JPH08145282A - Heat insulation structure of internal part of extendable tube for high temperature - Google Patents

Abstract

PURPOSE: To provide a light weight structure without generation of cracking or coming off and less in heat accumulation and heat radiation. CONSTITUTION: In a heat insulation structure of the internal part of an extendable tube 1 having a fireproof material inside the extendable tube 1, a sheet of inorganic fibers is bent alternately at a specified width to have an accordion-like inorganic fiber block 4, on the rear face thereof, support fittings 2 divided up and down into two to be able to extendable in the length direction and disposed inside the tube 1 is mounted and the block 4 is arranged inside the tube 1 through the fittings 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal heat insulating structure for a high temperature expansion tube provided in the middle of a pipeline for supplying a high temperature fluid such as high temperature air or combustion gas.

[0002]

2. Description of the Related Art In a steel plant, a chemical plant, etc., an expansion pipe is arranged in the middle of a pipe for feeding a high temperature fluid so that the pipe can absorb thermal expansion. . The temperature of the fluid passing through this pipe is 300 to 400 ° C.
Because of the high temperatures mentioned above, the interior of the expansion tube is lined with a fireproof heat insulating material to maintain its strength and reduce the amount of heat dissipated. FIG. 7 shows a typical example of the conventional internal heat insulating structure of the expansion tube for a high temperature fluid. As shown in the drawings, a holding metal fitting called a stud 13 is appropriately arranged on the inner surface of the expansion tube, and has a heat insulating structure in which one or more castable layers 15 are provided. Further, as shown in FIGS. 1 and 2, as another heat insulating structure, there is also a structure in which one or more layers of ceramic fibers 16 are provided by appropriately installing stud pins 14 on the inner surface of the expansion tube.
The use of a block formed by continuously folding an inorganic fiber blanket in an accordion shape as a lining material for a furnace is described in Japanese Utility Model Publication No. 61-46396.

[0003]

However, when the internal heat-insulating structure is formed by castable, due to the structure, the specific gravity of the castable itself is large, so that the strength of the stud and the expansion tube main body is strong enough to withstand the weight of the castable. Therefore, there is a drawback in that the weight of the expansion tube main body is increased. In addition, cracks are likely to occur due to expansion and contraction due to the thermal behavior of the expandable tube and slight vibration of the pipeline system, which may cause the castable to partially or completely fall off, and further, collapse due to thermal spalling. is there. The construction of castables is to knead and build powder of refractory material and water.
In order to dry by heating and exhibit a predetermined strength, heating and drying work is required after building. This requires a facility for temperature rising drying, and may require several days for temperature rising drying, and in the case of long time, 10 days or more, which makes it difficult to shorten the construction period. On the other hand, in the structure in which the ceramic fiber is arranged on the inner surface, the surface of the ceramic fiber gradually separates and scatters as the fluid passes, and this phenomenon becomes remarkable especially when the fluid becomes high speed, and the life is greatly extended. Not only is it shortened, but the separated ceramic fiber powder (shot) is mixed in the passing fluid. In addition, when the ceramic fiber structure is used, the tip of the stud pin is exposed to the internal fluid, and therefore an expensive material such as heat resistant steel must be used. Furthermore, when the size of the expansion tube is large, the number of stud pins installed is considerable, and the heat loss from the stud pins is also large. INDUSTRIAL APPLICABILITY The present invention eliminates the above-mentioned drawbacks of the conventional high-temperature expansion tube, and the heat insulating material inside can freely follow the expansion and contraction of the expansion tube, has excellent heat insulation, has an extremely small amount of heat dissipation, and is lightweight. The present invention also provides a high temperature expansion tube having a simple structure.

[0004]

According to the present invention, a sheet-shaped inorganic fiber is alternately bent in a predetermined width in an internal heat insulating structure of a stretchable tube in which a refractory material is disposed inside the stretchable tube. An accordion-shaped inorganic fiber block, and a support metal fitting on the back surface of this inorganic fiber block for arranging inside the expansion tube, which is divided into two or more so as to be expandable and contractible in the length direction. Along with attaching
This is an internal heat insulating structure for a high temperature expansion tube, characterized in that a fiber block is arranged inside the expansion tube via this support fitting. On the surface of the inorganic fiber block that comes into contact with the high-temperature fluid flowing inside the high temperature expansion tube, the inorganic fiber block is folded into a narrow area so that a sheet made of heat-resistant steel yarn spun on the molded inorganic fiber appears on the surface. It is advantageous to wear or cover the surface of the inorganic fiber block with a ceramic plate. As the inorganic fiber, glass fiber, rock wool, ceramic fiber or the like can be used, but ceramic fiber is superior from the viewpoint of heat resistance. These are used in the form of sheets.

