JPH05231573A - Sealing device of tube connection part - Google Patents

Abstract

PURPOSE:To maintain high sealing performance by deforming the circumferential intermediate part of a thin plate ring in the direction of the plate thickness under a tightened condition of a pair of tube bodies and whereby generating spring force on the thin plate ring. CONSTITUTION:When a pair of tube bodies 7, 8 are tightened up by fitting a sealing ring 10 into an annular groove 6, an intermediate part 11B of a ceramic thin plate ring 11 is pressed by an annular intermediate plate 13, and the ring is bent and is thus deformed in the axial direction. As a result, spring force for forcing the thin plate ring 11 to return to the flat plate is generated. An end surface 8A of the tube body 8 is pressed by the intermediate part 11B of the thin plate ring 11 by the spring force, while a bottom surface 6A of the annular groove 6 is pressed by an inside part 11A as well as an outside part 11C, surface pressure is generated on the end surface 8A of the tube body 8 and on the bottom surface 6A of the annular 5 groove 6. High sealing performance can thus be maintained under a using condition of high temperature and high heat load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for a pipe connecting portion for connecting pipes for flowing fluid such as an exhaust manifold, a turbocharger and an exhaust pipe to each other.

[0002]

2. Description of the Related Art Generally, in an engine for an automobile, exhaust gas emitted from the engine is discharged into the atmosphere through an exhaust pipe, but an exhaust manifold, an exhaust pipe, and exhaust energy are provided in the middle of an exhaust system. A turbocharger equipped with a turbine driven by, a catalytic converter for detoxifying harmful substances such as carbon monoxide and nitrogen oxides contained in exhaust gas, an afterburner for burning hydrocarbons, and exhaust gas A silencer or the like for attenuating noise is provided. A seal ring is provided at a pipe connecting portion that connects the pipes for flowing fluids such as the exhaust manifold and the exhaust pipe to each other so as to maintain airtightness in the pipe connecting portion.

Conventionally, as a seal ring applied to such a pipe connecting portion, there is one disclosed in Japanese Utility Model Publication No. 2-9374. As shown in FIG. 9, the seal ring 36 includes a hollow ring 37 formed by rolling a ring-shaped thin metal plate into an annular shape having a circular cross section, and a gasket material containing a non-heat-resistant substance filled in the hollow ring 37. And 38.

Then, as shown in FIGS. 7 and 8, the surface of the flange 34 of one pipe 32 is formed into a flat surface, and the other pipe 3 is formed.
1. An annular groove 35 is formed on the surface of the flange 33 of No. 1, and the annular groove 3
5, a part of the seal ring 36 is fitted in a state of protruding from the annular groove 35, and in this state, the flanges 33 and 34 of the two pipes 31 and 32 are aligned with each other and tightened by using a bolt and a nut. The pipes 31 and 32 are connected to each other while maintaining airtightness. At this time, the seal ring is elastically compressed between both flanges and pushed into the annular groove, and both flange surfaces are in close contact with each other. In this state, the airtightness of both flanges is determined by the annular groove formed in the flange. The spring action of the seal ring that is about to protrude causes the seal ring to be maintained by being strongly pressed against the flange surface.

However, the pipe connecting portion connecting the outlet pipe of the exhaust manifold and the inlet pipe of the turbocharger has a high temperature (for example, 750 ° C. or higher) in use, and is used for the pipe connecting portion at the high temperature portion. The seal ring will be exposed to high temperatures. Therefore, when the conventional seal ring is used, the gasket material filled in the metal seal ring is thermally decomposed by the organic component of the binder contained in the gasket material, or thermally decomposed. There is a phenomenon that the volume of the gasket material decreases with the scattering. When the seal ring filled with the gasket material as described above is sandwiched between the flange surfaces of both pipes and connected with bolts and nuts, the gasket material is subjected to heat load as described above and the volume of the gasket material decreases. As a result, the elastic compression force of the seal ring becomes small, and the sealing property of the contact surface of the pipe connecting portion deteriorates.

Further, regarding a pipe connecting portion in which a seal ring filled with a gasket material is sandwiched between flange faces of both pipes and connected by a bolt and a nut, the flange face of the pipe connecting portion is repeatedly used at high temperature and room temperature. When subjected to the heat load, the both flange surfaces are distorted, the flange surfaces are deformed, and the seal ring cannot be satisfactorily abutted, so that the sealing performance of the pipe connecting portion is further deteriorated.

