JP6817732B2 - How to clean the heat exchanger - Google Patents

Description

The present invention relates to cleaning how the heat exchanger.

As shown in FIG. 10, the heat exchanger 13 installed in the flue or duct of a boiler such as an exhaust heat recovery boiler and exchanging heat with high-temperature gas (exhaust gas) for water supply or steam is arranged in the duct 12 of the boiler. It is composed of a heat transfer tube 14 (tube). In the example shown in FIG. 10, exhaust gas flows in the direction of the arrow from one side (lower side of the paper surface) of the heat exchanger 13 to the other side (upper side of the paper surface) and exchanges heat with the fluid passing through the heat transfer tube 14. .. As shown in FIG. 11, in the heat transfer tube 14, fins 15 may be provided around the outer peripheral surface of the heat transfer tube 14 to increase the heat transfer area and improve the heat exchange efficiency of the heat exchanger 13.

Since it takes a long time to manufacture and install a boiler, for example, 1 to 2 years, a coating film is applied to the outer surface of the heat transfer tube and fins in order to prevent rust from occurring in the steel heat transfer tube. In addition, even during boiler operation, by applying a coating film treatment to the outer surface of the heat transfer tube and fins, the sulfur component and ammonia component cause corrosion on the fins and heat transfer tube due to contact with exhaust gas containing ammonium sulfate (ammonium sulfate). It is also possible to suppress wall thinning.

The coating film applied to the outer surface of the heat transfer tube and fins has a thickness of about several tens of μm, and as a result of being exposed to high-temperature gas during long-term operation of the boiler, the coating film deteriorates and the thermal expansion cycle at the time of starting and stopping, etc. It is known that it peels off. If the peeled coating film has a small size such as powder, it passes between multiple heat transfer tubes and fins and falls due to gravity, or flows to the downstream side of the exhaust gas and is discharged from the chimney, which hinders operation. There are few things. On the other hand, the peeled coating film piece having a size that does not easily pass between the heat transfer tubes and the fins stays in the vicinity between the heat transfer tubes and the fins. It is presumed that such a coating film piece does not pass between the heat transfer tubes during the operation of the boiler, but is sandwiched between the heat transfer tubes or is caught and dances in the space between the heat transfer tubes. Further, as shown in FIG. 11, in some cases, the peeled coating film piece P remains sandwiched between the fins 15 formed on the outer surface of the heat transfer tube 14.

In either case, the peeled coating film piece becomes a resistor for the exhaust gas flow, and a pressure loss occurs in the exhaust gas flow. Further, when the peeled coating film piece affects the contact state between the heat transfer tube and the flow of the exhaust gas, the heat transfer coefficient of the outer surface of the heat transfer tube may be lowered, and the heat transfer performance may be lowered. Therefore, in order to maintain the efficiency of the heat exchanger, it is necessary to remove the peeled coating film piece from the heat exchanger.

Jitsukaisho 61-8977 Japanese Unexamined Patent Publication No. 2011-174661

Conventionally, methods for removing the peeled coating film pieces include chemical cleaning and a method using a jig such as a hammering, a suit blower, and a brush.

In the case of wet cleaning such as a chemical cleaning method using a chemical cleaning solution, when cleaning the heat transfer tube, corrosion occurs on the outer surface of the heat transfer tube in the area where the coating film for preventing corrosion thinning is peeled off. There is a risk of In addition, workability is poor because drying is required to prevent corrosion after chemical cleaning.

In the case of a hammering method using a hammering device, etc., when the hammering device, etc. gives an impact to the tube and vibrates to shake off the peeled coating piece, the impact force generated by the hammering device, etc. is strong. There is a risk of deformation or partial damage to the heat transfer tube and fins. In addition, the effect of removing the peeled coating film pieces is likely to be concentrated near the impacted region, and the peeled coating film pieces are difficult to be removed in other regions. Therefore, it is necessary to move the impacted region with a hammering device or the like. There is a problem that the work becomes complicated. Further, it is difficult to give an impact to the heat transfer tube located deep in the heat exchanger, and there is a problem that the removal area of the coating film piece is easily limited.

Further, as a method of avoiding deformation of the heat transfer tube by the hammering method, for example, a vibration force is applied to a connecting rod or a header connecting a plurality of heat transfer tubes by an electric vibration device (vibrator) or the like. There is also a method of transmitting vibration to a heat transfer tube or fin (for example, Patent Document 1 described above). However, there is a risk that equipment costs will increase due to trial and error in selecting the vibration point, reinforcement for the vibration point, and the need to increase the size of the vibration device or install multiple units. There is.

