JP2019184104A - Overheating steam generation device - Google Patents

Abstract

To reduce the temperature distribution of a conductor pipe, to reduce the usage of a heat insulation material.SOLUTION: An overheating steam generator 100 that heats steam flowing in a conductor pipe 2 by induction heating or energization heating of the conductor tube 2 wound in a spiral manner, to generate overheating steam, comprises a heat transfer member 9 provided along a winding axis C of the conductor tube 2 in at least one of the radially inner side or radially outer side of the conductor tube 2, and a heat insulating material 10 provided so as to cover the conductor tube 2 and the heat transfer member 9.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a superheated steam generating device that generates superheated steam by heating steam flowing in a conductor pipe by induction-heating or energizing heating of a spirally wound conductor pipe.

  In this type of superheated steam generator, as shown in Patent Document 1, a plurality of conductor tubes wound in a spiral form forming a secondary coil are electrically connected by welding or the like with an electrical connection member extending in the axial direction of the spiral. It is known to connect and configure a short circuit to reduce electrical reactance and improve heating efficiency.

  This superheated steam generator, for example, introduces steam at 120 ° C. into a spiral conductor tube and heats it to generate superheated steam at 700 to 1200 ° C., for example. Since the apparatus handles high-temperature water vapor in this way, a heat insulating material is provided around the spiral conductor tube.

JP 2010-71624 A

  However, conventionally, the amount of heat insulating material used is determined in accordance with the temperature of the outlet portion that is a high temperature (eg, 700 to 1200 ° C.) of the spiral conductor tube, and the relatively low temperature (eg, 120 ° C.) of the spiral conductor tube. At the entrance portion, there will be an excessive amount of heat insulating material. In addition, although it is possible to vary the thickness of a heat insulating material etc. according to the temperature distribution of a helical conductor tube, the design and assembly will become complicated.

  Accordingly, the present invention has been made to solve the above-described problems, and its main purpose is to reduce the amount of heat insulating material used by reducing the temperature distribution (temperature gradient) of the device caused by the heating temperature of the conductor tube. It is a problem.

  That is, the superheated steam generator according to the present invention is a superheated steam generator that generates superheated steam by heating the steam flowing in the conductor tube by induction heating or current heating of the spirally wound conductor tube. A heat transfer member provided along a winding axis direction of the conductor tube on at least one of the radially inner side and the radially outer side of the conductor tube, and the conductor tube and the heat transfer member. And a heat insulating material.

  According to this superheated steam generator, since the heat transfer member is provided along the winding axis direction of the conductor tube on at least one of the radially inner side and the radially outer side of the conductor tube, the temperature distribution in the peripheral member of the conductor tube (Temperature gradient) can be reduced. As a result, the temperature of the peripheral portion of the conductor tube in the vicinity of the superheated steam outlet can be lowered, so that the amount of heat insulating material used can be reduced. In addition, by reducing the amount of heat insulating material used, the apparatus can be miniaturized and the material cost can be reduced.

  In order to reduce the temperature distribution in the circumferential direction, it is desirable that the heat transfer member is provided over the circumferential direction.

It is desirable that the heat transfer member is provided so as to surround the conductor tube on a radially outer side of the conductor tube.
With this configuration, the volume of the heat transfer member can be increased without difficulty, and the heat transfer effect can be enhanced. Further, since the heat transfer member surrounds the conductor tube that is a heat source, heat leaking from the conductor tube to the outside can be confined inside.

Specific embodiments of the fluid heating device include an inner iron core provided inside the conductor tube, a magnetic path forming unit that is provided outside the conductor tube and forms a closed magnetic circuit with the iron core, An induction coil that is provided between the iron core and the magnetic path forming portion and generates a magnetic flux inside the iron core; and a preheating tube that is provided between the iron core and the magnetic path forming portion and through which the water vapor flows, The preheating tube is connected to the conductor tube, and the water vapor is configured to flow through the conductor tube after flowing through the preheating tube.
If it is this structure, water vapor | steam can be preheated using the heat | fever leaked outside from the conductor pipe | tube. That is, water vapor can be efficiently heated by reducing loss due to heat radiation from the conductor tube.

