TWI832914B - Butterfly valve and body, fluid contacting member and disk used in the same and method of manufacturing the disk - Google Patents

Abstract

A butterfly valve which may enhance corrosion resistance or acid resistance with keeping its strength, have light weight and realize mass production, and method of manufacturing the same are disclosed. The butterfly valve comprises a body in which an inserting space is formed and a disk inserted into the inserting space of the body, wherein fluid flow is opened or closed in response to rotation of the disk. Here, the disk includes a disk body formed of a metal, and at least one plastic layer formed on the disk body.

Description

Butterfly valve, its body part, fluid contact part and disc, and How to make a disc

The present invention relates to a butterfly valve and a manufacturing method thereof.

Existing butterfly valves are constructed solely of steel and are therefore strong but prone to corrosion, heavy and expensive to manufacture. In particular, the butterfly valve requires precision machining, but since the butterfly valve is made of steel, it is difficult to precisely process it and thus is difficult to mass-produce.

An object of the present invention is to provide a butterfly valve that maintains strength while improving corrosion resistance or acid resistance, is lightweight, and can be mass-produced, and a manufacturing method thereof.

In order to achieve the above object, a butterfly valve according to an embodiment of the present invention includes a body part formed with an insertion space; and a disc inserted into the insertion space of the body part, and the disc rotates to open and close the fluid. flow. The disc includes a disc body made of metal; a first plastic layer formed on the disc body and made of a first plastic; and formed on the first plastic layer. A second plastic layer on one plastic layer and made of a second plastic. Wherein, the melting point of the first plastic is higher than the melting point of the second plastic.

A disc for a butterfly valve according to an embodiment of the present invention includes a disc body made of metal; a first plastic layer formed on the disc body and made of a first plastic; and formed on the disc body. A second plastic layer is formed on the first plastic layer and is made of a second plastic. The first plastic and the second plastic have different melting points.

In the butterfly valve according to one embodiment of the present invention, the body portion surrounding the disk includes an upper body and a lower body, and an insertion space is formed when the upper body and the lower body are combined. The disk is inserted into the insertion space, and at least one of the upper body and the lower body includes a metal frame and a plastic layer formed on the frame.

In one embodiment of the present invention, the fluid contact part in contact with the fluid includes a body made of metal and requiring mechanical processing; a first plastic layer formed on the body and made of a first plastic; and formed on the body. A second plastic layer on the first plastic layer and made of a second plastic. Wherein, the plastic layer is formed by molding, and the first plastic and the second plastic have different melting points.

A method of manufacturing a disc for a butterfly valve according to one embodiment of the present invention includes the step of forming a first plastic layer on a disc body made of metal by molding; and forming a first plastic layer on the first plastic layer. The step of forming the second plastic layer by molding. Wherein, the first plastic as the material of the first plastic layer and the second plastic as the material of the second plastic layer have different melting points.

According to the butterfly valve and its manufacturing method of the present invention, a disc having a disc body made of metal and a plastic layer molded on the disc body is used. Therefore, it can not only keep close to the butterfly valve which is made only of steel. The strength of the shaped valve and the ability to improve corrosion resistance or acid resistance.

In addition, the butterfly valve is lightweight and easy to mold, so it can be mass-produced. Moreover, the butterfly valve can be precisely manufactured.

100: disc

100a: Opening and closing part

100b: Operation Department

100c: Fixed part

102: Disc support part

102a: first support part

102b: Second support part

104:Ontology

104a: Upper body

104b: Lower body

200,202,310,510,512,540,542:hole

204:Opening part

208:Space

209,520,550: slot

220,222:Screw

230a, 232a, 234a, 236a: screw insertion part

240,242,246: Locking parts

300: disc body

300a:Skeleton structure

302: First plastic layer

304: Second plastic layer

500:Upper frame

504:Head

502: Containment Department

506: Pipe joint

508a,508b: bottom

530:Lower frame

532: Containment Department

534: Pipe joint

536a,536b: bottom

560:Upper plastic layer

Figure 1 illustrates a perspective view of the structure of a butterfly valve according to an embodiment of the present invention; Figure 2 illustrates an exploded structure of a butterfly valve according to an embodiment of the present invention; Figures 3A to 3C illustrate an embodiment of the present invention. The disc of the embodiment; Figures 4A and 4B show a partial cross-section of the disc of one embodiment of the invention; Figures 5A and 5B show the upper body and the lower body of one embodiment of the invention; and Figure 6 A disc body according to another embodiment of the present invention is shown.