Furthermore, in the case of the method using a suit blower that injects steam, there is an advantage that the space between the heat transfer tube and the fins can be frequently cleaned during operation, but the effective distance that the peeled coating piece can be frequently removed is the suit blower. It is limited to the range of 1m to 1.5m. Therefore, in a large heat exchanger with a heat transfer tube length of 20 m, it is necessary to install multiple suit blowers, which reduces the heat recovery rate due to the increase in the amount of steam used and each suit. Equipment such as steam pipes that supply steam to the blower will be added, increasing costs.

Furthermore, in the case of the method using a brush as in Patent Document 2, a brush having a cylindrical shape and having a large number of bristles radially planted from the center to the outside is formed between the heat transfer tubes and fins. The brush is inserted and slides between the heat transfer tubes and fins to remove the peeled coating piece. However, especially in the case of a heat transfer tube with fins, it was found that if the bristles of the brush get caught or entangled in the fins, the brush will come off from the jig that fixed the brush, and cleaning cannot be continued. .. Therefore, it is difficult to continuously remove the coating film pieces, and if the detached brush remains in the heat transfer tube group and cannot be recovered, the heat transfer characteristics are hindered like the peeled coating film pieces. May occur.

The present invention was made in view of such circumstances, provide efficient cleaning how the heat exchanger which can remove accumulated foreign matter such as dust between the heat transfer tube and the fins The purpose is to do.

In order to solve the above problems, the heat exchanger cleaning method and the heat transfer tube cleaning tool of the heat exchanger of the present invention employ the following means.
That is, the method for cleaning the heat exchanger according to the present invention is a method for cleaning the heat exchanger using a heat transfer tube cleaning tool having a plate-shaped member long in one direction, and is the heat transfer tube of the heat exchanger or the heat transfer. The step of bringing at least a part of the plate-shaped member into contact with the fins provided on the outer peripheral surface of the heat pipe, and sliding the plate-shaped member with respect to the heat transfer tube or the fins, the heat transfer tube or the said The heat transfer tube or a part of the fin is provided with a step of generating self-excited vibration by a frictional force between the fin and the plate-shaped member.

According to this configuration, the heat transfer tube cleaner has a plate-shaped member that is long in one direction, and at least a part of the plate-shaped member is brought into contact with the heat transfer tube and fins of the heat exchanger. Then, the plate-shaped member is slid with respect to the heat transfer tube and the fin, and the frictional force between the heat transfer tube and the plate-shaped member causes self-excited vibration in at least a part of the heat transfer tube and the fin. As a result, dust accumulated between the heat transfer tubes and fins, and dust such as peeled coating film pieces adhering to the heat transfer tubes and fins vibrates, and dust is removed from the heat transfer tubes and fins.

In the above invention, the plate-shaped member may have a flat plate shape.
According to this configuration, at least a part of the plate surface of the plate-shaped member having a flat plate shape and the edge portions of both side ends can come into contact with the heat transfer tube.

In the above invention, the plate-shaped member may have a corrugated plate shape.
According to this configuration, at least a part of the peaks and valleys of the corrugated plate-shaped member can come into contact with the heat transfer tube. In addition, since the strength of the plate-shaped member in the direction orthogonal to the plate surface is improved by the peaks and valleys, the plate-shaped member can be made thinner than the case where the plate-shaped member has a flat plate shape. The shape member becomes lightweight and workability is improved.

In the above invention, a handle portion that can be gripped by an operator may be formed on one end side of the plate-shaped member.
According to this configuration, when the operator grips the handle portion formed at one end of the plate-shaped member, the workability of sliding the plate-shaped member with respect to the heat transfer tube and the fin is improved. Cleaning work can be easily performed.

In the above invention, the handle portion may have a shape in which at least a part thereof projects in one direction with respect to the plate surface of the plate-shaped member.
According to this configuration, even if the plate-shaped member is removed from the hand, at least a part of the plate-shaped member protrudes in one direction with respect to the plate surface, so that the protruding handle portion By being caught in the heat transfer tube, it is possible to prevent the plate-shaped member from falling and remaining in the heat exchanger.

In the above invention, the plate-shaped member may have at least one opening formed in the plate surface.
According to this configuration, since the plate-shaped member has an opening formed in the plate surface, the plate-shaped member can be lightened and reduced in weight without significantly reducing the strength of the plate-shaped member.

