JPH05221740A - Joint structure of ceramic pipe - Google Patents

Abstract

PURPOSE:To provide a joining structure of ceramic pipe possible to attain high reliability in a high temp. atmosphere and easy to assembly free from high temp. oxidation of a joint part, defect by difference of thermal expansion, addition of a cooling device, crack generation at the time of operation or the like. CONSTITUTION:The cooling device is unnecessary and defect caused by oxidative corrosion or the difference of thermal expansion is prevented even at the high temp. atmosphere by using a ceramic joint 12 made of the same material as each of ceramic filters 11a, 11b, the upper side of the ceramic filter 11a is smoothly joined without slipping by providing a tapered part 15 and crack generation by stress concentration is prevented by providing a R worked part 14. Furthermore, filling work of an inorganic adhesive 13 is easily executed by providing a gradient worked part 12b and since the adhesive 13 is formed by mixing the same ceramic, difference of thermal expansion is small and joining strength is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic pipe joining structure applied to a filter of a dust remover for a pressurized fluidized bed boiler, a high temperature gas filter and the like.

[0002]

2. Description of the Related Art Conventionally, as a technique for lengthening a ceramic tube in a high-temperature gas filter, a heat-resistant metal is used for the joint portion to lengthen the length of the joint.

However, with respect to a gas having a higher temperature of, for example, 800 ° C. or higher, there arises a problem of high temperature oxidation of the metal joint portion or deterioration of adhesiveness due to a difference in thermal expansion between the metal joint portion and the ceramic tube, and the above heat resistance. It was difficult to apply a flexible metal joint. Further, even when a joint part made of the same material as the ceramic tube is used, there is a problem that cracks in the toe part occur at stress concentration points during operation.

[0004]

Therefore, when the conventional joint portion is used, the joint airtightness is improved along with problems such as high temperature oxidation, loss due to a difference in thermal expansion, addition of a cooling device, and cracking during operation. Therefore, there is a problem that workability at the assembly stage is poor.

The present invention has been made in view of the above problems,
Easily assembled ceramic tubes that can achieve high reliability even in high temperature atmosphere without problems such as high temperature oxidation of joints, loss due to thermal expansion difference, addition of cooling device, cracking during operation, etc. It is intended to provide a structure.

[0006]

That is, the joining structure of a ceramic tube according to the present invention is a joint formed by using the same kind of material as that of the ceramic tube to be joined, and an upper side of this joint and one of the ceramics to be joined. The outer periphery of the upper end joint of the ceramic pipe to be joined at the joint between the lower part of the joint and the other ceramic pipe to be joined The R-processed portion formed on the outer peripheral edge of the joint on the joint side corresponding to the corner portion, and the inner surface of the joint cylindrical portion extended from the R-processed portion along the outer peripheral surface of the other ceramic tube to be joined. Filled in the gap between the inclined processed portion formed so that the inner diameter of the joint cylindrical portion gradually increases in the downward direction, and the inclined processed portion on the inner side surface of the joint cylindrical portion and the outer peripheral surface of the other ceramic tube to be joined. Was
It comprises a ceramic tube to be joined and an adhesive produced by mixing the same kind of material.

[0007]

In other words, the joint made of the same material as that of the ceramic pipe to be joined prevents damage due to high temperature oxidation and thermal expansion difference, and the provision of the tapered portion allows one ceramic pipe to be joined smoothly without displacement. Bonding and the provision of the R-processed portion prevent the occurrence of cracks due to stress concentration.

Further, by providing the above-mentioned inclined processing portion, the filling operation of the adhesive can be easily performed, and the adhesive is produced by mixing the same kind of material as the ceramic tube to be joined, so that the difference in thermal expansion is reduced. Bonding strength is improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a joint structure of a ceramic tube, in which an upper ceramic filter 11a and a lower ceramic filter 11b are joined via a ceramic joint 12.

The ceramic filters 11a and 11b are cordierite (electro-melting material) having a particle diameter of 150 to 300 μm.
Ceramic joint made from
Is made of cordierite of the same kind as the ceramic filters 11a and 11b and having a particle diameter of 10 μm as a raw material. The ceramic filters 11a and 11b
Inorganic adhesive 1 required for joining b to the ceramic joint 12
For 3, an adhesive containing 25% of cordierite ceramic powder having a particle diameter of 10 μm added and mixed is used.

In this case, the ceramic filter 11
a, 11b, ceramic joint 12, and inorganic adhesive 13
By using the same type of ceramic material for both of them, oxidative corrosion in a high temperature atmosphere and damage due to a difference in thermal expansion are prevented, and the mutual bonding strength is enhanced.

