CN209978698U - Tube plate assembly and heat exchanger comprising same - Google Patents

Abstract

A tube plate assembly at least comprises a first tube plate and a second tube plate, wherein at least one first tube hole is formed in the first tube plate, at least one second tube hole is formed in the second tube plate, and the first tube hole can be aligned with the corresponding second tube hole, so that a heat exchange tube of a heat exchanger can penetrate through the first tube hole and the second tube hole to penetrate through the tube plate assembly. Wherein the mutually facing surfaces of the first tube sheet and the second tube sheet are at least partially in contact with each other when mounted together, and wherein a first sealing means is provided between the first tube sheet and the heat exchange tubes and a second sealing means is provided between the second tube sheet and the heat exchange tubes. The tube plate assembly structure improves the sealing performance between the tube plate and the heat exchange tube. A heat exchanger including the tube sheet assembly is also disclosed.

Description

Tube plate assembly and heat exchanger comprising same

Technical Field

The present invention relates to a tube sheet assembly for a heat exchanger, and further to a heat exchanger including the tube sheet assembly, which is particularly suitable for heat exchange in corrosive fluid environments.

Background

Shell-and-tube heat exchangers are widely used in many industrial fields, and mainly include a shell, at least one heat transfer tube mounted in the shell by, for example, passing an end portion through a tube plate, and two fluids having different temperatures flowing inside and outside the heat transfer tube, respectively, where the fluid inside the heat transfer tube is referred to as "tube-side fluid" and the fluid outside the heat transfer tube is referred to as "shell-side fluid". Heat exchange between the tube-side fluid and the shell-side fluid is achieved through the outer wall of the heat transfer tube.

The current conventional connection between the heat transfer tubes and the tube sheet is by means of a threaded connection, which is used in particular in corrosive fluid environments, wherein the heat transfer tubes are made of corrosion resistant materials such as ceramics, graphite, etc. In addition, in the assembling process, the heat exchange tube and the tube plate need to be connected and fixed by using structures such as a threaded sleeve and a sealing ring. However, during use, the seal ring may wear and, at the same time, corrosive fluids may corrode the seal ring, such that after a period of time, the seal ring may fail, resulting in corrosive fluids flowing to the shell side, contaminating the shell side fluid.

In order to solve the problem of the pollution of corrosive fluid to shell pass fluid, a double-tube plate structure is also provided in the prior art. However, the double tube sheet structure still has some problems in use. In particular, for the double tube plate structure, the sealing ring may still fail due to corrosion of corrosive fluid or other reasons, and in order to replace and repair the failed sealing ring, the two-layer tube plate structure needs to be completely removed, which results in a large repair workload.

Therefore, in the field of heat exchangers, particularly for heat exchangers operating in corrosive fluid environments, there is a need for an improved structure that can improve the sealing between the tube sheet and the heat exchange tube, and further, can achieve at least one of the objectives of reducing the maintenance workload, increasing the operating pressure of the heat exchanger, and the like.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a make for at least one in the problem that solves above prior art existence, its purpose provides the tube sheet subassembly for the heat exchanger of an improved structure, and it can improve the leakproofness between tube sheet and the heat exchange tube.

The utility model discloses a tube sheet subassembly is used for heat exchanger, this tube sheet subassembly includes first tube sheet and second tube sheet at least, be provided with at least one first tube hole in the first tube sheet, be provided with at least one second tube hole in the second tube sheet, first tube hole can be aimed at with the second tube hole that corresponds, so that heat exchanger's heat exchange tube can pass first tube hole and second tube hole and wear to establish on the tube sheet subassembly, wherein, when installing together, the surface that faces mutually of first tube sheet and second tube sheet contacts mutually at least partially, and, be provided with first sealing device between first tube sheet and heat exchange tube, and be provided with second sealing device between second tube sheet and heat exchange tube.

In the structure, the sealing devices are respectively arranged between the first pipe hole and the heat exchange pipe and between the second pipe hole and the heat exchange pipe, each sealing device can independently play a sealing role, and even if one sealing device fails, the sealing device only needs to be maintained and replaced, and other sealing devices cannot be influenced. Therefore, the sealing performance between the tube plate and the heat exchange tube is improved, and the leakage risk of the heat exchanger is reduced.

In a specific implementation, the first tube hole is a counterbore, and comprises a first part with a smaller diameter and a second part with a larger diameter, a step is formed between the first part and the second part, and the first sealing device is arranged between the first tube plate and the heat exchange tube at the second part of the first tube hole.

In addition, the second tube hole may also be a counterbore including a first portion having a smaller diameter and a second portion having a larger diameter, a step being formed between the first portion and the second portion of the second tube hole, and a second sealing means being provided between the second tube plate and the heat exchange tube at the second portion of the second tube hole.

With respect to the specific construction of the sealing means, in a preferred embodiment, the first sealing means comprises: the first sealing ring is abutted against the step part in the first pipe hole; and the first fixing piece is inserted between the inner wall of the first pipe hole and the outer wall of the heat exchange pipe from the second part of the first pipe hole and fixes the first sealing ring in place.