In the above invention, the heat transfer tube cleaning tool is plate-shaped and further includes a receiving plate installed so as to face the plate surface of the plate-shaped member, and the receiving plate is the heat transfer tube or the fin. In the step of generating the self-excited vibration, it may be arranged so as to be located vertically below the plate-shaped member.
According to this configuration, the receiving plate receives dust such as coating film pieces that have been blown off and dropped by the self-excited vibration of the heat transfer tube and fins generated by the plate-shaped member. Further, it is preferable because the fallen dust can be further reduced on the lower heat transfer tube and fins, and the fallen dust can be prevented from accumulating on the lower heat transfer tube and fins. ..

The heat transfer tube cleaner of the heat exchanger according to the present invention is provided with a plate-shaped member long in one direction, and the plate-shaped member is provided with respect to the heat transfer tube of the heat exchanger or the fins provided on the outer peripheral surface of the heat transfer tube. At least a part of the contact, the plate-shaped member slides against the heat transfer tube or the fin, and the frictional force between the heat transfer tube or the fin and the plate-shaped member causes the heat transfer tube or the plate-like member. It is used to generate self-excited vibration in at least a part of the fins.

In the above invention, the cross-sectional shape orthogonal to the longitudinal direction of the plate-shaped member may be at least partially corrugated or uneven.

In the above invention, the plate-shaped member may have at least one opening formed in the plate surface.

According to the present invention, foreign matter such as dust accumulated between heat transfer tubes and fins can be efficiently removed.

It is a front view which shows the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is a vertical cross-sectional view which shows the duct and the heat exchanger of the exhaust heat recovery boiler. It is a vertical cross-sectional view which shows the heat transfer tube of a heat exchanger and the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is a front view which shows the 1st modification of the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the 1st modification of the heat transfer tube of a heat exchanger and the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is a perspective view which shows the 2nd modification of the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is a front view which shows the 2nd modification of the heat transfer tube cleaning tool which concerns on 1st Embodiment of this invention. It is a vertical cross-sectional view which shows the heat transfer tube of a heat exchanger and the heat transfer tube cleaning tool which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the heat transfer tube of a heat exchanger and the heat transfer tube cleaning tool which concerns on 2nd Embodiment of this invention. It is a vertical sectional view which shows the heat exchanger installed in the duct of the exhaust heat recovery boiler. It is a front view which shows the heat transfer tube of a heat exchanger.

[First Embodiment]
Hereinafter, the heat transfer tube cleaning tool 1 according to the first embodiment of the present invention will be described.
As shown in FIG. 2, a heat exchanger 13 is installed inside a duct 12 of an exhaust heat recovery steam generator (HRSG) used in a thermal power plant or the like. The heat exchanger 13 is composed of a plurality of heat transfer tubes 14. Each heat exchanger 13 has a size and a structure that allows an operator to be placed on the upper surface, and the operator can view the heat transfer tube 14 inside the heat exchanger 13 from the upper surface or the lower surface of the heat exchanger 13. Therefore, the heat transfer tube cleaning tool 1 according to the present embodiment can be inserted to perform a cleaning operation for removing dust such as peeled coating pieces existing between the heat transfer tubes 14. Further, fins 15 (see FIG. 11) are provided on the outer peripheral surface of the plurality of heat transfer tubes 14 to increase the heat transfer area and improve the heat exchange efficiency of the heat exchanger 13.

The heat transfer tube cleaning tool 1 according to the present embodiment is a metal plate-shaped member having a long shape in one direction. As shown in FIG. 1, the heat transfer tube cleaning tool 1 has a cleaning unit 2 and a handle unit 3. The cleaning unit 2 is inserted diagonally with respect to the vertical / horizontal arrangement of the heat transfer tubes 14 as shown in FIG. 3 in a narrow space where the gap between the heat transfer tubes 14 and the fins 15 is about several tens of mm. , A portion that at least partially contacts the heat transfer tube 14 and the fins 15. The handle portion 3 is provided on one end side of the cleaning portion 2. For example, an opening 4 is formed in the plate-shaped member so that the operator's hand can easily grasp it, and one end of the heat transfer tube cleaning tool 1 becomes the handle portion 3.