The singular expressions used in this specification also include plural expressions unless otherwise expressly stated in the specification. In this specification, terms such as "constituting" or "comprising" should not be understood to mean that they must include all the constituent elements or steps described in the specification, but should be understood to mean that some of the constituent elements or steps may not be included, or that some of the constituent elements or steps may not be included. Other components or steps may also be included. In addition, terms such as "... part" and "module" described in the specification represent a unit that handles at least one function or action, which can be implemented by hardware or software, or by a combination of hardware and software.

The present invention relates to valves, and in particular to butterfly valves. Compared with butterfly valves made only of metal such as steel, the present invention not only maintains strength and precision, but also improves service life, corrosion resistance, etc., and can significantly reduce manufacturing costs. Moreover, productivity is significantly improved and mass production is possible.

Existing butterfly valves are only made of steel and therefore have high strength but are difficult to precisely process, so productivity is very low and manufacturing costs are high. Furthermore, when butterfly valves are used in ships, water treatment equipment (desalination equipment, sewage treatment equipment), etc., they are prone to corrosion and have a lifespan of less than one year.

On the other hand, the butterfly valve of the present invention improves corrosion resistance and lifespan (can be used for more than ten years) by molding plastic on metal (such as steel or light metal such as aluminum), reduces manufacturing costs, and significantly reduces weight.

Obviously, these techniques described below are not limited to butterfly valves and can be applied to a variety of valves.

Various embodiments of the present invention are described in detail below with reference to the accompanying drawings.

Figure 1 illustrates a perspective view of the structure of a butterfly valve according to an embodiment of the present invention. Figure 2 illustrates an exploded structure of a butterfly valve according to an embodiment of the present invention. Figures 3A to 3C illustrate an embodiment of the present invention. The disc of the embodiment, Figures 4A and 4B show a partial cross-section of the disc of one embodiment of the present invention, Figures 5A and 5B show the upper body and the lower body of one embodiment of the present invention, Figure 6 shows a disc body according to another embodiment of the present invention.

Please refer to Figure 1. The butterfly valve in this embodiment includes a disc 100, a disc support part 102 and a body 104. In some embodiments, the butterfly valve may only include the disc 100 and the body 104 without including the disc support 102 .

As described below, the disc 100 can be made of plastic by two consecutive moldings on metal (such as steel or light metal such as aluminum) to perform the opening and closing action of fluid flow. The disc 100 is opened when the fluid is allowed to pass (for example, rotated 90 degrees), and the disc 100 is closed when the fluid is cut off as shown in Figure 1 .

The disc support 102 plays a role in stably supporting the disc 100, and may be made of, for example, polytetrafluoroethylene (PTFE), perfluoro alkyl (Perfluoro alkyl, PFA) or polyvinylidene fluoride (PVDF). ) and other fluororesin. Fluorine resin is a general term for resins containing fluorine in the molecule. It has excellent heat resistance, chemical resistance, electrical insulation, small friction coefficient, and no adhesion or adhesiveness.

The body 104 surrounds the disc support 102, for example, by adding polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphtalamide (Polyphtalamide), PPA), polyamide (Polyamide, PA6), polyamide (Polyamide, PA66), polyketone (Polyketone, POK) or polyethylene (Polyethylene, PE) mixed with glass fiber (Glass fiber). When the main body 104 is manufactured in this way, the strength, impact resistance, mechanical properties, etc. of the main body 104 can be improved. The resulting effects will be described in detail later.

According to another embodiment, the body 104 can be made of, for example, polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6), It is made of polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber and carbon fiber. When the main body 104 is manufactured in this way, the strength, impact resistance, mechanical properties, etc. of the main body 104 can be improved.

According to yet another embodiment, the body 104 may be made of, for example, polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6), Polyamide (P A66), polyketone (POK) or polyethylene (PE) mixed with glass fiber, carbon fiber and graphite. When the main body 104 is manufactured in this way, the strength, impact resistance, mechanical properties, etc. of the main body 104 can be improved.

The specific structure and combination relationship of the constituent elements of the butterfly valve of the present invention will be described below.

Referring to Figures 2 to 5B, the disk 100 may include an opening and closing part 100a, an operating part 100b and a fixing part 100c.

The opening and closing part 100a is a member that opens and closes the flow of fluid, and may have a circular shape, for example. The structure of the opening and closing part 100a will be described later.

