If the 10% compressive strength is higher than 30 N/cm ² , the resistance to push-cutting increases, and it becomes difficult to set the cross-sectional dimension of the long heat insulating material to a predetermined value.
The 10% compressive strength is a value measured by the method described in "(2) 10% compressive strength" of (Evaluation) below.

As described above, the brittleness of the phenolic resin foam is preferably 7% or more and 30% or less, and more preferably 7% or more and 13% or less.
If the brittleness is lower than 7%, that is, if the viscosity is high, it becomes difficult to maintain smooth press-cutting or accuracy of the product dimension after the press-cutting. It is likely to occur and the surface layer is likely to be rough.
The brittleness is a value measured by the method described in "(3) Brittleness" in (Evaluation) described later.

Phenolic resin foam, for example, the continuous discharge of the foamable phenolic resin composition on the running surface material, and the surface of the foamable phenolic resin composition in contact with the surface material It can be obtained by a continuous production method including coating the opposite surface with another surface material, and foaming and heat curing the foamable phenolic resin composition. As another production method, the foamable phenolic resin composition described above is poured into a mold whose inside is coated with a face material or a mold coated with a release agent, and foaming and heat curing. It can also be obtained by a batch production method. The phenolic resin foam obtained by the batch production method can be sliced in the thickness direction and used as necessary.
In this specification, a laminated board in which a phenolic resin foam is laminated on a face material (a laminated board containing a face material and a phenolic resin foam) may be referred to as a phenolic resin foam laminated board. The phenolic resin foam laminate may have one face material, or two face materials (on the first surface (upper surface) and on the second surface of the phenolic resin foam ( It may have face materials (upper surface material and lower surface material) provided on the lower surface). The face material is preferably provided in a form in contact with the phenolic resin foam.

(Evaluation)
(1) Foam density A 20 cm square board is cut out from the phenol resin foam laminate, the face material is removed, and the mass and apparent volume of the phenol resin foam are measured. Using the obtained mass and apparent volume, the density (apparent density) is calculated according to JIS K7222.

(2) 10% compressive strength A test piece with a length of 100 mm and a width of 100 mm is cut out from the phenolic resin foam laminate, and the face material is removed to obtain a test piece. The obtained test piece is aged under an atmosphere of a temperature of 23° C. and a relative humidity of 50% until the difference between the two weighing values performed at intervals of 24 hours becomes 0.1% or less. The 10% compressive strength of the test piece after curing is determined according to JIS K 7220.

(3) Brittleness Brittleness is calculated as follows in accordance with JIS A 9511 (2003) 5.14. Peel off the surface material from the phenolic resin foam laminate, and prepare 12 test pieces cut into a cube of 25 ± 1.5 mm so that one surface includes the surface material. Is measured with an accuracy of ±1%. The test equipment has a door on one side of the box, which can be sealed so that dust does not come out of the box. A shaft is attached to the outside of the center of the 197 mm surface of an oak wooden box with an inside diameter of 191 x 197 x 197 mm , 60±2 rotations per minute. Twenty-four oak dice having a specific gravity of 0.65 and a size of 19±0.8 mm, together with the test piece, were placed in the measuring apparatus and sealed, and then the wooden box was rotated 600±3 times. After the completion of the rotation, the contents of the box are carefully transferred to a mesh having a mesh sieving nominal size of JIS Z 8801 of 9.5 mm, sieved to remove the small pieces, and the remaining test pieces are collected from the net and weighed. Brittleness is calculated by the following formula.
Brittleness (%)=100×(m ₀ −m ₁ )/m ₀
(Where, m ₀ : mass (g) of test piece before test, m ₁ : mass (g) of test piece after test)

1 to 4 with Neomafoam (Asahi Kasei Corporation, registered trademark), which is a plate-shaped phenolic resin foam laminate P having a fine cell structure of less than 100 microns and satisfying each physical property value. With the molding machine A shown, the heat insulating material 2 for the pipe 1 shown in FIG. 8 is manufactured. The values of the density, 10% compressive strength, and brittleness of neomafoam are approximately 27 kg/m ³ , 16 N/cm ² , and 10%, respectively.

The molding machine A provides a U-shaped base frame 10 in a plan view on a frame (not shown), and sets a phenolic resin foam laminate (neoma foam) P in a cavity 11 of the base frame 10. A press board 12 can be moved back and forth in the cavity 11. The press board 12 can be moved up and down by weights, hydraulic cylinders and the like. A die 20, which is a cutting blade for push cutting, is provided on the lower end surface of the base frame 10.

