JP6542060B2 - Heat exchanger tube block exchange method - Google Patents

Description

  The present invention relates to a heat exchanger tube block replacement method for a heat exchanger installed in a flue of a boiler.

  In a coal-fired boiler in which coal is burned as fuel, the molten ash produced by the combustion of coal becomes solid ash (fly ash) in the region where the temperature of the combustion exhaust gas is reduced due to heat exchange with the boiler feed water Flow through the flues. The solid ash may collide with the heat transfer tubes of a heat exchanger such as a superheater or economizer installed in the flue to cause the surface of the heat transfer tubes to wear. In addition, ash may be deposited between the plurality of heat transfer tubes, which may reduce the performance of the heat exchanger.

  For this reason, when a predetermined operation time has elapsed, the heat exchanger is either replaced entirely or, as disclosed in Patent Document 1, the heat transfer tube in which wear or corrosion has progressed is replaced in block (panel) units. It is done. According to the replacement method of Patent Document 1, a frame material is welded and attached as a temporary installation to the side frame of the horizontally installed heat transfer tube block to be replaced, and this portion is jacked up to take the heat transfer tube block out. It has become. According to this method, since the heat transfer pipe can be replaced in the minimum unit, the replacement cost can be reduced and the replacement work period can be shortened.

Unexamined-Japanese-Patent No. 2012-241964

  However, in the case of a plurality of suspended heat exchangers in which vertical plate-like heat transfer tube blocks are suspended in the flue of the boiler, each heat transfer tube block is arranged in the air, so When taking out the heat transfer tube block, there was no portion supporting the load, and it was difficult to replace the heat transfer tube block in units of units. For this reason, in the past, the entire heat exchanger had to be replaced, the replacement cost increased, and the replacement period was extended.

  The present invention has been made in view of such circumstances, and in a suspended heat exchanger in which a plurality of heat transfer tube blocks are suspended adjacent to each other, the heat transfer tube blocks can be individually replaced. An object of the present invention is to provide a heat exchanger tube block replacement method for an exchanger.

  In order to solve the above-mentioned subject, the present invention adopts the following means.

  That is, in the heat exchanger tube block replacement method of a heat exchanger according to the present invention, a specific heat exchanger tube block in a heat exchanger configured by suspending a plurality of heat transfer tube blocks horizontally in a row in a boiler A method of exchanging, wherein vertical lower portions of the heat transfer tube blocks adjacent to both sides in the horizontal direction of the heat transfer tube block to be replaced are connected, and the vertical downward direction of the heat transfer tube block to be replaced is the exchange object A connecting member erecting step for establishing a horizontal connecting member with a gap between the heat transfer pipe block and the suspension part supporting the heat transfer pipe block to be replaced, and the heat transfer pipe to be replaced A separating step of supporting the block on the connecting member; and the heat transfer pipe block to be replaced supported by the connecting member formed on the wall of the boiler Characterized in that from the mouth and a carry-out step of carrying out to the outside of the boiler.

  According to the above replacement method, the weight of the heat transfer tube block to be replaced can be carried by the heat transfer tube block adjacent to the both sides through the connecting member. At the time of this replacement work, since the boiler feed water in the heat exchanger is drained, the weight of the heat transfer pipe block to be replaced is lighter than when the boiler feed water is filled. Therefore, the load does not exceed the allowable strength of the supporting portion of the heat transfer tube block adjacent to both sides.

  Then, in this state, the heat transfer tube block to be replaced is carried out from the opening formed in the wall portion of the boiler to the outside. Therefore, in a suspended heat exchanger in which a plurality of heat transfer tube blocks are suspended adjacently, each heat transfer tube block can be replaced individually, thereby reducing the heat transfer tube replacement cost and shortening the construction period. can do.

  In the above method, in the connecting member installation step, a vertical connecting member is attached to the lower portion in the vertical direction of each heat transfer tube block adjacent to both sides in the horizontal direction of the heat transfer tube block to be replaced The connection members may be assembled and bridged by connecting them with a horizontal connection member extending in the horizontal direction.

  As described above, by assembling and connecting the connecting members, a rigid connecting member can be easily installed even in a narrow boiler in which a plurality of heat transfer tube blocks are installed in close proximity.

