JP5033102B2 - Pipe fitting - Google Patents

Description

  The present invention relates to a pipe joint provided between fluid pipes for joining a plurality of fluid pipes.

When joining multiple fluid pipes with pipe joints, thermal expansion and thermal contraction occur due to changes in the temperature of the fluid product flowing through the pipes at the joints between the pipes and pipe joints. An excessive load is applied to the provided seal member, and there is a possibility that the seal member deteriorates early and is damaged.
For this reason, the said pipe joint absorbs these loads flexibly, and while preventing the early deterioration of the said sealing member, the function which prevents the failure | damage of a fluid pipe | tube is required.
As a pipe joint having the above function, a pipe joint having an expandable pipe part formed in a bellows shape has been proposed (Patent Document 1).
As shown in FIG. 2, the pipe joint 70 according to Patent Document 1 includes a pipe body 74 composed of a bellows 73 having a peak portion 71 and a valley portion 72, and axially opposite ends 74 a and 74 b of the pipe body 74. And flange portions 75 and 75 for connecting to a fluid pipe (not shown in FIG. 2).
On the outer periphery of the bellows 73, a covering portion 76 made of a rubber member thicker than the outer periphery of the bellows 73 is formed, and in the covering portion 76, an expansion and contraction absorbing portion that absorbs expansion and contraction in the axial direction of the tube main body 74. 77.
In the expansion / contraction absorption part 77, a U-shaped notch part 78 is formed in a part covering the valley part 72 of the pipe body 74.
In the pipe joint 70, since the covering portion 76 is formed of a thicker rubber member than the bellows 73, the pipe joint 70 is excellent in vibration proofing and vibration damping, and can eliminate the influence on external impact. Is possible.
Therefore, the property of the metal member and the property of the rubber member can complement each other, can also protect from the radial direction of the tube body 74, absorb the expansion and contraction in the axial direction of the tube body 74, The anti-vibration pipe joint 70 having excellent amplitude strength, stretch strength, bending strength, and the like can be provided.

However, in the case of the pipe joint 70 according to Patent Document 1, since the pipe body 74 is formed of the bellows 73, the fluid product tends to stay on the inner surface of the peak portion 71 of the bellows 73 and stay. .
Therefore, when the pipe joint 70 is used in a line for sterilizing a fluid product with high-temperature steam, the condensed water of the sterilization steam stays on the inner surface of the peak portion 71 inside the pipe joint 70. At the site where the condensed water has accumulated, the sterilization temperature has not been reached, and sterilization failure may occur, or product cleaning may become difficult.
Further, the bellows 73 of the pipe joint 70 is made of metal and has high rigidity, so that flexible expansion and contraction is difficult.
Further, due to thermal expansion of the fluid pipe, the force applied to the pipe main body 74 is biased to one of the radial directions, and the notches that cover the valley 72 and the valley 72 in a part of the axial direction of the pipe main body 74. There was also a problem that the load was concentrated on the portion 78 and the tube main body 74 was bent into a U shape or a wavy shape.
JP 2008-51333 A

  Therefore, the technical problem of the present invention is to prevent the occurrence of sterilization defects in the steam sterilization line by preventing the retention of fluid products and steam sterilized condensate in the interior, and the thermal expansion of the fluid pipe in the pipe joint. An object of the present invention is to provide a pipe joint in which a load concentrates on a part of the pipe joint even when a force due to the above is applied and is not bent and damaged.

In order to solve the above-mentioned problems, the invention according to claim 1 is made of a fluorine-based resin, and has an inner peripheral surface formed smoothly and an expandable / contractible tube portion that can be expanded and contracted in the axial direction, and the expandable tube. And an anti-bending member formed of an elastic material that can disperse an axial load of the expansion tube portion, and the expansion tube portion is formed in an overall cylindrical shape. A plurality of recesses provided along the circumferential direction are arranged on the outer periphery of the telescopic tube part at predetermined intervals along the axial direction, and the deflection preventing member is a rubber material that can be fitted into the recess. It is formed from the annular member which consists of .