The operating part 100b is coupled to the upper end of the opening and closing part 100a and protrudes upward. This operation part 100b penetrates the hole 510 formed in the center part of the upper body 104a, and protrudes upward toward the upper side of the upper body 104a as shown in FIG. 1 . This operating part 100b is combined with a control part (not shown) and rotates according to the control of the control part. As a result, the opening and closing portion 100a rotates to perform opening and closing operations.

The fixing part 100c is inserted into the hole 540 formed in the center part of the lower body 104b, so that the disk 100 can be stably fixed to the body 100. The fixing part 100c does not protrude to the outside when inserted, and may have a shorter length than the operating part 100b.

The disk support part 102 may include a first support part 102a and a second support part 102b.

The first support portion 102a has the same shape as the opening and closing portion 100a, for example, a circular shape, and may have a larger size than the opening and closing portion 100a.

According to one embodiment, the first support part 102a is formed with a space (hole) 208 penetrating the front and back, and a groove 209 may be formed around the entire periphery of the upper end of the first support part 102a.

According to one embodiment, a hole 200 for the operation part 100b to be inserted is formed at the upper center part of the first support part 102a, and a hole 202 for the fixing part 100c to be inserted is formed at the lower end center part.

The second support part 102b may also have the same shape as the opening and closing part 100a, such as a circular shape. An opening 204 may be formed at the upper end center part, and an opening may be formed at the lower end center part. The opening part 204 and the opening part may be formed separately. There are holes. The hole in the opening 204 corresponds to the hole 200 formed in the upper end of the first support part 102a, and the hole formed in the opening in the center of the lower end may correspond to the hole 202 formed in the lower end of the first support part 102a.

According to one embodiment, the second supporting part 102b may be made of ethylene propylene diene monomer (EPDM), fluorine rubber (Fluoro Elastomers, FKM), silicone, or the like.

In this structure, the opening and closing part 100a of the disk 100 is inserted into the space 208 of the first support part 102a, and the second support part 102b is lockable to the groove 209 formed in the upper end of the first support part 102a. That is, the second support part 102b applies pressure to the opening and closing part 100a of the disk 100 inserted into the space 208 of the first support part 102a so that the opening and closing part 100a is stably fixed.

According to one embodiment, the size of the opening and closing portion 100a of the disk 100 is slightly larger than the space 208 of the first support portion 102a. The outermost outline of the opening and closing portion 100a is made of plastic and is elastic, so it can be inserted into the opening and closing portion 100a. space 208 of the first supporting portion 102a.

In this structure, the operation part 100b is exposed to the outside through the hole 510 formed in the upper center part of the upper body 104a, and the fixing part 100c can be inserted into the hole 540 formed in the lower center part of the lower body 104b.

At this time, the operating part 100b is firmly fixed to the supporting parts 102a and 102b and the upper body 104a through the locking members 242 and 246, and the fixing part 100c can be firmly fixed to the lower body 104b through the locking member 240.

However, the structure in which the disc 100 is rotated to fix, open and close is not limited to the above structure, and can be modified in various ways.

Referring to Figures 5A and 5B, the upper body 104a may include an upper base made of metal (such as steel or light metal such as aluminum) and an upper base made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide ( The upper plastic layer 560 is formed of PPS), polyphthalamide (PPA), polyamide (PA6), polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber.

The upper base may include an upper frame 500, a receiving part 502, a head 504, a plurality of pipe coupling parts 506, and bottoms 508a and 508b on both sides.

The upper frame 500 is a frame. For example, both the upper end and the lower end may have a semicircular shape, and may be made of metal (especially light metal). The upper frame 500 and the lower frame 530 may form a space into which the disc supporting part 102 of the supporting disc 100 can be inserted. In order to stably fix the disk support part 102, a groove 520 may be formed on the lower outer surface of the upper frame 500, and a groove 550 may be formed on the inner surface of the lower frame 530.

In the central portion of the upper frame 500, the receiving portion 502 may extend in a direction intersecting the upper frame 500, preferably in a vertical direction, and may be made of metal.

A hole 510 is formed in the receiving part 502, and the operating part 100b of the disc 100 can be exposed to the outside through the hole 510.

The head 504 is connected to the end of the receiving part 502 and is made of metal, and may have a larger size than the receiving part 502 . Wherein, the operating part 100b can protrude onto the head 504.