  In the above method, a support frame temporary mounting step for temporarily installing a support frame projecting horizontally from the wall of the boiler toward the outside of the boiler, and a horizontal direction from the vertical upper surface of the connecting member to the vertical upper surface of the support frame A track member installation step for installing a track member extending to the track member, and in the unloading step, the heat transfer pipe block to be replaced is mounted on a carriage traveling along the track member, and the carriage together You may make it drive | work on a track member and carry out to the exterior of the said boiler.

  According to the above replacement method, in the unloading step, the heat transfer tube block to be replaced can be made to travel on the track member by the carriage, and can be smoothly unloaded out of the boiler.

  In the above method, in the separation step, a jack is installed between the heat transfer pipe block to be replaced and the connection member, and the heat transfer pipe block to be replaced is supported by the jack, and the heat transfer pipe to be replaced The lifting portion supporting the weight of the block is separated, the carriage is inserted between the heat transfer tube block to be replaced and the track member, and the support by the jack is released to remove the heat transfer tube to be replaced The block may be placed on the carriage.

  According to the above replacement method, the heat transfer tube block to be replaced can be smoothly placed on the carriage in the separation step.

  In the above method, in the unloading step, a crane for suspending the heat transfer pipe block to be replaced is installed outside the boiler, and the crane is transferred out of the heat transfer pipe block to be replaced. The heat transfer tube block may be unloaded while being suspended.

  According to the above replacement method, when the heat transfer tube block to be replaced is carried out to the outside of the boiler, the heat transfer tube block to be replaced can be prevented from falling sideways, and it can be carried out safely and smoothly.

  As described above, according to the heat transfer tube block replacement method according to the present invention, in the suspension type heat exchanger in which a plurality of heat transfer tube blocks are suspended adjacent to each other, the heat transfer tube blocks to be replaced are individually selected. It is possible to replace the heat transfer tube to be replaced and to reduce the replacement cost of the heat transfer tube and to shorten the construction period.

It is a front view which shows an example of the heat exchanger which can apply this invention. It is a top view of the heat exchanger by II arrow of FIG. It is a side view of the heat exchanger by III arrow of FIG. It is a figure which shows the state in which the opening part, the connection member, the support frame, and the track member were provided. It is a figure which shows the state in which the heat exchanger tube block of replacement | exchange object was jacked up. It is a figure which shows the state in which the trolley | bogie was inserted between the heat exchanger tube block of replacement | exchange object, and a track member. It is a figure which shows the state from which the jack was removed. It is a figure which shows the state from which the heat exchanger tube block of exchange object was carried out. It is the top view by IX arrow of FIG. It is a side view by X arrow of FIG. It is a flowchart which shows the flow of the exchange method of a heat exchanger tube block.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 to 3 are a front view, a plan view, and a side view showing an example of a heat exchanger to which the present invention can be applied. The heat exchanger 1 is configured by suspending a plurality of heat transfer tube blocks 3 in the horizontal direction inside the wall portion 2 of the boiler. Each heat transfer tube block 3 has a known configuration in which a plurality of heat transfer tube panels 5 in which the heat transfer tubes are arranged in a serpentine manner and in a planar shape are stacked. That is, in FIG. 1, the vertically disposed heat transfer tube panels 5 are stacked, for example, in a set of five, and the heat transfer tubes are not in close contact with each other by the pair of left and right plate-like side support plates 6 The two sides are held together so as to have a predetermined interval. Furthermore, each side support plate 6 is formed into a block shape by being held at the upper and lower ends by the upper support plate 7 and the lower support plate 8 extending in the vertical vertical direction, respectively, to form the heat transfer tube block 3 .

  Such heat transfer tube block 3 is suspended from an upper beam (not shown) by a plurality of suspension rods 10 (hanging parts) shown in FIG. Thereby, the combustion exhaust gas passing through the inside of the boiler exchanges heat with the boiler feed water flowing inside the plurality of heat transfer pipe panels 5 constituting the heat transfer pipe block 3, and the boiler feed water is warmed.

