JPS6093244A - Water tube boiler - Google Patents

Abstract

PURPOSE:To improve the durability, the reliability and the heat exchange efficiency of the titled boiler by encircling a combustion chamber and a heat exchange chamber by a water cooled wall consisting of a shell frame, water tubes and upper and lower annular headers. CONSTITUTION:A plurality of water tubes 3 are provided upright in a ring shape between a plurality of upper and lower annular headers 1 and 2. The water tubes 3 are formed into a cylindrical shape at the upper and lower annular headers 1 and 2, and are bonded to the upper and lower annular headers 1 and 2. Respective water tubes 3 are bonded to the outside of the shell frames 4 having corrugated zigzag surfaces covering clearances between water tubes 3. Further, the shell frames 4 form a combustion chamber 5 and a heat exchange chamber 6. Combustion gas burning in a burner 7 passes through bubbles 8 provided concentrically and circularly on the water tubes 3 and clearances G and G' between the shell frames 4 having corrugated zigzag surfaces, and are discharged into the atmospheric air via an exhaust lid 9. Thus, it is possible to obtain high reliability, safety and durability with respect to the combustion flame and combustion gas of high temperature.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a wood boiler used for hot water supply.

Conventional example (14 structure and its problems) Conventionally, this type of water tube boiler, as shown in Fig. 1, has a plurality of water tubes 3 erected in a ring shape between the upper and lower annular headers 1 and 20 for heat exchange. It made up a vessel.

The combustion gas combusted by the burner 4 was flowing between the baffle 5 and the water pipe 3 according to the arrow A.

On the other hand, water supplied from the water supply 1''6 passed through the water pipe 3 according to the arrow B, and was supplied from the hot water supply lower.

In this configuration, the surface area of the water 73 must be increased in order to secure a heat transfer area, which increases the length and number of water pipes 3, increasing material costs and manufacturing man-hours. In addition, since the combustion gas passes between the water pipe 3 and the heat shield plate 80 and exchanges heat with the water pipe 3, the surface temperature of the heat shield plate 8 is 400 to 700°C.
It is necessary to improve the heat insulating performance of the heat insulating layer 9 that covers the outside of the heat shield plate 8, resulting in problems such as a lack of durability and reliability.

Furthermore, as shown in Fig. 2, in a once-through boiler using a water-cooled pipe 3 connected to a shell 2 surrounding a combustion chamber 1, the combustion gas combusted in a burner 4 passes through the combustion chamber 1 in the direction of arrow A and passes through the combustion chamber 1. Heat is exchanged mainly in the fin heat exchanger 5. on the other hand,
The water supplied from the water supply port 6 flows through the water cooling pipe 3 according to the arrow B.
The hot water was passed through the fin heat exchanger 5 and supplied from the hot water supply lower. In this configuration, the heat transfer area can be easily secured by the plate-shaped fin heat exchanger 5, but in order to maintain the durability of the fin heat exchanger 5, the temperature at the tip of the plate-shaped fin must be 250°C or less. , the height H of the combustion chamber must be increased. For this reason, the pipe length of the water-cooled vibrator 3 becomes longer, the pipe resistance increases, and the slope of the wound water-cooled pipe 3 becomes smaller, making it difficult for air bubbles generated during cooling of the body frame 2 to escape, making it more likely to cause bumping. I had a problem.

OBJECT OF THE INVENTION The present invention solves such conventional problems, and improves durability,
The purpose is to improve reliability and heat exchange efficiency.

Structure of the Invention In order to achieve this object, the present invention provides a body frame having a plurality of water pipes erected in a ring shape between upper and lower annular headers, and having a wavy and meandering surface covering the gap between the water pipes. A water pipe is connected to the outside of the shell, and combustion gas is allowed to flow into the shell frame.

With this configuration, combustion gas passes through the water-cooled wall having a wavy meandering surface, improving heat exchange efficiency and reliability of the equipment.

