JPS60232402A - Drum body with fin for mutitubular type once-through boiler - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a finned heat transfer structure used in a multi-tubular once-through boiler and the like.

It is generally known that fins are provided on the heat transfer surface of boilers and the like to improve heat transfer efficiency.

Conventionally, fins were attached to the heat transfer surface by welding, but when there are many fins such as in a multi-tube once-through boiler, especially when a large number of fins are attached in the circumferential direction of the water tube, The number of welding man-hours was good.'' The strike was high. Moreover, since water pipes are deformed due to welding strain, multi-pipe construction in which many water pipes are arranged in a circular ring (in once-through boilers,
Assembly and IJD work were difficult. In addition, in welding, there are cases where the penetration of the fin and the matrix at the fin base is insufficient, and therefore the expected fin efficiency cannot be obtained.

In view of the above points, the present invention aims to reduce the number of man-hours required when providing fins on a heat transfer surface, and to improve fin efficiency by ensuring close contact between the sun and moon at the base of the fins and the fins. The upper and lower headers are both formed in an annular shape, and the upper and lower headers are connected by a number of vertical water pipes.
These main pipes are arranged as two concentric annular water pipe walls with an interval of d5 in the radial direction, and a combustion gas passage is formed between the inner annular water pipe wall and the outer annular water pipe wall. An opening extending over the entire length of the pipe is provided in the inner annular water pipe wall to communicate the combustion chamber with the combustion waste passage, and an opening extending over the entire length of the pipe is provided in the outer annular water pipe wall to communicate the combustion nozzle. A multi-pipe member that communicates the duct and flue? In the boiler j5, a large number of fins are arranged in the circumferential direction on the inner annular water tube wall d3 and /' or on the part of the outer annular water tube wall facing the combustion gas passage, and the annular water tube wall is This is a finned body of a multi-tubular once-through boiler in which a layer of molten metal such as molten aluminum is provided between the fins and the fins.

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a vertical sectional view showing an embodiment of the invention, and FIG.
3 is a partially enlarged cross-sectional view, FIG. 4 is a vertical cross-sectional view of the water tube fin portion, FIG. 5 is a cross-sectional view of the water tube fin portion, and FIG. 6 is a cross-sectional view of the water tube fin portion according to another embodiment. be. In the figure,
13, the upper header 1 and the lower header 2 are both formed in an annular shape. The upper and lower headers 1.2 are connected by a number of vertical water pipes, which are arranged 8 in two concentric annular water pipe walls spaced radially apart by J3. A combustion waste passage 5 is formed between the inner annular water tube wall 3 and the outer annular water tube wall 4 . A combustion device 6 is partially provided inside the header 1. If desired, this combustion device 6 can be placed anywhere by utilizing the space formed inside the lower header 2. 7 in V is the annular water tube wall 3, which is a combustion hole formed inside the inner annular water tube wall J3;
Both ends of each of the water tubes 4 become diameter-reduced portions 8, which are respectively fitted into the tube plate tH of the lower header 1 and the pipe machine of the lower header 2 and welded. An opening 9 is provided throughout the tube of the inner annular main pipe 3'8, providing communication between the combustion chamber 7 and the combustion waste passage. An opening 10 is provided in the outer annular water tube wall 4 over the entire length of the tube, which communicates the combustion gas passage 5 with the flue 11.

It is also desirable to connect the torpedoes of the outer annular water tube wall 4 with spacers so that the pitch angle of the inner water tube is the same as the pitch angle of the outer water tube. Incidentally, when each wood pipe of the inner annular water pipe 'i4 is also connected by the spacer 15, the outer spacer may be made longer.

