A sealed shell-and-tube heat exchanger with load compensation

Abstract

The application discloses a tube-shell heat exchanger capable of compensating sealing load, which comprises a cylindrical shell body, the shell body has an inner cavity, the inner cavity has a heat exchange area, and a tube bundle is arranged in the heat exchange area; the tube-shell heat exchanger further comprises a cylindrical tube box which is arranged in the inner cavity and can slide along the axial direction of the shell body, one side of the tube box close to the heat exchange area is fixedly provided with a tube plate, the tube bundle is fixedly arranged on the tube plate and is in communication with the inside of the tube box, the side of the tube plate facing the heat exchange area is provided with an elastic sealing element, the elastic sealing element is abutted between the tube plate and the shell body along the axial direction of the shell body, and the tube-shell heat exchanger further comprises a supporting assembly, the supporting assembly comprises a gland and an energy accumulator, the gland is fixedly arranged on the shell body along the axial direction of the shell body, and the energy accumulator is abutted between the tube box and the gland. The tube-shell heat exchanger capable of compensating sealing load can keep sealing between the tube box and the shell body at all times under different working conditions, the tube-side medium and the shell-side medium cannot leak and pollute each other, the working performance of the heat exchanger is stable, and the safety is high.

Description

Technical Field

[0001] The present invention relates to the field of heat exchangers, and in particular to a shell and tube heat exchanger with compensable sealing load. Background Art

[0002] Shell-and-tube heat exchangers are widely used in industries such as petrochemicals and nuclear power, primarily for transferring heat between different fluids, thereby cooling and / or heating the fluids. Sealing performance has a significant impact on the performance of the heat exchanger. Currently, some high-efficiency, high-temperature, and high-pressure heat exchangers, such as double-shell heat exchangers with threaded locking rings, have different thermal expansion coefficients between the shell and its internal components, such as the tube box, tube sheet, and jack bolts. Furthermore, the seals are located relatively far from the components they compress. Furthermore, due to temperature differences between different parts of the heat exchanger during operation, when the temperature within the heat exchanger changes, the thermal deformation of each component becomes asynchronous. This causes the axial compressive load on the seal to decrease or increase accordingly with the difference in axial deformation of each component. When the axial compressive load on the seal decreases to the critical value for seal leakage, the seal will leak, leading to heat exchanger failure, contamination between the tube-side and shell-side media, and even the discharge of high-temperature media, among other production safety accidents. Summary of the Invention

[0003] The purpose of the present invention is to provide a shell and tube heat exchanger with good sealing effect and compensable sealing load to solve the sealing leakage problem caused by asynchronous thermal deformation of various components in the current shell and tube heat exchanger.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A shell-and-tube heat exchanger with compensable sealing load, comprising a cylindrical shell, the shell having an inner cavity, the inner cavity having a heat exchange area, a tube bundle being arranged in the heat exchange area, the shell-and-tube heat exchanger further comprising a cylindrical tube box that can be relatively slidably arranged in the inner cavity along the axial direction of the shell, a tube sheet being fixedly provided on a side of the tube box close to the heat exchange area, the tube bundle being fixed on the tube sheet, and the tube bundle being connected to the interior of the tube box, an elastic seal being provided on a side of the tube sheet facing the heat exchange area, the elastic seal being abutted between the tube sheet and the shell along the axial direction of the shell, the shell-and-tube heat exchanger further comprising a support assembly and an energy accumulator, the support assembly It includes a gland, which is fixed on the shell. Along the axial direction of the shell, the gland, the tube box, the tube sheet, and the heat exchange zone are arranged in sequence. The energy accumulator includes a first connecting member and a second connecting member. The axial lines of the first connecting member and the second connecting member are arranged collinearly, and the extension direction of the axial line is parallel to the axial direction of the shell. The first connecting member can be connected to the second connecting member in a relatively sliding manner along the extension direction of the axial line. The energy accumulator also includes an elastic member for providing the force required for the first connecting member to move away from the second connecting member. Along the axial direction of the shell, the energy accumulator abuts between the tube box and the gland.

[0006] Preferably, a guide member is fixed on the first connecting member, and a guide hole is provided on the second connecting member to cooperate with the guide member, the guide hole extends along the extension direction of the axial centerline, and the guide member can be inserted into the guide hole relatively slidingly along the extension direction of the guide hole. A limiting structure is also provided between the guide member and the guide hole for limiting the first connecting member from disengaging from the second connecting member in a direction away from the second connecting member.

