A heat exchanger with a thermal displacement compensation support mechanism

Abstract

The present invention relates to a heat exchanger with a thermal displacement compensation support mechanism, which can also be used in a steam generator and belongs to the technical field of heat exchangers. It includes a shell, an internal heat exchange unit and a plurality of thermal displacement compensation support mechanisms, wherein the plurality of thermal displacement compensation support mechanisms are evenly distributed in the shell along the circumference, and the thermal displacement compensation support mechanism is composed of a follower support, a guide rod, a disc spring assembly, an outer cylinder, a main support seat and a spring-shaped pipe. In the present invention, an elastic disc spring support structure is adopted, which can be adjusted according to the thermal displacement caused by the temperature difference or the inconsistency of the linear expansion coefficient of the material between the two connected rigid bodies, so as to avoid the thermal stress at the connection between the rigid bodies being unable to be released due to the rigidity limitation of the support, thereby causing damage to the equipment. The thermal displacement compensation support mechanism in the present invention is arranged in a lower temperature zone, which avoids the excessive selection of high-temperature materials, increases the range of material selection, reduces the material cost, and ensures the working reliability of the thermal displacement compensation support mechanism.

Description

Technical Field

[0001] The invention relates to a heat exchanger (including a steam generator) with a thermal displacement compensation support mechanism, belonging to the technical field of heat exchangers. Background Art

[0002] It is used to support the internal structure of heat exchangers, steam generators and other equipment or similar structures, and can also be used to compensate for the axial thermal displacement of the supported internal structure.

[0003] When the internal components of high-temperature equipment such as heat exchangers and steam generators are fixed to the equipment shell but cannot fully bear the weight of the internal components, a supporting structure should be set on the internal components. Due to the large temperature difference between the equipment assembly state and the working state, when there is a temperature difference between the internal components and the shell or the linear expansion coefficient of the material is inconsistent, the equipment will produce axial thermal displacement in the working state. When the thermal displacement cannot be released, it will produce a large thermal stress, which will cause equipment damage in extreme cases.

[0004] When the temperature and pressure are not very high, the internal components of the heat exchanger can be supported by the following two methods. The first method is to connect the pipe directly to the container shell and bear the weight of the internal components of the heat exchanger, and then set a flexible structure at an appropriate position to absorb the thermal displacement of the internal components; the second method is to set a supporting structure on the internal components to bear the weight of the internal components, and then set a flexible structure at an appropriate position to absorb the thermal displacement of the internal components. Taking the supercritical and ultra-supercritical evaporators as an example, the internal working pressure of the internal heat exchange unit is above 20MPa, and the temperature of the heat exchange unit gradually rises from bottom to top, and the maximum temperature at the top can reach 700℃ or higher. The top works under harsh conditions of high temperature and high pressure. The high temperature and high pressure working conditions directly limit and affect the selection of materials and equipment costs. If method 1 is used to support the heat exchange unit, the pipe alone can no longer meet the requirements. If a supporting structure is set on the upper part according to method 2, the supporting structure should also use high-temperature materials, and the equipment cost will be very high. If the heat exchange unit is supported at the bottom of the internal component according to method 2, it is also necessary to use existing high-temperature materials on the upper part of the equipment for special flexible structure design, which increases the design difficulty and material cost. Summary of the invention

[0005] The purpose of the present invention is to provide a heat exchanger with a thermal displacement compensation support mechanism to solve the support problem of internal components of supercritical and ultra-supercritical evaporators or similar high-temperature components in the prior art, compensate for the thermal displacement of the internal components, and make the structure simple, reliable and effective.

[0006] The heat exchanger with a thermal displacement compensation support mechanism proposed in the present invention comprises a shell, an internal heat exchange unit and a plurality of thermal displacement compensation support mechanisms, wherein the plurality of thermal displacement compensation support mechanisms are evenly distributed in the shell along the circumference, the internal heat exchange unit is installed in the shell, a primary side inlet and a primary side outlet are provided at the upper part of the shell, and a secondary side outlet is provided at the upper part of the internal heat exchange unit; the thermal displacement compensation support mechanism is composed of a follower support, a guide rod, a disc spring assembly, an outer cylinder, a main support seat and a spring-shaped pipe; the spring-shaped pipe is placed at the lower part of the internal heat exchange unit, one end of the spring-shaped pipe is connected to the internal heat exchange unit, and the other end of the spring-shaped pipe extends out of the shell to become the secondary side inlet, and the spring-shaped pipe becomes a thermal displacement compensation element; the guide rod is installed under the follower support, the guide rod and the disc spring assembly are installed in the outer cylinder, the disc spring assembly is sleeved on the guide rod, the outer cylinder is fixed on the main support seat, the follower support is relatively fixed to the internal heat exchange unit, and the main support seat is relatively fixed to the shell 1.

[0007] The heat exchanger may further include a pressure ring, which is sleeved on the guide rod and is placed on the upper part of the disc spring assembly, and the top of the guide rod extends out from the top of the follower support.