  Furthermore, as shown in FIG. 3, the upper heat transfer pipe block 3 suspends the lower heat transfer pipe block 3 by the suspension rods 11, and these are vertically connected in a plurality of stages in the vertical direction. In the present embodiment, the heat transfer pipe panels 5 of the upper and lower heat transfer pipe blocks 3 are connected via the connection pipe 13 (see FIG. 1), but the structure is not necessarily connected via the connection pipe 13 For example, upper and lower heat transfer pipe panels 5 may be directly connected by means such as welding. Further, the heat transfer pipe panels 5 of the upper and lower heat transfer pipe blocks 3 may be formed as an integral body without the joint portion.

  When any of the plurality of heat transfer tube blocks 3 configured as described above needs to be replaced, it can be easily replaced by the replacement method according to the present invention. The exchange method according to the present invention comprises the steps S1 to S10 shown in FIG. Each step will be described below in order. In the following description and FIGS. 4 to 10, the code of the heat transfer tube block 3 to be replaced is “3A” to distinguish it from the heat transfer tube block 3 not to be replaced.

  First, as shown in FIGS. 4 and 9, an opening 2a for replacement work corresponding to the position of the heat transfer tube block 3A to be replaced is formed in the wall 2 of the boiler (opening forming step S1). The shape and size of the opening 2a may be the minimum necessary for the heat transfer tube block 3A to be replaced to pass. For example, the heat transfer pipe (water wall) of the wall 2 of the boiler is cut out by gas melting, plasma cutting, cutting with a metal circular saw or the like to form the opening 2a.

  Next, the lower support plate 8 of the heat transfer tube block 3A to be replaced and the upper support plate 7 of the heat transfer tube block 3 located below the heat transfer tube block 3A to be replaced shown in FIG. The hanging rod 11 is separated (the hanging rod 11 directly below the heat transfer tube block 3A to be replaced shown in FIG. 3 is removed in FIG. 10).

  Thereafter, as shown in FIG. 4 and FIG. 10, a connecting member for connecting the lower support plates 8 of the two heat transfer tube blocks 3 which are not to be replaced, which are adjacent to both sides in the horizontal direction of the heat transfer tube block 3A to be replaced. 15 are set up (coupling member setting step S2).

  The connection member 15 is attached to the vertical direction lower part of the heat transfer tube block 3 adjacent to both sides in the horizontal direction of the heat transfer tube block 3A to be replaced, and extends vertically downward, and the lower end of these vertical connection members 15a. And a horizontal connecting member 15b extending in the horizontal direction. The transverse connection member 15b has, for example, a channel cross-sectional shape that is concave in the horizontal direction, but may have another cross-sectional shape.

  In the connecting member installation step S2, the vertical connecting members 15a are attached to the vertical lower portions of the two heat transfer pipe blocks 3 adjacent to the heat transfer pipe block 3A, and the lower ends of the vertical connecting members 15a are connected by the horizontal connecting member 15b. Thus, the connecting member 15 is assembled and constructed.

  The lateral connection member 15b of the connection member 15 extends horizontally below the heat transfer tube block 3A to be replaced, with a predetermined distance from the heat transfer tube block 3A. That is, the lateral connection member 15b is located between the lower support plate 8 of the heat transfer tube block 3A to be replaced and the upper support plate 7 of the heat transfer tube block 3 located vertically below. As shown in FIG. 4, two such connecting members 15 are provided to pass below the two lower support plates 8 of the heat transfer tube block 3A.

  Next, as shown in FIG. 4, a support frame 16 that protrudes horizontally from the inside to the outside of the boiler is temporarily provided on the outer surface of the boiler wall 2 (support frame temporary installation step S3). The shape of the support frame 16 is not particularly limited, but may be joined to a part of the steel frame structure of the boiler (not shown) as long as it has a shape and strength capable of horizontally supporting the track member 17 described later. The upper surface of the support frame 16 is set to the same height as the upper surface of the connecting member 15 (lateral connecting member 15b) attached to the lower portion of the heat transfer tube block 3A to be replaced in the vertical direction.

  Furthermore, the track member 17 is installed on the upper surface of the support frame 16 (track member installation step S4). The track member 17 is, for example, a monorail having an H-shaped or I-shaped cross section, and is disposed at the center of the upper surface of the support frame 16. One end thereof is horizontal from the opening 2 a of the boiler wall 2 toward the inside of the boiler , And mounted on the two lateral connection members 15b. Thus, the track member 17 extends horizontally from above the cross connection member 15 b to above the support frame 16. The track member 17 may be continuous within the above-mentioned range, and may have a joint on the way, and may be formed into a single monorail by assembly.

