JPH07108615A - Fiber-reinforced resin tubular body and manufacture thereof - Google Patents

Abstract

PURPOSE:To mold an uncured fiber-reinforced resin layer with a light weight even at the time of requiring high temperature vulcanization and to allow it to endure for a long period by installing the layer formed outside an internal pressure holder disposed outside an inner mold in an inner space of a rubber tube, and bringing the same uncured resin layer into close contact with an inner surface of the tube by expansion pressure of the holder to be cured. CONSTITUTION:An internal pressure holder 3 is disposed inside a rubber tube 5, an inner mold 2 formed with an uncured fiber-reinforced resin layer 4 is installed, and then hydraulic pressure is operated at the holder 3. The pressure is determined to be at least 0.1MPa according to a thickness, a laminated layer structure, laminating angle of a predetermined fiber-reinforced resin tubular body and a material, a thickness of the tube 5 or preferably 0.3MPa or more when an outer mold exists. The holder 3 is expanded by an operation of the pressure thereby to bring the layer 4 into close contact with an inner surface of the tube 5. Then, the layer 4 is cured, the mold 2, the holder 3 and the mold 1 used as required are removed, thereby obtaining a fiber-reinforced resin tubular body integrated with the tube 5 on its surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a tubular body and a roll made of a fiber reinforced resin (hereinafter sometimes referred to as FRP) whose surface is coated with rubber.

[0002]

2. Description of the Related Art FRP has characteristics that it has higher specific strength and higher specific rigidity than metal materials, so that it has been actively used in the industrial field and has been used for rolls. Especially in recent years,
Rolls made of FRP roll tube with rubber lining are also known. This so-called rubber roll is obtained by winding a sheet-shaped unvulcanized rubber around an FRP roll tube and vulcanizing the unvulcanized rubber at a predetermined temperature, pressure and time. If necessary, the outer rubber layer is ground and flattened.

[0003]

In these conventional methods for manufacturing rubber rolls, since heating is performed during vulcanization, there is a problem in the heat resistance of the FRP raw pipe depending on the vulcanization temperature of the rubber material, Since the thermal conductivity is low, there are problems such as difficulty in uniform vulcanization, and the yield as a roll cannot always be said to be high. Further, the FRP roll whose surface is coated with the rubber obtained by these methods is F
There is also a problem that the RP roll tube and the rubber layer are not necessarily sufficiently joined, and they are not sufficiently adapted to the use where higher rotation is desired.

An object of the present invention is to solve the above-mentioned problems, and it is lightweight, can be molded even when high temperature vulcanization is required, has a good yield, can stably withstand long-term use, and is FRP. An object of the present invention is to provide a method for producing an FRP tubular body and a roll whose surface is coated with rubber having a stable and high adhesive strength between a layer and a rubber layer.

[0005]

The present invention comprises the following inventions. 1. A method for producing a fiber-reinforced resin tubular body, which comprises performing the following steps in this order. (1) A step of disposing an internal pressure holder on the outside of the inner mold and forming an uncured fiber-reinforced resin layer on the outside of the internal pressure holder in the inner space of the rubber tube. (2) A step of applying a fluid pressure to the inside of the internal pressure holding body to expand the internal pressure holding body and bringing the uncured fiber-reinforced resin layer into close contact with the inner surface of the rubber tube by the expansion pressure. (3) A step of curing the uncured fiber-reinforced resin layer to obtain a fiber-reinforced resin tubular body covered with a rubber layer. 2. 2. The method for producing a fiber-reinforced resin tubular body according to the above 1, wherein an outer mold having a cylindrical cavity is used. 3. A method for producing a fiber-reinforced resin roll, which comprises adding a step of attaching a shaft to the step of 1 or 2. The present invention will be described in detail below. The method of the present invention is characterized in that the steps as described above are performed in this order, but it may include additional additional steps before and after each step.

In the present invention, the reinforcing fiber used for molding the fiber-reinforced resin layer is preferably a fiber having a high elastic modulus and strength because it is necessary to reduce the amount of bending under load and increase the resonance frequency during rotation. Such fibers primarily include carbon fibers, glass fibers, aramid fibers, and ceramic fibers. Moreover, you may combine these 2 or more types. A fiber having a large specific strength and a high specific rigidity is more preferable because the effect of weight reduction is more remarkable, and a fiber having an elastic modulus of 150 GPa or more, preferably 200 GPa or more is preferable. A carbon fiber is mentioned as a fiber whose elastic modulus is 150 GPa or more.

