Combined wound tube heat exchanger

Abstract

A combined type wound tube heat exchanger comprises a shell pass cylinder, the axial direction of the shell pass cylinder is the first direction, the radial direction of the shell pass cylinder is the second direction, and the first end and the second end of the shell pass cylinder are each provided with a shell pass connecting pipe for a shell pass medium to pass through; the first heat exchange tubes are arranged in the shell pass barrel in the first direction; first tube plates are arranged at the positions, corresponding to the two ends of the first heat exchange tube, of the shell pass barrel; the plurality of second heat exchange tubes are arranged in the first end part of the shell pass barrel along a second direction; the two second tube plates are oppositely arranged on the two radial sides of the first end of the shell pass barrel so as to support the two ends of the second heat exchange tube. The shell pass heat exchange efficiency is improved through the space at the end of the shell pass barrel. Meanwhile, due to the fact that the second heat exchange pipes are arranged in the second direction, the second heat exchange pipes can play a role in flow equalization, fluid distribution of shell pass media at the end of the shell pass barrel is improved, and then heat exchange dead angles are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of heat exchangers, and in particular relates to a combined coiled-tube heat exchanger. Background Art

[0002] The existing coiled tube heat exchanger, such as the structure disclosed in the Chinese utility model patent No. 201420655906.2 "New Multi-stream Heat Exchanger" (authorization announcement No. CN204359171U), includes a shell, heat exchange tubes arranged in the shell, and upper and lower tube plates arranged at both ends of the shell. The two ends of the heat exchange tubes are respectively limited on the upper and lower tube plates. The shell is provided with a shell side inlet and a shell side outlet connected to the inner cavity of the shell; and there are multiple groups of heat exchange tubes, and the part of each heat exchange tube group located between the upper and lower tube plates is spirally coiled along the axial direction of the shell. Corresponding to each heat exchange tube group, the shell is provided with a tube side outlet and a tube side inlet that are connected to multiple heat exchange tube groups. When in use, different tube side media can be introduced into each heat exchange tube group, and heat is exchanged with the fluid in the shell at the same time, thereby improving the heat exchange efficiency.

[0003] Another example is the Chinese utility model patent "A Heat Exchanger Group" (authorization announcement number CN206755943U) with patent number 201720622189.7, which includes a first heat exchanger and a second heat exchanger. The first heat exchanger includes a first shell and a first heat exchange tube installed in the first shell through a first tube sheet, and is provided with a first shell side inlet and a first shell side outlet connected to the inner cavity of the first shell, and a first tube side inlet and a first tube side outlet connected to the first heat exchange tube; the second heat exchanger includes a second shell and a second heat exchange tube installed in the second shell through a second tube sheet, and is provided with a second shell side inlet and a second shell side outlet connected to the inner cavity of the second shell, and a second tube side inlet and a second tube side outlet connected to the second heat exchange tube; the first heat exchanger and the second heat exchanger are distributed in a straight line, and a short connection structure that maintains the same straight line distribution as the first and second heat exchangers is connected between the first tube side outlet and the second tube side inlet. The heat exchanger group has the advantages of low cost, small footprint, small pressure drop loss, and small heat loss.

[0004] The existing coiled-tube heat exchangers often have the problem of uneven distribution of the shell-side medium inside the shell-side cylinder and the heat exchange effect needs to be improved. Therefore, the existing technology mostly improves the fluid distribution by setting components such as flow equalizers inside the shell-side cylinder, thereby improving the heat exchange efficiency. However, setting up flow equalizers will increase the cost.

[0005] Moreover, for the multi-stream heat exchanger or heat exchanger group mentioned in the above patent, the flow path of the tube-side medium in each group of heat exchange tubes is close, resulting in a close temperature difference before and after the heat exchange of each tube-side medium. However, under certain working conditions, the temperatures to be heated or cooled of the tube-side medium are different, such as the temperature difference before and after the heat exchange of the first tube-side medium needs to be greater than the temperature difference before and after the heat exchange of the second tube-side medium. The existing heat exchanger cannot meet the requirements under the above working conditions. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a combined coiled-tube heat exchanger in view of the current status of the prior art to improve the heat exchange efficiency.

