JP2013151964A - Resin ferrule joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin ferrule joint structure hardly deformed even when used over a long period.SOLUTION: A resin ferrule joint structure includes a ferrule flange, and a backup flange for contacting with an outer surface of the ferrule flange. A surface for contacting with the backup flange of the ferrule flange has a projection-shaped part in an annular shape, a surface for contacting with the ferrule flange of the backup flange has a recessed-shaped part in an annular shape, and the projection-shaped part and the recessed-shaped part are fitted.

Description

  The present invention relates to a resin ferrule joint.

  It is essential that the piping of the food and pharmaceutical manufacturing process be clean. Therefore, the pipes are manufactured seamlessly or connected by ferrule joints defined in the IDF (International Dairy Federation) standard so that they can be easily disassembled and washed.

  The pipes are generally made of metal, but when sanitary environmental compatibility and corrosion resistance are required, such as pipes for beverage transfer used for bottling, PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer) Resin piping such as coalesced) is preferred.

  A ferrule part (ferrule joint) of a conventional resin pipe is shown in FIG. 2 (however, the lower half is omitted. The same applies to the following figures). The conventional resin ferrule joint 150 includes a resin ferrule flange 15 including the end 5 of the pipe 4 and the liquid contact portion 7, and a metal backup for reinforcing the ferrule flange 15 in contact with the outer surface of the ferrule flange 15. And a flange 25. The ferrule flange 15 has a tapered surface on the side in contact with the backup flange 25, and the backup flange 25 has a tapered surface on the side in contact with the ferrule flange 15 and on the opposite side. The ferrule flange 15 and the backup flange 25 are in contact with each other via a tapered surface. That is, the backup flange 25 is substantially uniform in thickness and has a simple taper shape along the outer surface shape of the ferrule flange 15.

  The ferrule flange 15 is in contact with the ferrule gasket 3 at the end face, and the surface of the ferrule gasket 3 in contact with the ferrule flange 15 has an annular convex portion (that is, a lip shape in the circumferential direction) near the outer peripheral end. The surface in contact with the ferrule gasket 3 has a concave portion (that is, a groove shape in the circumferential direction) fitted into the convex portion of the ferrule gasket 3 in an annular shape. The ferrule flange 15 and the ferrule gasket 3 are brought into contact with each other through fitting in an annularly formed uneven portion (that is, a circumferential groove-lip shape), thereby improving the sealing performance of the resin ferrule joint 150. . By sealing the outer surfaces of the two backup flanges 25 in contact with the outer surfaces of the two ferrule flanges 15 sandwiching the ferrule gasket 3 with a clamp band, the sealing performance of the resin ferrule joint 150 is ensured.

  The ferrule joint 150 is connected to the pipe body through the welded portion 6. The stopper 8 is a metallic one-cut ring for fixing the backup flange 25, and fits into a groove provided on the outer peripheral surface of the ferrule flange 15 along the back side surface of the seal surface of the backup flange 25. To do.

  When the conventional resin ferrule joint 150 is used for a long period of time, the ferrule flange 15 whose outer surface is constrained is subjected to creep due to long-term tightening, thermal cycle of liquid passing through the pipe 4, or tensile force and compressive force repeatedly applied to the pipe 4. As a result, the sealability is impaired and the liquid passing through the pipe 4 may leak from the ferrule joint 150.

  Specifically, as shown in FIG. 3, the ferrule flange 15 is deformed by Δd toward the radial center at the liquid contact portion 7 of the pipe end 5 due to stress and thermal contraction inside the resin during long-term use. Then, the end face of the pipe end 5 is deformed into a taper shape at an angle of θ. Along with this, ΔC deformation is performed in the radial center side at the concave portion near the outer peripheral end in contact with the ferrule gasket 3 and ΔD deformation is performed in the radial central side at the outer peripheral end. Therefore, the tightening surface pressure between the ferrule gasket 3 and the ferrule flange 15 due to Δd and θ is insufficient and the sealing performance is lowered, and the tightening surface between the ferrule gasket 3 and the ferrule flange 15 due to ΔC and ΔD. As a result of the pressure being insufficient and the sealing performance being lowered, the liquid passing through the pipe 4 may leak from the ferrule joint 150.

  An object of this invention is to provide the resin ferrule joint structure which hardly deform | transforms even if it uses it for a long period of time.

  In order to solve the above-mentioned problems, the present inventors have intensively studied, and as a result, by providing an annular concavo-convex portion that can be fitted to the surface where the ferrule flange and the backup flange are in contact with each other, The present inventors have found that deformation can be suppressed and completed the present invention.

