JP2008175513A - Plate fin type heat exchanger, and warm air heater using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensively manufacturable plate fin type heat exchanger having a small number of parts, a simple composition, a sufficient heat transfer area, favorable heat exchange efficiency, and easy assembly, and to provide a warm air heater using it. <P>SOLUTION: A partition plate 11 has first flanges 11A, 11A formed by bending ends of two parallel sides facing each other respectively toward surface sides, and second flanges 11B, 11B formed by bending ends of two parallel other sides facing each other respectively toward rear face sides. They are alternately laminated by inverting the front and rear. Waveform fins 12 are positioned between the first flanges 11A, 11A, and between the second flanges 11B, 11B, and alternately arranged in mutually orthogonal directions, in a first fluid passage 14 and a second fluid passage 13 between the partition plates 11, and each waveform top part 12A is brazed to the partition plate 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plate fin type heat exchanger configured by alternately laminating flat partition plates and corrugated fins, and a hot air heater using the plate fin type heat exchanger.

  The partition plates and corrugated fins (corrugated fins) are alternately stacked to form two fluid flow paths that are orthogonal to each other between the partition plates, and two different fluids that are circulated through the two fluid flow paths. Cross-flow type plate fin heat exchangers that exchange heat with each other flow 2 across a partition plate in the field of air conditioning such as a ventilator and an air conditioner, or in the field of various industrial plants such as chemical plants and power plants. It is widely used as a heat exchanger for exchanging heat between seed fluids. As such a plate fin type heat exchanger, those having various configurations have been proposed.

As an example, Patent Document 1 discloses a pair of heat transfer plates (partition plates) and a space regulating member that is joined between these heat transfer plates, regulates the space between them, and extends along the fluid flow direction. Are shown in which a heat exchange element is configured by alternately stacking unit bodies including 90 and 90 degrees.
In Patent Documents 2 and 3, plate-like partition plates and corrugation fins that partition two fluid flow paths are alternately stacked, and the gap between the partition plates is maintained on both sides of each fluid flow path. A plate fin type heat exchanger configured by arranging spacer bars for sealing and brazing them together is shown.
Further, in Patent Document 4, a partition plate made of resin and shielding ribs in directions orthogonal to each other at opposite ends of the front and back surfaces, and a plurality of spacing ribs provided in parallel at predetermined intervals between the shielding ribs. A heat exchanging element configured by alternately laminating a plurality of resin heat exchanging plates having the structure is shown.

JP-A-11-201666 JP-A-7-167579 JP 2001-349679 A JP 2003-287387 A

However, the configuration described in Patent Document 1 has a problem that the manufacturing cost increases because the integral formation of the gap regulating member and the heat transfer plate requires extrusion molding or pultrusion molding. In addition, when the interval regulating member and the heat transfer plate are separated, it is necessary to individually bond the interval regulating member to the heat transfer plate, which complicates the positioning and joining work at the time of joining, and further improves the heat transfer performance. There is a problem that there is a limit to increasing the number by reducing the thickness of the interval regulating member in order to increase it.
In the configurations described in Patent Documents 2 to 3, the separation plate must be kept on both sides of the fluid flow path, and spacer bars for sealing the flow path must be disposed, resulting in an increase in the number of parts. The cost is high, and when the spacer bar, fins, and partition plate are temporarily assembled and loaded into a vacuum furnace and brazed, the spacer bar is likely to fall over, and the productivity is lowered to prevent it. Have problems such as.
Further, in the configuration described in Patent Document 4, since the partition plate and the heat exchange plate are made of resin, not only the use range is limited by the temperature of the fluid to be heat exchanged, but also the heat transfer area is increased and the heat transfer performance is improved. In order to improve, it is necessary to increase the number by thinning the spacing ribs, but there are problems such as limitations in terms of adhesion to the partition plate and workability.

  The present invention has been made in view of such circumstances, has a small number of parts, has a simple structure, has a sufficient heat transfer area, has good heat exchange efficiency, is easy to assemble, and has a low level. It aims at providing the plate fin type heat exchanger which can be manufactured at cost, and a warm air heater using the same.