[0007] The technical solution adopted by the present invention to solve the above technical problems is: a combined coiled-tube heat exchanger, comprising:

[0008] The shell-side cylinder, the axial direction of which is the first direction and the radial direction of which is the second direction, is provided with a shell-side pipe for the shell-side medium to pass through at the first end and the second end of the shell-side cylinder;

[0009] A plurality of first heat exchange tubes are arranged in the shell-side cylinder along a first direction;

[0010] A first tube sheet supporting the first heat exchange tube is provided at positions on the shell side cylinder corresponding to both ends of the first heat exchange tube;

[0011] It is characterized by also including:

[0012] A plurality of second heat exchange tubes are arranged in the first end of the shell-side cylinder along the second direction;

[0013] The two second tube sheets are arranged oppositely at two radial sides of the first end of the shell-side cylinder to support two ends of the second heat exchange tube.

[0014] In the prior art, the heat exchange efficiency at the end of the shell-side cylinder is low. The design of the second heat exchange tube in the present invention can overcome this technical problem and use the space at the end of the shell-side cylinder to improve the shell-side heat exchange efficiency. And because the second heat exchange tube is arranged along the second direction, the flow path of the tube-side medium in the second heat exchange is shorter, so that the temperature difference of the tube-side medium before and after heat exchange through the second heat exchange tube can be better controlled, and the temperature difference is different from the temperature difference of the medium in the first heat exchange tube before and after heat exchange. At the same time, because the second heat exchange tube is arranged along the second direction, the second heat exchange tube can play a role in equalizing flow (no need to set up an additional equalizing plate), improve the fluid distribution of the shell-side medium at the end of the shell-side cylinder (distribution is more uniform), and thus reduce the heat exchange dead angle.

[0015] Preferably, it also includes a central tube, which is arranged in the shell-side cylinder along the first direction, and the plurality of first heat exchange tubes are at least partially spirally wound around the outer circumference of the central tube; the plurality of second heat exchange tubes are arranged from the inside to the outside on the outer circumference of the central tube.

[0016] Preferably, the interior of the central tube is hollow;

[0017] The first heat exchange tube has two parts along the length direction, namely a first part and a second part which are connected to each other. The first part is spirally wound around the outer circumference of the central tube, and the second part is penetrated into the central tube. The end of the first part and the end of the second part are respectively supported on their corresponding first tube sheets.

[0018] Preferably, the shell-side cylinder is vertically arranged with the first end facing upward and the second end facing downward, wherein one first tube sheet is arranged at the top of the shell-side cylinder and connected to the upper end of the center cylinder, and the other first tube sheet is arranged on the side wall of the upper part of the shell-side cylinder and below the second tube sheet, and the lower end of the center cylinder is a free end with an opening facing downward, so that the second part of the first heat exchange tube can pass through the free end and be arranged in the center cylinder.

[0019] Furthermore, the shell-side cylinder includes a vertically arranged straight cylinder, an upper head detachably arranged at the upper port of the straight cylinder, and a lower head arranged at the lower port of the straight cylinder. The second heat exchange tube is arranged in the upper head, and the two first tube sheets and the two second tube sheets are arranged in the upper head. The upper head, the central tube connected to the upper head, and the first heat exchange tube and the second heat exchange tube as a whole (referred to as the core body) are arranged to be able to move upward and detach from the straight cylinder. In this way, the heat exchanger is detachable. When a leak occurs in the heat exchange tube and needs to be checked for leaks, it may cause a long downtime. When the detachable structure of the present invention is adopted, the heat exchanger can be equipped with a core body, and the core body can be replaced in a short time as needed.

[0020] Furthermore, the second heat exchange tubes are arranged in a circle with a small upper end and a large lower end, so as to match the hemispherical shape of the upper head, so that the second heat exchange tubes can effectively utilize the space in the hemispherical upper head.

[0021] In order to improve the stability of the detachable structure, preferably, the first part of the first heat exchange tube has a spiral section spirally wound around the outer periphery of the central tube, and a first straight tube section located below the spiral section and extending vertically;

[0022] An annular support structure is provided at the lower end of the central tube, and the support structure is sleeved on the outer circumference of the central tube. The support structure is provided with a through hole for the first straight tube section of each first heat exchange tube to pass through, and the inner wall surface of the straight tube body is provided with a flange for supporting the support structure.

[0023] Preferably, the upper surface of the flange is provided with a telescopic member that can be extended up and down, and the support structure is placed on the telescopic member, so that the flange can always support the support structure. The telescopic member can be a spring, a bellows, etc. extending up and down.

