A leak-proof plate heat exchanger

Abstract

This invention relates to the field of plate heat exchanger technology and provides a leak-proof plate heat exchanger, comprising a frame, multiple heat exchange plates stacked on the frame, and a detection and alarm mechanism. Each heat exchange plate includes a plate and a collection pipe located at the bottom of the plate. The leak-proof plate heat exchanger provided by this invention, through the cooperation of an early warning groove and a collection pipe, can accurately detect minute leaks caused by hidden damage to the sealing strip. The coordinated use of the early warning groove, the confluence channel, and the collection pipe enables the directional collection and transport of the leaking medium, solving the problem of difficulty in detecting minute leaks in existing technologies and achieving early warning. This improves the timeliness and accuracy of detection, prevents minute leaks from developing into obvious leaks, and reduces potential production safety hazards.

Description

Technical Field

[0001] This invention relates to the field of plate heat exchanger technology, and more specifically to a leak-proof plate heat exchanger. Background Technology

[0002] Plate heat exchangers are widely used in various industrial fields such as chemical, metallurgical, HVAC, and food processing due to their advantages of high heat exchange efficiency, compact structure, and convenient assembly and disassembly. Their working principle is to achieve heat transfer between two or more media through multiple stacked heat exchange plates. The sealing performance between the heat exchange plates directly determines the operational stability and safety of the heat exchanger.

[0003] The sealing structure of existing plate heat exchangers typically involves creating sealing grooves in the heat exchange plates and installing sealing strips within these grooves to achieve sealing and isolation between adjacent plates, preventing media leakage. However, under long-term operating conditions, the sealing strips are susceptible to factors such as media corrosion, temperature cycling shocks, pressure fluctuations, and wear. This can lead to localized aging, micro-cracks, and other latent damage, causing minute leaks. These leaks are extremely small and highly concealed, making them difficult to detect initially. As the damage worsens, they gradually develop into obvious leaks, posing a potential safety hazard to production.

[0004] Currently, most methods for detecting leaks in plate heat exchangers involve regular manual inspections or sampling inspections using external testing equipment. These methods are extremely ineffective at identifying minute leaks, resulting in low detection efficiency, poor timeliness, and an inability to provide early warnings for minor leaks. Furthermore, the small amount of leaked media can slowly seep into the external environment or the internal gaps of the heat exchanger, causing hidden losses of valuable media and potentially leading to equipment corrosion and environmental pollution due to media accumulation. In severe cases, the leakage can even lead to sudden safety accidents as it expands. Some plate heat exchangers with leak warning functions have insufficient sensitivity in their warning structures, only able to detect relatively obvious leaks and failing to respond to minor leaks. Moreover, the warning structure design is complex and the warning coverage is limited. Even if a leak is detected, it is impossible to quickly and accurately locate the leaking plate, leading to delayed maintenance and further expanding the scope of damage.

[0005] Furthermore, existing heat exchanger plates lack proper isolation and flow guidance designs between the sealing groove and the early warning structure. Under normal operating conditions, the medium within the sealing groove can easily interfere with the early warning signal, leading to false alarms. Moreover, when faced with minor leaks caused by hidden damage to the sealing strip, the leaking medium cannot be quickly and stably collected and guided into the early warning mechanism, easily leading to warning failure due to medium diffusion or evaporation, further reducing the accuracy and reliability of minor leak detection. Therefore, there is an urgent need for a leak-proof plate heat exchanger that can accurately detect minor leaks, provide early warning, has a simple structure, and strong sealing stability to solve the aforementioned problems in existing technologies. Summary of the Invention

[0006] To overcome the above-mentioned defects, embodiments of the present invention provide a leak-proof plate heat exchanger, which solves the technical problem that plate heat exchangers in the related art cannot detect minute leaks in a timely manner.

[0007] At least one embodiment of the present invention provides a leak-proof plate heat exchanger, including a frame, a plurality of heat exchange plates stacked on the frame, and a detection alarm mechanism disposed on the frame and located at the bottom of the heat exchange plates; the heat exchange plates include:

[0008] The plates have a cavity for containing liquid medium between two adjacent plates. A sealing strip is embedded on the plate and located on the outer periphery of the cavity. A warning groove is also formed on the plate and located on the outer periphery of the sealing strip. The warning grooves of adjacent plates form a warning groove for containing liquid medium leaking from the sealing strip.

[0009] A liquid collection pipe is detachably installed at the bottom of the plate and connected to the warning groove for collecting liquid media in the warning groove. The detection alarm mechanism is installed on the liquid collection pipe for collecting leaked liquid media and issuing a leak alarm.