[0007] Preferably, the first connecting member has a first pressing plate, and the second connecting member has a second pressing plate. Along the extension direction of the axial line, the first pressing plate and the second pressing plate are respectively arranged at the two ends of the energy accumulator, and the elastic member abuts between the first pressing plate and the second pressing plate.

[0008] Preferably, the first connecting member is fixedly connected to the pipe box by screw threads, and / or the second connecting member abuts against the gland.

[0009] Preferably, the energy accumulators include a plurality of groups spaced apart along the circumference of the gland.

[0010] Preferably, the tube box has a tube medium cavity, and a partition is provided in the tube medium cavity. The partition extends along the axial direction of the shell, and the partition divides the tube medium cavity into a first cavity and a second cavity that are not connected to each other. The partition also divides the tube sheet into two connected parts, namely a first part located on one side of the first cavity and a second part located on one side of the second cavity. The elastic seal is annular and abuts against the first part and the second part simultaneously along the circumference of the tube sheet. A tube-side inlet and a tube-side outlet are provided on the shell. The tube-side inlet is connected to the first cavity, and the tube-side outlet is connected to the second cavity.

[0011] Preferably, an installation step protruding radially inwardly along the shell is provided on the inner circumferential wall of the shell, and the installation step has a installation surface facing the tube sheet, and the elastic seal rests against the installation surface and the tube sheet on two different sides along its own thickness direction.

[0012] Preferably, the support assembly further comprises a load transfer plate, which is arranged between the pressure cover and the energy accumulator along the axial direction of the shell, and in a plane perpendicular to the axial direction of the shell, the projection of the energy accumulator is located inside the projection of the load transfer plate.

[0013] Further preferably, a plurality of groups of tightening bolts are provided at intervals along the circumference of the pressure cover, and the tightening bolts press the pressure cover against the load transfer plate along the axial direction of the shell. The number and position of the tightening bolts correspond one-to-one to the energy accumulator, and a corresponding group of tightening bolts extends colinearly with the axial center line of the energy accumulator.

[0014] Further preferably, the projection of the pressure cover in the plane is annular, the projection of the load transfer plate in the plane is circular, and the support assembly also includes a pressure plate, which rests between the pressure cover and the load transfer plate along the axial direction of the shell.

[0015] Due to the application of the above technical solution, the shell-and-tube heat exchanger with seal load compensation provided by the present invention compensates for the load required for axial compression of the tube sheet and the elastic seal by arranging a simple energy accumulator between the tube box and the gland. The energy accumulator has strong adaptability, and the magnitude of the compensation load can change accordingly with the axial displacement of the tube sheet and the shell. Therefore, the shell-and-tube heat exchanger can always maintain a seal between the tube box and the shell regardless of whether it is under normal temperature, heating or cooling conditions, and the tube-side medium and the shell-side medium will not leak and contaminate each other. The heat exchanger has stable operating performance and high safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Attachment Figure 1 It is a partial three-dimensional schematic diagram of a shell and tube heat exchanger with seal load compensation according to a specific embodiment of the present invention;

[0018] Attachment Figure 2 Schematic diagram of the partial structure of the shell and tube heat exchanger in this embodiment;

[0019] Attachment Figure 3 for Figure 2 The enlarged schematic diagram at point A in the middle shows the shell and tube heat exchanger at room temperature;

[0020] Attachment Figure 4 for Figure 2 The enlarged schematic diagram at point A in the middle shows the shell and tube heat exchanger in the uncompensated state of temperature reduction;

[0021] Attachment Figure 5 for Figure 2 The enlarged schematic diagram at point A in the middle shows the shell and tube heat exchanger in the temperature reduction compensation state;

[0022] Attachment Figure 6 This is a schematic structural diagram of the energy storage device in the energy release state in this embodiment;

[0023] Attachment Figure 7 This is a schematic diagram of the structure of the energy storage device in the energy storage state in this embodiment;

[0024] Wherein: 1000, shell; 1001, heat exchange area; 1100, installation step; 1100a, installation surface; 1201, shell side inlet; 1202, shell side outlet; 1301, tube side inlet; 1302, tube side outlet;

[0025] 2100, tube bundle; 2101, heat exchange tube; 2200, tube box; 2201, tube medium cavity; 2201a, first cavity; 2201b, second cavity; 2210, partition; 2220, tube box pressure plate; 2300, tube sheet; 2300a, first section; 2300b, second section;

[0026] 3000, elastic seals;

[0027] 4000, gland; 4001, thread; 4100, load transfer plate; 4200, jack bolt; 4300, ejector rod; 4400, pressure ring; 4500, pressure plate;

[0028] 5000, energy accumulator; 5100, first connecting member; 5101, first pressing plate; 5102, first column; 5110, guide member; 5110a, limiting protrusion; 5200, second connecting member; 5201, second pressing plate; 5202, second column; 5210, guide hole; 5210a, limiting boss; 5300, elastic member; 5400, fixing bolt; 5401, threaded hole;

[0029] X, axis centerline; Y, axial direction of the shell. DETAILED DESCRIPTION

[0030] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art. However, these drawings do not limit the present invention.

