JP2007057134A - Shell-and-tube heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shell-and-tube heat exchanger that prevents, to a high degree, the mixing of fluid flowing in a shell and fluid flowing in heat transfer tubes, without adopting a double tube plate method. <P>SOLUTION: The shell-and-tube heat exchanger includes at least a shell, tube plates, and heat transfer tubes. The shell is a hollow jacket, and has the tube plates secured at each of its ends. There are a plurality of heat transfer tubes, each of which is suspended as at least one end thereof is inserted into one of a plurality of openings formed in at least one of the tube plates. The openings are formed as holes leading to the outside of the tube plates. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multitubular heat exchanger that is suitably used for heat exchange of fluids such as gases (including mixed gases) and liquids (including solutions and dispersions), particularly liquids. More specifically, the present invention relates to a shell-and-tube heat exchanger that can highly prevent mixing of liquid flowing in a can body and liquid flowing in a heat transfer tube.

  Conventionally, a multi-tube heat exchanger has been known as an apparatus for efficiently exchanging heat of fluid. This multi-tube heat exchanger has a structure in which a plurality of small-diameter heat transfer tubes called tubes are installed between two supports called tube plates in a large-diameter cylindrical can body called a shell. For this reason, it is also called a shell and tube heat exchanger.

  In this multi-tube heat exchanger, a heat exchange fluid is caused to flow in the heat transfer tube, and a high-temperature or low-temperature heat medium or refrigerant (hereinafter simply referred to as a heat medium) is caused to flow in the can body. The heat exchange was performed indirectly between the fluid and the heat medium via the tube wall. Such heat exchange is performed through a plurality of small-diameter heat transfer tubes. As a result, the contact area with the heat medium is increased and the exchange efficiency is extremely excellent. For this reason, this kind of multi-tubular heat exchanger has been used as a means for heating or cooling beverages even during heat treatment of beverages for the purpose of sterilization or the like.

  By the way, in such a multi-tube heat exchanger, it is required that the fluid flowing in the heat transfer tube and the fluid (heat medium) flowing in the can body are not mixed. For this reason, various methods have been proposed to satisfy this requirement, and a so-called double tube plate method in which the tube plate has a double structure is one of such proposals (for example, Patent Document 1).

  In this double tube sheet type multi-tube heat exchanger, when the double structure tube plate is a first tube plate and a second tube plate, a gap is formed between the first tube plate and the second tube plate. If the gap is made to communicate with the outside, the intrusion of the heating medium or fluid can be easily detected from the outside through the gap, and the detection of the mixture of both can be easily performed. Is possible. In addition, since this void portion is connected to the outside and is in a reduced pressure state compared to its peripheral portion, the heat medium or fluid that has entered the region can selectively enter the void portion and be discharged to the outside. Therefore, it is possible to prevent the mixing of both of them with considerable efficiency. Furthermore, it is possible to prevent abnormal overheating of the tube sheet portion by introducing cooling air or the like into the gap portion from the outside.

Thus, the double tube sheet type multi-tube heat exchanger has various merits, but when it is formed at both ends of the can body, a total of four tube sheets are required and the structure is complicated. Therefore, an extremely high manufacturing cost is required, and the economic burden has been a problem.
JP 2003-130579 A

  The present invention has been made in view of the current situation as described above, and the object of the present invention is to employ a fluid flowing in a can body and a fluid flowing in a heat transfer tube without adopting a double tube sheet method. An object of the present invention is to provide a multi-tubular heat exchanger that is highly prevented from mixing.

  The present invention is a multi-tube heat exchanger having at least a can body, a tube plate, and a heat transfer tube, the can body being an outer envelope of a hollow structure, at both ends thereof Each of the tube plates is attached, and there are a plurality of the heat transfer tubes, and at least one end portion of each is inserted into one of the openings formed in the at least one tube plate. The opening relates to a multi-tube heat exchanger characterized in that a hole communicating with the outside of the tube sheet is formed.

  Here, it is preferable that the hole communicates with the hole formed in the other opening to communicate with the outside of the tube sheet. The holes preferably communicate with the outside of the tube sheet by communicating with each other so as to have a linear positional relationship with the holes formed in the other openings.