The pipe joint 506 is used to connect pipes, and may be, for example, ribs protruding from the upper frame 500 , and may be made of metal.

According to one embodiment, holes 512 may be formed on the pipe coupling part 506. After arranging pipes on both sides of the butterfly valve, fixing components such as bolts are passed through the pipes and the butterfly valve is locked to combine the butterfly valve with the pipes. At this time, the bolt can penetrate the pipe connecting portion 506 of the butterfly valve. That is, the pipe coupling part 506 is used to couple the butterfly valve and the pipe.

The bottoms 508a and 508b are respectively formed at two ends of the upper frame 500, can be used to be combined with the lower body 104b, and can be made of metal. For example, screw insertion portions 230a and 232a may be formed on each of the bottom portions 508a and 508b.

The upper plastic layer 560 is formed on the upper base, for example, through insert molding.

According to one embodiment, the upper plastic layer 560 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6), Made of polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber.

According to another embodiment, the upper plastic layer 560 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6) , polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber and carbon fiber, or glass fiber, carbon fiber and graphite.

According to another embodiment, the upper plastic layer 560 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6) , polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with carbon fiber or carbon fiber and graphite. As a result, the strength, impact resistance, and mechanical properties of the upper base can be improved.

That is, the upper frame 500 made of steel of the upper base can be formed to a very thin thickness, and by mixing the glass fiber or the like in the upper plastic layer 560, it is possible to maintain a structure similar to that of the upper base made only of steel. Overall strength. As a result, the weight of the upper base can be reduced while maintaining strength.

The lower body 104b will be described below with reference to Figures 5A and 5B. The lower body 104b may include a lower base and a lower plastic layer 562. The lower base may include a lower frame 530, a receiving part 532, a pipe connecting part 534, and bottoms 536a and 536b.

The lower frame 530 may have a shape corresponding to the upper frame 500 , such as a semicircular shape, and may be made of metal, such as light metal such as steel or aluminum.

The accommodating part 532 is a part that accommodates the fixing part 100c of the disk 100, has a hole 540 into which the fixing part 100c can be inserted, and may be made of metal.

The pipe coupling part 534 has the same function as the pipe coupling part 506. For example, it may protrude from the lower frame 530 and may be made of metal. Holes 542 may be formed on the pipe joint 534 .

The bottoms 536a and 536b are respectively formed at two ends of the lower frame 530, can be used to be combined with the upper body 104a, and can be made of metal. For example, screw insertion portions 234a and 236a may be formed in each of the bottom portions 536a and 368b. The upper body 104a and the lower body 104b can be combined by inserting the screws (bolts) 220 and 222 (as shown in Figure 2) into the screw insertion portions 230a, 232a, 234a and 236a.

The lower plastic layer 562 is formed on the lower base, for example, by insert molding.

According to one embodiment, the lower plastic layer 562 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6), Made of polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber.

According to another embodiment, the lower plastic layer 562 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6) , polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber and carbon fiber, or glass fiber, carbon fiber and graphite.

According to another embodiment, the lower plastic layer 562 can be made of polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), polyamide (PA6) , polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with carbon fiber, or carbon fiber and graphite.

As a result, the strength, impact resistance, and mechanical properties of the upper base can be improved.

That is, although the lower base uses a thin lower frame 530 made of steel, the overall strength of the lower base can be maintained similar to that of a lower base made of steel by mixing the glass fiber or the like into the lower plastic layer 562 . As a result, the weight of the lower base can be reduced while maintaining strength.

The structure of the disk 100 will be described in detail below.

Referring to Figures 3A to 4B, the opening and closing part 100a of the disk 100 may include a disk body 300, a first plastic layer 302 and a second plastic layer 304. The figures only show that two plastic layers 302 and 304 are formed, but the opening and closing part 100a may include more than three plastic layers.

The disc body 300 is the basic skeleton of the disc 100 and may be made of metal (for example, light metal such as steel or aluminum).

According to one embodiment, the disc body 300 may have a circular shape as shown in FIGS. 3A to 3C and may be formed with at least one hole 310 . In addition, the disk body 300 is not limited to the structure of FIG. 3 , and may have a skeleton structure 300 a with a circular shape and a lot of space inside as shown in FIG. 6 .

The first plastic layer 302 can be formed on the disc body 300 through molding. At this time, the first plastic layer 302 can cover the entire disk body 300 .

