JPH03523B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a ceramic hanging rod connection structure that connects two or more ceramic rods in applications where the ceramic rods are suspended.

"Prior art and its problems" In recent years, atmospheric pressure fired products such as silicon carbide and silicon nitrogen have been invented, and with the development of manufacturing technology, their practical use is rapidly progressing. These fine ceramics have excellent properties such as extremely high tensile strength and oxidation resistance even at high temperatures of 1000℃ or higher, almost no creep phenomenon unlike metals, and resistance to thermal shock. It is particularly useful as a structural material used at high temperatures.

Conventionally, when suspending something such as a partition wall from the ceiling of a heating furnace at a high temperature of around 1000 to 1300°C, it was customary to use water-cooled metal pipes as the load-bearing member. . In this case, the outer periphery of the water-cooled metal tube is naturally kept warm to prevent heat loss from the heating furnace, but some degree of heat loss was inevitable. Also, it was not easy to secure a water supply for water cooling.

Recently, a technology has been developed to improve heating efficiency by combining a plurality of air-permeable ceramic members, such as ceramic honeycomb bodies, into a radiant panel, and suspending the panel from the ceiling of a heating furnace, for example. In this case, in order to provide sufficient heat resistance, it is preferable that the hanging rod of the radiant panel is also made of ceramics. This hanging rod has 15 to 40
Although it is subject to a load of approximately Kg and is exposed to an oxidizing atmosphere at a temperature of approximately 1,000 to 1,300°C, a sufficiently long life can be obtained by using the fine ceramics mentioned above.

However, in heating furnaces used for large-scale steel manufacturing, etc., the distance from the furnace ceiling to the object to be heated is long, and in order to place the radiant panel close to the object to be heated, the total length must be over 2 meters. A hanging rod is required. In such a case, if the hanging rod is formed from a single ceramic rod, the following problems will occur. First, the radiant panel is subjected to wind pressure due to the flow of combustion gas in the furnace, and a large bending load is applied to the hanging rod, which may cause it to break. Second, since the hanging rod becomes long, it becomes difficult to attach and detach the radiant panel. Third, fine ceramic rods that are too long are difficult to manufacture.

For this reason, it is preferable for the above-mentioned hanging rod to be one in which a plurality of ceramic rods are connected, but such a connecting structure is required to have the following characteristics. The first point is that the load of the radiant panel can be supported with sufficient margin. The second point is that the work of connecting the hanging rods can be easily done on site. The third point is to withstand wind pressure inside the furnace, earthquakes, and artificial loads during repairs.
The connection part of the hanging rod should be flexible to some extent. In addition, it is desirable that the components be less susceptible to damage due to stress concentration, that the structural members are easy to manufacture, and that the cost is low.

"Object of the Invention" An object of the present invention is to solve the problems of the prior art described above. In other words, it can support large loads, and allows for easy connection of hanging rods.
To provide a connecting structure for ceramic hanging rods in which the connecting part is flexible to some extent, the constituent members are easy to manufacture, and the cost is low.

"Structure of the Invention" The connecting structure of ceramic hanging rods according to the present invention is such that a long through hole is formed in the end of a pair of ceramic hanging rods to be connected in the axial direction of the rods, and the through hole is inserted into each of the through holes. A pair of plate-shaped engagement members, and link members hooked to protrusions provided on both sides of each of the engagement members, and the through hole of the ceramic hanging rod of the engagement member. The contact portion side is characterized by being formed in a convex arc shape when viewed from the plate-like wide surface side.

Therefore, by inserting the plate-shaped engaging members into the long through holes at the ends of the pair of ceramic hanging rods, and hooking the link members to the protrusions on both sides of the engaging members, it can be easily operated. Ceramic hanging rods can be connected, and since the ceramic hanging rods are connected via the link material and the engaging member that supports the load with a swollen inner arc-shaped surface, the connected ceramic hanging rods can be connected in the lateral direction. When a force of 2 is applied, the connecting portion can be bent to some extent, and excessive bending stress can be avoided on the ceramic hanging rod. Furthermore, since the connecting structure and the structure of the component parts are relatively simple, manufacturing is easy and the cost can be reduced. Furthermore, since there is no need for any means such as gluing, folding, or screwing, it is easy to assemble as well as disassemble.

Further, the through hole is a long hole extending in the axial direction of the ceramic hanging rod, and the engaging member is a plate-shaped body. In this way, the engagement member is a plate-shaped body,
By arranging the ceramic hanging rod along the axial direction, the ceramic rod provided with the through holes can sufficiently withstand tensile loads. In other words, the tensile load supported by the connecting portion can be made close to the tensile load supported by the ceramic hanging rod itself, so that almost no reduction in strength due to the connecting portion occurs. This also leaves room for the ceramic hanging rod and the engaging member to be made smaller and lighter.