[0010] According to one embodiment of this application, the plate is provided with a partition protrusion located between the sealing strip and the warning groove. The partition protrusion is used to separate the sealing strip and the warning groove. The partition protrusion is also used to support the side wall of the sealing strip. The height of the partition protrusion is lower than the height of the plate surface. When the sealing strip fails, the liquid medium in the plate can flow into the warning groove through the partition protrusion.

[0011] According to one embodiment of this application, a confluence channel is provided at the bottom of the plate, and the confluence channel is connected to the warning groove.

[0012] According to one embodiment of this application, the plate is divided into a heat exchange zone and a non-heat exchange zone. A slot is provided on the partition protrusion located in the non-heat exchange zone. The slot connects the non-heat exchange zone with the warning groove. When the sealing strip of the non-heat exchange zone fails, the slot is used to guide the liquid medium into the warning groove.

[0013] According to one embodiment of this application, a sealing strip is provided on the plate, located on the outer periphery of the warning groove. The sealing strip is used to separate the warning groove from the outside. The height of the sealing strip protruding from the plate surface is the same as the height of the sealing strip protruding from the plate surface.

[0014] According to one embodiment provided in this application, the liquid collecting tube includes:

[0015] The tube body has its upper end inserted into the manifold channel and its other end extended to the outer side of the bottom of the plate. The tube body is provided with an inlet and an outlet, and the inlet is connected to the manifold channel.

[0016] A flow guide plate is disposed inside the tube, which divides the tube into a temporary storage chamber and a flow guide chamber. The temporary storage chamber is connected to the flow guide chamber. Liquid media entering the tube through the inlet can first flow into the temporary storage chamber, then overflow into the flow guide chamber, and then flow to the detection alarm mechanism through the flow guide chamber.

[0017] According to one embodiment of this application, the guide plate includes a guide section, an overflow section, and a partition section connected end to end in sequence. The partition section is horizontally disposed inside the pipe body. The overflow section is disposed on the guide section and extends upward. An overflow hole is opened in the middle of the overflow section. The guide section is disposed on the top of the partition section and is inclined. The guide section is used to guide the liquid medium into the temporary storage chamber.

[0018] According to one embodiment of this application, the tube body has a sampling port on its side wall above the temporary storage cavity, and the sampling port is connected to the temporary storage cavity.

[0019] According to one embodiment of this application, the frame is provided with a collection trough located below the collection pipe, and the collection trough is in communication with a plurality of collection pipes; the detection alarm mechanism includes:

[0020] An installation box is disposed below and communicates with the collection tank, and a sensor for sensing liquid media is provided inside the installation box;

[0021] An alarm controller is mounted on the mounting box and electrically connected to the sensor. The alarm controller is used to receive the detection signal from the sensor and issue an alarm signal.

[0022] According to one embodiment of this application, the liquid collection tube is made of transparent tube material.

[0023] This invention provides a leak-proof plate heat exchanger. Compared to existing technologies, when the plate heat exchanger is running, the sealing strips achieve sealing and isolation between adjacent plates. When the sealing strips fail due to aging, micro-cracks, or other reasons, resulting in minor leaks, the liquid medium inside the plate leaks through the failure point to the outer warning groove. The warning groove guides the leaked liquid medium to a connecting channel, which further guides the medium to the bottom collection pipe for collection. Once the accumulated medium in the collection pipe is detected by the detection alarm mechanism, the mechanism activates an alarm to indicate that a leak has occurred in the plate.

[0024] This device can accurately detect minute leaks caused by hidden damage to the sealing strip. Through the cooperation of the warning groove and the collection pipe, it achieves directional collection and transportation of the leaked medium, solving the problem of difficulty in detecting minute leaks in existing technologies and enabling early warning. The overall structure of the device is simple, allowing for direct stamping during plate processing without the need for multiple additional machining steps. Furthermore, the one-piece stamping reduces the risk of plate breakage. The detachable collection pipe facilitates maintenance, and the detection and alarm mechanism acts directly on the collection pipe, improving the timeliness and accuracy of detection, preventing minute leaks from developing into significant leaks, and reducing production safety hazards. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of a leak-proof plate heat exchanger provided in an embodiment of the present invention;

[0027] Figure 2 This is an embodiment of the present invention. Figure 1 Front view of the middle plate;

[0028] Figure 3 This is an embodiment of the present invention. Figure 1 Schematic diagram of the middle plate;

[0029] Figure 4 This is an embodiment of the present invention. Figure 1 A schematic diagram of the structure of the central sealing groove, the partition protrusion, and the warning groove;

[0030] Figure 5 This is an embodiment of the present invention. Figure 1 A magnified view of a section at point A in the middle;

[0031] Figure 6 This is a schematic diagram of the internal structure of the liquid collection tube of the present invention.

