Pipeline overcurrent and overvoltage protection device, flame arrester and rectifier

Abstract

The invention relates to the technical field of fuel gas pipeline safety protection equipment, and discloses a pipeline overcurrent and overvoltage protection device, a flame arrester and a rectifier, the device comprises a shell, one end of the shell is provided with a gas inlet, the other end of the shell is provided with a gas outlet, a first cavity and a second cavity are formed in the shell, and a first hole and a second hole are formed between the first cavity and the second cavity; the sealing element is slidably arranged in the shell, and one end of the sealing element is connected with the first spring; the pressure release valve is arranged on the side wall of the shell, the inner end of the pressure release valve extends to the second hole, and the pressure release valve is used for controlling opening and closing of the second hole; when the upstream air pressure of the shell is higher than the downstream air pressure preset value, the sealing piece is pushed by airflow to overcome the acting force of the first spring to plug the first hole and keep the plugging state, and downstream conveying of air is cut off. The pipeline over-current and over-voltage protection device is integrated in the flame arrester and the rectifier, so that gas conveying can be cut off when over-voltage and over-current situations occur in the pipeline while flame retardance and rectification can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of gas pipeline safety protection equipment, and in particular to a pipeline overcurrent and overpressure protection device, a flame arrester and a rectifier. Background Art

[0002] During gas combustion, flame arresters are typically installed on pipelines to prevent flashbacks, potentially resulting from a loss of pressure and the spread of flames throughout the pipeline network. However, flame arresters cannot detect and shut off open leaks caused by overpressure, overflow, or pipeline rupture.

[0003] Currently, the primary method for preventing gas accidents caused by gas overpressure and overflow is to install pressure sensors and emergency shut-off valves on gas pipelines. The pressure sensors measure the gas pressure, and when the pressure is too high or too low, a controller sends a command to the shut-off valve to cut off the gas. However, this method has the following drawbacks: 1. A power supply is required: implementation is difficult and costly in locations where power distribution is unsuitable; 2. A high failure rate: A malfunction or power loss in the pressure sensor or controller can cause the shut-off function to fail or even malfunction; 3. High cost: A high-quality pressure transmitter, controller, and emergency shut-off valve can cost at least tens of thousands of yuan, and even over 100,000 yuan for large-caliber systems.

[0004] Furthermore, to ensure safe gas transportation in pipelines, ultrasonic flowmeters are often used to monitor gas flow in real time. However, in actual industrial applications, a number of factors severely restrict the full performance of ultrasonic flowmeters. For one thing, the prevalence of elbows, valves, joints, and other fittings in pipeline systems can cause extremely uneven flow velocity distribution within the gas flow. To stabilize the gas flow pattern and ensure measurement accuracy, a straight pipe section of at least 10 pipe diameters is typically installed upstream of the flowmeter, and at least 5 pipe diameters downstream. However, in some space-constrained industrial sites, the installation of excessively long straight pipe sections is often difficult, significantly limiting the application of ultrasonic flowmeters. Furthermore, when regulating valves commonly used in industrial production operate, gas throttling converts mechanical energy into acoustic energy, generating high-frequency noise. This noise, with a frequency close to the operating frequency of the ultrasonic flowmeter, can severely interfere with the reception and processing of ultrasonic signals, significantly reducing the flowmeter's measurement accuracy and, in extreme cases, even rendering it inoperable. The traditional method of eliminating interference by relying on noise suppression algorithms is difficult to effectively suppress this type of noise caused by throttling components in the pipeline. Summary of the Invention

[0005] The present invention is made to solve the above technical problems. One of its purposes is to provide a pipeline overcurrent and overpressure protection device that can cut off the gas when overpressure or overcurrent occurs in the pipeline.

[0006] Another object of the present invention is to provide a flame arrester that can quickly cut off the gas when the gas pressure in the pipeline is too high, too low, or the gas pipeline is ruptured, while achieving the fire arresting function.

[0007] Another object of the present invention is to provide a rectifier that can cut off the gas when overpressure or overflow occurs in the pipeline, and can also rectify the airflow in the pipeline to achieve noise reduction, create a stable measurement environment for the ultrasonic flowmeter on the pipeline, and indirectly improve the measurement accuracy of the flow.

[0008] According to one embodiment of the present invention, a pipeline overcurrent and overpressure protection device is provided, comprising: a shell, one end of which is provided with an air inlet, the other end of which is provided with an air outlet, a first cavity and a second cavity formed therein, a first hole and a second hole formed between the first cavity and the second cavity; a sealing member slidably arranged in the shell, one end of which is connected to a first spring; a pressure relief valve arranged on the side wall of the shell, the inner end of which extends to the second hole, for controlling the opening and closing of the second hole; wherein when the difference between the upstream air pressure and the downstream air pressure of the shell is less than a preset value, the seal is subjected to the thrust of the airflow and the force of the first spring, which are equal or substantially equal, and the seal maintains a certain distance from the first hole to keep the gas transported downstream; when the upstream air pressure of the shell is higher than the preset value of the downstream air pressure, the seal is pushed by the airflow to overcome the force of the first spring to seal on the first hole and maintain a sealed state, thereby cutting off the gas transport to the downstream.

[0009] As an embodiment, a guide rod is fixedly provided in the housing, and the sealing member is slidably provided on the guide rod.

[0010] As an embodiment, the sealing member is a sphere sleeved on the guide rod.

[0011] As an embodiment, the first spring is a compression spring arranged downstream of the seal and sleeved on the guide rod, and its end away from the seal is fixed to the guide rod; or the first spring is a tension spring arranged upstream of the seal and sleeved on the guide rod, and its end away from the seal is fixed to the guide rod.

[0012] As an embodiment, the pressure relief valve includes: a valve seat, in which an exhaust hole connected to the second hole is formed; a pressure relief push rod, slidably arranged in the valve seat and the side wall of the shell; a sealing gasket, sleeved on the pressure relief push rod; a second spring, arranged in the valve seat, applying a force to the pressure relief push rod, so that the sealing gasket blocks the exhaust hole; wherein, when the pressure relief push rod slides into the shell, the sealing gasket releases the blockage of the exhaust hole.

