JPH0518579Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the structure of a double cylinder for high temperature fluid used in a chimney, and more particularly to the structure of the bent part of the double cylinder for high temperature fluid in a multi-legged chimney.

[Conventional technology]

Generally, gas (exhaust gas) emitted during furnace operation in a factory or the like is discharged into the sky through a chimney.

In particular, in the case of a chimney in a factory, the exhaust port must be located as high as possible in order to exhaust the exhaust gas as high as possible in the sky. Therefore, it is necessary to have a chimney of sufficient height. When a tall chimney is provided, it is required to have structural reliability of the chimney and to suppress construction costs.

In response to these demands, there is a so-called multi-legged chimney, which aims to strengthen the structure at low cost by assembling multiple chimneys together.

On the other hand, the exhaust gas passing through the chimney is usually extremely hot. As a result, the inside surface of the chimney, which comes into contact with the exhaust gas, also becomes extremely hot. On the other hand, the outside surface of the chimney comes into contact with the outside air and is cooled by the outside air, so
The temperature difference between the inside and outside of the chimney increases, and thermal stress due to this temperature difference acts on the chimney. Such thermal stress causes deformation or damage to the chimney, but in order to prevent the occurrence of such thermal stress, it has been considered to make the chimney have a double-tube structure.

[Problem that the invention attempts to solve]

Incidentally, even in the above-mentioned multi-legged chimney, the chimney is required to have a double-tube structure in order to prevent the generation of thermal stress.

However, in a multi-legged chimney, there is a bend between the chimney legs that spread outward and the upper part of the chimney that is gathered together. There is a problem.

In other words, when a chimney is normally made to have a double-tube structure to prevent the occurrence of thermal stress, an inner tube and an outer tube are provided, and
Since the inner cylinder undergoes thermal expansion due to contact with high-temperature fluid, the inner cylinder must be able to slide in the axial direction relative to the outer cylinder.

However, if there is a bend in the chimney, at this bend the inner cylinder, which has expanded greatly, is deformed within the outer cylinder, which hardly expands. This causes the inner cylinder to come into contact with the inner surface of the outer cylinder, generating large stress between the inner cylinder and the outer cylinder.
There is a risk of damage to the inner and outer cylinders and even the collapse of the chimney.

The present invention attempts to solve the above-mentioned problems by preventing the inner cylinder from coming into contact with the outer cylinder at the bent part even if the inner cylinder expands thermally, thereby preventing damage or collapse of the chimney. It is an object of the present invention to provide a bent part structure of a double cylinder for high temperature fluid in a multi-legged chimney that can eliminate the fear.

[Means for solving problems]

Therefore, the bent structure of the double cylinder for high-temperature fluid in the multi-legged chimney of the present invention is such that the outer cylinder is inclined toward the center axis of the multi-legged chimney, and the same An inner cylinder for high-temperature fluid is provided which is separated from the outer cylinder and arranged substantially coaxially, and a support portion for supporting the inner cylinder with the outer cylinder is provided at a bent portion between the outer cylinder and the inner cylinder. The supporting portion is disposed only on the central axis side, and is configured to support the inner cylinder by the outer cylinder while preventing interference with the outer cylinder due to thermal expansion of the inner cylinder. It is characterized by being comprised of a support plate provided on the outer peripheral surface and a bearing pressure plate provided on the inner peripheral surface of the outer cylinder so as to slidably receive the support plate in surface contact.

[Effect]

In the bent part structure of the double cylinder for high temperature fluid of the present invention described above, when the inner cylinder contacts the high temperature fluid in the inclined outer cylinder and thermally expands, the above-mentioned The support plate provided on the outer peripheral surface of the inner cylinder is supported by the bearing pressure plate provided on the inner peripheral surface of the outer cylinder in surface contact and slides stably on the bearing pressure plate, so that the inner cylinder Thermal expansion occurs along the outer cylinder without contacting the outer cylinder. Further, even when high temperature fluid does not flow into the inner cylinder, the support plate is supported by the bearing pressure plate at the bent portion, so the inner cylinder is supported by the outer cylinder.

