JP5862213B2 - How to build a tower boiler - Google Patents

Description

  The present invention relates to a tower boiler construction method.

As a conventional boiler, one in which a portion (contact heat transfer surface) for heating a fluid by convective heat transfer of a high-temperature gas is arranged on the rear side of a furnace (for example, see Patent Document 1). Thus, the heating part arrange | positioned at the rear side of a furnace is generally called the rear part heat-transfer part (rear part).
In contrast, the tower boiler is a conventional boiler in which the contact heat transfer surface, that is, the rear heat transfer portion is arranged on the upper side of the furnace, and the contact heat transfer surface is arranged on the rear side of the furnace. Compared to the above, the installation space is reduced by about 20%, so that it is suitable for the case where the installation place is restricted.

Such a tower boiler has a structure in which a boiler body is suspended and supported by a boiler frame formed between columns via a suspension member.
In the construction of the tower boiler, when the boiler main body is constructed, the rear transmission section (rear heat transfer section) is particularly attached to a high position of the boiler main body, so that the construction is difficult. That is, in the construction of the rear transmission section, usually, the heat transfer tubes constituting the rear transmission section are previously bent into a predetermined shape at the factory, and these heat transfer tubes are carried into the site. And while assembling these heat exchanger tubes in the structure of a rear transmission part, it is assembled | attached in the structure of a boiler main body.

However, assembly of the heat transfer tubes, etc. is a work in a high place and a narrow place, so there is a problem in workability and safety.
Therefore, it is possible to assemble the heat transfer tube into the structure of the rear transmission part at a place other than the construction site such as a factory to make the rear transmission element, and bring this rear transmission element into the construction site and assemble it into the structure of the boiler body. (See, for example, Patent Document 2).

However, each element constituting the rear transmission section is assembled in the boiler body by, for example, arranging a large number of heat transfer tubes independently in a predetermined state without being connected to each other, and finally being fixed to a hanger tube or the like. It is done. Therefore, the assembly of the large number of heat transfer tubes in advance and making the rear transmission element into a unit is that after the assembly of the unit (rear transmission element) into the boiler body is completed, the individual heat transfer tubes are again independent. This is very difficult in design.
Further, even if the rear transmission element is unitized, the rear transmission element in the assembled unit becomes considerably large, so that it is difficult to transport the truck from the factory or the like to the construction site.

Therefore, conventionally, a method of assembling the rear transmission element at a place other than the construction site (unitized) and transporting it to the site cannot be taken, and the heat transfer tube is bent into a shape within the range where it can be placed on the truck. It is transported by truck in the form of open pipes and carried to the site.
That is, the lower part of the boiler body is left open, the heat transfer tubes carried in this empty space are assembled into the structure of the rear transmission section (rear transmission section element), and then the assembled structure (rear transmission section element) is assembled. It is lifted up to the boiler body mounting position and assembled in the structure of the boiler body.

JP 2006-162137 A JP 2002-115804 A

By the way, a large number of heat transfer tubes for forming the rear transmission portion are carried into the construction site by truck transportation in a form bent to the shape of the range on the truck as described above. At that time, because of the restriction due to the bent special shape of the heat transfer tube, the heat transfer tube is laid side by side and stacked in order to increase transport efficiency, and unloaded at the site as it is.
Therefore, when assembling the heat transfer tubes in the boiler body, the heat transfer tubes in the state of being laid down are stacked one by one and connected in order to assemble the structure of the rear transfer unit (rear transfer unit element) It must be a very inefficient process. For this reason, this process is a cause of impairing the shortening of the work period, and the safety of work is also impaired.

  The present invention has been made in view of the above circumstances, and the object of the present invention is to enable more efficient construction of a rear transmission section formed by a large number of heat transfer tubes, thereby shortening the entire construction period. An object of the present invention is to provide a method for constructing a tower boiler with improved work safety.