[0013] As an embodiment, the exhaust hole includes an exhaust inlet, an exhaust outlet and a pilot hole, the exhaust inlet is connected to the second hole, the exhaust outlet is connected to the second cavity close to the downstream, and the pilot hole is arranged between the exhaust inlet and the exhaust outlet; the pressure relief push rod is subjected to the force of the second spring to drive the sealing gasket to seal on the pilot hole.

[0014] As an embodiment, the pressure relief valve includes: a screw rod, threadedly connected to the side wall of the shell; a plug, fixedly arranged at the inner end of the screw rod, opposite to the second hole; wherein when the screw rod rotates and moves toward the inside of the shell, the plug blocks the second hole; when the screw rod rotates and moves toward the outside of the shell, the plug releases the blockage of the second hole.

[0015] According to one embodiment of the present invention, a flame arrester is provided, comprising: the pipeline overcurrent and overpressure protection device as described above; a first flame arrester net fixed in the first cavity; and a second flame arrester net fixed in the second cavity.

[0016] As an embodiment, when a guide rod is provided in the shell, both ends of the guide rod are fixed to the first fire-blocking net and the second fire-blocking net respectively.

[0017] As an embodiment, the diameter of the middle portion of the flame arrester is larger than the diameters of the air inlet and the air outlet.

[0018] According to one embodiment of the present invention, a rectifier is provided, comprising: the pipeline overcurrent and overpressure protection device as described above; a downstream noise reduction block, which is fixedly arranged in the second cavity located downstream and has a mesh structure; a flow stabilizing tube bundle, which is arranged downstream of the downstream noise reduction block and is a plurality of tubes filled in the second cavity, and the tubes are arranged along the length direction of the second cavity.

[0019] As an embodiment, the rectifier further includes: an upstream noise reduction block, which is fixedly arranged in the first cavity located upstream, and a noise reduction block filter is provided in the middle thereof opposite to the air inlet.

[0020] As an embodiment, when a guide rod is provided in the shell, one end of the guide rod is fixed to the upstream noise reduction block.

[0021] As an embodiment, the upstream noise reduction block further includes a support rod, one end of which is connected to the noise reduction block filter screen, and the other end of which is connected to the inner wall of the first cavity.

[0022] According to the above description and practice, the pipeline overflow and overpressure protection device of the present invention utilizes a first spring and a sliding seal in combination within a housing. When gas flows within the device, the thrust of the airflow and the force of the first spring on the seal are equal or substantially equal, and the seal maintains a certain distance from the first hole, preventing gas from flowing downstream. When the upstream air pressure of the housing exceeds a preset downstream air pressure, the seal, pushed by the airflow, overcomes the force of the first spring and blocks the first hole, maintaining the blockage and cutting off gas flow downstream. Therefore, when the device is applied to a gas transmission pipeline, if an overpressure condition occurs upstream of the pipeline or an overflow condition occurs downstream, the seal slides onto the first hole, cutting off gas flow downstream and placing the pipeline in a safe state. Subsequent adjustment of the pressure relief valve can equalize or approximate the air pressure upstream and downstream of the device, and then the first spring removes the seal from the first hole, restoring gas flow. With the help of this pipeline overflow and overpressure protection device, it is possible to ensure that the pipeline in which it is located can safely transport gas. The pipeline overcurrent and overpressure protection device does not require power supply during the entire working process, and the device has a simple structure, is not prone to failure, has good stability, will not cause miscutting, and has a low production cost.

[0023] The flame arrester of the present invention integrates the above pipeline overcurrent and overpressure protection device, combining the fire arresting function and the cutting function into one, saving equipment installation space at the pipeline site, reducing costs, and solving the needs of gas fire arresting and cutting at the same time.

[0024] The rectifier of the present invention integrates the above-mentioned pipeline overcurrent and overpressure protection device, combining the rectification function and the cut-off function into one, making the ultrasonic measurement on the pipeline more accurate. The built-in spherical seal has the function of rectification and noise reduction, and can also automatically cut off the airflow in the event of overcurrent and overpressure. The integration of multiple functions into one structure can be widely used in industrial gas pipeline sections, without the need to reserve a 5D to 10D straight pipe section on site, saving installation space and reducing construction costs. The use of this rectifier can achieve multiple functions such as noise reduction, rectification, and cut-off, so that the ultrasonic flowmeter on the pipeline not only measures accurately, but also achieves a safety protection function. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the internal structure of the flame arrester in the first embodiment of the present invention in a normal working state.

[0026] Figure 2 Schematic diagram of the internal structure of the flame arrester involved in the first embodiment of the present invention when the airflow is cut off.

[0027] Figure 3 Schematic diagram of the internal structure of the flame arrester involved in the first embodiment of the present invention during pressure relief operation.

[0028] Figure 4 Schematic diagram of the internal structure of the pressure relief valve in the flame arrester involved in Example 1 of the present invention.

[0029] Figure 5 Schematic diagram of the structure of the first flame arrester in the first embodiment of the present invention.

[0030] Figure 6 for Figure 5 Schematic diagram of the structure of the AA section.

[0031] Figure 7 This is a schematic diagram of the internal structure of the rectifier involved in the second embodiment of the present invention in a normal working state.

[0032] Figure 8 Schematic diagram of the internal structure of the rectifier involved in the second embodiment of the present invention when the airflow is cut off.

[0033] Figure 9 Schematic diagram of the internal structure of the rectifier involved in the second embodiment of the present invention during pressure relief operation.

[0034] Figure 10 This is a schematic structural diagram of an upstream noise reduction block in a rectifier involved in the second embodiment of the present invention.