[0032] In the diagram: 100, frame; 200, heat exchange plate; 1, plate; 101, sealing groove; 102, warning groove; 103, confluence channel; 104, heat exchange zone; 105, non-heat exchange zone; 106, slot; 2, sealing strip; 3, detection and alarm mechanism; 31, mounting box; 4, liquid collection pipe; 401, liquid inlet; 402, liquid outlet; 41, pipe body; 42, guide plate; 421, guide section; 422, overflow section; 423, partition section; 424, overflow hole; 43, temporary storage chamber; 44, guide chamber; 45, sampling port; 5, sealing strip; 6, partition protrusion; 7, collection groove. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application 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 limitations on this application.

[0036] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those illustrated or described herein.

[0037] To make the drawings concise and easy to understand, some drawings only show one of the components with the same structure or function, or only one of them is marked. In this article, "one" not only means "only one", but can also mean "more than one", and "several" includes "two" and "more than two".

[0038] Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. It is understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0039] First, it should be noted that a plate heat exchanger is a high-efficiency heat exchange device composed of a series of corrugated thin metal plates stacked together. The plates (1) are separated by sealing gaskets to form thin rectangular channels. Common types include frame-type (detachable) and brazed type. The plates (1) are often herringbone-shaped, horizontally straight corrugated, or dovetail-shaped. Its working principle involves allowing hot and cold fluids to flow on both sides of the plates (1) in a counter-current, co-current, or cross-flow manner, without mixing, and efficiently transferring heat through the plates (1). The heat transfer coefficient is 3-5 times higher than that of a tubular heat exchanger, and the heat recovery rate can reach over 90%. It boasts advantages such as compact structure, a footprint only 1 / 3 that of a tubular heat exchanger, low metal consumption, low heat loss, easy disassembly and cleaning, and flexible adjustment of the heat exchange area by adding or removing plates (1). It can handle media ranging from water to high-viscosity liquids and even media containing suspended particles, and is widely used in heating, cooling, and condensation processes in chemical, food processing, refrigeration, HVAC, and shipbuilding industries.

[0040] However, plate heat exchangers generally have limitations such as poor resistance to high temperatures and pressures, and narrow flow channels that are prone to blockage. This is because the sealing of plate heat exchangers relies primarily on the compression sealing of gaskets (sealing strips 2) between the plates. Therefore, if any gasket fails, the entire plate heat exchanger needs to be shut down for maintenance. However, in actual operation, even minor leaks in the gaskets are difficult to detect in time. By this point, the operating efficiency and heat exchange effect of the plate heat exchanger have already decreased. Therefore, early detection of leaks allows for timely maintenance and reduces unnecessary losses. It should also be noted that current manual inspection is not only difficult to detect leaks, but maintenance personnel cannot continuously monitor the heat exchanger. Therefore, a device capable of automatically detecting even minor leaks is needed.

[0041] like Figures 1-6The diagram illustrates a leak-proof plate heat exchanger according to an embodiment of the present invention. The plate heat exchanger consists of a frame 100, multiple heat exchange plates 200 stacked on the frame 100, and a detection and alarm mechanism 3. Each heat exchange plate 200 includes a plate 1 and a liquid collection pipe 4 located at the bottom of the plate 1. A sealing groove 101 for accommodating a sealing strip 2 is formed on the plate 1. A warning groove 102 is formed at the position of the plate 1 outside the sealing groove 101. A flow channel 103 is formed at the bottom of the plate 1, and the flow channel 103 is in communication with the warning groove 102. The liquid collection pipe 4 is detachably installed at the bottom of the plate 1, specifically by means of insertion, bonding, snap-fit, or threaded connection. The liquid collection pipe 4 is connected to the flow channel 103 and is specifically used to collect the liquid medium flowing through the flow channel 103. The detection and alarm mechanism 3 is mounted on the frame 100 and can detect the liquid medium within the liquid collection pipe 4.

[0042] Specifically, when the liquid medium in the plate 1 leaks into the warning groove 102 through the failure of the sealing strip 2, the warning groove 102 is used to guide the liquid medium through the manifold 103 to the collection pipe 4 for collection. The detection and alarm mechanism 3 can detect the liquid medium in the collection pipe 4 to provide an early warning of the leakage of the plate 1.

