JPH10132148A - Double pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To alleviate stress to an inner pipe and an outer pipe, to be generated caused by heat expansion, in a double pipe in which the inner pipe and the outer pipe are coaxially arranged. SOLUTION: A double pipe is provided with a vibrationproof member 11 formed of a mesh spring material so arranged as to be brought in surface- contact with the outer peripheral surface of an inner pipe 3, a pressure receiving member 12 for integrally coating a part other than a part near an inner pipe contact surface 11a of the vibrationproof member 11 and to be brought in contact with the inner peripheral surface of the outer pipe 5, and a guide member 13 for allowing the displacement of the pressure receiving member 12 in the pipe diameter direction and for restricting the displacement in the pipe circumferential direction and the pipe axial direction. When the relative displacement in the radial direction is generated between the inner pipe 3 and the outer pipe 5, the vibrationproof member 11 is made flex to alleviate stress to the inner pipe 3 and the outer pipe 5, and the relative displacement in the radial direction between the inner pipe 3 and the outer pipe 5 is restrained by restoring force of the vibrationproof member 11 against flexure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double pipe proposed as a means for supplying a high-temperature fluid.

[0002]

2. Description of the Related Art FIG. 6 to FIG. 8 show that secondary helium gas heated by cooling a core of a high-temperature gas reactor through an intermediate heat exchanger by primary helium heated is sent to a heat utilization system. 1 shows an example of a double pipe proposed as a means for supplying secondary helium gas whose temperature has been reduced by a heat utilization system to an intermediate heat exchanger.

[0003] This double pipe comprises an inner pipe 3 in which a thin-walled tubular liner 1 is coaxially housed through a heat insulating material 2, and a gas flow between the inner pipe 3 and a gas to supply gas to an intermediate heat exchanger. An outer tube 5 circumferentially surrounds the inner tube 3 so that a passage 4 is formed.

[0004] Inside the liner 1, a secondary helium gas before heat exchange to be sent from the intermediate heat exchanger to the heat utilization system flows, and between the inner tube 3 and the outer tube 5. The secondary helium gas after heat exchange to be sent from the heat utilization system to the intermediate heat exchanger flows through the gas flow path 4.

[0005] At a predetermined portion of the intermediate portion of the outer tube 5,
A clamp 6 is externally fitted, and a snapper 7 interconnecting the clamp 6 and a fixed structure (not shown) located near the outer tube 5 attenuates radial deflection of the outer tube 5. It has become so.

[0006] Further, at a predetermined position of the intermediate portion of the inner tube 3,
A spacer 8 is fixed so that a gap is formed with respect to the inner peripheral surface of the outer tube 5.
Is suppressed in the radial direction.

[0007]

However, in the double pipe constituted by the inner pipe 3 and the outer pipe 5 as described above, the gas flows through the gas flow path 4 between the inner pipe 3 and the outer pipe 5. Since the temperature of the secondary helium gas flowing inside the inner tube 3 is higher than the temperature of the secondary helium gas, the inner tube 3 has a higher temperature than the outer tube 5.
, A greater thermal expansion occurs.

[0008] Further, as shown in FIG.
When the ends of the two double pipes formed by the above are connected via a double pipe elbow formed by the internal elbow member 3a and the external elbow member 5a, If the distance between the connecting portion 9 and the heavy pipe elbow is short,
When thermal expansion occurs in the inner tube 3, the spacer 8 interferes with the outer tube 5 and the displacement of the inner tube 3 is suppressed, so that excessive stress acts on the inner tube 3 and the outer tube 5.

For this reason, in the double pipe applied to the means for transferring the secondary helium gas between the intermediate heat exchanger and the heat utilization system, the double pipe is connected to the spacer 8 as described above. It is necessary to extend the length of the double pipe so that the connection portion 9 with the double pipe elbow is sufficiently spaced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a double pipe capable of reducing stress on an inner pipe and an outer pipe due to thermal deformation.

[0011]

In order to achieve the above object, in the double pipe according to the first aspect of the present invention, in a double pipe in which an outer pipe is loosely fitted coaxially with an inner pipe, an outer circumference of the inner pipe is provided. A vibration isolating member made of a mesh spring material arranged so as to be in surface contact with the surface, and a portion excluding a portion near the inner tube contact surface of the vibration isolating member, and integrally covering the inner peripheral surface of the outer tube. A pressure receiving member is provided, and a guide member that allows displacement of the pressure receiving member in the pipe radial direction and restricts displacement in the pipe circumferential direction and the pipe axis direction.

