KR102344955B1 - Mold apparatus for manufacturing specimen and method for manufacturing specimen using the same - Google Patents

Abstract

Disclosed are a mold device for manufacturing a specimen of a fiber composite used in the manufacture of a pressure vessel comprising: an upper plate pressing a wound fiber composite downward; a lower plate pressing the wound fiber composite upward; and an intermediate plate interposed between the upper plate and the lower plate and winding the fiber composite, and a method for manufacturing a specimen using the same.

Description

Mold apparatus for specimen manufacturing and specimen manufacturing method using the same

To a mold apparatus for manufacturing a specimen and a method for manufacturing a specimen using the same, and more particularly, a mold apparatus for manufacturing a specimen for evaluation of physical properties (eg, tensile strength, compressive strength, shear strength, etc.) of a fiber composite used in manufacturing a pressure vessel And it relates to a method for manufacturing a specimen using the same.

A pressure vessel for storing high-pressure gas requires a material having a strong and high-pressure resistance, and in particular, in order to improve fuel efficiency and performance of a vehicle, it is essential to reduce the weight of the structure. The application of light and strong carbon fiber composites is one of the most effective ways to replace metal pressure vessels.

Composite material pressure vessels are typically fabricated through a filament winding process. The filament winding process has the advantage of being able to easily manufacture a structure having a cylindrical shape or a curvature by integral molding, and maximizing the performance of a composite material by intensively reinforcing fibers in the load transfer direction. The filament winding process is a composite molding method for manufacturing a rotationally symmetrical structure by winding a continuous fiber impregnated with a resin on a rotating mandrel of a cylindrical shape and curing it.

An object of the present invention is to provide a mold apparatus for manufacturing a specimen capable of evaluating physical properties such as tensile strength, compressive strength, and shear strength.

Another object of the present invention is to provide a method of manufacturing a specimen capable of evaluating physical properties, such as tensile strength, compressive strength, and shear strength, using the mold apparatus.

1. According to one aspect, a mold apparatus for manufacturing a specimen of a fiber composite material used in manufacturing a pressure vessel is provided. The mold device includes an upper plate for pressing the wound fiber composite downward; a lower plate for pressing the wound fiber composite upward; and an intermediate plate interposed between the upper plate and the lower plate, on which the fiber composite material is wound. may include

2. In the first embodiment, a guide groove for cutting a specimen extending in one direction may be provided on at least one side of the upper surface of the intermediate plate.

3. In the first or second embodiment, a groove may be formed on one side of the intermediate plate.

4. In any one of the first to third embodiments, the intermediate plate may include a body portion and an edge portion at both sides of the body portion, and the edge portion may be detachable from the body portion.

5. In the fourth embodiment, a groove may be formed on one side of the edge portion.

6. In any one of the first to fifth embodiments, a spacer may be inserted into the intermediate plate to increase the thickness of the intermediate plate.

7. In any one of the first to sixth embodiments, the upper plate, the middle plate, and the lower plate may have through-holes penetrating them, and can be screwed through the through-holes.

8. In any one of the first to seventh embodiments, the fiber composite material may be wet wound on the intermediate plate.

9. According to another aspect, a method of making a specimen is provided. The specimen manufacturing method uses the mold device of any one of the first to eighth embodiments, and winds the fiber composite material impregnated with the fiber on an intermediate plate, and the fiber composite material wound on the upper and lower portions of the intermediate plate. disposing an upper plate for pressing downward and a lower plate for pressing upwardly pressing the wound fiber composite material, and curing the resin; may include steps.

The present invention has the effect of providing a mold apparatus for manufacturing a specimen capable of evaluating physical properties such as tensile strength, compressive strength, shear strength, and a method for manufacturing a specimen using the same.

1 is a schematic diagram of a mold apparatus for manufacturing a specimen according to an embodiment of the present invention.
Figure 2 (a) is a schematic view of an intermediate plate according to an embodiment of the present invention, Figure 2 (b) is a cross-sectional view taken along line II' of Figure 2 (a).
Figure 3 (a) is a schematic view of an intermediate plate according to another embodiment of the present invention, Figure 3 (b) is an enlarged view of the groove.
4 is a schematic diagram of an intermediate plate according to another embodiment of the present invention.
5 is a photograph of manufacturing a specimen according to an embodiment of the present invention.

In the present specification, the singular expression includes the plural expression unless the context clearly dictates otherwise.

Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

When the positional relationship of two parts is described with ‘on’, ‘on’, ‘on’, ‘beside’, etc., between the two parts unless ‘directly’ or ‘directly’ is used. One or more other parts may be located in

In describing the drawings, positional relationships such as 'top', 'top', 'bottom', 'bottom' etc. are only described based on the drawings, and do not represent absolute positional relationships. That is, the positions of 'upper' and 'lower' or 'upper surface' and 'lower surface' may be changed according to the observed position.

In this specification, terms such as include or have means that the features or components described in the specification exist, and the possibility that one or more other features or components will be added is not excluded in advance.

In interpreting the components, it is construed as including an error range even if there is no separate explicit description.

In the present specification, "to" in "a to b" representing a numerical range is defined as ≥ a and ≤ b.

In this specification, the term 'plate' means that at least a portion includes a flat section.

In general, a specimen for measuring the physical properties of a fiber composite to which a filament winding process is applied is manufactured in a cylindrical shape (ring shape). Accordingly, there is a problem in that it is impossible to evaluate physical properties such as tensile strength, compressive strength, and shear strength of the fiber composite material.

As a result of repeated intensive research to solve the above-described problems, the present inventors include: an upper plate for pressing the wound fiber composite downward; a lower plate for pressing the wound fiber composite upward; and an intermediate plate interposed between the upper plate and the lower plate, on which the fiber composite material is wound. By manufacturing a specimen using a mold device including The present invention was completed.

1 schematically shows a mold apparatus for manufacturing a specimen (hereinafter also referred to as a 'mold apparatus') according to an embodiment of the present invention. Hereinafter, the present invention will be described in more detail with reference to the drawings.

Referring to FIG. 1 , a mold apparatus for manufacturing a specimen according to an embodiment of the present invention may include an upper plate 10 , an intermediate plate 20 , and a lower plate 30 .

The upper plate 10 and the lower plate 30 are disposed on the upper and lower portions of the intermediate plate 20 on which the fiber composite material is wound, so that the upper plate 10 presses the wound fiber composite material downward, and the lower plate 30 ) can press the wound fiber composite upwards. In this case, it may be advantageous to remove excess resin and pores that may be present in the wound fiber composite. In addition, during thermosetting of the resin, it is possible to prevent the resin having a lowered viscosity according to an increase in temperature from escaping to the outside. As a pressing method, for example, there is a method of applying a predetermined pressure by fastening the upper plate 10, the intermediate plate 20 and the lower plate 30 wound with the fiber composite material with a screw 40, but is limited thereto. no.

The size, shape, material, etc. of the upper plate 10 and the lower plate 30 are not particularly limited, and the roles of the upper plate 10 and the lower plate 30, the size, shape, and material of the middle plate 20, A person skilled in the art may appropriately select the fiber composite material specimen to be manufactured in consideration of the size, type, and the like. For example, when it is necessary to apply a predetermined pressure to the wound fiber composite material through the screw 40 fastening of the upper plate 10, the intermediate plate 20 and the lower plate 30 on which the fiber composite material is wound, the intermediate plate It may be necessary to thicken the thickness of the upper plate 10 and the lower plate 30 in proportion to the width of 20 .

A fiber composite material may be wound on the intermediate plate 20 . Since the intermediate plate 20 includes a flat section, a fiber composite specimen having a flat area can be manufactured using the intermediate plate 20 . Therefore, it is possible to evaluate the physical properties of the fiber composite material, such as tensile strength, compressive strength, and shear strength, using the specimen, and as a result, it is possible to more easily conduct research on the fiber composite material by dataizing them.

According to one embodiment, the winding of the fiber composite material may be performed by rotating the intermediate plate 20 . For example, winding of the fiber composite may be performed by mounting the intermediate plate 20 to a mandrel and rotating the mandrel.

According to one embodiment, the intermediate plate 20 may be wet wound with a fiber composite material. Wet winding may mean winding the fiber after impregnating it by passing it through a resin bath. In this case, the types of fibers and resins used are not particularly limited, and fibers and resins commonly used in the field of manufacturing a high-pressure vessel may be used without limitation. For example, carbon fiber and/or glass fiber may be used as the resin, and an epoxy resin may be used as the resin. On the other hand, the resin bath may further include a curing agent, a curing accelerator, a heat stabilizer, a UV stabilizer, an antioxidant, a flame retardant, a lubricant, an impact modifier, a dispersant, an antioxidant, etc. have.