The tower boiler construction method of the present invention is a tower boiler construction method having a boiler body.
A step of arranging a plurality of heat transfer tubes constituting the rear transfer section of the tower boiler in parallel in a form as a rear transfer section assembled to the boiler body by a temporary fixing tool at a place other than the construction site of the tower boiler,
Holding the heat transfer tubes arranged in parallel in that state, transferring them to the construction site, and carrying them under the boiler body under construction;
A step of assembling the carried heat transfer tube to a lower portion of a boiler body under construction.

  Moreover, in the construction method of the tower boiler, in the process of assembling the carried heat transfer tube to the lower part of the boiler body under construction, the heat transfer tube is arranged in parallel in a form as a rear transmission portion with the temporary fixing tool. Preferably, after the heat transfer tube is assembled to the lower part of the boiler body, the temporary fixing tool is removed.

  According to the tower boiler construction method of the present invention, a plurality of heat transfer tubes are arranged in parallel in a form as a rear transmission portion assembled to the boiler main body at a place other than the construction site, and the parallel arranged heat transfer tubes are constructed at the construction site. Since the heat transfer tube that was carried in was assembled to the lower part of the boiler body under construction, for example, a heat transfer tube that had been laid down and stacked was built at the construction site. It is not necessary to start up the pipes one by one, and it is possible to assemble the loaded heat transfer tubes in the lower part of the boiler body as they are in a parallel arrangement, thereby improving work efficiency and improving work difficulty. The Therefore, the overall construction period can be shortened and the safety of work can be improved.

It is a sectional side view of an example of the tower boiler which concerns on this invention. It is an AA arrow directional view of the tower boiler shown in FIG. It is a schematic block diagram of the heat exchanger tube panel comprised by a heat exchanger tube, and a rear transmission part element. (A)-(c) is process drawing for demonstrating one Embodiment of the construction method of this invention. It is explanatory drawing of the rear transmission part element formed by arrange | positioning a heat exchanger tube in parallel, (a) is a side view, (b) is a principal part front view.

Hereinafter, an embodiment of a tower boiler construction method of the present invention will be described in detail with reference to the drawings.
First, an example of a tower boiler constructed by the tower boiler construction method of the present invention will be described with reference to FIGS. 1 is a side sectional view of an example of a tower boiler, and FIG. 2 is a view taken along the line AA of the tower boiler shown in FIG.

  As shown in FIGS. 1 and 2, the tower boiler has a rectangular horizontal cross-sectional shape due to the front and rear furnace walls 1 and 2 (see FIG. 1) and the left and right furnace walls 3 and 4 (see FIG. 2). A formed boiler body 7 is provided. The boiler body 7 is formed to extend upward and is provided with a ceiling wall 6 at its upper end, and is supported by a suspension member 5 from a steel frame 8. The furnace walls 1 and 2 on the front and rear sides and the furnace walls 3 and 4 on the left and right sides are formed by furnace wall panels formed by connecting parallel furnace wall tubes 9 extending in the vertical direction with fins (not shown). Has been.

A plurality of burners 11 are provided at lower positions of the furnace walls 1 and 2 on the front and rear sides of the boiler body 7, and an exhaust gas outlet 12 is provided at the rear upper end of the boiler body 7. An upper end portion of the flue 13 communicates with the exhaust gas outlet 12, and the flue 13 is disposed extending downward from the exhaust gas outlet 12 side.
Further, a heat exchanging device 14 serving as a rear transmission portion (rear heat transfer portion) in the present invention is installed between the intermediate portion in the vertical direction in the boiler body 7 and the exhaust gas outlet 12. Further, a casing 15 is provided above the boiler body 7 from the middle in the vertical direction so as to surround the outside of the front and rear furnace walls 1 and 2 and the ceiling wall 6. A heat insulating material 16 is provided on the outer periphery of the casing 15 and the lower outer periphery of the boiler body 7.