  Further, the tube sheet is formed with at least one groove so as to go around the inner wall surface forming the opening, and the hole is formed so as to be connected to one of the grooves. preferable.

  Moreover, it is preferable that the said heat exchanger tube is expanded in the said opening part, and it is preferable that the seal welding is carried out in one end surface of the said opening part.

  The multitubular heat exchanger preferably includes a detection device that detects fluid discharged from the hole to the outside, and hot water, water vapor, or an inert gas is supplied to the hole. It can also be made.

  The multi-tube heat exchanger according to the present invention has a configuration as described above, and highly prevents the fluid flowing in the can body and the fluid flowing in the heat transfer tube from being mixed despite the low manufacturing cost. It is possible to do that.

  Hereinafter, the present invention will be described in more detail. In the following description of the embodiments, the description is made with reference to the drawings. In the drawings of the present application, the same reference numerals denote the same or corresponding parts.

<Multi-tube heat exchanger>
A schematic cross-sectional view of the multitubular heat exchanger of the present invention is shown in FIG. As shown in FIG. 1, the multi-tube heat exchanger 100 of the present invention includes at least a can body 1, tube sheets 2 and 21, and a heat transfer tube 3. In FIG. 1, the tube plates 2 and 21 look like double tube plates separated into two parts by holes 46, but this only looks like that in the cross-sectional configuration, and each reality is It is a single tube sheet.

  Here, the said can body 1 becomes a jacket of a hollow structure, Comprising: The said tube sheets 2 and 21 are each attached to the both ends. The two tube sheets 2 and 21 are attached so as to face each other when there is no bent portion in the longitudinal direction of the can body 1. Further, a plurality of the heat transfer tubes 3 exist, and at least one end portion of each of the heat transfer tubes 3 is installed by being inserted into one of the openings formed in the at least one tube plate. More preferably, as shown in FIG. 1, such a plurality of heat transfer tubes 3 are inserted into one of the openings 25 formed at the tube plates 2 and 21 at both ends thereof. It will be built by. The opening 25 is formed with a hole 46 communicating with the outside of the tube plates 2 and 21.

  The multi-tube heat exchanger 100 according to the present invention has the above-described basic configuration, so that fluids having different temperatures flow in the can body 1 and the heat transfer tube 3. The heat exchange is performed indirectly between these fluids via the.

  In the following description, a mode in which both ends of each heat transfer tube are installed by being inserted into a plurality of openings formed in each of the two tube plates will be described as an example. However, the present invention is not limited to this, and only one end of the heat transfer tube is inserted into the opening of any one of the two tube plates. Such a hole is formed, and the other end is connected to the other tube plate by a different connection method, and the above-described hole is not formed. Even in such an embodiment, the above-described effects of the present invention are shown.

<Can body>
The can body 1 is also referred to as a shell, and serves as a shell of a hollow structure and serves as a main body of a multi-tube heat exchanger. Usually, the shape has a cylindrical shape with an outer diameter of 30 mm to 700 mm and a length of 2 m to 6 m. However, the outer diameter and length are not limited to such a range, and the cross-sectional shape is not limited to such a circular shape. The cross-sectional shape can be a polygonal shape such as a quadrangle or a hexagon, or an elliptical shape, and is not limited at all.

  Such a can body 1 has two tube plates 2 and 21 (described later) attached to both ends thereof, and a plurality of heat transfer tubes 3 are supported. The material of the can body 1 is not particularly limited, but is preferably stainless steel.

  The can body 1 is usually provided with a nozzle 15, and has a structure in which a fluid can be supplied into the can body 1 or discharged from the can body 1. For example, as shown in FIG. 1, two such nozzles 15 may be formed in the vicinity of both ends of the can body 1. That is, of the two nozzles, the fluid is supplied into the can body 1 by the one nozzle, and the fluid is discharged by the other nozzle.

  Each of such nozzles is preferably arranged in the vicinity of both ends of the can body 1 and particularly close to each of the tube sheets 2 and 21. Although the tube plates 2 and 21 are arranged further to the end side than the position where each nozzle is arranged in the longitudinal direction of the can body, there is a certain distance between each nozzle and these tube plates. This is because when the space is formed, the fluid flowing in the can body becomes trapped in that portion.