[0031] join Figure 1 and Figure 2 As shown, a shell and tube heat exchanger with seal load compensation includes a cylindrical shell 1000, the shell 1000 has a cylindrical inner cavity, a cylindrical pipe box 2200 is arranged in the inner cavity, and the pipe box 2200 can be relatively slidably arranged in the inner cavity along the axial direction Y of the shell.

[0032] One side of the inner cavity has a heat exchange area 1001 (the right side is used as an example from the perspective of the figure), and a tube bundle 2100 is provided in the heat exchange area 1001. A tube sheet 2300 is fixed to the side of the tube box 2200 close to the heat exchange area 1001. The tube bundle 2100 is fixed on the tube sheet 2300, and the tube bundle 2100 is connected to the interior of the tube box 2200.

[0033] In this embodiment, the tube box 2200 has a tube medium cavity 2201. A partition 2210 is provided in the tube medium cavity 2201. The partition 2210 extends along the axial direction Y of the shell. The partition 2210 divides the tube medium cavity 2201 into a first cavity 2201a and a second cavity 2201b that are not connected to each other. Correspondingly, the partition 2210 divides the tube sheet 2300 into two connected parts: a first part 2300a located on one side of the first cavity 2201a, and a second part 2300b located on one side of the second cavity 2201b.

[0034] Shell 1000 is provided with a shell-side inlet 1201, a shell-side outlet 1202, a tube-side inlet 1301, and a tube-side outlet 1302. Shell-side inlet 1201 and shell-side outlet 1202 are respectively connected to heat exchange zone 1001, tube-side inlet 1301 is connected to first chamber 2201a, and tube-side outlet 1302 is connected to second chamber 2201b. Tube bundle 2100 includes multiple parallel heat exchange tubes 2101. Each heat exchange tube 2101 is U-shaped, with its opening facing tube sheet 2300. Both ends of each heat exchange tube 2101 are welded to tube sheet 2300. One end of each heat exchange tube 2101 is connected to first chamber 2201a, and the other end is connected to second chamber 2201b.

[0035] Thus, when the shell-and-tube heat exchanger is in use, a tube-side medium is introduced into the tube-side inlet 1301. The tube-side medium enters the first chamber 2201a and then disperses into each heat exchange tube 2101. After heat exchange with the shell-side medium in the heat exchange zone 1001, it enters the second chamber 2201b and finally flows out of the tube-side outlet 1302. Simultaneously, the shell-side medium is introduced into the shell-side inlet 1201. The shell-side medium fills the heat exchange zone 1001 outside the heat exchange tubes 2101, making full contact with each heat exchange tube 2101 and indirectly contacting the tube-side medium within the heat exchange tubes 2101 to achieve heat exchange. After heat exchange, the shell-side medium flows out of the shell-side outlet 1202. The tube-side medium and the shell-side medium can be fluids such as gas and liquid, respectively.

[0036] Generally, the tube-side medium is the working medium. Depending on the usage scenario, the shell-and-tube heat exchanger can be used to cool or heat the working medium. When used for heating, the temperature of the incoming shell-side medium is higher than that of the tube-side medium. After the tube-side medium passes through the heat exchange zone 1001, the temperature increases. Conversely, when used for cooling, the temperature of the incoming shell-side medium is lower than that of the tube-side medium. After the tube-side medium passes through the heat exchange zone 1001, the temperature decreases. In this embodiment, the shell-and-tube heat exchanger is used for cooling as an example. The tube-side medium is the high-temperature oil to be cooled, and the shell-side medium is the cooling medium, typically water at room temperature.

[0037] As can be seen from the above, in this shell and tube heat exchanger, the sealing performance of the equipment is particularly important, especially the strict sealing between the tube sheet 2300 and the shell 1000 of the heat exchange area 1001. If the sealing is improper, the tube-side medium and the shell-side medium will leak and contaminate each other, seriously reducing the function of the equipment and even causing safety accidents.