  Therefore, since the inner surface of the expansion / contraction tube part is smooth, the fluid product does not stay inside, and the expansion / contraction of the expansion / contraction tube part is caused even when an axial load is generated in the expansion / contraction tube part due to the thermal expansion of the fluid pipe. Since the tube part is made of fluororesin, it can be shrunk flexibly compared to metal, and the load at the time of shrinkage is uniformly distributed throughout the stretchable tube part by the elastic material, and a part of the stretchable tube part This prevents the occurrence of bending.

Further, the upper SL telescopic pipe unit is formed on the entire cylindrical and the outer periphery of the expansion pipe section recess provided along the circumferential direction, a plurality of arranged spaced a predetermined distance along the axial direction the deflection preventing member is that formed from an annular member made of a rubber material that can fit in the recess.

  Therefore, when an axial load is applied to the expansion / contraction tube portion due to thermal expansion of the fluid tube, the load is evenly distributed throughout the expansion / contraction tube portion by the annular member disposed in the recess, and It is possible to prevent a situation in which the load concentrates on the part and causes bending.

The invention according to claim 2 further comprises a radial regulating member that is disposed radially outward of the telescopic tube portion and that can regulate expansion of the telescopic tube portion in the radial direction. .

In the invention according to claim 3 , the radial direction regulating member is formed of a plurality of metal ring-shaped members arranged at a predetermined interval along the axial direction of the telescopic tube portion. Features.
According to a fourth aspect of the present invention, the radial direction regulating member is formed of a metal pipe member having a diameter that can cover the telescopic pipe part from the outside. To do.

  Therefore, even when the inside of the telescopic tube portion is in a high pressure state, the expansion of the telescopic tube portion outward in the radial direction is restricted by the radial direction regulating member.

In the invention according to claim 5, the pipe joint side flange connected to the fluid pipe side flange provided at the end of the fluid pipe at the end of the extension pipe at both ends of the extension pipe And a member for preventing excessive expansion / contraction, which can restrict expansion / contraction in the axial direction of the expansion / contraction tube portion, is disposed between the pipe joint side flanges at both ends of the expansion / contraction tube portion.

  Therefore, the expansion and contraction in the axial direction of the telescopic tube portion is restricted within a predetermined axial dimension range.

In the invention of claim 6 , the excessive expansion and contraction preventing member is formed in the shape of an elongated rod shorter than the axial interval between the pipe joint side flanges at both ends of the expansion tube portion, and at both ends. Is provided with a screw hole in the axial direction, and a through hole provided in the screw hole by communicating the fluid pipe side flange portion and the pipe joint side flange portion from the outside in the axial direction of the fluid pipe side flange portion. The male screw part of the screw member is formed to have a smaller diameter than the through hole, and the total of the fluid pipe side flange part and the pipe joint side flange part. A length dimension larger than the thickness dimension is formed, and the excessive expansion and contraction prevention member and the head of the screw member are formed to have a diameter dimension larger than the through hole, so that the screw member moves in the through hole. Mounts slidably over a specified length It is characterized in that is.

  Therefore, even if the expansion / contraction tube portion expands / contracts, the expansion / contraction range is restricted within the slidable range of the male screw portion.

The invention according to claim 7 is characterized in that the inner surface of the telescopic tube portion and the inner surface of the fluid tube body are formed in a smooth state.
Therefore, the fluid product does not stay at the boundary between the fluid pipe and the pipe joint.

The invention according to claim 8 is characterized in that the fluororesin is polytetrafluoroethylene.
Therefore, due to the nature of polytetrafluoroethylene, the odor and pigment of fluid products are difficult to deposit and the chemical resistance is high.

