JPS6017971B2 - water tube boiler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water tube boiler with improved heat transfer.

Conventionally, both the upper header and the lower header are formed in an annular shape, and the upper and lower headers are connected by a large number of inner water pipes, and these inner water pipes are arranged as annular water pipe arms with a slight gap. The upper and lower pipe headers are connected by outer water pipes, and these outer water pipes are arranged as annular water pipe walls with a slight gap to direct combustion gas from the combustion chamber at almost right angles to the water pipes.
Water tube boilers designed to allow water to flow through the water have been known.

The object of the present invention is to create a new structure by organically combining conventionally known structures, and to provide a water tube boiler with improved heat transfer.

In accordance with the above object, the structure of the present invention is such that the diameter of the outer water pipe is larger than that of the inner water pipe, the pitch angle of the inner water pipe is made equal to the pitch angle of the outer water pipe, and the gap between the inner water pipe and the pitch angle of the outer water pipe are made larger than that of the outer water pipe. The feature is that the gap is narrower.

In addition, the diameter of the outer water pipe is made larger than that of the inner water pipe, the pitch angle of the inner water pipe is made equal to the pitch angle of the outer water pipe, and the gap between the outer water pipe is narrower than the gap between the inner water pipe. It is characterized by a partition wall placed at the bottom of the combustion chamber and installed inside the lower header. Hereinafter, this invention will be explained based on the drawings.

Both the upper header 1 and the lower header 2 are formed in an annular shape. These upper and lower headers 1 and 2 have a large number of inner water pipes 3.
These inner water pipes 3 are arranged as an annular water pipe wall with a slight gap. Furthermore, the upper and lower pipe heads 1 and 2 are separated by outer water pipes 4 having a larger pipe diameter than the inner water pipes 3, and these outer water pipes 4 are arranged as annular water pipe walls with a slight gap. As shown in Fig. 3, the pitch angle A of the inner water pipe 3 and the pitch angle B of the outer water pipe 4 are made horizontally so that they are the same, and the pitch angles on the inner and outer sides are shifted by half a pitch. , the gap opening of the outer water pipe 4 is narrower than the gap A of the inner water pipe 3.A boiler outer wall 5 is provided at intervals on the outside of the water pipe arm.The water pipe of the inner water pipe 3 A combustion chamber 6 is formed within the wall. A combustion device 7 is provided inside the upper header 1. Both ends 8 of each water pipe 3, 4 have a small diameter.
They are welded to the tube sheets of the upper header 1 and the lower header 2, respectively, by inserting iron into them. A partition wall 9 is provided at the bottom of the combustion chamber 6.
is arranged, and a flue 10 is provided inside the lower pipe header 2. That is, the structure is such that the combustion gas passes through the gaps between the water tubes twice, from the inside to the outside and from the outside to the inside. Next, to explain the operation, the combustion gas generated in the combustion chamber 6 first exchanges heat with the inner water tube 3 by jugular heat transfer, flows almost perpendicularly to the water tube, and is formed by a group of water tubes.

It passes through the gap while exchanging heat by convection heat transfer, passes through the gap in the water pipe group, reaches the dust pipe provided inside the lower pipe header 2, and reaches the chimney provided in a part of the dust pipe 10. (not shown) at a low temperature. The combustion gas flow rate and heat transfer are approximately proportional to each other.

In other words, an increase in flow rate promotes heat transfer. When water tubes with the same diameter are arranged in an annular row at the same pitch, the gap between the outer water tubes becomes larger than the gap between the inner water tubes, and the combustion gas flow rate decreases significantly due to the decrease in gas temperature. However, in this invention, the diameter of the outer water tube is made larger than that of the inner water tube, so the gap between the inner water tube and the gap between the outer water tube can be arbitrarily selected.
Furthermore, the gap between the inner water tube and the outer water tube can be selected arbitrarily, three narrow gaps can be formed, and good heat transfer can be achieved on all electric heating surfaces.

As explained above, this invention has a configuration in which the pitch angles of the inner and outer water tubes are the same, and the diameter of the outer water tube is larger, so that the cross-sectional shape of the combustion gas flow path is regularly arranged, and it is well-organized. Heat transfer is achieved on all heat transfer surfaces, and a small, highly efficient water tube boiler can be provided.

Furthermore, since the structure is such that a partition wall is provided so that the combustion gas passes once again through the lower gap of the water tube in the low-temperature section, a small and highly efficient water tube spoiler can be provided.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view, FIG. 2 is a cross-sectional view, and FIG. 3 is a partially enlarged cross-sectional view. ] is the upper header, 2 is the lower header, 3 is the inner water pipe, 4 is the outer water pipe, 5 is the boiler outer wall, 6 is the combustion chamber, 7 is the combustion device, 9 is the bulkhead, 10 is the flue, A is the inner water pipe pitch angle, B
is the pitch angle of the outer water tube, A is the gap between the inner water tube, and mouth is the gap between the outer water tube. Figure 2 Figure 3 Figure 1

Claims (1)

[Claims] 1. Both the upper header 1 and the lower header 2 are formed in an annular shape, and the upper and lower headers 1 and 2 are connected by a large number of inner water pipes 3, and these inner water pipes 3 have a slight gap. Further, the upper and lower headers 1 and 2 are connected by an outer water pipe 4 having a larger pipe diameter than the inner water pipe 3, and these outer water pipes 4 are arranged as an annular water pipe wall with a slight gap. It is arranged as a water pipe wall and configured so that the pitch angle A of the inner water pipe 3 and the pitch angle B of the outer water pipe 4 are the same, and the gap B of the outer water pipe 4 is narrower than the gap A of the inner water pipe 3. A water tube boiler characterized by being configured as follows. 2 Both the upper header 1 and the lower header 2 are formed in an annular shape, and the upper and lower headers 1 and 2 are connected by a large number of inner water pipes 3, and these inner water pipes 3 are formed by an annular water pipe wall with a slight gap. Further, the upper and lower headers 1 and 2 are connected by an outer water pipe 4 having a larger pipe diameter than the inner water pipe 3, and these outer water pipes 4 are arranged as an annular water pipe wall with a slight gap. , the pitch angle A of the inner water pipe 3 and the pitch angle B of the outer water pipe 4 are configured to be the same, the gap B of the outer water pipe 4 is configured to be narrower than the gap A of the inner water pipe 3, and the water pipe wall A boiler outer wall 5 is provided at intervals on the outside of the boiler, a combustion chamber 6 is formed within the water pipe wall of the inner water pipe 3, a combustion device 7 is provided inside the upper header 1, and a partition wall 9 is provided at the bottom of the combustion chamber 6. A water tube boiler characterized in that a flue 10 is provided inside a lower header 2 by arranging a flue 10.