〔Example〕

The structure of the bent part of the double tube for high temperature fluid in a multi-leg chimney as an embodiment of the present invention will be explained below with reference to the drawings. Fig. 1 is a horizontal sectional view thereof;
Figure 2 is a horizontal sectional view (enlarged view of Figure 1) showing the details of each support part, and Figure 3 is a schematic diagram of a double cylinder with bent parts in a multi-legged chimney equipped with this structure. The vertical sectional view, FIG. 4, is an enlarged view of a portion of FIG. 3.

As shown in Figure 3, the double pipe S with the bent part in the multi-legged chimney equipped with this structure has one set of components that make up the multi-legged chimney, and the center of the multi-legged chimney is The outer cylinder 1 is provided with an outer cylinder 1 inclined toward the axis CL, and an inner cylinder 2 for high-temperature fluid disposed approximately coaxially with the outer cylinder 1 and spaced apart from the outer cylinder 1 by an appropriate length inside the outer cylinder 1.

This double cylinder S is set to be inclined toward the central axis CL of the multi-legged chimney over almost its entire length (excluding the vicinity of the tip). Moreover, the degree of inclination of the double cylinder S toward the central axis CL increases as it goes downward, except for the vicinity of the tip.

Therefore, in the part where the degree of inclination of the double cylinder S changes, there are a first bent part 15, a second bent part 16, and a third bent part 15.
A bent portion 17 is formed. However, bending part 1
Only 7 is bent so as to be convex outward. With these bent portions 15, 16, 17, each part of the double cylinder S is divided into a first inclined part 18, a second inclined part 19, a second inclined part 19,
It can be divided into a third slope part 20 and a fourth slope part 21.

Each bent portion 15, 16, 17 is provided with a support portion 11, 13, 14. Further, although it is not a bent part, a support part 12 is also provided at a substantially central part in the axial direction of the second inclined part 19. , a third support part 13, and a fourth support part 14.

A plurality of such support parts 11 to 14 (three in this embodiment) are provided, and all of them are provided only in the direction in which the double cylinder S falls, that is, on the CL side.

As shown in FIG.
and a bearing pressure plate 8 provided on the outer cylinder 1 to slidably receive the bearing plate 9 in surface contact.

The details of each of the support parts 11 to 14 are as shown in FIG. The surface is aligned so as to come into surface contact with the inner surface of the bearing pressure plate 8 fixed to the inner circumferential surface of the outer cylinder 1. In this embodiment, both the outer surface of the support plate 9 and the inner surface of the pressure plate 8 are formed into flat surfaces that are easy to process.

Further, on the inner circumferential surface of the outer cylinder 1, on both left and right sides of the bearing pressure plate 8, lateral movement prevention plates 7 are provided at required intervals from the bearing pressure plate 8 and the bearing plate 9, respectively. It is provided to protrude along the axial direction.

Note that an annular stiffener 2a is arranged approximately horizontally on the outer periphery of the inner cylinder 2.

In addition, in this embodiment, each support portion 11, 13, 1
4 is provided directly below each bent portion 15 , 16 , 17 , that is, at the upper end of each inclined portion 18 , 19 , 20 , so that the matching surface of the bearing pressure plate 8 and the supporting plate 9 is aligned with each inclined portion of the inner cylinder 2 . It is set along the thermal expansion direction in 18, 19, 20, that is, along the axial direction of each inclined portion 18, 19, 20.

Furthermore, as shown in FIG. 3, a support portion 10 is provided at the base of the outer cylinder 1 and the inner cylinder 2 in this embodiment, so that the outer cylinder 1 supports the inner cylinder 2 in the vertical direction.

As shown in FIG. 4, this support part 10 has a ring 3 provided on the inner periphery of the outer cylinder 1 and a ring 5 provided on the outer periphery of the inner cylinder 2. Planar horizontal part 3a and cylindrical vertical part 3
It is equipped with b.

The horizontal part 5a of the ring 5 is fixed on the horizontal part 3a of the ring 3, and furthermore, the horizontal part 5a of the ring 5 is
Both the inner circumferential surface and the outer circumferential surface of the inner tube 2 are fixed to each other, and the inner tube 2 is fixed to the outer tube 1 at this support portion 10 .

As a result, the support part 10 serves as a fulcrum of the inner cylinder 2 with respect to the outer cylinder 1, so that both the outer cylinder 1 and the inner cylinder 2 have sufficient strength and rigidity in the vicinity of the support part 10. In addition, ring 3 and ring 5
are also reinforced by ribs 4 and 6, respectively.