Further, Japanese Patent Publication No. 62-2188 discloses that
A seal member used for joining exhaust turbocharger flanges is disclosed. The seal member includes a filler,
And a metal jacket having a hollow ring shape enclosing the filling material and having joints at both ends along the ring circumferential direction. The metal jacket is doubled or tripled, and the joints at both ends are offset from each other. By shifting the seams of the metal jackets from each other, this sealing member can considerably prevent the medium or air to be sealed from entering through the gaps between the metal jackets. This is not a perfect seal member to be used in the above, and in the end, the problem that the filler is deteriorated due to oxidation or the like and the sealing property is deteriorated is not completely solved.

[0008]

SUMMARY OF THE INVENTION As mentioned above, the above-mentioned Japanese Utility Model Publication No. 2-9374 or Japanese Patent Publication No. 62-218.
Both of the conventional seal rings disclosed in Japanese Patent Publication No. 8 have a fundamental problem in that they use a material that may be deteriorated due to high temperature and large heat load.

Therefore, it is conceivable to make a seal ring by using a heat-resistant material which is not affected by heat, for example, ceramic, without using any gasket material containing an organic component which is easily affected by heat as in the prior art. However, at that time, it is necessary to provide a heat-resistant seal ring with a function as a spring so as to cope with a heat load. Therefore, it is conceivable to process the seal ring itself into, for example, a disc spring shape in order to give the seal ring a function as a spring. However, it is considerably difficult to process the heat-resistant material into such a special shape with high accuracy and the manufacturing cost is increased. On the other hand, it is easy and cost-effective to process the seal ring into a flat plate shape, but the flat plate seal ring itself does not generate a spring action, and therefore cannot handle a heat load. Therefore, in this case, how to give the flat plate-shaped seal ring a function as a spring is a problem.

An object of the present invention is to solve the above-mentioned problems, and a seal ring arranged between pipes is a flat plate-shaped heat-resistant and elastic thin plate ring, and the thin plate ring is arranged in the plate thickness direction. By using the pressing means that deforms to generate the spring force, it can be easily manufactured without requiring high processing accuracy, and moreover, a plurality of sets (a plurality of sets) of thin plate rings and pressing means are stacked. An object of the present invention is to provide a sealing device for a pipe connecting portion which can be controlled to an appropriate compression amount by combining and can maintain a high sealing property even under a use condition of high temperature and large heat load.

[0011]

In order to achieve the above object, the present invention is configured as follows. That is,
The present invention relates to a sealing device for a pipe connecting portion, which includes a pair of pipes having surfaces facing each other and tightened with each other, and a seal ring arranged between the pipes facing each other. A thin plate ring having heat resistance and elasticity, and an edge part of the thin plate ring is held, and the circumferential middle portion of the thin plate ring is deformed in the plate thickness direction in a tightened state of the pair of pipe bodies. The present invention relates to a sealing device for a pipe connecting portion, which has a pressing means for generating a spring force on the ring.

Further, in the sealing device for the pipe connecting portion,
The pressing means is a metal hugging thin plate ring, and is arranged concentrically between the hugging thin plate ring and the thin plate ring, and the thin plate is between the hugging thin plate ring and the thin plate ring. A ring-shaped intermediate plate that forms a gap that can deform the ring, and the holding thin plate ring has a holding portion in which the inner and outer portions holding the inner and outer portions of the thin plate ring are respectively bent. .

Further, in the sealing device for the pipe connecting portion,
The pressing means comprises a first holding thin plate ring that holds the inner portion of the thin plate ring on the inner side and a second holding thin plate ring that holds the outer side of the thin plate ring on the outer side,
An outer portion of the first holding thin plate ring and an inner portion of the second holding thin plate ring are overlapped at an intermediate portion to form a superposed portion having different thicknesses.

Further, in the sealing device for the pipe connecting portion,
The thin plate ring is composed of a first thin plate ring and a second thin plate ring arranged concentrically opposite to each other, and the pressing means is a ring arranged concentrically between the first thin plate ring and the second thin plate ring. -Shaped intermediate plate, a first holding thin plate ring that holds the inner portions of the first thin plate ring and the second thin plate ring together, and the outer portions of the first thin plate ring and the second thin plate ring together It is composed of a second holding thin plate ring to be held.