In order to solve the above problems, the plate fin type heat exchanger of the present invention and the hot air heater using the same adopt the following means.
That is, the plate fin type heat exchanger according to the present invention is configured by alternately laminating flat partition plates and corrugated fins, and the first fluid flow path and the second fluid flow perpendicular to each other between the partition plates. In a plate fin type heat exchanger that alternately forms a channel and exchanges heat between two different fluids flowing in the first fluid channel and the second fluid channel, the partition plates are arranged in parallel with each other. A first flange formed by bending the end portions of the two sides to the front surface side, and a second flange formed by bending the end portions of the other two opposite parallel sides to the back surface side, respectively The fins are alternately stacked with the front and back reversed, and the fins are positioned between the first flange and the second flange in the first fluid channel and the second fluid channel between the partition plates, respectively. Orthogonal to each other Alternately disposed in a direction, characterized in that each waveform apex is brazed joint to each of the partition plate.

  According to the present invention, the partition plates formed with the first flange and the second flange by bending the ends of two opposite parallel sides to the front side and the back side, respectively, are alternately stacked with the front and back reversed, Corrugated fins are positioned between the partition plates by the first flange and the second flange and alternately arranged in directions orthogonal to each other, and the corrugated tops of these corrugated fins are brazed and joined to the partition plates, respectively. By doing so, a plate fin type heat exchanger having a first fluid channel and a second fluid channel that are orthogonal to each other and partitioned into a plurality of channels by corrugated fins can be configured. Thus, with the minimum number of parts, the first fluid channel and the second fluid channel are each divided into a plurality of separated channels by corrugated fins, and have a sufficient heat transfer area, and the partition plate It is possible to manufacture a plate fin type heat exchanger that has a low heat transfer resistance between the undulating fins, good heat exchange efficiency, easy assembly and a simple configuration at low cost.

  Furthermore, the plate fin type heat exchanger of the present invention is the above plate fin type heat exchanger, wherein the first flange has an end that is over when the partition plates are alternately stacked with the front and back reversed. One of the first fluid flow paths is partitioned by having an overlapping height and the overlapping portions are brazed and joined to each other.

  According to the present invention, the first flange has a height at which the end portions overlap each other when the partition plates are alternately stacked with the front and back reversed, and the overlap portions are brazed and joined to each other. Accordingly, since one of the separation channels of the first fluid channel is partitioned, the number of channels of the first fluid channel can be increased and the effective heat transfer area can be increased. Thereby, heat exchange performance can be improved.

  Furthermore, the plate fin type heat exchanger of the present invention is any one of the above plate fin type heat exchangers, wherein the core portion of the heat exchanger is composed of only two types of parts, the partition plate and the fins. It is characterized by being configured.

  According to the present invention, since the core part of the heat exchanger is composed of only two types of parts, that is, the partition plate and the fins, the number of components cannot be minimized, and the parts in the manufacturing process. Simplification of management and assembly process can be achieved. Therefore, the manufacturing cost of the plate fin type heat exchanger can be greatly reduced. In order to form the core portion by using only two types of parts, that is, the partition plate and the fin, the ratio between the width direction dimension and the length direction dimension of the partition plate and the fin is basically 1: 1. However, if the dimension in the length direction of the partition plate is an integral multiple of the dimension in the width direction, a plurality of fins are connected in the length direction so that two fins having different lengths can be prepared. It is possible to cope with only a kind of parts.

  Furthermore, the plate fin type heat exchanger according to the present invention is the plate fin type heat exchanger according to any one of the above-described plate fin type heat exchangers. Low temperature air is circulated through the passage, and exhaust heat is recovered from the combustion exhaust gas by low temperature air circulated through the second fluid flow path.

  According to the present invention, high-temperature combustion exhaust gas is circulated in the first fluid flow path, and low-temperature air is circulated in the second fluid flow path, and the low-temperature circulated through the second fluid flow path. Since exhaust heat can be recovered from combustion exhaust gas by air, the plate fin type heat exchanger can be effectively used as an exhaust heat recovery device from combustion exhaust gas to air, which can contribute to the improvement of the thermal efficiency of the equipment used.

