JPS6037368B2 - heat shielding device - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a heat shielding device, and in particular, to a heat shielding device for reducing reflected heat from flames of burners, combustion gas, etc. in boilers, reforming furnaces, and various other heating furnaces. The present invention relates to a heat shielding device suitable for shielding.

[Background of the Invention] In boilers, waste furnaces, and various other heating furnaces used in chemical plants, factories, etc., the header or header of the heat exchanger tube and the curved portion of the heat exchanger tube or pend, etc. Components such as headers are heated by radiation heat from flames and combustion gases, causing thermal expansion, making it impossible to avoid the occurrence of thermal stress due to thermal expansion, which can deform or damage parts. Something happened.

Therefore, various heat shielding devices have been manufactured to shield the radiation heat from the burner flame, combustion gas, and the like. FIGS. 4 to 6 are cross-sectional views showing the arrangement of heat exchanger tubes, headers, bends, etc. in the furnace.

4 to 6, burners 3 are installed on the furnace wall 2 of the furnace 1.
is provided, and heat exchanger tubes 4 are disposed within the furnace 1.

Further, the header 5 and the pend 6 are housed in a header box 7 and a pend box 8, respectively. When the fuel is combusted by the burner 3, the temperature inside the furnace 1 is usually 1000 to 1
The temperature reached a high temperature of 300q0, and the flame of burner 3, furnace wall 2,
The header 5 and pend 6 are heated by radiation heat from the combustion gas and the like, and their temperature increases.

Therefore, the header 5 and the pend 6 are subjected to thermal stress due to the hot side effect, so that the header 5 and the pend 6 may be deformed or damaged. In order to prevent deformation and damage to the header 5 and pend 6 due to the generation of such thermal stress, various types of heat shielding devices have been manufactured in the past.

7 to 9 are diagrams showing a heat shielding pupil of a conventional header, in which FIGS. 7 and 8 are sectional views, and FIG. 9 is a plan view.

7 to 9, the header 5 of the heat exchanger tube 4 in the furnace 1 is housed in a header box 7. As shown in FIG.

A heat shielding plate 9 made of steel plate or rusted steel is provided to partition the furnace 1 and the header box 7. Furthermore, the heat shielding plate 9 is lined with a heat insulating material 10 such as brick,
The heat shielding effect is increased. In addition, in order to prevent the heat transfer tubes 4 from elongating and moving or the heat shield plate 9 to extend due to thermal expansion and to prevent contact between the heat transfer tubes 4 and the heat shield plate 9, the outer diameter of the heat transfer tubes 4 is A circular hole with a large diameter is provided in the heat shield plate 9.

Therefore, the mechanical strength of the heat shield plate 9 is weakened, and since both ends of the heat shield plate 9 are supported by the furnace wall 2, the central portion of the heat shield plate 9, that is, the vicinity of the heat exchanger tubes 4 is bent. In addition, the deflection increases as a result of receiving radiation heat from the flame and combustion gas of the burner 3, and both ends of the heat shield plate 9 supported by the furnace wall 2 come off the furnace wall 2, causing the heat shield function to deteriorate. Sometimes the results are not fulfilled. Furthermore, the heat shielding plate 9 that has come off the furnace wall 2 may damage the heat exchanger tubes 4, the header 5, etc., which has been a problem in the past. [Purpose of the Invention] The present invention was made to solve the above-mentioned problem, and is designed to shield the key radiation heat from the flame of the furnace burner and the combustion gas, so that the header and the pendant can be protected from thermal stress caused by thermal expansion. It is an object of the present invention to provide a heat shielding device that can be prevented from being deformed or damaged by.

[Summary of the invention]

This invention involves wrapping a flexible heat insulating material such as asbestos near the thermal stress generating part of the heat transfer tube, and using the aggregate of the flexible heat insulating material to thermally shield the thermal stress generating part. This is a characteristic feature.

[Embodiments of the Invention] Examples of the present invention will be described based on the drawings.

1 to 3 are views showing a heat shielding device of the present invention, in which FIG. 1 is a sectional view, FIG. 2 is a perspective view, and FIG. 3 is a plan view. 1 to 3, the headers 5 of the heat exchanger tubes 4 are housed in the header box 7, and the headers 5 of the heat exchanger tubes 4 are housed in the header box 7 at the entrance position of the header box 7, that is, near the thermal stress generation area. That is, a flexible heat insulating material 11 such as asbestos is wrapped around the head 5.

Then, a flexible heat insulating material 1 is wrapped around each heat exchanger tube 4.
1 and the outer surface of the flexible heat insulating material 11 wrapped around the adjacent heat transfer tube 4 are brought into contact with each other to form an aggregate of the flexible heat insulating material 11, and each heat transfer tube 4 is A slight gap 14 is provided between the wrapped flexible heat insulating material 11 and the furnace wall 2 to prevent the flexible heat insulating material 11 and the furnace wall 2 from coming into contact with each other. In addition, the flexible heat insulating material 11 wrapped around the heat transfer tube 4 is tied tightly using a heat insulating rope or a heat-resistant metal wire 12, and the heat transfer tube directly below the wrapped flexible heat insulating material 11 is tied tightly. Stud 1 on the outside of 4
A condensable heat insulating material 1 which is welded to 3 and wrapped around a heat exchanger tube 4.
1 to prevent it from falling off.

[Effects of the Invention] As explained above, the present invention provides flexible heat insulating material that is wound around the entrance position of the header box of each heat exchanger tube, that is, near the header, and wrapped around the adjacent heat exchanger tube. The outer surfaces of the flexible insulation materials are brought into contact with each other to form a thermal shielding device by the assembly of flexible insulation materials.

Therefore, the heat radiated from the burner flame and combustion gas to the header stored in the header box is shielded, so that the header does not become deformed due to thermal stress caused by thermal expansion, or This has the effect of preventing damage. In addition, since the heat transfer tube is wrapped with fugitive heat insulating material, even if there is a difference in expansion of the heat transfer tube, the heat transfer tube and the fugitive heat insulating material move together and provide heat shielding. There is an effect that can be done. Furthermore, since the conventional metal heat shield plate is not used, the heat shield plate may bend due to radiation heat and come off the furnace wall, resulting in loss of heat shield function or damage to the heat exchanger tubes and header. There is no effect.

[Brief explanation of the drawing]

1 to 3 are diagrams showing a heat shielding device of the present invention, in which FIG. 1 is a sectional view, FIG. 2 is a perspective view, FIG. 3 is a plan view, and FIGS. 4 to 6 are views. 7 to 9 are cross-sectional views showing the arrangement of heat transfer tubes, headers, bends, etc. in the furnace, and FIGS. 7 to 9 are views showing conventional header heat shielding devices, The sectional view and FIG. 9 are plan views. 1... Furnace, 2... Furnace wall, 3...
... Burner, 4 ... Heat exchanger tube, 5 ... Header, 6 ... Bend, 7 ... Header box, 8 ...・Bend box, 9...Heat shielding plate,
10, 11...Insulating material, 12...Insulating rope or heat-resistant metal wire, 13...Stud, 14...Gap. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] 1. A furnace including a furnace, a heat exchanger tube disposed in the furnace, and a thermal stress generating part such as a header or bend connected to the heat exchanger tube and stored in a storage section such as a header box or bend box. In various types of heating furnaces, a flexible heat insulating material is wrapped around the thermal stress generating part of the heat transfer tube, and the thermal stress generating part is heated by the aggregate of the wrapped flexible heat insulating material. A heat shielding device characterized by being shielded.