  In addition, the can body 1 can be of an integral structure that is integrated with itself, but for example, as shown in FIG. 1, a portion that includes one of the nozzles is divided into short tubes. It can also be a formula structure. In this way, by dividing the portion including one of the nozzles into short tubes, the tube sheet can be easily observed and cleaned, and dirt and defects can be effectively prevented. It is also preferable from the viewpoint.

  In addition, the part divided into the short tube in this way includes one of the nozzles. If the joint 5 is formed between one of the nozzles and the tube plate, the inside of the can body is formed along with the formation of the joint 5. This is because an unnecessary space is generated, and the fluid in the can body is prevented from standing in this space.

  On the other hand, a joint portion having a ferrule-structured triangular groove is used for the joint portion 5 between the portion divided into a short tube and the can body as described above, and an O-ring 55 (synthetic rubber or the like) is used as a packing in the joint portion. It is preferable to use a ring-shaped sealing material made of an elastic body.

<Tube sheet>
Since the tube sheet of the present invention is attached to both end portions of the can body 1, at least two tube sheets are arranged. That is, as shown in FIG. 1, two tube sheets 2 and 21 are attached to both ends of the can body 1. This attachment method is not particularly limited. For example, it can be fixedly attached by the joint portion 5 as in the tube plate 2 shown in FIG. 1 and can be attached in a movable state as in the tube plate 21. . Usually, a tube plate fixedly attached is called a fixed tube plate, and a tube plate attached in a movable state is called a floating tube plate. The two tube plates 2 and 21 may be fixed tube plates, or one of them may be a floating tube plate. In addition, when setting it as a fixed tube sheet, it can also integrate with the can body 1 by welding etc. other than the case where it fixes in the state which can be removed by the junction part 5 shown in FIG. However, in consideration of the cleanability in the can body 1 and the like, it is preferable to fix it in a removable state. In this regard, it is preferable to adopt a ferrule structure for the joint 5 as in the joint 5 of the can body 1.

  The floating tube plate (tube plate 21) has, for example, a first groove portion 27 and a second groove portion 28 along the outer periphery of each end portion in the thickness direction of the tube plate, and the first groove portion 27 and the second groove portion. By inserting the O-ring 55 into each of the main body 28 and the inner wall 10 in the can body 1, the O-ring 55 can be moved in any direction.

  Such tube sheets 2, 21 have a plurality of openings 25, and thus have an effect of laying (supporting) the heat transfer tubes 3 by inserting both ends of the heat transfer tubes 3 described later into the openings 25. Is. In the case of such a fixed tube plate, the outer shape of the tube plates 2 and 21 is substantially equal to the outer shape of the can body 1, and the thickness thereof is 20 mm to 100 mm. In the case of the floating tube plate, the outer diameter is substantially equal to the inner diameter (about 30 to 700 mm) of the can body 1, and the thickness is 20 to 100 mm. The material of the tube plates 2 and 21 is not particularly limited, but is preferably stainless steel.

<Heat transfer tube>
The heat transfer tube 3 is also called a tube, and a plurality of the heat transfer tubes 3 exist in the can body 1. The number is more preferably 4 to 120.

  The shape of the heat transfer tube 3 is preferably a cylindrical shape having an outer diameter of 10 mm to 40 mm, and its length is substantially the same as the length of the can body 1. Moreover, the cross-sectional shape is not limited to a circular shape like the can body 1, but can be a polygonal shape such as a square or a hexagon, or an elliptical shape. Not limited. However, since the heat transfer tube 3 is inserted into the opening 25 of the tube plates 2 and 21, the cross-sectional shape thereof must match the shape of the opening, and the shape of the opening is usually easy to process. Since the heat transfer tube 3 has a circular shape, the cross-sectional shape of the heat transfer tube 3 is preferably circular. The material of the heat transfer tube 3 is not particularly limited, but is preferably stainless steel.