  The pipe joint according to the invention of claim 1 is made of a fluorine-based resin, and has an inner peripheral surface that is formed smoothly, and an expansion / contraction tube portion that can expand and contract in the axial direction, and is disposed radially outward of the expansion / contraction tube portion. And an anti-bending member formed of an elastic material that can disperse the axial load of the telescopic tube part, thereby preventing the retention of condensed fluid from the fluid product and steam sterilization inside the pipe joint. In addition to preventing the occurrence of sterilization defects in the steam sterilization line, even if a force due to thermal expansion of the fluid pipe is applied to the pipe joint, the load concentrates on a part of the pipe joint and bends and breaks. It is possible to provide a pipe joint that does not occur.

Further, the upper SL telescopic pipe unit is formed on the entire cylindrical and the outer periphery of the expansion pipe section recess provided along the circumferential direction, a plurality of arranged spaced a predetermined distance along the axial direction In addition, since the deflection preventing member is formed of an annular member made of a rubber material that can be fitted into the recess, even if a load due to thermal expansion or the like of the fluid pipe is applied to the pipe joint, With the bending preventing member made of a rubber material annular member, it is possible to provide a pipe joint in which the force is uniformly distributed over the entire area of the pipe joint, and the force does not concentrate and bend in a part of the pipe joint.

According to a second aspect of the present invention, there is provided a pipe joint including a radial direction regulating member that is disposed radially outward of the expansion and contraction pipe part and that can regulate expansion of the expansion and contraction pipe part in the radial direction.
In the third aspect , the radial direction restricting member is formed from a plurality of metal ring-shaped members arranged at predetermined intervals along the axial direction of the telescopic tube portion. It is formed from a metal tube member having a length dimension substantially the same as the axial direction of the telescopic tube portion and having a diameter that can cover the telescopic tube portion from the outside.
Therefore, in addition to the effect of the invention of claim 1, even if a force that expands in the radial direction is exerted on the expansion and contraction pipe part due to an increase in internal pressure of the expansion and contraction pipe part due to an increase in the flow rate of a fluid product, the metal The expansion is restricted by the ring-shaped member made of metal or the metal tube member, and the situation where the expansion tube portion is broken and the fluid product leaks is prevented.

Moreover, the pipe joint which concerns on Claim 5 has the pipe joint side flange part connected to the fluid pipe side flange part provided in the said expansion pipe part side edge part of the said fluid pipe at the both ends of the said expansion pipe part. Between the pipe joint side flanges provided at both ends of the expansion tube portion, an excessive expansion / contraction preventing member capable of restricting expansion / contraction in the axial direction of the expansion tube portion is disposed.
Further, in the pipe joint according to claim 6 , the member for preventing excessive expansion and contraction is formed in an elongated rod shape having a dimension shorter than the axial interval between the pipe joint side flanges at both ends of the expansion and contraction pipe section, and at both ends. A screw hole is provided in the axial direction, and a through-hole provided in communication with the fluid pipe side flange portion and the pipe joint side flange portion from the axial direction outside of the fluid pipe side flange portion is provided in the screw hole. And the male screw part of the screw member is formed to have a smaller diameter than the through hole, and the total thickness of the fluid pipe side flange part and the pipe joint side flange part. The overstretch prevention member and the head of the screw member are formed with a diameter larger than the through hole, so that the screw member is predetermined in the through hole. Slidably mounted over the length of It has been.
Therefore, in addition to the effect of the invention of claim 1, the expansion / contraction of the expansion tube portion is restricted within a predetermined range by the excessive expansion / contraction prevention member, so that the expansion / contraction tube portion is damaged by excessive expansion / contraction, and the fluid product Is prevented from leaking.

Further, in the pipe joint according to claim 6 , since the inner surface of the expansion tube portion and the inner surface of the fluid tube main body are formed in a smooth state, in addition to the effect of the invention of claim 1 , the expansion tube portion Stagnation is less likely to occur at the boundary between the inner surface and the fluid pipe body, and internal contamination due to stagnation of the fluid product is less likely to occur.

Further, since the fluororesin is polytetrafluoroethylene, in addition to the effect of the invention of claim 1, the odor or color deposition of the fluid product is prevented inside the pipe joint, and the resistance to chemicals is high. Since it is high, it is possible to provide a pipe joint that can be used for a long period of time.