In the double pipe according to the second aspect of the present invention,
A double pipe in which an outer pipe is loosely fitted coaxially with an inner pipe, and has a fluid circulation hole formed in an annular shape capable of making surface contact with the outer peripheral surface of the inner pipe and the inner peripheral surface of the outer pipe, and penetrating in the axial direction of the member. A vibration isolating member made of a mesh spring material, and the vibration isolating member is disposed such that an inner edge thereof is inscribed in the inner tube and an outer edge thereof is inscribed in the outer tube.

In the double pipe according to the first aspect of the present invention, when a relative displacement occurs in the radial direction between the inner pipe and the outer pipe, the outer peripheral surface of the inner pipe and the inner circumference of the outer pipe. The vibration isolator of the vibration isolator, which is disposed at the position where the surface is approaching, bends to relieve stress on the inner and outer pipes, and the restoring force of the vibration isolator against the deflection causes the inner pipe and the outer Suppresses relative displacement in the radial direction with the tube.

When a difference in extension in the pipe axis direction or a twist in the pipe circumferential direction occurs between the inner pipe and the outer pipe, the pressure-receiving member slides on the inner circumferential surface of the outer pipe, and the inner pipe has an inner pipe. Relative displacement in the axial direction and in the circumferential direction of the outer tube and the outer tube.

In the double pipe according to the second aspect of the present invention, when a relative displacement in the radial direction occurs between the inner pipe and the outer pipe, the outer peripheral surface of the inner pipe and the outer pipe of the inner pipe are connected to the vibration isolating member. The portion located at the location where the inner peripheral surface of the pipe is approaching is deflected to relieve stress on the inner pipe and the outer pipe, and the restoring force of the vibration isolating member against the deflection causes the diameter of the inner pipe and the outer pipe to be reduced. Suppress relative displacement in the direction.

If a difference in extension between the inner tube and the outer tube in the axial direction of the tube or a twist in the circumferential direction of the tube occurs, the inner edge and the outer edge of the vibration damping member are fixed to the outer peripheral surface of the inner tube. It slides on the inner peripheral surface of the pipe, and allows relative displacement of the inner pipe and the outer pipe in the pipe axis direction and the pipe circumferential direction.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment of a double tube according to the present invention. In the drawings, the same reference numerals as in FIGS. 6 to 8 denote the same parts. Represents.

The double pipe shown in FIG. 1 and FIG.
It is composed of an outer tube 5 and a plurality of vibration isolators 10.

As shown in FIG. 3, the vibration isolator 10
Inner tube contact surface 1 formed so as to be in surface contact with the outer peripheral surface of
1a, a vibration isolating member 11 made of a rectangular mesh spring material, and a portion of the vibration isolating member 11 except for a portion near an inner tube contact surface 11a, which is integrally covered and has a closed end surface 12a.
A square cap type pressure receiving member 12 having an outer shape capable of contacting the inner peripheral surface of the outer tube 5, and slidably surrounds four sides of the pressure receiving member 12, and has one end on the outer peripheral surface of the inner tube 3. The guide member 13 is formed in a square hollow shape so as to be fixed.

The mesh spring material used for the above-described vibration isolating member 11 is formed by knitting a thin wire (element wire) such as stainless steel having a high tensile strength into a knitted shape and flattening and corrugating the wire. It is an elastic body that is compression molded in a mold so as to have a density.

In the double pipe shown in FIGS. 1 to 3, a plurality of guide members 13 are arranged and fixed on the outer peripheral surface of the inner pipe 3 at predetermined equal intervals in the circumferential direction. Then, the vibration isolating member 11 covered with the pressure receiving member 12 is inserted so that the inner pipe contact surface 11 a is in surface contact with the outer peripheral surface of the inner pipe 3. Are inserted so that they can slide in the radial direction.

Further, as described above, the plurality of vibration isolators 1
By inserting the inner tube 3 fitted with “0” into the outer tube 5, the closed end surface 12 a of the pressure receiving member 12 of each vibration isolator 10 is brought into contact with the inner peripheral surface of the outer tube 5.

The operation of the double pipe shown in FIGS. 1 to 3 will be described below.

Since the vibration isolating member 11 is formed of a mesh spring material formed by processing a thin wire such as stainless steel as described above, the vibration isolating member 11 bends when an external force is applied to the pressure receiving member 12, A restoring force (reaction force) corresponding to the amount of bending is generated between the inner tube 3 and the outer tube 5.

That is, in the double pipes shown in FIGS. 1 to 3, if a relative radial displacement between the inner pipe 3 and the outer pipe 5 is caused due to a difference in thermal expansion or the like, An anti-vibration member 11 is provided via a pressure receiving member 12 of an anti-vibration device 10 disposed at a location where the outer peripheral surface of the inner tube 3 and the inner peripheral surface of the outer tube 5 are approaching.
, An external force is applied, and the vibration damping member 11 bends to reduce stress on the inner pipe 3 and the outer pipe 5.