[0024] Preferably, the support structure comprises:

[0025] An inner ring and an outer ring are arranged one inside and one outside, the inner ring is sleeved on the outer periphery of the lower end of the central tube and connected to the central tube, the outer peripheral surface of the inner ring is spaced opposite to the inner peripheral surface of the outer ring to form an annular cavity that passes through from top to bottom; the outer ring is formed by a plurality of first unit bars arranged in a circle along the circumferential direction, the ends of two adjacent first unit bars are spaced opposite to each other to form a gap for the first straight tube section of the first heat exchange tube to pass through; and the outer ring is supported on the flange;

[0026] A plurality of support bars extending inwardly and outwardly are arranged in the annular cavity at intervals along the circumferential direction, and the outer end of each support bar is connected to the central part of the first unit bar corresponding to each other, and the inner end of each support bar is connected to the corresponding inner ring, so as to divide the annular cavity into a plurality of independent spaces along the circumferential direction, and the independent spaces are the above-mentioned perforations, and each independent space has a corresponding gap;

[0027] The first straight tube sections of the plurality of first heat exchange tubes are divided into a plurality of groups and are respectively arranged in the corresponding independent spaces.

[0028] In this way, the first heat exchange tube can be divided into several strands, and the first straight tube section of each first heat exchange tube passes through the corresponding gaps in sequence and is constrained in an independent space, which is easy to operate.

[0029] And the first heat exchange tube entering the independent space can be distributed on both sides of the gap and close to the corresponding support bars. At this time, the first heat exchange tube located in the independent space does not affect the first heat exchange tube behind it to enter the independent space through the gap, and the first heat exchange tube distributed on both sides of the gap can obtain better restraint effect under the action of the corresponding support bars and the first unit bars.

[0030] Preferably, the inner ring is formed by a plurality of second unit bars arranged in a circle along the circumferential direction, the ends of two adjacent second unit bars are opposite and connected, and the central portion of each second unit bar is connected to the inner end of the corresponding support bar.

[0031] Preferably, the outer end and the inner end of each support bar are connected to the corresponding first unit bar and second unit bar to form an integral part. The support structure of the present invention can be obtained by assembling several integral parts having support bars, first unit bars and second unit bars.

[0032] Preferably, the outer ring or / and the support bar are provided with a plurality of first through holes extending in the up-down direction at intervals. The design of the first through holes can ensure the flow area of ​​the shell-side medium, and the support structure with the first through holes can act as a distribution plate to ensure uniform distribution of the shell-side medium.

[0033] Furthermore, a roller capable of rolling along the inner wall of the straight cylinder is provided on the outer circumferential surface of the outer ring at a position avoiding the gap. When disassembling, the roller can roll along the inner wall of the straight cylinder, thereby facilitating disassembly and assembly.

[0034] Preferably, the first heat exchange tubes passing through each independent space are divided into two groups and are respectively close to the corresponding support bars and distributed on both sides of the corresponding gap. The first heat exchange tubes distributed on both sides of the gap do not affect the first heat exchange tubes behind passing through the gap into the independent space, and the first heat exchange tubes distributed on both sides of the gap can obtain better restraint under the action of the corresponding support bars and the first unit bars.

[0035] Furthermore, the upper head and the straight cylinder are detachably connected via a flange and flange bolts.

[0036] In each of the above schemes, preferably, the first heat exchange tube spirally wound around the outer circumference of the central tube and the second heat exchange tube are arranged along the length direction of the central tube.

[0037] Also preferably, the end of the first heat exchange tube spirally wound around the outer periphery of the central tube is a second straight tube section extending along the first direction and surrounding the outside of the central tube;

[0038] The plurality of second heat exchange tubes are arranged on the periphery of the second straight tube section.

[0039] Furthermore, it also includes a support tube, which is sleeved on the outer circumference of the second straight pipe section along the circumferential direction and fixed relative to the first tube sheet for supporting the end of the second straight pipe section, and a plurality of second through holes are spaced apart on the tube wall of the support tube;

[0040] The plurality of second heat exchange tubes are arranged on the periphery of the support tube.

[0041] The support tube can constrain the second straight tube section to prevent the second straight tube section from shaking during heat exchange, and at the same time the support tube can support the second heat exchange tube, and the through holes on the support tube can allow the shell side medium to flow.

[0042] Furthermore, the second heat exchange tubes in the inner and outer adjacent layers and the second heat exchange tubes in the innermost layer and the support tube are restrained together by gaskets, and each gasket extends along the first direction.

[0043] Furthermore, the plurality of second heat exchange tubes are divided into two groups and are respectively arranged on the outer circumference of the central tube in a C-shaped manner with the C-shaped openings facing each other to surround the central tube as a whole.

