JPH10185071A - Expansion bellow mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the bellows of the expansion bellows from being sharply bent due to a change in the internal pressure of the duct, thereby preventing the expansion bellows from being damaged. SOLUTION: A fixed side flange 8 provided on a duct 3 and a mounting flange 9 provided on an expansion bellow 6 are opposed to each other with a gasket 10 interposed therebetween, and a support plate 11 is arranged on a side of the mounting flange 9 opposite the gasket 10; In an expansion bellows mounting structure in which the fixed side flange 8, the gasket 10, the mounting flange 9, and the support plate 11 are fastened and fixed by the fastening bolts 12, one end 14a is formed between the mounting flange 9 and the support plate 11. The other end 14b is extended by a required length L along the outer surface of the straight portion 7b of the expansion bellows 6 and the wire 1
5 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an expansion bellows mounting structure.

[0002]

2. Description of the Related Art An expansion bellows is provided in a duct for introducing a gas whose temperature fluctuates such as boiler exhaust gas.

FIG. 3 shows an example of a system for desulfurizing exhaust gas from a boiler. Exhaust gas 2 after exhaust heat recovery by a heat exchanger 1 (for example, an air heater or the like) is passed through a duct 3.
Is supplied to the absorption tower 4 of the flue gas desulfurization unit through the
2 shows a duct device 5 for guiding the exhaust gas 2 after desulfurization through a duct 3 to a downstream device.

[0004] In such a duct device 5, each duct 3 expands and contracts due to a change in temperature of the exhaust gas 2, so that an excessive force acts on the heat exchanger 1, the absorption tower 4, the duct 3, and the like. The duct 3 is provided with an expansion bellows 6 for absorbing deformation of the duct 3 in order to prevent the deformation.

As shown in FIGS. 4 and 5, the expansion bellows 6 has a bellows portion 7 for allowing deformation.
a, straight ends 7b are formed at both ends, and an end of the straight part 7b is provided with a mounting flange formed so as to coincide with a fixed side flange 8 formed at an end of the duct 3 which is a fixed side. The mounting flange 9 is disposed so as to face the fixed side flange 8 with the gasket 10 interposed therebetween.

Further, the gasket 1 of the mounting flange 9 is provided.
0, a support plate 11 is arranged on the opposite side, and the fixed side flange 8, gasket 10, mounting flange 9, and support plate 1 are provided.
1 are fixed together by fastening bolts 12 so that the duct 3 is allowed to expand and contract by deformation of the bellows portion 7a of the expansion bellows 6. Reference numeral 13 in FIG. 4 denotes a fixing hardware for fixing and supporting the duct 3.

The expansion bellows 6 provided in the duct device 5 (FIG. 3) for guiding the exhaust gas 2 and the like of the boiler as described above is generally made of a nonmetallic material obtained by combining a rubberized tetron cloth and a glass cloth. It is formed.

[0008]

In the duct device 5 as shown in FIG. 3, the pressure of the exhaust gas 2 in the duct 3 greatly changes due to the start / stop of the boiler, the fluctuation of the load, and the like. As a result, the expansion bellows 6 expands as shown by phantom lines in FIGS.
Further, the corner portion A between the straight portion 7b of the expansion bellows 6 and the mounting flange 9 is sharply bent, and the daily start and stop operation (DSS) required in recent boilers in particular is performed. By
The corner portions A of the expansion bellows 6 are repeatedly bent so that the corners A are damaged by mechanical fatigue, and the straight portions 7b of the expansion bellows 6
In such a case, there is a problem that the contact is damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and it is intended to prevent the bellows of the expansion bellows from being sharply bent due to a change in the internal pressure of the duct, thereby preventing the expansion bellows from being damaged. It is an object of the present invention to provide an expansion bellow mounting structure.

[0010]

According to the present invention, a fixed side flange provided on a duct and a mounting flange provided on an expansion bellow are opposed to each other with a gasket interposed therebetween, and a support plate is disposed on a side of the mounting flange opposite to the gasket. In the expansion bellows mounting structure, the fixed side flange, the gasket, the mounting flange, and the support plate are fastened and fixed by fastening bolts, one end is held between the mounting flange and the support plate. An expansion bellows mounting structure, characterized in that the other end is provided with a cored gasket extending a required length along the outer surface of the straight portion of the expansion bellows and having a wire material provided at the end thereof. .