  There are a plurality of such heat transfer tubes 3 as described above, and both end portions thereof are inserted into one of the openings 25 formed in the two tube plates 2 and 21 respectively. Is installed (supported).

<Openings and holes>
Each of the plurality of openings formed in the tube sheet of the present invention is characterized in that a hole communicating with the outside of the tube sheet is formed. Such a hole exhibits the same effect as a gap formed between a pair of conventional tube plates, and is used for the heat medium or fluid flowing through the can body or the heat transfer tube. It shows the effect of detecting intrusion and preventing the mixing of both at a high level.

  That is, when the hole communicates with the outside of the tube plate (usually in the atmosphere), the intrusion of the heating medium or fluid can be easily detected from the outside through the hole, and both of them are mixed. The function as a monitor for preventing the above is shown. Moreover, this hole not only shows such a monitoring effect, but also leads to the outside of the tube sheet, so it is in a reduced pressure state compared to its peripheral part (inside the can body or in the tube sheet). The infiltrated heat transfer medium or fluid does not return to the inside of the can body or heat transfer pipe from this hole again, but is selectively discharged to the outside through the hole. It becomes.

  More specifically, for example, the fluid flows from the side supplying the fluid flowing in the heat transfer tube (usually called the header side, further to the right side of the tube plate 21 in FIG. 1) through the insertion portion of the heat transfer tube. When the fluid enters the inside 21, the fluid is prevented from being mixed with the fluid (usually a heat medium) that is discharged to the outside through the hole 46 and flows in the can body 1. On the other hand, when the fluid flowing in the can body 1 enters the tube plate 21 from the left side of the tube plate 21 in FIG. 1 through the insertion portion of the heat transfer tube, the fluid is discharged to the outside through the hole 46, Mixing with the fluid present on the right side of the tube plate 21 is prevented. Therefore, such a mechanism prevents both the fluid flowing in the can body 1 and the fluid flowing in the heat transfer tube 3 from being mixed. In the present invention, the mixing of both fluids is highly prevented without adopting a tube sheet having a double tube sheet structure, and the manufacturing cost has been extremely reduced.

  Here, such an opening has substantially the same diameter as the outer diameter of the heat transfer tube, and from the viewpoint of easy manufacture, the cross-sectional shape is preferably generally circular, and the heat transfer tube per one tube plate Are formed so as to penetrate the thickness direction of the tube sheet.

  The hole preferably has a diameter of 2 to 4 mm, and the cross-sectional shape is preferably generally circular from the viewpoint of easy manufacture. In addition, as shown in FIG. 2, at least two such holes 46 are formed per one opening, and each hole normally communicates with the holes 46 formed in the other opening 25. This leads to the outside of the tube sheet 2 (usually in the atmosphere).

  Further, as shown in FIG. 2, such holes 46 communicate with each other so as to have a linear positional relationship with the holes 46 formed in the other openings 25, so that they are outside the tube sheet 2. It is preferable to communicate. This is because of manufacturing reasons, and such holes 46 are formed so as to penetrate a plurality (or one) of the openings 25 in a direction parallel to the diameter direction of the tube sheet. In this case, the holes 46 having a linear positional relationship are preferably arranged in a straight line. However, the holes 46 that pass through a certain opening and the other openings (or the same opening) pass through. The case where the holes 46 are not completely aligned is also included.

  On the other hand, the tube sheet 2 has at least one groove 48 formed around the inner wall surface 29 forming the opening as shown in FIG. It is preferable that they are formed so as to be connected. As will be described later, when the heat transfer tube 3 is expanded at the opening 25, the tube wall 31 of the heat transfer tube 3 is in close contact with the inner wall surface 29 so as to enter the groove 48, so that the heat transfer tube and the opening are separated from each other. The connection is more complete. Such a groove 48 has a depth of about 0.1 to 2 mm, preferably a width of about 2 to 7 mm, and preferably two grooves are formed per opening. One of the two is connected to the hole 46, and the other one is not connected to the hole 46 and can be formed mainly for the purpose of improving the connection effect mainly by expanding the tube.