The length of the heat transfer tube cleaning tool 1 in the longitudinal direction is, for example, 1 m to 3 m, and the heat transfer tube cleaning tool 1 has, for example, a linear cross-sectional shape cut in the width direction and a vertical cross-sectional shape cut in the longitudinal direction. It is a flat plate-shaped member. The heat transfer tube cleaning tool 1 has a thickness that can be inserted into a gap between adjacent heat transfer tubes 14 and fins 15. That is, the plate thickness of the heat transfer tube cleaning tool 1 is smaller than the distance of the gap between the adjacent heat transfer tubes 14 and fins 15. When the gap between the outer surfaces of the adjacent heat transfer tubes 14 and fins 15 (between the tips of the fins 15) is about 5 mm to 20 mm, the plate thickness of the heat transfer tube cleaner 1 is about 2 mm to 4 mm.

As shown in FIG. 3, the heat transfer tube cleaning tool 1 is inserted diagonally in the vertical direction between the adjacent heat transfer tubes 14 and fins 15, and is formed on the plate surface or edge of the cleaning portion 2 of the heat transfer tube cleaning tool 1. At least a part of the heat transfer tube 14 and the fin 15 are brought into contact with the outer surface (for example, the tip of the fin). Then, when the heat transfer tube cleaning tool 1 is slid with respect to the heat transfer tube 14 in the directions indicated by the arrows D1 and D2, the heat transfer tube cleaning tool 1 is subjected to the frictional force with the heat transfer tube 14 due to the frictional force with the heat transfer tube 14. Self-excited vibration is generated in at least a part of 14 and fin 15.

The length of the heat transfer tube cleaning tool 1 in the longitudinal direction is such that the heat transfer tube cleaning tool 1 is inserted into the heat exchanger 13 from the upper surface or the lower surface in the vertical direction of the heat exchanger 13 and is located at the center of the heat transfer tube 14. It is a length that can reach the fins 15 and slide with respect to the heat transfer tube 14 and the fins 15. In the present embodiment, the length of the heat transfer tube cleaning tool 1 in the longitudinal direction is, for example, 1 m to 3 m, and the heat transfer tube cleaning tool 1 slides in the direction of arrow D1 with a stroke of about 1 m to 2.5 m while moving for about several seconds each. I'm letting you.

It is desirable that the length of the heat transfer tube cleaning tool 1 in the direction orthogonal to the longitudinal direction, that is, in the lateral direction, is a length that is easy for the cleaning operator to handle. The length of the heat transfer tube cleaning tool 1 in the lateral direction is 150 mm to 300 mm. The heat transfer tube cleaning tool 1 is moved along the longitudinal axis direction of the heat transfer tube 14 in order to change the vibration location.

When performing cleaning work to remove dust such as coating film pieces accumulated between the heat transfer tubes 14 and fins 15, the boiler is in a stopped state and the temperature drops to a temperature at which the operator can enter the boiler. Therefore, the heat transfer tube cleaning tool 1 is operated by the manual force of the operator to carry out the cleaning work. At this time, the coating film pieces are in a state of being deposited on the heat transfer tube 14 and the fins 15.

When the plate surface of the heat transfer tube cleaning tool 1 is brought into contact with the outer surface of the heat transfer tube 14 or the fin 15 (for example, the tip of the fin 15), for example, as shown in FIG. 3, the heat transfer tube cleaning tool 1 is transferred to the fin 15 (transmission). By inserting it into the gaps formed vertically and diagonally between the heat pipes 14), the heat transfer tube cleaner 1 is inserted into the two adjacent heat transfer tubes 14 in the nth stage and the two adjacent heat transfer tubes 14 in the n + 1th stage. A frictional force is generated by contacting the fin 15 (heat transfer tube 14) and sliding the fin 15 (heat transfer tube 14). When the heat transfer tube cleaning tool 1 is brought into contact with the fins 15 (heat transfer tubes 14), at least a part of the plate surface may be brought into contact with the fins 15 (heat transfer tubes 14), or at the edges of both end portions of the plate surface. At least a part of it may be brought into contact with the fin 15 (heat transfer tube 14) and slid. When the edge portions of both end portions are brought into contact with the fins 15 (heat transfer tube 14), the heat transfer tube cleaning tool 1 is tilted with respect to the longitudinal axis direction of the heat transfer tube 14 so that the contact sliding is possible.