Likewise, the second sealing device may also include: the second sealing ring is abutted to the step part in the second pipe hole; and a second fixing member inserted between an inner wall of the second pipe hole and an outer wall of the heat exchange pipe from the second portion of the second pipe hole, and fixing the second sealing ring in place.

Further, the first fixing piece is a first threaded sleeve, wherein an internal thread is formed in the inner wall of the second portion of the first pipe hole, and an external thread matched with the internal thread of the second portion of the first pipe hole is formed on the outer wall of the first threaded sleeve.

The second fixing member may also be a second barrel, wherein an internal thread is formed in an inner wall of the second portion of the second pipe hole, and an external thread matching the internal thread of the second portion of the second pipe hole is formed on an outer wall of the second barrel.

Preferably, a first gap is formed between the first fixing member and the outer wall of the heat exchange tube; and/or a second gap is formed between the second fixing member and the outer wall of the heat exchange tube.

Through the arrangement of the gap, the friction resistance between each tube plate and the heat exchange tube can be reduced. Thus, if stress is generated in the heat exchange tube due to a difference in thermal expansion coefficient during heat exchange, the heat exchange tube can slide with respect to the respective tube sheets without being broken by the stress and without causing failure of the sealing device.

Preferably, the thickness of the first portion of the first pipe aperture is equal to or greater than the thickness of the sealing ring. The connection strength of the first pipe hole can be guaranteed through the arrangement, and materials can be saved to a certain extent.

Preferably, a connecting groove is arranged between the first tube plate and the second tube plate, and the connecting groove is used for connecting the first tube holes together and/or connecting the second tube holes together, especially connecting the first tube holes together; and a discharge passage is formed in the first tube plate or the second tube plate, communicates with the connection groove, and is open to the outside of the tube plate assembly. One exemplary configuration of the vent passage is a vent slot. Of course, the discharge passage may also take other forms, such as a discharge hole extending to the outside through the first or second tube sheet, or the like.

Wherein the connection groove may be formed by providing a groove on a surface of the first tube sheet facing the second tube sheet, may be formed by providing a groove on a surface of the second tube sheet facing the first tube sheet, or may be formed collectively by providing grooves aligned with each other on the surfaces of the first tube sheet and the second tube sheet facing each other at the same time.

By providing the connecting groove and the discharge passage, when a leak occurs, the leaked fluid can flow to the outside via the connecting groove and the discharge passage, so that an operator can observe from the outside or detect whether the seal device leaks by a detection instrument provided at an outlet of the discharge passage.

Preferably, the width of the connecting groove and/or the discharging groove is more than or equal to 0.5 mm; and/or the depth of the connecting groove and/or the discharge groove is more than or equal to 0.5 mm. Preferably, the width is 1 to 5mm and the depth is 1 to 5 mm.

Therefore, the leakage fluid can be smoothly discharged, the reduction of the heat exchange efficiency can be avoided, and the manufacturing cost can not be obviously increased.

Preferably, in the mounted state, a circumferential gap is formed between one end of the second sealing device facing the first tube plate and a surface of the second tube plate facing the first tube plate, the circumferential gap surrounding the heat exchange tubes and communicating with the connecting groove. In this way, fluid in the connection tank may be allowed to flow around the heat exchange tube into the discharge channel.

In the above-mentioned specific structure in which the second sealing device includes the second seal ring and the second fixing member, the circumferential gap is formed between an end portion of the second fixing member facing away from the second seal ring and a surface of the second tube plate facing the first tube plate.

In addition, the first tube sheet and the second tube sheet are preferably in close contact with each other, so that the overall strength thereof can be improved. Specifically, the remaining portions of the mutually facing surfaces of the first tube sheet and the second tube sheet are in contact with each other, except for the portions provided with the first and second tube holes, the connecting groove, and the circumferential gap described above, to increase the contact area and improve the strength thereof.

Preferably, the end of the first thread insert close to the first sealing ring does not comprise an external thread; and/or the end of the second thread insert near the second sealing ring does not comprise an external thread. Such a configuration may optimize compression of the first/second seal rings. The first sealing ring and the second sealing ring can be compressed by pressing, so that the heat exchange tube is clamped, and a sealing effect is realized between the tube plate and the heat exchange tube.

Further, the outer periphery of the first tube sheet is formed with at least one first screw hole, and the outer periphery of the second tube sheet is formed with at least one second screw hole, each first screw hole being alignable with each second screw hole to allow a bolt to pass therethrough, wherein the first screw hole is preferably a counter bore, a bolt is inserted from the second tube sheet side and projected from the first tube sheet side and threadedly engaged with a nut, and the nut is received in the first screw hole. In this way, it is ensured that the first and second tube sheets are pressed together.

The utility model discloses an among the tube sheet subassembly, first tube sheet is made by corrosion-resistant material, and the second tube sheet is made by metal material. The heat exchange tube is made of silicon carbide materials. Such a structure may be used, for example, in environments where corrosive fluids are used, such as in pipe-side applications.