Further, the distance between the outer cylinder 1 and the inner cylinder 2 as shown in FIG. 3 is set to an appropriate size in consideration of the thermal expansion of the inner cylinder 2. Since the upper end portion of the heavy cylinder S (fourth inclined portion 21, etc.) is affected by thermal expansion extremely, the distance between the outer cylinder 1 and the inner cylinder 2 is set to be large.

Furthermore, the inner cylinder 2 of this embodiment absorbs its own weight due to the inclination in the CL direction by supporting the outer cylinder 11 through each of the supporting parts 11 to 14.
In particular, the dead weight of the inner cylinder 2 supported by the outer cylinder 1 cancels the deformation of the inner cylinder 2 that occurs when the inner cylinder 2 is thermally expanded by the high-temperature fluid flowing inside the inner cylinder 2. It is set as follows.

In other words, when the inner cylinder 2 thermally expands, the first
Due to the expansion of the inclined part 18, the inclined parts 19 to 21 above the first inclined part 18 tend to rotate around the second support part 12. This rotation works to move inward (in the CL direction) below the second support part 12 and outward (in the opposite direction to CL) above the second support part 12. (direction in which the upper end of the inner cylinder 2 falls toward the CL side). Therefore, if the shape of the inner cylinder 2 is restrained in advance by the outer cylinder 1 before the expansion of the inner cylinder 2 so that the inner cylinder 2 has a shape that deforms due to its thermal expansion, the inner cylinder 1 can be deformed. Thermal deformation of the inner cylinder 2 is allowed.

The bearing load of the inner cylinder 2 in each of the bearing parts 11 to 14 is calculated based on the self-weight deformation and thermal expansion deformation of the inner cylinder 2 while taking into account the deformation inside the outer cylinder 1 predicted by the thermal expansion of the inner cylinder 2. are set so that they cancel each other out.

A plurality of double cylinders S thus formed are assembled to form a multi-legged chimney.

Since the bent part structure of the double tube for high temperature fluid in the multi-legged chimney as an embodiment of the present invention is configured as described above, when the double tube S is used, the inside of the inner tube 2 is heated by high temperature fluid such as exhaust gas. Fluid passes through it. Therefore, the inner cylinder 2 is heated by the high-temperature fluid and thermally expands.

That is, the inner cylinder 2 expands upward using the support portion 10 as a fulcrum, and smoothly extends upward at the first bending portion 15 by the first support portion 11 . This results in
A moment of rotation to the left in the figure is applied to the second inclined portion 19 around the second support portion 12 .

This moment acts in a direction that causes the inner cylinder 2 to stand up above the first bent portion 15 (in the opposite direction to CL), but the load on the inner cylinder 2 is applied in advance in a direction that causes the inner cylinder 2 to fall down (in the CL direction). Therefore, since the above moment is canceled by its own weight, the tilting of the inner cylinder 2 in the direction opposite to CL is actually extremely small.

At this time, in each of the support portions 11, 13, and 14, the reaction force for supporting the weight of the inner cylinder 2 decreases and becomes zero or close to zero.

For this reason, the third inclined portion 20 and the fourth inclined portion are largely influenced by the thermal expansion of the inner cylinder 2 which is far away from the support portion 10.
The inclined portion 21 is also prevented from being deformed in the direction opposite to CL due to thermal expansion, and contact with the inner circumferential surface of the outer cylinder 1 on the outside of the inner cylinder 2 (in the opposite direction to CL) is avoided.

In addition, the inner cylinder 2 has a second inclined part 19 and a third inclined part 2.
0 and the fourth inclined part 21, but are guided by the respective support parts 12 to 14 and smoothly extend, and in the fourth inclined part 21 near the upper end of the inner cylinder 2 where the amount of extension is large, the inner cylinder Since the clearance between the inner cylinder 2 and the outer cylinder 1 is set large in consideration of this amount of extension, the inner cylinder 2 does not come into contact with the outer cylinder 1.

Note that due to the expansion of the inner cylinder 2, each bent portion 15, 16
In this case, the inner cylinder 2 approaches the outer cylinder 1, but the distance between the inner cylinder 2 and the outer cylinder 1 is set to an appropriate length in consideration of the amount of extension of the inner cylinder 2. The inner cylinder 2 never comes into contact with the outer cylinder 1.