[0005]

[Operation] The inorganic fibers continuously folded in an accordion shape are compression-molded to form a block, and the continuous fold in the accordion shape is made to coincide with the expansion / contraction direction of the expansion tube main body,
The internal heat insulating material can freely follow the expansion and contraction of the expansion tube. Further, since the heat insulating material is fibrous, it is lightweight, and does not cause cracks or fall off due to thermal spalling or slight vibration of the pipeline. Further, the heat storage amount is small, and the heat dissipation amount is small, so that the energy efficiency is extremely good, and the heating and drying equipment and work are unnecessary.

[0006]

FIG. 1 is a perspective view showing a first embodiment of the present invention,
2 is a side view showing a first embodiment of the present invention, FIG. 3 is a sectional view thereof, FIG. 4 is an enlarged perspective view of a partial cutout thereof, and FIGS. 5 and 6 are partial sectional perspective views of different embodiments. 7 and 8 are partial cross-sectional views of another conventional example. In the figure, 1
Is the main body of the expansion tube fitting, which is located on both the inlet side and the outlet side, and has the expandable bellows 2 between them. An inorganic fiber block 4 is disposed inside to protect the bellows 2 from heat. The inorganic fiber block 4 has an accordion shape by alternately bending sheet-shaped inorganic fibers such as a blanket into a predetermined width, and a channel 5 serving as a support fitting is attached to the back surface of the inorganic fiber block 4. Here, the surface of the inorganic fiber block 4 refers to the surface on the side that comes into contact with the high-temperature fluid, the back surface refers to the surface on the opposite side, and the length direction refers to the direction between the expansion tube fitting bodies. The inorganic fiber blocks 4 are laminated in the accordion shape in the vertical direction. Although any method can be adopted as a method of attaching the channel 5 to the inorganic fiber block 4, as shown in FIGS. 3 and 4, the beam 6 is passed through the inside of the fold of the inorganic fiber block 4 in the lateral direction, It is advantageous to attach the approximately middle portion and the channel 5 by coupling with a coupling fitting. At this time, the beam and the joint fitting may be integrated into a substantially T-shape, and the leg portion serving as the joint fitting may penetrate the inorganic fiber sheet and fit into the channel 5 at a predetermined position. The number of this beam may be one for one channel, but if it is two or more, the intensity is further improved. The channel 5 is a support metal fitting for disposing the inorganic fiber block 4 in the expansion tube, and the inorganic fiber block is divided into two or more pieces so that the inorganic fiber block can be expanded and contracted according to the length method. In FIGS. 1 to 3, two channels are attached to the inorganic fiber block 4 with a predetermined gap. Then, two beams 6 are coupled to each channel 5 through coupling metal fittings, and the inorganic fiber block 4
And channel 5 are integrated. Here, since the channel 5 is divided into two, it is possible to expand and contract in the length direction. Since the inorganic fiber block 4 is often packed and attached in a compressed state, it is preferable to place a gap such that the two channels do not overlap each other during the compression. The compression rate at this time is 30
% Is appropriate. The inorganic fiber block 4 is attached to the expandable tube via a channel 5 which is a support fitting, as shown in FIGS. Although the mounting method is arbitrary, in this drawing, the mounting bolt 7 welded to the horizontal portion of the expansion tube metal fitting body 1 penetrates the bolt hole provided in the channel 5 which is the support metal fitting of the inorganic fiber block 4, and there, It is integrated by a nut. In the drawing, one place is integrated with mounting bolts, but 2
If it is more than the number of places, it becomes stronger. Further, although the expansion tube fitting body 1 is on both sides, in the drawing, one channel 5 of the inorganic fiber block 4 is integrated into one side and the other channel 5 of the inorganic fiber block 4 is integrated into the other side so that the expansion tube inside In addition to covering the surface, it is elastic in the length direction. When the width and length of the expandable tube are larger than the size of the inorganic fiber block 4, a large number of fiber blocks 4 can be combined and used as shown in FIG. Further, if necessary, it is preferable to fill the space formed between the bellows of the expansion tube and the fiber block 4 with a park or a blanket of inorganic fibers.
It is preferable to fill so as to be about / m ³ .