Hereinafter, the embodiment of the present invention will be described with reference to the drawings, taking as an example the case where the radial direction regulating member is formed of a plurality of metal ring-shaped members.
As shown in FIG. 1, the pipe joint 10 is joined between the plurality of fluid pipes 11 and 12, and is formed so as to be expandable and contractable along the axial direction.
The pipe joint 10 is made of a fluororesin that is polytetrafluoroethylene, and has an inner peripheral surface that is formed smoothly, and an expandable and contractible pipe portion 13 that can be expanded and contracted in the axial direction. And an anti-bending member 14 made of an elastic material, which is an annular member made of a rubber material, which is disposed on the side and can disperse the axial load of the telescopic tube portion 13.
The telescopic tube portion 13 is formed in a cylindrical shape as a whole, and a plurality of recesses 15 provided along the circumferential direction are provided on the outer periphery of the telescopic tube portion 13 at predetermined intervals along the axial direction. The bending preventing member 14 which is an annular member made of the rubber material is fitted in the recess 15.
Further, a metal ring that is arranged at a predetermined interval along the axial direction of the telescopic tube portion 13 and that is capable of regulating expansion of the telescopic tube portion 13 in the radial direction outside the telescopic tube portion 13 in the radial direction. A radial direction regulating member 16 made of a member is disposed.
Further, pipe joints connected to the fluid pipe side flange portions 19 and 19 provided at the end portions 17 and 18 of the fluid pipes 11 and 12 are provided at both end portions 13a and 13b of the extension pipe portion 13, respectively. Side flange portions 20, 20 are provided, and between the pipe joint side flanges 20, 20 of the both ends of the expansion tube portions 13 a, 13 b, for preventing excessive expansion / contraction that can restrict expansion / contraction in the axial direction of the expansion tube portion 13. A member 21 is arranged.
The member 21 for preventing excessive expansion / contraction is formed in the shape of an elongated rod shorter than the axial distance between the flanges 20 and 20 of the pipe joints at both ends 13a and 13b of the expansion / contraction pipe, and shafts at both ends 21a and 21b. Screw holes 22 and 23 are provided in the direction, and the fluid pipe side flange part 19 and the pipe joint side flange part 20 are communicated with the screw holes 22 and 23 from the axially outer side of the fluid pipe side flange part 19. The screw members 26 and 27 are combined through the through holes 24 and 25 provided as described above, and the male screw portions 28 and 29 of the screw members 26 and 27 have a smaller diameter than the through holes 24 and 25. In addition to being formed, the fluid pipe side flange portion 19 and the pipe joint side flange portion 20 are formed to have a length dimension larger than the total thickness dimension P.
Further, the inner surface of the telescopic tube portion 13 and the fluid pipe main bodies 11 and 12 are joined so that the inner surfaces are smooth.

The configuration of the embodiment having the above configuration will be described with reference to the drawings.
As shown in FIG. 1, the pipe joint 10 includes fluid pipe side flange portions 19 and 19 and pipe joint side flange portions 20 and 20 through bolts 30 and 31 and nuts 32 and 33, respectively. 11 and 12 are joined and fixed.
Further, as shown in FIG. 1, fixing concave portions 34 and 35 are provided on the outer peripheral surface portions of both ends of the expansion tube portion 13 of the pipe joint 10, and the outer periphery of both ends of the expansion tube portion 13 has the above-described Split rings 38 and 39 having a L-shaped cross section having protrusions 36 and 37 that fit into the recesses 34 and 35 are disposed.
Further, on the inner peripheral surfaces of the pipe joint side flanges 20, 20, step portions 40, 41 that abut on the outer peripheral edge portions of the split rings 38, 39 are provided.
By tightening the bolts 30 and 31 and the nuts 32 and 33, the pipe joint side flanges 20 and 20 and the fluid pipe side flanges 19 and 19 are brought into close contact with each other, and the split rings 38 and 39 are formed by the step portions 40 and 41. Is pushed outward in the axial direction.
As a result, both end edges of the telescopic tube portion 13 are pulled outward in the axial direction by the protrusions 36 and 37 and are in close contact with the seal members 42 and 43 disposed on the fluid tube side flanges 19 and 19. And sealed.