[0035] The reference numerals in the figures are: 1. Shell; 11. Air inlet; 12. Air outlet; 13. First cavity; 14. Second cavity; 15. Partition; 16. First hole; 17. Second hole; 21. Seal; 22. First spring; 23. Guide rod; 3. Pressure relief valve; 31. Valve seat; 32. Pressure relief push rod; 33. Sealing gasket; 34. Second spring; 35. Exhaust hole; 351. Exhaust inlet; 352. Pilot hole; 353. Exhaust outlet; 36. Protective cap; 37. Screw; 38. Plug; 41. First flame arrester; 42. Second flame arrester; 51. Downstream noise reduction block; 52. Flow stabilizing tube bundle; 53. Upstream noise reduction block; 531. Noise reduction block filter; 532. Support rod. DETAILED DESCRIPTION

[0036] The exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0037] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. It should be noted that in the present disclosure, the terms "including", "configured with", and "set on" are used to express open-ended inclusion and mean that in addition to the listed elements / components / etc., there may be additional elements / components / etc.; the terms "first", "second", etc. are used only as labels and are not intended to limit the number or order of their objects; the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0038] Unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0039] Example 1 like Figures 1 to 6 As shown, in this embodiment, a flame arrester is disclosed, in which a pipeline overcurrent and overpressure protection device is integrated. Compared with traditional flame arresters, it not only has a fire-arresting function, but also can cut off the airflow in time when an overpressure situation occurs upstream of the pipeline or an overcurrent situation occurs in the pipeline and the downstream air pressure decreases, so as to maintain the pipeline in a safe state.

[0040] First, the pipeline overcurrent and overpressure protection device is described. The device includes a shell 1, a seal 21, a first spring 22 and a pressure relief valve 3. An air inlet 11 is provided at one end of the shell 1 for connecting to the upstream air supply pipeline, and an air outlet 12 is provided at the other end of the shell 1 for connecting to the downstream pipeline. A first cavity 13 and a second cavity 14 are formed inside the shell 1, and a first hole 16 and a second hole 17 are formed between the first cavity 13 and the second cavity 14. An annular partition 15 is provided in the shell 1 to divide the space inside the shell 1 into two parts, namely the first cavity 13 and the second cavity 14 mentioned above. The first hole 16 and the second hole 17 are provided on the partition 15, and the first cavity 13 and the second cavity 14 can be connected through both. The shell 1 is both the shell of the pipeline overcurrent and overpressure protection device and the shell of the flame arrester.

[0041] A seal 21 slides within the housing 1, one end of which is connected to a first spring 22. As the seal 21 slides, the first spring 22 expands and contracts. The seal 21 faces the first hole 16. When the seal 21 slides over the first hole 16, it blocks the hole 16, preventing gas from flowing between the first cavity 13 and the second cavity 14.

[0042] Specifically, in this embodiment, the sealing member 21 is slidably disposed within the first cavity 13 adjacent to the air inlet 11. The first spring 22 is a compression spring, the main body of which is disposed within the second cavity 14. The right end of the first spring 22 is fixed in the second cavity 14, and the left end of the first spring passes through the first hole 16 and is fixedly connected to the sealing member 21.

[0043] The pressure relief valve 3 is mounted on the side wall of the housing 1, with its inner end extending to the second hole 17, thereby controlling the opening and closing of the second hole 17. When the pressure relief valve 3 is open, the first cavity 13 and the second cavity 14 can communicate through the second hole 17; when the pressure relief valve 3 is closed, the second hole 17 is also closed.

[0044] During operation of the pipeline overcurrent and overpressure protection device in the flame arrester, when the difference between the upstream and downstream air pressures of the shell 1 is less than a preset value, the thrust of the airflow and the force of the first spring 22 on the seal 21 are equal or substantially equal, and the seal 21 maintains a certain distance from the first hole 16 to keep the gas transported downstream; when the upstream air pressure of the shell 1 is higher than the preset value of the downstream air pressure, the seal 21 is pushed by the airflow to overcome the force of the first spring 22 to seal on the first hole 16 and maintain the sealed state, cutting off the gas transport to the downstream.

[0045] When the upstream pressure of the housing 1 exceeds the preset downstream pressure, this corresponds to an overpressure condition in the pipeline upstream of the flame arrester, as well as an overflow condition in the pipeline, such as a rupture and loss of pressure downstream of the pipeline. In this case, the seal 21 can promptly block the first hole 16, preventing a safety accident. After the pipeline is repaired, the device will continue to maintain the state of cutting off the airflow, and the seal 21 will not automatically release the blockage of the first hole 16. At this time, the pressure relief valve 3 is gradually opened to connect the first cavity 13 and the second cavity 14, so that the air pressure upstream and downstream of the flame arrester is equal or substantially equal. The force applied to the seal 21 by the first spring 22 can push the seal 21 to the left, causing the seal 21 to release the blockage of the first hole 16, allowing the gas to flow smoothly and be transported downstream.

[0046] It should be noted that although the pipeline overcurrent and overpressure protection device relies on the specific structure of the housing 1 and the cooperation of the first spring 22 and the seal 21 to cut off the downstream gas flow in the event of overpressure and overcurrent, these technical features alone cannot restore the gas supply after the pipeline is repaired, that is, it cannot achieve the basic function of transmitting gas. Therefore, a pressure relief valve 3 is also provided in the pipeline overcurrent and overpressure protection device, which allows the user to adjust the air pressure difference between the upstream and downstream of the device after the pipeline is repaired, so that the seal 21 releases the blockage of the first hole 16 and ensures normal gas transmission. In other words, in the pipeline overcurrent and overpressure protection device, there is a close connection between the housing 1, the first spring 22, the seal 21, and the pressure relief valve 3. Through their synergistic effect, they jointly solve the technical problem of how to cut off and restore the airflow in the event of overcurrent and overpressure, and produce the related technical effect, namely, ensuring the safe transmission of gas in the pipeline. Removing any of these features cannot produce the above-mentioned technical effect of safely transmitting gas.