The matrix resin used for molding the fiber reinforced resin layer is not particularly limited, and includes epoxy resin, unsaturated polyester resin, vinyl ester resin, urethane resin, phenol resin, alkyd resin,
Thermosetting resin such as xylene resin, melamine resin, furan resin, silicone resin, polyethylene resin, polypropylene resin, polyvinyl chloride resin, polymethacrylate resin, ABS resin, fluorine resin, polycarbonate resin,
Polyester resin, polyamide resin (nylon 6,6.
6, 6.10, 6.11, 6.12), a thermoplastic resin such as a polyphenylene sulfide resin, a polysulfone resin, a polyether sulfone resin, a polyether ether ketone resin, and a polyphenylene oxide resin. Of these, epoxy resins, unsaturated polyester resins and vinyl ester resins are preferable from the viewpoint of handleability. Further, two or more kinds of resins and fibers can be combined as required.

The inner die used in the present invention is not particularly limited, but it is preferable to use a die having a cylindrical outer surface, for example, a mandrel made of steel or aluminum.

The internal pressure holder arranged on the outer surface of the inner mold is
It has a function of expanding by applying a fluid pressure to the inside and introducing compressed air or the like. Specifically, cover the tube with a cylindrical inner mold,
Both ends of the tube are brought into close contact with the surface of the inner mold to form a seal when a fluid pressure is applied and a fluid pressure inlet is provided, or a bag having a fluid pressure inlet is used as the inner mold. For example, the inner mold may be arranged so as to wrap the inner mold, but the invention is not limited to this.

The material for the internal pressure holding member is preferably an elastic material, for example, a film made of a thermoplastic synthetic resin such as silicone rubber, natural rubber, polyvinyl chloride, polyamide (nylon), polyester, polypropylene, polyethylene. Alternatively, a film in which these are combined and laminated is exemplified.

Various conventionally known methods can be used to form the uncured fiber-reinforced resin layer on the outside of the internal pressure holding body. For example, the fiber tow of the reinforcing fiber can be impregnated with the uncured matrix resin, and then can be produced according to the method of the present invention described below using a filament winding method. Instead of the filament winding method, it is also possible to use a method of winding a sheet-like prepreg in which the uncured resin is impregnated around the aligned fiber bundles.

The material of the rubber tube used in the present invention includes natural rubber, chloroprene rubber, styrene / butadiene rubber, ethylene / propylene rubber, butyl rubber,
It can be appropriately selected from acrylonitrile-butadiene rubber, silicon rubber, urethane rubber, fluorine rubber, halogenated butyl rubber, chlorosulfonated polyethylene rubber, hydrogenated nitrile rubber and the like.

An outer mold having a cylindrical cavity may be formed on the outside of the rubber tube. As the material of the outer die having the cylindrical cavity, a pipe made of steel, aluminum or fiber reinforced resin is used.

An inner pressure holder is placed inside the rubber tube prepared as described above, and an inner mold having an uncured fiber reinforced resin layer is placed, and then a fluid pressure is applied to the inner pressure holder. . The fluid that acts on the internal pressure holder is not particularly limited, but compressed air is preferable because it is easy to handle. The pressure of the fluid to be applied is not necessarily limited because it depends on the wall thickness of the fiber-reinforced resin tubular body determined in advance by the structural design, the laminated structure, the laminated angle, the material of the rubber tube, the wall thickness, and the presence or absence of the outer mold. But at least 0.1MP
a, if there is an outer mold, it is preferably 0.3 MPa or more.

The uncured fiber-reinforced resin layer is brought into close contact with the inner surface of the rubber tube by expanding the internal pressure holder by the action of fluid pressure. Then, the fiber reinforced resin layer is cured according to a usual method, and the inner mold, the inner pressure holder and the outer mold used as necessary are removed to form a fiber reinforced resin tubular body of the present invention in which a rubber tube is integrated on the surface. Get the body.