In addition, each of the bearing parts 11 to 14 (especially the first bearing part 1
In 1), as a result of the deformation of the inner cylinder 2 due to thermal expansion, the reaction force of each support part 11 to 14 becomes negative, so that the support plate 9 of each inner cylinder 2 is separated from the bearing pressure plate 8 of the outer cylinder 1. Even if there is a case where each bearing part 11 to 14 is C.
Since it is provided only in the L direction and is free in the direction opposite to CL, a reaction force from the direction opposite to CL does not act, and it is not necessary to consider the generation of stress in the inner cylinder 2 to this extent.

Furthermore, since each of the supporting parts 11 to 14 is provided only on one side (CL direction), there is an advantage that expansion of the inner cylinder 2 in the outer circumferential direction is allowed.

In addition, in this embodiment, each support portion 11, 13, 1
4 was provided directly below the bent portions 15, 16, 17,
It is also conceivable that both the bearing pressure plate 8 and the bearing plate 9 have smooth curved surfaces and each bearing part is provided at a bent part.

[Effect of idea]

As described in detail above, according to the bent part structure of the double cylinder for high temperature fluid in the multi-legged chimney of the present invention, there is a space inside the outer cylinder that is inclined toward the central axis of the multi-legged chimney and is spaced apart from the outer cylinder. and an inner cylinder for high-temperature fluid arranged almost coaxially, and a support part for supporting the inner cylinder with the outer cylinder is provided on the center axis side at a bent part between the outer cylinder and the inner cylinder. located only in
In order to support the inner cylinder by the outer cylinder while preventing interference with the outer cylinder due to thermal expansion of the inner cylinder, the support part is a support plate provided on the outer peripheral surface of the inner cylinder; The simple structure consists of a bearing plate provided on the inner circumferential surface of the outer cylinder so as to slidably receive the bearing plate in surface contact with the bearing plate, so that even if the inner cylinder thermally expands, the outer cylinder remains There is no contact between the inner and outer cylinders, and the outer cylinder supports the inner cylinder in the vertical direction, which reliably prevents damage or collapse of the chimney. A multi-legged chimney can be put into practical use. For this reason,
The multi-legged chimney is low in cost and has good performance, and the double-tube structure adds durability and safety, resulting in an extremely high-performance chimney.

[Brief explanation of the drawing]

Figures 1 to 4 show the structure of the bent part of the double tube for high temperature fluid in a multi-legged chimney as an embodiment of the present invention. Fig. 3 is a horizontal sectional view showing the details of the part (enlarged view of Fig. 1), Fig. 3 is a schematic vertical sectional view of a double cylinder with a bent part in a multi-legged chimney equipped with this structure, Fig. 4 is an enlarged view of the portion of FIG. 3. 1... Outer cylinder, 2... Inner cylinder, 2a... Stiffener, 3
...Ring, 3a...Horizontal part, 3b...Vertical part,
4...Rib, 5...Ring, 5a...Horizontal part, 6
... Rib, 7 ... Lateral movement prevention plate, 8 ... Bearing plate, 9 ... Support plate, 9a ... Leg part, 10 ... Support part, 11 ... First support part, 12 ... Second bearing part,
13...Third support part, 14...Fourth support part, 15
...First bent part, 16... Second bent part, 17...
Third bent part, 18...first inclined part, 19...second
Inclined part, 20... Third inclined part, 21... Fourth inclined part, S... Double tube.

Claims (1)

[Scope of utility model registration request] The multi-legged chimney includes an outer cylinder inclined toward the center axis, and an inner cylinder for high-temperature fluid arranged approximately coaxially with the outer cylinder, spaced from the outer cylinder inside the outer cylinder. At the bent portion between the outer cylinder and the inner cylinder, a support part for supporting the inner cylinder with the outer cylinder is provided only on the central axis side, and interference with the outer cylinder due to thermal expansion of the inner cylinder is prevented. In order to allow the inner cylinder to be supported by the outer cylinder while preventing the above-mentioned damage, the support part slidably receives the support plate in surface contact with a support plate provided on the outer peripheral surface of the inner cylinder. A bent part structure of a double cylinder for high temperature fluid in a multi-legged chimney, characterized in that it is comprised of a bearing plate provided on the inner circumferential surface of the outer cylinder.