Ferrule joint
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- MT ENDEAVOUR INC
- Filing Date
- 2023-07-20
- Publication Date
- 2026-07-23
AI Technical Summary
Existing ferrul joints experience uneven sealing due to uneven gasket deformation over time, leading to fluid leakage and the need for frequent replacement.
The ferrul joint design features a gasket with inclined seal surfaces and pressure surfaces that apply force in the direction of the fluid flow, allowing the gasket to spread uniformly and maintain a stable seal, even under high pressure and temperature conditions.
This design ensures a stable seal effect by balancing the force across the gasket, extending its lifespan and maintaining airtightness in harsh fluid environments.
Smart Images
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Abstract
Description
[Technical field]
[0001] The present invention relates to a ferrule joint that is easy to assemble and disassemble. The ferrule joint is also called a ferrule joint. In this specification, the ferrule joint and the ferrule joint are collectively referred to as a ferrule joint. [Background technology]
[0002] Ferrule fittings have features such as excellent cleanability, and are relatively easy to disassemble and assemble. As just a few examples, they are extremely useful as fittings for connecting pipes for carrying fluids in the food and pharmaceutical fields, as well as in the field of precision technology such as semiconductors.
[0003] A typical ferrule joint for connecting pipes includes, for example, a first joint part having a first ferrule part, a second joint part having a second ferrule part, a gasket provided between the first ferrule part and the second ferrule part, and a clamp member that applies a force in a direction in which the first ferrule part and the second ferrule part press the gasket. The first joint part is provided on one side along the axis of the pipe, and the second joint part is provided on the other side, with the first ferrule part positioned on the one side and the second ferrule part positioned on the other side, sandwiching the gasket between the first ferrule part and the second ferrule part, and the first ferrule part and the second ferrule part are sealed by sandwiching the gasket between them by clamping the first ferrule part and the second ferrule part. This makes it possible to prevent leakage of fluid flowing through the pipe.
[0004] In general, the surfaces of the first ferrule part and the second ferrule part on the gasket side form a plane perpendicular to the axis of the pipe. The clamp member compresses the gasket between the first ferrule part and the second ferrule part, elastically deforming the gasket, and the reaction force of the gasket prevents leakage of the fluid flowing through the pipe. However, in reality, it is difficult to compress the gasket uniformly, and the elastic deformation of the gasket becomes uneven. This unevenness in the elastic deformation increases over time. As a result, various adverse effects appear in the relationship with the fluid flowing through the pipe. For example, as a result, the sealing performance becomes uneven, and adverse effects such as the fluid in the pipe entering the inside of the seal part are observed. In order to prevent these adverse effects, the gasket is replaced with a new one in a short period of time. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] Utility Model Registration No. 3152172 [Patent Document 2] Patent No. 6718346 Summary of the Invention [Problem to be solved by the invention]
[0006] In the flanged pipe joint 1 described in Patent Document 1, flanges 2 are provided on one side and the other side in the axial direction of a pipe 3, which is a piping, so as to sandwich an elastic gasket 8 therebetween. The flanges 2 on one side and the other side are fastened to each other with bolts 20 and nuts 22. Here, the surfaces of the flanges 2 on one side and the other side that sandwich the elastic gasket 8 are both positioned at right angles to the axis of the pipe 3, which is a piping. Furthermore, the flanges 2 on one side and the other side are fastened with a plurality of bolts 20 and nuts 22 to maintain sealing properties. In Patent Document 1, a V-shaped lip portion 14 is formed on the inner surface of the elastic gasket 8, and the elastic gasket 8 presses the flanges 2 on one side and the other side when fluid pressure acts on the V-shaped lip portion 14.
[0007] The structure in which the flanges 2 on one side and the other side are fastened with a plurality of bolts 20 and nuts 22 is easy to disassemble and assemble, and is excellent in terms of maintenance. However, the above-mentioned problem arises here. That is, stress unevenness occurs in the elastic gasket 8, and unevenness occurs in the sealing performance over time. For example, elastic unevenness occurs in the elastic gasket 8, and a problem occurs in which the sealing performance is partially impaired. The configuration of Patent Document 1 is thought to be based on an attempt to reinforce the sealing performance by the V-shaped lip portion 14 of the elastic gasket 8 due to the fluid pressure flowing through the pipe 3. However, this measure is insufficient, and the elastic gasket 8 is used for a short period of time, and measures such as replacing it with a new elastic gasket 8 arise. It is necessary to fundamentally improve the problem regarding the improvement of sealing performance.
[0008] The ferrule joint 11 described in Patent Document 2 has one and other ferrules 13 arranged to sandwich a ferrule gasket 12. The ferrule gasket 12 has a flat surface 23 extending in a direction perpendicular to the direction of fluid movement. The one and other ferrules 13 each have an opposing surface 34, and the one and other ferrules 13 are configured to sandwich the flat surface 23 of the ferrule gasket 12 between their respective opposing surfaces 34 and press the flat surface 23 of the ferrule gasket 12 based on the force of the clamp 14.