  The present invention provides a resin ferrule joint structure, the joint structure comprising a ferrule flange and a backup flange in contact with the outer surface of the ferrule flange, and the surface of the ferrule flange in contact with the backup flange has an annular convex portion. And the surface of the backup flange in contact with the ferrule flange has an annular concave portion, and the convex portion and the concave portion are fitted.

  In one embodiment, the joint structure further includes a ferrule gasket in contact with the end face of the ferrule flange, and a surface of the ferrule gasket in contact with the ferrule flange has an annular convex portion near an outer peripheral end; The surface of the ferrule flange that contacts the ferrule gasket has an annular concave portion that fits with the convex portion of the ferrule gasket, and the annular convex portion of the surface that contacts the backup flange of the ferrule flange The shape of the ferrule flange is a shape along the annular concave portion of the surface in contact with the ferrule gasket.

  In one embodiment, the ferrule flange is made of a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer.

  In one embodiment, the material of the backup flange is stainless steel.

  According to the present invention, it is possible to provide a resin ferrule joint structure that hardly deforms even after long-term use.

It is a longitudinal cross-sectional view (however, the lower half is abbreviate | omitted) which shows one embodiment of the resin ferrule joint structure of this invention. It is a longitudinal cross-sectional view (however, the lower half is abbreviate | omitted) which shows the embodiment of the conventional resin ferrule joint. It is a longitudinal cross-sectional view (however, the lower half is abbreviate | omitted) which shows the deformation | transformation which arises in the embodiment of the conventional resin ferrule joint. It is a longitudinal cross-sectional view which shows the modification of the resin ferrule joint structure of this invention. It is a longitudinal cross-sectional view which shows the modification of the resin ferrule joint structure of this invention.

  One embodiment of the resin ferrule joint structure of the present invention is shown in FIG. The resin ferrule joint 100 according to an embodiment of the present invention reinforces the ferrule flange 10 that is in contact with the outer surface of the ferrule flange 10 and the ferrule flange 10 that includes the end 5 of the pipe 4 and the liquid contact portion 7. The backup flange 20 is provided. The surface of the ferrule flange 10 that contacts the backup flange 20 has an annular (concentric circular) convex portion (that is, a lip shape in the circumferential direction), and the surface of the backup flange 20 that contacts the ferrule flange 10 has an annular concave portion (that is, And a groove shape in the circumferential direction). The annular convex portion on the surface of the ferrule flange 10 in contact with the backup flange 20 and the annular concave portion on the surface of the backup flange 20 in contact with the ferrule flange 10 are fitted.

  The resin ferrule joint 100 of the present invention further includes a ferrule gasket 3 in contact with the end face of the ferrule flange 10, similarly to the conventional resin ferrule joint 150. The surface of the ferrule gasket 3 that contacts the ferrule flange 10 has an annular convex portion (that is, a lip shape in the circumferential direction) near the outer peripheral end, and the surface of the ferrule flange 10 that contacts the ferrule gasket 3 has an annular shape. A concave portion (that is, a groove shape in the circumferential direction) that fits with the convex portion. The ferrule flange 10 and the ferrule gasket 3 are in contact with each other through fitting in an annular concavo-convex portion (that is, a circumferential groove-lip shape), thereby improving the sealing performance of the resin ferrule joint 100. By tightening the outer surfaces of the two backup flanges 20 in contact with the outer surfaces of the two ferrule flanges 10 with the ferrule gasket 3 interposed therebetween, a seal of the resin ferrule joint 100 is secured.

  The resin ferrule joint 100 of the present invention is connected to the pipe main body through the welded portion 6, similarly to the conventional resin ferrule joint 150. The stopper 8 is fitted in a groove provided on the outer peripheral surface of the ferrule flange 10 along the side surface on the back side of the seal surface of the backup flange 20 in order to fix the backup flange 20.

  The shape of the annular convex portion on the surface of the ferrule flange 10 in contact with the backup flange 20 is not particularly limited as long as it is convex and can be fitted into the concave portion on the surface of the opposing backup flange 20. Preferably, the cross-sectional shape along the tube axis is a semicircle. Similarly, the shape of the annular concave portion on the surface that contacts the ferrule flange 10 of the backup flange 20 is not particularly limited as long as it is concave and can be fitted to the convex portion on the surface of the opposing ferrule flange 10. Preferably, the cross-sectional shape along the tube axis is a semicircle.