Further, in the sealing device for the pipe connecting portion,
The intermediate plate is joined to the thin plate ring by adhesion, welding, or the like. The thin plate ring is preferably made of ceramics or a metal such as heat-resistant alloy steel. The thin plate ring may be a single ring or may be composed of a plurality of rings.

Further, the sealing device for the pipe connecting portion is constructed by stacking a plurality of sets of assemblies each consisting of the thin plate ring and the pressing means.

[0017]

The sealing device for the pipe connecting portion according to the present invention is constructed as described above and operates as follows. That is, in general, a heat-resistant spring ring such as a ceramic spring ring has poor workability, but the heat-resistant and elastic thin plate ring that constitutes the seal ring of the present invention has a flat plate-like extremely simple shape. It can be easily manufactured without requiring high processing accuracy. In the state where the thin plate ring of the seal ring incorporated in the sealing device for the pipe connecting portion is tightened between the pair of pipe bodies, the intermediate portion of the thin plate ring is deformed in the plate thickness direction by the action of the pressing means to generate the spring force. To do. That is, in the tightened state, the thin plate ring has a force to return to the state of the flat plate before the deformation, so that the outer side portion, the inner side portion and the intermediate portion press the sealing surface. In this way, the inner, outer, and middle parts of the seal ring are strongly pressed against the opposing seal surfaces of the tubular body by the spring force of the thin plate ring, so the seal surfaces are always in close contact even if a large heat load is applied. Therefore, high sealing performance can be maintained.

Further, regarding the sealing device for the pipe connection,
Since a plurality of sets of the assembly including the thin plate ring and the pressing means are superposed on each other, the amount of compression, that is, the amount of bending can be appropriately increased according to the state of the pipe connecting portion. That is, the compression amount is small when one set of the assembly including the thin plate ring and the pressing means is used, but the compression amount can be increased when the plurality of sets of the assembly are stacked. Can be properly controlled.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a sealing device for a pipe connecting portion according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing an example of an exhaust manifold incorporating a sealing device for a pipe connection portion according to the present invention, and FIG. 2 is a side view as seen from the line AA side in FIG.

As shown in FIGS. 1 and 2, the exhaust manifold 1 is attached to the cylinder head of an in-line 6-cylinder engine. The exhaust manifold 1 includes mounting flange portions 2A and 2B that are mounted on the cylinder head. The exhaust manifold 1 is composed of a first exhaust manifold 1A and a second exhaust manifold 1B each having three mounting flange portions 2A and 2B corresponding to three cylinders. First exhaust manifold 1A and second exhaust manifold 1B
Are connected by a flexible joint 4 made of a bellows. Further, the first exhaust manifold 1A and the second exhaust manifold 1B
Respectively have outlet pipes 3A and 3B which are collecting pipes. These outlet pipes 3A and 3B are connected to inlet portions 5A and 5B of a turbocharger provided downstream of the engine by tightening bolts and nuts.
In such a configuration, the exhaust gas discharged from the engine passes through the exhaust ports of the cylinders and the mounting flange portions 2
It is collected in outlet pipes 3A and 3B through respective branch passages formed in the central portions of A and 2B, and then fed into the turbocharger through inlets 5A and 5B of the turbocharger.

The sealing device for the pipe connecting portion according to the present invention is incorporated in the pipe connecting portion between the collecting pipes of the exhaust manifold 1, that is, the outlet pipes 3A, 3B and the inlet pipes 5A, 5B of the turbocharger. At the ends of the outlet pipes 3A, 3B of the exhaust manifold 1, pipe bodies 7 each having a flange with a flat end surface 9 are provided, and also the inlet pipes 5A, 5B of the turbocharger.
Each of the ends is provided with a tube body 8 having a flange whose end face 23 is flat. Exhaust manifold 1 outlet pipe 3
An annular groove 6 is formed in each of the tube bodies 7 at the end portions of A and 3B on the facing surface facing the respective tube bodies 8 of the inlet pipes 5A and 5B of the turbocharger. A seal ring 10 is incorporated in these annular grooves 6.

FIG. 3 is a sectional view showing an embodiment of a sealing device for a pipe connecting portion according to the present invention. The seal ring 10 in this sealing device includes a ceramic thin plate ring 11 serving as a thin plate ring having excellent heat resistance and elasticity, a metal thin plate ring 12 serving as a pressing metal holding thin plate ring, and a ring-shaped intermediate plate. It is composed of an assembly consisting of 13 and 13.