According to one embodiment, the first plastic layer 302 may be made of high-strength plastic, such as engineering plastic or super engineering plastic. For example, the first plastic layer 302 can be composed of a polyphenylene ether resin composition composed of polyphenylene ether resin and polystyrene resin, or polyimide (POLYIMIDE), polystyrene (POLYSULFONE), or poly(phenylene ether) resin. POLY PHENYLENE SULFIDE, POLYAMIDE IMIDE, POLYACRYLATE, POLYETHER SULFONE, POLYETHER ETHER KETONE, POLYETHER IMIDE ), liquid crystal polyester (LIQUID CRYSTAL POLYESTER), polyetherketone (POLYETHER KETONE), etc. and their compositions.

The second plastic layer 304 can be formed on the first plastic layer 302 by molding. At this time, the second plastic layer 304 can cover the entire first plastic layer 302 and can fill the holes formed on the disc body 300 and the first plastic layer 302 .

According to one embodiment, the second plastic layer 304 may be composed of fluororesin, such as polytetrafluoroethylene (PTFE), perfluoro alkyl resin (Perfluoro alkyl, PFA) or polyvinylidene fluoride (PVDF), etc. .

According to another embodiment, the second plastic layer 304 may be composed of plastic with a lower melting point than the first plastic layer 302 . For example, the second plastic layer 304 may be composed of polytetrafluoroethylene (PTFE).

The first plastic layer 302 and the second plastic layer 304 may be made of plastics with different melting points.

According to one embodiment, the corrosion resistance or acid resistance properties of the second plastic constituting the second plastic layer 304 are better than the corrosion resistance or acid resistance properties of the first plastic constituting the first plastic layer 302 , and the first plastic The strength properties of the plastic are better than those of the second plastic. That is, the first plastic can function to enhance the strength of the disc 100 , and the second plastic can function to prevent corrosion or oxidation due to fluid.

In summary, the opening and closing portion 100a of the disc 100 can be composed of the disc body 300, the first plastic layer 302 and the second plastic layer 304 formed in sequence.

Existing discs are made of steel and thus machined. However, it is difficult to precisely process steel into the required shape when manufacturing this kind of machinery, so the productivity of the discs is significantly reduced. Therefore, mass production is difficult to achieve. Of course, since the discs are made of steel, although they are strong, they are heavy and costly to manufacture, and are prone to corrosion.

On the other hand, in the disc 100 of the present invention, only the disc body 300 as the basic skeleton is made of metal, and the plastic layers 302 and 304 are formed on the disc body 300 through two molding processes.

The disc body 300 is significantly thinner than the existing disc, so even if it is mechanically processed, it can be easily processed into a desired shape accurately. In particular, since the precise shape of the disc 100 can be achieved through the first plastic layer 302, there is no need to precisely process the disc body 300. Therefore, mass production can be achieved.

Furthermore, the plastic layers 302 and 304 can significantly improve the corrosion resistance and acid resistance of the disc 100 and make the strength characteristics better. Specifically, since the first plastic layer 302 is composed of It is made of engineering plastic or super engineering plastic, so the disc 100 can not only have a strength similar to that of existing discs but also be ultra-lightweight. For example, assuming that a conventional butterfly valve made only of steel weighs 1 kg, the butterfly valve of the present invention can have a weight of approximately 350 g while maintaining similar strength. That is, ultra-lightweight can be achieved.

In addition, the first plastic layer 302 can be omitted and the second plastic layer 304 made of polytetrafluoroethylene (PTFE) is directly formed on the disc body 300 made of steel. However, in this case, it is possible to form the second plastic layer 304 on the metal. The thickness of polytetrafluoroethylene (PTFE) is not necessarily an issue. That is, a precise disk shape cannot be produced.

Therefore, the valve manufacturing method of the present invention uses high-strength plastic (for example, engineering plastic or super engineering plastic) that can be manufactured into precise shapes on metal. That is, the valve manufacturing method can achieve a precise shape by forming the first plastic layer 302 made of high-strength plastic on the disc body 300 made of metal.

Afterwards, the valve manufacturing method may form a second plastic layer 304 made of polytetrafluoroethylene (PTFE) on the first plastic layer 302 made of high-strength plastic. Wherein, the polytetrafluoroethylene (PTFE) can be formed on the high-strength plastic to a predetermined thickness.

In short, the opening and closing portion 100a of the disc 100 can maintain the precise shape and processing equivalent to that of the existing disc, significantly improve productivity, significantly reduce weight, and significantly reduce manufacturing costs. And the mass production of the butterfly valve can be realized.