As shown in FIGS. 3 and 4, the die 20 is, for example, one in which each through hole is cut out from a steel plate such as S50C and then hardened, and the Thomson blade is formed on a portion 21 to be a cutting edge with a grindstone. is there. In this embodiment, a cutting edge 21 is provided in a rectangular frame 22, and a pair of left and right arcuate portions (through holes) 21a in the center surrounded by the cutting edge 21 have a cross sectional shape of FIG. Therefore, when passing through the portion 21a, the Thomson blade (cutting blade) 21 around the portion 21a pushes it into the sectional shape.

At this time, at the intersection of the cutting blades 21, as shown in FIG. 5A, the cutting edge 21 of the cutting blade 21 of the loss portion 21b, which is the outer side of the product, is lowered in a curved shape to form a flank 21c. As shown in (b), the cutting edge 21 of the loss portion 21b is lowered by a certain length to form a flank 21c. With this flank 21c, the push-cut is smoothly performed without the phenolic resin foam laminate P of the loss portion 21b colliding with the cutting edge 21 of that portion.
Incidentally, as shown in FIG. 7C, when the heights of both sides are made uniform, the phenol resin foam laminate P of the loss portion 21b collides with the cutting blade 21 of that portion to cut smoothly. There are many cases where it is not possible.

This molding machine A has the above-mentioned configuration. When the plate-shaped phenolic resin foam laminate P is set in the base frame 10 shown in FIG. 1, the press platen 12 is moved down into the cavity 11. The plate-shaped phenolic resin foam laminate P is pushed down with the descending. Then, as shown in FIG. 2, the plate-shaped phenolic resin foam laminate P is pushed through the die 20 and cut by the cutting blade 21. For this reason, the plate-shaped phenolic resin foam laminate P that has passed through the arc-shaped portion 21a becomes the elongated heat insulating material 2 having the arc-shaped cross section shown in FIG.
At this time, since the plate-shaped phenolic resin foam laminated plate P has the above-mentioned composition and has a fine cell structure of less than 100 microns, even if it is pressed out, it does not lose its shape and is smoothly pressed into the shape of FIG. To be done.

The method (arrangement) of the heat insulating material 2 from the plate-shaped phenolic resin foam laminate P is not limited to the die 20 described above, but can be taken effectively, for example, shown in FIGS. 6(a) and 6(b). Various modes such as arrangement are possible.
Further, the heat insulating material of the embodiment is for pipes having an arcuate cross section as shown in FIG. 8, but the present invention can be applied to various kinds of long heat insulating materials as a matter of course.
Further, the phenol-based resin foam laminated plate P is not limited to Neomafoam, and needless to say, the present invention can be applied to the manufacture of long-sized heat insulating materials using various other long-shaped resin foams described above.
As described above, it should be considered that the embodiments disclosed this time are exemplifications in all points and not restrictive. The scope of the present invention is shown by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

A Molding machine P Plate-shaped phenol resin foam laminate (Neomafoam)
1 Piping 2 Piping Heat Insulation Material 10 Base Frame 11 of Molding Machine Cavity of Base Frame 12 Pressing Machine 20 Cutting Die with Cutting Blade (Cutting Blade)
21 Cutting edge (Thomson blade)
21a Arc-shaped part (through hole)
21b loss part 21c flank 22 square frame

Claims (4)

The cross section of the elongated resin foam (P) is pushed through a cutting blade (20) having a through hole (21a) of a predetermined shape, and the cutting blade (20) has the same cross-sectional shape as the through hole (21a). A heat insulating material manufacturing method for manufacturing a long heat insulating material (2). The heat insulating material manufacturing method according to claim 1, wherein a flank (21c) is formed on the opposite side of the through hole (21a) of the cutting blade (21) of the cutting blade (20). The heat insulating material manufacturing method according to claim 1 or 2, wherein the elongated resin foam (P) is made of a phenolic resin foam. The phenolic resin foam has a density of 20 kg / ^{m 3} or more and 45 kg / ^{m 3} or less, 10% compressive strength of 10 N / cm ² or more, 30 N / cm ² or less, brittleness is more than 7%, It is 30% or less, The heat insulating material manufacturing method of Claim 3 characterized by the above-mentioned.

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