JPH0356724Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a device for preventing vibration of a group of heat exchanger tubes.

BACKGROUND OF THE INVENTION In order to prevent vibrations occurring in a group of tubes in a high-temperature gas atmosphere such as a boiler, a vibration prevention device having a partition plate structure as shown in FIG. 1 has conventionally been used. In FIG. 1, a partition wall is provided in a part of the vertical tube group 1 in order to prevent turbulent flow of combustion gas generated in the vertical tube group 1 and to change the natural frequency of this part.

This transmits the load of the anti-vibration buffs 2 to the horizontal pipe group 3 by stacking the anti-vibration buffs 2 on top of the supporting hardware 4 placed on the horizontal pipe group 3 and welding each layer. In addition, in order to prevent the anti-vibration bumps 2 from falling off due to the wind pressure and vibrations of combustion gas, each anti-vibration bump is slidably fixed to the vertical pipe group 1 using U-bolts 5, nuts 6, washers 7, etc. belongs to. 8
indicates the flow direction of combustion gas. Further, 9 is a reinforcing plate.

This conventional vibration prevention device had the following drawbacks.

(b) If there is a difference in elongation due to thermal expansion due to the difference in temperature or material between the vertical tube group 1 and the anti-vibration buffle 2, the distance from the support metal fitting 2 to the anti-vibration buffle 2 at the tip is large. Therefore, the difference in elongation also increases. At this time, if the sliding support function of the U-bolts 5 is obstructed by combustion scale fixed on the surface of the vertical tube group 1, it becomes impossible to absorb the difference in elongation, and one of the vibration prevention bolts 2 and the vertical tube group 1 becomes unable to absorb the difference in elongation. Or both become deformed or damaged.

(b) Since the load of the anti-vibration buttress 2 is intensively supported at the top or bottom, the load acting on the support parts (support metal fittings 4, horizontal pipe 3, etc.) is large, and a strength commensurate with this is required.

(c) For the same reason as (b), the actuation force required to cause slippage between the anti-vibration baffle 2 and the vertical tube group 1 becomes even greater, and deformation is likely to occur.

(d) The vibrating baffle 2 that has been deformed due to reasons (a) to (c) is separated from the vertical tube group 1, and is exposed to combustion gas, with a high risk of burning out.

(e) Support hardware (U-bolts 5, 6, 7 and support hardware 4 are not of a cooling type, so they are prone to burnout and there is a risk that the vibration prevention baffle 2 will fall off.

The present invention has been made for the purpose of eliminating the above-mentioned conventional drawbacks.

The present invention makes it easier to divide and absorb the absolute amount of thermal expansion difference that occurs between the vibration prevention buttfuls and the vertical tube group by increasing the number of support points, and the It is characterized by having a structure that makes it difficult for combustion gas to pass through gaps to absorb differences in thermal expansion.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 2 to 6.

FIG. 2 shows a state in which the vibration prevention device according to the present invention is installed in a group of heat exchanger tubes. Also the third
The figure is an enlarged view of section A in FIG. 2, and FIG. 4 is a view taken along line B--B in FIG. 3.

As shown in these figures, the present invention:
An inverted L-shaped support lug 1 is attached to the vertical tube group 1.
1 is welded to the support lug 11, and a vibration prevention buffle 12 is engaged with the support lug 11. Anti-vibration Batsuful 1
A reinforcing plate 13 is stacked and coupled to 2, and a long hole 14 is formed passing through the vibration prevention buffle 12 and the reinforcing plate 13, and the support lug 11 is engaged with this long hole 14. Furthermore, the vertical tube group 1 and the anti-vibration buffle 12 are auxiliary fixed using U-bolts 5 and nuts 6 similar to the conventional ones.

By the way, there are two types of anti-vibration buffs 12, a letter-shaped one 12a and a square-shaped one 12b, and these are usually used as a set. In other words, a set is made up of a square-shaped buttful 12b placed on a letter-shaped buttful 12a, and the joints between the two are welded. Therefore, when stacking the cross-shaped cross-fulls 12, the cross-shaped cross-fulls 12b of one group are stacked with the cross-shaped cross-fulls 12a of another group. The buffles 12a are made to overlap each other, and the sets of buffles 12 are suspended from the support lug 11 with a gap 15 so as to absorb the difference in thermal expansion.

The present invention is constructed as described above, and the load of the anti-vibration buffle 12 is transmitted to the vertical tube group 1 through the support lug 11 together with the reinforcing plate 13.
Further, the force that the anti-vibration baffle 12 receives due to wind pressure of combustion gas, vibration, etc. is supported by the vertical tube group 1 by the support lug 11, the U-bolt 5, and the like. The support lug 11 serves as a base point for thermal expansion, and the difference in thermal expansion between the anti-vibration buffles 12 and the vertical tube group 1 is absorbed by the gap 15 provided between the anti-vibration buffles 12.

As described above, according to the present invention, the following various effects can be obtained.

(b) By supporting the vibration prevention double 12 in parts and providing a gap 15 between them, the difference in thermal expansion with the vertical tube group 1 is reduced, the slide support function at the U bolt part 5 is easily activated, and vibration is prevented. Deformation, damage, and burnout of the prevention baffle 12, vertical tube group 1, and U-bolt portion 5 can be prevented.

(b) By overlapping the vibration prevention buffles 12 in the gaps 15, combustion gas can be prevented from easily passing through while maintaining the function of absorbing elongation.

(c) By welding and attaching the support lug 11 to the vertical tube group 1, the vibration prevention buffle 12 can be prevented from falling off because it is cooled by the tubes and will not burn out.

From the above, it is possible to extend the life of the vibration isolator, reduce the cost of replacement, and prevent deformation and damage of the vibration isolator and support (vertical pipe group 1), improving plant reliability. I can contribute.

The present invention is not limited to the above-mentioned embodiments, but
Various modifications can be made without departing from the spirit of the invention.

For example, as shown in FIG. 5, instead of the inverted L-shaped support lug 11, a straight bolt 16 is welded to the vertical pipe 1, and this bolt 16 is passed through the buttful 12 and fastened with a nut 18 through a washer 17. You may also wear them. Alternatively, as shown in FIG. 6, a vibration-preventing buffle 19 in the form of a flat plate may be used and attached to the vertical tube group 1 with their ends overlapping each other. Even in this case, since the buffle elongation reference point is determined for each buffle 19, the sliding amount due to thermal elongation is reduced.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a conventional vibration prevention device provided in a heat transfer tube group, FIG. 2 is a perspective view showing an embodiment of the vibration prevention device according to the present invention provided in a heat transfer tube group, and FIG. The figure is an enlarged view of part A in figure 2, and figure 4 is an enlarged view of part 3.
5 shows another embodiment of the present invention, a is a front view, b is a view taken along C-C line in figure a, and FIG. 6 is another embodiment of the present invention. It is a perspective view showing an example. 1... Vertical tube group, 11... Support lug, 12...
Vibration prevention Batsuful, 15... gap.

Claims (1)

[Scope of utility model registration request] In a device that prevents vibration of the heat exchanger tube group by attaching a vibration prevention buttful to some of the heat exchanger tubes in the heat exchanger tube group, the vibration prevention buttful is divided into a plurality of pieces in the longitudinal direction of the heat exchanger tubes, and the divided vibration prevention While arranging the buttfuls so that their edges overlap,
A vibration prevention device characterized in that a support lug fixed to a heat transfer tube is fitted into a hole provided in a desired divided vibration prevention buttful to serve as a base point for thermal expansion.