A sealing and fastening device for a detachable spiral plate heat exchanger core structure

Abstract

This invention discloses a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger, relating to the field of heat exchange equipment technology. This device addresses the sealing challenge at the core end of a detachable spiral plate heat exchanger, which serves as the medium introduction channel, aiming to solve the problem of easy failure and leakage of existing sealing structures under high temperature and high pressure conditions. The device is located at the lower end of the heat exchanger core and employs a three-stage sealing structure: the first stage seal consists of the equipment's large flange, a large toothed gasket, and a large flat cover; the second stage seal consists of a circular end plate connecting the core, a small toothed gasket, and an inner lining plate of the large flat cover; the third stage seal consists of a clamping ring, a preload distribution bolt group, and a circular sealing ring that fits between the clamping ring and the large flat cover. Through the synergistic effect of the three-stage seal, this invention achieves dynamic pressure compensation, significantly improving the sealing reliability and pressure adaptability of the core end, and effectively meeting the requirements for long-term stable operation under high-parameter conditions.

Description

Technical Field

[0001] This invention relates to the field of heat exchange equipment technology, specifically to a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger. This device is particularly suitable for heat exchange scenarios involving high-pressure (up to 5.0 MPa) and high-temperature (up to 500°C) media in industries such as chemical, pharmaceutical, and petroleum refining. Background Technology

[0002] Spiral plate heat exchangers are widely used in various industrial fields due to their compact structure and high heat exchange efficiency. However, existing spiral plate heat exchangers generally suffer from the following drawbacks: 1. In traditional designs, end sealing of the intermediate core structure is difficult. Especially for through-type spiral plate heat exchangers, where the intermediate core serves as the medium introduction channel on one side, and the end plates need to be perforated and directly welded to the connecting pipes, thermal stress can cause seal failure under medium to high pressure and high temperature, easily leading to medium leakage.

[0003] 2. Traditional spiral plate heat exchangers use rubber gaskets and flat caps for sealing and fastening the end plates. Under high temperature and high pressure conditions, these gaskets are prone to aging and causing media leakage. They cannot meet the long-term reliable operation requirements under high parameter conditions such as 5.0MPa and 500℃, and pose significant safety hazards and maintenance costs. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger, so as to solve the technical problems of poor end sealing performance and difficulty in adapting to high temperature and high pressure conditions in the prior art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger, the detachable spiral plate heat exchanger comprising an outer cylinder, large equipment flanges at both ends of the outer cylinder, a large equipment flat cover detachably connected to the large equipment flanges, a spiral body disposed within the outer cylinder, and a core body in the middle of the spiral body, the core body being cylindrical, characterized in that: the upper end of the core body is sealed with a spherical end plate, and the lower end of the core body is a detachable sealing and fastening device with a three-stage sealing structure.

[0006] Furthermore, the sealing and fastening device includes: The large toothed gasket is installed between the large flange and the large flat cover of the equipment. The large flange, the large toothed gasket, and the large flat cover of the equipment form a primary sealing structure. A circular end plate is sealed to the lower end of the core. A hole is opened in the center of the circular end plate to fix the connecting pipe. An annular groove is formed on the lower surface of the circular end plate, and a small toothed gasket is embedded in the annular groove. A liner is installed inside the large flat cover of the equipment. The circular end plate, the small toothed gasket, and... LinerForming a two-stage sealing structure; A clamping ring is located below the large flat cover of the equipment. The large flat cover has a central through hole in the middle. The outer diameter of the clamping ring is larger than the diameter of the central through hole. The clamping ring is connected to the lower end face of the circular end plate by several evenly distributed bolt groups. The middle part of the bolt group passes through the central through hole. The upper end face of the clamping ring has a first annular semicircular groove with residual grooves at both ends. The lower end face of the large flat cover has a second annular semicircular groove with residual grooves at both ends, corresponding to the first annular semicircular groove. A circular sealing ring is embedded in the first annular semicircular groove and the second annular semicircular groove. The circular end plate, bolt groups, large flat cover, circular sealing ring, and clamping ring form a three-level sealing structure.

[0007] Furthermore, the bolt group is a preload distribution bolt group.

[0008] Furthermore, the lower end face of the circular end plate is flush with the lower end face of the spiral body, and a gap is left between the upper end face of the spherical end plate and the upper end face of the spiral body.