[0008] The heat exchanger with a thermal displacement compensation support mechanism proposed by the present invention has the following advantages:

[0009] 1. In the heat exchanger with a thermal displacement compensation support mechanism of the present invention, an elastic disc spring support structure is adopted, which can adjust according to the thermal displacement caused by the temperature difference or the inconsistent linear expansion coefficient of the material between the two connected rigid bodies, so as to avoid the thermal stress at the connection between the rigid bodies being unable to be released due to the rigidity limitation of the support, thereby causing damage to the equipment.

[0010] 2. The thermal displacement compensation support mechanism in the heat exchanger of the present invention adopts disc springs, which have a large bearing capacity. The combined disc springs can absorb greater displacement. This support structure is particularly suitable for supporting and compensating thermal displacement of heavy internal components.

[0011] 3. The thermal displacement compensation support mechanism in the heat exchanger of the present invention is arranged in a relatively low temperature zone, thus avoiding the selection of excessive high-temperature materials, increasing the range of material selection, reducing material costs, and ensuring the working reliability of the thermal displacement compensation support mechanism.

[0012] 4. In the heat exchanger with the thermal displacement compensation support mechanism of the present invention, the entire weight load of the internal components is borne by multiple support structures evenly distributed on the inner circumference of the heat exchanger. The thermal displacement compensation mechanism at the bottom is only used to compensate for thermal displacement and bear a small amount of pipe load. The spring-shaped pipe is used as a thermal displacement compensation structure and is arranged in a low temperature zone. Therefore, the working environment is relatively good, the stress state is also better, and the design difficulty is reduced.

[0013] 5. The thermal displacement compensation support mechanism in the heat exchanger of the present invention can also use a corrugated expansion joint as a thermal displacement compensation element. As long as one end of the corrugated expansion joint is connected to the internal heat exchange unit through a pipeline, and the other end of the corrugated expansion joint extends from the shell through the pipeline to become a secondary side inlet, the corrugated expansion joint is used to compensate for thermal displacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of a heat exchanger with a thermal displacement compensation support mechanism proposed by the present invention.

[0015] Figure 2 It is a schematic structural diagram of an embodiment of a heat exchanger with a thermal displacement compensation support mechanism of the present invention.

[0016] Figure 1 and Figure 2 Among them, 1 is a shell, 2 is an internal heat exchange unit, 3 is a follower support, 4 is a guide rod, 5 is a disc spring assembly, 6 is an outer cylinder, 7 is a main support seat, 8 is a spring-shaped water pipe, and 9 is a pressure ring. DETAILED DESCRIPTION

[0017] The heat exchanger with a thermal displacement compensation support mechanism proposed by the present invention has a structure as follows: Figure 1 As shown, it includes a shell 1, an internal heat exchange unit 2 and a plurality of thermal displacement compensation support mechanisms, which are uniformly distributed in the shell 1 along the circumference, and the internal heat exchange unit 2 is installed in the shell 1. The upper part of the shell is provided with a primary side inlet and a primary side outlet, and the upper part of the internal heat exchange unit is provided with a secondary side outlet. The thermal displacement compensation support mechanism is composed of a follower support 3, a guide rod 4, a disc spring assembly 5, an outer cylinder 6, a main support seat 7 and a spring-shaped pipe 8; the spring-shaped pipe 8 is placed at the lower part of the internal heat exchange unit 2, one end of the spring-shaped pipe 8 is connected to the internal heat exchange unit 2, and the other end of the spring-shaped pipe 8 extends out of the shell 1 to become the secondary side inlet, and the spring-shaped pipe 8 becomes a thermal displacement compensation element; the guide rod 4 is installed under the follower support 3, the guide rod 4 and the disc spring assembly 5 are installed in the outer cylinder 6, the disc spring assembly 5 is sleeved on the guide rod 4, the outer cylinder 6 is fixed on the main support seat 7, the follower support 3 is relatively fixed to the internal heat exchange unit 2, and the main support seat 7 is relatively fixed to the shell 1.

[0018] The heat exchanger may further include a pressure ring 9, such as Figure 2 As shown, the pressure ring 9 is sleeved on the guide rod 4, the pressure ring 9 is placed on the upper part of the disc spring assembly 5, and the top of the guide rod 4 extends out from the top of the follower support 3.

[0019] The working principle of the thermal displacement compensation support structure in the heat exchanger of the present invention is described below in conjunction with the accompanying drawings:

[0020] The thermal displacement compensation support structure in the heat exchanger of the present invention utilizes a disc spring assembly and a main support structure to bear the gravity load and external load of the supported component. The spring-shaped pipe 8, which serves as a thermal displacement compensation element, only absorbs the displacement caused by thermal expansion and does not bear the gravity load of the supported component.

[0021] The disc spring assembly in the thermal displacement compensation support structure of the heat exchanger of the present invention can be combined with standard disc springs or standard disc springs, and can be one of a superimposed combined disc spring, a matched combined disc spring, or a composite combined disc spring. The disc spring assembly is used to bear the gravity and other external loads of the supported part. In the assembled state, the disc spring assembly will produce compression deformation because it only bears the gravity load of the supported part. When thermal displacement occurs, the supporting part needs to move axially, and at this time, the thermal displacement can be absorbed by the deformation of the disc spring assembly. The form of the disc spring assembly and the number of disc springs should be determined according to the size of the thermal displacement.