Further, a contact portion of the inner surface of the through-hole of the ceramic hanging rod with the engaging member is formed in a concave arc shape when viewed from the opening side of the through-hole, and the contact portion with the through-hole of the engaging member and a contact portion with the link member that has a cross-sectional shape taken in a direction perpendicular to the plane of the flat plate is formed in a bulging arc shape, and a contact portion of the engagement member with the through hole. Since the radius of curvature of the bulging arc is smaller than the radius of curvature of the concave arc of the through hole, the movement of the plate-shaped engagement member becomes smoother, and the load is not supported by the edge portion that is prone to chipping. Corner chipping is less likely to occur, further increasing the reliability of the connecting portion.

``Embodiments of the Invention'' FIG. 3 shows an example in which the connecting structure of ceramic hanging rods according to the present invention is applied to a hanging structure of a radiant panel. That is, the ceiling 11 of the heating furnace
The ceramic hanging rods 12, 12 are suspended and supported from the ceramic hanging rods 12, 12.
Another ceramic rod is suspended from the lower end of the
are connected by connecting portions 14, 14, respectively. The ceramic hanging rods 13, 13 are inserted through horizontal support frames 15, 16, and their lower ends are fixed to the support frames 16. In addition, the horizontal support frame 1
A plurality of vertical support frames 17 are arranged between 5 and 16 at predetermined intervals, and the ceramic honeycomb body 18 is assembled into a panel shape by these support frames 15, 16, and 17. There is. The radiant panel made in this way is made of ceramic hanging rods 1
2 and 13, the heating efficiency can be increased by irradiating the heated object with the heat absorbed by convection heat transfer from the high-temperature atmospheric gas as radiant heat.

1 and 2 show the main parts of the connecting portion 14. As shown in FIG. A through hole 21 is formed at each end of the ceramic hanging rods 12 and 13 to be connected. As shown in FIGS. 4 and 5, the through hole 21 is elongated with a width a along the axial direction of the ceramic hanging rod 12, and its upper and lower ends are in the shape of a concave arc when viewed from the side. is doing. The same applies to the ceramic hanging rod 13. An engaging member 22 is inserted through the through hole 21 . As shown in FIGS. 6 and 7, the engaging member 22 is made of a ceramic plate having a thickness b smaller than the width a of the through hole 21, and has a tapered round shape as shown in FIG. It has a tip 23 formed in a bulged arc shape with a border, a side 24 facing the tip 23 at a distance c, and protrusions 25 formed on both sides of the side 24. As seen in Figure 7, the tip 2
3 is also formed in an arc shape when viewed from the side, and the arc has a smaller radius of curvature than the arc at the end of the through hole 21. Thereby, when the tip portion 23 comes into contact with the end portion of the through hole 21 under load, the Hertzian stress does not become excessive and corner chipping can be prevented. Both end portions of a pair of link plates 26, 26, which are link members, are hooked onto the protrusions on both sides of the engaging member 22. Note that when the link plate 26 is hooked, the protrusion 25 of the engagement member 22 prevents it from coming off. As shown in FIGS. 8 and 9, the link plate 26 is made of a ceramic plate and has round holes 27, 27 formed at both ends thereof. Then, by inserting the protrusions on both sides of the engaging member 22 into the round holes 27, the link plate 2
6 is hooked onto the engaging member 22. in this case,
By making the side cross section of the side 24 of the engaging member 22 arc-shaped, Hertzian stress at the contact portion between the inner periphery of the round hole 27 and the side 24 can be prevented from becoming excessive.

In the above configuration, the ceramic hanging rod 1
2 and 13 are connected via an engaging member 22 and a link plate 26. Therefore, the connecting portion 14
Consider the load capacity for tensile stress applied to. Now, all the parts are pressureless sintered silicon carbide sintered bodies, the ceramic hanging rods 12 and 13 have a circular cross section with a diameter of 15 mm, and the width a of the through hole 21 is 5 mm. Further, the thickness b of the engaging member 22 is smaller than the width a of the through hole 21, and is 4 mm. Three-point bending stress occurs in the engaging member 22, that is, concentrated tensile stress occurs at the contact point between the tip 23 and the through hole 21 and the contact point between the side 24 and the round hole 27, so this portion has a high connection strength. It is often the point of connection.
Therefore, it is preferable to increase the load capacity against this stress by increasing the distance c between the tip 23 and the side 24. Here, the distance c is set to 24 mm.
And so. Note that the dimensions of the link plate 26 can be determined without much restriction from other parts, so it does not become a key point in the overall strength.

When a tensile load is applied to the above connection part, the breakage occurs at the through hole 2 of the ceramic hanging rod 12 or 13.
Although it occurs in one part, the calculated strength is 1109Kg. In addition, when a tensile test was actually conducted, it was able to withstand a load of 1200 to 1500 kg.
Therefore, it was confirmed that sufficient hanging strength can be obtained even when applied to a hanging rod for a radiant panel or the like.

In addition, it is important for this type of connection structure to have good assembly workability on site, but as is clear from Figures 1 and 2, this connection structure of ceramic hanging rods is extremely difficult to assemble. It's easy. Therefore, when installing radiant panels, etc.,
Work within the heating furnace can also be done in a short time.