[0038] In this embodiment, within the heat exchange zone 1001, the inner circumferential wall of the shell 1000 is provided with a mounting step 1100 that protrudes radially inward. The mounting step 1100 has a mounting surface 1100a facing the tube sheet 2300. An annular elastic seal 3000 is disposed between the tube sheet 2300 and the mounting surface 1100a. The elastic seal 3000, along its thickness, abuts against the mounting surface 1100a and the tube sheet 2300, respectively. The elastic seal 3000 is arranged along the circumference of the tube sheet 2300, thereby simultaneously abutting against both the first portion 2300a and the second portion 2300b of the tube sheet 2300. When the tube sheet 2300 is pressed against the elastic seal 3000, the tube sheet 2300 and the elastic seal 3000 completely seal and isolate the heat exchange zone 1001 from the tube medium cavity 2201.

[0039] See also Figure 2 and Figure 3 As shown, to provide the load required to compress the tube sheet 2300 against the elastic seal 3000, the shell-and-tube heat exchanger further includes a support assembly. The support assembly is disposed on a side of the tube box 2200 away from the heat exchange area 1001. By applying a load toward the mounting surface 1100a on the tube box 2200, the compressive load is indirectly transferred to the tube sheet 2300. The support assembly includes a gland 4000, a load transfer plate 4100, a tightening bolt 4200, a push rod 4300, a pressure ring 4400, and a pressure plate 4500.

[0040] The gland 4000 is fixedly connected to the inner wall of the housing 1000 via threads 4001. The load transfer plate 4100 abuts between the gland 4000 and the pipe box 2200 along the housing's axial direction Y. Multiple sets of jacking bolts 4200 and ejector pins 4300 are evenly spaced along the circumference of the gland 4000, with a one-to-one correspondence between their number and position. A corresponding set of jacking bolts 4200 and ejector pins 4300 extend collinearly with the axis X, with the axis X extending parallel to the housing's axial direction Y. An annular groove is defined on the side of the gland 4000 near the load transfer plate 4100, within which the compression ring 4400 is positioned. One end of each circumferential group of push rods 4300 rests against the compression ring 4400. Tightening the jacking bolts 4200 uniformly applies a compressive load to the compression ring 4400, ensuring that the compression ring 4400 rests evenly against the load transfer plate 4100. Thus, along the axial direction Y of the housing, the gland 400, load transfer plate 4100, tube box 2200, tube sheet 2300, and heat exchange zone 1001 are arranged in this order.

[0041] In addition, in the plane perpendicular to the axial direction Y of the shell, the projection of the pressure cover 4000 is annular, and the projection of the load transfer plate 4100 is circular. The pressure plate 4500 is embedded in the inside of the annular pressure cover 4000 and rests between the pressure cover 4000 and the load transfer plate 4100, so that the load applied by the pressure cover 4000 to the load transfer plate 4100 is more uniform.

[0042] In this embodiment, the shell 1000 is made of 12CrMo1 material, the internal components such as the tube box 2200 and the tube sheet 2300 are made of 304 stainless steel, and the elastic seal 3000 is made of graphite material. Thus, when the energy accumulator 5000 is not provided, the shell and tube heat exchanger has the following phenomena:

[0043] See also Figure 3 As shown, the tube box 2200, tube sheet 2300, and other components are assembled into the housing 1000 at room temperature (20°C for example). The support assembly is tightened inward, pressing the tube sheet 2300 against the elastic seal 3000. The tube sheet 2300 is subjected to an appropriate preload F0. The tube sheet 2300 and the elastic seal 3000 seal and isolate the heat exchange area 1001 from the tube medium cavity 2201. At this point, along the housing's axial direction Y, the initial distance between the elastic seal 3000 and the load transfer plate 4100 is L0 (i.e., the length of the tube medium cavity 2201). Here, L0 is 1000 mm for illustration.

[0044] When the shell-and-tube heat exchanger is in operation, high-temperature tube-side medium is introduced into the tube-side inlet 1301, causing the temperature within the tube medium cavity 2201 to gradually increase. This also gradually increases the temperature of the tube box 2200 and tube sheet 2300, which are in direct contact with the tube medium cavity 2201, as well as the portion of the shell 1000 that surrounds the tube medium cavity 2201. In this embodiment, when the shell-and-tube heat exchanger is operating stably, the average temperature within the tube medium cavity 2201 is approximately 250°C (250°C is used as an example here). Throughout the startup-operation-shutdown process, the temperature of the components surrounding the tube medium cavity 2201 changes roughly in the order of 20°C → 250°C → 20°C. Fluctuations in operating temperature may occur during this period, with the maximum temperature variation of these components reaching ΔT = 250°C - 20°C = 230°C.