  Furthermore, the hot air heater according to the present invention includes a blower that circulates air, a combustion chamber that burns fuel, and heat that exchanges heat between air circulated by the blower and combustion gas burned in the combustion chamber. And a hot air heater that blows out the air heated by the heat exchanger as hot air, wherein any one of the plate fin heat exchangers described above is disposed in a combustion exhaust gas passage for discharging the combustion gas. It arrange | positions and collect | recovers exhaust heat to the air side circulated by the said air blower from combustion exhaust gas, It is characterized by the above-mentioned.

  According to the present invention, any one of the above-described plate fin heat exchangers is disposed in the combustion exhaust gas passage of the hot air heater that blows out the air heated by the combustion gas as warm air, and the circulating air is discharged from the combustion exhaust gas. Since the exhaust heat can be recovered to the side, the exhaust heat of the combustion exhaust gas can be effectively used to improve the thermal efficiency of the hot air heater.

According to the plate fin heat exchanger of the present invention, the first fluid channel and the second fluid channel are each divided into a plurality of separated channels by corrugated fins with a minimum number of components, and sufficient transmission is achieved. A plate fin type heat exchanger having a heat area, a small heat transfer resistance between the partition plate and the corrugated fins, good heat exchange efficiency, easy assembly and simple configuration can be manufactured at low cost. .
In addition, according to the hot air heater of the present invention, a plate fin type heat exchanger is disposed in the combustion exhaust gas flow path, and exhaust heat can be recovered from the combustion exhaust gas to the circulating air side. The thermal efficiency of the hot air heater can be improved by effectively using heat.

Embodiments according to the present invention will be described below with reference to the drawings.
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.
The schematic block diagram of the hot air heater 1 which concerns on 1st Embodiment of this invention is shown by FIG. The warm air heater 1 burns fuel such as gas and kerosene, heats the air by the heat of the combustion gas, generates warm air, and uses it for heating. The warm air heater 1 includes a cabinet body 2 and a combustion chamber 4 in which fuel and air ejected from a burner 3 are combusted. In addition, a blower 5 that circulates air is provided in the cabinet body 2, and air sucked from outside is blown to the heat exchange unit 6, and hot air generated in the heat exchange unit 6 is blown out from the blowout port 7. It is said that.

  The heat exchanging unit 6 is a part that exchanges heat between the combustion gas burned in the combustion chamber 4 and the low-temperature air blown from the blower 5 and heats the air to generate hot air. The heat exchanging section 6 generally employs a configuration in which low temperature air is circulated around a smoke pipe or a heat exchanging cylinder through which combustion gas is circulated and heated to a predetermined temperature. The combustion gas that has circulated through the heat exchanging unit 6 is discharged from the heat exchanging unit 6 to a combustion exhaust gas flow path (chimney) 8 and exhausted outside as combustion exhaust gas. An exhaust heat recovery device (heat exchanger) 9 for recovering exhaust heat from the combustion exhaust gas is installed in the middle of the combustion exhaust gas flow path 8.

The exhaust heat recovery unit (heat exchanger) 9 adopts a cross-flow type plate fin type heat exchanger in which two fluids of combustion exhaust gas and air are circulated through two orthogonal fluid flow paths to exchange heat with each other. Is done. Combustion exhaust gas has a temperature of a few hundreds of degrees Celsius, and heats the low-temperature air at room temperature by the exhaust heat and sucks it through the air duct 10 to the suction side of the blower 5 to collect the exhaust heat. It is said that.
As shown in FIG. 2, the plate fin type heat exchanger that constitutes the exhaust heat recovery unit 9 is formed by alternately laminating flat partition plates 11 and corrugated fins 12. The air side flow path 13 and the exhaust gas side flow path 14 which are orthogonal to each other are alternately formed, heat exchange is performed between the air and the combustion exhaust gas, and the exhaust heat is recovered from the combustion exhaust gas side to the air side.

  As shown in FIG. 3, the partition plate 11 is a square-shaped stainless steel flat plate in which the ratio of the width direction dimension L1 and the length direction dimension L2 is 1: 1, and two parallel sides facing each other. The first flanges 11A and 11A formed by bending the end portions of the first and second sides to the front surface side, and the second flanges 11B and 11B formed by bending the end portions of the other two opposite parallel sides to the back surface side, respectively. Have. The first flange 11A is higher than the second flange 11B, and when the partition plate 11 is laminated with the corrugated fins 12 disposed therebetween with the front and back reversed as described below, It has a height at which the ends overlap.