[0009] Furthermore, the large toothed gasket and the small toothed gasket of the device are metal toothed gaskets, and the circular sealing ring is a non-metallic gasket that is resistant to high temperature and high pressure and corrosion.

[0010] Furthermore, the lower end of the connecting pipe passes through the large flat cover of the equipment and the clamping ring in sequence, and then connects to the cold side inlet flange.

[0011] Furthermore, the end face of the spiral body is 2.5mm higher than the sealing surface of the large flange of the equipment, and the sealing surface of the large flange of the equipment is tightly fitted with the large toothed gasket of the equipment.

[0012] Furthermore, the spiral is formed by welding two parallel metal plates onto a core and rolling them together. A spacer is provided between the metal plates. One of the metal plates has its edges turned up and down to form a through channel and a closed channel. The two ends of the closed channel are sealed by welding the edges together. The end face of the closed channel near the core is sealed by welding flat steel. Several cold medium flow holes are evenly opened on the side wall of the core near the closed channel.

[0013] Furthermore, a pipe box is provided on one side of the outer cylinder, with a cold-side outlet at the top and a hot-side inlet at the bottom. A blocking plate is provided inside the pipe box, dividing the inner cavity of the pipe box into an upper cavity and a lower cavity. The upper cavity is connected to the closed channel and the cold-side outlet, respectively, and the lower cavity is connected to the through channel and the hot-side inlet, respectively. A hot-side outlet is provided in the middle of the large flat cover of the equipment located on one side of the upper end of the outer cylinder, and the hot-side outlet is connected to the through channel.

[0014] Furthermore, a hot-side drain port is provided on the large flat cover of the equipment located on one side of the upper end of the outer cylinder, and a hot-side discharge port is provided on the large flat cover of the equipment located on one side of the upper end of the outer cylinder. A cold-side drain port and a cold-side discharge port are also provided on the side wall of the outer cylinder. The cold-side drain port is located above the cold-side outlet, and the cold-side discharge port is located below the hot-side inlet. Both the hot-side drain port and the hot-side discharge port are connected to the through channel, and both the cold-side drain port and the cold-side discharge port are connected to the closed channel.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are as follows: (1) The present invention adopts a three-stage reinforced sealing structure, which enables the device to be reliably applied to extreme working conditions with working pressure up to 5.0 MPa and working temperature up to 500℃, greatly expanding the application range of detachable spiral plate heat exchangers and meeting the needs of high-parameter heat exchange equipment in the fields of chemical industry and petroleum refining.

[0016] (2) The three-stage sealing structure of the present invention works synergistically to achieve dynamic pressure compensation and extremely low leakage rate; the first stage seal achieves a large-area preliminary seal, the second stage seal strengthens the medium inlet point, and the third stage seal, through an independent pre-tightening force distribution bolt group, can still apply a stable and controllable clamping force to the second stage seal when the large flat cover of the equipment may deform, thus achieving dynamic pressure compensation. This effectively solves the problem that traditional single-stage seals are prone to failure under pressure and temperature fluctuations, and can reduce the leakage rate of the core structure by more than 50% compared with the traditional structure, ensuring the long-term stable operation and safety of the system.

[0017] (3) The clamping ring and the preload distribution bolt group used in this invention work together so that the pressure acting on the small toothed gasket at the core sealing point no longer depends entirely on the bolt preload of the large flange of the equipment, thereby isolating external factors from interference with the core seal. Combined with the uniform force characteristics of the circular sealing ring, the pressure fluctuation range of the sealing surface can be controlled within ±5%, providing a sealing stability far higher than that of conventional designs, and minimizing sealing pressure fluctuation.

[0018] (4) The three-stage sealing and fastening device of the present invention integrates the complex sealing function between the lower end of the core and the large flat cover of the equipment. The structure is compact and does not occupy too much extra space. At the same time, due to the use of a detachable structure (bolted connection), the installation, maintenance and internal cleaning of the equipment are very convenient. Only the bolts and pre-tightening force distribution bolt group on the large flange of the equipment need to be removed and installed to maintain or replace the core and sealing elements, which reduces the operation and maintenance cost of the whole life cycle.