Further, a reaction force corresponding to the amount of deflection of the vibration isolating member 11 is generated between the inner tube contact surface 11a of the vibration isolating member 11 and the pressure receiving member 12, and the reaction force causes the inner tube 3 and the outer tube 5 is suppressed in the radial direction.

Further, if a difference in elongation in the tube axis direction or a twist in the tube circumferential direction occurs between the inner tube 3 and the outer tube 5 due to a difference in thermal expansion or the like, the pressure receiving member 12 is moved to the outer tube. 5, the inner tube 3 and the outer tube 5 are allowed to move relative to each other in the tube axis direction and the tube circumferential direction.

On the other hand, when vibration occurs in the inner pipe 3 and the outer pipe 5 due to an earthquake or the like, the vibration isolator 11 of the vibration isolator 10
The vibration of the inner pipe 3 and the outer pipe 5 is attenuated.

Therefore, assuming that the double pipe shown in FIGS. 1 to 3 thermally expands as shown in FIG. 8, when the inner pipe is thermally deformed, the inner pipe 3 and the outer pipe are 5 is relieved.

That is, if the double pipe shown in FIGS. 1 to 3 is applied to the means for transferring the secondary helium gas between the intermediate heat exchanger and the heat utilization system as described above, the protection can be prevented. Shaker 1
It is possible to reduce the interval between the connection pipe 9 and the connecting portion 9 (see FIG. 8), and the length of the double pipe can be reduced.

FIGS. 4 and 5 show a second embodiment of the double tube according to the present invention, in which the same reference numerals as in FIGS. 1 and 2 denote the same parts. Represents.

The double pipe shown in FIG. 4 and FIG.
It is constituted by the outer tube 5 and the vibration isolating member 14.

The vibration isolating member 14 is an annular body having an inner edge portion 14a that can make surface contact with the outer peripheral surface of the inner tube 3 and an outer edge portion 14b that can make surface contact with the inner peripheral surface of the outer tube 5; It is formed of a mesh spring material provided with a plurality of fluid communication holes 15 penetrating through.

The mesh spring material used for the vibration isolating member 14 is formed by knitting a thin wire (element wire) such as stainless steel having a high tensile strength into a knitted shape, corrugating the wire flat, and then forming the fluid flow hole 15. Is an elastic body that is compression-molded in a mold so as to have a predetermined density.

In the double pipe shown in FIGS. 4 and 5, when the vibration damping member 14 is fitted to the inner pipe 3, the inner edge 14 a is pressed against the outer peripheral surface of the inner pipe 3 by the elastic force of the mesh spring material. Then, the vibration isolating member 14 is fixed to the inner pipe 3.

Further, as described above, the annular vibration isolator 1
By inserting the inner tube 3 fitted with the outer tube 4 into the outer tube 5, the outer edge portion 14 b of each vibration isolating member 14 is brought into contact with the inner peripheral surface of the outer tube 5.

Hereinafter, the operation of the double pipe shown in FIGS. 4 and 5 will be described.

As described above, since the vibration isolating member 14 is formed of a mesh spring material formed by processing a thin wire such as stainless steel, it is bent when an external force is applied. A restoring force (reaction force) is generated between the inner edge 14a and the outer edge 14b of the vibration isolating member 14.

That is, in the double pipe shown in FIGS. 4 and 5, if a relative radial displacement between the inner pipe 3 and the outer pipe 5 is caused due to a difference in thermal expansion or the like, it is prevented. In the vibration member 14, an external force is applied to a portion located at a position where the outer peripheral surface of the inner tube 3 and the inner peripheral surface of the outer tube 5 approach each other, and the vibration-proof member 14 is bent to cause the inner tube 3 and the outer tube 5 to move. Relieve stress.

A reaction force corresponding to the amount of deflection of the vibration isolating member 14 is generated between the inner edge portion 14a and the outer edge portion 14b of the vibration isolating member 14, and the reaction force causes the inner tube 3 and the outer tube 5 to move. Relative radial displacement is suppressed.

Further, if a difference in extension between the inner pipe 3 and the outer pipe 5 in the pipe axis direction or a twist in the pipe circumferential direction occurs due to a difference in thermal expansion or the like, the inner edge of the vibration isolator 14 Part 14a, outer edge 1
4b slides on the outer peripheral surface of the inner tube 3 and the inner peripheral surface of the outer tube 5, and relative displacement of the inner tube 3 and the outer tube 5 in the tube axis direction and the tube circumferential direction is allowed. become.