[0047] The pipeline overcurrent and overpressure protection device in the flame arrester utilizes a first spring 22 and a sliding seal 21 to cooperate within the housing 1. When gas flows within the device, the seal 21 is subjected to the thrust of the airflow and the force of the first spring 22, which are equal or substantially equal. The seal 21 maintains a certain distance from the first hole 16, maintaining the gas flow downstream. When the upstream air pressure of the housing 1 exceeds the preset downstream air pressure, the seal 21 is pushed by the airflow to overcome the force of the first spring 22 and seals against the first hole 16 and remains blocked, cutting off the gas flow downstream. Therefore, after the device is applied to a gas delivery pipeline, if an overpressure condition occurs upstream of the pipeline or an overflow condition occurs downstream, the seal 21 slides onto the first hole 16 to cut off the gas flow downstream, placing the pipeline in a safe state. Subsequent adjustment of the pressure relief valve 3 can make the air pressure upstream and downstream of the device equal or close to each other, and then the first spring 22 removes the seal 21 from the first hole 16, restoring gas flow. The pipeline overcurrent and overpressure protection device ensures that the pipeline in which it is located can safely transport gas. The pipeline overcurrent and overpressure protection device does not require a power supply during its entire operation. It also has a simple structure, is not prone to failure, has good stability, does not cause mis-tripping, and has a low manufacturing cost.

[0048] The flame arrester in this embodiment combines the fire arresting function and the cutting function into one. Specifically, the fire arresting function is realized by the first fire arresting net 41 and the second fire arresting net 42 provided in the housing 1. Figures 1 to 6 As shown, the first flame-blocking net 41 is fixed in the first cavity 13, and the second flame-blocking net 42 is fixed in the second cavity 14. The first flame-blocking net 41 and the second flame-blocking net 42 each include a plurality of continuously bent, annular steel sheets and a plurality of circular rings. The steel sheets and circular rings are spaced apart to form a disc-shaped structure, which can rely on its own structure to prevent or slow the spread of flames.

[0049] In this embodiment, a certain distance is set between the first fire-blocking net 41 and the second fire-blocking net 42, which can be used to set structures related to the cutting function and also increase the fire-blocking distance and improve the fire-blocking effect.

[0050] In this embodiment, the diameter of the middle portion of the flame arrester is larger than the diameters of the air inlet 11 and the air outlet 12. Figure 1 As shown, the central portion of the housing 1 is enlarged compared to the left and right ends, increasing the storage space for impurities after gas filtration. This also facilitates the installation of structures related to the cutoff function and can be integrated with the flame arrester. Compared to separate assembly, this reduces the overall installation size and enhances the flame-blocking effect, preventing the spread of fire.

[0051] In this embodiment, a guide rod 23 is fixedly provided in the housing 1, and the seal 21 is slidably mounted on the guide rod 23. The first spring 22 is sleeved on the guide rod 23 to ensure that the seal 21 slides smoothly within the housing 1. The ends of the guide rod 23 are respectively fixed to the first flame-blocking net 41 and the second flame-blocking net 42. This allows the guide rod 23 to be secured by utilizing the existing necessary structure without adding additional structural components to the housing 1.

[0052] The seal 21 is a spherical member mounted on a guide rod 23. During use, the seal 21 slides only along the length of the guide rod 23 and does not move in other directions, ensuring stable sealing of the first hole 16 under specified conditions. Furthermore, the spherical shape of the seal 21 facilitates gas flow within the pipeline and the flame arrester, and allows for smooth sealing of the first hole 16 even when there is a significant upstream and downstream pressure differential. The central positioning of the guide rod 23 and seal 21 in the middle of the housing 1 further increases gas flow velocity and the speed of sealing the first hole 16 even when there is a significant upstream and downstream pressure differential.

[0053] In some embodiments, the guide rod 23 may be directly fixed to the inner wall of the housing 1, and can also guide the sealing member 21 to slide within the housing 1. Alternatively, the sealing member 21 may be directly slidably connected to the inner wall of the housing 1, ensuring that the sealing member 21 can block the first hole 16 when sliding. For example, a plurality of sliding grooves may be provided on the inner wall of the housing 1, and the side surfaces of the sealing member 21 may be slidably assembled in these sliding grooves via connectors to enable the sealing member 21 to slide within the housing 1.

[0054] In some embodiments, the seal 21 may also be a non-spherical body, for example, it may be a cylinder, a barrel, an ellipsoid, a cuboid, etc., and one end close to the first hole 16 may have a plane or an arc surface opposite to the first hole 16, which can seal the first hole 16.

[0055] In some embodiments, the first spring 22 can also be provided in the first cavity 13 and configured as a tension spring. One end of the first spring 22 is connected to the end of the seal 21 away from the first hole 16, and the other end of the first spring 22 is fixed. When the seal 21 is pushed by the airflow, the first spring 22 is stretched, and the tension of the first spring 22 is equal to or substantially equal to the thrust of the airflow on the seal 21, thereby ensuring that a certain distance is maintained between the seal 21 and the first hole 16, and maintaining the circulation of the airflow; when the upstream air pressure exceeds the preset value of the downstream air pressure, the thrust applied by the airflow to the seal 21 increases significantly, and the seal 21 can be pressed tightly against the first hole 16 to cut off the airflow.

[0056] In the above embodiment, the first cavity 13 is located near the upstream air supply end, so the seal 21 is disposed within the first cavity 13 to achieve the aforementioned functions of shutting off the airflow. If the second cavity 14 is located near the upstream air supply end, the seal 21 can be disposed within the second cavity 14 to similarly achieve the aforementioned functions of shutting off the airflow.

[0057] In this embodiment, a structural form of the pressure relief valve 3 is disclosed. Please refer to Figures 1 to 4 The pressure relief valve 3 includes a valve seat 31, a pressure relief push rod 32, a sealing gasket 33, and a second spring 34. The valve seat 31 is mounted on the partition 15 and has an exhaust hole 35 formed therein that is connected to the second hole 17. The pressure relief push rod 32 is slidably arranged between the valve seat 31 and the side wall of the housing 1, with one end extending outside the housing 1 and capable of sliding along its own length under the action of external force. A sealing structure is provided between the pressure relief push rod 32 and the housing 1, as well as between the pressure relief push rod 32 and the valve seat 31, so that gas does not flow out from the gap between the pressure relief push rod 32 and the housing 1 and the valve seat 31. The exhaust hole 35 has a curved structure, and the sealing gasket 33 is mounted on the pressure relief push rod 32, with the side surface of the sealing gasket 33 facing the middle channel of the exhaust hole 35. The second spring 34 is arranged in the valve seat 31 and applies a force to the pressure relief push rod 32, causing the sealing gasket 33 to block the middle channel of the exhaust hole 35.