[0022] The disc spring guide structure in the thermal displacement compensation support structure is composed of a guide rod 4 and an outer cylinder 6. The structure is as follows: Figure 1 As shown, the guide rod 4 is fixed to the bottom of the follower support 3, passes through the opening at the bottom of the main support seat, and passes through the main support seat, and the outer cylinder 6 is fixed on the main support seat 7. When the equipment expands thermally, the guide rod 4 moves accordingly and plays a guiding role. The outer cylinder 6 keeps the disc spring assembly 5 intact and stable.

[0023] Another structure such as Figure 2 As shown, the guide rod 4 and the outer cylinder 6 are fixed on the main support structure 7 at the same time, and the guide rod 4 passes through the follower support. When the equipment undergoes thermal expansion, the disc spring guide rod structure does not move, and the follower support 3 moves along the guide rod 4.

[0024] The thermal displacement compensation support structure in the heat exchanger of the present invention, wherein the thermal displacement compensation is completed by a spiral coil or a corrugated expansion joint, is used to absorb the thermal displacement generated by the supported equipment and does not bear the mass load of the supported equipment.

[0025] In the use state, under cold conditions, the weight of the internal heat exchange unit 2 is transferred to the disc spring assembly 5 through the follower support 3, and the disc spring assembly 5 undergoes the first deformation. The main support seat 7 is used to finally support all structures. Under hot conditions, due to the large temperature difference between the internal heat exchange unit 2 and the shell 1, the internal heat exchange unit 2 will produce axial thermal expansion after the operation of the heat exchanger, and the follower support 3 moves downward, and the disc spring assembly 5 undergoes further compression deformation to absorb the axial thermal displacement of the internal heat exchange unit 2. The main support seat 7 bears the gravity transmitted by the internal heat exchange unit 2, the top reaction force and the reaction force after the final deformation of the disc spring assembly 5. Regardless of the working conditions, the thermal displacement compensation structure 8 does not bear the weight of the internal heat exchange unit 2, and is only used to absorb axial thermal displacement.

[0026] Figure 2Another disc spring guide structure of the present invention is shown, in which the follower support 3 is welded to the supported equipment to transfer external loads such as the weight of the supported equipment. The pressure ring 9 is an annular ring tube structure, the upper part of which is connected to the follower support 3, and the lower part is in contact with the disc spring assembly 5. When the follower support 3 generates axial displacement as required by the supporting equipment, the pressure ring 9 compresses the disc spring assembly 5 to deform the disc spring to absorb the axial displacement. The lower part of the guide rod 4 is connected to the main support seat 7, and the upper part passes through the center hole of the follower support 3, which is used to guide the disc spring assembly 5. The bottom of the outer cylinder 6 is connected to the main support structure 7, which is used to guide the pressure ring 9 and maintain the structure of the disc spring assembly 5.

[0027] The heat exchanger with a thermal displacement compensation support mechanism proposed in the present invention can be used to support internal components of high-temperature working equipment such as pressure vessels, heat exchangers, and steam generators, and is used to compensate for the displacement of internal heat exchange units caused by axial thermal expansion, effectively solving the support problem of internal components of high-temperature equipment.

[0028] The above embodiment and description are only one application of the present invention in a supercritical evaporator, and are not restrictive. Without departing from the scope of the specification, thermal compensation supports of similar structures for other containers or equipment should fall within the scope of protection of the present invention.

Claims

1. A heat exchanger with a thermal displacement compensation support mechanism, characterized in that The invention comprises a shell, an internal heat exchange unit, and a plurality of thermal displacement compensation support mechanisms, wherein the plurality of thermal displacement compensation support mechanisms are uniformly distributed in the shell along the circumference, the internal heat exchange unit being installed in the shell, the upper part of the shell being provided with a primary side inlet and a primary side outlet, and the upper part of the internal heat exchange unit being provided with a secondary side outlet; the thermal displacement compensation support mechanism is composed of a follower support, a guide rod, a disc spring assembly, an outer cylinder, a main support seat, and a spring-shaped pipe; the spring-shaped pipe is placed in the lower part of the internal heat exchange unit, one end of the spring-shaped pipe is connected to the internal heat exchange unit, and the other end of the spring-shaped pipe extends out of the shell to become the secondary side inlet, and the spring-shaped pipe becomes a thermal displacement compensation element; the guide rod is installed under the follower support, the guide rod and the disc spring assembly are installed in the outer cylinder, the disc spring assembly is sleeved on the guide rod, the outer cylinder is fixed on the main support seat, the follower support is relatively fixed to the internal heat exchange unit, and the main support seat is relatively fixed to the shell (1); the disc spring assembly is one of a superimposed combined disc spring, a matched combined disc spring, or a composite combined disc spring.

2. The heat exchanger according to claim 1, characterized in that It also includes a pressure ring, which is sleeved on the guide rod and placed on the upper part of the disc spring assembly. The top of the guide rod extends out from the top of the follower support.

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