[0043] In the above scheme, when the plate heat exchanger is running, the sealing strip 2 is placed in the sealing groove 101 to achieve sealing and isolation between adjacent plates 1. When the sealing strip 2 fails due to aging, micro-cracks, or other reasons, resulting in minor leakage, the liquid medium inside the plate 1 will leak through the failure point to the warning groove 102 on the outside. The warning groove 102 guides the leaked liquid medium to the connecting channel 103, which further guides the medium to the bottom collection pipe 4 for collection. After the medium accumulated in the collection pipe 4 is detected by the detection alarm mechanism 3, the detection alarm mechanism 3 activates the warning, indicating that there is a leak in the plate 1.

[0044] Therefore, this device can accurately detect minute leaks caused by hidden damage to the sealing strip 2. Through the cooperation of the warning groove 102, the manifold channel 103, and the collection pipe 4, it achieves directional collection and transportation of the leaked medium, solving the problem of difficult detection of minute leaks in existing technologies and enabling early warning. The overall structure of the device is simple, allowing for direct stamping during the processing of the plate 1 without additional processing steps. Furthermore, the one-piece stamping reduces the risk of plate 1 breakage. The collection pipe 4 is detachable for easy maintenance, and the detection and alarm mechanism 3 acts directly on the collection pipe 4, improving the timeliness and accuracy of detection, preventing minute leaks from developing into obvious leaks, and reducing production safety hazards.

[0045] Furthermore, a partition protrusion 6 is provided between the sealing groove 101 and the warning groove 102 of the plate 1. It should be noted that after two adjacent plates 1 are installed by compression, the top surface of the partition protrusion 6 will not abut against the back of the other plate 1; a certain gap will remain between them. The partition protrusion 6 of this device effectively separates the sealing groove 101 and the warning groove 102, and also provides support for the sidewall of the sealing strip 2. The partition protrusion 6 and the plate 1 are an integrated structure, arranged between the outer edge of the sealing groove 101 and the inner edge of the warning groove 102, forming a separation barrier between them.

[0046] In the above scheme, under normal operating conditions, the partition protrusion 6 isolates the medium in the sealing groove 101 from the warning groove 102. Since the sealing strip 2 needs to seal and block the liquid in the plate 1, without the partition protrusion 6, the sealing strip 2 cannot be effectively blocked, leading to its failure. The partition provides support to the sidewall of the sealing strip 2, enhancing its installation stability within the sealing groove 101 and reducing damage from pressure fluctuations and temperature shocks. When leakage occurs due to sealing strip 2 failure, the medium breaks through the sealing strip 2, first contacting the partition protrusion 6, and then flowing into the warning groove 102, ensuring that the leaking medium is directed into the detection channel.

[0047] By setting the partition protrusion 6, the support for the sealing strip 2 can be strengthened, the stability of the sealing structure can be enhanced, and the aging and damage rate of the sealing strip 2 can be slowed down. At the same time, it provides a transition guide for the leaked medium, avoids the direct diffusion of the medium, and further ensures that even small leaks can be stably collected.

[0048] Furthermore, the height of the partition protrusion 6 is lower than the surface height of the plate 1. Its overall height setting can both meet the support requirements of the side wall of the sealing strip 2 and ensure that the leaked medium can pass smoothly after the sealing strip 2 fails. The top of the partition protrusion 6 maintains a certain height difference with the plate surface, so as not to affect the sealing of the adjacent plates 1.

[0049] In the above scheme, when the sealing strip 2 is working normally, the partition protrusion 6 provides stable support for the sealing strip 2 based on its own height and structure, while maintaining the separation between the sealing groove 101 and the warning groove 102. When the sealing strip 2 suffers localized aging, micro-cracks, or other hidden damage that causes minor leakage, the leaked trace medium can easily pass over the partition protrusion 6, which is lower than the plate surface, under pressure and flow into the warning groove 102. The partition protrusion 6 will not obstruct the leakage medium from entering the detection channel due to its excessive height. This scheme balances the stability of the sealing strip 2's support with the flowability of the leaked medium, solving the problem of existing structures where the partition components hinder the collection of minor leaked medium. It ensures that even extremely small amounts of leaked medium can smoothly enter the warning system, significantly improving the detection sensitivity of minor leaks and providing reliable assurance for early warning.

[0050] Furthermore, the plate 1 is divided into a heat exchange zone 104 and a non-heat exchange zone 105. A slot 106 is provided on the partition protrusion 6 located in the non-heat exchange zone 105. The slot 106 is funnel-shaped and directly connects the sealing groove 101 of the non-heat exchange zone 105 with the warning groove 102. The opening position of the slot 106 is adapted to the arrangement trajectory of the sealing strip 2 in the non-heat exchange zone 105 to ensure that the leaked medium can flow in accurately.