[0045] During operation of this shell-and-tube heat exchanger, along the axial direction Y of the shell, on the one hand, the outer side of the load transfer plate 4100 is a non-medium cavity. Components such as the shell 1000 and the support assembly therein are not in direct contact with the tube-side or shell-side media and are less affected by temperature changes. Therefore, this non-medium cavity has a minimal impact on the sealing compression load of the elastic seal 3000. On the other hand, within the heat exchange area 1001 on the other side of the tube sheet 2300, one end of the tube bundle 2100 is free and can expand and contract relatively freely. Therefore, the heat exchange area 1001 similarly does not affect the sealing compression load of the elastic seal 3000. Therefore, the components that significantly affect the sealing compression load of the elastic seal 3000 are primarily located in the tube medium cavity 2201 section between the load transfer plate 4100 and the tube sheet 2300, primarily due to the inconsistent thermal expansion of the various components in this section along the axial direction Y of the shell when the temperature changes.

[0046] It is known that within the temperature range of 20-250°C, the linear expansion coefficient α1 of the material 12CrMo1 of the housing 1000 is smaller than the linear expansion coefficient α2 of the material 304 stainless steel of the internal components of the housing 1000 (such as the tube box 2200 and the tube sheet 2300). For example, at 250°C, α1=11.66×10 -6 / ℃,α2=17.42×10 -6 According to the formula L = ΔT × α × L0, the deformation L of the tube box 2200, tube sheet 2300, and shell 1000 located in the tube medium cavity 2201 along the shell axial direction Y can be calculated separately when the temperature changes. Since the tube box 2200 and tube sheet 2300 are fixedly connected and made of the same material, they can be considered as a whole for calculation of their deformation L.

[0047] Specifically, calculations show that when ΔT = 230°C, the combined deformation L2 of the tube box 2200 and tube sheet 2300 exceeds the deformation L1 of the shell 1000 located in the tube medium cavity 2201, and the difference in deformation ΔL = L2 - L1 ≈ 1.3 mm. Because one end of the tube box 2200 is relatively fixed by a support assembly, the tube box 2200 and tube sheet 2300 expand primarily toward the heat exchange zone 1001, and their expansion is greater than the expansion of the shell 1000 located in the tube medium cavity 2201. Therefore, under elevated temperatures, the tube sheet 2300 can further press the elastic seal 3000 against the mounting surface 1100a. At this point, the compression load F1 of the tube sheet 2300 exceeds the preload F0, preventing leakage.

[0048] However, see Figure 4As shown, when the operating temperature of the shell and tube heat exchanger fluctuates (from high temperature to low temperature) or is in the process of shutdown and cooling, the temperature in the tube medium cavity 2201 and the heat exchange area 1001 gradually decreases. At this time, the tube box 2200, the tube sheet 2300 and the shell 1000 all cool down and shrink. Since α1<α2, the tube box 2200 and the tube sheet 2300 shrink faster along the axial direction Y of the shell, so that the tube sheet 2300 and the mounting surface 1100a tend to move away from each other, and a displacement difference gradually appears between the tube sheet 2300 and the elastic seal 3000. When the displacement difference is small, the compression amount and the clamping load of the elastic seal 3000 decrease synchronously. When the clamping load F2 decreases to the critical value of the sealing leakage of the shell-side medium and / or the tube-side medium, the elastic seal 3000 will fail and leak. When the displacement difference increases further, the tube sheet 2300 will separate from the elastic seal 3000, and a maximum gap of ΔL may be generated. At this time, more serious leakage will occur, resulting in mutual contamination between the tube-side medium and the shell-side medium, heat exchange failure, and even safety accidents.

[0049] When the temperature in the tube medium cavity 2201 and the heat exchange area 1001 is completely restored to room temperature, all components are restored to their initial length L0, and the tube sheet 2300 can be in sealing contact with the elastic seal 3000 again.

