JPH0732309U - Sealing device for the boiler furnace wall penetration part of the heat exchanger tube - Google Patents

Abstract

(57) [Abstract] [Purpose] A plurality of heat exchanger tubes, a channel steel having a plurality of through holes through which the heat exchanger tubes are inserted at the bottom of the groove, each of the through holes and heat inserted through them. A boiler for a heat exchanger tube comprising a seal weld connecting the exchanger tube, a pair of side plates welded to both outer sides of the channel steel, and a crown plate welded to the outer side of each side plate. In the sealing device for the penetration portion of the furnace wall, generation of thermal stress / bending stress at the root portion of the seal welding portion is prevented so that an accident due to fatigue fracture or creep damage does not occur. A seal plate having a through hole through which the heat exchanger tube is inserted is fixed by welding both side edges to inner surfaces of the pair of side plates, and the heat exchanger tube, the side plate, and the seal plate. The space surrounded by and was filled with heat insulating material.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a seal device for a boiler furnace wall penetration portion of a heat exchanger tube.

[0002]

[Prior art]

 3 is a perspective view of a portion where the heat exchanger tube penetrates the boiler furnace wall, and FIG. 4 is a sectional view taken along line YY of FIG. In the figure, 1 is a furnace evaporation tube, 2 is a heat exchanger tube, 3 is channel steel, 4A to 4C are welded parts, 5 is a side plate, and 6 is a crown plate.

A heat exchanger tube 2 is penetratingly installed in a ceiling portion or a side wall portion of a boiler furnace wall constituted by the furnace evaporation tube 1. The heat exchanger pipe 2 is a superheater pipe or a reheater pipe, and these are connected by welding to a pipe header (not shown) provided outside the furnace wall. The penetration portion of the heat exchanger tube with respect to the furnace wall must have a seal structure so that combustion gas in the furnace does not leak. This seal structure is constructed such that the heat exchanger tube 2 is inserted into the same through hole of the channel steel 3 having a through hole having the same inner diameter as the outer diameter of the heat exchanger tube 2 at the groove bottom. Seal welding 4A over the circumference, side plate 5 is welded 4B to the side surface of the grooved steel 3 to hold the grooved steel 3 and sealed, and crown plate 6 is welded 4C to the side surface of the side plate 5. It has a sealed structure.

[0004]

[Problems to be solved by the device]

 In the above-mentioned structure in which the heat exchanger tube 2, the channel steel 3, the side plate 5, and the crown plate 6 are integrally connected by welding, the heat exchanger tube 2 is connected to the channel steel 3. The stress concentrates on the root portion 7 of the seal welded portion 4A in the penetrating portion. Therefore, the thermal stress due to the difference in thermal expansion between the inside and outside of the furnace when the boiler starts and stops, and the bending stress due to the runout of the heat exchanger tube during operation repeatedly act on the seal welding root 7, and Fatigue fracture occurs from the root part, and since this part is exposed to high temperature, creep damage also occurs, and in the worst case, fatigue fracture and creep damage overlap, leading to a steam leakage accident relatively early. There was a risk of rising.

The present invention solves the above-mentioned drawbacks of the prior art, and generates thermal stress and bending stress at the root portion of the seal weld connecting the through holes of the channel steel and the heat exchanger tubes inserted therein. To prevent accidents due to fatigue damage and creep damage.

[0006]

[Means for Solving the Problems]

 The present invention has solved the above-mentioned problems, and includes a plurality of heat exchanger tubes, a channel steel having a plurality of through holes through which the heat exchanger tubes are inserted in the groove bottom, the through holes and the through holes. Heat consisting of seal welds connecting the inserted heat exchanger tubes, a pair of side plates welded to both outsides of the channel steel, and a crown plate welded to the outsides of each side plate. In a sealing device for a boiler furnace wall penetration portion of an exchanger tube, a seal plate having a through hole through which the heat exchanger tube is inserted is fixed by welding both side edges to the inner surfaces of the pair of side plates. However, the present invention relates to a sealing device for a penetration portion of a boiler furnace wall of a heat exchanger pipe, characterized in that a space surrounded by the heat exchanger pipe, the side plate and the seal plate is filled with a heat insulating material.