In alternative arrangements, the first pipe aperture may be of other shapes, for example an annular recess may be formed in the first pipe aperture, the recess receiving the first sealing ring therein. In this configuration, the first nut may be omitted, that is, the first sealing means may be constituted by a first seal ring. Further, in this structure, the above-described structure of the connection groove, the discharge passage, the circumferential gap, and the like may also be provided.

The utility model discloses still relate to a heat exchanger, this heat exchanger includes casing, tube side head and sets up as above between casing and tube side head the tube sheet subassembly.

The tube side end socket and the shell of the heat exchanger can be respectively provided with a connecting flange so as to be respectively connected with one of the first tube plate and the second tube plate of the tube plate assembly. Alternatively, the tube-side head may be integrally formed with one of the first and second tube sheets, and/or the shell may be integrally formed with the other of the first and second tube sheets.

Drawings

In the drawings:

figure 1a shows an end view of a heat exchanger of a first embodiment of the invention.

FIG. 1b shows a partial cross-sectional view of the heat exchanger taken along line A-A in FIG. 1 a.

Fig. 2 shows a partial enlargement of the section I in fig. 1 b.

Fig. 3a shows a front view of the tube-side tube sheet of the heat exchanger of the first embodiment.

FIG. 3B shows a cross-sectional view of the tube-side tubesheet taken along line B-B of FIG. 3 a.

Fig. 4 shows a front view of a modified structure of the tube-side tube sheet.

Figure 5a shows an end view of a heat exchanger of a second embodiment of the invention.

Fig. 5b shows a partial cross-sectional view of the heat exchanger taken along line C-C in fig. 5 a.

Fig. 6 shows a partial cross-sectional view of a heat exchanger according to a third embodiment of the present invention.

Fig. 7 shows a partial enlarged view of a portion II in fig. 6.

Detailed Description

In order to facilitate understanding of the present invention, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that only the preferred embodiment of the invention has been shown in the drawings and is not to be considered limiting of its scope. Various obvious modifications, variations and equivalents of the embodiments of the invention described in the following can be made by those skilled in the art on the basis of the embodiments shown in the drawings, and without contradiction, the technical features in the different embodiments described below can be combined at will, and these are all within the scope of the invention.

< first embodiment >

Fig. 1a to 4 show a first embodiment of the present invention. Fig. 1a shows an end view of a heat exchanger 100 according to a first embodiment of the invention, and fig. 1b shows a partial cross-sectional view taken along line a-a in fig. 1 a.

As shown in fig. 1a and 1b, the heat exchanger 100 includes a shell (or can also be referred to as a tube) 110, a tube-side head 120, and a tube sheet assembly 130 located between the shell 110 and the tube-side head 120.

A shell-side connection pipe 111 is arranged on the shell 110, one end of the shell-side connection pipe 111 is connected to the shell 110, and a shell-side connection pipe flange 112 is optionally arranged on the other end for connecting with an external pipeline. Shell-side fluid can flow into the interior of shell 110 via shell-side tap 111.

The tube-side end enclosure 120 is provided with a tube-side adapter 121, similar to the shell-side adapter 111, one end of the tube-side adapter 121 is connected to the tube-side end enclosure 120, and the other end is optionally provided with a tube-side adapter flange 122 for connecting with an external pipeline. The tube-side fluid can flow into the tube-side header 120 via the tube-side connection tubes 121 and into the heat exchange tubes 140 secured to the tube sheet assembly 130.

In the configuration shown in fig. 1b, the tube sheet assembly 130 includes two tube sheets, a tube-side tube sheet (or first tube sheet) 131 and a shell-side tube sheet (or second tube sheet) 132. A plurality of screw holes 135 are formed in the circumferential direction of the tube-side tube sheet 131 and the shell-side tube sheet 132, respectively (see fig. 3a and 3 b). When installed, corresponding screw holes 135 in the tube-side and shell- side tube sheets 131, 132 are aligned with one another, allowing bolts 136 to pass through the screw holes 135, thereby connecting the tube-side and shell- side tube sheets 131, 132 together.

It should be noted that fig. 1b only shows a partial cross-sectional view of one end side (right side) of the heat exchanger 100, and the heat exchanger 100 further includes a portion on the left side of the figure, that is, a tube plate assembly 130 and a tube-side end plate 120 of the same structure are also connected to the end of the shell 110 on the left side in fig. 1 b.

Further, a tube-side head flange 123 is formed on the end of the tube-side head 120 that contacts the tube-side tube sheet 131, and screw holes capable of aligning with the screw holes 135 are also formed on the tube-side head flange 123, and bolts 136 may pass through the screw holes 135, thereby connecting the tube sheet assembly 130 to the tube-side head 120. As shown in fig. 1b, a nut 137 is attached to the end of the bolt 136 near the tube-side end cap 120 to achieve the final fixation.

Preferably, the screw holes 135 on the shell-side tube sheet 13 may be counter-bored so that a tube sheet nut 138 may be provided at its side facing the tube-side head 120 to help ensure at least partial contact between the facing surfaces of the tube-side tube sheet 131 and the shell-side tube sheet 132. Furthermore, by providing the tube sheet nut 138, the tube-side tube sheet 131 and the shell-side tube sheet 132 can be secured together to form the complete tube sheet assembly 130, and then the tube sheet assembly 130 can be attached to the tube-side head 120 as a unit. When the tube-side end socket 120 needs to be cleaned, the tube-side end socket 120 can be detached without separating the tube-side tube plate 131 from the shell-side tube plate 132, so that the operation is more convenient.