The effect | action of the Example in the said structure is demonstrated.
A predetermined fluid product circulates inside the fluid pipe 11, the pipe joint 10, and the fluid pipe 12.
Since the inside of the telescopic pipe part 13 is formed smoothly, the fluid product flows down smoothly, and like the pipe joint 70 having a pipe body 74 made of the conventional bellows 73 shown in FIG. In this case, no stagnation of the fluid product occurs.
Moreover, even if it is a case where it uses for the line which disinfects a fluid product with high temperature steam, the condensed water of the said steam does not stay in the inside of the pipe joint 10. FIG.

Further, when the fluid pipes 11 and 12 are expanded in the axial direction due to an increase in the temperature of the fluid product or the outside air temperature, the pipe joints 10 are opposed to each other contracting toward the center in the axial direction. A load is applied, and the load is transmitted to the telescopic pipe part 13 via the pipe side flange parts 19 and 19 and the pipe joint side flange parts 20 and 20.
The telescopic tube portion 13 contracts toward the center in the axial direction due to the opposing load, but when the load is concentrated on a specific portion of the plurality of recesses 15 that absorb the axial contraction with respect to the opposing load. A force to bend in the radial direction acts on the telescopic tube portion 13.
Even in the above case, since the annular member 14 made of a rubber material is fitted into the recess 15 of the telescopic tube portion 13, the annular member 14 receives the load and the elastic force of the annular member 14. Thus, the load is distributed over the entire outer periphery of the expansion tube portion 13, and the distributed load is sequentially transmitted to the adjacent annular member 14, so that the load is distributed throughout the expansion tube portion 13, and the expansion tube portion 13 contracts uniformly in the axial direction. Therefore, partial bending of the telescopic tube portion 13 is prevented.

  As shown in FIG. 1, when the fluid pressure inside the fluid pipes 11 and 12 rises, the expansion pipe part 13 generates an expansion force in the radial direction, but the metal of the radial direction regulating member 16. Since the expansion of the expansion tube portion 13 in the radial direction is restricted within a predetermined range by the ring made of the ring, the expansion tube portion 13 is damaged due to excessive expansion, and the fluid product leaks to the outside. Is prevented.

As shown in FIG. 1, when the telescopic tube portion 13 contracts in the axial direction, the male screw portions of the screw members 26 and 27 screwed into the screw holes 22 and 23 of the excessive expansion and contraction prevention member 21. 28 and 29 are formed to have a smaller diameter than the through holes 24 and 25 communicating the fluid pipe side flange portion 19 and the pipe joint side flange portion 20, so that the fluid pipe side flange portions 19 and 19 The pipe joint side flange portions 20 and 20 are movable within the dimension Q in the direction of approaching each other in the axial direction along the male screw portions 28 and 29. Access to the length dimension or less of the excessive expansion / contraction preventing member 21 is restricted.
Even when the expansion tube portion 13 is extended, the screw members 28 and 29 separate the both end portions of the pipe joint side flanges 20 and 20 from the excessive expansion and contraction prevention member 21 beyond the dimension Q. To be regulated.
Therefore, it is possible to prevent the fluid product from leaking due to excessive expansion and contraction of the expansion tube portion 13.

  In the present embodiment, the radial direction regulating member 16 is formed in a metal ring shape. However, in the case where the radial direction regulating member 16 is formed in a cylindrical shape capable of covering the entire outer periphery of the telescopic tube portion 13 shown in FIG. Even if it exists, it is the same in the effect which regulates expansion | swelling of the radial direction of the said expansion-contraction pipe part 13. FIG.

  The present invention is widely applicable to a pipe joint provided between fluid pipes for joining a plurality of fluid pipes.

It is an axial sectional view of the pipe joint concerning the form of the example of the present invention. It is an axial sectional view of a conventional pipe joint having a bellows part.

