JPS602562B2 - water tube boiler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a boiler that can firmly support a superheater, economizer, etc. placed in a flue.

BACKGROUND OF THE INVENTION Boilers in which a combustion chamber and a flue following the combustion chamber are formed into a body with a water tube wall to improve the efficiency of heat recovery have become popular as small and medium capacity boilers for factories or private power generation.

In this type of boiler, in order to further increase heat recovery efficiency, a type of boiler is provided in which a group of transmission tubes such as a superheater or energy saver is arranged in the dust path, but in this case, the wall surface is composed of water tubes. Because of this, there were various restrictions on installing heat exchanger tubes, and there were also problems with the strength of the boiler itself. FIG. 1 shows the arrangement of heat exchanger tube groups in a conventional boiler. In the figure, a primary superheater 4, a secondary superheater 5, and a energy saver 6 are arranged in order from the top in a bonito path 3 of a boiler main body 1. Here, since the rear wall la that partitions the boiler furnace 2 and the flue 3 is composed of water tubes, the load of these heat transfer tube groups cannot be supported by the rear wall la, and the head of each heat transfer tube group is da4a
, 5a, and 6a are all made to protrude outside the boiler outer wall lb, and each heat exchanger tube is supported in a cantilevered manner. As a result, the strength of supporting the heat exchanger tubes was unstable, and it was impossible to install heat exchanger tubes with a large heat transfer area, that is, a large weight. Furthermore, since the upper and lower headers of each heat exchanger tube group are both placed outside,
All the heat transfer tubes connected to these headers must also be inserted through the outer wall 1b, which places great restrictions on the arrangement of water tubes in the outer wall, which is a water-cooled wall. An object of the present invention is to provide a boiler that can eliminate the above-mentioned problems, firmly support heat exchanger tubes placed in a canal, and increase the strength of the boiler itself.

In short, this invention bends a part of the water pipe that makes up the rear wall of the boiler toward the furnace side, and attaches a header to this bent part to function as a backstay and increase the strength of the rear wall itself.
In short, the present invention relates to a boiler configured so that the header is supported by a beam of a boiler-type frame to bear part of the load of the heat exchanger tube group.

Embodiments of the present invention will be described below with reference to the drawings. In FIG.
The header 5a of the superheater 5 and the economizer 6 is bent to form a bent portion 7, and the header 5a of the superheater 5 and the economizer 6 is bent to form a bent portion 7. Place 6a. FIG. 3 shows details of this bend. In the figure, 8 is a water pipe L, 9 is a membrane bar that is interposed between each water pipe 8 and welded to each water pipe to form a membrane structure as a whole, and the rear wall a is a water sill wall that has this membrane structure. ing. Every other water pipe 8 is bent toward the furnace 2 in a substantially dogleg shape (indicated by reference numeral 8a).
By bending the membrane bar 9 together with the bent water tubes in the parentheses, the bent portion 7 is formed by these bent water tubes and the membrane bar 9.On the other hand, the remaining water tubes are arranged vertically without being bent (as shown by reference numeral 8b). ).One header 5a of the superheater 5 is connected to this bent portion 7.
It is inserted and placed in the. In this case, the vertical water pipe 8b is the head 5
Is a the bent part? It serves as a support to prevent it from falling off, and is also used as a load-bearing member to reinforce the water wall pipe. In addition, the header 5a is not fixed by welding or the like to any of the water pipes and the membrane bar 9, so that no stress is generated due to the difference in elongation between the rear wall a and the header 5a. Even when the water pipe 8 and the header 5a are displaced due to this difference in expansion, the header 5 is
This is a support plate formed in the longitudinal direction of a. On the other hand, the other header 5a' (FIG. 2) has a rear wall l, similar to the conventional type shown in the wing diagram.
Although the projecting cost may be left on the side b, it is placed in the flue as shown in the figure, and both ends of the boiler protrude from the side wall of the boiler, and are supported by beams or the like constituting the boiler frame. In this case header 6
Only both ends of a' will be inserted through the wall and held by the frame. Since a large number of heat transfer tubes do not need to be inserted through the wall surface, the boiler wall structure can be simplified without any insertion portions. Third
Although the figure has mainly been described with reference to the secondary superheater installation part, the header 6a of the economizer 6 is similarly arranged and supported at another bent part.

In addition, in the case shown in FIG. 3, every other water pipe 8 is a straight pipe 8b, but the number of straight pipes 8b may be smaller than this, for example, every other two or three straight pipes. You can also answer the question directly.

As mentioned above, the bent part 7 performs an important function for header counterfeiting, and it is also possible to form the bent part 7 and place the header there as a reinforcing member, or to use this header with a boiler frame or the like. It can be supported to increase the strength of the entire wall surface.

Next, the primary superheater 4 may be constructed in the same machine as the secondary superheater 5 described above, with one header disposed at the bend, but one header 4a may be placed in the boiler as shown in the diagram. You can also support the ceiling part with a suitable tube and place it on the top of the boiler, and support one end with a beam of the rear IC.

In addition, the code in the figure is Ikukawa Mapoira Drum! 2 is a downcomer. By implementing this invention, it is possible to support heat transfer tubes such as superheaters and economizers placed in the flue, and to strengthen the boiler structure by reinforcing the rear wall tubes. Heat exchanger tubes with a large weight can be installed, increasing heat recovery efficiency, reducing the number of hems located in the leech path, and reducing dust accumulation.

Furthermore, the rear wall can be reinforced by forming a bent part in the rear wall of the furnace and housing a header therein, and this can be supported by a boiler frame beam or the like, so that the boiler as a whole can have a strong structure.

[Brief explanation of the drawing]

The schematic diagram is a cross-sectional view of a conventional water tube boiler, FIG. 2 is a cross-sectional view of a water tube boiler according to the present invention, and FIG. 3 is a partial perspective view of the rear wall centered on the bent portion. Turtle... Boiler body, la... Rear wall, 2... Furnace.
3... Flue, turtle, 5... Superheater, 5a...
...Header t 6...Economy device, 7...Bent part "
8... Water pipe t 8b... Straight pipe. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. In a structure in which the wall surface constituting the flue is composed of water pipes and a group of heat transfer tubes such as a superheater and a coal saver are arranged in the flue, the rear wall that partitions the furnace and the flue On the other hand, one or more bent portions are formed that bend toward the furnace side, and one header such as the superheater, economizer, etc. supported by the boiler frame is arranged at one or more bent portions, A water tube boiler, characterized in that the water wall is reinforced by: 2. The device according to claim 1, wherein the bent portion is formed by bending a part of the water wall pipe, and the remaining straight pipe is configured to prevent a header placed in the bent portion from falling off. Water tube boiler.