JP4899197B2 - Heat exchanger for dehumidification of large capacity compressed air - Google Patents

Description

  The present invention relates to an improvement in a shell-and-tube heat exchanger that reuses compressed air that has been cooled and dehumidified to a low temperature for cooling high-temperature compressed air before dehumidification. The present invention relates to a heat exchanger for dehumidification of large-capacity compressed air suitable for use as a heat exchanger for dehumidifying the air.

  Conventionally, Patent Document 1 discloses an improved heat exchanger of a compressed air dehumidifier. This heat exchanger is a shell and tube type, and forms a cylindrical outer cylinder and an inner cylinder corresponding to the shell, and after inserting the inner cylinder into the outer cylinder, a refrigeration cycle corresponding to a tube in the inner cylinder The heat exchanger is easily assembled by inserting and fixing the evaporator.

  That is, according to this heat exchanger, the inner cylinder is arranged in the cylindrical outer cylinder at a predetermined interval, the evaporator of the refrigeration cycle is arranged in the inner cylinder, and the gap between the outer cylinder and the inner cylinder is arranged. Is a heat exchanger in which a heat transfer tube is arranged. Then, by caulking the outer cylinder, the inner cylinder can be fixed without welding.

Japanese Patent No. 2516156

  According to the heat exchanger shown in Patent Document 1, assembly is easier than in the conventional structure, but as in Patent Document 1, an evaporator consisting of a refrigerant pipe and baffle fins is set and inserted into the inner cylinder. This is limited to relatively small heat exchangers and is not suitable for large capacity heat exchangers. That is, in order to dehumidify a large volume of compressed air, more pipes for heat exchange are used as the capacity of the compressed air increases. Therefore, as in Patent Document 1, when an evaporator consisting of a refrigerant pipe and a baffle fin is set and inserted into the inner cylinder, the weight of the evaporator increases as the volume of compressed air increases, This makes it difficult to insert it into the inner cylinder.

  Moreover, the heat exchange pipe through which the refrigerant circulates is set so that the pressure inside the pipe is higher than the pressure inside the tank, and piping work is required to have extremely high accuracy. Therefore, as in Patent Document 1, it is unavoidable to employ a means for assembling and forming an evaporator of a refrigeration cycle corresponding to a tube in advance and mounting it in a tank. Therefore, the heat exchanger of patent document 1 is limited to a comparatively small-scale heat exchanger.

  Moreover, the heat exchanger used for dehumidification of large capacity compressed air needs to reduce the pressure loss for heat exchange as much as possible. To that end, it is necessary to increase the area of the heat exchanger pipe so that the flow rate of the compressed air does not decrease. As a result, the number of heat exchanger pipes used increases and the weight of the entire heat exchanger increases. Become. That is, when the shell-and-tube heat exchanger has a large capacity, the weight of the entire heat exchanger becomes extremely heavy, making it difficult to manufacture, transport, or install the heat exchanger.

  Therefore, the present invention has been devised to solve the above-mentioned problems, and it is possible to manufacture a heat exchanger with little pressure loss in heat exchange even when a large volume of compressed air with increased compressed air capacity and flow velocity is circulated. An object of the present invention is to provide a heat exchanger for dehumidification of large-capacity compressed air that can be easily transported and installed even if the weight of the heat exchanger increases.

In order to achieve the above-mentioned object, the first means in the present invention is to arrange a heat exchange pipe 4 for circulating the high-temperature compressed air before dehumidification in the tank 1 for supplying the low-temperature compressed air after cooling and dehumidification. In the shell-and-tube heat exchanger, a plurality of insertion holes 3A through which the heat exchange pipe 4 is inserted are formed, and a pair of tube plates 3 are provided so that the heat exchange pipe 4 is retrofitted into the insertion hole 3A. The outer peripheral surface of the tube plate 3 and the inner peripheral surface of the tank 1 are brought into close contact with each other, the tube plate 3 is fixed to both ends of the tank 1, and the pair of end plates 5 covering both ends of the tank 1 are attached to and detached from the tank 1. The heat exchange pipe 4 and the end plate 5 are provided so as to be freely mounted, and are transported in a state of being disassembled from the tank 1, and the low temperature after cooling and dehumidification supplied into the tank 1 Pre-distribution plate 2 that changes the flow of compressed air A large number of insertion holes 2A through which the heat exchange pipe 4 is inserted are opened in the flow dividing plate 2, and when the heat exchange pipe 4 is inserted into the tube plate 3, the heat exchange pipe 4 is It is also configured to support the side surface of the heat exchanging pipe 4 by passing through the flow dividing plate 2, and the difference between the pressure of the compressed air in the tank 1 and the pressure of the compressed air in the heat exchanging pipe 4 is The setting is within 0.1 KPa .