The specific structure of the tube sheet assembly 130 will be further described below in conjunction with fig. 2. Fig. 2 is an enlarged partial view of a portion I in fig. 1b, from which it can be seen that the tube-side tube sheet 131 is formed with at least one, preferably a plurality of first tube holes 133, and the shell-side tube sheet 132 is formed with at least one, preferably a plurality of second tube holes 134, wherein each of the first tube holes 133 corresponds to a respective one of the second tube holes 134, for example, the number of first tube holes 133 is the same as the number of second tube holes 134, and when installed, the corresponding first tube holes 133 and second tube holes 134 are aligned with each other, thereby allowing the heat exchange tubes 140 to pass through and be fixed in the first tube holes 133 and second tube holes 134. In the case of having a plurality of first duct apertures 133 and second duct apertures 134, the heat exchanger 100 correspondingly also includes a plurality of heat exchange tubes 140. Three first tube holes 133 and three second tube holes 134 are visible in the cross-sectional view of the heat exchanger 100 shown in fig. 1b, but for clarity, only the heat exchange tubes 140 are shown inserted into the middle first tube holes 133 and second tube holes 134, but it will be appreciated by those skilled in the art that, in use, corresponding heat exchange tubes 140 are also inserted into the upper and lower first tube holes 133 and second tube holes 134.

For each heat exchange tube 140, a first sealing means is provided between the heat exchange tube 140 and the first tube hole 133. In the preferred construction shown in FIG. 2, the first tube bore 133 is in the form of a counterbore that includes a first portion 1331 having a smaller diameter and a second portion 1332 having a larger diameter. The first portion 1331 has a diameter substantially the same as the outer diameter of the corresponding heat exchange tube 140, preferably slightly larger than the outer diameter of the heat exchange tube 140, to allow the heat exchange tube 140 to be smoothly inserted into the first tube hole 133. The second portion 1332 of the first tube hole 133 has a diameter greater than the outer diameter of the heat exchange tube 140 so that a first sealing means can be disposed between the heat exchange tube 140 and the first tube hole 133 at the second portion 1332.

In the configuration shown in fig. 2, the first sealing means includes a tube-side thread insert (or first thread insert) 151 and a first sealing ring 152. The first seal ring 152 is preferably an O-ring and is carried by a step between the first portion 1331 and the second portion 1332 of the first tube bore 133 and is held in place by the tube side nut 151 and is preferably compressed by the action of the tube side nut 151 so that the tube side nut 151 acts as a first retainer for retaining the first seal ring 152.

In a preferred construction, the inner wall of the second portion 1332 of the first tube bore 133 having the larger diameter is internally threaded and the outer wall of the tube-side insert 151 is correspondingly externally threaded. By the fit between the internal and external threads, the tube side insert 151 is positioned between the inner wall of the second portion 1332 and the outer wall of the heat exchange tube 140 and is able to abut and further compress the first seal ring 152.

In the preferred construction shown in fig. 2, it can be seen that a gap is also left between the inner wall of the tube-side thread insert 151 and the outer wall of the heat exchange tube 140. In other words, the heat exchange tube 140 is not in contact with the tube-side thread insert 151, and the heat exchange tube 140 is fixed to the tube-side tube sheet 131 only by contact with the first portion 1331 of the first tube hole 133. In this way, when the heat exchange tube 140 axially slides with respect to the tube-side tube plate 131, frictional resistance therebetween is small, thereby reducing the risk of the heat exchange tube being broken due to a reduction in the sealing effect during heat exchange or stress generated on the heat exchange tube 140 due to the difference in the thermal expansion coefficients of the shell 110 and the heat exchange tube 140.

It is further preferable that the thickness of the first portion 1331 of the first tube hole 133, i.e., the distance from the step between the first portion 1331 and the second portion 1332 to the shell-side surface of the tube-side tube plate 131, be greater than the thickness of the first seal ring 152, or the difference between the inner diameter and the outer diameter of the first seal ring 152. In this way, the connection strength can still be ensured while saving material as much as possible.

Further, the end of the tube-side thread insert 151 near the first seal ring 152 preferably does not include an external thread. Such an arrangement enables better compression of the first seal ring 152 to effect a seal.

Similar to the first sealing means, the second sealing means is disposed between the heat exchange tubes 140 and the second tube holes 134 of the shell-side tube sheet 132. Wherein the second tube bore 134 is also preferably counter-bored and includes a first portion 1341 having a smaller diameter and a second portion 1342 having a larger diameter. A second portion 1342 of the second tube aperture 134 has a diameter greater than the outer diameter of the heat exchange tube 140 so that a second sealing means can be disposed between the heat exchange tube 140 and the second tube aperture 134 at the second portion 1342.