The preheating tube preferably includes an outer preheating tube provided between the conductor tube and the magnetic path forming portion, and an inner preheating tube provided between the conductor tube and the iron core.
If it is this structure, it can be set as the structure which sandwiches the radial direction both sides of a conductor pipe with an outer side preheating pipe and an inner side preheating pipe, and in order to demonstrate the function which intercepts the heat leaked from the conductor pipe to both sides in the radial direction, The amount of material used can be reduced.

The heat transfer member may include an outer heat transfer member provided between the conductor tube and the outer preheat tube, and an inner heat transfer member provided between the conductor tube and the inner preheat tube. desirable.
If it is this structure, while making temperature distribution small in the part close | similar to a conductor pipe | tube, the water vapor | steam which flows through an outer side preheating pipe and an inner side preheating pipe | tube can be heated with the temperature equalized by the heat-transfer member.

As described above, the conductor tube of the superheated steam generation device introduces, for example, 120 ° C. water vapor and derives, for example, 700 to 1200 ° C. superheated water vapor. It is necessary to use a material having a temperature (for example, Inconel). However, when Inconel is used as the material of the conductor tube, the material cost becomes high.
Therefore, it is desirable that the conductor tube is made of different metals for the upstream portion and the downstream portion.
If it is this structure, the material selection according to the temperature of the upstream part of a conductor pipe and the temperature of a downstream part can be performed, a rational design of a conductor pipe is attained, and the material cost of a conductor pipe is reduced. be able to.

  Specifically, it is desirable that the heat resistance temperature of the metal forming the upstream portion is lower than the heat resistance temperature of the metal forming the downstream portion.

  In order to simplify the configuration of the conductor tube and reduce its manufacturing cost, it is desirable that the upstream portion and the downstream portion are connected by welding.

  Specifically, the upstream portion is made of stainless steel (for example, SUS304, SUS316, etc.) that is a general-purpose alloy steel, and the downstream portion is made of Inconel, which is a super heat resistant steel. desirable.

  According to the present invention configured as described above, the heat transfer member is provided along the winding axis direction of the conductor tube on at least one of the radially inner side or the radially outer side of the conductor tube. The temperature distribution of the resulting device can be made uniform to reduce the amount of heat insulating material used.

It is sectional drawing which shows typically the structure of the superheated steam generation apparatus which concerns on this embodiment. It is a figure which shows typically arrangement | positioning in the radial direction of the superheated steam generator of the embodiment. It is sectional drawing which shows typically the structure of the conductor pipe | tube of the embodiment. It is a front view which shows typically the structure of the conductor pipe | tube of the embodiment. It is a figure which shows the circuit of the short circuit current in the conductor pipe | tube of the embodiment. It is the top view and front view which show typically the structure of the inner side iron core of the embodiment. It is the top view and front view which show typically the structure of the outer side iron core of the embodiment. It is a top view which shows typically the structure of the yoke core of the same embodiment. It is a figure which shows the modification of a conductor pipe typically. It is a figure which shows typically arrangement | positioning in the radial direction of the superheated steam generator of deformation | transformation embodiment.

<1. Device configuration>
The superheated steam generator 100 according to the present embodiment heats, for example, 120 ° C. steam generated outside to generate superheated steam of, for example, 700 to 1200 ° C. In addition, the superheated steam generator 100 may have a saturated steam generator that heats water and generates, for example, 120 ° C. steam.

  Specifically, the superheated steam generation apparatus 100 generates superheated steam by heating the steam flowing in the conductor tube 2 by induction heating the conductor tube 2, and as shown in FIG. 1 and FIG. A conductor tube 2 wound in a shape, an inner iron core 3 provided inside the conductor tube 2, a magnetic path forming portion 4 provided outside the conductor tube 2 and forming a closed magnetic circuit with the inner iron core 3, An induction coil 5 provided between the inner iron core 3 and the magnetic path forming portion 4 and generating magnetic flux inside the inner iron core 3, and a preheat tube provided between the inner iron core 3 and the magnetic path forming portion 4 through which water vapor flows. 6 and so on.

  The conductor tube 2 is wound spirally (coiled) along a predetermined center axis. Specifically, as shown in FIGS. 3 and 4, the conductor tube 2 includes an inner tube element 21 spirally wound, and an outer tube element provided outside the inner tube element 21 and spirally wound. 22 and connecting pipe elements 23a and 23b for fluidly connecting the inner pipe element 21 and the outer pipe element 22 and short-circuiting them. In addition, as a material of the conductor tube 2, it is stainless steel (SUS304, SUS316 etc.) which is general purpose alloy steel, Inconel which is super heat resistant steel, etc.