  Next, as shown in FIGS. 5 and 10, the suspension rod 10 supporting the weight of the heat transfer tube block 3A to be replaced and the connecting pipe 13 connected vertically above the heat transfer tube block 3A to be replaced Are separated, and the weight of the heat transfer tube block 3A to be replaced is supported by the lateral connection member 15b (separating step S5).

  In this separation step S5, first, a jack 20 is installed between the horizontal connection member 15b and the lower support plate 8 of the heat transfer tube block 3A, and the jack 20 supports the weight of the heat transfer tube block 3A, and the weight of the heat transfer tube block 3A Are separated from the connecting rod 13 disposed above the heat transfer tube block 3A.

  As shown in FIG. 10, the jacks 20 are arranged at intervals on both sides of the track member 17 so as to support the lower support plate 8 on the horizontal surface of the horizontal connection member 15b, for example, 4 per 1 heat transfer tube block 3A. Base is used. In this state, the weight of the heat transfer tube block 3A is carried by the heat transfer tube block 3 on the both sides through the jack 20 and the lateral connection member 15b, and is not added to the raceway member 17 or the support frame 16.

  Next, the heat transfer tube block 3A to be replaced whose weight is supported by the connecting member 15 is carried out from the opening 2a formed in the wall 2 of the boiler to the outside (carrying out step S6). At the time of this unloading, as shown in FIG. 6 and FIG. 7, after the carriage 22 is inserted between the lower support plate 8 of the heat transfer tube block 3A to be replaced jacked up by the jack 20 and the track member 17 , Release the support by the jack 20, and place the heat transfer tube block 3A on the carriage 22. Then, the lower support plate 8 of the heat transfer tube block 3A and the carriage 22 are connected by bolts or the like via the L-shaped fitting 23 (see FIGS. 7 and 10) and the like. Thereby, the weight of the heat transfer tube block 3A is added to the track member 17 and the support frame 16 via the carriage 22.

  The carriage 22 can travel along the track member 17 and has a position shift prevention member 22 a that prevents the position shift from the track member 17. The displacement prevention members 22 a are provided on both sides in the horizontal direction of the carriage 22 so as to sandwich the track member 17 from the side surface side. Therefore, the heat transfer tube block 3A to be replaced can travel along the upper surface of the track member 17 together with the carriage 22 and carried out of the opening 2a to the outside of the boiler.

  When transporting the heat transfer pipe block 3A carried out of the boiler to the ground, as shown in FIG. 8, a crane 25 supported by a boiler steel frame or the like vertically above the opening 2a of the boiler wall 2 Alternatively, the heat transfer tube block 3A is suspended and transported by a crane car or the like (not shown).

  Incidentally, even when the heat transfer tube block 3A to be replaced travels along the upper surface of the track member 17 together with the carriage 22 and carried out from the opening 2a to the outside of the boiler, the track member 17 while holding the heat transfer tube block 3A by the crane 25. By traveling the upper side, it is possible to prevent the inclination of the heat transfer tube block 3A and carry it out stably.

  After transporting the heat transfer tube block 3A to be replaced to the ground in this manner, the carriage 22 is connected to the lower support plate 8 of the new heat transfer tube block 3 via the L-shaped bracket 23, and this new heat transfer tube block 3 is transported to the upper surface of the track member 17 from the ground by the crane 25 or a crane car (not shown), and the carriage 22 is allowed to travel on the track member 17 and carried in from the opening 2a to a predetermined position in the boiler (loading step S7) .

  Thereafter, a suspension rod 10 is connected between the new upper support plate 7 of the heat transfer tube block 3 and the upper beam (not shown) or the lower support plate 8 of the upper heat transfer tube block 3 to connect the new heat transfer tube block 3 The heat transfer pipe provided at the side is connected by the connection pipe 13. At that time, by using the connecting pipe 13 for connecting the heat transfer pipes, even if the mounting position of the connecting pipe 13 between the heat transfer pipes changes temporarily before and after the replacement work, the length, shape, etc. of the connecting pipe 13 It is possible to easily install a new heat transfer tube block 3 by adjusting the (a new heat transfer tube block installation step S8).