  The wave-shaped fins 12 are formed from a stainless steel thin plate, and as shown in FIG. 4, the fins 12 have a square shape in which the ratio between the width direction dimension M1 and the length direction dimension M2 is 1: 1. The plate 11 is positioned and disposed between the first flanges 11A and 11A and the second flanges 11B and 11B, and the corrugated top portions 12A are brazed and joined to the partition plate 11, respectively. By the corrugated fins 12, the air side flow path 13 and the exhaust gas side flow path 14, which are orthogonal to each other between the partition plates 11, are divided into a plurality of flow paths 13A and 14A, respectively.

The wave pitch of the corrugated fins 12 and the height thereof can be arbitrarily set according to performance and application, and the top 12A is securely brazed to the partition plate 11. It is desirable to provide a surface with a constant width.
As shown in FIG. 2, the exhaust heat recovery unit 9 sequentially stacks the partition plate 11 and the corrugated fins 12 by a necessary capacity with a brazing material interposed therebetween. The core portion 15 can be configured by brazing between the tops of 11 and the corrugated fins 12 and between the first flanges 11 </ b> A and 11 </ b> A of the upper and lower partition plates 11.

  For example, the lamination of the partition plate 11 and the corrugated fin 12 is performed by inserting a brazing material between the second flanges 11B and 11B on the back surface side of the partition plate 11 placed with the first flanges 11A and 11A facing downward. Two pieces are formed by positioning and arranging the shape fins 12 and laminating the partition plate 11 with the brazing material thereon, with the first flanges 11A and 11A facing up, that is, with the front and back reversed. An air-side channel 13 composed of a plurality of channels 13A partitioned by the corrugated fins 12 can be formed between the partition plates 11.

  Further, the corrugated fins 12 are positioned and disposed 90 degrees apart by interposing a brazing material between the upward first flanges 11A, 11A of the partition plate 11, and the brazing material is disposed thereon. Then, the partition plate 11 is laminated so that the first flanges 11A and 11A face downward, and the plurality of flow paths 14A partitioned by the corrugated fins 12 between the two partition plates 11 are stacked. An exhaust gas side flow path 14 composed of In the exhaust gas side flow path 14, the ends of the first flanges 11 </ b> A and 11 </ b> A of the upper and lower partition plates 11 that are alternately stacked with the front and back reversed are overlapped, and the overlap portions are brazed and joined together. Thus, the flow paths 14A can be partitioned at both end portions in the width direction. For this reason, the number of the flow paths 14A can be increased and the effective heat transfer area can be increased.

  As described above, a predetermined capacity is obtained by stacking the partition plate 11 and the corrugated fins 12 as many as necessary so that the air-side flow passages 13 and the exhaust gas-side flow passages 14 are alternately formed. A plate fin type heat exchanger as the exhaust heat recovery device 9 can be manufactured. As shown in FIG. 1, in this plate fin type heat exchanger, the exhaust gas side flow path 14 is communicated with the combustion exhaust gas flow path 8 at an orthogonal portion between the combustion exhaust gas flow path 8 and the air duct 10, and the air side flow path By installing 13 in communication with the air duct 10, the exhaust heat recovery device 9 can be functioned.

According to this embodiment described above, the following operational effects are obtained.
In the hot air heater 1, when the burner 3 is ignited, fuel such as gas and kerosene is combusted in the combustion chamber 3, and this combustion gas is circulated to the heat exchange unit 6. On the other hand, room air is sucked into the cabinet body 2 by the blower 5 and is circulated through the heat exchanging unit 6 to exchange heat with the combustion gas. As a result, the low-temperature air is heated to become hot air, and is blown out from the blowout port 7 for heating.