FIG. 5 shows another embodiment, in which the inorganic fiber block 4 is formed into a sheet shape, and the inorganic fiber block is narrowed in the bent portion of the inorganic fiber block so that a sheet formed by weaving inorganic fibers with heat-resistant steel yarn appears on the surface. I wore it. This may be performed on the entire surface of the inorganic fiber block 4, or only a weak portion such as a joint between the inorganic fiber blocks in terms of strength. By doing so, damage to the block due to the flow of the fluid passing through the inside and damage to the block due to dust, scale, etc. can be reduced.

FIG. 6 shows still another embodiment, in which the surface of the inorganic fiber block 4 is covered with a ceramic plate. This is also an inorganic fiber block 4
May be performed over the entire surface, or only a weak portion such as a joint between the inorganic fiber blocks in terms of strength. The ceramic plate may be attached to the inorganic fiber block 4 by any method, but in the drawing, the ceramic bolt 10 attached to the channel 5 is penetrated to the ceramic plate 9 placed on the surface of the block 4, and then the ceramic washer 11 is provided there. It is fastened with a ceramic nut 12 through. At this time, at least one of the bolt holes provided in the ceramic plate 9 is allowed to freely expand and contract in the length direction.
One is formed in a shape having a predetermined width in the length direction of the block, and is fixed by a nut 12 so that each bolt can slide in the length direction of the block. By doing so, damage to the block due to the flow of the fluid passing through the inside and damage to the block due to dust, scale, etc. can be reduced. Further, since the ceramic plate has excellent heat resistance, it is also excellent for high temperatures.

[0009]

In summary, according to the present invention, the following excellent effects are exhibited. (1) By folding a blanket-shaped fiber in an accordion manner and aligning it with the direction of expansion and contraction, the heat insulating material inside can freely follow the expansion and contraction of the expansion tube. (2) Since the heat insulation is excellent, the amount of heat dissipated is extremely small, and the amount of heat storage is also small, resulting in a large energy saving effect. (3) Light weight because the fiber material is molded into blocks,
Moreover, the structure is simple and the construction is extremely easy. (4) Since it is an inorganic fiber, there is no need for equipment and work involved in temperature rising drying. (5) There is no occurrence of thermal spalling or cracking due to slight vibration of the pipeline.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment according to the present invention.

FIG. 2 is a side view showing a first embodiment according to the present invention.

FIG. 3 is a cross-sectional view of FIG. 2 taken along the plane AA.

FIG. 4 is a partially enlarged view of FIG.

FIG. 5 is a partial sectional view showing the second embodiment.

FIG. 6 is a partial sectional view showing another embodiment.

FIG. 7 is a sectional view showing a conventional example.

FIG. 8 is a cross-sectional view showing another conventional example.

[Explanation of symbols]

 1 ・ ・ Expansion pipe hardware 2 ・ ・ Bellows 3 ・ ・ Fibrous refractory material 4 ・ ・ Fibrous refractory block 5 ・ ・ Channel 6 ・ ・ Beam 7 ・ ・ Mounting bolt 8 ・ ・ Fibrous refractory cloth 9 ・ ・Ceramic plate 10-Ceramic bolt 11-Ceramic washer 12-Ceramic nut 13-Stud 14-Stud pin 15-Castable 16-Ceramic fiber

Claims (3)

[Claims] 1. An accordion-shaped inorganic fiber block obtained by alternately bending sheet-shaped inorganic fibers in an accordion-shaped inorganic fiber block in an internal heat insulation structure of the expansion tube in which a refractory material is arranged inside the expansion tube. On the back surface of this inorganic fiber block, a support metal fitting for arranging inside the expansion tube, which is divided into two or more pieces so as to be expandable and contractible in the length direction, is provided. An internal heat insulation structure for a high temperature expansion tube, characterized in that an inorganic fiber block is disposed inside the expansion tube via the. 2. The high temperature according to claim 1, wherein the inorganic fiber block is sandwiched between the bent portions of the inorganic fiber block so that a sheet formed by weaving inorganic fibers formed into a sheet with heat-resistant steel yarn appears on the surface. Insulation structure for expansion tube. 3. The internal heat insulating structure for a high temperature expansion tube according to claim 1, wherein the surface of the inorganic fiber block is covered with a ceramic plate.