[0009] The same can be said about Patent Document 2 as about Patent Document 1. When the flat surface 23 of the ferrule gasket 12 is pressed by the ferrule 13 having a surface perpendicular to the axial direction of the fluid flow, the pressing force acts uniformly, and the flat surface 23 of the ferrule gasket 12 is uniformly deformed, so that it is very difficult to perform a uniform sealing action against the fluid. Generally, it becomes uneven. At first, the ferrule gasket 12 has excellent elasticity, but as time passes, the ferrule gasket 12 is affected by uneven pressure acting on it, and the sealing ability becomes biased. For this reason, a phenomenon occurs in which the fluid partially seeps between the ferrule gasket 12 and the ferrule 13, causing problems. As a result, it becomes necessary to take measures such as replacing the ferrule gasket 12 in a short period of time.
[0010] An object of the present invention is to provide a ferrule joint capable of maintaining a stable sealing effect. [Means for solving the problem]
[0011] [First invention] A first invention for solving the above problems provides a ferrule joint having a one-side joint part having a one-side seal part, a other-side joint part having a other-side seal part, an annular gasket located between the one-side seal part and the other-side seal part, and a clamp that applies a force to the one-side seal part and the other-side seal part in a direction in which they approach each other, wherein the gasket is pressed by the one-side seal part and the other-side seal part based on the force from the clamp, the one-side seal portion of the one-side joint portion has a one-side pressing surface that presses the gasket, and the other-side seal portion of the other-side joint portion has a other-side pressing surface that presses the gasket, the one-side pressing surface of the one-side seal portion and the other-side pressing surface of the other-side seal portion are inclined with respect to a plane perpendicular to a flow direction of a fluid flowing through the one-side joint portion and the other-side joint portion so as to move away from each other from a center side of the one-side joint portion and the other-side joint portion toward an outside, the one-side seal surface and the other-side seal surface of the gasket are inclined with respect to a plane perpendicular to the flow direction of the fluid flowing through the one-side joint part and the other-side joint part so as to move away from each other from the center side of the one-side joint part and the other-side joint part toward the outside, a pressure surface of the gasket that is in contact with the first seal portion and the second seal portion of the second seal portion, the pressure surface of the gasket that is in contact with the first seal portion and the second seal portion of the second seal portion, and the pressure surface of the gasket that is in contact with the first seal portion and the second seal portion of the second seal portion acts on the gasket in a direction that expands the gasket toward the outer periphery, which is a direction that increases the diameter of the gasket. A ferrule joint characterized in that
[0012] [Second Invention] In the ferrule joint of the first invention, The gasket has a tubular shape; the gasket has a one-side seal surface on the one-side seal portion side, the one-side seal surface being pressed by the one-side pressing surface, the gasket has the other-side seal surface on the other-side seal portion side, the other-side seal surface being pressed by the other-side pressing surface, a length between the one-side seal surface and the other-side seal surface increases from a center side to an outer periphery side of the gasket, a pressure applied from the one-side pressing surface of the one-side seal portion to the one-side seal surface of the gasket, and a pressure applied from the other-side pressing surface to the other-side seal portion of the gasket, causing a force to act on the tubular gasket in a direction in which the diameter of the tubular shape expands, causing the tubular gasket to deform in a radial direction, and a seal between the one-side seal portion and the other-side joint portion is maintained by the deformation of the gasket in the radial direction, the pressure from the one-side pressing surface, and the pressure from the other-side pressing surface. A ferrule joint characterized in that
[0013] [Explanation of the Effects of the First and Second Inventions] In the section explaining the function and effect of the invention, reference signs related to the configuration of the embodiment corresponding to the configuration of the invention are used for easy understanding. This is not intended to limit the configuration of the invention to the configuration of the embodiment, but is merely for the purpose of making the explanation easier to understand. Note that, in the explanation of the function and effect of other inventions below, similarly, reference signs related to the configuration of the embodiment corresponding to the configuration of the invention are used for easy understanding. This is not intended to limit the configuration of the invention to the configuration of the embodiment, but is merely for the purpose of making the explanation easier to understand.
[0014] In joints based on conventional technology, the gasket has a sealing surface that extends in a direction perpendicular to the direction of movement of the fluid flowing inside the joint, in other words, the axis of movement of the fluid. The one-side pressing surface of the one-side joint part that applies pressure to the gasket and the other-side pressing surface of the other-side joint part are also perpendicular to the axis of movement of the fluid. When the pressure of the fluid moving inside the joint is low, a gasket that deforms very greatly in response to the applied pressure, such as soft rubber, can be used. Therefore, even if there is unevenness in the characteristics or unevenness in the applied pressure, the large amount of deformation absorbs the unevenness, making it easy to maintain a good sealing effect.
[0015] However, when the fluid pressure becomes high, a gasket that deforms a lot cannot be used. To obtain a sealing effect in such a joint, it is necessary for the gasket to be able to withstand the application of a large pressure to the one-side pressing surface 124 of the one-side joint part 112 and the other-side pressing surface 154 of the other-side joint part 142. In this case, a gasket that deforms a little is used. If a gasket that deforms a little is used in a joint of a conventional configuration, it becomes difficult to maintain the function of preventing fluid leakage, as described above. For this reason, in conventional joints, the gasket must be replaced after a relatively short period of use.
[0016] In the present invention, the gasket 160 and the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 are pressed against each other not on a surface perpendicular to the fluid movement axis, which is the flow direction of the fluid 20, but on an inclined surface. As a result, the gasket 160 having the one-side seal surface 164 and the other-side seal surface 166 receives a force in a direction that causes the gasket 160 as a whole to expand in the outer circumferential direction. By receiving this force in the direction that causes the gasket 160 as a whole to expand in the outer circumferential direction, a repulsive force is generated in a direction that causes the gasket 160 itself to compress in the radial direction.