In addition, although only the disc 100 is mentioned above, the structure of the disc 100 can be applied to fluid contact parts in other valves that require excellent corrosion resistance in addition to butterfly valves. That is, the fluid contact part may include a body made of metal, formed on the A first plastic layer on the body and made of high-strength plastic and a second plastic layer formed on the first plastic layer and made of fluororesin.

The plastic layers 560 and 562 of the body 104 will be described below. However, the components of the plastic layers 560 and 562 are the same, so only the plastic layer 560 will be described.

According to one embodiment, the plastic layer 560 may be composed of a mixture of polypropylene (PP) and glass fiber. Preferably, it may contain less than 40% and more than 0% glass fiber relative to the whole, and polypropylene (PP) has a content ratio greater than 60% relative to the whole. The experimental results are shown in Table 1 below.

It can be confirmed from the above Table 1 that when polypropylene (PP) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of a plastic layer composed only of polypropylene (PP) without glass fiber. That is, mechanical and chemical properties can be improved. However, when the content ratio of glass fiber exceeds 40%, the characteristics of the molding process used to manufacture the plastic layer 560 decrease, so it is difficult to manufacture the plastic layer 560 into a desired shape.

According to yet another embodiment, the plastic layer 560 may be composed of a mixture of polyphenylene sulfide (PPS) and glass fiber. Preferably, it may contain less than 40% and more than 0% glass fiber relative to the whole, Polyphenylene sulfide (PPS) has a content ratio of greater than 60% relative to the whole. The experimental results are shown in Table 2 below.

It can be confirmed from Table 2 above that when polyphenylene sulfide (PPS) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of polyphenylene sulfide (PPS) without glass fiber. Plastic layer. That is, the mechanical and chemical properties can be improved, so the plastic layer 560 can be formed with improved mechanical properties and is light and strong. However, when the content ratio of glass fiber exceeds 40%, the characteristics of the molding process used to manufacture the plastic layer 560 decrease, so it is difficult to manufacture the plastic layer 560 into a desired shape.

According to yet another embodiment, the plastic layer 560 may be composed of a mixture of polyphthalamide (PPA) and glass fiber. Preferably, the glass fiber content may be less than 55% and more than 0% relative to the whole, and the polyphthalamide (PPA) may have a content ratio greater than 45% relative to the whole. The experimental results are shown in Table 3 below.

It can be confirmed from Table 3 above that when polyphthalamide (PPA) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of polyphthalamide (PPA) without glass fiber. PPA) plastic layer. That is, the mechanical and chemical properties can be improved, so the plastic layer 560 can be formed with improved mechanical properties and is light and strong. However, when the content ratio of glass fiber exceeds 55%, the characteristics of the molding process used to manufacture the plastic layer 560 decrease, so it is difficult to manufacture the plastic layer 560 into a desired shape.

According to another embodiment, the plastic layer 560 may be composed of a mixture of polyamide (PA6) and glass fiber. Preferably, it may contain less than 50% and more than 0% glass fiber relative to the whole, and polyamide (PA6) has a content ratio greater than 50% relative to the whole. The experimental results are shown in Table 4 below.

It can be confirmed from Table 4 above that when polyamide (PA6) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of a plastic layer composed only of polyamide (PA6) without glass fiber. . That is, the mechanical and chemical properties can be improved, so the plastic layer 560 can be formed with improved mechanical properties and is light and strong. However, when the content ratio of glass fiber exceeds 50%, the characteristics of the molding process used to manufacture the plastic layer 560 decrease, so it is difficult to manufacture the plastic layer 560 into a desired shape.

According to another embodiment, the plastic layer 560 may be composed of a mixture of polyamide (PA66) and glass fiber. Preferably, it may contain less than 50% and more than 0% glass fiber relative to the whole, and polyamide (PA66) has a content ratio greater than 50% relative to the whole. The experimental results are shown in Table 5 below.

From the above Table 5, it can be confirmed that when polyamide (PA66) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of the plastic layer made only of polyamide (PA66) without glass fiber. . That is, it can improve mechanical and chemical properties, so it can form Plastic layer 560 with improved mechanical properties, light and strong. However, when the content ratio of glass fiber exceeds 50%, the characteristics of the molding process used to manufacture the plastic layer 560 are reduced, so it is difficult to manufacture the plastic layer 560 into a desired shape.

