JP5085221B2 - Pipe fitting - Google Patents

Description

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

Conventionally, when joining a plurality of fluid pipes with pipe joints, as shown in FIG. 3, a plurality of bends 71 and 72 are used from the viewpoint of absorbing thermal expansion or contraction of the connected fluid pipes in the connecting pipe portion. The pipe joint 70 which combined these was used. The pipe joint 70 moves the bend 71 upward by loosening the flanges 75 and 76 and pushing down the bend 72 without moving the fluid pipes 73 and 74 when exchanging the packings 78 and 79 at both ends. Further, after the bend 71 is removed, the bend 72 can be removed by loosening the flange portion 77.
For this reason, compared with the pipe joint formed in a straight line, there is an advantage that the replacement work of the packings 78 and 79 is easy and the maintainability is good. On the other hand, when the fluid pipe is thermally expanded or contracted, the packings 78 and 79 are provided. However, there was a problem that the packing was deteriorated at an early stage.

In order to solve the above problems, there has been proposed a pipe joint composed of a tubular member that can be expanded and contracted and a bellows portion disposed on the inner surface of the tubular member (Patent Document 1).
As shown in FIG. 4, the pipe joint according to the above document is engaged with the tubular member 81 that is made to be extendable and contracted, the bellows portion 82 provided on the inner surface of the tubular member 81, and the tubular member 81. And a rod-shaped regulating member 83 that regulates the stretched state.
The tubular member 81 has an insertion tube portion 81a having a flange surface 84 formed at one end thereof, and a connection portion 85 configured in the same manner as the insertion tube portion 81a and having an enlarged diameter on the other end side. And a receiving side pipe part 81b into which the insertion pipe part 81a is inserted into the connection part 85.

The tubular member 81 can be connected by inserting the insertion tube portion 81a into the connection portion 85 of the receiving-side tube portion 81b so that the flange surfaces 84 are located at both ends. The length can be expanded and contracted by changing the state. The expandable width is regulated by the interval between the regulation nuts 86 screwed to the one end of the regulation member 83 with a predetermined width across the flange surface 84.
According to the pipe joint according to this patent document, the thermal expansion and contraction of the fluid pipe can be flexibly expanded and contracted, and the load applied to both ends of the pipe joint is reduced. Since the fluid stays in the bellows part and the fluid pool is generated, the cleaning inside the fitting is inferior, and it is difficult to manually remove the bellows from both ends. I had a problem that I could not.
JP-A-7-269759

  Therefore, the technical problem of the present invention is to flexibly expand and contract with respect to the thermal expansion and contraction of the fluid pipe, thereby absorbing the stress change in the axial direction of the fluid pipe by the thermal expansion and thermal contraction, and An object of the present invention is to provide a pipe joint that reduces the load load, facilitates the replacement of packing, and has good internal cleaning properties.

In order to solve the above-mentioned problems, in the invention according to claim 1, a pipe joint joined between a plurality of fluid pipes and capable of expanding and contracting along the axial direction, and an expanding and contracting pipe part extending and contracting in the axial direction And a radial direction restricting member that is disposed outside the telescopic tube part and can regulate expansion of the telescopic tube part in the radial direction, and disposed outside the radial direction restricting member, An axial direction regulating member capable of regulating extension in the axial direction is provided, and the expansion and contraction tube portion is disposed between a pair of tube main body portions disposed at both axial end portions and the tube main body portion. The pair of tube main body portions are made of short cylindrical members each having a flange portion at both ends, and the elastic member is made of a cylindrical member disposed in contact with the inner peripheral surface portion of the pair of tube main body portions. It is characterized by becoming.

Accordingly, the expansion and contraction of the fluid pipe is absorbed by the expansion and contraction tube portion, and the radial restriction member prevents the expansion in the radial direction when the fluid pressure increases. Further, the axial direction regulating member prevents excessive stretching in the axial direction of the expansion / contraction tube portion when the fluid tube contracts, and stress expansion due to expansion / contraction of the fluid tube in the axial direction causes the expansion / contraction tube portion to expand / contract. Is absorbed by.