[0017] In the conventional structure, the sealing action is generated by simply pressing the gasket sealing surface against the pressing surface in a plane. In such a conventional structure, the sealing action depends on the individual partial conditions. Therefore, unevenness in the sealing action occurs due to unevenness in the pressure pressing the gasket sealing surface, and partial variation in the characteristics of the gasket sealing surface and the pressing surface that presses it, and the individual unevenness has a large effect on the whole as the period of use increases. As mentioned above, this is a major obstacle when it is necessary to use a material that has a small deformation amount against pressure as the gasket.
[0018] In the present invention, the gasket 160 is structured so that the sealing effect is determined as a whole, not based on a collection of sealing effects of each part of the gasket 160. That is, the gasket 160 is structured so that a force (force in the direction of arrow 24 in FIG. 4) always acts from the center toward the outer periphery in the radial direction of the annular shape of the gasket 160, and the gasket 160 generates a reaction force against the force acting in the outer periphery direction in the radial direction. The sealing action between the one-side pressing surface 124 of the one-side seal portion 122 or the other-side pressing surface 154 of the other-side seal portion 152 and the one-side seal surface 164 or the other-side seal surface 166 of the gasket 160 is generated by a structure in which a force always acts from the center toward the outer periphery in the radial direction of the annular shape of the gasket 160 and a reaction force of the gasket 160 that faces the force always collide with each other.
[0019] In the prior art, the sealing action is regarded as the result of a collection of individual sealing actions at individual parts, but in the present invention, the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160 as a whole are pressed by the one-side pressing surface 124 and the other-side pressing surface 154, which are in close contact with and press the one-side seal surface 164 and the other-side seal surface 166, and the sealing action is generated based on the balance state between the force in the radial direction of the entire gasket 160 in the radial direction of the outer periphery and the reaction force of the entire gasket 160. The balance of the above two forces determines the positional relationship between the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160 and the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152, and this positional relationship changes. This configuration of the present invention can eliminate individual partial sealing unevenness. As a result, the service life of the gasket 160 can be extended.
[0020] Furthermore, the positions of one-side seal portion 122 and the other-side seal portion 152 that are integrated with one-side joint portion 112 and the other-side joint portion 142 and are closest to the center of the flow passage are integrated with one-side joint portion 112 and the other-side joint portion 142, and in the conventional configuration, pressure cannot be applied to one-side seal surface 164 and the other-side seal surface 166 of gasket 160. However, in the present invention, gasket 160 itself always generates a reaction force in the direction of reducing the diameter, as described above, so a good sealing effect can be maintained.
[0021] [Third Invention] A ferrule joint according to a second aspect of the present invention is a ferrule joint, characterized in that the pressure of the fluid moving inside the ferrule joint is 1 MPa or more.
[0022] [Fourth Invention] A ferrule joint according to a third invention is a ferrule joint, characterized in that the temperature of the fluid moving inside the ferrule joint is 150 degrees Celsius or higher.
[0023] [Fifth Invention] A ferrule joint according to a fifth invention is a ferrule joint according to any one of the first to fourth inventions, characterized in that the one side joint portion and the other side joint portion are made of a metal material, and the gasket is made of an engineering plastic.
[0024] [Sixth Invention] A ferrule joint according to a sixth aspect of the present invention is the ferrule joint according to the fifth aspect of the present invention, the one-side seal portion has a one-side outer circumferential portion covering a part of an outer circumferential surface of the gasket, the other-side seal portion has an other-side outer peripheral portion that covers a part of the outer peripheral surface of the gasket, a holder for holding a gasket is provided between the other-side seal portion or the other-side outer peripheral portion and the outer peripheral surface of the gasket.
[0025] [Effects of the sixth aspect of the invention] When assembling the ferrule joint 100, assembly is very easy if the gasket 160 is held in the one-side joint portion 112 or the other-side joint portion 142. In the sixth invention, the ferrule joint 100 can be assembled in a state in which the gasket 160 is held in the one-side seal portion 122 or the other-side seal portion 152 by the holder 210, the holder 221, or the holder 222.
[0026] [Seventh Invention] A ferrule joint according to a seventh aspect of the present invention is the ferrule joint according to the fourth aspect of the present invention, a perpendicular axis is set to represent the direction of a plane perpendicular to the movement direction of the fluid, and an angle θ between the perpendicular axis and the one-side pressing surface of the one-side seal part of the one-side joint part and the other-side pressing surface 1 of the other-side seal part of the other-side joint part is in the range of 10 degrees to 40 degrees.
[0027] [Eighth Invention] The ferrule joint of the eighth invention is the ferrule joint of the seventh invention, a ferrule joint, wherein an angle θ202 between the one-side seal surface or the other-side seal surface of the gasket and the perpendicular axis is smaller than the angle θ between the one-side pressing surface of the one-side seal portion of the one-side joint portion or the other-side pressing surface of the other-side seal portion of the other-side joint portion and the perpendicular axis. Effect of the Invention
[0028] According to the present invention, a ferrule joint capable of maintaining a stable sealing effect can be obtained. [Brief description of the drawings]
[0029] [Figure 1] FIG. 1 is an explanatory diagram showing a state in which a ferrule joint 100 to which the present invention is applied is in use. [Diagram 2] FIG. 2 is a cross-sectional view of the ferrule fitting 100. [Diagram 3] FIG. 3 is an explanatory diagram for explaining the configuration of the first clamp 182 and the second clamp 192. As shown in FIG. [Figure 4] FIG. 4 is an explanatory diagram for explaining the effects of the invention described in the embodiment. [Diagram 5] FIG. 5 is an explanatory diagram showing the specific relationship between the inclination angle of the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 and the inclination angle of the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160. [Figure 6] FIG. 6 is an explanatory diagram for explaining another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] 1. Introduction The embodiments to which the present invention is applied will be described below with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals are used to designate the same components, and the components to which the same reference numerals are used perform the same operations and effects, and achieve the same effects. The repeated description of the components to which the same reference numerals are used will be omitted to avoid complication.