On the other hand, when vibration occurs in the inner pipe 3 and the outer pipe 5 due to an earthquake or the like, the vibration isolator 14 attenuates the vibration of the inner pipe 3 and the outer pipe 5.

Therefore, assuming that the double pipe shown in FIGS. 4 and 5 thermally expands as shown in FIG. 8, when the inner pipe is thermally deformed, the inner pipe 3 and the outer pipe are 5 is relieved.

That is, if the double pipe shown in FIGS. 4 and 5 is applied to the means for transmitting and receiving the secondary helium gas between the intermediate heat exchanger and the heat utilization system as described above, the protection can be prevented. The distance between the vibration member 14 and the connection portion 9 (see FIG. 8) can be reduced, and the length of the double pipe can be reduced.

It should be noted that the double pipe of the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[0047]

As described above, according to the double pipe of the present invention, the following various excellent effects can be obtained.

(1) In any of the double pipes according to the first and second aspects, relative radial displacement may occur between the inner pipe and the outer pipe due to a difference in thermal expansion or the like. Then
The vibration isolator flexes to reduce the stress on the inner and outer pipes, while suppressing the relative radial displacement between the inner and outer pipes. The resulting stress on the inner tube and the outer tube can be reduced.

(2) In any of the double pipes according to the first and second aspects, since the stress on the inner pipe and the outer pipe due to thermal deformation is reduced, the double pipe can be used as another member. In the case of connection, it is possible to shorten the length of the double pipe, and thus it is possible to improve the economical efficiency of the plant.

(3) In any of the double pipes according to the first and second aspects, since the vibration isolating member attenuates the displacement of the inner pipe and the outer pipe, the vibration of the inner pipe and the outer pipe is reduced. be able to.

(4) In the double pipe according to the first aspect of the present invention, if a difference in extension between the inner pipe and the outer pipe in the axial direction of the pipe or a twist in the circumferential direction of the pipe occurs, the pressure receiving pressure is increased. Since the member slides on the inner peripheral surface of the outer pipe, relative displacement of the inner pipe and the outer pipe in the pipe axis direction and the pipe circumferential direction can be allowed.

(5) In the double pipe according to the second aspect of the present invention, if a difference in extension between the inner pipe and the outer pipe in the axial direction of the pipe or a twist in the circumferential direction of the pipe occurs, it is prevented. Since the inner edge and the outer edge of the vibration member slide with respect to the outer peripheral surface of the inner pipe and the inner peripheral surface of the outer pipe, the relative displacement of the inner pipe and the outer pipe in the pipe axis direction and the pipe circumferential direction is reduced. Can be tolerated.

[Brief description of the drawings]

FIG. 1 is a sectional view in a direction parallel to a tube axis showing a first example of an embodiment of a double tube of the present invention.

FIG. 2 is a sectional view taken along a direction perpendicular to the tube axis related to FIG. 1;

FIG. 3 is a perspective view of a vibration isolator related to FIG. 1;

FIG. 4 is a sectional view taken in a direction parallel to the tube axis, showing a second example of the embodiment of the double tube of the present invention.

FIG. 5 is a sectional view taken along a direction perpendicular to the tube axis related to FIG. 4;

FIG. 6 is a sectional view in the direction parallel to the tube axis showing an example of a conventional double tube.

7 is a sectional view taken along the direction perpendicular to the tube axis related to FIG. 6;

FIG. 8 is a conceptual diagram showing an example of a bent tube to which the double tube of FIG. 6 is applied.

[Explanation of symbols]

 Reference Signs List 3 inner pipe 5 outer pipe 11 anti-vibration member 12 pressure receiving member 13 guide member 14 anti-vibration member 15 fluid flow hole

Claims (2)

[Claims] In a double pipe in which an outer pipe is coaxially loosely fitted to an inner pipe, a vibration isolator made of a mesh spring material arranged so as to be in surface contact with the outer peripheral surface of the inner pipe; A pressure-receiving member that integrally covers a portion other than a portion near the inner-tube contact surface and abuts against the inner peripheral surface of the outer tube; a displacement member that allows displacement of the pressure-receiving member in the tube radial direction; A double pipe comprising a guide member for restraining displacement in an axial direction. 2. A double tube in which an outer tube is coaxially loosely fitted with an inner tube, and is formed in an annular shape capable of making surface contact with the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube and penetrates in the axial direction of the member. A vibration isolating member made of a mesh spring material having a fluid circulation hole, wherein the vibration isolating member is arranged such that an inner edge portion is inscribed in the inner tube and an outer edge portion is inscribed in the outer tube. tube.