The ceramic thin plate ring 11 has a flat plate shape in a natural state where no load is applied. The thin metal plate ring 12 has a flat portion 12A, a first holding portion 12B formed on the inner side portion, and a second holding portion 12C formed on the outer side portion. The ring-shaped intermediate plate 13 is a ceramic thin plate ring 11.
Is a size having an intermediate diameter.

The ceramic thin plate ring 11 and the ring-shaped intermediate plate 13 are concentrically overlapped with each other and their flat surfaces are adhered to each other. The thin plate ring 11 made of ceramic and the thin plate ring 12 made of metal are arranged concentrically so as to sandwich the ring-shaped intermediate plate 13, and the first holding portion 12B of the thin plate ring 12 made of metal forms a thin plate ring made of ceramic. The inner side portion 11A of 11 is held, and the second holding portion 12C holds the ceramic thin plate ring 1
1 is holding the outer portion 11C. This seal ring 1
Regarding 0, for example, the ceramic thin plate ring 11 is 0.2 mm, the metal thin plate ring 2 is 0.2 mm, and the ring-shaped intermediate plate 13 is 0.3 mm. Therefore, the thickness of the inner and outer portions of the seal ring 10 is 0.9 mm, and the thickness of the middle portion is 0.7 mm. In addition, the ceramic thin plate ring 11 and the metal thin plate ring 1 in the inner and outer parts
A gap of 0.3 mm is formed between the two.

FIG. 3 shows the seal ring 10 in its natural state with no load applied. This seal ring 10
1 is applied to the exhaust manifold shown in FIG. 1, the seal ring 10 has, for example, an outer diameter of 60 mm and an inner diameter of 50 mm. The seal ring 10 is fitted into the annular groove 6 so that the pipe body 7 and the inlet pipe 5 at the end portions of the outlet pipes 3A and 3B are inserted.
When the tubes 8 at the ends of A and 5B are tightened with bolts and nuts, the state shown in FIG. 4 is obtained. That is, the seal ring, which was in a state of protruding from the annular groove 6 before the tightening, receives a pressing force from the bottom surface 6A of the annular groove 6 and the end surface 8A of the tube body 8 in the tightening state, so that the first holding The portion 12B and the second holding portion 12C are deformed. On the other hand, since the ring-shaped intermediate plate 13 is arranged in the intermediate portion of the seal ring 10, the ceramic spring ring 11 is deformed so that the intermediate diameter portion 11B is pressed by the ring-shaped intermediate plate 13 and is recessed into a ring shape. Then, it is pressed against the bottom surface 6A of the annular groove 6.

By tightening both pipes 7 and 8 in this manner, the ceramic thin plate ring 11 is deformed in the thickness direction so that both sides of the intermediate portion 11B are bent, so that the ceramic thin plate ring 11 has a flat plate shape. The force to return to is generated. And by the force to return to this flat plate shape,
The intermediate portion 11B of the ceramic thin plate ring 11 presses the end surface 8A of the tubular body 8, and surface pressure is generated on the end surface 8A as shown in FIG. Further, the inner side portion 11A and the outer side portion 11C of the ceramic thin plate ring 11 press the bottom surface 6A of the annular groove 6, and surface pressure is generated on the bottom surface 6A as indicated by reference characters IES, CS and OES in FIG. In this way, the seal ring 1
With 0, the inner part, the outer part, and the middle part are brought into close contact with each other due to the spring action of the ceramic spring ring 11, so that good sealing performance can be maintained even if a large distortion occurs on the sealing surface due to heat load. it can. Moreover, although not shown, the seal ring 10 is composed of an assembly of a thin plate ring 11, a metal thin plate ring 12 and a ring-shaped intermediate plate 13, and a plurality of sets of the assembly are superposed to compress or flex You can also control the amount to a proper value.

FIG. 5 is a sectional view showing another embodiment of the sealing device for a pipe connecting portion according to the present invention. The seal ring 10 in the sealing device for the pipe connecting portion includes a ceramic thin plate ring 14 as a thin plate ring having high heat resistance and elasticity, and a first metal thin plate ring 15 and a second metal thin plate ring 16 as pressing means. It consists of an assembly consisting of and. Also in this embodiment, as in the above-described embodiment, the sealing device can be configured by stacking the assemblies. The first metal thin plate ring 15 has a holding portion 15A for holding the inner portion of the ceramic thin plate ring 14 on the inner side.
The second metal thin plate ring 16 has a holding portion 16A that holds the outer portion of the ceramic thin plate ring 14 on the outer side. The outer portion 15B of the first metal thin plate ring 15 and the inner portion 16B of the second metal thin plate ring 16 are overlapped with each other to form a superposed portion 17 having a different thickness in the middle portion of the seal ring 10.