[0019] (5) This invention solves the sealing problem under high temperature and high pressure, effectively prevents safety and environmental accidents and equipment corrosion caused by leakage of dangerous media, and significantly improves the overall operational reliability and service life of the spiral plate heat exchanger. Attached Figure Description

[0020] Figure 1 This is a front view of a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to the present invention. Figure 2 This is a main sectional view of a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to the present invention. Figure 3 yes Figure 1 A magnified view of a section at point A in the middle; Figure 4 yes Figure 2 A magnified view of a section at point B in the middle; Reference numerals: 1-Outer cylinder, 2-Equipment large flange, 201-Equipment large flange sealing surface, 3-Equipment large flat cover, 301-Central through hole, 4-Spiral body, 401-Spiral body upper end face, 402-Spiral body lower end face, 403-Through channel, 404-Closed channel, 5-Core body, 501-Cold medium flow hole, 6-Equipment large toothed gasket, 7-Circular end plate, 8-Connecting pipe, 9-Small toothed gasket, 10-Pressure ring, 11-Bolt assembly, 12-Liner, 13-Circular sealing ring, 14-Cold side inlet flange, 15-Flat steel, 16-Pipe box, 17-Blocking plate, 18-Cold side outlet, 19-Hot side inlet, 20-Hot side outlet, 21-Hot side drain port, 22-Hot side discharge port, 23-Cold side drain port, 24-Cold side discharge port. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0022] In the description of this invention, it should be understood that the terms "upper", "lower", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0023] Example Please see Figures 1 to 4 The present invention provides a sealing and fastening device for the core structure of a detachable spiral plate heat exchanger, which is suitable for a detachable through-type spiral plate heat exchanger.

[0024] like Figure 1 and Figure 2As shown, the detachable spiral plate heat exchanger mainly includes an outer cylinder 1, equipment flanges 2 welded to both ends of the outer cylinder 1, equipment flat cover 3 detachably connected to the equipment flanges 2 by bolts, a spiral 4 disposed inside the outer cylinder 1, and a core 5 located at the center of the spiral 4. The core 5 adopts a cylindrical structure and serves as the introduction channel for the cold medium.

[0025] Specifically, the spiral 4 is formed by welding two parallel metal plates onto the core 5 and then rolling them together. The metal plates are supported by spacer posts (not shown in the figure) to ensure the spacing between the flow channels. After rolling, the metal plates are flanged to form two independent spiral channels: a through channel 403 and a closed channel 404. The two ends of the closed channel 404 are flanged and sealed by welding to allow the flow of the cooling medium. The end face of the closed channel 404 near the core 5 is sealed by welding with flat steel 15 to prevent short circuits of the medium. To introduce the cooling medium, several cooling medium flow holes 501 are evenly formed on the side wall of the core 5 near the closed channel 404.

[0026] A pipe box 16 is provided on one side of the outer cylinder 1. The upper part of the pipe box 16 is a cold-side outlet 18, and the lower part is a hot-side inlet 19. A blocking plate 17 is provided inside the pipe box 16, which divides it into independent upper and lower cavities. The upper cavity is connected to the closed channel 404 of the spiral 4 and the cold-side outlet 18; the lower cavity is connected to the through channel 403 of the spiral 4 and the hot-side inlet 19. A hot-side outlet 20 is provided at the center of the large flat cover 3 at the upper end, which is connected to the through channel 403. In addition, the equipment is also provided with pipe ports for venting and maintenance: a hot-side drain port 21 and a hot-side discharge port 22 on the large flat cover 3 at the upper end, and a cold-side drain port 23 and a cold-side discharge port 24 on the side wall of the outer cylinder 1. The hot-side drain port 21 and the hot-side discharge port 22 are both connected to the through channel 403, and the cold-side drain port 23 and the cold-side discharge port 24 are both connected to the closed channel 404.

[0027] like Figure 2 , Figure 3 and Figure 4 As shown, the upper end of the core 5 is sealed by welding with a spherical end plate, while the lower end of the core 5 uses the three-stage reinforced sealing and fastening device of this invention. The specific structure is as follows: The first-stage seal is formed by the large toothed gasket 6, the large flange 2, and the large flat cover 3. The large toothed gasket 6 is located between the large flange 2 and the large flat cover 3, and the sealing surface 201 of the large flange is tightly fitted with the large toothed gasket 6. The lower end face 402 of the spiro body is 2.5mm higher than the sealing surface 201 of the large flange. The large toothed gasket 6 is placed on the sealing surface 201 of the large flange. When the large flat cover 3 is tightened to the large flange 2 with bolts, the first-stage seal is formed, achieving a preliminary seal on the entire lower end face of the spiro body 4.