According to another embodiment, the plastic layer 560 may be composed of a mixture of polyketone and glass fiber. Preferably, it may contain less than 40% and more than 0% glass fiber relative to the whole, and polyketone (POK) has a content ratio greater than 60% relative to the whole. The experimental results are shown in Table 6 below.

It can be confirmed from Table 6 above that when polyketone (POK) and glass fiber are mixed to form the plastic layer 560, the tensile strength of the plastic layer 560 is significantly higher than that of a plastic layer composed only of polyketone (POK) without glass fiber. That is, the mechanical and chemical properties can be improved, so the plastic layer 560 can be formed with improved mechanical properties and is light and strong. However, when the content ratio of glass fiber exceeds 40%, the characteristics of the molding process used to manufacture the plastic layer 560 decrease, so it is difficult to manufacture the plastic layer 560 into a desired shape.

The scope of the present invention shall be subject to the scope of the patent application. All changes or deformations derived from the meaning, scope and equivalent concepts of the patent application shall be interpreted as being included in the scope of the present invention.

100a: Opening and closing part

100b: Operation Department

102a: first support part

102b: Second support part

104a: Upper body

104b: Lower body

200,202:hole

204:Opening part

208:Space

209:Slot

220,222:Screw

230a, 232a, 234a, 236a: screw insertion part

240,242,246: Locking parts

Claims (15)