[0044] Compared with the prior art, the advantages of the present invention are: in the prior art, the heat exchange efficiency at the end of the shell-side cylinder is low. The design of the second heat exchange tube in the present invention can overcome this technical problem and use the space at the end of the shell-side cylinder to improve the shell-side heat exchange efficiency. And because the second heat exchange tube is arranged along the second direction, the flow path of the tube-side medium in the second heat exchange is shorter, so that the temperature difference of the tube-side medium before and after heat exchange through the second heat exchange tube can be better controlled, and the temperature difference is different from the temperature difference of the medium in the first heat exchange tube before and after heat exchange. At the same time, because the second heat exchange tube is arranged along the second direction, the second heat exchange tube can play a role in equalizing flow (no need to set up an additional equalizing plate), improve the fluid distribution of the shell-side medium at the end of the shell-side cylinder (distribution is more uniform), and thus reduce the heat exchange dead angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0046] Figure 2 for Figure 1 Enlarged view of part A in the middle;

[0047] Figure 3 for Figure 1 Partial structural section view;

[0048] Figure 4 for Figure 1 A top view of the local structure;

[0049] Figure 5 for Figure 3 Enlarged view of the left part of the middle section;

[0050] Figure 6 This is a schematic diagram of the structure of the cushion strip in the first embodiment of the invention;

[0051] Figure 7 This is a schematic structural diagram of a support structure according to Embodiment 1 of the present invention;

[0052] Figure 8 This is a schematic structural diagram of an integrated component constituting a support structure according to Embodiment 1 of the present invention;

[0053] Fig. 9 This is a schematic structural diagram of a support structure constraining a heat exchange tube according to a first embodiment of the present invention;

[0054] Fig.10 for Fig. 9 Enlarged view of middle part B;

[0055] Fig.11 It is a partial cross-sectional view between the cushion strip and the second heat exchange tube in the second embodiment of the invention;

[0056] Fig.12This is a schematic structural diagram of a support structure constraining a heat exchange tube according to a second embodiment of the invention;

[0057] Fig.13 It is a partial structural diagram of the third embodiment of the present invention;

[0058] Fig.14 This is a schematic diagram of the structure of the support tube in the third embodiment of the present invention;

[0059] Fig.15 for Fig.13 Partial structural section view. DETAILED DESCRIPTION

[0060] The present invention is further described in detail below with reference to the accompanying drawings.

[0061] like Figures 1 to 10 As shown, a preferred embodiment 1 of a combined coiled-tube heat exchanger of the present invention is shown, wherein the combined coiled-tube heat exchanger comprises a shell-side cylinder 1, a plurality of first heat exchange tubes 2, a central cylinder 3, a first tube sheet 4, a plurality of second heat exchange tubes 6, a second tube sheet 7 and a gasket 9.

[0062] The shell-side cylinder 1 is arranged vertically (i.e., the first direction described in the claims and the specification of the present invention) with the first end 11 facing upward and the second end 12 facing downward. The shell-side cylinder 1 includes a vertically arranged straight cylinder 101, an upper head 102 arranged at the upper end of the straight cylinder 101, and a lower head arranged at the lower end of the straight cylinder 101. The lower head and the upper head 102 are both provided with a shell-side pipe 103 for the shell-side medium to pass through. The upper head 102 is detachably connected to the straight cylinder 101, specifically, it is detachably connected through the flange 5 and the flange bolts 51, so that the upper head 102 can be separated from the straight cylinder 101.

[0063] There are three first tube sheets 4 , one of which is disposed at the top of the upper head 102 , and the other two first tube sheets 4 are disposed on the side walls at both sides of the upper head 102 .

[0064] There are two second tube sheets 7 , which are respectively arranged on the side walls of both sides of the upper head 102 and are located above the other two first tube sheets 4 .

[0065] The center tube 3 is hollow inside and is vertically arranged in the shell cylinder 1. The upper end of the center tube 3 is opposite to and connected to the first tube sheet 4 located at the top of the upper head 102, and the lower end of the center tube 3 is a free end with an opening facing downward. At the same time, the lower end of the center tube 3 is connected to a support structure 30, such as Figure 1 as well as Figures 7-10 As shown, the support structure 30 includes an inner ring 31 , an outer ring 32 , support bars 33 and rollers 34 .