The combustion gas heat-exchanged with the air in the heat exchange part 6 is discharged | emitted from the heat exchange part 6 to the combustion exhaust gas flow path 8, and is exhausted outside. During this time, heat is exchanged with the air sucked through the air duct 10 in the exhaust heat recovery unit 9 installed in the middle of the combustion exhaust gas flow path 8, and the exhaust heat is recovered. The combustion exhaust gas discharged from the heat exchange unit 6 has a temperature of a few hundreds of degrees Celsius, and by collecting the exhaust heat to the air side circulated to the heat exchange unit 6 by the blower 5, The fuel consumption of the heater 1 can be reduced and the thermal efficiency can be improved.
Incidentally, by providing the exhaust heat recovery device 9 as described above, it was possible to increase the thermal efficiency from 82% to 90%.

  Further, the exhaust heat recovery device 9 (plate fin type heat exchanger) is a partition in which the first flange 11A and the second flange 11B are formed by bending the ends of two opposite parallel sides to the front side and the back side, respectively. The plates 11 are alternately laminated with the front and back reversed, and the corrugated fins 12 are positioned between the partition plates 11 by the first flange 11A and the second flange 11B and alternately arranged in directions orthogonal to each other. . The corrugated top 12A of the corrugated fin 12 is brazed and joined to the partition plate 11, respectively, so that the corrugated fin 12 is partitioned into a plurality of fluid passages 13A and 14A, respectively, and the air side passage 13 and the exhaust gas side that are orthogonal to each other The heat exchanger is configured to have a flow path 14. With this heat exchanger, the exhaust heat can be recovered from the high-temperature combustion exhaust gas flowing through the exhaust gas side flow path 14 by the low-temperature air side flowing through the air side flow path 13, and this can be recovered from the combustion exhaust gas to the air. By effectively using as a waste heat recovery device, it is possible to contribute to improving the thermal efficiency of the hot air heater 1.

Thus, the exhaust heat recovery unit 9 (plate fin type heat exchanger) can configure the core portion 15 by only two types of components, that is, the partition plate 11 and the fins 12, thereby minimizing the number of components. can do. Further, it is possible to simplify the parts management and the assembly process in the manufacturing process. Therefore, the manufacturing cost of the plate fin type heat exchanger can be greatly reduced.
In addition, since the air-side flow path 13 and the exhaust gas-side flow path 14 are partitioned by the corrugated fins 12 into the plurality of separation flow paths 13A and 14A, the air-side flow path 13 and the exhaust gas-side flow path 14 have sufficient heat transfer areas. Since the corrugated fins 12 are brazed, the heat recovery resistance is small, the heat exchange efficiency is good, the configuration is simple, and the exhaust heat recovery device 9 (plate fin type heat exchanger) that is easy to assemble can be obtained. it can.

Further, when the first flanges 11A are alternately stacked with the partition plates 11 turned upside down, the end portions overlap each other, and the overlap portions are brazed and joined to each other. Since one of the separation channels 14A of the side channel 14 is configured to be partitioned, the number of separation channels 14A in the exhaust gas side channel 14 can be increased, and the effective heat transfer area can be increased. Therefore, the heat exchange performance can be improved accordingly.
The partition plate 11 and the corrugated fins 12 are made of stainless steel and have sufficient strength and heat resistance as the high-temperature exhaust heat recovery device 9.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
This embodiment differs in the structure of the partition plate 21 with respect to the said 1st Embodiment. Since other points are the same as those in the first embodiment, description thereof will be omitted.
In the present embodiment, as shown in FIG. 5, the configuration of the partition plate 21 is such that the length direction dimension L3 is made to be a rectangular shape with a dimensional ratio of 1: 2 with respect to the width direction dimension L1. The first flanges 21A and 21A bent to the surface side are provided at the ends of the two parallel sides facing each other in the length direction of the partition plate 21, and at the ends of the other two parallel sides facing each other, Second flanges 21 </ b> B and 21 </ b> B bent on the back side are provided.

Even when the partition plate 21 is configured to have a rectangular shape with the dimensional ratio as described above, the core portion 15 can be configured by only two types of components, that is, the partition plate 21 and the corrugated fins 12. In other words, in order to configure the core portion 15 by only two types of parts, that is, the partition plate 11 or 21 and the corrugated fin 12, the width direction dimensions of the partition plate 11 and the corrugated fin 12 are set as in the first embodiment. Basically, the ratio to the lengthwise dimension is 1: 1 respectively, but the lengthwise dimension of the partition plate 21 is an integral multiple of the widthwise dimension (2 in this embodiment) as in this embodiment. 2), by connecting a plurality of corrugated fins 12 in the length direction, it is possible to cope with only two types of components without preparing two corrugated fins having different lengths. Become.
Therefore, the shape of the exhaust heat recovery unit 9 (plate fin type heat exchanger) can also be appropriately selected according to the installation space and the like.