The heat exchanging device (rear transmission portion) 14 is provided with a economizer 17 at an upper position (low temperature portion side) close to the exhaust gas outlet 12. Below the economizer 17, a low temperature side reheater 18, a low temperature side superheater 19, a high temperature side reheater 20, a high temperature side superheater 21, and a hanger tube superheater 22 are sequentially arranged. .
The economizer 17, the low temperature side reheater 18, the low temperature side superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21 each have a width in the front-rear direction inside the boiler body 7 as shown in FIG. It is comprised by the panel-shaped heat exchanger tube 23 extended over the whole. The panel-shaped heat transfer tubes 23 are arranged in a state in which a large number of the heat exchanger tubes 23 in the boiler body 7 in FIG.

  As shown in FIG. 3, the heat transfer tube 23 is formed by bending a plurality of places at a factory so as to have a predetermined S-shape designed in advance (inverse S-shape in FIG. 3). Further, the heat transfer tubes 23 are bent so as to have different S-shapes, and are arranged on the same plane, so that they are configured in a panel shape as described above. That is, the plurality of different S-shaped heat transfer tubes 23 are arranged on the same plane at a predetermined interval to form a heat transfer tube panel 23A.

  Further, the heat transfer tube panel 23A formed in this way is arranged so that the plane formed by the heat transfer tube panel 23A stands in the vertical direction, and the heat transfer tube panels 23A are arranged with a predetermined interval between each other. A plurality of the economizers 17, the low-temperature side reheater 18, the low-temperature side superheater 19, the high-temperature side reheater 20, and the high-temperature side superheater 21 are formed by being arranged in parallel in the horizontal direction. ing. That is, the economizer 17, the low-temperature reheater 18, the low-temperature superheater 19, the high-temperature reheater 20, and the high-temperature superheater 21 that constitute the heat exchange device (rear transmission section) 14 include a plurality of transmissions. The heat transfer tube panel 23 </ b> A composed of the heat tubes 23 is formed in a predetermined form set in advance.

  Here, the economizer 17, the low temperature side reheater 18, the low temperature side superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21 are one of the rear transmission parts (heat exchanger 14) in the present invention. It is the form which comprises a part, ie, a back transmission element. Accordingly, in the present invention, for example, the economizer 17, the low temperature side reheater 18, the low temperature side is provided by the rear transmission element 23B in which a plurality of heat transfer tube panels 23A as shown in FIG. 3 are arranged in parallel in the horizontal direction. The superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21 are formed.

  The hanger tube superheater 22 is formed by a number of hanger tubes 25 extending downward from a header 24 provided at the upper end. That is, the hanger tube superheater 22 is formed by bending the lower end of the hanger tube 25 in the lateral direction. This hanger tube superheater 22 is also similar to the economizer 17, the low temperature side reheater 18, the low temperature side superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21, as shown in FIG. A plurality of heat transfer tube panels 23A are formed by a rear transfer element 23B that is arranged in parallel in the horizontal direction. That is, the hanger tube 25 is also a heat transfer tube. Therefore, the hanger tube superheater 22 formed by a large number of hanger tubes 25 is also formed by a rear transmission element 23B composed of a large number of heat transfer tubes (hanger tubes 25). Become.

  Further, the hanger tube 25 suspends and supports the heat transfer tubes 23 of the economizer 17, the low temperature side reheater 18, the low temperature side superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21. It is like that. With this configuration, the heat transfer tubes 23 are arranged in an independent state without being connected to each other in the single rear transmission element 23B, and their positions are fixed by the hanger tube 25. Yes. Further, between the rear transmission element 23B, for example, between the rear transmission elements 23B in which the flow paths are continuous with each other, the corresponding heat transfer tubes 23 are connected to each other by welding or the like via other connecting pipes (not shown). ing. If necessary, each rear transmission element 23B (heat transfer tube 23) may be supplementarily fixed to the furnace walls 1 to 4 by a fixing member other than the hanger tube 25.