A large number of fins 12 are attached in the circumferential direction to portions of the inner annular water tube wall 3 and the outer annular water tube wall 4 facing the combustion waste passage Yg5. A slight gap is provided between the annular water pipe wall and the fin, and a molten metal layer 13 of iRffi!! aluminum is formed between the annular water pipe wall and the fin. In 6th episode, the gap between the WakaF and the annular water pipe wall and the fins are temporarily attached using static welding, etc., and the can body consisting of the upper and lower pipe headers, the inner and outer annular water pipe walls J5, and a large number of fins is assembled. By putting the metal i8 into the molten layer, the molten metal penetrates and is formed.The shape of the fin is shown in Fig. 5.
Curvature R1, R of the part n1 on the annular water pipe wall as shown in 6
) to be larger or smaller than the outer diameter r of the water pipe, it becomes easier to temporarily attach (14) by stud welding or the like.

In addition, by making the curvature of the fin on the side facing the annular water pipe wall equal to the curvature of the fin on the side facing the annular water pipe wall, the temporary removal can be carried out efficiently and efficiently. I can write. In addition, in the embodiment, fins are attached to the inner and outer water pipe walls. However, the fins may be attached only to the inner water pipe wall, or the fins may be attached only to the outer water pipe wall. may be installed.

To explain the effect of the above-mentioned configuration, the combustion scum generated in the combustion stage 7 first exchanges heat with the inner annular water tube wall S by radiation heat transfer, and then the combustion scum generated in the combustion stage 77 ) I branch toward the opening 9, flow through the combustion gas passage 5 almost at right angles to the longitudinal direction of the tube, in a direction across the tube, merge at the opening 10, and exit from the flue 117) to the outside. be discharged. Since the combustion scum passages are provided with fins 12, the heat is good.

The present invention is constructed as described above, and since a layer of molten metal such as aluminum is formed between the annular water tube wall and the fin, the thermal conductivity between the fin and the annular water tube wall is improved. The fin efficiency is highly improved, and the effective heat transfer area is increased compared to a welded platform. Seventeenth, the number of welding steps is shortened, and furthermore, the can body can be manufactured easily because there is no need for water pipes to be deformed due to welding of fins as in the conventional method. .

[Brief explanation of drawings]

FIG. 1 shows a vertical li/1ilII1 embodiment of the present invention.
Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a partially enlarged cross-sectional view,
FIG. 4 is a longitudinal cross-sectional view of the water tube fin portion, FIG. 5 is a cross-sectional view of the water tube fin portion, and FIG. 6 is a cross-sectional view of the water tube fin portion according to another embodiment. 1. Upper header (! 2. Lower header 3, inner annular water tube wall 4. Outer annular water tube wall 5, combustion gas passage 6. Combustion device 7, combustion end 8. Reduced diameter part of water tube 9. Inner annular water pipe wall opening 10, outer annular water pipe wall opening 1], flue 12. Fin 13, molten metal layer 14. Temporary attachment is made by the patent applicant, representative of Miura Kogyo Co., Ltd. Yasuzu Miura 1 Figure 2 Figure 4 □1' Figure 5 Figure 6

Claims (1)

[Claims] Both the upper header 1 and the lower header 2 are formed in an annular shape, and the upper and lower headers 1.2 are connected by a number of vertical water pipes, and these water pipes are connected to each other by two concentric annular water pipes spaced apart in the radial direction. arranged as walls 3, 4, forming a combustion gas passage 5 between the inner annular water tube wall 3 and the outer annular water tube wall 4, and forming a combustion gas passage 5 in the inner annular water tube wall 3 over the entire length of the tube. An opening 9 is provided to communicate the combustion chamber 7 with the combustion gas passage 5, and an opening 10 extending over the entire length of the tube is provided in the outer annular water tube wall 4 to communicate the combustion gas passage 5 with the flue 11. In a multi-tubular once-through boiler, fins 12 are provided on the inner annular water tube wall 3 and/or the outer annular water tube wall 4 in the portion facing the combustion gas passage 5.
A finned body for a multi-tube once-through boiler, characterized in that a large number of water tubes are arranged in the circumferential direction, and a molten metal layer 13 such as molten aluminum is provided between the annular water tube walls 3 and 4 and the fins.