[0050] It should be noted that during actual operation, on the one hand, there are temperature differences between the first chamber 2201a, the second chamber 2201b, and different parts of the heat exchange zone 1001, resulting in uneven heating of the first portion 2300a and the second portion 2300b of the tube sheet 2300. On the other hand, there are also differences in the temperature changes of the shell 1000, the tube box 2200, and the tube sheet 2300. Because the tube box 2200 and the tube sheet 2300 are directly exposed to the high-temperature tube-side medium, while the shell 1000 is relatively located on the outside, at the same time, the temperature of the tube box 2200 and the tube sheet 2300 is higher, while the temperature of the shell 1000 is lower. The temperature change ΔT of the shell 1000 during the entire heating process is also smaller, further reducing the deformation L1 of the shell 1000 and increasing the deformation difference ΔL. These factors make the sealing leakage problem caused by the asynchronous thermal deformation of the components in this shell and tube heat exchanger more complex and serious.

[0051] In order to solve the above problems, the shell and tube heat exchanger with sealing load compensation in this embodiment is equipped with multiple groups of energy storage devices 5000 between the load transfer plate 4100 and the tube box 2200 to compensate for the reduced compression and clamping load of the elastic seal 3000 during the cooling process, so that the tube plate 2300 and the mounting surface 1100a can maintain a seal.

[0052] Specifically, see Figure 1 and Figure 2As shown, a pipe box pressure plate 2220 is fixed to one side of the pipe box 2200 facing the load transfer plate 4100. The pipe box pressure plate 2220 has multiple mounting holes evenly spaced along its circumference. Each energy accumulator 5000 is inserted into these mounting holes in a one-to-one correspondence. The positions of the energy accumulators 5000 also correspond one-to-one with the aforementioned jacking bolts 4200 and push rods 4300. Each group of energy accumulators 5000 is centered around the axis X and can be extended and retracted along the axis X. In a plane perpendicular to the axial direction Y of the housing, the projections of all energy accumulators 5000 are located within the projection of the load transfer plate 4100. This allows the support assembly to first transfer the compressive load to the energy accumulators 5000, which is then further transferred from the energy accumulators 5000 to the pipe box 2200 and tube plate 2300.

[0053] See also Figure 6 and Figure 7 As shown, each energy accumulator 5000 is cylindrical in shape, and its components are arranged collinearly with the axis X. The energy accumulator 5000 specifically includes a first connecting member 5100 and a second connecting member 5200 that are relatively slidably connected along the extension direction of the axis X, and an elastic member 5300 for providing the force required for the first connecting member 5100 and the second connecting member 5200 to move away from each other.

[0054] The first connecting member 5100 includes a first pressing plate 5101 and a first post 5102 fixed to the first pressing plate 5101. The outer diameter of the first pressing plate 5101 is larger than that of the first post 5102. The second connecting member 5200 includes a second pressing plate 5201 and a second post 5202 fixed to the second pressing plate 5201. The outer diameter of the second pressing plate 5201 is larger than that of the second post 5202. Along the extension direction of the axis X, the first pressing plate 5101 and the second pressing plate 5201 are respectively arranged at the two ends of the energy accumulator 5000. The elastic member 5300 is simultaneously sleeved on the first post 5102 and the second post 5202, and the two axial ends of the elastic member 5300 respectively abut against the first pressing plate 5101 and the second pressing plate 5201. In this embodiment, the outer diameters of the first pressing plate 5101 and the second pressing plate 5201 are equal, and the outer diameter of the elastic member 5300 is not larger than the outer diameter of the first pressing plate 5101 , so that the energy accumulator 5000 can be stably inserted into the mounting hole without shaking.

[0055] Furthermore, a sliding guide structure is provided between the first column 5102 and the second column 5202. The structure includes a guide member 5110 fixed to the first column 5102 and a guide hole 5210 defined in the second column 5202. The guide member 5110 is inserted into the guide hole 5210 so as to slide relative to the guide hole 5210 along the extension direction of the guide hole 5210 (i.e., the extension direction of the axis X). To prevent the first connecting member 5100 and the second connecting member 5200 from sliding out of each other, the guide member 5110 further includes a limiting protrusion 5110a on one end away from the first column 5102. A limiting boss 5210a is provided on one side of the guide hole 5210 near the limiting boss 5110a. The inner diameter of the limiting boss 5210a is smaller than the outer diameter of the limiting boss 5110a, thereby preventing the limiting boss 5110a from sliding out of the guide hole 5210.