According to one embodiment, a guide groove 22 for cutting a specimen extending in one direction may be formed on at least one side of the upper surface (and/or lower surface) of the intermediate plate 20 (see FIG. 2 ). Thereby, the fiber composite specimen can be cut more easily.

According to one embodiment, one or more grooves 23 may be formed in at least one side surface of the intermediate plate 20 (see FIG. 3 ). Accordingly, it is possible to suppress the occurrence of slip as a result of the increase of the winding angle and/or the use of a low-viscosity resin when winding the fiber composite, and as a result, a fiber composite to which various winding angles are applied and/or a resin having various viscosities is applied. Specimens can be easily prepared. Here, at least one side on which the groove 23 is formed means a side on which the fiber composite material is wound and in direct contact with the fiber composite material.

According to one embodiment, the width W of the groove 23 may be set to 0.5 to 1.5 times the width of the fiber spreading. In this case, the effect of suppressing the occurrence of slip during winding of the fiber composite material may be more excellent. Here, the 'fiber spread width' means that, in general, fibers for fiber composite materials such as carbon fiber and glass fiber have a bundle shape made of a plurality of filaments, and the filaments are spread by winding tension during winding to have a predetermined width. However, it may mean the width at this time. For example, the width W of the groove 23 may be 0.6 to 1.4 times, for example, 0.7 to 1.3 times, for another example, 0.8 to 1.2 times of the fiber unfolding width, but is limited thereto. it is not For example, when the fiber unfolding width of 24K carbon fiber made of 24,000 filaments is 5 mm, the width W of the groove 23 may be set to 5 mm ± 1 mm.

According to one embodiment, the depth (L) of the groove 23 may be appropriately selected by those skilled in the art in consideration of the diameter, number, fiber spread width, and the number of winding stacks of the fiber composite material of the filaments constituting the fiber. For example, as the number of stacked windings increases, the depth L of the groove 23 can be increased.

According to one embodiment, the intermediate plate 20 includes the body portion 20a and the edge portions 20b on both sides of the body portion 20a, and the edge portion 20b may be detachable from the body portion 20a. (See Fig. 4). Accordingly, the intermediate plate 20 of various shapes can be easily formed by replacing the edge portion 20b. For example, after the edge portion 20b without the groove 23 and the edge portions 20b including the grooves 23 of various sizes on one side are provided, the properties of the fiber or resin to be wound, the winding bending angle Various shapes of the intermediate plate 20 can be formed by selecting the edge portion 20b without the groove 23 or the edge portion 20b including the appropriate groove 23 and attaching it to the body portion 20a according to the like. have. According to one embodiment, the body portion 20a and the edge portion 20b may be fittedly coupled. For example, a fitting groove 20aa is formed in the body portion 20a, and a fitting protrusion 20bb is formed in the edge portion 20b, so that the body portion 20a and the edge portion 20b are detachably attached. However, the coupling method of the body portion 20a and the edge portion 20b is not limited thereto.

According to one embodiment, the thickness of the intermediate plate 20 may be controlled by inserting a spacer (not shown). For example, a spacer is disposed above or below the intermediate plate 20 , or a plurality of intermediate plates 20 are present and a spacer is inserted between the plurality of intermediate plates 20 to increase the thickness of the intermediate plate 20 . could be thicker. The size, shape, and material of the spacer may be appropriately selected by a person skilled in the art in consideration of the size, shape, and material of the intermediate plate 20 . For example, the spacer may have the same size, shape, material, etc. as that of the intermediate plate 20, or may have a size, shape, material, etc. that are easy to fit into the intermediate plate 20, but is limited thereto. no.

The fastening structure of the upper plate 10 , the middle plate 20 and the lower plate 30 is not particularly limited, and a person skilled in the art can determine the size and shape of the upper plate 10 , the middle plate 20 and the lower plate 30 . , can be appropriately selected in consideration of the material and the like. For example, the upper plate 10, the middle plate 20, and the lower plate 30 are provided with through-holes 11, 21, 31 through which they can pass, and the through-holes 11, 21, and 31 are formed. The upper plate 10 , the middle plate 20 and the lower plate 30 may be fastened with screws 40 , but the present invention is not limited thereto. At this time, the number, position, and screw 40 fastening method of the through-holes 11, 21, 31, etc. can be determined by a person skilled in the art in consideration of the size, thickness, material, winding position, etc. of each plate 10, 20, 30. can be appropriately selected.

The mold apparatus according to one embodiment of the present invention described above may be useful for manufacturing a plate-shaped fiber composite specimen to which a filament winding process is applied, and as a result, it may be easy to evaluate physical properties such as tensile strength, compressive strength, and shear strength.