[0051] In the above scheme, because the sealing strip 2 in the non-heat exchange zone 105 is mostly a triangular reinforced structure, the sealing strip 2 in the non-heat exchange zone 105 can still maintain a good sealing effect even without the support of the partition protrusion 6. Moreover, the sealing strip 2 in the heat exchange zone 104 is in direct contact with the liquid medium and is more prone to damage and aging. However, the sealing strip 2 in the non-heat exchange zone 105, especially the strips in the non-heat exchange zone 105 between the triangular reinforced structure areas, are mostly multiple seals. If leakage occurs here, it may not be detected in time, which may eventually lead to a greater risk of leakage. Therefore, when the sealing strip 2 in the non-heat exchange zone 105 fails and leaks, the leaking medium does not need to cross the partition protrusion 6 and can directly flow into the warning groove 102 through the groove 106, avoiding the accumulation and diffusion of the medium in the gap of the non-heat exchange zone 105. When the sealing strip 2 of the heat exchange zone 104 fails, the leaked medium can still pass over the partition protrusion 6 and enter the warning groove 102, achieving full coverage collection of the leaked medium in the heat exchange zone 104 and the non-heat exchange zone 105, and then be introduced into the liquid collection pipe 4 through the manifold channel 103.

[0052] To address the difficulty in collecting leaked media in the non-heat exchange zone 105, a directional flow is achieved through the slot 106, improving the collection efficiency and speed of minute leaks in the non-heat exchange zone 105. This enables full-area leak detection coverage of plate 1, avoiding omissions due to the concealed nature of leaks in the non-heat exchange zone 105, and further optimizing the comprehensiveness and accuracy of leak detection.

[0053] Furthermore, a sealing strip 5 is provided on the plate 1 at the position outside the warning groove 102. The height of the sealing strip 5 protruding from the plate surface is consistent with the height of the sealing strip 2 protruding from the plate surface. The sealing strip 5 is arranged around the warning groove 102 to form an isolation barrier between the warning groove 102 and the external environment, and does not affect the tight fit of the adjacent plates 1.

[0054] In the above scheme, during heat exchanger operation, the sealing strip 5 is in close contact with the adjacent plates 1, completely isolating the warning groove 102 from the outside world. This prevents external impurities from entering the warning groove 102 and interfering with detection, while also preventing the leakage medium within the warning groove 102 from evaporating or seeping into the external environment. Because the sealing strip 5 and the sealing strip 2 are at the same height, it ensures uniform force when the adjacent plates 1 are in contact, guaranteeing overall sealing performance without affecting the normal operation of the warning groove 102. This effectively prevents the diffusion and evaporation of the leakage medium and interference from external impurities, improving the stability and accuracy of leakage medium collection and detection. It avoids hidden losses and environmental pollution caused by trace amounts of leakage medium, while enhancing the overall sealing performance between the plates 1, reducing additional damage caused by uneven contact, and extending the equipment's service life.

[0055] In a specific embodiment, the liquid collecting pipe 4 consists of a pipe body 41 and a guide plate 42. One end of the pipe body 41 is inserted into the manifold 103, and the other end extends to the outer side of the bottom of the plate 1. The pipe body 41 has an inlet 401 and an outlet 402, and the inlet 401 is in communication with the manifold 103. The guide plate 42 is installed inside the pipe body 41, dividing the pipe body 41 into a temporary storage chamber 43 and a guide chamber 44. The temporary storage chamber 43 and the guide chamber 44 are in communication with each other. The inlet 401 is set corresponding to the temporary storage chamber 43 to ensure that the medium enters the temporary storage chamber 43 first.

[0056] In the above scheme, the leaked medium enters the temporary storage chamber 43 of the pipe body 41 through the inlet 401 via the manifold 103. The temporary storage chamber 43 temporarily stores the small amount of leaked medium. When the medium in the temporary storage chamber 43 accumulates to a certain amount, it overflows into the interconnected guide chamber 44. The guide chamber 44 guides the medium to flow steadily towards the outlet 402, and then delivers it to the detection and alarm mechanism 3, realizing the buffered collection and stable delivery of the leaked medium.

[0057] The advantage of this design is that, since multiple collection pipes 4 of this device are connected to a single collection tank 7, when an alarm signal is triggered, maintenance personnel can determine which two plates 1 are leaking by observing whether liquid medium is present in the temporary storage chamber 43. Furthermore, the temporary storage chamber 43 allows for the accumulation of minute leaks, preventing the detection alarm mechanism 3 from failing to detect leaks due to insufficient medium volume, thus improving the ability to identify minute leaks. The partition design of the guide plate 42 ensures more stable medium flow, preventing medium splashing or backflow from interfering with detection. Simultaneously, the removable pipe body 41 facilitates cleaning and maintenance, reducing equipment operation and maintenance costs.