[0028] Second-stage seal: consisting of circular end plate 7, small toothed gasket 9, and large flat cover of equipment 3. Upper lining plate 12 The core 5 is formed by sealing and welding a circular end plate 7 to its lower end, with its lower end face flush with the lower end face 402 of the spiral. A central opening is formed in the circular end plate 7, and a connecting pipe 8 is welded thereon for introducing the cold medium. An annular groove is formed on the lower end face of the circular end plate 7, and a small toothed gasket 9 is embedded and fixed within this groove. After the large flat cover 3 is installed, its inner surface liner 12 fits tightly against the small toothed gasket 9, thus forming a second-level seal in a localized area of ​​the core 5, providing enhanced sealing at the medium inlet.

[0029] The third-level seal consists of a circular end plate 7, bolt sets 11, a large flat cover 3, a circular sealing ring 13, and a clamping ring 10. It is positioned below the large flat cover 3 and works in conjunction with the second-level seal. The large flat cover 3 has a central through-hole 301 for the pipe 8 to pass through. The clamping ring 10 is fitted onto the pipe 8 and positioned below the large flat cover 3. The outer diameter of the clamping ring 10 is larger than the diameter of the central through-hole 301. Multiple preload-distributing bolt sets 11 are evenly distributed circumferentially. The bolt sets 11 pass through the clamping ring 10 and the central through-hole 301, and are welded upwards to the lower end face of the circular end plate 7, thereby securing the clamping ring 10, the large flat cover 3, and the circular end plate 7. The upper end face of the clamping ring 10 has a first annular semicircular groove with residual grooves at both ends. On the lower end face of the large flat cover 3, opposite to the first annular semicircular groove, a second annular semicircular groove with residual grooves at both ends is formed. A circular sealing ring 13 is embedded in the first and second annular semicircular grooves. When the preload distribution bolt group 11 is tightened, the clamping ring 10 presses against the large flat cover 3, causing the circular sealing ring 13 to form a tight fit and mutual compression seal within the groove. The residual grooves increase the clamping elasticity when the gasket is tightened, improving the sealing effect. This sealing structure not only establishes an effective seal between the clamping ring 10 and the large flat cover 3, but more importantly, it applies a controllable and independent clamping force to the circular end plate 7 through the tension of the bolt group 11, ensuring the sealing specific pressure of the small toothed gasket 9 in the second-stage seal. Simultaneously, this structure also provides auxiliary support and secondary sealing for the large flat cover 3.

[0030] In this invention, the large toothed gasket 6 and the small toothed gasket 9 of the device are both made of high temperature and high pressure resistant and corrosion resistant metal toothed gasket material, and the circular sealing ring 13 is made of high temperature and high pressure resistant and corrosion resistant non-metallic gasket material.

[0031] In this invention, the pressure fluctuation range of the sealing surface is controlled within ±5% by means of the clamping ring 10 and the preload distribution bolt group 11.

[0032] The synergistic working principle of the three-stage seal: Under normal operation, the first-stage seal bears the main pressure from the medium inside the spiral body 4. When operating conditions fluctuate, such as pressure or temperature increases causing slight deformation of the large flat cover 3, the sealing pressure of the first-stage seal may decrease. At this time, the clamping force, pre-set by the pre-tightening bolt group 11 and acting on the circular end plate 7 and the clamping ring 10, remains constant, allowing the second and third-stage seals to function independently and stably, effectively preventing medium leakage from the root of the core body 5. This structure achieves dynamic pressure compensation, meaning that when the external sealing environment changes, the internal core sealing point can still maintain a reliable sealing state.

[0033] During operation, the cold medium enters through the cold-side inlet flange 14 at the lower end of the connecting pipe 8, passes through the circular end plate 7 and the core 5 in sequence, and then enters the closed channel 404 of the spiral body 4 through the cold medium flow hole 501 on the side wall of the core body 5. After flowing inside the spiral body, it flows out from the cold-side outlet 18. The hot medium enters through the hot-side inlet 19, passes through the lower cavity of the pipe box 16 and enters the through channel 403 of the spiral body 4. After counter-current or cross-current heat exchange with the cold medium inside the spiral body, it flows out from the hot-side outlet 20.

[0034] Testing has shown that the sealing and fastening device for the core structure of a detachable spiral plate heat exchanger of the present invention can adapt to high temperature and high pressure conditions, with a pressure resistance of up to 5.0 MPa and a temperature resistance of up to 500 degrees Celsius.