  The winding directions of the inner tube element 21 and the outer tube element 22 are opposite to each other (see FIG. 3). And the axial direction one end part of the inner side pipe element 21 and the axial direction one end part of the outer side pipe element 22 are connected by the connection pipe element 23a. The other axial end of the inner tube element 21 and the other axial end of the outer tube element 22 are connected by a connecting tube element 23b.

  The connecting pipe element 23a is provided with a steam introduction port 2p1, and the connecting pipe element 23b is provided with a superheated steam outlet port 2p2. With this configuration, the water vapor flowing in from the introduction port 2p1 of the connection pipe element 23a branches and flows into the inner pipe element 21 and the outer pipe element 22 through the connection pipe element 23a, and flows through the inner pipe element 21 and the outer pipe element 22. The steam (superheated steam) joins at the connecting pipe element 23b and flows out from the outlet port 2p2.

  Further, the conductor tube 2 connected in this way is configured such that the inner tube element 21 and the outer tube element 22 are electrically connected in parallel by the connecting tube element 23. Then, a short-circuit current flows through the inner tube element 21 and the outer tube element 22 by the magnetic flux generated by the induction coil 5 as shown in FIG. That is, a short-circuit current flows through the inner tube element 21 from the one axial end portion 21a toward the other axial end portion 21b, and the outer tube element 22 proceeds from the other axial end portion 22b toward the one axial end portion 22a. Short circuit current flows. With this configuration, it is not necessary to provide an electrical connection member separately from the conductor tube 2, and a short circuit can be formed by the configuration of the conductor tube 2 itself.

  As shown in FIGS. 1 and 2, the inner iron core 3 is disposed coaxially with the inner tube element 21 of the conductor tube 2 inside the conductor tube 2. As shown in FIG. 6 (A), the inner iron core 3 of the present embodiment is a so-called involute iron core, and a plurality of silicon steel plates having a curved portion whose cross section in the width direction is curved in an involute curve shape radially in the circumferential direction. They are stacked and formed into a cylindrical shape. As shown in FIG. 6B, the inner iron core 3 may be formed by stacking flat silicon steel plates into a cylindrical shape.

  As shown in FIG. 1, the magnetic path forming unit 4 forms a closed magnetic path together with the inner iron core 3, and a plurality of outer iron cores 41 arranged at equal intervals in the circumferential direction on the outside of the conductor tube 2, It has the upper and lower yoke cores 42 that connect the upper ends and the lower ends of the inner iron core 3 and the plurality of outer iron cores 41. The outer iron core 41 may not be equally spaced in the circumferential direction.

  As shown in FIG. 2, the outer iron core 41 is disposed coaxially with the conductor tube 2 on the outer side of the conductor tube 2. In the present embodiment, the three outer iron cores 41 are arranged at equal intervals in the circumferential direction on the outer side of the conductor tube 2. Each outer iron core 41 of the present embodiment is composed of two outer iron core elements 411 and 412 arranged in parallel in relation to a yoke core 42 described later. Further, as shown in FIG. 7, each of the outer core elements 411 and 412 is formed by stacking flat silicon steel plates into a semi-columnar shape or a semi-cylindrical shape. Thereby, the superheated steam generator 100 is downsized in the radial direction. The outer iron core 41 may be composed of one outer iron core element.

  Each of the upper and lower yoke cores 42 is composed of three yoke core elements 421, 422, and 423 as shown in FIG. 8, and each of the yoke core elements 421, 422, and 423 is constituted by deforming the annular wound core. Has been. Specifically, each of the yoke core elements 421, 422, and 423 is configured by deforming an annular wound core into a dogleg shape that is bent at the center. A Y-shaped yoke core 42 is configured by combining these three yoke core elements 421, 422, and 423 so that their bent portions are located on the center side. The outer core elements 411 and 412 are connected to both ends of the yoke elements 421, 422 and 423, respectively. Further, the inner core 3 is connected to the central portion of the yoke core 42. That is, the three outer iron cores 41 are located at the vertices of the equilateral triangle, and the inner iron core 3 is located at the center of gravity of the equilateral triangle. Each of these parts is fastened from the axial direction by a fastening mechanism 8 such as a fastening bolt via a clamping member 7 that sandwiches the inner iron core 3, the outer iron core 41, and the yoke core 42.