[0058] refer to Figure 6In some embodiments, the guide plate 42 is composed of a guide section 421, an overflow section 422, and a partition section 423 connected end to end in sequence. The partition section 423 is horizontally installed inside the pipe body 41. The overflow section 422 is disposed on the partition section 423, and an overflow hole 424 is opened in the middle of the overflow section 422. The partition section 423, the inner wall of the pipe body 41, and the plate area of ​​the overflow section 422 at the lower edge of the overflow hole 424 together form a temporary storage cavity 43. The guide section 421 is disposed on the top of the partition section 423 and is inclined to guide the medium into the temporary storage cavity 43.

[0059] In the above scheme, after the leaking medium enters the pipe body 41 through the inlet 401, it flows precisely into the temporary storage chamber 43 under the guidance of the inclined guide section 421. As the medium accumulates in the temporary storage chamber 43, the liquid level gradually rises. When the liquid level reaches the height of the overflow hole 424, the medium overflows smoothly through the overflow hole 424 to the guide chamber 44. The guide chamber 44, relying on the structure of the pipe body 41 and the guiding effect of the guide section 421, stably guides the medium to the outlet 402 and delivers it to the detection alarm mechanism 3. The inclined guide section 421 achieves precise guidance of the medium, avoiding the medium from adhering to and remaining on the inner wall of the pipe body 41, and improving the medium collection efficiency. The setting of the overflow hole 424 precisely controls the timing of the medium overflow, ensuring that a sufficient amount of medium accumulates in the temporary storage chamber 43 for detection, further improving the detection sensitivity and stability, and preventing false triggering or leakage triggering of early warning due to trace amounts of medium.

[0060] Furthermore, a sampling port 45 is provided on the side wall of the pipe body 41 above the temporary storage chamber 43. The sampling port 45 is in communication with the temporary storage chamber 43 and is equipped with a suitable sealing structure to ensure that the medium will not leak under normal operating conditions, while also facilitating sampling. By taking a sample through the sampling port 45, the temperature of the sample can be measured to determine whether it is a cold or hot liquid medium, and the location of the sealing strip 2 near which it has failed can be quickly determined, facilitating rapid troubleshooting and repair.

[0061] Furthermore, when the detection alarm mechanism 3 issues a warning signal, the sealing structure at the sampling port 45 can be opened to extract a sample of the leaked medium from the temporary storage chamber 43 for analysis of the medium's composition and contamination level. During sampling, the medium in the temporary storage chamber 43 can still overflow normally through the overflow hole 424 to the guide chamber 44, without affecting the continuous operation of the detection alarm mechanism 3. After sampling, closing the sealing structure will restore normal operation. This facilitates the rapid acquisition of leaked medium samples by personnel, accurately determining the type of leaked medium, and providing a basis for developing maintenance plans. The sampling process does not interrupt the early warning detection, ensuring continuous monitoring of the leak status, preventing the leak from expanding during maintenance, and improving the targetedness and efficiency of equipment maintenance.

[0062] Furthermore, the detection and alarm mechanism 3 includes a collection tank 7, a mounting box 31, and an alarm controller. The collection tank 7 is mounted on the frame 100 and located below all the liquid collection pipes 4, maintaining communication with all the liquid collection pipes 4. A collection chamber is provided in the center of the bottom surface of the collection tank 7 for collecting the leaked medium transported by each liquid collection pipe 4. The mounting box 31 is connected to the collection chamber, and a sensor for sensing liquid is installed inside the box. The alarm controller is mounted on the mounting box 31 and establishes an electrical connection with the sensor.

[0063] In the above scheme, the leaked medium in each collection pipe 4 flows into the collection tank 7 below through the outlet 402. The medium gathers in the collection tank 7 and flows to the collection chamber at the bottom. When the medium in the collection chamber comes into contact with the sensor, the sensor senses the liquid signal and transmits it to the alarm controller. The alarm controller converts the detection signal into an alarm signal and issues it to remind the staff that there is a leak.

[0064] This system enables centralized collection and detection of leaking media from multiple heat exchange fins (up to 200 mm), simplifying the detection structure and reducing equipment manufacturing costs. The collection chamber design ensures stable contact between the leaking media and the sensor, improving detection reliability. The alarm controller quickly converts signals to issue early warnings, solving the problem of delayed warnings in existing technologies and allowing more time for early leak handling.