[0058] Specifically, the second spring 34 is a compression spring, one end of which rests against the inner end of the pressure relief push rod 32, exerting a force toward the outside of the housing 1. This forces the sealing gasket 33 to press against the central portion of the vent 35, thereby blocking the vent 35 and preventing communication between the first and second cavities 13, 14, and the vent 35 via the second hole 17. When pressure relief is required, the pressure relief push rod 32 is slid into the housing 1, overcoming the elastic force of the second spring 34. This allows the sealing gasket 33 to move away from the central portion of the vent 35, allowing gas to flow through the vent 35. The high-pressure gas in the first cavity 13 can then enter the second cavity 14 until the pressures in the two cavities are equal or nearly equal. The seal 21 then automatically opens under the force of the first spring 22, releasing the seal on the first hole 16. The provision of the pressure relief valve 3 avoids the dangerous situation of downstream end users activating gas use before the overpressure condition is resolved.

[0059] The pressure relief valve 3, seal 21, guide rod 23 and other structures are made of stainless steel or other high-temperature resistant materials. They can reliably cut off the airflow while having good fire resistance and wear resistance, no risk of air leakage, and higher safety performance.

[0060] In this embodiment, the exhaust hole 35 includes an exhaust inlet 351, an exhaust outlet 353, and a pilot hole 352. The exhaust inlet 351 is connected to the second hole 17, and the exhaust outlet 353 is connected to the downstream second cavity 14. The pilot hole 352 is located between the exhaust inlet 351 and the exhaust outlet 353, that is, in the middle of the exhaust hole 35. The pressure relief push rod 32, under the force of the second spring 34, drives the sealing gasket 33 to seal the pilot hole 352.

[0061] During pressure relief, after the pressure relief push rod 32 is pressed, the air flow first enters the pilot hole 352 through the exhaust inlet 351, and the pressure on the exhaust outlet 353 side increases, and the external force causes the sealing gasket 33 to drop simultaneously until the sealing gasket 33 is completely dropped. The air flow flows to the exhaust outlet 353 through the upper side of the sealing gasket 33, and the air pressure on both sides can reach the same level. The seal 21 is automatically opened by the thrust of the first spring 22, avoiding the dangerous situation that the downstream terminal user starts using gas before the overpressure state is relieved.

[0062] In this embodiment, the pressure relief valve 3 further includes a protective cap 36 mounted on the outer end of the pressure relief push rod 32, which can protect the pressure relief push rod 32 and prevent the outside from accidentally touching the pressure relief push rod 32 and affecting the cutting function of the device.

[0063] The flame arrester in this embodiment is based on the traditional flame arrester technology. By changing the internal structure and construction, a first spring 22, a seal 21 and other mechanisms are built in to realize the fire-arresting function and the gas-cutting function in the event of overcurrent and overpressure. When the pipeline gas pressure and flow rate fluctuate within a certain range, the gas can pass through the flame arrester smoothly by utilizing the force balance between the first spring 22 and the seal 21. When a break occurs in the downstream of the pipeline and pressure loss or other situations cause overcurrent, or when a failure of the upstream pressure regulating valve of the pipeline causes the pressure in the upstream pipeline to rise rapidly, the force balance between the first spring 22 and the seal 21 is broken, and the seal 21 can be quickly moved to the first hole 16 to cut off the flow of gas to the downstream. It solves the functions that can only be achieved by using four products: traditional flame arrester, pressure transmitter, emergency shut-off valve and controller. At the same time, it reduces the cost by about 90%, and does not require external power supply, thus avoiding the occurrence of accidental cut-off events.

[0064] This flame arrester can be used not only in industrial locations with large-diameter gas inlet pipes, but also before gas pipelines enter buildings in the catering and canteen industries. Combining a traditional flame arrester with a shut-off valve into one device saves space on-site for installing two devices. This solves the high cost and proneness to mis-operation of traditional flame arresters and shut-off valves, and can simultaneously meet the needs of gas flame arresting and shutting off. Example 2

[0065] like Figures 7 to 10As shown, in this embodiment, a rectifier is disclosed, in which a pipeline overcurrent and overpressure protection device is integrated. Compared with traditional rectifiers, it not only has a rectification function, but also can cut off the airflow in time when an overpressure situation occurs upstream of the pipeline or the air pressure decreases downstream of the pipeline due to an overcurrent situation, so as to maintain the pipeline in a safe state.

[0066] First, the pipeline overcurrent and overpressure protection device is described. The device includes a shell 1, a seal 21, a first spring 22 and a pressure relief valve 3. An air inlet 11 is provided at one end of the shell 1 for connecting to the upstream air supply pipeline, and an air outlet 12 is provided at the other end of the shell 1 for connecting to the downstream pipeline. A first cavity 13 and a second cavity 14 are formed inside the shell 1, and a first hole 16 and a second hole 17 are formed between the first cavity 13 and the second cavity 14. A cylindrical partition 15 is provided in the shell 1 to divide the space inside the shell 1 into two parts, namely the first cavity 13 and the second cavity 14 mentioned above. The first hole 16 is a port of the cylindrical partition 15, and the second hole 17 is provided on the partition 15, through which the first cavity 13 and the second cavity 14 can be connected. The shell 1 is both the outer shell of the pipeline overcurrent and overpressure protection device and the outer shell of the rectifier.

[0067] A seal 21 slides within the housing 1, one end of which is connected to a first spring 22. As the seal 21 slides, the first spring 22 expands and contracts. The seal 21 faces the first hole 16. When the seal 21 slides over the first hole 16, it blocks the hole 16, preventing gas from flowing between the first cavity 13 and the second cavity 14.