  Thereafter, various pieces of equipment for loading and unloading, such as the connecting members 15 (15a, 15b), the support frame 16, the track member 17, the carriage 22 and the like are removed (equipment removal step S9). Then, a suspension rod 11 is connected between the lower support plate 8 of the new heat transfer tube block 3 and the upper support plate 7 of the heat transfer tube block 3 provided below the heat transfer tube block 3, and a new The heat transfer pipe block 3 and the heat transfer pipe provided below are connected by the connecting pipe 13. Finally, the opening 2a of the wall 2 of the boiler is closed with a heat transfer pipe (water wall) (opening closing step S10). Thus, the exchange work between the heat transfer tube block 3A to be replaced and the new heat transfer tube block 3 is completed.

  According to the heat transfer tube block 3 replacement method described above, the weight of the heat transfer tube block 3A to be replaced can be carried by the heat transfer tube block 3 located on both sides thereof via the connection member 15. During this replacement work, boiler feed water in the heat exchanger 1 (heat transfer pipe block 3A to be replaced) is drained, and the weight of heat transfer pipe block 3A to be replaced is discharged compared to when the boiler feed water is filled. The weight of the water is reduced. Furthermore, since the atmosphere temperature inside the boiler is also lowered to normal temperature, there is an advantage that the allowable strength of the material becomes higher than the atmosphere at high temperature. As a result, there is no influence that exceeds the allowable strength to the suspension rod 10 that suspends the heat transfer tube block 3 adjacent to the heat transfer tube block 3A to be replaced, and there is no burden.

  Then, in this state, the heat transfer pipe block 3A to be replaced is carried out from the opening 2a formed in the boiler wall 2 to the outside. Therefore, in the suspended heat exchanger 1 in which a plurality of heat transfer tube blocks 3 are suspended adjacently, each heat transfer tube block 3 can be replaced individually, which reduces the replacement cost of the heat transfer tube and works. The period can be shortened.

  For example, it is also possible to attach a temporary supporting member directly to the inner wall surface of the boiler by welding, attach the connecting member 15 thereto, and install the track member 17. However, in this case, the connecting member 15 becomes a large member that connects between the wall surfaces of the boiler, and is long and has a large cross-section for securing strength, resulting in a heavy load.

  On the other hand, since the connecting member 15 in the present embodiment has the connecting member 15 bridged vertically below the heat transfer tube block 3 adjacent to both sides of the heat transfer tube block 3A to be replaced, at a predetermined interval. It is possible to cope with a short and short cross section with a light weight, and replacement work can be easily performed with a very simple facility.

  The connecting members 15 are vertical connecting members 15a attached to the lower portions in the vertical direction of the heat transfer tube blocks 3 adjacent to both sides of the heat transfer tube block 3A to be replaced, and horizontal connecting lower vertical end portions of these vertical connecting members 15a. And a lateral connection member 15b. For this reason, the rigid connection member 15 can be installed quickly and easily even within a narrow boiler in which a plurality of heat transfer tube blocks 3 are installed in close proximity.

  Moreover, the support frame 16 and the track member 17 for carrying out the heat transfer pipe block 3A to be replaced are provided, and the heat transfer pipe block 3A is made to travel along the track member 17 using the carriage 22 and carried out from the opening 2a. Since the heat transfer tube block 3A to be replaced can be smoothly taken out of the boiler.

  Further, when separating the suspension rod 10 supporting the weight of the heat transfer tube block 3A to be replaced, the jack 20 is interposed between the heat transfer tube block 3A to be replaced and the connection member 15 (horizontal connection member 15b). The jack 20 is installed, and the suspension rod 10 supporting the weight of the heat transfer tube block 3A is cut off while supporting the weight of the heat transfer tube block 3A. Then, after the carriage 22 is inserted between the heat transfer tube block 3A and the track member 17, the support by the jack 20 is released and the heat transfer tube block 3A is mounted on the carriage 22. The heat pipe block 3A can be smoothly mounted on the carriage 22.