Further, as shown in FIGS. 2 and 3, particularly when a plurality of heat transfer tubes 14 are staggered, the heat transfer tube cleaning tool 1 is obliquely oriented with respect to the vertical direction (exhaust gas flow direction) of the heat exchanger 13. To insert. The cleaning work at this time is repeated by appropriately combining and repeating operations including pushing in, pulling back, and rubbing the heat transfer tube cleaning tool 1, thereby generating self-excited vibration in the heat transfer tube 14 and fins 15. The state of occurrence of this self-excited vibration is the magnitude of the sound generated during sliding and the magnitude of the vibration transmitted from the heat transfer tube cleaning tool 1, while adjusting the appropriate moving speed and stroke of the heat transfer tube cleaning tool 1. It is desirable to set. In FIGS. 2 and 3, the push-in direction and the pull-back direction of the heat transfer tube cleaning tool 1 are indicated by arrows D1, and the rubbing direction of the heat transfer tube cleaning tool 1 is indicated by an arrow D2.

Since the generated self-excited vibration propagates in the longitudinal axis direction of the long heat transfer tube 14, vibration is also generated in the non-contact portion other than the contact portion between the heat transfer tube 14 and the fin 15 and the heat transfer tube cleaning tool 1. .. As a result of the vibration generated in the heat transfer tube 14 and the fin 15, the peeled coating film pieces deposited on the heat transfer tube 14 and the fin 15 vibrate, and are wiped off from the heat transfer tube 14 and the fin 15 and fall by gravity. .. In addition, the self-excited vibration generated can peel off the coating film that has not been peeled off but has a reduced adhesive force on the outer surface of the heat transfer tube 14, and can be dropped by gravity.

After the heat transfer tube cleaning tool 1 is appropriately combined with pushing in, pulling back, and rubbing to perform repeated sliding operations a plurality of times, the heat transfer tube 14 is further slid and moved in the longitudinal axis direction in the same manner. The heat transfer tube 14 and the fins 15 are sequentially moved over the entire longitudinal axis direction of the heat transfer tube 14 by repeatedly performing the sliding operation in which the heat tube cleaning tool 1 is pushed in, pulled back, and rubbed as appropriate. It can be vibrated, and the coating piece can be wiped off in all the longitudinal axis directions of the heat transfer tube 14.

The heat transfer tube 14 and fins 15 located deep in the heat exchanger 13 are formed by repeatedly performing the sliding operation by appropriately combining the push-in, pull-back, and rubbing of the heat transfer tube cleaning tool 1 which is long in the longitudinal direction. Also, the heat transfer tube 14 and the fins 15 can be sequentially vibrated, and the coating piece can be wiped off in all the longitudinal axis directions of the heat transfer tube 14 of the heat exchanger 13.

Further, the heat transfer tube 14 and the fin 15 are sequentially vibrated over the entire heat exchanger 13, and the peeled coating piece deposited on the heat transfer tube 14 and the fin 15 is wiped off from the heat transfer tube 14 and the fin 15. After dropping by gravity, the peeled coating piece that has fallen and redeposited may remain. For this reason, compressed air is blown toward the heat transfer tube 14 and fins 15 of the heat exchanger 13 from an air nozzle (not shown) to blow off and remove the peeled coating film pieces that have fallen and redeposited and remained. Is even more preferable. Since the peeled coating pieces are sequentially dropped by gravity, the compressed air is blown by injecting compressed air from the heat transfer tubes 14 and fins 15 on the upper side in the vertical direction to the heat transfer tubes 14 and fins 15 on the lower side in the vertical direction. Is more preferable.

In the above-described embodiment, the method of removing the peeled coating film piece in the case of the heat transfer tube 14 with fins 15 has been described, but the present invention is not limited to this example. That is, it can be similarly applied to a method of cleaning dust in the heat exchanger 13 when the heat transfer tube 14 is not provided with fins.

As described above, the heat transfer tube cleaning tool 1 is a plate-shaped member as shown in FIG. 1, and at least a part of the plate surface or the edge portions on both ends is slid with respect to the heat transfer tube 14, and is pushed and pulled and rubbed. Is repeated. By providing the handle portion 3 on one end side of the heat transfer tube cleaning tool 1 in the elongated direction, the operator can easily perform the cleaning operation using the heat transfer tube cleaning tool 1.