In addition, this invention is not limited to each above-mentioned embodiment, In the range which does not deviate from the summary, it can change suitably. For example, although the heat exchanger concerning this invention demonstrated the example applied to the exhaust heat recovery device 9 of the warm air heater 1, it is not limited to this, The general cross-flow system which heat-exchanges two different fluids As a heat exchanger, high-pressure fluid is used in other air-conditioning equipment and various industrial plants, and it is widely applied except when pressure resistance is required for the flow path composed of a pair of partition plates. be able to.
Moreover, although the said embodiment demonstrated the example which comprises the core part 15 only with two types of components, the partition plate 11 or 21, and the waveform fin 12, two types of waveform fins from which length differs were prepared. For example, in the width direction and the length direction, a core portion having any dimensional ratio can be configured, and such an embodiment is also included in the scope of the present invention.

It is a schematic block diagram of the warm air heater which concerns on 1st Embodiment of this invention. It is a fragmentary perspective view of the waste heat recovery device (plate fin type heat exchanger) used for the warm air heater concerning a 1st embodiment of the present invention. It is a perspective view of the partition plate which comprises the waste heat recovery device (plate fin type heat exchanger) shown in FIG. It is a perspective view of the wave-shaped fin which comprises the exhaust heat recovery device (plate fin type heat exchanger) shown in FIG. It is a perspective view of the partition plate which comprises the waste heat recovery device (plate fin type heat exchanger) which concerns on 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hot air heater 4 Combustion chamber 5 Blower 6 Heat exchange part 8 Combustion exhaust gas flow path 9 Waste heat recovery device (plate fin type heat exchanger)
DESCRIPTION OF SYMBOLS 10 Air duct 11, 21 Partition plate 11A, 21A 1st flange 11B, 21B 2nd flange 12 Corrugated fin 12A Waveform top part 13 Air side flow path (2nd fluid flow path)
13A Separation channel 14 Exhaust gas side channel (first fluid channel)
14A Separation flow path 15 Core part

Claims (5)

The first fluid channel is formed by alternately laminating flat partition plates and wave-shaped fins, and alternately forming first fluid channels and second fluid channels orthogonal to each other between the partition plates. And a plate fin type heat exchanger for exchanging heat between two different fluids circulated in the second fluid flow path,
The partition plate is formed by bending the end portions of two opposite parallel sides to the front surface side, and bending the other opposite two side ends to the back surface side. Having a second flange and being alternately stacked with the front and back reversed.
The fins are positioned alternately between the first flange and the second fluid channel between the partition plates in a direction perpendicular to each other, positioned between the first flange and the second flange, respectively. The plate fin type heat exchanger is characterized in that each corrugated top is brazed and joined to the partition plate.   The first flange has a height at which ends overlap when the partition plates are alternately stacked with the front and back reversed, and the overlapping portions are brazed and joined to each other. The plate fin type heat exchanger according to claim 1, wherein one of the one fluid flow paths is partitioned.   3. The plate fin heat exchanger according to claim 1, wherein the core portion of the heat exchanger is configured by only two types of parts, the partition plate and the fin. 4.   A high-temperature combustion exhaust gas is circulated in the first fluid channel, and low-temperature air is circulated in the second fluid channel, and the low-temperature air circulated in the second fluid channel The plate fin type heat exchanger according to any one of claims 1 to 3, wherein exhaust heat is recovered from the combustion exhaust gas. A blower that circulates air; a combustion chamber that burns fuel; and a heat exchange unit that exchanges heat between the air circulated by the blower and the combustion gas burned in the combustion chamber, and is heated by the heat exchange unit In the hot air heater that blows out the generated air as hot air,
The plate fin type heat exchanger according to any one of claims 1 to 4 is disposed in a combustion exhaust gas flow path for discharging the combustion gas, and exhaust heat is recovered from the combustion exhaust gas to the air side circulated by the blower. A warm air heater characterized by

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