As shown in FIG. 1, a steam / water separator 28 made of a drum or a separator is connected to the upper ends of the furnace wall tubes 9 of the furnace walls 1, 2, 3, 4 of the boiler body 7. Thus, the heated water heated in the furnace wall tube 9 is separated into water and steam by the steam / water separator 28, and the water is returned to the furnace wall tube 9 of the boiler body 7 again. On the other hand, the steam separated by the steam separator 28 is guided to the header 24 of the hanger tube 25.
In the present example, as shown by a broken line in FIG. 1, the boiler body 7 is provided with gas flow rate adjusting dampers 32 and 33 above the heat exchange device 14, that is, above the economizer 17.

  In the boiler body 7 having such a configuration, the water supply 26 supplied from below is first supplied to the economizer 17. Then, after being heated by the high-temperature exhaust gas 27 generated by the combustion of the burner 11, the feed water 26 is supplied to the lower end of the boiler body 7. Then, the furnace walls 1 and 2 on the front and rear sides of the boiler body 7 and the furnace wall pipes 9 on the left and right furnace walls 3 and 4 are raised while being heated, and are supplied to the steam-water separator 28 on the upper side. And separated into steam. The separated water is returned to the furnace wall tube 9 of the boiler body 7 again.

On the other hand, the steam separated by the steam separator 28 is supplied from the header 24 to the hanger tube 25, descends inside, is led to the hanger tube superheater 22, is overheated, and then enters the low temperature side superheater 19. Then, it is led to the high temperature side superheater 21 to be superheated, and is supplied to the high pressure steam turbine 29 as high temperature high pressure steam.
The steam emitted from the high-pressure steam turbine 29 is supplied to the low-temperature reheater 18 and reheated, and then led to the high-temperature reheater 20 to be further heated, and then the intermediate-pressure or low-pressure steam turbine. 30.

Next, as an embodiment of the present invention, a tower boiler construction method including the boiler body 7 having the above-described configuration will be described.
In this embodiment, first, four main pillars of a tower boiler are constructed, and a boiler frame is formed between these main pillars. In FIGS. 1 and 2, the boiler frame is shown as a steel frame 8.

Next, as shown in FIG. 4A, a ceiling girder (not shown) connecting them to the upper ends of the main pillars 40 is arranged, and a girder 41 is arranged between the ceiling girder, A jack 42 is installed and fixed to the girder 41.
Next, the components of the boiler body 7 are attached to the suspension member 43 such as a wire rope attached to the jack 42 in order from the top while being sequentially lifted. An appropriate balance (not shown) may be attached to the suspension member 43, and each component of the boiler body 7 may be attached to the balance. Moreover, you may use the girder 41 finally arrange | positioned between the said ceiling girder as a balance.

  In FIG. 4 (a), the gas flow rate adjusting dampers 32 and 33 are lifted, and further, elements constituting a part of the rear transmission portion (heat exchange device 14), that is, the economizer 17, the low-temperature side reheater. 18, each element which comprises the low temperature side superheater 19, etc., ie, the rear transmission elements 17E-21E, are suspended sequentially according to the arrangement | positioning order shown in FIG. Moreover, in this embodiment, in order to assemble the hanger tube superheater 22 under the high temperature side superheater 21, the rear transmission element 22E for forming the hanger tube superheater 22 is formed.

  That is, as shown in FIG. 3, a heat transfer tube panel 23A is formed from a plurality of heat transfer tubes 23 (hanger tubes 25), and a plurality of heat transfer tube panels 23A are arranged in parallel to form a hanger tube superheater 22. Then, the rear transmission element 23B (22E) is formed. The rear transmission element 23B is formed at a place other than the tower boiler construction site, for example, at a factory. Further, when the construction site of the tower boiler is far from the factory, the rear transmission element 23B may be formed on a large site close to the construction site of the tower boiler.

  At that time, the rear transmission element 23B to be formed is arranged in parallel in a form in which each heat transfer tube 23 (each heat transfer tube panel 23A) is assembled to the boiler body 7 by a temporary fixing tool. That is, the rear transmission element 23B (22E) serving as the hanger tube superheater 22 is arranged in parallel in a form that is assembled to the high temperature side superheater 22 arranged thereon.