In the invention according to claim 2, the pipe main body portion includes an outer flange portion at both axial end portions and an inner flange portion formed inward in the axial direction of the outer flange portion. Both ends of the expansion / contraction member are fixed to the pair of outer flange portions, and the radial restriction member is formed to have substantially the same width as the pair of inner flange portions. It is arrange | positioned between inner flange parts, and is joined to the inner flange part via the said spring member.

Accordingly, when the expansion / contraction member expands / contracts due to the expansion / contraction of the fluid pipe in the axial direction, the spring member also expands / contracts together, and when the expansion / contraction state of the fluid pipe returns to the steady state, the expansion / contraction pipe portion is in a steady state by the biasing force of the spring. Return to.

The invention according to claim 3 is characterized in that the telescopic tube portion is formed of a material having rigidity capable of being bent manually.

Accordingly, since the telescopic tube portion can be contracted manually, it becomes easy to remove the pipe joint from the fluid tube at the time of replacing the packing at the joint portion.

The invention according to claim 4 is characterized in that the radial direction regulating member is formed of a plurality of ring-shaped members.

Therefore, the ring-shaped member can regulate the change in stress due to the expansion in the radial direction, and even when the expansion / contraction tube portion expands / contracts in the axial direction, the fluid tube shaft is increased or decreased by increasing / decreasing the gap of each ring. It can absorb changes in stress due to stretching in the direction.

Further, the pipe joint according to the invention of claim 5 is disposed in the gap between the plurality of ring-shaped members, absorbs the expansion / contraction force in the axial direction, and returns the expansion / contraction state of the expansion / contraction pipe part to the steady position. It has the spring member to urge.

Therefore, even when the telescopic tube portion expands and contracts, it automatically returns to a steady state by the urging force of the spring member, and the intervals between the plurality of ring-shaped members are kept even.

According to a sixth aspect of the present invention, the axial direction regulating member is formed in a cylindrical shape, and both end portions engage with the pair of inward flange portions, and are disposed so as to cover the spring member. It is characterized by being.

Therefore, even when the spring member is extended due to contraction of the fluid pipe, both ends of the axial direction regulating member are engaged with the inward flange portion, so that the elastic member is excessively extended. Is prevented.

In the invention according to claim 7, the axial restriction member is provided with a fluid leakage detection hole penetrating in the radial direction in order to detect fluid leakage when the telescopic tube portion is damaged. It is characterized by.

Therefore, even if the expansion / contraction member is broken, the breakage of the expansion / contraction tube portion is detected by leakage of the fluid in the fluid tube from the detection hole.

The invention according to claim 8 is characterized in that the radial direction regulating member is made of an incompressible liquid sealed between the axial direction regulating member and the telescopic tube portion.

Therefore, even when the expansion / contraction pipe part receives a radially outward stress due to the fluid pressure inside the fluid pipe, the volume change of the incompressible liquid is extremely small. It is possible to prevent expansion deformation outward in the direction.

In the invention according to claim 9, a cylindrical axial direction regulating member is engaged and fixed to the pair of inner flange portions, and the telescopic tube portion, the pair of inner flange portions, and the axial direction. The incompressible liquid is sealed in a gap defined by the regulating member.

Therefore, even when the telescopic tube portion is subjected to radial outward stress due to the fluid pressure inside the fluid tube, the volume change of the incompressible liquid enclosed in the gap is extremely small. It is possible to prevent the expansion tube portion from being expanded and deformed radially outward.

The invention according to claim 10 is characterized in that the incompressible liquid is silicone oil.

The invention according to claim 11 is characterized in that the rigid material constituting the expansion tube portion is a rubber material.

The invention according to claim 12 is characterized in that the inner surface of the telescopic tube portion and the inner surface of the fluid tube are formed in a smooth state.

Therefore, there are no gaps or steps in the connecting portion between the telescopic tube portion and the joint portion, and the connecting portion between the joint portion and the fluid pipe, and the fluid flow is obstructed by the gap or step portion, so that no retention occurs.