[0068] Specifically, in this embodiment, the seal 21 is slidably disposed in the first cavity 13 near the air inlet 11. The first spring 22 is a tension spring disposed in the first cavity 13, with its left end fixed in the first cavity 13 and its right end fixedly connected to the seal 21.

[0069] The pressure relief valve 3 is mounted on the side wall of the housing 1, with its inner end extending to the second hole 17, thereby controlling the opening and closing of the second hole 17. When the pressure relief valve 3 is open, the first cavity 13 and the second cavity 14 can communicate through the second hole 17; when the pressure relief valve 3 is closed, the second hole 17 is also closed.

[0070] During operation of the pipeline overcurrent and overpressure protection device in the rectifier, when the difference between the upstream and downstream air pressures of the shell 1 is less than a preset value, the thrust of the airflow and the force of the first spring 22 on the seal 21 are equal or substantially equal, and the seal 21 maintains a certain distance from the first hole 16 to keep the gas transported downstream; when the upstream air pressure of the shell 1 is higher than the preset value of the downstream air pressure, the seal 21 is pushed by the airflow to overcome the force of the first spring 22 to seal on the first hole 16 and maintain the sealed state, cutting off the gas transport to the downstream.

[0071] The upstream air pressure of the housing 1 is higher than the preset value of the downstream air pressure, which corresponds to an overpressure situation in the upstream pipeline of the rectifier, and corresponds to an overflow situation in the pipeline, such as a rupture and loss of pressure in the downstream of the pipeline. At this time, the seal 21 can timely block the first hole 16 to avoid safety accidents. After the pipeline is repaired, the device will continue to maintain the state of cutting off the airflow, and the seal 21 will not automatically release the blockage of the first hole 16. At this time, the pressure relief valve 3 is gradually opened to connect the first cavity 13 and the second cavity 14, so that the air pressure upstream and downstream of the rectifier is equal or substantially equal. The force applied to the seal 21 by the first spring 22 can pull the seal 21 to the left, so that the seal 21 releases the blockage of the first hole 16, and the gas can flow smoothly and be transported downstream.

[0072] It should be noted that although the pipeline overcurrent and overpressure protection device relies on the specific structure of the housing 1 and the cooperation of the first spring 22 and the seal 21 to cut off the downstream gas flow in the event of overpressure and overcurrent, these technical features alone cannot restore the gas supply after the pipeline is repaired, that is, it cannot achieve the basic function of transmitting gas. Therefore, a pressure relief valve 3 is also provided in the pipeline overcurrent and overpressure protection device, which allows the user to adjust the air pressure difference between the upstream and downstream of the device after the pipeline is repaired, so that the seal 21 releases the blockage of the first hole 16 and ensures normal gas transmission. In other words, in the pipeline overcurrent and overpressure protection device, there is a close connection between the housing 1, the first spring 22, the seal 21, and the pressure relief valve 3. Through their synergistic effect, they jointly solve the technical problem of how to cut off and restore the airflow in the event of overcurrent and overpressure, and produce the related technical effect, namely, ensuring the safe transmission of gas in the pipeline. Removing any of these features cannot produce the above-mentioned technical effect of safely transmitting gas.

[0073] The pipeline overcurrent and overpressure protection device in the rectifier utilizes a first spring 22 and a sliding seal 21 within the housing 1. When gas flows within the device, the thrust of the airflow and the force of the first spring 22 on the seal 21 are equal or substantially equal, maintaining a certain distance between the seal 21 and the first hole 16, thereby preventing gas from flowing downstream. When the upstream pressure of the housing 1 exceeds a preset value for the downstream pressure, the seal 21, pushed by the airflow, overcomes the force of the first spring 22 and seals against the first hole 16, maintaining the blockage and cutting off the flow of gas downstream. Therefore, when the device is applied to a gas pipeline, if an overpressure condition occurs upstream of the pipeline or an overflow condition occurs downstream, the seal 21 slides onto the first hole 16, cutting off the flow of gas downstream and placing the pipeline in a safe state. Subsequent adjustment of the pressure relief valve 3 can equalize or approximate the pressures upstream and downstream of the device, and the first spring 22 then removes the seal 21 from the first hole 16, restoring gas flow. The pipeline overcurrent and overpressure protection device ensures that the pipeline in which it is located can safely transport gas. The pipeline overcurrent and overpressure protection device does not require a power supply during its entire operation. It also has a simple structure, is not prone to failure, has good stability, does not cause mis-tripping, and has a low manufacturing cost.

[0074] The rectifier in this embodiment combines the rectifying function and the cutting function into one. Specifically, the rectifying function can be realized by the downstream noise reduction block 51 and the flow stabilizing tube bundle 52 arranged in the housing 1. Figures 7 to 10 As shown, the downstream noise reduction block 51 is fixedly installed in the second cavity 14 at the downstream. It has a mesh structure. The flow stabilizing tube bundle 52 is located downstream of the downstream noise reduction block 51 and is composed of a plurality of tubes filled in the second cavity 14 and arranged along the length of the second cavity 14.

[0075] The mesh-like structure of the downstream noise reduction block 51 divides the airflow, initially rectifying it and evens out its velocity. The friction and collision between the airflow and the mesh in the downstream noise reduction block 51 dissipate some of its kinetic energy, thereby reducing the noise intensity of the airflow. Furthermore, the metal mesh structure in the downstream noise reduction block 51 rapidly absorbs the heat of the flame during a pipe flashback, lowering the temperature in the combustion area below the ignition point of the combustible gas. This prevents the flame from propagating further through the mesh and also acts as a fire barrier.

[0076] The airflow passing through the downstream noise reduction block 51 enters the flow stabilizing tube bundle 52 and is further sorted. The airflow velocity on the outlet side will be more uniform and the direction will be consistent, which is convenient for the subsequent accurate measurement by the ultrasonic flow meter.

[0077] In this embodiment, a partition cavity is provided between the downstream noise reduction block 51 and the flow stabilizing tube bundle 52, which can increase the fire-blocking distance and improve the fire-blocking effect. It is also beneficial for the downstream noise reduction block 51 and the flow stabilizing tube bundle 52 to cooperate in rectification, and has a better rectification effect than directly connecting the two.