[0065] In this embodiment, the sensor is adapted to meet the requirements of accurate capture of trace leakage media, corrosion resistance, high temperature resistance, and compatibility with the collection chamber structure of the collection tank 7. It adopts a complementary combination of capacitive liquid level sensor (contact type, main use) and photoelectric liquid level sensor (non-contact type, backup), both of which are installed in the mounting box 31 at the bottom of the collection tank 7 in the corresponding media collection area, to ensure reliable detection of milliliter-level trace leakage media, and is suitable for harsh working conditions in chemical, metallurgical and other fields.

[0066] The capacitive level sensor uses Hastelloy or titanium alloy electrodes and PTFE shell, which can withstand high temperatures of -40℃ to 200℃, high pressure of ≤1.6MPa, and various corrosive media. It has no mechanical wear and a detection accuracy of 0.1mm. Its electrodes and the inner wall of the collection chamber (grounded) form the two poles of a capacitor. Under normal operating conditions, it maintains the reference no-load capacitance value. When the leaking medium comes into contact with the electrode, the medium changes the capacitance value as a dielectric. The built-in module converts it into a PNP / NPN switch signal and transmits it to the alarm controller. It also has temperature compensation function and adjustable threshold (preset 1~2mm liquid level) to avoid false triggering. The photoelectric level sensor is based on the principle of infrared scattering. The probe is sealed and installed on the outside of the mounting box 31 without contact. It is suitable for high viscosity and easily crystallizing media and can avoid the problems of adhesion and corrosion failure of contact sensors. The infrared light emitted by the probe has stable reflected light intensity when there is no medium. When the medium reaches the preset liquid level, scattering occurs, causing a sudden change in light intensity. A synchronous switch signal is output within ≤5ms, forming redundant detection with the main sensor. When the signal is inconsistent, a fault alarm is triggered to prompt maintenance.

[0067] Two sensors are integrated in the mounting box 31, which is sealed and connected to the collection chamber of the collection tank 7. The capacitive electrode is vertically inserted into the center of the collection chamber, and the photoelectric probe corresponds to the side wall of the liquid level trigger point. The detection threshold is uniformly calibrated by the alarm controller. During operation, the two sensors run synchronously. If either sensor triggers a signal, the early warning process is initiated. If both signals are synchronized, the leak is confirmed to be valid. If a single signal triggers, it is determined to be a suspected leak and a graded early warning is issued. The alarm controller uses a PLC-type intelligent controller, which is core-compatible with multi-signal processing, hierarchical early warning, and remote linkage requirements. The shell is made of waterproof, dustproof, and corrosion-resistant material. It has a built-in signal acquisition module, logic processing unit, and communication module, which can accurately receive dual sensor switch signals and determine the leakage type (effective leakage, suspected leakage, sensor failure) through logic calculation. It supports local audible and visual early warning and remote signal push. Locally, a high-decibel buzzer (volume ≥85dB) and red, yellow, and green indicator lights distinguish the warning level (red for effective leakage, yellow for suspected leakage, and orange for sensor failure). Remotely, the warning information is pushed to the central control system via RS485 / Modbus protocol, along with the leakage occurrence time and sensor status data. It supports manual reset and automatic recording of warning logs, and has threshold calibration and fault self-checking functions. Parameters can be adjusted remotely via panel buttons or the central control system to ensure coordination with the overall leak prevention system of the heat exchanger, achieving accurate early warning of micro-leakage, rapid fault tracing, and convenient operation and maintenance.

[0068] Furthermore, the liquid collecting tube 4 is made of transparent tube material, which has corrosion resistance and high temperature resistance, making it suitable for the working conditions of plate heat exchangers. At the same time, it maintains good light transmittance, allowing direct observation of the accumulation and state of the medium inside the tube body 41.

[0069] In the above solution, when a minor leak occurs in the sealing strip 2, the medium enters the transparent collection pipe 4 through the manifold 103. Workers can directly observe whether there is medium accumulation, the amount accumulated, and the state of the medium inside the pipe 41 through the transparent pipe. Combined with the warning signal from the detection and alarm mechanism 3, the specific leaking heat exchange plate 200 can be quickly identified, facilitating precise location. This achieves rapid and accurate location of the leak, solving the problem of delayed maintenance caused by difficulty in locating the plate 1 after a leak in existing technologies, shortening maintenance time, and reducing losses caused by the expansion of the leak. The transparent material facilitates daily inspection and observation, and can help determine whether there are abnormalities such as blockages in the collection pipe 4, improving the convenience of equipment operation and maintenance.