Description of examples An embodiment of the present invention will be described below with reference to FIG.

A plurality of water pipes 3 are erected in a ring shape between upper and lower annular headers 1 and 2. The water pipe 3 has a cylindrical shape at the upper and lower annular headers 1 and 2, and is joined to the upper and lower annular headers 1 and 2. Further, each water pipe 3 is joined to the outside of a body frame 4 having a wave-shaped meandering surface that fills the gap between the water pipes 3. A combustion chamber 6 and a heat exchange chamber 6 are formed by the body frame 4. The combustion gas combusted in the burner 7 at the bottom of the combustion chamber 5 flows in the direction of arrow A between the baffle 8 provided concentrically with respect to the ring-shaped water pipe 3 and the body frame 4 having a wavy meandering surface. It passes through the gaps G and d, and is discharged into the atmosphere via the exhaust cover 9.

On the other hand, the flow on the water side follows arrow B, and after being supplied from the water supply port 10, the hot water is exchanged with the combustion gas while rising inside the water pipe 3, and is discharged from the hot water supply port 11.

Since the body frame 4 is connected to the upper and lower annular headers 1 and 2 and the water pipe 3, the combustion gas passes through the water-cooled wall.
Reliability against high-temperature combustion flames and combustion gas is improved, and the thickness of the heat insulating material 12 covering the outside of the shell frame 4 can also be reduced.

In addition, the body frame 4 has a wavy, meandering structure, and is closely joined to the water pipe 3 by brazing, etc., so the heat transfer area is small.
Heat transfer efficiency increases and heat exchange efficiency with combustion gas improves.

Furthermore, since the water pipe 3 is installed vertically, bubbles that occur when the temperature of the hot water rises due to heat exchange with the combustion gas can be prevented.
It can easily pass through the stop ring header 1 and reduce bumping.

Effects of the Invention According to the water tube boiler of the present invention, the following effects can be obtained.

(1) High reliability can be obtained.

By surrounding the combustion chamber and heat exchange chamber with a water-cooled wall consisting of a body frame, water pipes, and upper and lower annular headers, high-temperature combustion flame,
Provides reliability, safety, and durability against combustion gas.

(2) High thermal efficiency can be obtained.

The corrugated body frame is closely attached and joined to the water pipe by brazing, etc., so it acts as a plate-like fin for the water pipe.
By increasing the height of the corrugations, a sufficient heat transfer area can be easily obtained and the heat exchange efficiency can be improved.

(3) Bumping and after-boiling can be reduced.

Bubbles that are generated when the temperature of the hot water rises due to heat exchange with the combustion gas easily move continuously into the stop ring header because the water pipes are installed vertically.

Therefore, bumping that occurs at low flow rates is reduced.

In addition, because heat exchange is performed efficiently in the water-cooled wall,
Heat transfer loss to the outside of the water-cooled wall is reduced, and the insulation material covering the water-cooled wall can be made thinner. The heat capacity of this waste heat exchanger is also reduced, and after-boiling after combustion is stopped can be reduced.

[Brief explanation of drawings]

Figures 1a and b are longitudinal and horizontal sectional views of a conventional water tube boiler, Figure 2 is a longitudinal sectional view of another conventional example, and Figures 3a and b.
1 is a longitudinal sectional view and a horizontal sectional view showing an embodiment of a water-cooled boiler according to the present invention. 1...Two annular header, 2...Lower annular header, 3...Water layer, 4 - Body frame, 5...Combustion chamber, 6... ...Heat exchange room. Name of agent: Patent attorney Satoshi Nakao 9) and one other person Figure 1 (a,) (b) Figure 2

Claims (1)

[Claims] A plurality of water pipes are installed in a ring shape between the annular headers placed above and below, and the water pipes are joined to the outside of the body frame, which has a wavy meandering structure that covers the gap between the water pipes. A water tube boiler that allows combustion gas to flow into the boiler.