  Specifically, as shown in FIGS. 5 (a) and 5 (b), a bottom beam 45 made of steel or the like, as shown in FIG. 5 (b), a sandwiching column 46 and a sandwiching column for sandwiching the heat transfer tube panel 23A individually. A temporary fixture 44 including a beam 47, a suspension member 48, and the like provided on 46 is arranged in parallel in a form to be assembled to the high temperature side superheater 22.

  That is, each heat transfer tube panel 23A is arranged upright on the bottom rail 45, and as shown in FIG. 5B, the heat transfer tube panel 23A is arranged between the pair of sandwiching columns 46, and both sides thereof are sandwiched by the sandwiching columns 46. The heat transfer tube panel 23 </ b> A is clamped in a state of being fixed between the pair of clamping columns 46 by, for example, pressing and bolting between the pair of clamping columns 46 in that state. A plurality of pairs of the sandwiching columns 46 are arranged with respect to one heat transfer tube panel 23A. Further, a plurality of heat transfer tube panels 23 </ b> A arranged in parallel on the bottom bar 45 are provided, respectively. Further, the interval between adjacent pairs is adjusted to correspond to the interval between the heat transfer tube panels 23 </ b> A in the hanger tube superheater 22.

  Therefore, by arranging the heat transfer tube panels 23A in an upright state between each pair of the sandwiching columns 46, these heat transfer tube panels 23A are configured as a rear transmission portion assembled to the boiler body 7, that is, the rear transmission portion element 23B. (22E) is arranged in parallel. As shown in FIG. 5A, the heat transfer tube panel 23 </ b> A has both end portions of the heat transfer tube 23 temporarily fixed by temporary fixing materials 29.

  The rear transmission element 23B (22E) made up of a large number of heat transfer tubes 23 (hanger tubes 25) arranged in parallel in this way is kept on the state of being arranged in parallel and is stacked on the truck bed by the suspension member 48. It is done. And it is transported (transferred) to the construction site of the tower boiler. At the construction site, the boiler main body 7 under construction is lifted, and therefore the rear transmission element 23B (22E) is carried downward as shown in FIG. 4 (a). The rear transmission element 22E (23B) may be carried directly under the boiler body 7 by a truck when the site is large, and when the site is narrow, the temporary fixing tool may be used after being lowered from the truck. The rear transmission element 22E (23B) fixed in the state of being arranged in parallel at 44 may be transferred (carried in) below the boiler body 7 by a crane or the like.

  Next, the rear transmission element 22E (23B) composed of the carried heat transfer tube 23 (hanger tube 25) is aligned (centered) with the rear transmission element 21E of the high-temperature side superheater 21 located immediately above. That is, alignment is performed so that corresponding members (for example, hanger tubes 25) of the elements 21E and 22E overlap each other in plan view.

  Next, the rear transmission element 22E (23B) is pushed up by a jack or the like (not shown), and the rear transmission element 22E (23B) carried in as shown in FIG. Level matching with the element 21E is performed. That is, each member of the rear transmission element 21E of the high-temperature side superheater 21 and each member (hanger tube 25) of the rear transmission element 22E (23B) carried in are connected in correspondence with each other. Adjust levels as possible. Here, each element (rear transmission element 17E-21E) etc. of the boiler main body 7 up to the rear transmission element 21E of the high-temperature side superheater 21 that has been lifted earlier is slightly lowered by the jack 42 and carried in. You may make it perform level alignment between the rear transmission element 22E (23B) and the rear transmission element 21E of the high temperature side superheater 21 suspended.

Thereafter, the rear transmission element 21E and the rear transmission element 23B (22E) are connected via a hanger tube 25 arranged in the vertical direction, and members corresponding to each other between these elements are welded or the like. Connect by.
And when the connection between such elements is complete | finished, the temporary fixing tool 44 is removed from the rear transmission element 23B (22E).
Thereafter, as shown in FIG. 4 (c), each element of the boiler body 7 (rear transmission elements 17E to 22E) and the like are lifted by the jack 42, and the assembly (assembly) of the remaining part of the boiler body 7 is performed in the same manner as before. Do it.