[0031] 2. Description of the basic configuration of the ferrule joint 100 to which the present invention is applied (1) Overall structure of the ferrule fitting 100 FIG. 1 is a diagram for explaining the use state of the ferrule joint 100. The fluid 20 to which high pressure is applied is moving from the other side pipe 34 to the one side pipe 32 as shown by the arrow 22. The moving direction of the fluid 20 shown by the arrow 22 is an example, and even if the moving direction is reversed, the action and effect of each configuration related to the ferrule joint 100 is exactly the same. The other side pipe 34 and the one side pipe 32 for flowing the fluid 20 are connected to each other by the ferrule joint 100. In the connection by the ferrule joint 100, it is natural that the fluid 20 should not leak at the joint between the other side pipe 34 and the one side pipe 32. However, it is also desired to avoid the formation of a gap into which the fluid 20 enters or a gap that obstructs the flow, etc., on the sealing surface of the gasket 160 for sealing described below, or around the inner surface of the gasket 160. For example, if the fluid 20 enters a gap somewhere and stagnates for a long time, it may cause decay or chemical changes, which is not preferable.
[0032] The one-side joint portion 112 is provided with a one-side seal portion 122 for sealing to prevent leakage, and the other-side joint portion 142 is provided with a other-side seal portion 152. FIG. 2 is a cross-sectional view of FIG. 1 cut along the moving direction of the fluid 20. As shown in FIG. 2, a gasket 160 for sealing is provided between the one-side seal portion 122 and the other-side seal portion 152. A one-side clamp 182 and an other-side clamp 192 are provided to sandwich the gasket 160 between the one-side seal portion 122 and the other-side seal portion 152 and apply a predetermined pressure to the gasket 160. Note that the one-side pipe 32 and the other-side pipe 34 are present inside the one-side joint portion 112 and the other-side joint portion 142, respectively, but are not illustrated.
[0033] (2) Description of one side clamp 182 and other side clamp 192 1, 2 and 3, in this embodiment, two clamps, a one-side clamp 182 and an other-side clamp 192, are provided in the vertical direction in the one-side seal portion 122 of the one-side joint portion 112 and the other-side seal portion 152 of the other-side joint portion 142. The first clamp 182 and the second clamp 192 have a one-side clamp surface 183 and an other-side clamp surface 184, and a one-side clamp surface 193 and an other-side clamp surface 194, respectively. The one-side clamp surface 183 and the other-side clamp surface 184, and the one-side clamp surface 193 and the other-side clamp surface 194 are wide on the side where the fluid 20 is located, and conversely, are narrow on the side of the bottom of the annular recess 187 and the recess 197, which are the outer circumferential side. Therefore, by sandwiching one side seal portion 122 and the other side seal portion 152 inside the annular recess 187 and recess 197 created by the first clamp 182 and the second clamp 192 and tightening with a bolt 197 and a nut 187, the first clamp 182 and the second clamp 192 can be tightened in the direction of the arrow 12 and the arrow 14, which are directions that reduce the diameter of the first clamp 182 and the second clamp 192.
[0034] The clamp is divided into a plurality of parts. In this embodiment, it is divided into two parts, a first clamp 182 and a second clamp 192. The first clamp 182 has a one-side fastener 188, and the second clamp 192 has an other-side fastener 198, to which a bolt 199 is fixed. Therefore, by making the bolt 199 pass through the center of the one-side fastener 188 and tightening it with a nut 189, it becomes possible for the first clamp 182 and the second clamp 192 to apply a force in a direction to bring the one-side joint portion 112 and the other-side joint portion 142 closer to each other. The one-side joint portion 112 and the other-side joint portion 142 are annular in shape. The one-side seal portion 122 provided in the one-side joint portion 112 and the other-side seal portion 152 provided in the other-side joint portion 142 are also cylindrical in shape. The one-side seal portion 122 and the other-side seal portion 152 have a length along the moving direction of the fluid 20 at the center side in the radial direction, i.e., at the portion connected to the one-side joint portion 112 and the other-side joint portion 142, in other words, the thickness is the thickest. The annular one-side seal portion 122 and the other-side seal portion 152 have a shape that becomes thinner as it moves away from the fluid 20 side, i.e., as the diameter of the annular shape becomes larger. The outer peripheral surface portion of the one-side seal portion 122 and the other-side seal portion 152 is the thinnest.
[0035] As described above, one-side clamp 182 and other-side clamp 192 each have recesses 187 and 187 of the same shape, and recesses 187 and 197 have a shape in which the smaller diameter is wider and the width becomes narrower as the diameter increases. Therefore, by applying a force to one-side clamp 182 in the direction of arrow 12 and further applying a force to the other-side clamp 192 in the direction of arrow 14, the force compressing gasket 160 described below by one-side seal portion 122 and other-side seal portion 152 increases. The compressive force of gasket 160 can be adjusted by the bolts 199 and nuts 189.