  By providing an annular concavo-convex portion (that is, a circumferential groove-lip shape) that can be fitted to the surface where the ferrule flange 10 and the backup flange 20 are in contact with each other, the ferrule flange 10 can be piped even in long-term use. Since deformation at the center of the radial direction at the liquid contact portion 7 of the end 5 is suppressed and the end surface of the pipe end 5 is also suppressed from being tapered at an angle θ, the ferrule gasket 3 and the ferrule flange 10 As a result of maintaining the sealing performance for a long time, it is possible to effectively prevent the liquid passing through the pipe 4 from leaking from the ferrule joint 100.

  Preferably, the annular convex portion on the surface of the ferrule flange 10 in contact with the backup flange 20 (that is, the circumferential lip shape) is the annular concave portion on the surface of the ferrule flange 10 in contact with the ferrule gasket 3 (that is, in the circumferential direction). (Groove shape). In this case, since the thickness of the ferrule flange 10 is substantially uniform in the tube axis direction, it is resistant to creep due to long-term tightening, thermal cycle of liquid passing through the pipe 4, or tensile force and compressive force repeatedly applied to the pipe 4. As a result, the ferrule flange 10 is deformed inward and the sealing performance is lowered. As a result, the liquid passing through the pipe 4 can be effectively prevented from leaking from the ferrule joint 100.

  In the above-described embodiment, the shape of the side surface of the ferrule flange 10 that contacts the backup flange 20 and the shape of the side surface of the backup flange 20 that contacts the ferrule flange 10 are concave groove shapes on the side surface of the ferrule flange 10 that contact the ferrule gasket 3. Although the case where it was set as the curved shape which followed was demonstrated, the inclination shape (refer FIG. 4) or step shape (refer FIG. 5) along a ditch | groove shape may be sufficient, for example.

  The material of the ferrule flange of the present invention is not particularly limited. For example, fluorine such as PFA, FEP (tetrafluoroethylene / hexafluoropropylene copolymer), PVdF (polyvinylidene fluoride), PTFE (polytetrafluoroethylene), etc. Examples of the resin include general-purpose resins such as silicon, PE (polyethylene), PP (polypropylene), PVC (polyvinyl chloride), and nylon. Since the ferrule joint used in the manufacturing process of foods and pharmaceuticals is required to be clean and non-adhesive, it is preferably a fluororesin. More preferably, it is PFA.

  The material of the backup flange of the present invention is not particularly limited as long as the coefficient of thermal expansion is lower than that of the ferrule flange. For example, a metal or a resin such as PEEK, POM (polyoxymethylene (polyacetal resin)), PPS (polyphenylene sulfide resin) can be used. An example of the metal is stainless steel. Preferably, it is stainless steel.

  According to the present invention, it is possible to provide a resin ferrule joint structure that hardly deforms even after long-term use. The resin ferrule joint structure of the present invention can greatly reduce the burden of maintenance such as retightening and gasket replacement.

DESCRIPTION OF SYMBOLS 10 Ferrule flange of this invention 15 Conventional ferrule flange 20 Backup flange of this invention 25 Conventional backup flange 3 Ferrule gasket 4 Piping 5 Piping end 6 Welding part 7 Wet part 8 Stopper 100 Resin ferrule joint 150 of this invention 150 Conventional Plastic ferrule joint θ Deformation angle ΔC Deformation dimension ΔD Deformation dimension Δd Deformation dimension

Claims (4)

  A resin ferrule joint structure, comprising a ferrule flange and a backup flange in contact with the outer surface of the ferrule flange, the surface of the ferrule flange in contact with the backup flange has an annular convex portion, and the backup flange A joint structure in which the surface in contact with the ferrule flange has an annular concave portion, and the convex portion and the concave portion are fitted.   And a ferrule gasket in contact with the end face of the ferrule flange, the surface of the ferrule gasket in contact with the ferrule flange has an annular convex portion near the outer peripheral end, and the surface of the ferrule flange in contact with the ferrule gasket Has a concave portion that fits annularly with the convex portion of the ferrule gasket, and the annular convex portion of the surface that contacts the backup flange of the ferrule flange is on the surface of the ferrule flange that contacts the ferrule gasket. The joint structure according to claim 1, wherein the joint structure has a shape along the annular concave portion.   The joint structure according to claim 1 or 2, wherein a material of the ferrule flange is a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer.   The joint structure according to any one of claims 1 to 3, wherein a material of the backup flange is stainless steel.

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