Further, in the above-described embodiment, the case where the heat transfer tube cleaning tool 1 is a flat plate-shaped member having a linear cross section has been described, but the present invention is not limited to this example. For example, as shown in FIG. 4, the cleaning portion 2 of the heat transfer tube cleaning tool 1 is composed of a corrugated plate having a plurality of peaks 5 and valleys 6, and has a corrugated or uneven cross-sectional shape orthogonal to the longitudinal direction. It may be. Since at least a part of the cleaning portion 2 has a corrugated or uneven shape, the heat transfer tube cleaning tool 1 can be made rigid so as to improve the strength in the longitudinal direction orthogonal to the plate surface and not to bend. Further, since the cleaning portion 2 has a rigidity, the plate thickness of the heat transfer tube cleaning tool 1 can be reduced as compared with the case where the cleaning portion 2 has a flat plate shape, and the heat transfer tube cleaning tool 1 can be made lighter to improve workability. ..

Further, in the case of this modification, as shown in FIG. 5, at least a part of the corrugated peaks 5 or valleys 6 provided is the heat transfer tube 14 or the fins 15 (in the case of the heat transfer tube 14 with fins 15). , The tip of the fin 15), so the contact area is dispersed and the contact area is larger than when the heat transfer tube cleaner 1 is a flat plate and at least a part of the plate surface is in contact with the heat transfer tube 14. It becomes smaller. As a result, the frictional force is reduced in the repeated work of pushing and pulling and rubbing the heat transfer tube cleaning tool 1, and the burden on the operator can be reduced. Further, as compared with the case of a flat plate, the contact points between the heat transfer tube cleaning tool 1 and the outer surface (tip portion of the fin) of the heat transfer tube 14 are dispersed and increased, so that the efficiency with respect to the heat transfer tube 14 and the fin 15 is increased. Self-excited vibration can be generated well.

The thickness of the heat transfer tube cleaning tool 1 (difference in height between the peaks 5 and the valleys 6) is such that the gap between the outer surfaces of the adjacent heat transfer tubes 14 and fins 15 (between the tips of the fins 15) is, for example, 5 mm. When it is about 20 mm, it is less than 5 mm. Further, in this modification, the pitch between the peaks 5 or 6 of the corrugated shape is, for example, 30 mm to 100 mm. As a result, when the peeled coating film piece is wiped off by vibration, it becomes difficult to be caught between the fin 15 of the heat transfer tube 14 and the plate surface of the heat transfer tube cleaning tool 1. Further, the corrugated peaks 5 or valleys 6 may not be present on the entire plate surface of the heat transfer tube cleaning tool 1. For example, the corrugated peaks 5 or valleys 6 may be located only on both ends in a cross section orthogonal to the longitudinal direction of the heat transfer tube cleaner 1, or may be transverse to the heat transfer tube cleaner 1 in the longitudinal direction. It may be located only in the central portion of the surface, or the pitch between the peaks 5 or 6 of the corrugated shape may be non-uniform, and the same effect can be obtained.

It is more preferable that the material of the heat transfer tube cleaning tool 1 is, for example, aluminum or an aluminum alloy having a light specific gravity and durability. As a result, the burden on the operator is reduced and the efficiency of the cleaning work is improved. Further, in order to further reduce the weight of the heat transfer tube cleaning tool 1, as shown in FIGS. 6 and 7, an opening 7 is provided in the plate surface obtained by cutting out the plate material inside the plate-shaped portion of the cleaning portion 2. May be formed in a ladder shape by providing a plurality of openings 7. The cleaning portion 2 is not limited to the case of a ladder shape, and may be, for example, a punching metal having a plurality of circular openings formed therein. By providing the opening 7, the strength and rigidity of the heat transfer tube cleaning tool 1 are not significantly reduced, and the weight is further reduced by lightening and the workability is improved.

Further, in the above-described embodiment, the case where the heat transfer tube cleaning tool 1 has a linear shape in the longitudinal direction has been described, but the present invention is not limited to this example. For example, as shown in FIGS. 6 and 7, at least a part of one end side to be gripped by the operator is bent in one direction, and the handle portion 3 projects from the plate-shaped portion of the cleaning portion 2. It may have a shape. This makes it easier for the operator to grip the heat transfer tube cleaning tool 1. Further, even if the hand comes off from the handle portion 3 during the cleaning work and the heat transfer tube cleaning tool 1 is dropped, the handle portion 3 is located near the upper part of the heat transfer tube 14 or the fin 15 of the heat exchanger 13. Since it is caught, there is no risk that all of the heat transfer tube cleaning tool 1 will enter deep inside the heat exchanger 13, and it is possible to prevent the heat transfer tube cleaning tool 1 from remaining inside the heat exchanger 13 and taking time to recover. it can.

