JPH0722561Y2 - Convection evaporation tube of waste heat boiler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a convection evaporation tube of a waste heat boiler that uses waste heat of a furnace.

[Prior Art] A waste heat boiler that uses the waste heat of a furnace to generate steam is equipped with an evaporation pipe in the flue of the furnace, and the water in the evaporation pipe is removed by the heat of the waste gas of the furnace passing through the flue. It is configured to heat and generate steam. The evaporator pipe is arranged on the wall of the furnace to use the radiant heat transfer from the exhaust gas when the temperature of the exhaust gas is high, and inside the flue to use the convective heat transfer when the exhaust gas temperature is low. ing.

FIG. 2 (a) shows a conventional convection evaporation pipe arranged in a flue, in which 1 is a flue, 2 is its ceiling, 3 is its lower part, 4 is a convection evaporation pipe, and 4a is a straight pipe. , 4b are curved pipes, 5 is an arrow indicating the direction of progress of waste gas, and 6 is dust.

As shown in the figure, the convection evaporation pipe 4 arranged in the flue 1
Is a combination of a straight pipe 4a with an outer diameter of 38.1 mm and a curved pipe 4b.
It has a pitch t1 of 120 mm and is bent up and down. The waste gas flows in the direction of arrow 5 and exchanges heat with the evaporation pipe 4.

[Problems to be Solved by the Invention] Generally, since the waste gas of the furnace contains a large amount of dust 6, the pitch t1 of the straight pipe 4a of the evaporation pipe is as described above.
If it is about 120 mm, as shown in FIG. 2 (b), the dust 6 is deposited and adhered to the lower curved pipe portion and grows with time.
When the dust 6 grows, it blocks the boiler flue and hinders the operation of the furnace body. To prevent this, the boiler evaporation pipe is periodically hammered by a hammering device to remove the dust adhering to the evaporation pipe. On the other hand, the inside of the furnace is regularly inspected, and the dust 6 attached to the upper parts of the straight pipe 4a and the curved pipe 4b by the worker
Is knocking off. However, performing such work in a poor working environment is a problem in terms of occupational safety and health, and tapping the evaporation pipe with a steel rod to remove dust is to shorten the life of the evaporation pipe 4. It's a problem.

The present invention has been made to solve the above problems of the conventional waste heat boiler, and an object of the present invention is to provide a convection evaporation tube in which the number of inspections and cleanings in the furnace is reduced and the life of the evaporation tube is extended.

[Means for Solving the Problems] In the convection evaporation pipe of the waste heat boiler according to the present invention, the convection evaporation of the waste heat boiler in which a plurality of straight pipes are connected in a continuous U shape by curved pipes arranged at the upper and lower ends thereof. In the pipe, the curvature of the curved pipe arranged at the lower end is set to be large, and the straight pipes adjacently connected by the curved pipe are made as close to each other as possible.

[Operation] In the convection evaporation pipe of the waste heat boiler configured as described above, the curvature of the curved pipe arranged at the lower end side of the straight pipe is set to be large, and the straight pipes adjacent to each other by the curved pipe are connected to each other. Since they are made as close to each other as possible, dust does not accumulate on the curved pipe section arranged on the lower end side.

[Embodiment of the Invention] FIG. 1 shows an embodiment of the present invention. (A) is a front view of a convection evaporation pipe, (b) is an enlarged view of a lower curved pipe, and 1 to 5 are conventional boilers. Same or equivalent parts, 10 is a convection evaporation tube, 10
a is a straight pipe, 10b is an upper curved pipe, and 11 is a lower curved pipe.

In the figure, the convection evaporation tube 10 is composed of a straight tube 10a having an outer diameter of 38.1 mm and a plate thickness of 5 mm, an upper bent tube 10b and a lower bent tube 11, and a lower bent tube.
A straight pipe connected with the lower curved pipe 11 by setting the curvature of 11 large
The pitch t2 of 10a is 42.5 mm. Thus, the pitch t2 of the straight pipe 10a connected by the lower curved pipe 11 is 42.5 m.
Since it is m, which is smaller than the conventional pitch t1 120 mm, the dust 6 hardly deposits and adheres to the curved pipe 11. For this reason, the number of times and the working time for knocking off dust in the furnace can be shortened.

[Advantage of the Invention] In the present invention, the curvature of the curved pipe arranged at the lower end side of the straight pipe is set to be large, and the straight pipes adjacently connected by the curved pipe are made as close to each other as possible. Almost no dust accumulated and adhered on the curved pipe. Therefore, it took 30 to 60 minutes once every two days for a worker to knock off dust in a poor working environment when inspecting a furnace.
It only takes 15 to 20 minutes once a day, which means that the number of times of work and work time can be greatly reduced.

Moreover, since the evaporation tube is not hit, it is possible to extend the life of the evaporation tube.

[Brief description of drawings]

1 (a) is a front view of a convection evaporation tube which is an embodiment of the present invention, FIG. 1 (b) is an enlarged view of a lower curved tube, and FIG. 2 (a) is a front view of a conventional convection evaporation tube. The same (b) is an enlarged view of the lower curved pipe. In the figure, 10 is a convection evaporation tube, 10a is its straight tube, 10b is a bent tube, and 11 is a lower bent tube. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. A convection evaporation pipe of a waste heat boiler, wherein a plurality of straight pipes are connected in a continuous U shape with curved pipes arranged at the upper and lower ends thereof, and the curvature of the curved pipes arranged at the lower end is set to be large. A convection evaporation pipe for a waste heat boiler, characterized in that straight pipes connected adjacently by curved pipes are arranged as close as possible.