[0066] The inner ring 31 is sleeved on the outer circumference of the lower end of the center tube 3 and connected to the center tube 3, and the inner ring 31 and the outer ring 32 are arranged coaxially, and the outer circumferential surface of the inner ring 31 is spaced opposite to the inner circumferential surface of the outer ring 32 to form an annular cavity that passes through from top to bottom. The outer ring 32 is formed by N arc-shaped first unit bars 320 arranged in a circle along the circumferential direction, and the ends of two adjacent first unit bars 320 are spaced opposite to each other and form a gap 321 for the first straight tube section 22 of the first heat exchange tube 2 to pass through; the inner ring 31 is formed by N arc-shaped second unit bars 310 arranged in a circle along the circumferential direction, and the ends of two adjacent second unit bars 310 are opposite and connected. Where N is a natural number ≥2. At the same time, a rotatable roller 34 is provided on the outer circumferential surface of the outer ring 32 at a position avoiding the gap 321. The number of rollers 34 matches the number of first unit bars 320, and each roller 34 is respectively provided at the central part of the corresponding first unit bar 320.

[0067] There are N support bars 33, each of which extends inward and outward and is arranged in the annular cavity at intervals along the circumferential direction, and the outer end of each support bar 33 is connected to the central part of the corresponding first unit bar 320, and the inner end of each support bar 33 is connected to the central part of the corresponding second unit bar 310, so that the annular cavity is divided into N independent spaces 300 along the circumferential direction, and each independent space 300 has a corresponding gap 321. In this embodiment, the outer end and the inner end of each support bar 33 are respectively connected to the corresponding first unit bar 320 and the second unit bar 310 to form an integral part, and the N integral parts are combined to form the support structure of this embodiment. In addition, a plurality of first through holes 330 that penetrate in the up and down directions are distributed at intervals on the outer ring 32 and the support bars 33.

[0068] Correspondingly, the inner wall surface of the straight cylinder 101 is provided with a circle of flange 104, and the upper surface of the flange 104 is provided with a spring extending up and down as a telescopic member 105, and the outer ring 32 is placed on the spring. For details, please refer to Figure 1 Thus, when the center tube 3 is separated from the straight cylinder 101 along with the upper head 102, the roller 34 can roll along the inner wall of the straight cylinder 101. When the center tube 3 is installed in the straight cylinder 101, the flange 104 and the spring can stably support the above-mentioned support structure and the center tube 3.

[0069] A plurality of first heat exchange tubes 2 are arranged in the shell-side cylinder 1 along a first direction, and the first heat exchange tube 2 has two parts along the length direction, namely, a first part 2a and a second part 2b which are connected to each other. The first part 2a is arranged around the outer periphery of the central cylinder 3 and has a spiral section 21 spirally wound around the outer periphery of the central cylinder 3, and a first straight tube section 22 located below the spiral section 21 and extending vertically. The first straight tube sections of the plurality of first heat exchange tubes 2 are divided into a plurality of groups and are respectively arranged in the corresponding independent spaces 300; and the first heat exchange tubes 2 arranged in each independent space 300 are divided into two groups and are respectively close to the corresponding support bars 33 and distributed on both sides of the corresponding gap 321. For details, please refer to Fig. 9 , 10 . The second part 2b is passed through the opening at the lower end of the center tube 3 and is arranged in the center tube 3, and the upper ends of the second parts 2b of the plurality of first heat exchange tubes 2 are all supported on the first tube sheet 4 located at the top of the upper head 102, and the upper ends of the first parts 2a of the plurality of first heat exchange tubes 2 are divided into two groups and are respectively supported on the other two corresponding first tube sheets 4 located on the side walls of the upper head 102. The plurality of second heat exchange tubes 6 are arranged from the inside to the outside along the horizontal direction (i.e., the second direction described in the claims and the specification of the present invention) on the periphery of the center tube 3 and in the upper head 102, and are located on the upper side of the first part 2a of the first heat exchange tube 2, and the two ends of the second heat exchange tube 6 are respectively supported on the corresponding second tube sheets 7. In this embodiment, the plurality of second heat exchange tubes 6 are divided into two groups, and are respectively arranged on the radial sides of the center tube 3 in a C-shaped manner with the C-shaped openings facing each other to surround the center tube 3 as a whole. For details, please refer to Figure 4 At the same time, the plurality of second heat exchange tubes 6 arranged on the periphery of the central tube 3 are arranged in a structure with a small upper end and a large lower end, thereby matching the hemispherical shape of the upper head 102. For details, please refer to Figure 3 The cross-sectional portion indicated by the middle arrow B allows the second heat exchange tubes 6 to be distributed in the upper head 102 as much as possible to ensure the heat exchange effect.