  As in claim 1 of the present invention, a pair of tube plates 3 for retrofitting the heat exchange pipe 4 is provided, and the outer peripheral surface of the tube plate 3 and the inner peripheral surface of the tank 1 are brought into close contact with each other at both ends of the tank 1. A tube plate 3 is fixed, and a pair of end plates 5 covering both ends of the tank 1 are detachably attached to the tank 1, and the heat exchange pipe 4 and the end plate 5 are disassembled from the tank 1. By being configured to be transported, it can be easily transported even if the weight of the heat exchanger increases. As a result, it is easy to manufacture a large-capacity heat exchanger with little pressure loss for heat exchange even when the capacity and flow rate of compressed air increase. In addition, after the heat exchange pipe 4 and the end plate 5 are transported in a state of being disassembled from the tank 1, they can be easily assembled on site, so that the installation work of the large capacity heat exchanger with increased weight can be easily performed. It can be done.

Further , since the difference between the pressure of the compressed air in the tank 1 and the pressure of the compressed air in the heat exchange pipe 4 is set within 0.1 KPa, even if the heat exchange pipe 4 is attached later. There is no risk of compressed air leaking from the joint portion of the heat exchange pipe 4, and this heat exchanger can be used without any problems even if it is assembled on site.

Further , the flow dividing ratio can be increased by controlling the flow of the compressed air by the flow dividing plate 2. Further, since the insertion hole 2A is opened in the flow dividing plate 2, the heat exchange pipe 4 is supported by the intermediate portion of the tank 1 when a large number of heat exchange pipes 4 are mounted inside the tank 1. It functions also as an auxiliary support plate, and can be supported in a stable state even if the weight of the heat exchange pipe 4 as a whole increases.

It is a schematic sectional side view which shows one Example of this invention. It is a front view which shows the Example of the tube sheet of this invention. It is a front view which shows the bottom part 2 Example of this invention. It is a schematic sectional side view which shows the other Example of this invention.

  According to the present invention, it becomes easy to manufacture a large-capacity heat exchanger with little pressure loss for heat exchange even if the capacity and flow rate of compressed air are increased, and transportation is possible even if the weight of the heat exchanger increases. It achieves the original goal of being easy.

  An embodiment of the present invention will be described below. The heat exchanger of the present invention is a shell-and-tube heat exchanger, supplying low-temperature compressed air after cooling and dehumidification into the tank 1 (shell), and before dehumidifying into the heat exchange pipe 4 (tube). It is a heat exchanger called an economizer used for the purpose of efficiently dehumidifying a large volume of compressed air by circulating high-temperature compressed air.

  The tank 1 has a large capacity in accordance with the capacity of the compressed air, and the inside of both ends of the tank 1 is welded with a crocodile tube plate 3 in advance (see FIG. 1). The tube plate 3 is formed with a large number of insertion holes 3A through which a large number of heat exchange pipes 4 can be inserted, so that the heat exchange pipes 4 can be retrofitted to the insertion holes 3A at the installation site of the heat exchanger. Is provided. The tube plate 3 in the illustrated example has a circular shape that closely contacts the inner peripheral surface of the tank 1 (see FIG. 2), and the outer peripheral surface of the tube plate 3 and the inner peripheral surface of the tank 1 are welded to each other. Is fixed. Further, an air inlet 1C for blowing compressed air after dehumidification and an air outlet 1D for discharging compressed air after heat exchange are formed on the side surface of the tank 1.

  Further, a flow dividing plate 2 is welded in advance inside the tank 1. This flow dividing plate 2 changes the flow of the low-temperature compressed air after cooling and dehumidification supplied into the tank 1, and a number of insertion holes 2A through which the heat exchanging pipe 4 is inserted are also opened in this flow dividing plate 2. Has been. When the heat exchanging pipe 4 is inserted into the tube plate 3, the heat exchanging pipe 4 is also inserted into the flow dividing plate 2 to support the side surface of the heat exchanging pipe 4.