  As shown in FIGS. 1 and 2, the induction coil 5 includes an inner induction coil 51 wound around the inner iron core 3 and an outer induction coil 52 wound inside the outer iron core. . These induction coils 51 and 52 are arranged coaxially with the inner iron core 3. A single-phase power supply (not shown) of 50 Hz or 60 Hz is connected to the induction coils 51 and 52. The inner induction coil 51 and the outer induction coil 52 are connected to each other in series or in parallel.

  The preheating tube 6 is wound in a spiral shape (coil shape) coaxially with the winding axis C of the conductor tube 2. Specifically, as shown in FIGS. 1 and 2, the preheating tube 6 is provided inside the conductor tube 2, and is provided inside the conductor tube 2 and the inner preheating tube 61 wound spirally, and is provided in a spiral shape. And an outer preheating tube 62 wound around.

  The inner preheating tube 61 is provided between the conductor tube 2 and the inner iron core 3, more specifically, between the conductor tube 2 and the inner induction coil 51. The outer preheating tube 62 is provided between the conductor tube 2 and the outer iron core 41, more specifically, between the conductor tube 2 and the outer induction coil 52.

  One end of the inner preheating tube 61 is provided with an introduction port 61p through which water vapor generated outside is introduced. The other end of the inner preheating pipe 61 is connected to the other end of the outer preheating pipe 62. Furthermore, one end of the outer preheating pipe 62 is connected to the introduction port 2p1 of the conductor pipe 2. That is, the water vapor introduced from the introduction port 61 p of the inner preheating pipe 61 flows into the conductor pipe 2 after flowing through the inner preheating pipe 61 and the outer preheating pipe 62.

  Here, the winding direction of the inner preheating tube 61 and the winding direction of the outer preheating tube 62 are configured to be opposite to each other. As a result, the phase of the induced voltage induced in the inner preheating tube 61 and the phase of the induced voltage induced in the outer preheating tube 62 are reversed, and the short-circuit currents generated in the inner preheating tube 61 and the outer preheating tube 62 cancel each other. be able to.

  In the superheated steam generator 100 configured as described above, by applying an AC voltage to the induction coil 5 from a single-phase power source, a current flows through the inner induction coil 51 and the outer induction coil 52, and the inner iron core 3 and the magnetic path forming unit. Magnetic flux flows through 4. The magnetic flux causes a short-circuit current to flow through the inner tube element 21, the outer tube element 22, and the connecting tube elements 23a and 23b of the conductor tube 2, and the conductor tube 2 generates Joule heat. Thereby, the water vapor | steam which flows through the conductor pipe | tube 2 is heated, and superheated water vapor | steam is produced | generated.

  However, as shown in FIGS. 1 and 2, the superheated steam generator 100 of the present embodiment includes a heat transfer member 9 that reduces a temperature gradient (temperature distribution) in the winding axis direction caused by the heating temperature of the conductor tube 2. Is provided.

  The heat transfer member 9 of the present embodiment includes an inner heat transfer member 91 along the winding axis C of the conductor tube 2 on the radially inner side of the conductor tube 2 and a winding of the conductor tube 2 on the radially outer side of the conductor tube 2. It is the outer heat transfer member 92 along the axis C.

  The inner heat transfer member 91 is provided between the conductor tube 2 and the inner preheating tube 61. The inner heat transfer member 91 is provided substantially over the entire circumferential direction. Specifically, the inner heat transfer member 91 is provided so as to surround the inner preheating tube 61, and has a partial cylindrical shape such as a C shape in which a slit is partially formed along the axial direction. The inner heat transfer member 91 is a curved plate made of a material having excellent heat conductivity such as aluminum or copper.

  The outer heat transfer member 92 is provided between the conductor tube 2 and the outer preheating tube 62. The outer heat transfer member 92 is provided substantially over the entire circumferential direction. Specifically, the outer heat transfer member 92 is provided so as to surround the conductor tube 2, and has a partial cylindrical shape such as a C shape in which a slit is partially formed along the axial direction. The outer heat transfer member 92 is a curved plate made of a material having excellent heat conductivity such as aluminum or copper.

  As shown in FIG. 1, a heat insulating material 10 is provided so as to cover the conductor tube 2, the preheating tube 6, and the heat transfer member 9 in the superheated steam generator 100. In addition, the heat insulating material is not illustrated in FIG.

