JPH0310470Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) This invention is a socket with an FRP flange for piping used in the hot spring and boiler fields that use high-temperature water, and in the plant industry that handles high-temperature acid and alkaline solutions. This article relates to an FRP flange socket in which the flange socket body made of excellent thermoplastic resin is reinforced with a reinforced plastic layer. (Prior Art) Conventionally, as flanged sockets used for piping in the plant industry field, hot spring field, etc., metal flanged sockets with excellent corrosion resistance have been mainstream. However, these metal flanged sockets have the drawbacks of poor workability and weight, and recently, FRP pipes have begun to be used for piping, making it difficult to connect with conventional metal flanged sockets. The current situation is that there is a strong demand for the development of new flanged sockets. Conventionally, synthetic resin flanged sockets made of heat-resistant vinyl chloride resin are known, but the maximum operating temperature for this is 60°C, and at high temperatures of 100 to 130°C, This product could not withstand use in the plant industry or hot spring field, which requires a high pressure of 10 kg/cm ² . (Purpose of the invention) The present invention was devised in view of the above circumstances, and its purpose is to be a practical product that is resistant to high-temperature acids and alkalis, has high water pressure resistance, and can be used for pipe construction with adhesive. Our objective is to provide a socket with a unique FRP flange. (Structure of the invention) That is, in order to achieve this purpose, the invention
FRP flanged sockets have a reinforced plastic layer made of glass fiber and a thermosetting resin with a low-shrinkage agent added to reduce resin curing shrinkage on the outside of the flanged socket body made of heat-resistant and corrosion-resistant thermoplastic resin. We decided to adopt an integrated structure. (Example) Hereinafter, an example of the present invention will be described with reference to the drawings. The drawing shows an FRP flanged socket A according to an embodiment of the present invention. In the figure, 1 is a flanged socket body made of heat-resistant and corrosion-resistant thermoplastic resin, and in the embodiment, a flanged socket made of heat-resistant vinyl chloride resin is used. This flanged socket made of heat-resistant vinyl chloride resin has a heat resistance of about 60°C, but its water pressure resistance is 7 kg/cm ² or less. 2 is a reinforced plastic layer, which is made by winding glass fiber 3 around the outer periphery of the flanged socket body 1, and injecting a thermosetting resin 4 on top of which a low shrinkage agent is added to reduce the resin curing shrinkage rate. fiber 3
A thermosetting resin 4 is impregnated therein, and the thermosetting resin 4 and the outer circumferential surface of the flanged socket body 1 are integrally fixed to each other to form a desired thickness. Here, a phthalic acid-based unsaturated polyester resin is used as the thermosetting resin 4, and a low shrinkage agent is added to this to reduce the resin curing shrinkage rate.
The reason why the resin curing shrinkage rate has been reduced in this way is that the unsaturated polyester resin layer contracts due to the thermal energy generated as the unsaturated polyester resin constituting the reinforced plastic layer 2 hardens, and this stress is applied to the flange. This is to prevent the flanged socket body 1 from being damaged by acting on the socket body 1. As the low-shrinkage agent, a polyethylene-based low-shrinkage agent is used to suppress the shrinkage of the unsaturated polyester resin by foaming the polyethylene due to the exothermic reaction accompanying the curing of the unsaturated polyester resin. The table below shows the resin curing shrinkage rate when a polyethylene-based low shrinkage agent is added to a phthalic acid-based unsaturated polyester resin. In addition, resin curing shrinkage rate is the percentage decrease in volume when comparing the volume of the resin after curing with the volume of the resin before curing.
This is what is shown. In this table, the blending ratio of the low shrinkage agent is expressed in % by weight.

[Table] According to this table, if 10% of the low shrinkage agent is added, the shrinkage rate will be nearly 50% smaller than when no low shrinkage agent is added, and if 30% of the low shrinkage agent is added, the shrinkage rate will be lower than that of the resin alone. Compared to the shrinkage rate, this is an extremely low 5.9%. Next, as the glass fiber 3, continuous strand mat, glass cloth, glass roving cloth, stretchable glass cloth, etc. can be used. Continuous strand mat with good impregnation properties and stretchable glass cloth (tricot tape: trademark) are used, and depending on the degree of reinforcement, 1 to 5 plies of continuous strand mat are attached. ,
The socket portion 1a is wrapped with stretchable glass cloth (Torikotsutape: trademark). In this embodiment, two plies of continuous strand mat are applied to the flange surface 1b of the flanged socket main body 1 with a nominal diameter of 25 mm, one ply of continuous strand mat is applied to the outer peripheral surface 1c of the flange, and one ply of continuous strand mat is applied to the socket part 1a. One ply of strand mat is attached, and one ply of tricot tape is wound over the continuous strand mat of the socket portion 1a, so that each part forms a continuous glass fiber layer. In addition, the thickness of the reinforced plastic layer 2 can be freely adjusted depending on the size of the flanged socket body 1 and the operating pressure, etc., so that the flange surface 1b and the socket part 1a are thickened to reduce stress. The thickness of the outer peripheral surface 1c of the flange, which only acts, is set to be less than 1/2 of the thickness of the flange surface 1b and the socket portion 1a described above. That is, the reinforced plastic layer 2 on the flange surface 1b and the socket portion 1a, on which stress is strongly applied, is made thick. For example, in the case of a flanged socket body with a nominal diameter of 25 mm, the reinforced plastic layer of the socket portion 1a is
The flange surface 1b was made 5 mm thick, and the flange outer circumferential surface 1c was made 2 mm thick. Performance experiments were conducted, and a water pressure resistance of 10 kg/cm ² was shown in hot water at 100°C. In addition, the FRP flanged socket of each of the above-mentioned examples is made by adding or winding glass fiber onto the flanged socket body made of thermoplastic resin and setting it in a mold, and then applying thermosetting resin to this. Continuous production was carried out using a resin injection molding method that involves injection and curing. (Effects of the invention) As explained above, the FRP flanged socket of the present invention has a flanged socket body made of thermoplastic resin that has heat resistance of around 60°C, and is made of glass fiber and a thermosetting resin with a low curing shrinkage rate. Because it is reinforced with a reinforced plastic layer made of resin, it has heat resistance of over 100℃ and water pressure resistance of over 10Kg/cm ² , making it suitable for use with high-temperature water and high-temperature acid/alkaline solutions. In addition, since the body of the socket with flange is made of thermoplastic resin, it is easy to connect the FRP pipe with adhesive, and since the resin curing shrinkage of the reinforced plastic layer is small, the body of the socket with flange is made of thermoplastic resin. Since no extra stress or strain is applied to the socket, and there is no rust, the durability is superior to conventional metal flanged sockets, and it can be used practically for plant piping for transporting chemicals and hot spring piping for transporting high-temperature water. It is something.

[Brief explanation of the drawing]

The drawing is a partial sectional view showing an FRP flanged socket according to an embodiment of the present invention. A...Socket with FRP flange, 1... Socket body with flange, 2... Reinforced plastic layer, 3... Glass fiber, 4... Thermosetting resin.

Claims (1)

[Scope of utility model registration request] A reinforced plastic layer made of glass fiber and a thermosetting resin that has been added with a low-shrinkage agent to reduce the curing shrinkage rate of the resin is integrally formed on the outside of the flanged socket body made of heat-resistant and corrosion-resistant thermoplastic resin. A socket with an FRP flange.