  The heat exchanging pipe 4 is transported separately from the tank 1 and inserted into the tube plate 3 or the diverter plate 2 at the installation site, and then the end of the heat exchanging pipe 4 is expanded and expanded into the tube plate 3. Weld. At this time, the difference between the pressure of the compressed air in the tank 1 and the pressure of the compressed air in the heat exchanging pipe 4 is set within 0.1 KPa, so that it functions sufficiently as a shell-and-tube heat exchanger. It is. If the pressure difference is high, there may be a problem that compressed air before dehumidification leaks into the tank 1. Therefore, although a slight difference occurs depending on the capacity of the tank 1 and the number of heat exchange pipes 4, a normal operation can be performed by setting at least the pressure difference within 0.1 KPa.

  Reference numeral 5 denotes a pair of end plates 5 that cover both ends of the tank 1. The end plate 5 is provided so as to be detachably attached to the opening of the tank 1, and is transported in a disassembled state from the tank 1, similar to the heat exchange pipe 4. The illustrated end plate 5 is formed with a connecting flange 5A connected to a connecting flange 1B projecting around the opening of the tank 1, and the connecting flange 1B and the connecting flange 5A are screwed together. These end plates 5 are each provided with an air inlet 5B for blowing high-temperature compressed air before dehumidification into the heat exchange pipe 4 and an air outlet 5C for discharging compressed air after heat exchange.

  The heat exchanger of the present invention shown in FIG. 1 shows a horizontal type. In this case, the high-temperature compressed air before dehumidification is supplied from the air inlet 5B of one end plate 5, passes through the heat exchange pipe 4, and is discharged from the air outlet 5C of the opposite end plate 5. The dehumidified low-temperature compressed air supplied from one air inlet 1C is heat-exchanged and discharged from the air outlet 1D.

  In addition, as shown in FIG. 4, the heat exchanger of the present invention can be a vertical type. In this case, one end plate 5 is provided with an air inlet 5B and an air outlet 5C, and a partition plate 6 for partitioning the interior surrounded by the end plate 5 is provided. The partition plate 6 can be provided in advance so as to partition the inside of the end plate 5 when the end plate 5 is assembled by fixing to the tube plate 3 or the end plate 5 in advance. Moreover, it is also possible to detachably attach the independent partition plate 6 to the tube plate 3 and the end plate 5.

  Then, the high-temperature compressed air before dehumidification supplied from the air inlet 5B shown in FIG. 4 passes through the heat exchanging pipe 4 and is folded back at the opposite end plate 5 portion, and another heat exchanging pipe 4 is connected again. While passing through and being discharged from the air outlet 5C, the low-temperature compressed air after dehumidification supplied from the air inlet 1C of the tank 1 is subjected to heat exchange and discharged from the air outlet 1D.

  In the heat exchanger of the present invention, the tank 1 in which the flow dividing plate 2 and the tube plate 3 are previously welded, a large number of heat exchange pipes 4 corresponding to a large volume of compressed air, and the end plate for sealing the opening of the tank 1. 5 and are assembled in the field where heat exchangers are used.

  In addition, each structure of this invention is not limited to the example of illustration, In the range which does not change the summary of this invention, it can change freely.

  The heat exchanger of the present invention can be used in various devices for dehumidifying a large volume of compressed air, and can perform efficient heat exchange using a temperature difference before and after dehumidification.

1 tank 1A opening 1B connection flange 1C air inlet 1D air outlet 2 flow dividing plate 2A insertion hole 3 tube plate 3A insertion hole 4 heat exchange pipe 5 end plate 5A connection flange 5B air inlet 5C air outlet 6 partition plate

Claims (1)

In a shell-and-tube heat exchanger in which a heat exchange pipe for circulating high-temperature compressed air before dehumidification is disposed in a tank that supplies low-temperature compressed air after cooling and dehumidification, the heat exchange pipe is inserted. A large number of insertion holes are formed, and a pair of tube plates are provided so that heat exchange pipes are retrofitted to the insertion holes, and the outer peripheral surface of the tube plate and the inner peripheral surface of the tank are closely attached to both ends of the tank. A tube plate is fixed and a pair of end plates covering both ends of the tank are detachably attached to the tank so that the heat exchange pipe and the end plate are disassembled from the tank. The flow dividing plate that changes the flow of the low-temperature compressed air after cooling and dehumidification supplied into the tank is fixed in advance, and a number of insertion holes through which the heat exchange pipe is inserted are opened in the flow dividing plate. Heat exchange to the tube plate When inserting the pipe for heat, the heat exchange pipe is also inserted into the flow dividing plate to support the side surface of the heat exchange pipe, and the pressure of the compressed air in the tank and the heat exchange pipe are A heat exchanger for dehumidification of large-capacity compressed air, characterized in that the difference from the pressure of compressed air is set within 0.1 KPa .

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