  The heat insulating material 10 is provided so as to fill the space inside the outer iron core 41 between the holding members 7. Specifically, between the inner induction coil 51 and the inner preheating pipe 61, between the inner preheating pipe 61 and the inner heat transfer member 91, between the inner heat transfer member 91 and the inner pipe element 21, and the inner pipe element 21. Between the outer tube element 22, between the outer tube element 22 and the outer heat transfer member 92, between the outer heat transfer member 92 and the outer preheat tube 62, between the outer preheat tube 62 and the outer induction coil 52, In addition, it is provided to fill the space of each part.

<2. Effects of this embodiment>
According to the superheated steam generator 100 configured as described above, the heat transfer member 9 is provided along the winding axis direction of the conductor tube 2 in at least one of the radially inner side or the radially outer side of the conductor tube 2. The temperature distribution in the axial direction of the peripheral members (the inner heat transfer member 91 and the outer heat transfer member 92) of the conductor tube 2 can be reduced. As a result, the temperature of the inner heat transfer member 91 and the outer heat transfer member 92 can be lowered in the vicinity of the superheated steam outlet of the conductor tube 2, so that the amount of heat insulating material 10 used can be reduced. Further, by reducing the amount of the heat insulating material 10 used, the device 100 can be reduced in size and the material cost can be reduced.

  Since the inner heat transfer member 91 and the outer heat transfer member 92 are provided substantially over the circumferential direction, the temperature distribution in the circumferential direction can be reduced. Moreover, since the outer heat transfer member 92 is provided so as to surround the conductor tube 2, the volume of the outer heat transfer member 92 can be increased without difficulty, and the heat transfer effect can be enhanced. Further, since the outer heat transfer member 92 surrounds the conductor tube 2 that is a heat source, heat leaking from the conductor tube 2 to the outside can be confined inside.

  Moreover, since the inner side preheating pipe 61 and the outer side preheating pipe 62 are provided on both sides in the radial direction of the conductor tube 2, the steam can be preheated using the heat leaked to the outside from the conductor tube 2. That is, water vapor can be efficiently heated by reducing loss due to heat radiation from the conductor tube 2. Moreover, since the function which interrupts | blocks the heat | fever leaked to the radial direction both sides from the conductor pipe 2 is exhibited, the usage-amount of the heat insulating material 10 can be reduced. Further, the temperature distribution can be reduced near the conductor tube 2, and the water vapor flowing through the inner preheating tube 61 and the outer preheating tube 62 can be heated by the temperature made uniform by the heat transfer member 9.

<3. Modified Embodiment of the Present Invention>
The present invention is not limited to the above embodiment.
For example, although the conductor tube 2 of the above embodiment has a double tube structure, it may have a quadruple tube or an even-numbered tube element of even more. In this case, each two pipe elements are connected by connecting pipe elements. For example, it can be considered that a plurality of concentric circular conductor tubes 2 according to the above embodiment are arranged.

  The heat transfer member of the above embodiment is a C-shaped curved plate, but may be a heat pipe or a heat plate having a jacket chamber in which a gas-liquid two-phase heat medium is enclosed. There may be. In addition, it is good also as a structure which has arrange | positioned the several metal plate which consists of a metal excellent in thermal conductivity in the circumferential direction.

  The conductor tube 2 of the above embodiment is made of a single material, but may be made of a plurality of materials. For example, as shown in FIG. 9, the conductor tube 2 may be formed of different metals in the upstream portion 2x and the downstream portion 2y. Here, it is conceivable that the conductor tube 2 is divided into two in the winding axis direction and divided into an upstream portion 2x and a downstream portion 2y. If it is this structure, the material selection according to the temperature of the upstream part 2x of the conductor pipe 2 and the temperature of the downstream part 2y can be performed, the rational design of the conductor pipe 2 is attained, and the conductor pipe 2 of Material costs can be reduced. FIG. 9 shows an example in which both the inner tube element 21 and the outer tube element 22 are formed of different metals in the upstream portion 2x and the downstream portion 2y.

  Specifically, it is conceivable that the heat-resistant temperature of the metal forming the upstream portion 2x is made lower than the heat-resistant temperature of the metal forming the downstream portion 2y, and the upstream portion 2x is made of general-purpose alloy steel. It is possible to form from the steel (for example, SUS304, SUS316 etc.), and to form the downstream part 2y from Inconel which is super heat resistant steel.