[0036] (3) Description of the seal structure between the one-side joint portion 112 and the other-side joint portion 142 2 to 4, a seal structure consisting of the one-side seal portion 122, the other-side seal portion 152, and the gasket 160 will be described. The fluid 20 flowing inside the ferrule joint 100 is pressurized, for example, to 1 M (mega) Pascal or more. In some cases, it is pressurized to 2 M (mega) Pascal or more. It is also desired that there be no problem even if the temperature is heated to 150 degrees Celsius or more. For these reasons, the gasket 160 is made of engineering plastics with high chemical resistance, such as tetrafluoroethylene and polyether ether ketone. In addition, the one-side joint portion 112 having the one-side seal portion 122 and the other-side joint portion 142 having the other-side seal portion 152 are made of metals such as stainless steel. The gasket 160 may be made of metal instead of engineering plastic.
[0037] The gasket 160 has an annular shape with a trapezoidal cross section. The one-side joint part 112 and the other-side joint part 142 also have an annular shape, and the inner surfaces of the gasket 160, the one-side joint part 112, and the other-side joint part 142, which are the surfaces on the fluid 20 side, have approximately the same diameter. Therefore, the inner surface 162 of the gasket 160 forms approximately the same surface as the inner surfaces of the one-side joint part 112 and the other-side joint part 142.
[0038] The cross section of the gasket 160 is narrow in the direction of fluid flow on the side through which the fluid 20 passes, and the width becomes wider as it moves away from the fluid 20, i.e., the diameter becomes larger, and the width becomes wider as it approaches the outer circumferential surface. A one-side seal surface 164 is formed on one side of the gasket 160, which has a trapezoidal cross section, in the direction along the fluid movement axis, and is in contact with the one-side pressing surface 124 of the one-side seal portion 122, and is constantly pressed by the one-side pressing surface 124 to perform a sealing action. Also, a second-side seal surface 166 is formed on the side of the other-side seal portion 152 of the trapezoidal cross section. The other-side seal surface 166 is constantly pressed by the other-side pressing surface 154 of the other-side seal portion 152, and performs a sealing action between the other-side pressing surface 154 and the other-side seal surface 166.
[0039] The shape formed by one-side fastening surface 123 of one-side seal portion 122 and the other-side fastening surface 153 of the other-side seal portion 152 is a trapezoid, and the distance between them becomes narrower from the fluid 20 side to the outer periphery. As described above, first clamp 182 presses one-side seal portion 122 and the other-side seal portion 152 in the direction of arrow 12 and second clamp 192 presses one-side seal portion 122 and the other-side seal portion 152 in the direction of arrow 14, whereby one-side seal portion 122 and the other-side seal portion 152 are pressed in a direction approaching each other. Therefore, one-side pressing surface 124 of one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 press one-side seal surface 164 and the other-side seal surface 166 of gasket 160, and a force indicated by arrow 24 acts on gasket 160 as shown in FIG. 4. 4 shows only a portion of the gasket 160, a force in a direction increasing the diameter of the gasket 160 acts over the entire circumference of the gasket 160. Meanwhile, the gasket 160 generates a reaction force against the force of the arrow 24 over the entire circumference of the gasket 160.
[0040] (4) Explanation of the Function and Effect of the One-Side Seal Portion 122 and the Other-Side Seal Portion 152 and the Gasket 160 In joints based on conventional technology, the gasket has a sealing surface that extends in a direction perpendicular to the direction of movement of the fluid flowing inside the joint, in other words, the axis of movement of the fluid. The one-side pressing surface of the one-side joint part that applies pressure to the gasket and the other-side pressing surface of the other-side joint part are also perpendicular to the axis of movement of the fluid. When the pressure of the fluid moving inside the joint is low, a gasket that deforms very greatly in response to the applied pressure, such as soft rubber, can be used. Therefore, even if there is unevenness in the characteristics or unevenness in the applied pressure, the large amount of deformation absorbs the unevenness, making it easy to maintain a good sealing effect.
[0041] However, when the fluid pressure becomes high, a gasket that deforms a lot cannot be used. To obtain a sealing effect in such a joint, it is necessary for the gasket to be able to withstand the application of a large pressure to the one-side pressing surface 124 of the one-side joint part 112 and the other-side pressing surface 154 of the other-side joint part 142. In this case, a gasket that deforms a little is used. If a gasket that deforms a little is used in a joint of a conventional configuration, it becomes difficult to maintain the function of preventing fluid leakage, as described above. For this reason, in conventional joints, the gasket must be replaced after a relatively short period of use.
[0042] In the invention described in the embodiments, the gasket 160 and the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 are pressed against each other not on a surface perpendicular to the fluid movement axis, which is the flow direction of the fluid 20, but on an inclined surface. As a result, the gasket 160 having the one-side seal surface 164 and the other-side seal surface 166 is subjected to a force in a direction that causes the gasket 160 as a whole to expand in the circumferential direction. By receiving this force in the direction that causes the gasket 160 as a whole to expand in the circumferential direction, a repulsive force is generated in a direction that causes the gasket 160 itself to compress in the radial direction.