In the inventions according to claims 1 to 12, since the expansion and contraction tube portion can be contracted flexibly in the axial direction even when thermal expansion occurs in the fluid tube, the fluid tube is caused by thermal expansion. The load generated at the connecting part can be absorbed quickly. For this reason, the load applied to the connection portion is reduced, and deterioration of the packing is prevented.

  Further, since the expansion and contraction tube is prevented from expanding in the radial direction by the radial direction regulating member, the expansion and contraction tube portion can be prevented from being excessively expanded and damaged even when the fluid pressure is increased. Furthermore, excessive stretching not only in the radial direction but also in the axial direction of the expansion / contraction tube portion is restricted, so that the expansion / contraction tube portion is prevented from being damaged and a pipe joint having higher durability can be provided.
  Also, because no bellows is used, fluid stays in the bellows part, fluid pooling occurs, the cleaning property is inferior, and it is difficult to remove the bellows, making it difficult to replace the packing. Can be avoided.

In addition, in the invention of claim 3, in addition to the above effects, it is possible to bend the telescopic tube part manually, so even when removing the pipe joint for packing replacement work, There is no need to move the fluid pipe body. Therefore, the efficiency of packing replacement work is improved.

In addition, in addition to the above-described effect, the ring-shaped member can regulate the stress change of the expansion tube portion in addition to the above effect.

Further, in the invention according to claim 7, even when the expansion / contraction tube part is broken, the pipe joint can be replaced quickly because the pipe is quickly detected by the leakage of the fluid from the detection hole. Line safety is improved.

Further, in the inventions according to claims 8 to 10, in addition to the above effect, the radial regulating member is an incompressible liquid, and therefore, the fluid pressure inside the telescopic tube portion is increased or decreased. However, since the volume change of the incompressible liquid which is the radial direction regulating member is extremely small, it is possible to prevent the damage caused by the expansion or contraction of the expansion tube portion.

In addition to the above effect, the invention according to claim 12 is characterized in that the inner surface of the telescopic tube portion and the inner surface of the fluid tube are formed in a smooth state, and therefore the connection between the telescopic tube portion and the joint portion. Due to the gap between the portion and the connection portion between the joint portion and the fluid pipe, the flow of the fluid is prevented from being blocked and retained, and a pipe joint with good cleaning properties can be provided.

  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 ring-shaped members.

  As shown in FIG. 1, the pipe joint 10 is connected to the fluid pipes 11 and 12 via packings 30 and 31, and is an expandable pipe part formed of a rubber material having rigidity that can be bent manually. 15 and joint portions 13 and 14.

The telescopic tube portion 15 includes a pair of tube main body portions 16 and 17 disposed at both ends in the axial direction, and a telescopic member 18 disposed between the tube main body portions 16 and 17, and the pair of tube main portions. The main body parts 16 and 17 are short cylinders having outer flange parts 19 and 21 and inner flange parts 20 and 22 formed axially inward of the outer flange parts 19 and 21 at both axial ends. The elastic member 18 is composed of a cylindrical member disposed in contact with the inner peripheral surface portion 23 of the pair of tube main body portions 16 and 17.
Both ends 24 and 25 of the elastic member 18 are fixed to the outer flange portions 19 and 21 of the pipe main body portions 16 and 17.

A radially restricting member 26 made of a plurality of ring-shaped members formed to have substantially the same dimensions as the inner flange portions 20 and 22 of the tube main body portion is arranged in parallel in the axial direction outside the telescopic tube portion 15. Yes.
Each ring-shaped member of the radial direction regulating member 26 is connected to each other between the ring-shaped members and the inner flange portions 20 and 22 via a spring member 27.
Outside the radial direction regulating member 26, an axial direction regulating member 28 that is formed in a cylindrical shape, has both end portions engaged with the inner flange portions 20 and 22, and covers the spring member 27. ing.
The axial direction regulating member 28 is provided with a fluid leakage detection hole 29 penetrating in the radial direction in order to detect fluid leakage when the telescopic tube portion 15 is broken.
The inner surfaces reaching the fluid pipe 11, the pipe joint 10, and the fluid pipe 12 are joined in a state of forming the same surface.