The heat transfer tube cleaning tool 1 repeats a vibrating operation by pushing and pulling and rubbing about 3 to 5 times with a stroke within its longitudinal length (1 m to 3 m), and then the longitudinal axis of the heat transfer tube 14. The width of the heat transfer tube cleaning tool 1 (150 mm to 300 mm) is shifted in the direction, and the vibration operation by pushing and pulling and rubbing is repeated in the same manner. Then, the entire heat exchanger 13 (heat transfer tube group) is subjected to the vibration excitation operation by pushing and pulling and rubbing as described above. Further, also in the heat transfer tubes 14 and fins 15 located deep in the heat exchanger 13, the heat transfer tubes 14 and fins 15 can be vibrated in sequence to wipe off the coating film pieces on the entire heat transfer tubes 14 of the heat exchanger 13. it can.

From the above, the coating pieces that have been peeled off and accumulated or accumulated by the vibration operation using the heat transfer tube cleaning tool 1 are wiped off vertically downward, and the adhesive force is applied to the outer surfaces of the heat transfer tube 14 and the fins 15. The coated piece with the reduced amount is peeled off from the heat transfer tube 14 and the fins 15 and falls vertically downward by gravity. At this time, the coating film piece peeled off from the heat transfer tube 14 or the fin 15 on the vertically upper side may be deposited on the upper surface of the heat transfer tube 14 or the fin 15 on the vertically lower side in the vertical direction. Compressed air is sprayed by an air nozzle (not shown) prepared separately to blow the deposited coating film piece, so that the deposited coating film falls vertically downward and is removed from the outer surface of the heat transfer tube 14 and the fin 15. ..

When vibrating the heat transfer tube 14 and the fins 15, in the present embodiment, a heat transfer tube cleaning tool 1 having a simple structure is used instead of using an electric vibration exciter. Then, the heat transfer tube cleaning tool 1 can be repeatedly pushed and pulled and rubbed like a bow of a stringed instrument to easily generate self-excited vibration with respect to the heat transfer tube 14 corresponding to the strings of the stringed instrument. As a result, the coating film pieces deposited on the heat transfer tube 14 and the fin 15 are vibrated and wiped off vertically downward, or the coating film having a reduced adhesive force is easily peeled off from the heat transfer tube 14 and the fin 15 and vertically downward. You can pay it off.

Further, according to the present embodiment, since the cleaning method is a dry method that does not use water or chemicals, there is no possibility that corrosion will occur in the heat transfer tube 14 and the fins 15. Further, unlike the hammering method, the heat transfer tube 14 and the fins 15 can be vibrated without giving a strong impact to the heat transfer tube 14, the fins 15, the header, the connecting rods connecting the heat transfer tubes 14 to each other, and the like. And the deformation of the fin 15 can be prevented. Further, unlike the case of using an electric vibration device (vibrator), it is not necessary to select a vibration point or reinforce the heat transfer tube 14, and it is possible to reduce an increase in equipment cost.

Further, even when the distance between the heat transfer tubes 14 and the fins 15 is narrow, according to the present embodiment, the plate-shaped heat transfer tube cleaning tool 1 is placed in the vertical direction in which the heat transfer tubes 14 are laminated. The heat transfer tube 14 and fins 15 can be easily vibrated by generating self-excited vibration just by inserting the heat pipe diagonally and sliding the heat transfer tube 14 and fins 15. In this case as well, the heat transfer tube 14 and the fins 15 can be vibrated to wipe off the coating pieces on all of the heat transfer tubes 14 and the fins 15 of the heat exchanger 13.

[Second Embodiment]
Next, the heat transfer tube cleaning tool according to the second embodiment of the present invention will be described. It should be noted that detailed description of the configuration and the action and effect overlapping with the first embodiment will be omitted.
In the above-described embodiment, the case where the heat transfer tube cleaning tool 1 is composed of the cleaning portion 2 of the plate-shaped member of the flat plate or the corrugated plate and the handle portion 3 has been described, but the present invention is not limited to this example. For example, as shown in FIGS. 8 and 9, the plate-shaped receiving plate 8 parallel to the plate-shaped portion of the cleaning portion 2 is located below the plate-shaped portion of the cleaning portion 2 in the vertical direction during cleaning. It may be provided.