[0070] In this embodiment, in order to better constrain the second heat exchange tubes 6, the inner and outer adjacent layers of the second heat exchange tubes 6 and the innermost layer of the second heat exchange tubes 6 and the central tube 3 are constrained together by gaskets 9, each gasket 9 extends vertically and is arranged at intervals along the circumferential direction. Figure 6 As shown, a plurality of semicircular grooves 90 are provided on the gasket strip 9 along the length direction, so as to constrain the corresponding second heat exchange tube 6 therein. At the same time, the inner and outer adjacent gasket strips 9 can be connected by welding (see welding position for details). Figure 6 The part pointed by arrow A in the figure) ensures the stability of the overall structure.

[0071] When in use, the shell-side medium can be input from the shell-side pipe 103 on the upper head 102, exchange heat with the medium in the second heat exchange tube 6, and flow downward through the gaps between the adjacent second heat exchange tubes 6 to exchange heat with the first heat exchange tube 2, and finally output from the shell-side pipe 103 on the lower head of the shell-side cylinder 1. The first tube-side medium to be heat exchanged can enter the first heat exchange tube 2 from the upper end of the second part 2b of the first heat exchange tube 2 and be output from the upper end of the first part 2a. The second part 2b of the first heat exchange tube 2 located in the central tube 3 can participate in the heat exchange or not. When the second part 2b participates in the heat exchange, the existing baffles can be staggered in the first direction in the central tube 3 to guide the shell-side medium, thereby ensuring the heat exchange effect. When the second part 2b does not participate in the heat exchange, a plurality of support plates can be arranged in the central tube 3 along the first direction to support the heat exchange tube.

[0072] When the heat exchange tube needs to be repaired due to leakage, the upper head 102 can be separated from the straight cylinder 101. At this time, the central tube 3 connected to the upper head 102 and the first heat exchange tube 2 and the second heat exchange tube 6 can be separated from the straight cylinder 101 together with the upper head 102.

[0073] Embodiment 2:

[0074] like Fig.11 , 12 As shown in FIG. 1 , a preferred embodiment 2 of a combined coil heat exchanger of the present invention is shown. This embodiment is basically the same as the embodiment 1, except that the second heat exchange tube 6 is constrained by the cooperation between the gasket strip 9 and the tube clamp 91, and the cooperation between the gasket strip 9 and the tube clamp 91 is the same as the prior art, which will not be described in detail here. Fig.12 As shown, the first heat exchange tubes 2 passing through each independent space 300 cover the entire independent space 300 , and when winding, each first heat exchange tube 2 is sequentially arranged in the independent space 300 from the inside to the outside until it covers the entire independent space.

[0075] Embodiment three:

[0076] like Figures 13-15As shown, it is a preferred embodiment 3 of a combined coil-wound heat exchanger of the present invention. This embodiment is basically the same as the embodiment 1, except that there are two first tube sheets 4 in this embodiment, which are respectively arranged on the top of the upper head 102 and the bottom of the lower head. The first heat exchange tube 2 is spirally wound around the outer periphery of the central tube 3 along the first direction as a whole, the upper end of the first heat exchange tube 2 is supported on the first tube sheet 4 on the top of the upper head 102, and the lower end is supported on the first tube sheet 4 on the bottom of the lower head, and the upper end of the first heat exchange tube 2 is a second straight tube section 24 extending vertically and surrounding the outside of the central tube 3, and the outer periphery of the second straight tube section 24 is provided with a support tube 8, which is located in the upper head 102 and fixed relative to the first tube sheet 4 on the top of the upper head 102 by welding, and a plurality of second through holes 80 are distributed at intervals on the tube wall of the support tube 8. In this embodiment, a plurality of second through holes arranged at intervals in the circumferential direction are a group, and there are multiple groups, which are arranged at intervals in the up-down direction. The second through holes between the two adjacent groups are staggered in the vertical direction. For details, please refer to Fig.14 .

[0077] The plurality of second heat exchange tubes 6 are arranged from the inside to the outside of the support tube 8 and the hemispherical head 102 along the horizontal direction (i.e., the second direction in the claims and the specification of the present invention). Similarly, as in the first embodiment, the plurality of second heat exchange tubes 6 arranged on the periphery of the support tube 8 are arranged in a structure with a small upper end and a large lower end, so as to match the shape of the hemispherical head 102. The difference is that in this embodiment, the plurality of second heat exchange tubes 6 are arranged in a truncated cone shape (i.e., a frustum shape) so that the second heat exchange tubes 6 are distributed as much as possible in the hemispherical head 102 to ensure the heat exchange effect. For details, please refer to Fig.15 The cross-sectional portion indicated by arrow C.