[0043] In the conventional structure, the sealing action is generated by simply pressing the gasket sealing surface against the pressing surface in a plane. In such a conventional structure, the sealing action depends on the individual partial conditions. Therefore, unevenness in the sealing action occurs due to unevenness in the pressure pressing the gasket sealing surface, and partial variation in the characteristics of the gasket sealing surface and the pressing surface that presses it, and the individual unevenness has a large effect on the whole as the period of use increases. As mentioned above, this is a major obstacle when it is necessary to use a material that has a small deformation amount against pressure as the gasket.
[0044] In the invention described in the embodiment, the gasket 160 is structured so that the sealing effect is determined as a whole, not based on a collection of sealing actions of each part of the gasket 160. That is, the gasket 160 is structured so that a force (force in the direction of arrow 24 in FIG. 4) always acts from the center toward the outer periphery in the radial direction of the annular shape of the gasket 160, and a reaction force of the gasket 160 that opposes the force acting in the outer periphery direction in the radial direction is generated. The sealing action between the one-side pressing surface 124 of the one-side seal portion 122 or the other-side pressing surface 154 of the other-side seal portion 152 and the one-side seal surface 164 or the other-side seal surface 166 of the gasket 160 is generated by a structure in which a force always acts from the center toward the outer periphery in the radial direction of the annular shape of the gasket 160 and the reaction force of the gasket 160 that opposes this force always collide with each other.
[0045] In the prior art, the sealing action is regarded as the result of a collection of individual sealing actions at individual parts, but in the present invention, the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160 as a whole are pressed by the one-side pressing surface 124 and the other-side pressing surface 154, which are in close contact with and press the one-side seal surface 164 and the other-side seal surface 166, and the sealing action is generated based on the balance state between the force in the radial direction of the entire gasket 160 in the radial direction of the outer periphery and the reaction force of the entire gasket 160. The balance of the above two forces determines the positional relationship between the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160 and the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152, and this positional relationship changes. This configuration of the present invention can eliminate individual partial sealing unevenness. As a result, the service life of the gasket 160 can be extended.
[0046] Furthermore, the positions of one-side seal portion 122 and the other-side seal portion 152 that are integrated with one-side joint portion 112 and the other-side joint portion 142 and are closest to the center of the flow passage are integrated with one-side joint portion 112 and the other-side joint portion 142, and in the conventional configuration, pressure cannot be applied to one-side seal surface 164 and the other-side seal surface 166 of gasket 160. However, in the present invention, gasket 160 itself always generates a reaction force in the direction of reducing the diameter, as described above, so a good sealing effect can be maintained.
[0047] (5) Application areas and others The ferrule fitting 100 described in this embodiment can be used in the food and pharmaceutical fields where hygiene control is extremely important. Furthermore, airtightness is extremely important in these fields. The ferrule fitting 100 of this embodiment is also excellent in these respects.
[0048] It is also extremely effective as a joint for fluids used in the semiconductor field, etc. It is optimal as a joint for pipes with an aperture of 1 inch or more, such as the one side pipe 32 and the other side pipe 34 in FIG.
[0048] In FIG. 4, as described above, the one-side seal surface 164 and the other-side seal surface 166 of the gasket 160 are inclined, not perpendicular, to the flow direction of the fluid 20. In addition, the one-side pressing surface 124 of the one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 are also inclined with respect to a plane perpendicular to the flow direction of the fluid 20. If the plane perpendicular to the flow direction of the fluid 20 is indicated by a perpendicular axis 200, the other-side pressing surface 154 is in the direction of the pressing axis 201 and is inclined at an angle θ. Although not shown, the one-side pressing surface 124 is inclined at the same angle θ as the other-side pressing surface 154. Due to these inclinations, a force in the direction of the arrow 24 is generated in the gasket 160 by the pressure of the one-side pressing surface 124 and the other-side pressing surface 154, and the gasket 160 generates a reaction force in the direction opposite to the arrow 24, that is, in the direction of contraction from the outer periphery of the diameter of the annular shape toward the center. The angle θ of the one-side pressing surface 124 and the other-side pressing surface 154 with respect to the perpendicular axis 200, which indicates a direction perpendicular to the flow direction of the fluid 20, is 5 degrees or more, and preferably 10 degrees or more. The maximum angle of the inclination angle θ is 80 degrees, and the angle θ is an angle less than this. Preferably, the angle is 40 degrees or less. Although the pressing axis 201 is described with respect to the other-side seal surface 166, it is preferable that the one-side seal surface 164 and the other-side seal surface 166 have the same inclination angle, i.e., angle θ.
[0049] One-side seal surface 164 and other-side seal surface 166 of gasket 160 also have an inclination angle substantially the same as angle θ. In this embodiment, angle θ of one-side pressing surface 124 of one-side seal portion 122 and angle of other-side pressing surface 154 of other-side seal portion 152 are slightly larger in angle than one-side seal surface 164 and other-side seal surface 166 of gasket 160. A specific example will be described with reference to FIG. 5.
[0050] In FIG. 5, the perpendicular axis 200 represents a plane perpendicular to the axis of the fluid flow. The pressing axis 201 is a plane along the other-side pressing surface 154 of the other-side seal portion 152. The seal angle 206, which represents the angle of the plane along the other-side seal surface 166 of the gasket 160 with respect to the angle θ of the pressing axis 201 with respect to the perpendicular axis 200, is set smaller than the angle θ of the pressing axis 201. As described above, the seal angle 206 may be set to the same as the angle θ, but by making the seal angle 206 smaller than the angle θ, the following effect is achieved. The angle by which the seal angle 206 is smaller than the angle θ is 5 degrees or less.