The thickness of the ceramic thin plate ring 14 is, for example, 0.2 mm, and the thickness of the first metal thin plate ring 15 and the second metal thin plate ring 16 is, for example, 0.2 mm. Therefore, the thickness of the inner and outer parts of the seal ring 10 is 0.6 mm, and the thickness of the middle part is also 0.6 mm. It is biased.

The seal ring 10 is fitted in the annular groove 6, and the pipe body 7 and the inlet pipes 5A, 5 at the ends of the outlet pipes 3A, 3B.
The pipe flange 8 at the end of B is tightened with bolts and nuts to be attached to the pipe connecting portion. At that time, the inner portion 14A and the outer portion 14C of the ceramic thin plate ring 14 receive a pressing force from the bottom surface 6A of the annular groove 6, and the overlapping portion 17 of the intermediate portion 14B receives a pressing force from the end surface 8A of the tubular body 8. Then, the intermediate portion 14B of the ceramic thin plate ring 14 is deformed in the plate thickness direction so that it can be bent and is pressed against the bottom surface 6A of the annular groove 6. Since the ceramic thin plate ring 14 having the deformed intermediate portion 14B generates a spring force that tends to return to a flat plate shape, the bottom surface 6A of the annular groove 6 receives a pressing force at the inner and outer portions thereof and the end surface 8 of the tubular body 8
A receives a pressing force at the intermediate portion. In this way, the inner portion, the outer portion, and the intermediate portion of the seal ring 10 are brought into close contact with the seal surface by the spring action of the ceramic thin plate ring 14, so that the seal surface is sealed even if a large strain is generated by the heat load. It is possible to maintain the goodness.

FIG. 6 is a sectional view showing still another embodiment of the sealing device for a pipe connecting portion according to the present invention. The seal ring 10 in the sealing device for the pipe connecting portion includes a first ceramic thin plate ring 18 and a second ceramic thin plate ring 19 as thin plate rings having excellent heat resistance and elasticity, and a ring-shaped intermediate plate 20 as pressing means. , A first metal thin plate ring 21 and a second metal thin plate ring 22. Also in this embodiment, as in the above-described embodiment, the sealing device can be configured by stacking the assemblies. The first ceramic thin plate ring 18 and the second ceramic thin plate ring 19 have substantially the same dimensions and are arranged to face each other. The ring-shaped intermediate plate 20 is adhered to the first ceramic thin plate ring 18 and further sandwiched between the second ceramic thin plate ring 19. In the sandwiched state, the ring-shaped intermediate plate 20 is arranged in the intermediate portion between the first ceramic thin plate ring 18 and the second ceramic thin plate ring 19. First metal thin plate ring 21
Holds the inner portions of the first ceramic thin plate ring 18 and the second ceramic thin plate ring 19 together in the holding portion 21A. The second metal thin plate ring 22 holds the outer portions of the first ceramic thin plate ring 18 and the second ceramic thin plate ring 19 together in the holding portion 22A.

The thickness of the first ceramic thin plate ring 18 and the second ceramic thin plate ring 19 is, for example, 0.2.
mm, the thickness of the ring-shaped intermediate plate 20 is 0.3 m, for example.
The thicknesses of m, the first metal thin plate ring 21 and the second metal thin plate ring 22 are, for example, 0.2 mm. Therefore,
The seal ring 10 has a thickness of 1.1 mm on the inner side and the outer side and a thickness of 0.7 mm on the middle side.