The plate-shaped member of the cleaning unit 2 and the receiving plate 8 are arranged so as to face each other, and the receiving plate 8 is connected to the cleaning unit 2 via the connecting member 9 on one end side. The distance between the cleaning unit 2 and the receiving plate 8 is substantially equal to the distance between the gap between the adjacent heat transfer tubes 14 and fins 15 and the gap between the heat transfer tubes 14 and fins 15. When inserting the heat transfer tube cleaning tool 1, the cleaning section 2 and the receiving plate 8 are inserted so as to sandwich the heat transfer tube 14 and the fins 15 located vertically below the cleaning section 2 of the heat transfer tube cleaning tool 1. While the cleaning work is being performed, as shown in FIG. 8, the receiving plate 8 can receive the coating film pieces that have been wiped off by the self-excited vibration in the heat transfer tube 14 and the fins 15 generated by the cleaning unit 2. .. Further, the received coating film piece may be concentratedly dropped from the tip of the receiving plate 8 at a predetermined position, or may be accumulated in the receiving plate 8 by providing a barb at the tip of the receiving plate 8.

In the receiving plate 8, the dropped coating film piece does not fall directly on the heat transfer tube 14 or fin 15 on the lower side in the vertical direction, and the coating film piece is deposited on the heat transfer tube 14 or fin 15 on the lower stage side. Receive the peeled coating film piece on the lower surface side of the cleaning unit 2 so as not to prevent it.

While the cleaning work is being performed, the peeled coating film pieces that have been wiped off on the receiving plate 8 are accumulated, so that the coating film pieces are suppressed from being deposited on the heat transfer tube 14 on the vertically lower side. Further, as shown in FIG. 8, since the coating film pieces P accumulated along the receiving plate 8 are concentrated and dropped at a predetermined position, the coating film pieces P can be concentrated and accumulated at a predetermined position. It will be possible. By concentrating and accumulating the coating film pieces P, it is possible to simplify the blowing operation of the compressed air injection by the air nozzle.

1: Heat transfer tube cleaning tool 2: Cleaning part 3: Handle part 4: Opening 5: Mountain part 6: Valley part 7: Opening 8: Receiving plate 9: Connecting member 12: Duct 13: Heat exchanger 14: Heat transfer tube 15: Fin

Claims (8)

A method of cleaning a heat exchanger using a heat transfer tube cleaner having a plate-shaped member long in one direction.
A step of bringing at least a part of the plate-shaped member into contact with the heat transfer tube of the heat exchanger or the fins provided on the outer peripheral surface of the heat transfer tube.
The plate-shaped member is slid with respect to the heat transfer tube or the fin, and the heat transfer tube or a part of the fin is self-made by the frictional force between the heat transfer tube or the fin and the plate-shaped member. A step of generating exciting vibration and removing dust accumulated or adhering to the heat transfer tube or the fin by self-excited vibration.
How to clean the heat exchanger. The method for cleaning a heat exchanger according to claim 1, wherein the plate-shaped member has a flat plate shape. The method for cleaning a heat exchanger according to claim 1, wherein the plate-shaped member has a corrugated plate shape. The method for cleaning a heat exchanger according to any one of claims 1 to 3, wherein a handle portion that can be gripped by an operator is formed on one end side of the plate-shaped member. The method for cleaning a heat exchanger according to claim 4, wherein the handle portion has a shape in which at least a part thereof projects in one direction with respect to the plate surface of the plate-shaped member. The method for cleaning a heat exchanger according to any one of claims 1 to 5, wherein the plate-shaped member has at least one opening formed in the plate surface. The heat transfer tube cleaning tool is plate-shaped, and further includes a receiving plate installed so as to face the plate surface of the plate-shaped member.
The heat according to any one of claims 1 to 6, wherein the receiving plate is arranged so as to be located vertically below the plate-shaped member in the step of generating self-excited vibration in the heat transfer tube or the fin. How to clean the exchanger. A method of cleaning a heat exchanger using a heat transfer tube cleaner having a plate-shaped member long in one direction.
A step of bringing at least a part of the plate-shaped member into contact with the heat transfer tube of the heat exchanger or the fins provided on the outer peripheral surface of the heat transfer tube.
The plate-shaped member is slid with respect to the heat transfer tube or the fin, and the heat transfer tube or a part of the fin is self-made by the frictional force between the heat transfer tube or the fin and the plate-shaped member. Steps to generate excitation vibration and
With
A handle portion that can be gripped by an operator is formed on one end side of the plate-shaped member.
A method for cleaning a heat exchanger having a shape in which at least a part of the handle portion projects in one direction with respect to the plate surface of the plate-shaped member.

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