JPS60134147A - Water tube type boilder - Google Patents

Abstract

PURPOSE:To enhance the safety of a water tube type boiler by preventing the thermal deterioration of a combustion chamber and burners as well as raising the heat efficiency of the inner surface as a heating face of the combustion chamber by a method in which the combustion chamber is made up of a lower annular header and a water-cooled wall in which a heat shield plate is bonded to the inner surface of the water tubes. CONSTITUTION:An aperture is provided between upper and lower annular tube gangs in a water tube 3, and a combustion chamber 5 is formed of a water-cooled wall connected with a heat shield plate 13 of a concentricity with the upper and lower annular header and the lower annular tube gang 2. A combustion gas path is formed of a baffle body 9 and an outer wall. A burber 6 is connected to the water-cooled wall and the water tube 3 and positioned from the aperture of the water tubes into the combustion chamber 5. Since the inner surface of the combustion chamber 5 can be utilized as a heating surface, the ambient temperature of the combustion chamber 5 can be lowly controlled because thermal efficiency can be raised and also because the chamber 5 is formed of the lower annular header 2 and the water-cooled wall. Furthermore, since the burner 6 is connected to the wall-cooled wall and the water tube 3 and positioned into the chamber 5, the burner 6 can be cooled with water and thermal deterioration of the burner 6 can be prevented. Since blow-out of flame to the outside of the chamber 5 is prevented by the water-cooled wall, the safety of the boiler can be enhanced.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention improves thermal efficiency, protects the bar, and improves safety by effectively utilizing the combustion chamber of a domestic water heater equipped with a multi-tubular once-through heat exchanger. Regarding water tube boilers.

Structure of the conventional example and its problems Conventionally, a water tube boiler equipped with this type of multi-tubular once-through heat exchanger and using a horizontally cut burner is shown in Fig. 1 (al,
As shown in (b), a ring-shaped stop ring header 1 and a lower annular header 2 were connected by a large number of water pipes 3 standing upright in a ring shape. Insulating material 4 below the lower annular header 2
A combustion chamber 5, which was formed by

Further, the heat insulating material 4 was tightly wound around the upper and lower annular headers 1.2 and the chimney cap 7 attached to the upper end of the stop ring header 1. Further, a combustion gas passage 8 is formed by wrapping a heat insulating material 4 with a suitable gap on the outside of the water pipe 3 arranged in a ring shape, and a baffle body 9 is provided inside the water pipe as a baffle plate for the combustion gas. Ta.

The high-temperature combustion gas 10 generated by the burner 6 passes from the combustion chamber 5 to the inside of the lower annular header 2 as shown by arrow B.
After colliding with the baffle body 9, the gap created by the water pipe 3 and the heat insulating material 4 (combustion gas path 8), the ring-shaped header 1 passing through, and the chimney cap 7
was ejected from. On the other hand, water supplied from the water supply port 11 passes through the water pipe 3 according to the arrow B and is supplied from the hot water supply port 12, and heat exchange is performed between the upper and lower annular headers 1<2 and the water pipe 3. Compared to a jacket type heat exchanger with a heat exchange chamber of the same size, this type uses water tubes 3 and has a wider heat transfer area, which is advantageous in terms of thermal efficiency, but it also has the following problems. Was.

(1) Energy of combustion gas 10 generated in combustion chamber 5
was absorbed by the heat insulating material 4 that formed the combustion chamber 5, and was radiated into the atmosphere as heat loss.

(2) Since the combustion gas 10 was absorbed by the heat insulating material 4 that formed the combustion chamber 5, the atmosphere in the combustion chamber 5 became extremely high temperature. Burner 6 facing combustion chamber 5
Because of this high-temperature atmosphere, the temperature force (higher) makes it more susceptible to thermal deterioration.
There was a risk of flames escaping from the joints and gaps.

Purpose of the Invention The present invention solves such conventional problems, and by forming the combustion chamber with a water-cooled wall in which a heat shield plate is bonded to the inside of the water pipe and a water pipe header, the inner surface of the combustion chamber is made into a heat transfer surface. The purpose is to improve thermal efficiency, prevent thermal deterioration of the combustion chamber and burner, and increase safety.

Structure of the Invention In order to achieve this object, the present invention provides a multi-tubular once-through heat exchanger in which a gap is provided between the upper and lower annular headers on the inside of the water tube, and a heat shield plate having a concentric circle with the upper and lower annular headers is provided. The combustion chamber is formed by the water-cooled wall and the header, which are joined together, and the combustion gas path is formed by the baffle body and the outer wall.The burner is connected to the water-cooled wall and the water pipes, and the combustion chamber is faced from between the water pipes. It is something.