  In such a tower boiler construction method, a plurality of heat transfer tubes 23 (hanger tubes 25) are arranged in parallel in a form as a rear transmission portion that is assembled to the boiler body 7 at a place other than the construction site. The element 22E (23B) is used, and then the transmission element 22E (23B) is transferred to the construction site and carried under the boiler body 7 under construction. Therefore, the plurality of heat transfer tubes 23 are arranged in parallel in the above configuration. The process to be performed can be performed in a wide place equipped with facilities such as a factory, and therefore, work can be performed efficiently and safely.

In addition, since the rear transmission element 23B (22E) composed of a large number of the heat transfer tubes 23 that have been carried in is simply positioned and then assembled as it is to the lower part of the boiler body 7 that is being constructed, it is laid down as before. It is not necessary to start up the heat transfer tubes in a stacked state one by one at the construction site, and after loading, the heat transfer tubes 23 of the heat transfer element 23B (22E) are left in the parallel arrangement state, and the lower part of the boiler body 7 Can be assembled.
Therefore, the work efficiency can be significantly improved as compared with the prior art, and the difficulty of work can be improved. Therefore, the overall construction period can be shortened and the safety of work can be enhanced.

  Moreover, in the process of assembling the rear transmission section element 23B (22E) carried into the lower portion of the boiler body 7 under construction, the heat transfer tubes 23 are arranged in parallel in the form of the rear transmission section with the temporary fixing tool 44. Since each temporary heat transfer tube 23 is assembled to the lower part of the boiler body 7 and the temporary fixing tool 44 is removed, the transfer element 23B ( Since the heat transfer tube 23 on the 22E) side is fixed in a stable state, the work such as welding becomes easier, and the work efficiency is remarkably improved as compared with the conventional case.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.
For example, in the above-described embodiment, the heat transfer tube 23 (hanger tube 25) for forming the hanger tube superheater 22 is assembled to the boiler body 7 to form the hanger tube superheater 22 and the rear transfer element 23B (22E). The rear transmission element 23B (22E) is assembled to the boiler body 7 at the construction site, but if it is a rear transmission section, that is, a component of the heat exchange device 14, the hanger tube superheater Similarly, the economizer 17, the low temperature side reheater 18, the low temperature side superheater 19, the high temperature side reheater 20, and the high temperature side superheater 21 other than 22 are arranged in parallel in the form of the rear transmission element 23B. This may be assembled to the boiler body 7 at the construction site.

DESCRIPTION OF SYMBOLS 7 ... Boiler main body, 14 ... Heat exchange apparatus (rear transmission part), 17 ... Eco-saving device, 18 ... Low temperature side reheater, 19 ... Low temperature side superheater, 20 ... High temperature side reheater, 21 ... High temperature side overheating , 22 ... Hanger tube superheater, 23 ... Heat transfer tube, 23A ... Heat transfer tube panel, 23B ... Rear transmission element, 17E-22E ... Rear transmission element, 44 ... Temporary fixture

Claims (2)

In the construction method of a tower boiler having a boiler body,
A step of arranging a plurality of heat transfer tubes constituting the rear transfer section of the tower boiler in parallel in a form as a rear transfer section assembled to the boiler body by a temporary fixing tool at a place other than the construction site of the tower boiler,
Holding the heat transfer tubes arranged in parallel in that state, transferring them to the construction site, and carrying them under the boiler body under construction;
The process of assembling the carried heat transfer tube to the lower part of the boiler body under construction;
A step of lifting the assembled heat transfer tube,
In the step of assembling the carried heat transfer tube to the lower part of the boiler body under construction, the heat transfer tube is arranged in parallel with the temporary fixing tool in the form of a rear transfer part, and the heat transfer tube is assembled to the lower part of the boiler body. Then, the construction method of the tower boiler characterized by removing the said temporary fixing tool . The tower boiler construction method according to claim 1 , wherein the temporary fixing tool is held in a state of being arranged in parallel by sandwiching the heat transfer tube.

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