  Further, since the heat transfer pipe block 3A to be replaced is suspended by the crane 25 provided above the opening 2a of the boiler wall 2 or a crane car not shown, the heat transfer pipe block 3A is outside the boiler It is possible to prevent the heat transfer tube block 3A from being removed safely and smoothly when it is taken out.

  As described above, according to the method for replacing heat transfer tube block 3 according to the present embodiment, each heat transfer tube block in the suspension type heat exchanger 1 in which the plurality of heat transfer tube blocks 3 are suspended adjacently. 3 can be replaced individually, and the heat transfer tube replacement cost can be reduced and the construction period can be shortened.

  If the heat transfer tube block 3A to be replaced is at the side end of the heat exchanger 1 and the non-exchange heat transfer tube block 3 is on only one side, the other side fixes the fixture to the inner wall surface of the boiler. It may be attached by direct welding, or the fixture may be attached through the wall of the boiler. Then, the horizontal connection member 15b is constructed between the vertical connection member 15a attached to the heat transfer tube block 3 adjacent to one side of the heat transfer tube block 3A to be replaced and the fixing tool provided on the wall 2 of the boiler It is possible to assemble the connecting member 15.

  The present invention is not limited to only the configurations of the above-described embodiments, and modifications and improvements can be made as appropriate without departing from the scope of the present invention, and such modifications and improvements can be made. The form is also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 heat exchanger 2 boiler wall 2a opening 3 heat transfer tube block 3A heat transfer tube block 5 to be replaced heat transfer tube panel 6 side support plate 7 upper support plate 8 upper support plate 8 lower support plate 10, 11 suspension rod (hang portion) )
15 connection member 15a vertical connection member 15b horizontal connection member 16 support frame 17 track member 20 jack 22 carriage 25 crane S1 opening formation step S2 connection member installation step S3 support frame temporary installation step S4 track member installation step S5 separation step S6 release step S6

Claims (5)

A method of replacing a specific heat transfer tube block in a heat exchanger configured by suspending a plurality of heat transfer tube blocks horizontally in line inside a boiler, comprising:
The lower portions of the heat transfer tube blocks adjacent to each other in the horizontal direction of the heat transfer tube block to be replaced are connected to each other, and the vertically lower portion of the heat transfer tube block to be replaced is between the heat transfer tube block to be replaced Connecting member erecting step for erecting a horizontally traversing connecting member while having a space between them;
Separating the support portion supporting the heat transfer tube block to be replaced, and allowing the connection member to support the heat transfer tube block to be replaced;
An unloading step of unloading the heat transfer pipe block to be replaced supported by the connecting member from an opening formed in a wall of the boiler to the outside of the boiler;
A heat exchanger tube block replacement method for a heat exchanger, comprising: In the connecting member installation step,
Vertical connection members are attached to the lower portions in the vertical direction of the heat transfer tube blocks adjacent to both sides in the horizontal direction of the heat transfer tube block to be replaced, and vertical lower ends of these vertical connection members are horizontal connection members extending in the horizontal direction The heat exchanger tube block exchange method according to claim 1, wherein the connecting member is assembled and constructed by connecting. A support frame temporary installation step of temporarily installing a support frame projecting horizontally from the wall of the boiler toward the outside of the boiler;
A track member installation step of installing a track member extending in a horizontal direction from the vertical upper surface of the connection member to the vertical upper surface of the support frame,
In the unloading step, the heat transfer tube block to be replaced is placed on a carriage traveling along the track member, and the carriage travels on the track member together with the carriage to carry it out of the boiler. The heat exchanger tube block exchange method of the heat exchanger as described in. In the separation step,
A jack is installed between the heat transfer tube block to be replaced and the connection member, and the jack supports the heat transfer tube block to be replaced by the jack and supports the weight of the heat transfer tube block to be replaced. Separate the hanging part,
Inserting the carriage between the heat transfer tube block to be replaced and the track member;
The heat transfer tube block replacement method according to claim 3, wherein the heat transfer tube block to be replaced is mounted on the carriage by releasing the support by the jack.   In the unloading step, a crane for suspending the heat transfer pipe block to be replaced is installed outside the boiler, and when the heat transfer pipe block to be replaced is unloaded to the outside of the boiler, the heat transfer pipe by the crane The heat exchanger tube block exchange method according to any one of claims 1 to 4, wherein the block is unloaded while being unloaded.

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