[0078] In the specification and claims of the present invention, terms indicating directions, such as "front", "rear", "up", "down", "left", "right", "side", "top", "bottom", etc., are used to describe various exemplary structural parts and elements of the present invention, but these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only used as explanations and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

[0079] The term "vertical" is also used in the specification and claims of the present invention, which means basically along the up and down direction, and is not limited to the vertical direction only, and can also be slightly inclined relative to the vertical direction.

[0080] The term "radial" is also used in the specification and claims of the present invention, which means basically along the inward and outward direction, and is not limited to the radial direction passing through the center of the circle, and can also be slightly deviated from the radial direction.

Claims

1. A combined coiled tube heat exchanger, comprising: The shell-side cylinder (1) has an axial direction as a first direction and a radial direction as a second direction. The first end (11) and the second end (12) of the shell-side cylinder (1) are both provided with a shell-side pipe (103) for the shell-side medium to pass through. A plurality of first heat exchange tubes (2) are arranged in the shell-side cylinder (1) along a first direction; Furthermore, first tube sheets (4) supporting the first heat exchange tube (2) are provided at positions on the shell-side cylinder (1) corresponding to both ends of the first heat exchange tube (2); Features Also included are: A plurality of second heat exchange tubes (6) are arranged in the first end portion (11) of the shell-side cylinder (1) along a second direction; Two second tube sheets (7) are arranged oppositely on radial sides of the first end (11) of the shell-side cylinder (1) to support the two ends of the second heat exchange tube (6).

2. The combined coil heat exchanger according to claim 1, characterized in that: It also includes a central tube (3) arranged in the shell-side cylinder (1) along a first direction, and the plurality of first heat exchange tubes (2) are at least partially spirally wound around the outer periphery of the central tube (3); and the plurality of second heat exchange tubes (6) are arranged on the outer periphery of the central tube (3) from the inside to the outside.

3. The combined coil heat exchanger according to claim 2, characterized in that: The interior of the central tube (3) is hollow; The first heat exchange tube (2) has two parts along the length direction, namely a first part (2a) and a second part (2b) which are connected to each other. The first part (2a) is spirally wound around the outer circumference of the central tube (3), and the second part (2b) is inserted into the central tube (3). The end of the first part (2a) and the end of the second part (2b) are respectively supported on the first tube sheet (4) corresponding to each other.

4. The combined coiled-tube heat exchanger according to claim 3, characterized in that: The shell-side cylinder (1) is vertically arranged with the first end (11) facing upward and the second end (12) facing downward, wherein one first tube sheet (4) is arranged at the top of the shell-side cylinder (1) and connected to the upper end of the center cylinder (3), and the other first tube sheet (4) is arranged on the side wall of the upper part of the shell-side cylinder (1) and below the second tube sheet (7), and the lower end of the center cylinder (3) is a free end with an opening facing downward, so that the second part (2b) of the first heat exchange tube (2) can be passed through the free end and arranged in the center cylinder (3).

5. The combined coiled-tube heat exchanger according to claim 4, characterized in that: The shell-side cylinder (1) comprises a vertically arranged straight cylinder (101), an upper head (102) detachably arranged at the upper end of the straight cylinder (101), and a lower head arranged at the lower end of the straight cylinder (101); the second heat exchange tube (6) is arranged in the upper head (102); two first tube sheets (4) and two second tube sheets (7) are all arranged in the upper head (102); and the upper head (102), a central cylinder (3) connected to the upper head (102), and the first heat exchange tube (2) and the second heat exchange tube (6) are arranged as a whole to be able to move upward and detach from the straight cylinder (101).

6. The combined coiled-tube heat exchanger according to claim 5, characterized in that: After the plurality of second heat exchange tubes (6) are arranged in a circle, the overall structure is small at the upper end and large at the lower end, thereby matching the hemispherical shape of the upper head (102).

7. The combined coiled-tube heat exchanger according to claim 5, characterized in that: The first part (2a) of the first heat exchange tube (2) comprises a spiral section (21) spirally wound around the outer periphery of the central tube (3), and a first straight tube section (22) located below the spiral section (21) and extending vertically; An annular support structure (30) is provided at the lower end of the central tube (3), the support structure (30) is sleeved on the outer circumference of the central tube (3), and the support structure (30) is provided with a through hole for the first straight tube section (22) of each first heat exchange tube (2) to pass through, and the inner wall surface of the straight tube body (101) is provided with a flange (104) for supporting the support structure (30).

8. The combined coiled-tube heat exchanger according to claim 7, characterized in that: A telescopic member (105) capable of extending and retracting upward and downward is provided on the upper surface of the flange (104), and the supporting structure (30) is placed on the telescopic member (105).