  As described above, the hole 46 communicates with the outside of the tube plate. However, when the tube plate is the floating tube plate (tube plate 21) shown in FIG. 4), the hole 46 is a space 49 formed between the can body 1 and the tube plate 21 as shown in FIG. 4 (that is, the O-ring 55 inserted in the first groove 27 in FIG. 1). , A detection hole 47 formed in the can body 1 through the space 49, which leads to a space 49) surrounded by the O-ring 55 inserted in the second groove portion 28, the tube plate 21, and the can body 1. It is preferable to communicate with the outside. On the other hand, when the tube plate is the fixed tube plate (tube plate 2) shown in FIG. 1 (that is, when the can body 1 is not disposed as an outer cover on the outer periphery of the tube plate 2), FIG. As shown in FIG. 4, the hole 46 directly communicates with the outside.

<Connection of heat transfer tube>
The heat transfer tube 3 is preferably connected to a tube plate by being expanded at the opening. As a result, the connection effect is improved, and the gap 45 formed between the tube wall 31 of the heat transfer tube and the inner wall surface 29 of the tube sheet is reduced as much as possible, and the fluid can be effectively prevented from entering the gap 45. can do.

  In addition, the heat transfer tube 3 has a seal weld 4 on one end surface of the opening (preferably the surface on the header side for supplying or discharging the fluid flowing in the heat transfer tube) as shown in FIG. preferable. Thereby, it is possible to effectively prevent fluid (fluid flowing in the heat transfer tube) from entering between the tube wall 31 of the heat transfer tube and the inner wall surface 29 of the tube plate.

  In addition, as shown in FIG. 3, the protrusion part 26 can be formed in the surface of the opening part by which the said seal welding is not carried out, By welding this protrusion part 26 and the tube wall 31 of a heat exchanger tube, It is also possible to connect the heat transfer tube and the tube sheet.

<Heat exchange method>
As described above, the multi-tube heat exchanger 100 according to the present invention indirectly flows through the tube wall 31 of the heat transfer tube 3 by flowing fluids having different temperatures through the can body 1 and the heat transfer tube 3. In addition, heat exchange is performed between these fluids. In this case, the direction of the fluid flowing in the can body 1 and the direction of the fluid flowing in the heat transfer tube 3 are preferably opposed to each other, but may be parallel. In addition, the fluid in the can body 1 is usually a heat medium, and the fluid in the heat transfer tube 3 is a fluid to be heat exchanged, but is not limited to such a mode. Absent. It is also possible to circulate the fluid flowing in the can body 1 and the fluid flowing in the heat transfer tube 3.

  In addition, although the fluid exchanged using the multi-tubular heat exchanger 100 of the present invention is not particularly limited, for example, milk, milk beverage, fruit juice beverage, coffee, tea, green tea, carbonated beverage, Alcohol, mineral water, energy drinks, soup, sauce, noodle soup and the like, or water for preparation and extraction used in the production process of these beverages can be mentioned.

  In addition, the fluid exchanged using the multitubular heat exchanger 100 of the present invention is not limited to beverages as described above, and liquids such as various liquid medicines (eg eye drops) and various chemicals. Is included. Moreover, this fluid is not restricted only to a liquid, Gas is also contained.

<Others>
As long as the multi-tube heat exchanger 100 of the present invention includes the can body 1, the tube plates 2 and 21, and the heat transfer tube 3 as described above, an arbitrary configuration other than these can be added. Can do. For example, the heat transfer tube 3 may be further supported by an auxiliary support material or the like.

  Further, the multi-tube heat exchanger 100 of the present invention may be provided with a detection device that detects fluid discharged from the hole to the outside, and hot water, water vapor, or an inert gas is provided in the hole. Any of the above may be supplied. As the detection device, a conventionally known means known as a means for detecting a fluid can be adopted without particular limitation. For example, a proximity switch (an object (fluid) approaching the detection surface or an object present in the vicinity ( (Switch that detects the presence or absence of fluid) without mechanical contact), photoelectric switch (switch that detects an object (fluid) blocking the optical path), and electrode (conducting object (fluid) to make the two electrodes conductive) , A switch for detecting the object (fluid). Such a detection device is preferably installed in the vicinity of the outermost surface where the hole communicates with the outside. For example, the periphery of the detection hole 47 in FIG. 4 or the tube plate 2 in which the hole 46 is formed in FIG. It can be installed in the peripheral part of the outermost surface part (when a plurality of holes 46 are formed, it is not always necessary to install them corresponding to all the holes).