[0007]

[Action]

 In the present invention, the seal plate is fixed between the inner surfaces of the side plates, and the inside of the seal plate is filled with the heat insulating material, so that the combustion gas does not flow into the inside of the side plate or the channel steel, so The temperature at the root of the seal weld between the exchanger tube and the channel steel is lower than that of the conventional structure, and the temperature difference between the outside of the furnace is small. Therefore, the thermal stress due to the difference in thermal expansion that occurs when the boiler starts and stops is reduced, and the bending stress due to runout of the heat exchanger tube that occurs at the above-mentioned seal welding route during operation is also transmitted through the seal plate. Since the side plate holds the heat exchanger tubes, it is significantly reduced, and fatigue damage and creep damage that may occur at the seal welding root can be prevented in advance. .

[0008]

【Example】

 1 is a vertical sectional view of a boiler furnace wall penetrating portion according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line XX of FIG. In the figure, 1 is a furnace evaporation tube, 2 is a heat exchanger tube, 3 is a channel steel, 4A to 4C are welded parts, 5 are side plates, 6 is a crown plate, 7 is a heat exchanger tube and channel steel. It is a seal welding route portion between and. The above configuration is the same as the conventional technique. Reference numeral 8 is a seal plate, and as shown in FIG. 2, has a through hole having the same outer diameter as the outer diameter of the heat exchanger tubes 2 for inserting the heat exchanger tubes 2. 4D is a welded portion for fixing both side portions of the seal plate 8 to the inside of the side plate 5. Reference numeral 9 is a heat insulating material filled in the space surrounded by the heat exchanger tube 2, the welded portion 4A, the channel steel 3, the side plate 5, the welded portion 4D, and the seal plate 8. The heat exchanger tube 2 is only inserted into the through hole of the seal plate 8 and they are not welded and fixed to each other. The heat insulating material is for reducing the temperature difference between the inside and outside of the furnace at the seal welding root portion 7.

In the boiler furnace wall penetrating portion having the above configuration, since the seal plate 8 is provided inside the side plate 5, combustion gas does not flow into the inside of the side plate 5 or the channel steel 3, The temperature of the seal welding root portion 7 between the heat exchanger tube 2 and the channel steel 3 becomes lower than that of the conventional structure, and the temperature difference between the inside and outside of the furnace at this portion becomes small. Further, by filling the inside of the side plate 5 provided with the seal plate 8 with the heat insulating material, the temperature difference between the inside and outside of the furnace in the root portion 7 is further reduced. Therefore, the thermal stress due to the difference in thermal expansion that occurs when the boiler starts and stops is reduced. Bending stress due to runout of the heat exchanger tube generated in the seal welding root portion 7 during operation is also significantly reduced because the heat exchanger tube is held by the side plate 5 via the seal plate 8. It As a result, the problems such as fatigue fracture and creep damage that occur in the seal welding root portion 7 are solved.

[0010]

[Effect of device]

 In the seal device for the boiler furnace wall penetration part of the heat exchanger tube of the present invention, a seal plate having a through hole through which the heat exchanger tube is inserted is welded at its both side edges to the inner surface of a pair of side plates. Since the space surrounded by the heat exchanger tubes, side plates and seal plates is filled with a heat insulating material, the through holes of the channel steel and the heat exchanger tubes inserted through them are fixed. It is possible to prevent the occurrence of thermal stress and bending stress at the root of the seal weld to be connected, and prevent accidents due to fatigue fracture and creep damage.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a boiler furnace wall penetrating portion according to an embodiment of the present invention.

2 is a sectional view taken along line XX of FIG.

FIG. 3 is a perspective view of a conventional boiler furnace wall penetrating portion.

FIG. 4 is a sectional view taken along line YY of FIG.

[Explanation of symbols]

 1 Furnace Evaporation Pipe 2 Heat Exchanger Pipe 3 Channel Steel 4A-4D Welding Part 5 Side Plate 6 Crown Plate 7 Seal Welding Root Part 8 Seal Plate 9 Heat Insulating Material

Claims (1)

[Scope of utility model registration request] 1. A plurality of heat exchanger tubes, a channel steel having a plurality of through holes through which the heat exchanger tubes are inserted at a groove bottom, each of the through holes and a heat exchanger tube inserted through them. Boiler furnace wall penetrating portion of heat exchanger tube consisting of seal welded portion connecting to each other, a pair of side plates welded to both outer side portions of the channel steel, and a crown plate welded to outer side portions of the respective side plates. In the sealing device, the seal plate having a through hole into which the heat exchanger tube is inserted is fixed by welding both side edges to the inner side surfaces of the pair of side plates, and the heat exchanger tube and the side plate. A seal device for a boiler furnace wall penetration portion of a heat exchanger tube, characterized in that a space surrounded by a seal plate is filled with a heat insulating material.