[0051] The positions at which first clamp 182 and second clamp 192 apply pressure to one-side seal portion 122 and the other-side seal portion 152 are on the outer circumferential side in the radial direction of annular one-side seal portion 122 and the other-side seal portion 152, that is, in the radial direction, than the positions at which one-side pressing surface 124 of one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 apply pressure to gasket 160. In other words, these are locations with larger diameters. For this reason, the pressure of first clamp 182 and second clamp 192 causes one-side seal portion 122 and the other-side seal portion 152 to bend slightly in the radial direction. For this reason, making the inclination angle of one-side seal surface 164 and the other-side seal surface 166 of gasket 160 smaller than that of one-side pressing surface 124 of one-side seal portion 122 and the other-side pressing surface 154 of the other-side seal portion 152 has the effect of making the pressure distribution in the radial direction of one-side seal surface 164 and the other-side seal surface 166 more uniform.
[0052] The one-side seal portion 122 and the other-side seal portion 152 have a one-side opposing portion 126 and an other-side opposing portion 156 that are close to each other at a position radially beyond the gasket 160. The one-side opposing surface 128 of the one-side opposing portion 126 and the other-side opposing surface 158 of the other-side opposing portion 156 face each other with a predetermined narrow gap between them. When the pressing force of the first clamp 182 or the second clamp 192 becomes large, the one-side opposing surface 128 and the other-side opposing surface 158 collide with each other, and the maximum pressing force that can be applied from the first clamp 182 or the second clamp 192 to the one-side seal portion 122 or the other-side seal portion 152 is determined, and even if a pressing force greater than this is applied, the pressing force acting on the gasket 160 is restricted. Therefore, the maximum pressing force on the gasket 160 is determined. This is important from the viewpoint of safety, etc.
[0053] (6) Description of Assembly of Ferrule Fitting 100 2 and 3 show the ferrule joint 100 after assembly is completed. The advantage of the ferrule joint 100 is that it can be easily disassembled and assembled. The gasket 160 is assembled with the one side joint part 112 or the other side joint part 142. In this case, if the gasket 160 can be held in the one side joint part 112 or the other side joint part 142, it becomes easy to assemble the remaining one side joint part 112 or the other side joint part 142.
[0054] The one-side seal portion 122 and the other-side seal portion 152 are provided with a one-side outer periphery portion 125 and an other-side outer periphery portion 155 that face a part of the outer periphery of the gasket 160, further outside the outer periphery of the gasket 160. By providing the one-side outer periphery portion 125 on the one-side seal portion 122 of the one-side joint portion 112, it becomes possible to fix the gasket 160 to the one-side seal portion 122 by inserting a retainer 210 between the outer periphery of the gasket 160 and the inside of the one-side outer periphery portion 125. If the gasket 160 is fixed to the one-side seal portion 122 of the one-side joint portion 112, it becomes easy to assemble the other-side joint portion 142. Similarly, the gasket 160 may be fixed to the other-side joint portion 142 by hand. In this case, by inserting a retainer 210 between the inner surface of the other-side outer peripheral portion 155 of the other-side joint portion 142 and the outer peripheral surface of the gasket 160, it becomes possible to temporarily fix the gasket 160 to the other-side seal portion 152 of the other-side joint portion 142, and further make it possible to assemble the one-side seal portion 122.
[0055] With the gasket 160 sandwiched between the one-side joint part 112 and the other-side joint part 142, the first clamp 182 and the second clamp 192 are further attached with bolts 199 and nuts 189, thereby making it possible to assemble the ferrule joint 100. By providing the one-side outer periphery 125 and the other-side outer periphery 155 further outside the outer periphery of the gasket 160, the one-side fastening surface 123 of the one-side seal part 122 and the other-side fastening surface 153 of the other-side seal part 152 can be made to have a large angle, and the first clamp 182 and the second clamp 192 can stably apply a force to the one-side seal part 122 and the other-side seal part 152 in a direction that brings them closer to each other, which is also very effective in this respect.
[0056] In the embodiment shown in FIG. 4, the retainer 210 is made of an elastic material that is much softer than the gasket 160. Therefore, it can be easily deformed by a human operation during assembly. In addition, the retainer 210 has an annular shape, and being held by the gasket 160 makes it very convenient to handle. Therefore, by forming an uneven surface between the inside of the retainer 210 and the outer circumferential surface of the gasket 160, it becomes possible to hold the retainer 210 to the gasket 160 by utilizing the soft elastic force of the annular retainer 210.
[0057] Fig. 6 shows an alternative to the embodiment shown in Fig. 4. By providing a holder 221 or a holder 222 on the outer peripheral surface of the gasket 160, it becomes possible to temporarily fix the gasket 160 to the one-side seal portion 122 or the other-side seal portion 152. This makes it easier to assemble the one-side joint portion 112 and the other-side joint portion 142.
[0058] (7) Other effects As shown in FIG. 3 and FIG. 4, the one-side seal portion 122 provided in the one-side joint portion 112 and the other-side seal portion 152 provided in the other-side joint portion 142 are annular in shape, and their respective radial lengths L2 are much longer than the radial length L1 of the annular gasket 160. The radial lengths L2 of the one-side seal portion 122 and the other-side seal portion 152 are at least twice the radial length L1 of the gasket 160. Furthermore, the position where the first clamp 182 applies pressure to the one-side seal portion 122 and the other-side seal portion 152 is a position further outside the outermost circumference of the annular gasket 160. The relationship between the second clamp 192 and the one-side seal portion 122 and the other-side seal portion 152 is also the same. This configuration has the effect of making assembly easy. In other words, there is an effect that the first clamp 182 and the second clamp 192 can be easily assembled to the one side joint part 112 and the other side joint part 142 .