[0056] As described above, the arrangement of the energy storage device 5000 enables the first connecting member 5100, the second connecting member 5200 and the elastic member 5300 to interact with each other along the extension direction of the axis X. Figure 6 As shown, when no external load is applied, the energy accumulator 5000 is in an energy release state, the elastic member 5300 pushes the first connecting member 5100 and the second connecting member 5200 away from each other, and the energy accumulator 5000 extends. Figure 7 As shown, when the external load increases, the energy accumulator 5000 enters an energy storage state, and the first connecting member 5100 and / or the second connecting member 5200 are squeezed toward each other, thereby compressing the elastic member 5300 and shortening the energy accumulator 5000. The load applied by the energy accumulator 5000 to the outside world is negatively correlated with its length: the shorter the energy accumulator 5000, the greater the applied load. When the elastic member 5300 is fully released and the energy accumulator 5000 is at its longest length, the applied load is zero.

[0057] It should be noted that the sum of the lengths of the first column 5102 and the second column 5202 should be equal to the length of the elastic member 5300 when it is at the maximum allowable compression. Therefore, when the energy accumulator 5000 is subjected to a large compression load and the first column 5102 and the second column 5202 are completely in contact with each other, the elastic member 5300 will not be crushed and lose its elasticity, thereby protecting the working performance of the energy accumulator 5000.

[0058] In this embodiment, a threaded hole 5401 is provided on the first connecting member 5100, so that the energy accumulator 5000 can be fixedly connected to the tube box pressure plate 2220 via the fixing bolt 5400. The outer end of the second connecting member 5200 is flush with the opening of the mounting hole or partially extends outside the mounting hole, so that the second connecting member 5200 can abut against the load transfer plate 4100. In this way, the energy accumulator 5000 is equivalent to abutting between the tube box 2200 and the pressure cover 4000 along the axial direction Y of the inner cavity, so that the tube box 2200 and the tube sheet 2300 are arranged on an elastic support. Multiple groups of energy accumulators 5000 can simultaneously apply a load toward the mounting surface 1100a to the tube sheet 2300, providing sealing and compression load compensation for the tube sheet 2300.

[0059] In this embodiment, the working principle of the shell and tube heat exchanger with seal load compensation is described in detail as follows:

[0060] See also Figure 3 As shown, at room temperature, the accumulator 5000 is appropriately compressed, providing a certain preload F0 to the tube sheet 2300 , and the tube sheet 2300 and the elastic seal 3000 seal the heat exchange area 1001 and the tube medium cavity 2201 .

[0061] Under the conditions of temperature rise and high-temperature operation, the tube box 2200 and the tube sheet 2300 expand due to heat, the elastic seal 3000 is further tightened, and the energy accumulator 5000 is further compressed. However, due to the limiting effect of the first column 5102 and the second column 5202, the elastic component 5300 can be protected from being crushed.

[0062] During cooling, the tube sheet 2300 and the elastic seal 3000 tend to move away from each other. At this point, the accumulator 5000 provides load compensation to the tube sheet 2300, enabling them to maintain sealed contact. Under the force of the elastic member 5300, the first connector 5100 and the second connector 5200 move away from each other, with the second connector 5200 resting against the load transfer plate 4100. The first connector 5100 applies a load toward the elastic seal 3000 to the tube box 2200, pushing it toward the mounting surface 1100a. This allows the tube sheet 2300 to maintain contact with the elastic seal 3000, with the compressive load between them sufficient to achieve a seal and prevent leakage. Consequently, under the force of the first connector 5100, a gap of ΔL appears between the tube box 2200 and the load transfer plate 4100.

[0063] In other embodiments, the shell-and-tube heat exchanger can also be used to heat the tube-side medium. For example, the tube-side medium can be high-pressure gas at approximately 150°C. After heating, the tube-side medium flowing out of the tube-side outlet 1302 is approximately 250°C. In this case, during the startup, operation, and shutdown process of the shell-and-tube heat exchanger, the tube box 2200, tube sheet 2300, and shell 1000 in the tube medium cavity 2201 will also experience a temperature change trend of first increasing and then decreasing. The energy accumulator 5000 can also compensate for the compression load of the elastic seal 3000 during this temperature change, ensuring a good sealing effect. The operating principle is essentially the same as in this embodiment and will not be further described here.

[0064] In summary, the shell-and-tube heat exchanger with seal load compensation in this embodiment, by providing multiple sets of energy accumulators 5000, can provide a compensating load to the tube sheet 2300 according to the actual displacement difference, thereby overcoming the seal leakage problem caused by the asynchronous thermal deformation of the internal components and the shell 1000 of the shell-and-tube heat exchanger, greatly improving the sealing performance of the shell-and-tube heat exchanger, and ensuring stable and reliable operation of the equipment.