A butterfly valve includes: a body part, which forms an insertion space; and a disc, which is inserted into the insertion space of the body part, and the disc opens and closes the flow of a fluid by rotating. The disc includes: a The disk body is made of metal; a first plastic layer is formed on the disk body and is made of a first plastic; and a second plastic layer is formed on the first plastic layer and The material is a second plastic, the melting point of the first plastic is higher than the melting point of the second plastic, and as the first plastic layer or the second plastic layer covers the entire disc body, the disc body has no Exposed to the outside, the disc body is formed by a skeleton structure. The skeleton structure has a rim and a plurality of spokes crossing the center of the rim. A fan-shaped internal space is formed between the spokes, and the A first plastic layer is formed on the disc body to fill the internal space between the spokes. The butterfly valve of claim 1, wherein: the first plastic layer is made of engineering plastic or super engineering plastic, and the second plastic layer is made of fluororesin, The fluorine resin is polytetrafluoroethylene (PTFE), perfluoroalkyl resin (Perfluoro alkyl, PFA) or polyvinylidene fluoride (PVDF). The butterfly valve of claim 1, wherein: the corrosion resistance or acid resistance of the second plastic is better than that of the first plastic, and the strength of the first plastic is better than that of the first plastic. The second plastic has excellent strength properties. The butterfly valve according to claim 1, wherein: the body part includes an upper body and a lower body, the upper body and the lower body are combined to form the insertion space, and at least one of the upper body and the lower body further includes A frame is made of steel and a plastic layer is formed on the frame. A pipe coupling portion for coupling the butterfly valve to a pipe protrudes from the frame. The butterfly valve as described in claim 4, wherein: the plastic layer passes through a polyvinyl chloride (Polyvinyl Chloride, PVC), a polypropylene (PP), a polyphenylene sulfide (Poly Phenylene sulfide, PPS) , a polyphthalamide (Polyphtalamide, PPA), a polyamide (Polyamide, PA6), a polyamide (Polyamide, PA66), a polyketone (Polyketone, POK) or a polyethylene (Polyethylene, PE ) is formed by mixing a glass fiber. The butterfly valve of claim 4, wherein: the plastic layer is formed by mixing the polypropylene and the glass fiber. When the content of the polypropylene exceeds 60% by weight, the content of the glass fiber is less than 40% by weight. and exceeds 0% by weight. The butterfly valve as described in claim 4, wherein: the plastic layer passes through polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), poly It is formed of amide (PA6), polyamide (PA66), polyketone (POK) or polyethylene (PE) mixed with glass fiber (Glass fiber) and carbon fiber. The butterfly valve as described in claim 4, wherein: the plastic layer passes through polyvinyl chloride (PVC), polypropylene (PP), polyphenylene sulfide (PPS), polyphthalamide (PPA), poly It is formed by mixing amide (PA6), polyamide (PA66), polyketone (POK) or polyethylene (PE) with glass fiber (Glass fiber), carbon fiber and graphite. The butterfly valve according to claim 1, further comprising: a disc support part that supports the disc in the insertion space and is made of fluororesin, and the disc support part includes a first support part and a first The two support parts are formed with a space penetrating the front and back of the first support part. The disc is inserted into the space. The second support part is coupled to a groove formed on the upper end of the first support part and extends toward the first support part. The body of the disc applies pressure to stably fix the body of the disc to the first support part. An operating part of the disc protrudes to the upper end of the disc body and penetrates the first support part and the third support part. The holes at the upper ends of the two supporting parts are exposed to the outside, and the fixing part protruding from the lower end of the disk body penetrates the holes of the first supporting part and the second supporting part and is inserted into the groove of the body part, When the operating part is rotated, the disc rotates to open and close the flow of the fluid. A disc for a butterfly valve, including: a disc body made of metal; a first plastic layer formed on the disc body and made of a first plastic; and A second plastic layer, which is formed on the first plastic layer and is made of a second plastic. The melting points of the first plastic and the second plastic are different, and as the first plastic layer or the second plastic layer Covering the entire disc body, the disc body is not exposed to the outside. The disc body is formed by a skeleton structure. The skeleton structure has a rim and a plurality of spokes intersecting at the center of the rim, A fan-shaped internal space is formed between the spokes, and the first plastic layer is formed on the disc body to fill the internal space between the spokes. The disk according to claim 10, wherein: the first plastic layer is made of engineering plastic or super engineering plastic, and the second plastic layer is made of a fluororesin, and the fluororesin is polytetrafluoroethylene (PTFE), Fluoroalkyl resin (Perfluoro alkyl, PFA) or polyvinylidene fluoride (PVDF). A body part covering a disc in a butterfly valve, including: an upper body and a lower body. The upper body and the lower body are combined to form an insertion space. The disc is inserted into the insertion space. The upper body is connected to the lower body. At least one of the lower bodies includes a frame made of metal and a plastic layer formed on the frame. The frame of the upper body is included in the plastic layer of the upper body. The frame of the lower body is included in the plastic layer. In the plastic layer of the lower body, the skeleton of the upper body can be separated from the skeleton of the lower body, A bottom is formed on one end of the frame of the upper body and one end of the frame of the lower body respectively, and the frame of the upper body and the frame of the lower body are combined through the bottoms, and with the The plastic layer of the upper body and the plastic layer of the lower body cover the frame of the upper body and the frame of the lower body, and the outer surfaces of the frame of the upper body and the frame of the lower body are not exposed to the outside, A pipe joint part, the pipe joint part is formed with a hole for connecting the pipe and the butterfly valve, the pipe joint part protrudes from the frame of the upper body or the lower body, and by inserting the fixing part into the frame hole and the hole of the pipe to which the butterfly valve is coupled. The body part according to claim 12, wherein: the plastic layer is made of polyvinyl chloride (Polyvinyl Chloride, PVC), polypropylene (PP), polyphenylene sulfide (Poly Phenylene sulfide, PPS), polyphthalate Formed by mixing diamide (Polyphtalamide, PPA), polyamide (Polyamide, PA6), polyamide (Polyamide, PA66), polyketone (POK) or polyethylene (Polyethylene, PE) mixed with glass fiber (Glass fiber) . A fluid contact part in contact with fluid in a valve includes: a body, which is made of metal and requires mechanical processing; a first plastic layer, which is formed on the body and is made of a first plastic; and a second A plastic layer is formed on the first plastic layer and is made of a second plastic. The first plastic layer and the second plastic layer are formed by molding. The melting points of the first plastic and the second plastic are different. ,and As the first plastic layer or the second plastic layer covers the entire body, the body is not exposed to the outside. The body is formed by a skeleton structure. The skeleton structure has a rim and a rim intersecting at the center of the rim. A plurality of spokes form a fan-shaped internal space between the spokes, and the first plastic layer is formed on the body to fill the internal space between the spokes. A method of manufacturing a disc for a butterfly valve, including: forming a first plastic layer on a disc body made of metal by molding; and forming a first plastic layer on the first plastic layer by molding. In the step of forming a second plastic layer, the first plastic as the material of the first plastic layer and the second plastic as the material of the second plastic layer have different melting points, and as the first plastic layer or the second plastic layer The plastic layer covers the entire disc body, and the disc body is not exposed to the outside. The disc body is formed by a skeleton structure, which has a rim and a plurality of cross-sections at the center of the rim. Spokes, a fan-shaped internal space is formed between the spokes, and the first plastic layer is formed on the disc body to fill the internal space between the spokes.