[0035] The above description represents preferred embodiments of the present invention, used to explain the technical solutions of the present invention. Those skilled in the art can make conventional modifications, equivalent substitutions, and improvements within the spirit and principles of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art and can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein.

Claims

1. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger, the detachable spiral plate heat exchanger comprising an outer cylinder, large equipment flanges at both ends of the outer cylinder, a large equipment flat cover detachably connected to the large equipment flanges, a spiral body disposed within the outer cylinder, and a core body in the middle of the spiral body, the core body being cylindrical, characterized in that: The upper end of the core is sealed with a spherical end plate, and the lower end of the core is sealed with a detachable sealing and fastening device with a three-stage sealing structure; the sealing and fastening device includes: The large toothed gasket is installed between the large flange and the large flat cover of the equipment. The large flange, the large toothed gasket, and the large flat cover of the equipment form a primary sealing structure. A circular end plate is sealed to the lower end of the core. A hole is opened in the middle of the circular end plate to fix the connecting pipe. An annular groove is opened on the lower end face of the circular end plate. A small toothed gasket is embedded in the annular groove. A liner is set on the inner side of the large flat cover of the equipment. The circular end plate, the small toothed gasket and the liner form a two-stage sealing structure. A clamping ring is located below the large flat cover of the equipment. The large flat cover has a central through hole in the middle. The outer diameter of the clamping ring is larger than the diameter of the central through hole. The clamping ring is connected to the lower end face of the circular end plate by several evenly distributed bolt groups. The middle part of the bolt group passes through the central through hole. The upper end face of the clamping ring has a first annular semicircular groove with residual grooves at both ends. The lower end face of the large flat cover has a second annular semicircular groove with residual grooves at both ends, corresponding to the first annular semicircular groove. A circular sealing ring is embedded in the first annular semicircular groove and the second annular semicircular groove. The circular end plate, bolt groups, large flat cover, circular sealing ring, and clamping ring form a three-level sealing structure.

2. The sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The bolt group is a preload distribution bolt group.

3. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The lower end face of the circular end plate is flush with the lower end face of the spiral body, and a gap is left between the upper end face of the spherical end plate and the upper end face of the spiral body.

4. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The large toothed gasket and small toothed gasket of the device are both metal toothed gaskets, and the circular sealing ring is a non-metallic gasket that is resistant to high temperature and high pressure and corrosion.

5. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The lower end of the pipe passes through the large flat cover of the equipment and the clamping ring in sequence, and then connects to the cold side inlet flange.

6. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The end face of the spiral body is 2.5mm higher than the sealing surface of the large flange of the equipment, and the sealing surface of the large flange of the equipment is tightly fitted with the large toothed gasket of the equipment.

7. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: The spiral is formed by welding two parallel metal plates onto a core and rolling them together. A spacer is provided between the metal plates. One of the metal plates has its edges turned up and down to form a through channel and a closed channel. The two ends of the closed channel are sealed by welding the edges together. The end face of the closed channel near the core is sealed by welding flat steel. Several cold medium flow holes are evenly opened on the side wall of the core near the closed channel.

8. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: A pipe box is installed on one side of the outer cylinder. The upper part of the pipe box has a cold side outlet, and the lower part has a hot side inlet. A blocking plate is installed inside the pipe box, which divides the inner cavity of the pipe box into an upper cavity and a lower cavity. The upper cavity is connected to the closed channel and the cold side outlet, respectively, and the lower cavity is connected to the through channel and the hot side inlet, respectively. A hot side outlet is installed in the middle of the large flat cover of the equipment located on the upper side of the outer cylinder. The hot side outlet is connected to the through channel.

9. A sealing and fastening device for the core structure of a detachable spiral plate heat exchanger according to claim 1, characterized in that: A hot-side drain port is provided on the large flat cover on one side of the upper end of the outer cylinder, and a hot-side discharge port is provided on the large flat cover on one side of the upper end of the outer cylinder. A cold-side drain port and a cold-side discharge port are also provided on the side wall of the outer cylinder. The cold-side drain port is located above the cold-side outlet, and the cold-side discharge port is located below the hot-side inlet. Both the hot-side drain port and the hot-side discharge port are connected to the through channel, and both the cold-side drain port and the cold-side discharge port are connected to the closed channel.

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