[0078] In this embodiment, an upstream noise reduction block 53 is fixedly installed in the first cavity 13. A noise reduction block filter 531 is provided in the middle of the upstream noise reduction block 53, which is opposite to the air inlet 11. Specifically, the noise reduction block filter 531 is fixedly connected to the inner wall of the first cavity 13 through a plurality of support rods 532 on the periphery. Figure 9 and Figure 10 As shown, one end of the support rod 532 is fixedly connected to the noise reduction block filter 531, and the other end is fixedly connected to the inner wall of the first cavity 13. The noise reduction block filter 531 and the support rod 532 are made of metal. When the airflow enters the shell 1 from the front air inlet 11, the upstream noise reduction block 53 can divide the airflow, initially rectify the airflow, and make the airflow speed tend to be uniform. The friction and collision between the airflow and the mesh will consume part of the kinetic energy, thereby reducing the noise intensity of the airflow. The metal mesh quickly absorbs the heat of the flame, making the temperature of the combustion area lower than the ignition point of the combustible gas, resulting in the flame being unable to continue to propagate through the mesh, and has a certain fire-blocking function.

[0079] The rectifier in this embodiment mainly rectifies the chaotic airflow upstream and reduces the noise generated by the bends and reductions. It also has built-in pressure-sensitive elements (i.e., the first spring 22 and the seal 21). When the pressure at the front and rear ends is unbalanced, the pipeline can be cut off to prevent the gas from continuing to flow, thereby avoiding the occurrence of fire and achieving safe gas transportation.

[0080] In this embodiment, a guide rod 23 is fixedly provided in the housing 1, and the seal 21 is slidably mounted on the guide rod 23. The first spring 22 is sleeved on the guide rod 23 to ensure that the seal 21 slides smoothly within the housing 1. One end of the guide rod 23 is fixed to the upstream noise reduction block 53, and the guide rod 23 can be secured by utilizing the existing necessary structure without adding additional structural components to the housing 1.

[0081] The seal 21 is a spherical member mounted on a guide rod 23. During actual use, the seal 21 can only slide along the length of the guide rod 23 and does not move in other directions, ensuring stable sealing of the first hole 16 under specified conditions. Furthermore, the spherical shape of the seal 21 further facilitates gas flow within the pipeline and the rectifier, providing a certain degree of rectification and enabling smooth sealing of the first hole 16 even when there is a significant upstream and downstream pressure differential. The guide rod 23 and seal 21 are centrally located in the middle of the housing 1, further increasing the gas flow rate and the speed of sealing the first hole 16 when there is a significant upstream and downstream pressure differential.

[0082] In the normal ventilation state, after the airflow passes through the front noise reduction block for initial noise reduction and rectification, it enters the buffer zone on the left side of the seal 21. The airflow eliminates turbulence and velocity gradient here, and the airflow velocity distribution is more uniform, the pressure is balanced and the fluctuation is attenuated, which alleviates the pressure drop caused by the front noise reduction block and avoids negative pressure or pressure oscillation in the downstream. The large space and low flow rate characteristics of the buffer zone extending to the right of the seal 21 can also slow down the flame propagation speed and reduce the risk of explosion. The seal 21 blocks the airflow in the buffer zone formed by the first cavity 13, forming multiple airflow vortices, further reducing the velocity gradient of the airflow, weakening the turbulence intensity, and making the airflow relatively smooth.

[0083] In some embodiments, the guide rod 23 may be directly fixed to the inner wall of the housing 1, and can also guide the sealing member 21 to slide within the housing 1. Alternatively, the sealing member 21 may be directly slidably connected to the inner wall of the housing 1, ensuring that the sealing member 21 can block the first hole 16 when sliding. For example, a plurality of sliding grooves may be provided on the inner wall of the housing 1, and the side surfaces of the sealing member 21 may be slidably assembled in these sliding grooves via connectors to enable the sealing member 21 to slide within the housing 1.

[0084] In some embodiments, the seal 21 may also be a non-spherical body, for example, it may be a cylinder, a barrel, an ellipsoid, a cuboid, etc., and one end close to the first hole 16 may have a plane or an arc surface opposite to the first hole 16, which can seal the first hole 16.

[0085] In some embodiments, when the space of the second cavity 14 is relatively large, the main part of the first spring 22 can also be arranged in the second cavity 14 and set as a compression spring, that is, a structure similar to that in Example 1. One end of the first spring 22 is connected to the end of the seal 21 close to the first hole 16, and the other end of the first spring 22 is fixed. When the seal 21 is pushed by the airflow, the first spring 22 is compressed, and the elastic force of the first spring 22 is equal to or substantially equal to the thrust of the airflow on the seal 21, which can ensure that a certain distance is maintained between the seal 21 and the first hole 16 to maintain the circulation of the airflow; when the upstream air pressure exceeds the preset value of the downstream air pressure, the thrust applied by the airflow to the seal 21 increases significantly, which can press the seal 21 tightly against the first hole 16 to cut off the airflow.

[0086] In the above embodiment, the first cavity 13 is located near the upstream air supply end, so the seal 21 is disposed within the first cavity 13 to achieve the aforementioned functions of shutting off the airflow. If the second cavity 14 is located near the upstream air supply end, the seal 21 can be disposed within the second cavity 14 to similarly achieve the aforementioned functions of shutting off the airflow.

[0087] In this embodiment, another structural form of the pressure relief valve 3 is disclosed. Please refer to Figures 7 to 9The pressure relief valve 3 includes a screw rod 37 and a plug 38. The screw rod 37 is threadedly connected to the side wall of the housing 1, and its outer end extends outside the housing 1, allowing the user to operate and rotate it; the plug 38 is fixed to the inner end of the screw rod 37 and is opposite to the second hole 17.