Embodiments having the above-described configuration will be described with reference to the drawings.
As shown in FIG. 1, a predetermined liquid product flows inside the fluid pipe 11, the pipe joint 10, and the fluid pipe 12. When the fluid pipes 11 and 12 are expanded in the axial direction due to a rise in the temperature of the liquid or the outside air temperature, the pipe joint 10 is subjected to a load that contracts in the axial direction. It is transmitted to the telescopic tube portion 15 via the portion 13.
In the telescopic tube portion 15, the tube main body portions 16 and 17 are pressed inward in the axial direction by the load. However, the telescopic member 18 is absorbed by contraction.
Therefore, a large load is applied to the packings 30 and 31 sandwiched between the joint portions 13 and 14 and the fluid pipes 11 and 12, and deterioration of the packings 30 and 31 is prevented.

  Further, when the liquid pressure inside the fluid pipes 11 and 12 increases, an expansion force in the radial direction is generated in the expansion / contraction member 18, but outward in the radial direction of the expansion / contraction tube portion 15 by the radial direction regulating member 26. Is prevented, and the expansion tube portion 15 is prevented from being damaged.

When the fluid pipes 11 and 12 are contracted in the axial direction due to a decrease in the temperature of the liquid or the outside air temperature, the pipe joint 10 is subjected to a load extending in the axial direction.
Also in the above case, similarly to the contraction load, it is transmitted to the expansion / contraction tube section 15 through the joint section 13 and absorbed by the expansion / contraction member 18 extending.
At this time, the tube main body portions 16 and 17 move outward in the axial direction in conjunction with the extension of the telescopic tube portion 15, but the inner flange portions 20 and 22 are engaged with the axial direction regulating member 28. Therefore, the expansion tube portion is prevented from being stretched beyond the axial dimension of the axial direction regulating member 28, and the expansion tube portion 15 is prevented from being damaged due to stretching.

  In addition, when the expansion tube portion 15 is damaged, the internal liquid leaks from the damaged portion, but the leaked liquid flows out from the fluid leak detection hole 29, so that the damage is quickly found, and replacement, repair, etc. Prompt response is possible.

  When the packings 30 and 31 are exchanged, the connecting portions between the joint portions 13 and 14 and the fluid pipes 11 and 12 are loosened, and the expansion and contraction pipe portion 15 is bent manually, so that the fluid pipes 11 and 12 are axially moved. Even if it does not move outward, the pipe joint 10 can be easily removed. Therefore, the efficiency of the packing replacement work is improved, and the maintenance is very good.

  Further, the inner surfaces of the paths leading to the fluid pipe 11, the pipe joint 10, and the fluid pipe 12 are joined in a smooth state, so that there is no unevenness on the inner surface of the joined portion, and the liquid flows into the joined portion. Since there is no stagnation, it is possible to provide a pipe joint with good cleanability.

An embodiment in which the radial direction regulating member is formed of silicon oil which is an incompressible liquid will be described below with reference to the drawings.
As shown in FIG. 2, a cylindrical axial regulating member 28 is engaged and fixed to the pair of inner flange portions 20 and 22 of the pipe main body portions 16 and 17, and the telescopic tube portion 15 and the pair of inner flanges are connected. A radial direction regulating member 26 made of silicon oil 32 is enclosed in a gap defined by the portions 20 and 22 and the axial direction regulating member 28.
The two end engaging portions of the pair of inner flange portions 20 and 22 and the axial regulating member 28 are sealed by seal members 33 and 34 so that the silicon oil 32 does not leak to the outside. Silicon oil is injected from the injection hole 35.
In FIG. 2, the same components as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

As shown in FIG. 2, when the fluid pipes 11, 12 and the inside of the pipe joint 10 are in a negative pressure state due to a decrease in the liquid flow rate inside the fluid pipes 11, 12, the expansion pipe portion 15 has a direction indicated by an arrow A in the figure. The external pressure acts in the direction in which the gap is enlarged.
Even in the above case, since the volume change of the silicon oil 32 has a very small property, a resistance force against the external pressure works, and the expansion and contraction tube portion 15 contracts radially inward and breaks. Is prevented.
Further, even when the expansion force in the direction opposite to the arrow A in FIG. 2 acts on the telescopic tube portion 15 due to an increase in the liquid flow rate, the same effect as described above can be obtained.