Furthermore, when this connection structure is applied to the hanging rods of the radiant panel, the radiant panel is subjected to wind pressure due to the heated gas flow and bending stress is applied to the ceramic hanging rods 12 and 13, as described above, but the link plate 26 swings, the connecting portion 14
Since the ceramic rods 12 and 13 are bent in a direction parallel to the heated gas flow, generation of excessive bending stress on the ceramic rods 12 and 13 can be avoided. In this case, when the shape of the round hole 27 of the link plate 26 is made circular, the connecting part 14 can be bent at the largest angle. Preferably, 27 is a long hole that is long in the axial direction of the link plate 26. Furthermore, during earthquakes and repair work, etc.
Although the ceramic hanging rods 12 and 13 may be subjected to stress in a direction perpendicular to the heated gas flow, in this connection structure, the ceramic hanging rods 1
By providing a certain amount of clearance between the links 2 and 13 and the link plate 26, the connecting portion 14 can be bent to some extent in the direction perpendicular to the heated gas flow.

10-12 illustrate a tubular link 28 for use in another embodiment of the invention. That is, in the embodiment shown in FIG. 1, a pair of plate-shaped link plates 26, 26 are used as link members, but a single tubular link member 28 may be used instead. Four long holes 29, 29, 30, 30 are formed in the tubular link material 28, one of the engaging members 22 is hooked into the long holes 29, 29, and the other is hooked into the long holes 30, 30. The engaging member 22 of is hooked. If the inner diameter of the tubular link member 28 is made larger than the outer diameter of the ceramic hanging rods 12, 13, and the elongated holes 29, 29, 30, 30 are made larger than the engaging member 22, flexible ceramic hanging can be achieved as well. A connected structure of rods can be realized.

In the above-mentioned embodiment, the ceramic hanging rods 12 and 13 have a circular cross section, but they may have a polygonal or other suitable cross section. Further, the shape of the engaging member 22 can be changed as appropriate depending on the required strength.

Furthermore, the round holes 27, 27 formed at both ends of the link plate 26 or the elongated holes 29, 30 of the tubular link material 28 may be integrated into one elongated hole.

"Effects of the Invention" As explained above, according to the connecting structure of ceramic hanging rods according to the present invention, the plate-shaped engaging members are inserted into the long through holes at the ends of the pair of ceramic hanging rods, respectively. Since the link members are hooked onto the protrusions provided on both sides of the engaging member, connection can be performed with a simple operation at the site. In addition, by making the engagement member plate-shaped,
It is possible to prevent the engaging member from becoming a strength point and to be able to sufficiently withstand large tensile loads. Furthermore, when the connected ceramic rods are subjected to a lateral force, they can be bent to some extent at the connecting portions, so that excessive bending stress can be avoided in the ceramic hanging rods. In addition, since the connecting structure and the structure of the component parts are relatively simple, manufacturing is easy and the cost can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a front cross-sectional view showing one embodiment of a connecting structure for ceramic hanging rods according to the present invention, Fig. 2 is a side cross-sectional view of the connecting structure, and Fig. 3 is a hanging radiant panel to which the connecting structure is applied. Front view showing the lowering structure,
Fig. 4 is a front view showing the end of the ceramic hanging rod used in the same connection structure, Fig. 5 is a side view of the end of the ceramic hanging rod, and Fig. 6 is used in the same connection structure. FIG. 7 is a front view of the engaging member, FIG. 7 is a side view of the engaging member, FIG. 8 is a front view of a link plate used in the connection structure, and FIG. 9 is a side view of the link plate. . FIG. 10 is a plan view showing a tubular link material used in another embodiment of the present invention, FIG. 11 is a side view of the same tubular link material, and FIG. 12 is a view taken along the line X-X in FIG. 10. FIG. In the figure, 12 and 13 are ceramic hanging rods, 1
4 is a connecting portion, 21 is a through hole, 22 is an engaging member, 26
is a link plate, 27 is a round hole, and 28 is a tubular link material.

Claims (1)

[Scope of Claims] 1. A pair of ceramic hanging rods to be connected, each having a long through hole formed in the axial direction of the rod at the end thereof, and a pair of plate-shaped engaging members inserted into each of the through holes; and a link member hooked to a protrusion provided on both sides of each of the engaging members, and the contact portion side of the engaging member with the through hole of the ceramic hanging rod is a plate-shaped wide surface side. A connecting structure of ceramic hanging rods characterized by being formed in a bulging arc shape when viewed from above. 2. In claim 1, a contact portion of the inner surface of the through-hole of the ceramic hanging rod with the engaging member is formed in a concave arc shape when viewed from the side where the through-hole opens, and the engaging member The cross section of the contact portion with the through hole and the contact portion with the link member taken in a direction perpendicular to the plane of the flat plate is formed in a bulging arc shape, and the through hole of the engagement member A connecting structure of ceramic hanging rods, wherein the radius of curvature of the bulging arc of the contact portion with the through hole is smaller than the radius of curvature of the concave arc of the through hole.