The seal ring 10 is fitted in the annular groove 6, and the tube body 7 and the inlet tubes 5A, 5 at the ends of the outlet tubes 3A, 3B.
The tube body 8 at the end of B is tightened with bolts and nuts to be attached to the tube connecting portion. At this time, the inner and outer portions of the ceramic thin plate rings 18 and 19 receive a pressing force from the bottom surface 6A of the annular groove 6 and the end surface 8A of the tubular body 8 so that the first ceramic thin plate ring 18 is an intermediate portion. The second ceramic thin plate ring 19 is deformed so as to be bent upward, and is deformed so as to be bent downward at an intermediate portion. Then, the deformed first ceramic thin plate ring 18 and second ceramic thin plate ring 19 generate a spring force to return to the flat plate state. Therefore, the inner and outer portions of the first ceramic thin plate ring 18 press the end surface 8A of the tube body 8 to generate surface pressure on the end surface 8A of the tube body 8. Further, the inner and outer portions of the second ceramic thin plate ring 19 press the bottom surface 6A of the annular groove 6 to generate surface pressure on the bottom surface 6A of the annular groove 6. In this way, the seal ring 10 has a state in which the inner and outer parts are in close contact with each other due to the spring action of the ceramic thin plate rings 18 and 19, so that the sealability is good even if a large distortion occurs in the seal surface due to the heat load. Can be maintained at.

Although not shown in the drawings, a plurality of ceramic thin plate rings may be stacked and used in any of the above embodiments. Alternatively, it goes without saying that a ring-shaped intermediate plate may be interposed between the ceramic thin plate rings that are adjacent to each other. In this way, the spring characteristics can be changed by alternately stacking the plurality of thin plate rings and the plurality of intermediate plates. Alternatively, although not shown, it is also possible to select the above-mentioned assemblies from each other and superimpose a plurality of sets, and the compression force can be appropriately controlled according to the state of the pipe connection portion.

In each of the above embodiments, the case where the plate thickness of the ceramic thin plate ring and the metal thin plate ring is 0.2 mm has been described, but the plate thickness range of the ceramic spring ring 11 is 0. The range of 1 to 0.5 mm and the thickness of the metal thin plate ring is 0.2 to 0.5 mm.
The degree is suitable.

In each of the above embodiments, ceramics is used as the material of the thin plate ring 12, but heat-resistant alloy steel and tool steel (SKD, S
A heat resistant material such as KH), stainless steel (SUS630), nickel alloy Inconel steel, high nickel steel, and Herons alloy steel (HA214) may be used. Also,
The metal thin plate ring can be manufactured by using a metal material that has good workability and is inexpensive. For example, as a material,
SPC, SUS304, copper, aluminum, SUS31
0S and the like are preferable. The material of the ring-shaped intermediate plate is SP
C, copper, aluminum, SUS304, ceramics and the like are suitable.

Further, in the sealing device for the pipe connecting portion, good sealing performance can be always ensured by appropriately selecting the number of heat-resistant spring rings or the material thereof as described above.

[0037]

The sealing device for the pipe connecting portion according to the present invention comprises:
Since it is configured as described above, it has the following effects. That is, in general, heat-resistant materials such as ceramics have poor workability, but the thin plate ring used in the sealing device for the pipe connection portion according to the present invention is simply processed into a simple shape such as a flat plate-shaped ring, so that the accuracy is simple. It can be processed well. On the other hand, the pressing means for deforming the middle part of the thin plate ring into a bent state in the plate thickness direction and pressing it against the sealing surface is made by using a low-priced material excellent in workability. It can be easily processed. As described above, the sealing device for the pipe connection portion has an extremely simple structure, can be easily manufactured at low cost, and can provide a structure having an extremely high sealing property.

Further, when the flat plate-shaped thin plate ring is fitted into the annular groove and the pair of pipes are tightened, the intermediate portion of the flat plate-shaped thin plate ring is bent in the plate thickness direction by the action of the pair of pressing means. It deforms and spring force is generated. Since the thin plate ring has a spring action in this deformed state, even if a large heat load is applied to the seal surface and a large distortion occurs in the seal surface, the seal surface is always in a close contact state and high sealing performance can be maintained. it can. Therefore, it is most suitable as a sealing device to be used especially under conditions of high temperature and large heat load.

Further, the sealing device for the pipe connecting portion is composed only of the thin plate ring having high heat resistance and elasticity and the pressing means, and since no gasket material which is easily affected by heat is used, it is large. Even if a heat load is applied, there is no problem of volume reduction or deterioration unlike the conventional case, and the sealing property does not deteriorate, so it is extremely reliable,
A highly durable seal ring can be provided.

Further, since it is easy to change to a structure in which a plurality of the thin plate rings are stacked, if the annular groove is deeply formed and the thin plate rings are stacked and used, the sealing property of this seal ring is improved. It can be further improved.