[0088] When the screw rod 37 rotates and moves toward the inside of the housing 1, the plug 38 blocks the second hole 17, preventing the first cavity 13 and the second cavity 14 from communicating with the exhaust hole 35 via the second hole 17. When the screw rod 37 rotates and moves out of the housing 1, the plug 38 releases the blockage of the second hole 17, allowing the high-pressure gas in the first cavity 13 to enter the second cavity 14 until the pressures in the two cavities are equal or nearly equal. The seal 21 then automatically opens under the force of the first spring 22, releasing the blockage of the first hole 16. By providing the pressure relief valve 3, the dangerous situation of downstream end users starting to use gas before the overpressure condition is relieved is avoided.

[0089] The pressure relief valve 3, seal 21, guide rod 23 and other structures are made of stainless steel or other high-temperature resistant materials. They can reliably cut off the airflow while having good fire resistance and wear resistance, no risk of air leakage, and higher safety performance.

[0090] In this embodiment, the pressure relief valve 3 further includes a protective cap 36 sleeved on the outer end of the screw rod 37, which can protect the screw rod 37 and prevent the outside from accidentally touching the screw rod 37 and affecting the cutting function of the device.

[0091] The rectifier in this embodiment has the function of rectifying and reducing the noise of the airflow, making the ultrasonic measurement downstream of the pipeline more accurate. At the same time, the built-in spherical seal 21 has the function of rectifying and reducing noise, and can also automatically cut off the airflow when there is overcurrent and overpressure. Integrating multiple functions into one structure can be widely used in industrial gas pipeline sections, without reserving 5D to 10D straight pipe sections on site, saving installation space. Integrating multiple functions into one, reducing the cost, using one device to achieve multiple functions of noise reduction, rectification, and cutting, so that the ultrasonic flowmeter downstream of the pipeline not only measures accurately, but also can achieve the function of safely transporting gas.

[0092] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A pipeline overcurrent and overpressure protection device, characterized in that: include: The housing has an air inlet at one end and an air outlet at the other end, a first cavity and a second cavity formed therein, and a first hole and a second hole formed between the first cavity and the second cavity; a sealing member, slidably disposed in the housing, one end of which is connected to the first spring; a pressure relief valve, provided on the side wall of the housing, with an inner end extending to the second hole, for controlling the opening and closing of the second hole; in When the difference between the upstream air pressure and the downstream air pressure of the shell is less than a preset value, the thrust of the airflow and the force of the first spring on the seal are equal or basically equal, and the seal maintains a certain distance from the first hole to keep the gas transported downstream; when the upstream air pressure of the shell is higher than the preset value of the downstream air pressure, the seal is pushed by the airflow to overcome the force of the first spring to seal on the first hole and maintain the sealing state, cutting off the gas transport to the downstream.

2. The pipeline overcurrent and overpressure protection device according to claim 1, characterized in that: A guide rod is fixedly provided in the shell, and the sealing member is slidably provided on the guide rod.

3. The pipeline overcurrent and overpressure protection device according to claim 2, characterized in that: The sealing member is a sphere sleeved on the guide rod.

4. The pipeline overcurrent and overpressure protection device according to claim 2, characterized in that: The first spring is a compression spring provided downstream of the sealing member and sleeved on the guide rod, with one end of the first spring away from the sealing member being fixed on the guide rod; or The first spring is a tension spring arranged upstream of the sealing member and sleeved on the guide rod, and one end of the first spring away from the sealing member is fixed on the guide rod.

5. The pipeline overcurrent and overpressure protection device according to claim 1, characterized in that: The pressure relief valve comprises: a valve seat having a vent hole formed therein and communicating with the second hole; a pressure relief push rod, slidably disposed between the valve seat and the side wall of the housing; A sealing gasket, sleeved on the pressure relief push rod; The second spring is provided in the valve seat and applies a force to the pressure relief push rod to make the sealing gasket block the exhaust hole; wherein, When the pressure relief push rod slides into the housing, the sealing gasket releases the blockage of the exhaust hole.

6. The pipeline overcurrent and overpressure protection device according to claim 5, characterized in that: The exhaust hole includes an exhaust inlet, an exhaust outlet, and a pilot hole, wherein the exhaust inlet is connected to the second hole, the exhaust outlet is connected to the second cavity close to the downstream, and the pilot hole is arranged between the exhaust inlet and the exhaust outlet; The pressure relief push rod is acted upon by the second spring and drives the sealing gasket to seal against the pilot hole.

7. The pipeline overcurrent and overpressure protection device according to claim 1, characterized in that: The pressure relief valve comprises: a screw rod, threadedly connected to the side wall of the housing; A plug is fixedly arranged at the inner end of the screw rod, opposite to the second hole; When the screw rod rotates and moves toward the inside of the housing, the plug blocks the second hole; when the screw rod rotates and moves out of the housing, the plug releases the blockage of the second hole.

8. A flame arrester, characterized in that: include: The pipeline overcurrent and overpressure protection device according to any one of claims 1 to 7; a first fire-blocking net, fixed in the first cavity; The second fire-blocking net is fixed in the second cavity.

9. The flame arrester according to claim 8, characterized in that When a guide rod is provided in the shell, both ends of the guide rod are fixed on the first fire-blocking net and the second fire-blocking net respectively.

10. The flame arrester according to claim 8, characterized in that The diameter of the middle portion of the flame arrester is larger than the diameters of the air inlet and the air outlet.

11. A rectifier, characterized in that: include: The pipeline overcurrent and overpressure protection device according to any one of claims 1 to 7; A downstream noise reduction block is fixedly arranged in the second cavity located downstream and has a mesh structure; The flow stabilizing tube bundle is arranged downstream of the downstream noise reduction block and is a plurality of tubes filled in the second cavity. The tubes are arranged along the length direction of the second cavity.

12. The rectifier according to claim 11, wherein Also includes: The upstream noise reduction block is fixedly arranged in the first cavity located upstream, and a noise reduction block filter is provided in the middle thereof opposite to the air inlet.

13. The rectifier according to claim 12, wherein: When a guide rod is provided in the shell, one end of the guide rod is fixed on the upstream noise reduction block.

14. The rectifier according to claim 12, wherein: The upstream noise reduction block further includes a support rod, one end of which is connected to the noise reduction block filter screen, and the other end of which is connected to the inner wall of the first cavity.

Images