9. The combined coiled-tube heat exchanger according to claim 7, characterized in that: The support structure (30) comprises: An inner ring (31) and an outer ring (32) are arranged one inside and one outside, the inner ring (31) is sleeved on the outer circumference of the lower end of the central tube (3) and is connected to the central tube (3), the outer circumferential surface of the inner ring (31) and the inner circumferential surface of the outer ring (32) are spaced opposite to each other to form an annular cavity that passes through from top to bottom; the outer ring (32) is formed by a plurality of first unit bars (320) arranged in a circle along the circumferential direction, the ends of two adjacent first unit bars (320) are spaced opposite to each other to form a gap (321) for the first straight tube section (22) of the first heat exchange tube (2) to pass through; and the outer ring (32) is supported on the flange (104); A plurality of support bars (33) extending inwardly and outwardly are arranged in the annular cavity at intervals along the circumferential direction, and the outer end of each support bar (33) is connected to the central part of the first unit bar (320) corresponding to the respective one, and the inner end of each support bar (33) is connected to the corresponding inner ring (31), thereby dividing the annular cavity into a plurality of independent spaces (300) along the circumferential direction, wherein the independent spaces (300) are the above-mentioned perforations, and each independent space (300) has a corresponding gap (321); The first straight tube sections (22) of the plurality of first heat exchange tubes (2) are divided into a plurality of groups and are respectively arranged in the corresponding independent spaces (300).

10. The combined coiled-tube heat exchanger according to claim 9, characterized in that: The inner ring (31) is formed by a plurality of second unit bars (310) arranged in a circle along the circumferential direction, the ends of two adjacent second unit bars (310) are opposite and connected, and the central portion of each second unit bar (310) is connected to the inner end of the corresponding support bar (33).

11. The combined coiled-tube heat exchanger according to claim 10, characterized in that: The outer end and the inner end of each support bar (33) are respectively connected to the corresponding first unit bar (320) and the second unit bar (310) to form an integral part.

12. The combined coiled-tube heat exchanger according to claim 9, characterized in that: A plurality of first through holes (330) extending in the up-down direction are spaced apart and distributed on the outer ring (32) and / or the support bar (33).

13. The combined coiled-tube heat exchanger according to claim 9, characterized in that: A roller (34) capable of rolling along the inner wall surface of the straight cylinder (101) is provided on the outer peripheral surface of the outer ring (32) at a position away from the gap (321).

14. The combined coiled-tube heat exchanger according to claim 9, characterized in that: The first heat exchange tubes (2) passing through each independent space (300) are divided into two groups and are respectively close to the corresponding support bars (33) and distributed on both sides of the corresponding gap (321).

15. The combined coiled-tube heat exchanger according to claim 5, characterized in that: The upper sealing head (102) and the straight cylinder (101) are detachably connected via a flange (5) and flange bolts (51).

16. The combined coil heat exchanger according to any one of claims 2 to 15, characterized in that: The first heat exchange tube (2) and the second heat exchange tube (6) which are spirally wound around the outer circumference of the central tube (3) are arranged along the length direction of the central tube (3).

17. The combined coiled-tube heat exchanger according to claim 2, characterized in that: The end of the first heat exchange tube (2) spirally wound around the outer periphery of the central tube (3) is a second straight tube section (24) extending along the first direction and arranged outside the central tube (3); The plurality of second heat exchange tubes (6) are arranged on the periphery of the second straight tube section (24).

18. The combined coiled-tube heat exchanger according to claim 17, characterized in that: It also includes a support tube (8) which is sleeved on the outer periphery of the second straight tube section (24) along the circumferential direction and fixed relative to the first tube sheet (4) used to support the end of the second straight tube section (24), and a plurality of second through holes (80) are spaced apart on the tube wall of the support tube (8); The plurality of second heat exchange tubes (6) are arranged on the periphery of the support tube (8).

19. The combined coil heat exchanger according to claim 18, characterized in that: The second heat exchange tubes (6) in the inner and outer adjacent layers and the second heat exchange tubes (6) in the innermost layer and the support tube (8) are restrained together by gaskets (9), and each gasket (9) extends along the first direction.

20. The combined coiled-tube heat exchanger according to claim 2, characterized in that: The plurality of second heat exchange tubes (6) are divided into two groups and are arranged on the outer periphery of the central tube (3) in a C-shaped manner with the C-shaped openings facing each other, thereby surrounding the central tube (3) as a whole.

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