In the present invention, since the outer peripheral surface of the expansion bellows near the mounting flange is pressed by the cored gasket, the corner portion between the expansion bellow and the mounting flange may be sharply bent due to fluctuations in the internal pressure of the duct. It disappears and becomes gently deformed, and the corners are prevented from fattering due to sharp bends, so that corners are prevented from being damaged by fatigue, and the straight portions of the expansion bellows are deformed to support plates. Also, the occurrence of a problem such as damage due to contact with the like can be prevented.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an embodiment of the present invention. Similar to FIG. 5, a fixed flange 8 provided on a duct 3, a gasket 10, and an expansion bellows 6 are provided.
In the expansion bellows mounting structure in which the mounting flange 9 and the support plate 11 are fastened and fixed by the fastening bolts 12, the one end 14a has a flange shape and the mounting flange 9 and the support plate 11 are connected to each other. The other end 14b is extended along the outer surface of the linear portion 7b of the expansion bellows 6 by a required length L so as to surround the entire circumference of the linear portion 7b. A cored gasket 14 having a configuration in which a wire 15 is inserted into a portion is provided.

The cored gasket 14 is made of a heat-resistant material such as a normal gasket or glass cloth, and the wire 15 made of a metal wire or carbon fiber provided at the tip of the other end 14b is It is provided so that the straight part 7b of the expansion bellows 6 may be fastened from the outer periphery.

FIG. 2 shows another example of the cored gasket 14, and in FIG.
The wire 15 is buried at the end of the wire b. In FIG. 2, the plate-like gasket is folded back at the other end 14b so as to wrap the wire 15, thereby forming a double structure.
The cored gasket 14 is provided with a wire 15 at the tip of the other end 14b.

The operation of the embodiment shown in each of the above figures will be described below.

As described above, one end 14a is sandwiched between the mounting flange 9 and the support plate 11, and the other end 14b is extended along the outer surface of the linear portion 7b of the expansion bellows 6, and further extended therefrom. When the cored gasket 14 having the configuration in which the wire 15 is inserted at the distal end thereof is provided, the pressure in the duct 3 increases, and as shown by a virtual line in FIG.
Even if the expansion bellows 6 is deformed to expand,
Since the outer periphery of the linear portion 7b of the expansion bellows 6 is pressed by the cored gasket 14, the corner portion A between the linear portion 7b of the expansion bellows 6 and the mounting flange 9 is not sharply bent, and is gentle. As a result, the corner portion A is prevented from being damaged due to fatigue, and the straight portion 7b of the expansion bellows 6 is supported by deformation. It is possible to prevent the occurrence of a problem such as damage due to contact with the plate 11 or the like.

The present invention can of course be applied to expansion bellows provided in various ducts other than the duct device shown in FIG.

[0019]

According to the present invention, since the outer peripheral surface near the mounting flange of the expansion bellows is pressed by the cored gasket, the corner portion between the expansion bellow and the mounting flange sharply changes due to the fluctuation of the internal pressure of the duct. It will not be bent, it will be deformed gently, and the corner portion will be prevented from fattering due to sharp bend, so that the corner portion will not be damaged by fatigue and the straight portion of the expansion bellows will be It is possible to obtain an excellent effect that it is possible to prevent the problem that the support plate or the like is damaged by the deformation due to the deformation.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment of the present invention.

FIG. 3 is a perspective view showing an example of a duct device provided in the desulfurization device of the boiler.

FIG. 4 is a cutaway front view showing an example of the expansion bellows provided in FIG. 3;

FIG. 5 is a sectional view taken along the line VV in FIG. 4 showing an example of a conventional expansion bellow mounting structure.

[Explanation of symbols]

 Reference Signs List 3 Duct 7b Straight portion 8 Fixed flange 9 Mounting flange 10 Gasket 11 Support plate 12 Fastening bolt 14 Cored gasket 14a One end 14b Other end 15 Wire L Required length

Claims (1)

[Claims] 1. A fixed side flange provided on a duct and a mounting flange provided on an expansion bellow are opposed to each other with a gasket interposed therebetween, and a support plate is disposed on a side of the mounting flange opposite to the gasket. In an expansion bellows mounting structure in which a gasket, a mounting flange, and a support plate are tightened and fixed by fastening bolts, one end is sandwiched between the mounting flange and the support plate, and the other end is a straight line of the expansion bellows. An expansion bellows mounting structure, comprising a cored gasket extending a required length along the outer surface of the portion and having a wire material provided at a distal end thereof.