A tapered portion 15 having a gradually decreasing diameter in the vertical direction is formed between the joints between the ceramic joint 12 and the upper ceramic filter 11a, whereby the upper ceramic filter 11a is The ceramic joint 12 is smoothly joined without being displaced by its own weight. FIG. 2 is an enlarged partial cross-sectional view showing a joint portion between the ceramic joint 12 and the lower ceramic filter 11b in the above-mentioned ceramic pipe joint structure.

A rounded portion 14 is formed on the outer peripheral edge of the lower portion of the ceramic joint 12 with the ceramic filter 11b corresponding to the outer peripheral corner portion of the upper end joint of the ceramic filter 11b. As a result, the stress concentration generated in the corresponding joint during operation is relieved, and the occurrence of cracks is prevented.

On the inner side surface of the joint cylindrical portion 12a extending from the R-processed portion 14 of the ceramic joint 12 along the outer peripheral surface of the ceramic filter 11b below, the inner diameter of the joint cylindrical portion 12a is downward. A sloped portion 12b having a gradually increasing diameter is formed. The sloped portion 12b is formed.
The inorganic adhesive 13 is injected and filled into the gap between the lower ceramic filter 11b and the lower ceramic filter 11b. in this case,
By providing a gap corresponding to the inclined processed portion 12b, the workability of injecting the inorganic adhesive 13 is improved.

Therefore, according to the ceramic tube joining structure having the above-mentioned structure, the ceramic filters 11a and 11b are joined together.
The ceramic joint 12 made of the same material as
Even in a high temperature environment of 0 ° C., a cooling device is not required, the size is small and the efficiency is high, and damage due to oxidative corrosion and thermal expansion difference can be prevented, and by providing the tapered portion 15, the upper ceramic filter 11a can be smoothly joined without displacement Further, by providing the R processed portion 14, it is possible to prevent cracking due to stress concentration.

Further, by providing the inclined processed portion 12b, the filling work of the inorganic adhesive 13 can be easily performed, and the adhesive 13 is also produced by mixing the same kind of ceramic material to reduce the difference in thermal expansion. The bonding strength can be improved.

[0018]

As described above, according to the present invention, a joint formed of the same material as that of the ceramic tube to be joined and the joint portion between the upper side of the joint and one of the ceramic tubes to be joined are mutually connected. At the joint between the formed taper portion that gradually decreases in the vertical direction and the lower side of the joint and the other ceramic pipe to be joined, the joint corresponding to the outer peripheral corner of the upper end joint of the ceramic pipe to be joined side R-shaped portion formed on the outer peripheral edge of the joint portion on one side, and the joint cylindrical portion formed on the inner side surface of the joint cylindrical portion extending from the R-treated portion along the outer peripheral surface of the other ceramic tube to be joined. The inclined processed portion whose inner diameter gradually increases in the downward direction, and the gap between the inclined processed portion on the inner side surface of the joint cylindrical portion and the outer peripheral surface of the other ceramic tube to be joined is filled with the ceramic tube to be joined. A connection created by mixing similar materials. Since it is provided with an agent, it is possible to obtain high reliability even in a high temperature atmosphere without problems such as high temperature oxidation of the joint, loss due to thermal expansion difference, addition of cooling device, cracking during operation, etc. It is possible to provide a joined structure of a ceramic tube which is easy to assemble.

[Brief description of drawings]

FIG. 1 is a sectional configuration view showing a joint structure of a ceramic tube according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing, in an enlarged manner, a joint between a ceramic joint and a lower ceramic filter in the ceramic pipe joint structure.

[Explanation of symbols]

11a, 11b ... Ceramic filter, 12 ... Ceramic joint, 12a ... Joint cylindrical portion, 12b ... Inclined portion, 1
3 ... Inorganic adhesive, 14 ... R processed part, 15 ... Tapered processed part.

Claims (1)

[Claims] 1. A joint made of the same material as that of the ceramic tube to be joined, and a joint between the upper side of the joint and one of the ceramic tubes to be joined are formed so that the diameter gradually decreases in the vertical direction. At the joint between the tapered portion and the lower side of the joint and the other ceramic tube to be joined, it is formed on the outer peripheral edge of the joint on the joint side corresponding to the outer peripheral corner of the upper end joint of the ceramic tube to be joined. An R processed portion and an inner side surface of a joint cylindrical portion extended from the R processed portion along the outer peripheral surface of the other ceramic tube to be joined,
A slanting portion in which the inner diameter of the joint cylindrical portion gradually increases in the downward direction, and a gap between the slanting portion on the inner side surface of the joint cylindrical portion and the outer peripheral surface of the other ceramic tube to be joined is filled, A bonding structure for a ceramic tube, comprising: a bonding ceramic tube; and an adhesive produced by mixing the same kind of material.