In order to improve the adhesiveness between the fiber reinforced resin layer and the rubber tube, a nonwoven fabric may be wound and laminated on the outer layer of the fiber reinforced resin layer to make the surface of the resin excess, or a method may be adopted.

The method for curing the fiber reinforced resin layer is not necessarily limited. It is possible to use a method in which the inner mold and the outer mold are integrated with each other, and the mixture is placed in a heat curing furnace and heated and cured while the fluid pressure is being applied to the inner pressure holder.

In the present invention, the material and structure of the shaft and the bearing portion forming both ends of the fiber reinforced resin roll are not particularly limited. As the material, a metal such as copper or aluminum, and a metal plated on it, or, for applications where weight reduction is particularly desired, made of FRP with carbon fiber or glass fiber as a reinforcing fiber Alternatively, a metal-plated product may be used. F
When the RP bearing portion is molded, the reinforcing fiber and the matrix resin used in the production of the FRP tubular body can be used in combination, but it is not necessarily the same as the material used in the production of the FRP tubular body. It doesn't have to be. In the present invention, the fiber-reinforced resin tubular body and the bearing portion can be joined by a known adhesive.
Alternatively, it is possible to use both mechanical joining such as pinning and adhesive joining. Further, the FRP tubular body and the bearing portion can be integrally formed by the above-mentioned filament winding method or the like.

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

Example 1 As carbon fiber, manufactured by Sumika Hercules Co., Ltd., trade name Magnamite IM6 (tensile modulus 276 GPa, tensile strength 4.
4 GPa) was used. As an uncured thermosetting resin composition, a bisphenol A type epoxy resin (trade name Sumiepoxy ELA128, manufactured by Sumitomo Chemical Co., Ltd.) as an epoxy resin, hexahydrophthalic anhydride (trade name HN5500, Hitachi Chemical Co., Ltd.) as a curing agent (Manufactured by K.K.) and 2,4,6-tris (dimethylaminomethyl) phenol (trade name Sumicure DMP30, manufactured by Sumitomo Chemical Co., Ltd.) as a curing aid in a stoichiometric amount.

A stainless steel mandrel having an outer diameter of 100 mm and a length of 2500 mm is mounted on a filament winding apparatus, a mold release agent is applied to the mandrel, and carbon fiber is impregnated in a liquid epoxy resin composition and sprinkled on the carbon fiber. Then, it was placed in a heat curing furnace and heated at 150 ° C. for 2 hours to be cured. The fiber was wound into a two-layer structure of 3 mm at an angle of ± 55 ° and then 0.5 mm at an angle of 89 °. The obtained FRP tubular body was used as an outer mold. The outer mold is represented by (1) in FIG.

On the other hand, the inner diameter is 45 mm and the length is 2
A 000 mm stainless steel special mandrel (2) is attached to a filament winding apparatus, and a silicon tube (heat-shrink rubber tube ST-350DG manufactured by Shin-Etsu Chemical Co., Ltd.) is covered as the internal pressure holder (3) on the mandrel, and the silicon Both ends of the tube were brought into close contact with the special stainless mandrel to form a seal when air pressure was applied. Then, while impregnating the liquid epoxy resin composition with the carbon fiber, the carbon fiber was wound around the entire outer circumference of the silicon tube. The carbon fiber winding angle was ± 10 °, and the winding thickness was 8.5 mm. The amount of resin adhered was adjusted so that the volume ratio of carbon fiber to resin was 60 ± 2%. In FIG. 1, this uncured fiber-reinforced resin layer is represented by (4).

A silicon tube as the internal pressure holding body (3), an inner mold (2) wound with an uncured fiber reinforced resin layer (4), and a rubber tube (manufactured by Tokai Rubber Industry Co., Ltd., trade name: no cloth) Chemical hose, designated 3 (inch))
(5) and then into the outer mold (1) made of fiber reinforced resin, and into the void formed by the outer surface of the inner mold and the silicon tube through the fluid pressure introduction port (6). By applying an air pressure of 3 MPa for 30 minutes to expand the internal pressure holder, the expansion pressure causes the uncured fiber-reinforced resin layer wound around the inner mold to adhere to the inner surface of the rubber tube and to the inner surface of the outer mold. The uncured fiber reinforced resin layer and the rubber tube were integrated by pressing.