The second sealing means comprises a shell-side thread insert 153 and a second sealing ring 154, preferably an O-ring. The second sealing ring 154 is supported by a step between the first portion 1341 and the second portion 1342 of the second pipe hole 134 and is fixed in place by a shell-side thread insert (or second thread insert) 153, i.e., the shell-side thread insert 153 serves as a second fixing member for fixing the second sealing ring 153.

In a preferred construction, the inner wall of the second portion 1342 of the first tube bore 134 is also internally threaded and the outer wall of the shell-side nut 153 is correspondingly externally threaded to threadably position the tube-side nut 151 between the inner wall of the second portion 1342 and the outer wall of the heat exchange tube 140 and to be able to abut and further compress the second seal ring 154.

A certain gap may also be left between the inner wall of the shell-side thread insert 153 and the outer wall of the heat exchange tube 140, so that when the heat exchange tube 140 axially slides relative to the shell-side tube plate 132, the frictional resistance between the two is small, thereby reducing the risk of the heat exchange tube being cracked due to the reduced sealing effect during the heat exchange process or stress generated on the heat exchange tube 140 caused by the difference in thermal expansion coefficients of the shell 110 and the heat exchange tube 140.

Further, the thickness of the first portion 1341 of the second tube hole 134, i.e., the distance from the step between the first portion 1341 and the second portion 1342 to the shell-side surface of the shell-side tube plate 132 is smaller than the thickness of the second seal ring 154.

It is also preferable that no external thread be included at the end of the shell-side thread insert 153 adjacent to the second seal ring 154. Such an arrangement enables better compression of second seal ring 154 to effect a seal. Here, the length of the end of the second sealing ring 154 not comprising the external thread is more than 0.5mm, preferably in the range of 1-5 mm. And the outer diameter of the end portion of the tube side thread insert 151 excluding the external thread is equal to, and preferably smaller than, the base diameter of the external thread on the tube side thread insert 151, thereby ensuring that the end portion does not interfere with the internal thread on the inner wall of the second portion 1332 of the first tube hole 133.

As further shown in fig. 2, a connecting groove 161 and a discharge groove 162 are provided between the tube-side tube sheet 131 and the shell-side tube sheet 132. The connecting groove 161 and the discharge groove 162 may be formed by providing a groove on at least one of the mutually facing surfaces of the tube-side tube sheet 131 and the shell-side tube sheet 132. The structure of the connecting groove 161 and the discharge groove 162 is more clearly shown in fig. 3a and 3b, in which the tube-side tube sheet 131 is taken as an example. As can be seen in fig. 3a and 3b, a plurality of first tube holes 133, specifically, a central first tube hole 133 formed at the center of the tube-side tube plate 131 and six first tube holes 133 arranged around the central first tube hole 133, are formed in the tube-side tube plate 131. A coupling groove 161 is provided between the first duct holes 133 to communicate each first duct hole 133 with at least one of the other first duct holes 133.

In the preferred embodiment shown in fig. 2, six first pipe holes 133 are circumferentially arranged around the central first pipe hole 133, and correspondingly, a part of the coupling groove 161 may be formed as a closed circle, a polygon, or the like, with the central first pipe hole 133 as a center, along with the circumferentially arranged six first pipe holes 133.

All the connecting grooves 161 eventually converge to a discharge passage that connects the connecting grooves 161 to the outside of the tube-side tube sheet 131 and the shell-side tube sheet 132. One particular form of vent passage is, for example, the vent slot 162 shown in fig. 3a and 3 b. When any one of the first and second sealing devices leaks, the leaked tube-side fluid and/or shell-side fluid flows into the connecting groove 161 and flows out through the discharge groove 162. In this way, it is possible to observe from the outside of the heat exchanger 100 or to detect whether the first sealing means and the second sealing means have leaked by a detection instrument provided at the outlet of the discharge passage.

Further, the fluid leaking out may be detected, the type of the fluid flowing out may be determined, and it may be determined which of the first sealing device and the second sealing device has leaked, based on the detected type of the fluid. The heat exchanger 100 may itself be provided with a detection device (not shown) for detecting the type of fluid leaking out.

Of course, the discharge passage may be in other forms, for example, a discharge hole extending from the mutually facing surfaces of the tube-side tube sheet 131 and the shell-side tube sheet 132, which hole may extend in either one of the tube-side tube sheet 131 and the shell-side tube sheet 132 and eventually to the outside of the tube-side tube sheet 131 and the shell-side tube sheet 132. The extending direction and form of the vent hole may be any as long as it is ensured that the leakage fluid, which is converged into the vent hole from the connection groove 161, can flow to the outside.

The size of the connecting groove 161 and the discharge groove 162 is set in consideration of ensuring smooth discharge of the leak fluid, and at the same time, it is necessary to ensure effective contact between the tube-side tube sheet 131 and the shell-side tube sheet 132 to ensure heat exchange efficiency between the tube-side fluid and the shell-side fluid on both sides of the tube sheet assembly 130. Further, it is necessary to ensure that the leak fluid can be smoothly discharged with respect to the depth of the connection groove 161 or the discharge groove 162, but if the depth is too large, the amount of machining increases, and the thickness requirements for the tube-side tube plate 131 and the shell-side tube plate 132 increase, leading to an increase in cost. In view of these factors, in the present invention, the width of the connection groove 161 and the discharge groove 162 is set to be greater than 0.5mm, preferably between 1-5mm, and the depth of the connection groove 161 and the discharge groove 162 is set to be greater than 0.5mm, preferably between 1-5 mm. By setting the dimensions of the depths of the connection groove 161 and the discharge groove 162 within the above numerical ranges, the smoothness of the flow of the leaking fluid can be significantly optimized while the manufacturing cost can be controlled within a reasonable range.