  On the other hand, a sterilizing effect in the hole can be imparted by supplying any one of hot water, water vapor, or inert gas to the hole, which can be cited as a preferred embodiment. In this case, it is preferable to prevent the inside of the hole from being in a pressurized state from the peripheral region by supplying them. In addition, it is preferable that the temperature of hot water, water vapor | steam, or an inert gas shall be about 100 degreeC or more, and nitrogen, argon, etc. can be mentioned as an inert gas.

  In addition, the multi-tube heat exchanger 100 of the present invention is connected to a plurality of multi-tube heat exchangers via the nozzle 15 and the tube plates 2 and 21 to construct a multi-stage heat exchange system. You can also.

  Thus, the multitubular heat exchanger 100 of the present invention can be used in combination with a plurality of multitubular heat exchangers 100 of the present invention, and also includes a heating device, a cooling device, a heat medium supply device, and a refrigerant supply device. Alternatively, these can be used in combination with a pump.

  Of course, the multi-tube heat exchanger 100 of the present invention can be used in combination with other pipes. For example, the fluid flowing in the heat transfer tube 3 can be supplied or discharged by connecting a pipe having the same inner diameter as the can body 1 to the tube plates 2 and 21 side. Further, by connecting a pipe having the same inner diameter as the nozzle 15 to the nozzle 15, the fluid flowing in the can body 1 can be supplied or discharged.

  As described above, the embodiments of the present invention have been described, but it is also planned from the beginning to appropriately combine the configurations of the above-described embodiments.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic sectional drawing of the multitubular heat exchanger of this invention. FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. 1 (however, heat transfer tubes are omitted). It is the schematic sectional drawing which expanded the insertion part to the opening part of a heat exchanger tube. FIG. 4 is a schematic sectional view taken along line IV-IV in FIG. 1 (however, heat transfer tubes are omitted).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Can body, 10 Inner wall, 15 Nozzle, 2,21 Tube plate, 25 Opening part, 26 Protrusion part, 27 1st groove part, 28 2nd groove part, 29 Inner wall surface, 3 Heat exchanger tube, 31 Tube wall, 4 Seal welding, 45 voids, 46 holes, 47 detection holes, 48 grooves, 49 spaces, 5 joints, 55 O-ring, 100 multi-tube heat exchanger.

Claims (8)

A multi-tubular heat exchanger comprising at least a can body, a tube sheet, and a heat transfer tube,
The can body is an envelope of a hollow structure, and the tube plates are attached to both ends thereof,
There are a plurality of the heat transfer tubes, and at least one end portion of each of the heat transfer tubes is installed by being inserted into one of the openings formed in the at least one tube plate,
The opening is formed with a hole that communicates with the outside of the tube plate.   The multi-tube heat exchanger according to claim 1, wherein the hole communicates with the hole formed in the other opening to communicate with the outside of the tube sheet.   3. The multi-tube according to claim 2, wherein the holes communicate with each other so as to have a linear positional relationship with other holes formed in the other opening portion, thereby communicating with the outside of the tube sheet. Type heat exchanger.   The tube sheet is formed with at least one groove so as to go around the inner wall surface forming the opening, and the hole is formed so as to be connected to one of the grooves. The multitubular heat exchanger according to any one of claims 1 to 3.   The multi-tube heat exchanger according to any one of claims 1 to 4, wherein the heat transfer tube is expanded at the opening.   The multi-tube heat exchanger according to any one of claims 1 to 5, wherein the heat transfer tube is sealed by welding at one end face of the opening.   The multitubular heat exchanger according to any one of claims 1 to 6, wherein the multitubular heat exchanger includes a detection device that detects a fluid discharged from the hole to the outside. .   The multitubular heat exchanger according to any one of claims 1 to 7, wherein the multitubular heat exchanger is supplied with hot water, water vapor, or an inert gas into the holes. .

Images