According to another aspect, a method of making a specimen is provided. In the method, a fiber composite material impregnated with a fiber is wound on an intermediate plate, an upper plate pressing the fiber composite wound on the upper and lower portions of the intermediate plate downward, and a lower plate pressing the wound fiber composite material upward disposing, and curing the resin.

First, the fiber composite material impregnated with the resin may be wound on the intermediate plate. At this time, the winding may be performed with a predetermined winding angle under a predetermined tension, and an intermediate plate having no groove or an appropriate groove size may be selected and used according to the characteristics of fibers and resins, the winding bending angle, and the like.

Thereafter, the upper plate and the lower plate may be disposed on the upper and lower portions of the intermediate plate on which the fiber composite is wound. In this case, the upper plate, the middle plate, and the lower plate are screwed through the through-holes passing through the plates to be integrated and apply a predetermined pressure to the wound fiber composite material.

Thereafter, the resin may be cured. For example, curing may be thermosetting, so that the integrated top plate, middle plate and bottom plate can be put into an oven. Curing conditions, for example, curing temperature, time, etc. can be appropriately selected by a person skilled in the art according to the type and content of fibers and resins used, the presence or absence of a curing catalyst, type, content, and the like.

According to one embodiment, the method for manufacturing the specimen may further include separating the cured fiber composite material from the mold device. The separation may be performed by removing the upper plate and the lower plate, and cutting the cured fiber composite material. At this time, if the intermediate plate is provided with a guide groove for cutting, the cured fiber composite material can be more easily cut using the guide groove.

5 is a photograph showing a method of manufacturing a specimen according to an embodiment of the present invention. Referring to FIG. 5 , an intermediate plate is prepared (S1), and a fiber composite is wound on the intermediate plate to prepare an intermediate plate in which the fiber composite is wound (S2), and the upper and lower portions of the intermediate plate on which the fiber composite is wound After arranging the upper plate and the lower plate on (S3), the resin is cured by putting it in an oven (S4), and taking it out (S5) to prepare a specimen having a flat area.

The specimen manufactured by the manufacturing method according to an embodiment of the present invention may have a flat area, and as a result, the evaluation of physical properties such as tensile strength, compressive strength, and shear strength of the fiber composite material can be easily performed through the specimen. .

Up to now, the present invention has been looked at focusing on examples. Those of ordinary skill in the art to which the present invention pertains will understand that the present invention can be implemented in modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments are to be considered in an illustrative rather than a restrictive sense. The scope of the present invention is indicated in the claims rather than the foregoing description, and all differences within the scope equivalent thereto should be construed as being included in the present invention.

Claims (9)

A mold device for manufacturing a specimen of a fiber composite material used in manufacturing a pressure vessel, the mold device comprising:
an upper plate for pressing the wound fiber composite downward;
a lower plate for pressing the wound fiber composite upward; and
an intermediate plate interposed between the upper plate and the lower plate, on which the fiber composite is wound; includes,
The intermediate plate includes a body portion and edge portions on both sides of the body portion,
The edge portion is detachable from the body portion
Mold apparatus for making specimens.
The method of claim 1,
A mold apparatus for manufacturing a specimen provided with a guide groove for specimen cutting extending in one direction on one side of the upper surface of the intermediate plate.
The method of claim 1,
A mold apparatus for manufacturing a specimen in which a groove is formed on one side of the intermediate plate.
delete The method of claim 1,
A mold apparatus for manufacturing a specimen in which a groove is formed on one side of the edge part.
The method of claim 1,
A spacer is inserted into the intermediate plate so that the thickness of the intermediate plate becomes thicker.
The method of claim 1,
The upper plate, the intermediate plate, and the lower plate are provided with a through hole through which they can pass, and the mold apparatus for manufacturing a specimen that can be screwed through the through hole.
The method of claim 1,
A mold apparatus for manufacturing a specimen in which the fiber composite material is wet-wound on the intermediate plate.
A method for manufacturing a specimen using the mold apparatus of any one of claims 1 to 3 and 5 to 8, the method comprising:
winding the fiber composite material in which the fibers are impregnated with the resin on the intermediate plate;
disposing an upper plate for pressing the wound fiber composite downward and a lower plate for pressing the wound fiber composite upward on the upper and lower portions of the intermediate plate; and
curing the resin; A method for preparing a specimen comprising the steps of:

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