In addition, the inventors of the present invention have noticed that the heat exchange pipe 140 inserted in the first and second pipe holes 133 and 134 has a function of blocking the communication between the connection groove 161 and the discharge groove 162. To overcome this blocking effect of the heat exchange tubes 140, one method is to provide circumferential grooves on the surface of the tube-side tube sheet 131 facing the shell-side tube sheet 132 at positions around the heat exchange tubes 140. This increases the processing cost and may affect the strength of the portion of the tube-side tube sheet 131 corresponding to the tube-side thread insert 151.

Preferably, in the present invention, the longitudinal length of the second sealing means is set to be smaller than the longitudinal length of the second portion 1342 of the second pipe hole 134. In fig. 2, the sum of the cross-sectional diameter of second sealing ring 154 (or the height of second sealing ring 154) and the longitudinal length of shell-side threaded sleeve 153 is shown to be smaller than the longitudinal length of second portion 1342. Thus, after being mounted in place, a circumferential gap 163 is formed between the end of the shell-side thread insert 153 facing the tube-side tube sheet 131 and the surface of the shell-side tube sheet 132 facing the tube-side tube sheet 131, the circumferential gap 163 communicating with the connection groove 161, thereby allowing the leaked fluid to flow downward bypassing the heat exchange tubes 140. The size of the circumferential gap is set to be greater than or equal to 0.5mm, preferably in the range of 0.5-3 mm. This size of the circumferential gap allows to significantly optimize the smoothness of the flow of the leakage fluid while keeping the machining costs within a reasonable range.

In addition, in the case where the second sealing means takes other structural forms, in general, this circumferential gap 163 is formed between the end of the second sealing means that faces the tube-side tube sheet 131 and the surface of the shell-side tube sheet 132 that faces the tube-side tube sheet 131.

In the present invention, the tube sheet assembly 130 includes two tube sheets, i.e., a tube-side tube sheet 131 and a shell-side tube sheet 132, as described above, and in an assembled state, the tube-side tube sheet 131 and the shell-side tube sheet 132 are in contact with each other, thereby serving as a support for each other. Thus, in the present invention, when used in an environment with corrosive fluids, the tube-side tube sheet 131, the heat exchange tube 140, and the tube-side end plate 120 may be made of a corrosion-resistant material for the corrosive fluids to flow through, while the shell-side tube sheet 132 may be made of a high-strength material such as steel as the case 110, thereby providing the tube sheet assembly 130 with overall structural strength. Thus, even in the corrosive fluid application environment, the heat exchanger 100 of the present invention can still bear high working pressure, for example, even under the corrosive fluid application environment of high pressure of 2 MPa-10 MPa, the heat exchanger 100 of the present invention can still work normally.

In order to enhance the supporting effect of the shell-side tube sheet 132 on the tube-side tube sheet 131, it is preferable to arrange the shell-side tube sheet 132 and the tube-side tube sheet 131 so that most of their mutually facing surfaces are in contact with each other. In other words, it is preferable that the remaining portions of the tube-side tube sheet 131 and the shell-side tube sheet 132 contact each other, except for the portions mentioned above where the first tube hole 133, the second tube hole 134, the connecting groove 161, the discharge groove 162, the screw holes 135, and the like are featured. Also, the tube-side tube plate 131 and the shell-side tube plate 132 are brought into closer contact by the arrangement of the nut 137, thereby improving the strength thereof.

With respect to the specific materials forming the above components, the heat exchange tube 140 may preferably be made of silicon carbide (SiC), the tube-side header 120 may be made of a corrosion-resistant material such as teflon, or a teflon layer may be coated on the inner surface of the tube-side header 120 that may come into contact with corrosive fluids. For the tube sheet assembly 130, the material for forming the tube-side tube sheet 131 includes, for example, polytetrafluoroethylene, ceramics such as silicon carbide, or the like, or may have a polytetrafluoroethylene layer, a ceramic coating, or the like on the outer layer, and preferably, the tube-side tube sheet 131 is made of polytetrafluoroethylene. The material for forming the shell-side tube sheet 132 includes, for example, a high-strength metal material such as stainless steel, titanium alloy, carbon steel, or the like. The tube side thread insert 151 is made of a corrosion-resistant material, such as polytetrafluoroethylene. The material of the shell-side thread insert 153 is preferably a metal material having a certain strength, such as stainless steel or carbon steel.

