JPH05641Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a support structure for heat exchanger tubes arranged in a fluidized bed section of a fluidized bed boiler or the like.

BACKGROUND TECHNOLOGY As shown in FIG. 3, in a heat transfer tube arranged horizontally in a fluidized bed section of a fluidized bed boiler, one end of the heat transfer tube 2 is fixedly supported on a furnace wall 7, and the other end near a bend section 9 is fixedly supported. It was supported within the fluidized bed 1 by a wear-resistant material.

Furthermore, since the bend portion 9 is subject to more wear than other horizontal portions, a protector 19 made of a wear-resistant material is provided thereon.

Problems to be Solved by the Invention However, supporting the heat exchanger tubes in the fluidized bed is not only not supported reliably due to thermal expansion of the heat exchanger tubes themselves, but also because the support structure is abraded by the fluidized medium. Therefore, long-term support is difficult.

Furthermore, since the bend portion was provided with a protector made of a wear-resistant material, there were many economical disadvantages.

Means for Solving the Problems This invention has a structure that sufficiently absorbs expansion and contraction without installing the support on the thermal expansion side of the heat exchanger tube in a fluidized bed that is subject to severe wear, and also has a structure that sufficiently absorbs expansion and contraction in the bend portion. The above-mentioned problem was solved by installing it in a difficult-to-reach recess in the furnace wall.Specifically, the fluidizing system fluidizes the fluidized medium by ejecting fluidizing air from a fluidizing nozzle located at the bottom of the fluidized bed. In the heat exchanger tube arranged in the layer section, a support metal fitting is attached to the tip of the bend part of the heat exchanger tube, and the metal fitting is inserted into the support tube fixed to the casing to be supported in a flexible manner, and the other parts of the support tube are A heat exchanger tube having a cleaning air supply pipe attached to its end and disposed in a fluidized bed section with the bend section installed in a recessed section of a furnace wall.

Effect: The fluidized medium in the fluidized bed flows by the jet of fluidized air from the fluidized nozzle, and the fuel in the bed is combusted.

The high heat from this combustion is transferred to the heat transfer tubes and heats the fluid within the tubes.

On the thermal expansion side of the heat exchanger tube, one end of which is fixedly supported on the furnace wall, the tip of the bend portion is telescopically supported by the support tube via a support fitting, so the thermal expansion of the heat exchanger tube can be performed without restriction. be exposed.

Further, since a recess is formed in the furnace wall and the bend portion and supporting metal fittings are installed within the recess, the effect of the flow of the fluid medium on the bend portion and the supporting metal fittings is very small. Further, when the heat exchanger tube becomes dirty due to long-term use, the heat exchanger tube can be cleaned by sending cleaning air into the furnace through the support tube.

Embodiment An embodiment of this invention will be described with reference to FIGS. 1 and 2.

In the figure, 1 is a fluidized bed, 2 is a heat exchanger tube, 3 is a wind box, 4 is a fluidizing nozzle, and 5 is a fluidizing air supply pipe.

Air from the fluidizing air supply pipe 5 is ejected from a fluidizing nozzle 4 attached to the wind box 3, and the fluidized medium is brought into a fluidized state to form a fluidized bed 1.

A heat transfer tube 2 is installed in the fluidized bed 1, and the header 6 side of the heat transfer tube 2 is fixed to a casing 8 of a furnace wall 7.

The support of the heat exchanger tube 2 in the direction opposite to that of the heat exchanger tube 2 is achieved by inserting a support fitting 10 welded to the tip of the bend portion 9 of the heat exchanger tube into the support tube 13 fixed to the casing 12 of the furnace wall 11. This is done by

This support tube 13 is connected to the support hardware 10.
It is flexible and flexible.

The other end of this support tube 13 is closed by a tube sheet 14, and an air supply tube 15 for cleaning is attached to this tube sheet 14.
is normally closed by a plug 16.

Further, the inside of the support tube 13 is covered with a furnace wall 11 made of a refractory material to prevent the support tube 13 from being abraded by the fluidized medium and burned out by heat.

A recess 17 is formed in the furnace wall 11 at a location where the bend portion 9 and the supporting hardware 10 are installed, and the support tube 13 opens into the recess 17.

As described above, the heat transfer tube 2 undergoes thermal expansion due to heating by the fluidized medium in the fluidized bed 1, but this expansion is relieved by the support metal fittings 10 expanding and contracting within the support tube 13. Hardware 10 and support tube 13
The heat exchanger tube 2 is supported easily by this.

At this time, since the bend part 9 and the supporting hardware 10 are installed in the recess 17 formed in the furnace wall 11, the influence of the flow of the fluid medium on the bend part and the supporting hardware is very small. Further, when the heat exchanger tube becomes dirty due to long-term use, the heat exchanger tube can be cleaned by sending cleaning air into the furnace through the support tube.

Effects of the invention According to this invention, a support metal fitting is attached to the tip of the bend portion of the heat transfer tube, and the metal fitting is inserted into the support tube fixed to the casing to support the heat transfer tube in a flexible manner. This can be done reliably without being affected by expansion and contraction due to thermal expansion of the heat tube, and since the bend part is installed in a recess in the furnace wall,
The bend part and the supporting metal fittings do not wear out due to the flow of the fluid medium, and therefore the supporting metal fittings can be made of ordinary materials, which is inexpensive and requires less replacement. There is no need for a protector, making it economical. Furthermore, when the heat exchanger tube becomes dirty due to long-term use, the heat exchanger tube is cleaned by sending cleaning air into the furnace through the support tube, and a special independent device is used to clean the heat exchanger tube. You can easily do it without any hassle.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of an embodiment of this invention;
The figure shows a detailed view of the main part, and FIG. 3 shows an explanatory diagram of a conventional example. DESCRIPTION OF SYMBOLS 1... Fluidized bed, 2... Heat exchanger tube, 4... Fluid nozzle, 9... Bend part, 10... Support hardware, 11
... Furnace wall, 12 ... Casing, 13 ... Support pipe, 15 ... Air supply pipe, 17 ... Recess.

Claims (1)

[Scope of utility model registration request] In a heat transfer tube disposed in a fluidized bed section that fluidizes a fluidized medium by ejecting fluidizing air from a fluidization nozzle disposed at a lower portion of the fluidized bed, a supporting hardware is attached to the tip of a vent portion of the heat transfer tube, The metal fittings are inserted into a support tube fixed to the casing and supported so as to be expandable and retractable, an air supply tube for cleaning is attached to the other end of the support tube, and the vent part is arranged in a recess in the furnace wall. heat exchanger tubes placed in the fluidized bed section.