With this configuration, the inner surface of the combustion chamber can be used as a heat transfer surface, improving thermal efficiency, and since the combustion chamber is formed of a header and a water-cooled wall, the atmospheric temperature of the combustion chamber can be kept low. Furthermore, since the bar is connected to the water-cooled wall and water pipes and faces the combustion chamber, the burner is water-cooled, which prevents thermal deterioration of the burner.The water-cooled wall prevents the combustion flame from blowing out of the combustion chamber. The more you do, the more safety you have. In addition, a circulation flow of combustion gas occurs through the gap provided between the heat shield plate, the baffle body, and the header.
Fuel and combustion air are premixed, allowing stable combustion.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 2(,) and 2(b). The combustion chamber 5 is formed of a water-cooled wall in which upper and lower annular headers 1.2 and a heat shield plate 13 having a concentric circle are joined to the inner side of the lower-shaped header 2 and the water pipe 3. The combustion chamber is faced from between the water pipes 3. A cylindrical water pipe body 9 with closed upper and lower ends is suspended so that it is located inside a plurality of groups of water pipes 3 arranged in a ring shape.
It is supported by the chimney cover 7 via a metal fitting 14. An outer wall 15 is provided on the outside of the 3 groups of water pipes with a heat insulating plate or the like, and the upper end of the outer wall 12 is in close contact with and joined to the lower header 1.2,
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It forms a closed structure. Note that the same members as in FIG. 1 are given the same numbers.

In the above configuration, the combustion gas 10 at the temperature that is generated by the burner 6 flows from the combustion chamber 6 to the baffle hole 9 as shown by arrow B.
The combustion gas passes through the combustion channel 8 formed by the outer wall 15, the ring-shaped header 1, and is discharged from the chimney cap 7. On the other hand, water supply port 11
The water is supplied from the hot water supply port 12 through the water pipe 3 according to the arrow C, and heat exchange is performed by the upper and lower annular headers 1 and 2 and the water pipe 3.

Joined to the water pipe 3 at the water cooling wall forming the combustion chamber 5 □
The heat shield plate 13 functions as a plate-like fin, and the inner surface of the combustion chamber 5 is used as a heat transfer surface, thereby improving thermal efficiency. In addition, the water-cooled wall lowers the atmospheric temperature of the combustion chamber 5, and the water-cooled wall and water pipe 3 to which the nozzles 6 are connected prevent thermal deterioration of the burner 6. The walls prevent combustion flames from blowing out, increasing safety.

Since the diameter of the upper opening of the heat shield plate 13 is made smaller than the diameter of the combustion chamber 5, a circulating flow is created in which the combustion gas 1O descends along the heat shield plate 13 within the combustion chamber 5. In addition, since the heat shield plate 13 is connected to the water pipe 3 with a gap between the upper and lower annular headers 1.2, the upward flow of the combustion gas 10 causes the combustion gas path 8 at the bottom of the baffle body 9 to A pressure difference is created between the bottom-shaped header 2 and the gap E between the heat shield plates, and a circulating flow of the combustion gas 10 is created.

This circulation flow premixes fuel and combustion air, allowing stable combustion.

Next, a second embodiment of the present invention will be explained using FIG. 3 (81, (bl). The difference in FIG. Also in this configuration, the above effects can be obtained by joining the burner 6 to the shoe-shaped header 2.

Effects of the Invention As described above, according to the water tube boiler of the present invention, the following effects can be obtained while maintaining the high thermal efficiency of the multi-tube boiler.

(1) Since the combustion chamber is formed of water-cooled walls, the inner surface of the combustion chamber can be used as a heat transfer surface, improving thermal efficiency.

(2) Since the combustion chamber is formed with a water-cooled wall, the atmospheric temperature of the combustion chamber can be kept low, and since the burner is still water-cooled, thermal deterioration of the burner can be prevented.

(3) Safety is improved because the water-cooled wall prevents combustion flames from blowing out.

(4) The circulating flow of combustion gas premixes the fuel and combustion air, allowing stable combustion.

[Brief explanation of the drawing]

Figure 1 (a) shows the conventional multi-tubular once-through heat exchanger
Figure 1(b) is a cross-sectional view taken along the line A- in Figure 1(a), and Figure 2(a) is a vertical cross-sectional view of a water tube boiler according to an embodiment of the present invention. Front view, Figure 2 (
b) is a cross-sectional view taken along the line A-A' in FIG. 2 (fi);
Figure 3 (, 1 is a longitudinal cross-sectional view of a water tube boiler according to a second embodiment of the present invention, Figure 3 (b) is a line AA' in Figure 3 (a)
FIG. DESCRIPTION OF SYMBOLS 1-... Stop ring-shaped header, 2-... Shoe-shaped header, 3... Water pipe, 5-... Combustion chamber, 6 Burner, 1
3. Heat shield plate.

Claims (1)

[Claims] A plurality of water pipes are installed in a ring shape between the annular headers arranged above and below, and a heat shield with a concentric circle with the upper and lower annular headers is installed inside the water pipes near the burner section as seen from between the water pipes. A water tube type boiler or larder in which a combustion chamber is formed by a water-cooled wall made by joining plates with a gap between the stop ring header and the lower ring header.
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