Further, in addition to the case of two tube sheets, the tube sheet assembly 130 of the present invention may also include more than two tube sheets, which is also within the scope of the present invention. For example, one more tube sheet may be added on the side of the shell-side tube sheet 132 facing the shell 110, one more tube sheet may be added on the side of the first tube holes 133 facing the tube-side head 120, and one more tube sheet may be added between the tube-side tube sheet 131 and the shell-side tube sheet 132. Further, a connecting groove 161, a discharge groove 162, and the like may be provided between the tube plates in the manner described above.

In addition, seven first tube holes 133 are included in the tube-side tube sheet 131 shown in fig. 3a, and correspondingly, seven second tube holes 134 are also included in the shell-side tube sheet 132. In addition to the configuration shown in fig. 3a, the tube-side tube sheet 131 and the shell-side tube sheet 132 may include other numbers and arrangements of first tube holes 133 and second tube holes 134, respectively. For example, in the modified structure shown in fig. 4, 19 first tube holes 133 are formed in the tube-side tube sheet 131, and are arranged to include one central first tube hole 133 and two layers of first tube holes 133 arranged circumferentially around the central first tube hole 133, an intermediate layer including six first tube holes 133 and an outer layer including twelve first tube holes 133, respectively.

Correspondingly, as shown in fig. 4, the connecting groove 161 also includes two inner and outer portions in a closed ring shape (circular or polygonal).

In the structure shown in fig. 1b, the shell-side tube sheet 132 is integrally formed on the shell 110, thereby simultaneously functioning as a connecting flange of the shell 110. Accordingly, the tube-side tube plate 131 may also be integrally formed on the tube-side head 120, so that the tube-side head flange 123 may be omitted. On the other hand, the shell-side tube sheet 132 may also be separate from the shell body 110, with a connecting flange being additionally formed on the shell body 110, as described below.

< second embodiment >

Fig. 5a and 5b show a second embodiment of the invention. Wherein the same feature portions as those of the first embodiment are denoted by like reference numerals, and the following disclosure mainly describes features different from those of the first embodiment without detailed description of the same features. Features described in the first embodiment are equally applicable to the second embodiment, unless otherwise stated.

Fig. 5a shows an end view of a heat exchanger 200 according to a second embodiment of the invention, and fig. 5b shows a partial cross-sectional view taken along line C-C in fig. 5 a.

As with the heat exchanger 100 of the first embodiment, the heat exchanger 200 includes a shell 210, a tube-side head 220, and a tube sheet assembly 230 disposed between the shell 210 and the tube-side head 220. A shell flange 213 is formed at the end of the shell 210 in contact with the tube sheet assembly 230 for connection with the tube sheet assembly 230, and a tube-side head flange 223 is formed at the end of the tube-side head 220 in contact with the tube sheet assembly 230 for connection of the tube-side head 220 with the tube sheet assembly 230.

As such, in the second embodiment, the tube sheet assembly 230 may be completely separated from the shell 210 and the tube-side head 220, thereby facilitating maintenance service of the heat exchanger 200.

< third embodiment >

Fig. 6 and 7 show a third embodiment of the present invention. Wherein the same feature portions as those of the first and second embodiments are denoted by like reference numerals, and the following disclosure mainly describes features different from those of the first and second embodiments without detailed description of the same features. Features described in the first and second embodiments are equally applicable to the third embodiment, unless described to the contrary.

Fig. 6 shows a partial cross-sectional view of a heat exchanger 300 according to a third embodiment of the present invention, and fig. 7 shows a partial enlarged view of a portion II in fig. 6.

As shown in the enlarged view of fig. 7, the first tube hole 333 in the tube-side tube plate 331 is not formed in a counter bored form as in the first and second embodiments, but an annular groove 335 is formed in the inner wall of the first tube hole 333, the annular groove 335 being sized to receive the first seal ring 352. Thus, in the third embodiment, the first sealing means comprises only the first sealing ring 352, and the tube-side thread insert of the previous two embodiments is omitted.

The second tube apertures 334 of the shell-side tube sheet 332 in the third embodiment are again in the form of counterbores in which the second seal rings 354 and shell-side bosses 353 are received. It is contemplated that in the third embodiment, the second tube hole 334 may also be formed in the same shape as the first tube hole 333, so that the shell-side thread insert 353 may be omitted. However, the structure shown in fig. 7 is preferable because it can be facilitated to form the circumferential gap 163 on the surface of the shell-side tube sheet 332 that faces the tube-side tube sheet 331.

Claims (19)

1. A tube sheet assembly for a heat exchanger, wherein the tube sheet assembly comprises at least a first tube sheet having at least one first tube aperture provided therein and a second tube sheet having at least one second tube aperture provided therein, the first tube aperture being alignable with a corresponding second tube aperture to enable heat exchange tubes of the heat exchanger to be passed through the tube sheet assembly through the first and second tube apertures,

when mounted together, the mutually facing surfaces of the first tube sheet and the second tube sheet are at least partially in contact with each other, and a first sealing means is provided between the first tube sheet and the heat exchange tubes and a second sealing means is provided between the second tube sheet and the heat exchange tubes.