  At this time, it is conceivable to connect the upstream portion 2x and the downstream portion 2y by welding. Thereby, while simplifying the structure of the conductor pipe | tube 2, the manufacturing cost can be reduced. Here, in order to avoid the damage and deterioration by the high temperature of the welding location 2z, the welding location 2z can also be provided in the low temperature side. That is, the upstream portion 2x is shortened and the downstream portion 2y is lengthened.

  In the said embodiment, although it was the structure which has the three outer side iron cores 41, it is good also as a structure which has the two outer side iron cores 41, as shown in FIG. In this case, the two outer iron cores 41 are provided facing both sides so as to sandwich the inner iron core 3. In this case, it is conceivable that the yoke core 42 is configured by, for example, deforming an annular wound core in a straight line.

  A plurality of the superheated steam generators 100 according to the embodiment may be used and the conductor tubes 2 may be connected in series. In this case, it is conceivable that the steam introduced from the outside is connected by piping so as to flow into the conductor pipes 2 of the respective superheated steam generators 100 after passing through the preheating pipes 6 of all the superheated steam generators 100.

  The superheated steam generator is not limited to the configuration of the above-described embodiment, and may be a configuration in which a conductor pipe is attached to a leg iron core constituting a Scott transformer, and the conductor pipe is heated by induction heating. In this case, the leg iron cores constituting the Scott transformer are three-legged iron cores, and it is conceivable that a conductor tube is attached to each of the leg iron cores located on both sides thereof.

  Furthermore, as a heating method of the superheated steam generator, in addition to the induction heating method as in the above-described embodiment, an electric heating method of generating Joule heat by flowing a current directly through a spirally wound conductor tube is used. Also good.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Superheated steam generator 2 ... Conductor tube 21 ... Inner tube element 22 ... Outer tube element 3 ... Inner iron core 4 ... Magnetic path formation part 41 ... Outer iron core 42 .. yoke core 5 ... induction coil 6 ... preheating pipe 61 ... inner preheating pipe 62 ... outer preheating pipe 9 ... heat transfer member 91 ... inner heat transfer member 92 ... outer side Heat transfer member 2x ... Upstream part 2y ... Downstream part

Claims (10)

A superheated steam generator that generates superheated steam by heating steam flowing in the conductor pipe by induction heating or energizing heating of a spirally wound conductor pipe,
A heat transfer member provided along the winding axis of the conductor tube in at least one of the radially inner side or the radially outer side of the conductor tube;
A superheated steam generator, comprising: a heat insulating material provided to cover the conductor tube and the heat transfer member.   The superheated steam generator according to claim 1, wherein the heat transfer member is provided in a circumferential direction.   The superheated steam generation device according to claim 1 or 2, wherein the heat transfer member is provided so as to surround the conductor tube on a radially outer side of the conductor tube. An inner iron core provided inside the conductor tube;
A magnetic path forming portion that is provided outside the conductor tube and forms a closed magnetic path with the inner iron core;
An induction coil provided between the inner iron core and the magnetic path forming portion, and generating magnetic flux inside the inner iron core;
Provided between the inner iron core and the magnetic path forming part, provided with a preheating tube through which the water vapor flows,
The preheating tube is connected to the conductor tube;
The superheated steam generation device according to any one of claims 1 to 3, wherein the steam is configured to flow in the conductor pipe after flowing through the preheating pipe.   The said preheating pipe | tube contains the outer side preheating pipe | tube provided between the said conductor pipe | tube and the said magnetic path formation part, and the inner side preheating pipe | tube provided between the said conductor pipe | tube and the said inner iron core. Superheated steam generator.   The heat transfer member includes an outer heat transfer member provided between the conductor tube and the outer preheat tube, and an inner heat transfer member provided between the conductor tube and the inner preheat tube. Item 6. The superheated steam generator according to Item 5.   The superheated steam generating device according to any one of claims 1 to 6, wherein the conductor pipe is formed of different metals in an upstream portion and a downstream portion.   The superheated steam generator according to claim 7, wherein a heat resistant temperature of the metal forming the upstream portion is lower than a heat resistant temperature of the metal forming the downstream portion.   The superheated steam generator according to claim 7 or 8, wherein the upstream portion and the downstream portion are connected by welding. The upstream portion is formed of stainless steel;
The superheated steam generator according to any one of claims 7 to 9, wherein the downstream portion is formed of Inconel.