[0059] Furthermore, one-side joint part 112 and other-side joint part 142 are made of a metal such as stainless steel and have elasticity, which allows them to absorb vibrations of first clamp 182 and second clamp 192, or vibrations of one-side piping 32 and other-side piping 34 shown in FIG. [Explanation of symbols]
[0060] 20 fluid, 32 one side piping, 34 other side piping, 100 ferrule joint, 112 one side joint portion, 122 one side seal portion, 123 one side fastening surface, 124 one side pressing surface, 125 one side outer periphery, 142 other side joint portion, 152 other side seal portion, 153 other side fastening surface, 154 other side pressing surface, 155 other side outer periphery, 160 gasket, 162 inner surface, 164 one side seal surface, 166...other side sealing surface, 182...first clamp, 183...one side clamping surface, 184...other side clamping surface, 187...recess, 188...one side fastening tool, 189...nut, 192...second clamp, 193...one side clamping surface, 194...other side clamping surface, 197...recess, 198...other side fastening tool, 199...bolt, 202...gap, 204...gap, 210...retaining tool, 221...retaining tool, 222...retaining tool.
Claims
1. A ferrule joint comprising: a one-sided joint having a one-sided seal portion; a other-sided joint having a other-sided seal portion; an annular gasket provided between the one-sided seal portion and the other-sided seal portion; and a clamp that applies a force to the one-sided seal portion and the other-sided seal portion in a direction that brings them closer together, wherein the gasket is pressed by the one-sided seal portion and the other-sided seal portion based on the force from the clamp, The gasket has a sealing surface on one side of the joint and a sealing surface on the other side of the joint. The aforementioned one-sided sealing surface and the aforementioned other-sided sealing surface are inclined so as they move away from each other as they extend outward from the center in the radial direction of the annular gasket. The one-side sealing portion of the one-side joint has a one-side pressing surface for pressing against the one-side sealing surface of the gasket, and the other-side sealing portion of the other-side joint has a other-side pressing surface for pressing against the other-side sealing surface of the gasket. The pressing surface on one side of the sealing portion and the pressing surface on the other side of the sealing portion are inclined to move away from each other as they move outward from the center of the joint portion on one side and the joint portion on the other side. The force applied by the clamp to the one-sided sealing portion and the other-sided sealing portion causes the one-sided sealing surface and the other-sided sealing surface of the gasket to be pressed by the one-sided pressing surface of the one-sided sealing portion and the other-sided pressing surface of the other-sided sealing portion. A ferrule fitting characterized by the following features.
2. In the ferrule joint described in claim 1, The width between the one sealing surface and the other sealing surface of the annular gasket increases from the center side toward the outer circumference. The pressure applied to the one-side sealing portion of the gasket from the one-side pressing surface and the pressure applied to the other-side sealing portion of the gasket from the other-side pressing surface act on the annular-shaped gasket in a direction that expands the diameter of the annular shape, causing the annular-shaped gasket to deform in a direction that increases its diameter in the radial direction. A force is generated within the gasket itself to resist the deformation in the radial direction, and the gasket itself exerts a force that attempts to suppress the deformation, thereby balancing the pressure from the one-side pressing surface and the other-side pressing surface and maintaining the sealing action between the one-side sealing portion and the other-side sealing portion and the gasket. A ferrule fitting characterized by the following features.
3. A ferrule joint according to claim 2, characterized in that the pressure of the fluid moving inside the ferrule joint is 1 M Pascal or more.
4. A ferrule joint according to claim 3, characterized in that the temperature of the fluid moving inside the ferrule joint is 150 degrees Celsius or higher.
5. A ferrule joint according to one of claims 1 to 4, characterized in that the one-side joint portion and the other-side joint portion are made of a metal material, and the gasket is made of engineering plastic.
6. In the ferrule joint according to claim 4, The aforementioned one-side sealing portion has a one-side outer peripheral portion that covers a part of the outer peripheral surface of the gasket, The other side sealing portion has the other side outer periphery portion that covers a part of the outer periphery surface of the gasket, A ferrule joint characterized in that a retainer for holding the gasket is provided between the outer peripheral portion of one side and the outer peripheral portion of the other side and the outer peripheral surface of the gasket.
7. In the ferrule joint described in claim 4, A ferrule joint characterized in that, when a right-angle axis is set representing the direction of a surface perpendicular to the direction of fluid movement, the first angle formed between the one-side pressing surface of the one-side seal portion of the one-side joint portion or the other-side pressing surface of the other-side seal portion of the other-side joint portion and the right-angle axis is in the range of 10 degrees to 40 degrees.
8. In the ferrule fitting according to claim 7, A ferrule joint characterized in that the second angle formed between the one-sided sealing surface or the other-sided sealing surface of the gasket and the right-angle axis is smaller than the first angle formed between the one-sided pressing surface of the one-sided sealing portion of the one-sided joint or the other-sided pressing surface of the other-sided sealing portion of the other-sided joint and the right-angle axis.