Regarding the sealing device for this pipe connection,
Since the compression amount, that is, the bending amount can be appropriately increased by constructing a plurality of sets of the assembly composed of the thin plate ring and the pressing means in an overlapping manner, it is possible to increase the thermal deformation of the pipe connection portion. By appropriately selecting the number of sets of the assembly, it is possible to provide the sealing device which secures the optimum amount of bending, that is, the amount of compression, and has a large sealing force at the pipe connecting portion.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of an exhaust manifold incorporating a sealing device for a pipe connection portion according to the present invention.

FIG. 2 is a side view seen from the line AA side in FIG.

FIG. 3 is a sectional view showing an embodiment of a sealing device for a pipe connecting portion according to the present invention.

4 is an enlarged cross-sectional view of a region B of FIG. 1, and is an explanatory view showing a state in which the sealing device for the pipe connecting portion of FIG. 3 is fitted in the annular groove and the pipe body is tightened.

FIG. 5 is a cross-sectional view showing another embodiment of the sealing device for a pipe connecting portion according to the present invention.

FIG. 6 is a cross-sectional view showing still another embodiment of the sealing device for a pipe connecting portion according to the present invention.

FIG. 7 is a cross-sectional view showing an example of a conventional sealing device for a pipe connecting portion.

FIG. 8 is a perspective view showing an example of a flange in the sealing device for the pipe connecting portion of FIG. 7.

9 is a cross-sectional view showing an example of a seal ring in the sealing device of the pipe connecting portion of FIG.

[Explanation of symbols]

6 Annular groove 7 Tubular body 8 Tubular body 10 Seal ring 11, 14, Ceramic thin plate ring (thin plate ring) 12 Metal thin plate ring (pressing means: holding thin plate ring) 13 Ring-shaped intermediate plate (pressing means: intermediate plate) ) 15 first metal thin plate ring (pressing means) 16 second metal thin plate ring (pressing means) 17 overlapping portion (pressing means) 18 first ceramic spring ring (first thin plate ring) 19 second ceramic spring ring (Second thin plate ring) 20 Ring-shaped intermediate plate (pressing means) 21 First metal thin plate ring (pressing means: first holding thin plate ring) 22 Second metal thin plate ring (pressing means: second holding) Thin plate ring)

Claims (7)

[Claims] 1. A sealing device for a pipe connecting portion, comprising: a pair of pipes having surfaces facing each other and tightened with each other; and a seal ring arranged between the pipes facing each other. A heat-resistant and elastic thin plate ring, and an edge portion of the thin plate ring is held, and the circumferential intermediate portion of the thin plate ring is deformed in the plate thickness direction in a tightened state of the pair of pipe bodies. A sealing device for a pipe connecting portion, comprising: a pressing means for generating a spring force on a thin plate ring. 2. The pressing means is made of a metal holding thin plate ring, and is arranged concentrically between the holding thin plate ring and the thin plate ring, and the holding thin plate ring and the thin plate ring. And a ring-shaped intermediate plate that forms a gap between which the thin plate ring can be deformed, and the thin plate ring for holding holds the inner and outer parts of the thin plate ring by bending the holding parts. The sealing device for a pipe connecting portion according to claim 1, further comprising: 3. The pressing means includes a first holding thin plate ring that holds the inner portion of the thin plate ring inside and a second holding thin plate that holds the outer side portion of the thin plate ring inside the outer portion. It consists of a ring, The outer side part of the said 1st holding | maintenance thin plate ring and the inner side part of the said 2nd holding | maintenance thin plate ring were overlap | superposed in the intermediate part, and the overlapping part which differs in thickness was formed, It is characterized by the above-mentioned. 1. The sealing device for a pipe connection part according to 1. 4. The thin plate ring comprises a first thin plate ring and a second thin plate ring that are concentrically arranged opposite to each other, and the pressing means is concentric between the first thin plate ring and the second thin plate ring. Of the ring-shaped intermediate plate arranged above, the first holding plate ring for holding the inside parts of the first plate ring and the second plate ring together, and the first plate ring and the second plate ring. 2. The sealing device for a pipe connecting portion according to claim 1, which comprises a second holding thin plate ring for holding the outer portions together. 5. The sealing device for a pipe connecting portion according to claim 2, wherein the intermediate plate is joined to the thin plate ring. 6. The sealing device for a pipe connecting portion according to claim 1, wherein the thin plate ring is made of ceramics or metal. 7. The sealing device for a pipe connecting portion according to claim 1, wherein a plurality of sets of assemblies each composed of the thin plate ring and the pressing means are superposed on each other.