The above-mentioned uncured fiber-reinforced resin layer integrated with the rubber tube is put into a thermosetting oven while air pressure is applied to the outer die, the inner die and the inner pressure holder, while rotating at 120 ° C. for 2 hours. It was heated to cure the fiber reinforced resin. After curing, the mold was removed from the outer mold and the inner mold, and unnecessary parts at both ends were cut and removed to obtain a fiber-reinforced resin tubular body (8) whose surface was covered with rubber.

Example ² A plain woven fabric having a basis weight of carbon fibers of 300 g / m ² was used to give a radius of 30 m.
It is cut into a circle of m, impregnated with the same resin as in the case of the above-mentioned tubular body production, 16 sheets are laminated, and 12 in a hot press.
It was heated and pressed at 0 ° C. and 15 atm for 2 hours to prepare two disks having a thickness of 5 mm. A circular hole having a radius of 10 mm was formed in the center of the disk so that this disk could be used as a bearing (header) of the roll. In addition, the unnecessary resin adhering to the circumferential part of the disk, which sprung up during molding, is removed by cutting, and the radius is accurately 30 mm.
To obtain a bearing made of carbon fiber reinforced resin.

A steel shaft (journal) (9) having a length of 200 mm and a radius of 10 mm was attached to the bearing (7) using a carbon fiber woven cloth and an adhesive. As the adhesive, a mixture of the above-mentioned Sumiepoxy ELA128 with a stoichiometric amount of triethylenetetramine was used, and cured at 80 ° C. for 30 minutes to form a steel shaft (9) and a carbon fiber reinforced resin bearing (7). Joined.

Subsequently, the same adhesive as that used for attaching the shaft to the bearing is applied to the peripheral portion of the disk of the bearing (7) to which the steel shaft (9) is attached, and the above fiber is applied. Fit both ends of the reinforced resin tubular body and
It was cured for 0 minutes and adhered. Then, the outer surface was ground by a grinder to correct the dynamic balance. In this way, a carbon fiber reinforced resin roll having the steel shaft (9) attached and the surface covered with the rubber (5) was obtained. This could be suitably used as a transport roll.

[0028]

The method of the present invention makes it possible to use a rubber material that is lightweight and requires high temperature vulcanization, has a good yield, and can secure a stable and high adhesive strength between the FRP layer and the rubber layer, which is stable for long-term use. It is possible to manufacture FRP roll shells and rolls coated with rubber that withstands static electricity. Further, this method has high productivity and is economically advantageous. The FRP roll coated with rubber obtained by the method of the present invention is
It contributes to improvement of productivity and labor saving in various industrial fields such as film transportation, paper manufacturing, and printing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an arrangement of an inner mold, an outer mold, an inner pressure holder, a rubber tube, and an uncured fiber-reinforced resin layer, which shows a molding state of a fiber-reinforced resin tubular body having rubber on its surface.

FIG. 2 is a partial cross-sectional view of an example of a fiber reinforced resin roll manufactured by using the method of the present invention.

[Explanation of symbols]

 1: Outer mold 2: Inner mold 3: Inner pressure holder 4: Unhardened fiber reinforced resin layer 5: Rubber tube 6: Fluid pressure inlet 7: Bearing 8: Fiber reinforced resin tubular body 9: Shaft

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Claims (3)

[Claims] 1. A method for producing a fiber-reinforced resin tubular body, which comprises performing the following steps in this order. 1. A step of disposing an internal pressure holder on the outside of the inner mold and forming an uncured fiber reinforced resin layer on the outside of the internal pressure holder in the inner space of the rubber tube. 2. A step of applying a fluid pressure to the inside of the internal pressure holder to expand the internal pressure holder, and the expansion pressure causes the uncured fiber-reinforced resin layer to adhere to the inner surface of the rubber tube. 3. A step of curing the uncured fiber-reinforced resin layer to obtain a fiber-reinforced resin tubular body covered with a rubber layer. 2. The method for producing a fiber-reinforced resin tubular body according to claim 1, wherein an outer mold having a cylindrical cavity is used. 3. A method for producing a fiber-reinforced resin roll, which comprises adding a step of attaching a shaft to the step of claim 1 or 2.