DESCRIPTION OF SYMBOLS 10 Pipe joint 11 Fluid pipe 12 Fluid pipe 13 Extension tube part 13a End part 13b of extension tube part End part 14 of extension tube part Deflection prevention member (annular member of rubber material)
15 Concave portion 16 Radial direction regulating member 17 End portion 18 on the side of the expansion / contraction tube portion of the fluid pipe End portion 19 on the side of the expansion / contraction tube portion of the fluid pipe 19 Flange portion 20 on the pipe joint side Excess expansion / contraction prevention member 21a Part 21b Excess expansion / contraction prevention member end part 22 Screw hole 23 Screw hole 24 Through hole 25 Through hole 26 Screw member 27 Screw member 28 Male screw part 29 Male screw part 30 Bolt 31 Bolt 32 Nut 33 Nut 34 Fixing recess 35 Fixing recess 35 36 Projection part of split ring 37 Projection part of split ring 38 Split ring 39 Split ring 40 Step part 41 Step part 42 Seal member 43 Seal member

70 Pipe joint 71 Mountain portion 72 Valley portion 73 Bellows 74 Pipe body 75 Flange portion 76 Covering portion 77 Stretching and absorbing portion 78 Notch portion

Claims (8)

In a pipe joint joined between a plurality of fluid pipes and formed to be stretchable along the axial direction,
It is made of a fluorine-based resin, has an inner peripheral surface that is formed smoothly, and an expansion / contraction tube portion that can be expanded / contracted in the axial direction, and is disposed radially outward of the expansion / contraction tube portion. A bend prevention member formed of an elastic material, and the expansion tube portion is formed in a cylindrical shape as a whole, and a recess provided along the circumferential direction is provided on the outer periphery of the expansion tube portion. A pipe joint , wherein a plurality of the anti-bending members are formed from an annular member made of a rubber material that can be fitted into the concave portion . Disposed radially outwardly of the telescopic tube unit, characterized in that it comprises a radial restriction member capable of restricting the radial expansion of the expansion pipe section, the pipe joint according to claim 1. 3. The pipe joint according to claim 2 , wherein the radial direction regulating member is formed of a plurality of metal ring-shaped members arranged at a predetermined interval along the axial direction of the telescopic pipe portion. The radial direction regulating member is formed of a metal pipe member having a length dimension substantially the same as the axial direction of the telescopic pipe part and having a diameter dimension capable of covering the telescopic pipe part from the outside. The pipe joint according to claim 2 , wherein the pipe joint is provided.   At both ends of the expansion tube portion, pipe joint side flange portions connected to the fluid tube side flange portion provided at the expansion tube side end portion of the fluid pipe are provided, and pipe joints at both ends of the expansion tube portion are provided. 2. The pipe joint according to claim 1, wherein a member for preventing excessive expansion / contraction is provided between the side flanges so as to restrict expansion / contraction of the expansion / contraction tube portion in the axial direction. The excessive expansion and contraction prevention member is formed in an elongated rod shape having a shorter dimension than the axial interval between the pipe joint side flanges at both ends of the expansion tube portion, and screw holes are provided in the axial direction at both ends,
In the screw hole, a screw member is combined through a through hole provided in communication with the fluid pipe side flange portion and the pipe joint side flange portion from the axially outer side of the fluid pipe side flange portion,
The male screw portion of the screw member is formed to have a smaller diameter than the through hole, and has a length larger than the total thickness of the fluid pipe side flange and the pipe joint side flange. Formed,
The excessive expansion and contraction prevention member and the head of the screw member are formed to have a diameter larger than that of the through hole, so that the screw member is slidably attached to the inside of the through hole over a predetermined length. 6. The pipe joint according to claim 5 , wherein the pipe joint is provided. The pipe joint according to any one of claims 1 to 6 , wherein the inner surface of the telescopic pipe part and the inner surface of the fluid pipe body are formed in a smooth state.   The pipe joint according to claim 1, wherein the fluororesin is polytetrafluoroethylene.