  In Example 1 and other examples, the pipe joint 10 has a structure in which joints 13 and 14 are provided at both ends of the expansion and contraction tube 15, but the joints 13 and 14 are omitted. Even if the outer flange portions 19 and 21 of the tube main body portions 16 and 17 of the telescopic tube 15 are directly connected to the fluid tubes 11 and 12, it is possible to obtain the same operational effects as those of the above embodiments. It is.

  The present invention is applicable to a pipe joint for connecting 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 pipe joint concerning other examples of the present invention. It is an axial sectional view of a conventional pipe joint in which a plurality of bends are combined. 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 Joint part 14 Joint part 15 Telescopic pipe part 16 Pipe main body part 17 Pipe main body part 18 Telescopic member 19 Outer flange part 20 Inner flange part 21 Outer flange part 22 Inner flange part 23 End portion 25 of the tube main body 24 End portion 25 of the expansion / contraction member 18 End portion 26 of the expansion / contraction member 18 Radial direction regulating member 27 Spring member 28 Axial direction regulating member 29 Fluid leak detection hole 30 Packing 31 Packing 32 Silicon oil 33 Sealing member 34 Seal member 35 Silicon oil injection hole

Claims (12)

A pipe joint which is joined between a plurality of fluid pipes and can be expanded and contracted along the axial direction, and an expansion and contraction pipe part which expands and contracts in the axial direction, and is disposed outside the expansion and contraction pipe part. A radial regulating member capable of regulating the expansion of
An axial direction regulating member that is disposed outside the radial direction regulating member and can regulate the extension of the telescopic tube portion in the axial direction,
The telescopic tube portion includes a pair of tube main body portions disposed at both axial end portions, and a telescopic member disposed between the tube main body portions, and the pair of tube main body portions are respectively flanged at both end portions. A pipe joint comprising: a short cylindrical member having a portion, wherein the expansion / contraction member is formed of a cylindrical member disposed in contact with the inner peripheral surface portions of the pair of pipe main body portions. The pipe main body has an outer flange on both axial ends and an inner flange formed on the inner side in the axial direction of the outer flange. And the radial restricting member is formed to have substantially the same width as the pair of inner flange portions and is disposed between the pair of inner flange portions, and the spring. The pipe joint according to claim 1, wherein the pipe joint is joined to the inner flange portion via a member. 2. The pipe joint according to claim 1, wherein the telescopic pipe portion is formed of a material having rigidity capable of being bent manually. 2. The pipe joint according to claim 1, wherein the radial direction regulating member is formed of a plurality of ring-shaped members having rigidity capable of regulating a stress change of the expansion and contraction pipe portion. The spring member is disposed in a gap between the plurality of ring-shaped members and absorbs an expansion / contraction force in the axial direction and biases the expansion / contraction tube portion in a direction to return the expansion / contraction state to a steady position. 4. The pipe joint according to 4. 2. The pipe joint according to claim 1, wherein the axial direction regulating member is formed in a cylindrical shape, and both end portions engage with the pair of inward flange portions and are disposed so as to cover the spring member. . 2. The pipe joint according to claim 1, wherein the axial direction regulating member is provided with a fluid leakage detection hole penetrating in a radial direction in order to detect a fluid leakage when the expansion tube portion is broken. . 2. The pipe joint according to claim 1, wherein the radial direction regulating member is made of an incompressible liquid sealed between the axial direction regulating member and the telescopic pipe portion. A cylindrical axial restriction member is engaged and fixed to the pair of inner flange portions, and a gap defined by the telescopic tube portion, the pair of inner flange portions, and the axial restriction member is formed in the gap. The pipe joint according to claim 2, wherein the incompressible liquid composition is sealed. The pipe joint according to claim 9, wherein the incompressible liquid is silicone oil. 2. The pipe joint according to claim 1, wherein the material having rigidity constituting the expansion tube portion is a rubber material. The pipe joint according to claim 1, wherein the inner surface of the expansion tube portion and the inner surface of the fluid tube are formed in a smooth state.