[0070] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A leak-tight plate heat exchanger, c h a r a c t e r i s e d in that Includes a frame (100), a plurality of heat exchange fins (200) stacked on the frame (100), and a detection alarm mechanism (3) disposed on the frame (100) and located at the bottom of the heat exchange fins (200); the heat exchange fins (200) include: Plate (1), with a receiving cavity for containing liquid medium formed between two adjacent plates (1), a sealing strip (2) is embedded on the plate (1) and located on the outer periphery of the receiving cavity, and a warning groove (102) is also provided on the plate (1) located on the outer periphery of the sealing strip (2), and the warning groove (102) of the adjacent plates (1) forms a warning groove for containing liquid medium leaking from the sealing strip (2); The liquid collection pipe (4) is detachably installed at the bottom of the plate (1) and connected to the warning groove for collecting the liquid medium in the warning groove (102). The detection alarm mechanism (3) is installed on the liquid collection pipe (4) for collecting the leaked liquid medium and issuing a leak alarm. The plate (1) is provided with a partition protrusion (6) located between the sealing strip (2) and the warning groove (102). The partition protrusion (6) is used to separate the sealing strip (2) and the warning groove (102). The partition protrusion (6) is also used to support the side wall of the sealing strip (2). The height of the partition protrusion (6) is lower than the height of the plate surface. When the sealing strip (2) fails, the liquid medium in the plate (1) can flow into the warning groove (102) through the partition protrusion (6).

2. The leak-proof plate heat exchanger according to claim 1, characterized in that, The bottom of the plate (1) is provided with a confluence channel (103), which is connected to the warning groove (102).

3. The leak-proof plate heat exchanger according to claim 1, characterized in that, The plate (1) is divided into a heat exchange zone (104) and a non-heat exchange zone (105). A slot (106) is provided on the partition protrusion (6) located in the non-heat exchange zone (105). The slot (106) connects the non-heat exchange zone (105) with the warning groove (102). When the sealing strip (2) of the non-heat exchange zone (105) fails, the slot (106) is used to guide the liquid medium into the warning groove (102).

4. A leak-proof plate heat exchanger according to claim 1, characterized in that, The plate (1) is provided with a sealing strip (5) located on the outer periphery of the warning groove (102). The sealing strip (5) is used to separate the warning groove (102) from the outside. The height of the sealing strip (5) protruding from the plate surface is the same as the height of the sealing strip (2) protruding from the plate surface.

5. A leak-proof plate heat exchanger according to claim 2, characterized in that, The liquid collecting tube (4) includes: The tube body (41) is inserted into the manifold (103) at its upper end and extends to the outer side of the bottom of the plate (1) at the other end. The tube body (41) is provided with an inlet (401) and an outlet (402). The inlet (401) is connected to the manifold (103). A guide plate (42) is disposed inside the tube body (41). The guide plate (42) divides the tube body (41) into a temporary storage chamber (43) and a guide chamber (44). The temporary storage chamber (43) is connected to the guide chamber (44). The liquid medium entering the tube body (41) through the inlet (401) can first flow into the temporary storage chamber (43), then overflow to the guide chamber (44), and then flow to the detection alarm mechanism (3) through the guide chamber (44).

6. A leak-proof plate heat exchanger according to claim 5, characterized in that, The guide plate (42) includes a guide section (421), an overflow section (422), and a partition section (423) connected end to end in sequence. The partition section (423) is horizontally arranged inside the pipe body (41). The overflow section (422) is arranged on the guide section (421) and extends upward. An overflow hole (424) is opened in the middle of the overflow section (422). The guide section (421) is arranged on the top of the partition section (423) and the guide section (421) is inclined. The guide section (421) is used to guide the liquid medium into the temporary storage chamber (43).

7. A leak-proof plate heat exchanger according to claim 5, characterized in that, The tube body (41) has a sampling port (45) on its side wall above the temporary storage cavity (43), and the sampling port (45) is connected to the temporary storage cavity (43).

8. A leak-proof plate heat exchanger according to claim 1, characterized in that, The frame (100) is provided with a collection tank (7) located below the collection pipe (4), and the collection tank (7) is connected to multiple collection pipes (4); the detection alarm mechanism (3) includes: The mounting box (31) is located below the collection tank (7) and communicates with the collection tank (7). The mounting box (31) is equipped with a sensor for sensing liquid media. An alarm controller is mounted on the mounting box (31) and electrically connected to the sensor. The alarm controller is used to receive the detection signal from the sensor and issue an alarm signal.

9. A leak-proof plate heat exchanger according to claim 1, characterized in that, The liquid collection tube (4) is made of transparent tube material.

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