[0065] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A shell-and-tube heat exchanger with seal load compensation, comprising a cylindrical shell having an inner cavity, a heat exchange area having a tube bundle disposed therein, characterized in that: The shell and tube heat exchanger further includes a cylindrical tube box that is relatively slidably disposed in the inner cavity along the axial direction of the shell. A tube sheet is fixedly disposed on a side of the tube box close to the heat exchange zone. The tube bundle is fixedly disposed on the tube sheet and communicates with the interior of the tube box. An elastic seal is disposed on a side of the tube sheet facing the heat exchange zone. The elastic seal abuts between the tube sheet and the shell along the axial direction of the shell. The shell and tube heat exchanger further includes a support assembly and an energy accumulator, the support assembly includes a gland, the gland is fixedly mounted on the shell, and along the axial direction of the shell, the gland, the tube box, the tube sheet, and the heat exchange zone are sequentially arranged, the energy accumulator includes a first connecting member and a second connecting member, the axis of the first connecting member and the second connecting member are collinearly arranged, and the extension direction of the axis is parallel to the axial direction of the shell, the first connecting member can be connected to the second connecting member in a relatively slidable manner along the extension direction of the axis, the energy accumulator further includes an elastic member for providing the force required for the first connecting member to move away from the second connecting member, and along the axial direction of the shell, the energy accumulator abuts between the tube box and the gland; A guide member is fixedly provided on the first connecting member, and a guide hole is provided on the second connecting member to cooperate with the guide member. The guide hole extends along the extension direction of the axial centerline, and the guide member can be inserted into the guide hole relatively slidingly along the extension direction of the guide hole. A limiting structure is also provided between the guide member and the guide hole for limiting the first connecting member from disengaging from the second connecting member in a direction away from the second connecting member.

2. The shell and tube heat exchanger with seal load compensation according to claim 1, characterized in that: The first connecting member has a first pressing plate, and the second connecting member has a second pressing plate. Along the extension direction of the axial line, the first pressing plate and the second pressing plate are respectively arranged at the two ends of the energy accumulator, and the elastic member abuts between the first pressing plate and the second pressing plate.

3. The shell and tube heat exchanger with seal load compensation according to claim 1, characterized in that: The first connecting member is fixedly connected to the pipe box by screw threads, and / or the second connecting member abuts against the gland.

4. The shell and tube heat exchanger with seal load compensation according to any one of claims 1 to 3, characterized in that: The energy accumulators include a plurality of groups arranged at intervals along the circumference of the gland.

5. The shell and tube heat exchanger with seal load compensation according to claim 1, characterized in that: The tube box has a tube medium cavity, and a partition is provided in the tube medium cavity. The partition extends along the axial direction of the shell, and the partition divides the tube medium cavity into a first cavity and a second cavity that are not connected to each other. The partition also divides the tube sheet into two connected parts, namely a first part located on one side of the first cavity and a second part located on one side of the second cavity. The elastic seal is annular and abuts against the first part and the second part simultaneously along the circumference of the tube sheet. The shell is provided with a tube side inlet and a tube side outlet. The tube side inlet is connected to the first cavity, and the tube side outlet is connected to the second cavity.

6. The shell and tube heat exchanger with seal load compensation according to claim 1, characterized in that: An installation step protruding radially inwardly along the shell is provided on the inner circumferential wall of the shell, and the installation step has a installation surface facing the tube sheet. The elastic seal rests against the installation surface and the tube sheet on two different sides along its own thickness direction.

7. The shell and tube heat exchanger with seal load compensation according to claim 1, characterized in that: The support assembly also includes a load transfer plate, which is arranged between the pressure cover and the energy accumulator along the axial direction of the shell. In a plane perpendicular to the axial direction of the shell, the projection of the energy accumulator is located inside the projection of the load transfer plate.

8. The shell and tube heat exchanger with seal load compensation according to claim 7, characterized in that: A plurality of sets of tightening bolts are provided at intervals along the circumference of the gland, and the tightening bolts press the gland against the load transfer plate along the axial direction of the shell. The number and position of the tightening bolts correspond one-to-one to the energy accumulator, and a corresponding set of tightening bolts extends colinearly with the axial center line of the energy accumulator.

9. The shell and tube heat exchanger with seal load compensation according to claim 7, characterized in that: The projection of the pressure cover in the plane is annular, the projection of the load transfer plate in the plane is circular, and the support assembly further includes a pressure plate, which abuts between the pressure cover and the load transfer plate along the axial direction of the shell.

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