2. The tube sheet assembly of claim 1, wherein the first tube aperture is a counterbore having a first portion with a smaller diameter and a second portion with a larger diameter, a step being formed between the first portion and the second portion, the first sealing means being disposed between the first tube sheet and the heat exchange tubes at the second portion of the first tube aperture; and/or

The second tube hole is a counterbore including a first portion having a smaller diameter and a second portion having a larger diameter, a step is formed between the first portion and the second portion of the second tube hole, and the second sealing means is disposed between the second tube plate and the heat exchange tube at the second portion of the second tube hole.

3. The tube sheet assembly of claim 2, wherein the first sealing means comprises: a first seal ring abutting the step in the first tube bore; and a first fixing member inserted between an inner wall of the first pipe hole and an outer wall of the heat exchange pipe from the second portion of the first pipe hole, and fixing the first sealing ring in place; and/or

The second sealing device includes: a second seal ring abutting the step in the second tube bore; and a second fixing member inserted between an inner wall of the second pipe hole and an outer wall of the heat exchange pipe from the second portion of the second pipe hole, and fixing the second sealing ring in place.

4. The tube sheet assembly of claim 3, wherein the first fastener is a first threaded insert, wherein the inner wall of the second portion of the first tube aperture has an internal thread formed therein and wherein the outer wall of the first threaded insert has an external thread formed thereon that mates with the internal thread of the second portion of the first tube aperture; and/or

The second fixing piece is a second threaded sleeve, wherein an internal thread is formed in the inner wall of the second portion of the second pipe hole, and an external thread matched with the internal thread of the second portion of the second pipe hole is formed on the outer wall of the second threaded sleeve.

5. The tube sheet assembly of claim 3, wherein the first portion of the first tube bore has a thickness equal to or greater than a thickness of the seal ring.

6. The tube sheet assembly of claim 1, wherein a connection groove is provided between the first tube sheet and the second tube sheet, the connection groove communicating each of the first tube apertures together and/or each of the second tube apertures together, and

a discharge passage is formed in the first tube sheet or the second tube sheet, the discharge passage communicating with the connection groove and opening to the outside of the tube sheet assembly.

7. The tube sheet assembly of claim 6, wherein the connection groove is formed on a surface of the first tube sheet facing the second tube sheet and/or a surface of the second tube sheet facing the first tube sheet.

8. The tube sheet assembly of claim 6 or 7, wherein the vent passage is a vent slot.

9. The tube sheet assembly of claim 8, wherein the width of the attachment groove and/or the drain groove is 0.5mm or greater; and/or

The depth of the connecting groove and/or the discharge groove is more than or equal to 0.5 mm.

10. The tube sheet assembly of claim 9, wherein the width of the attachment slots and/or the drain slots is 1-5 mm; and/or

The depth of the connecting groove and/or the discharge groove is 1-5 mm.

11. The tube sheet assembly of claim 6 or 7, wherein in an installed state, a circumferential gap is formed between an end of the second sealing means facing the first tube sheet and a surface of the second tube sheet facing the first tube sheet, the circumferential gap surrounding the heat exchange tubes and communicating with the connection groove.

12. The tube sheet assembly of claim 11, wherein the circumferential gap has a dimension greater than or equal to 0.5 mm.

13. The tube sheet assembly of claim 11, wherein the circumferential gap has a dimension in the range of 0.5-3 mm.

14. The tube sheet assembly of claim 11, wherein remaining portions of the facing surfaces of the first and second tube sheets are in contact with each other except for portions where the first and second tube apertures, the connecting groove, and the circumferential gap are provided.

15. The tube sheet assembly of claim 3,

a connecting groove is provided between the first tube sheet and the second tube sheet, the connecting groove communicating the respective first tube holes together and/or the respective second tube holes together, and

a discharge passage is formed in the first tube plate or the second tube plate, communicates with the connection groove, and is open to the outside of the tube plate assembly;

in an installed state, a circumferential gap is formed between the end part of the second fixing piece, which is opposite to the second sealing ring, and the surface of the second tube plate, which faces the first tube plate, and the circumferential gap surrounds the heat exchange tube and is communicated with the connecting groove.

16. The tube sheet assembly of claim 15, wherein the circumferential gap has a dimension greater than or equal to 0.5 mm.

17. The tube sheet assembly of claim 15, wherein the circumferential gap has a dimension in the range of 0.5mm to 3 mm.

18. The tube sheet assembly of claim 1, wherein the inner wall of the first tube bore has an annular groove formed therein, the first sealing means comprising a first sealing ring received in the annular groove; and/or

The periphery of the first tube plate is formed with at least one first screw hole, the periphery of the second tube plate is formed with at least one second screw hole, each first screw hole can be aligned with each second screw hole to allow a bolt to pass through, wherein the first screw holes are counter bores, the bolts are inserted from one side of the second tube plate and extend out from one side of the first tube plate and are in threaded fit with nuts, and the nuts are accommodated in the first screw holes; and/or

The first tube plate is made of a corrosion-resistant material, and the second tube plate is made of a metal material; and/or

The heat exchange tube is made of silicon carbide materials.

19. A heat exchanger comprising a shell, a tube-side head, and the tube sheet assembly of any one of claims 1-18 disposed between the shell and the tube-side head.

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