LNG (Liquefied Natural Gas) pipeline connecting device and conveying system
By using a self-diagnostic and self-repairing device with deformation gaskets and pressure sensing units at the flange connection of LNG pipelines, the problem of insufficient sealing of traditional LNG pipelines has been solved, achieving efficient leak detection and automatic repair, and reducing operation and maintenance costs and risks.
Patent Information
- Application Number
- CN202520879823.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-07
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-05-07
AI Technical Summary
Traditional LNG pipeline flange connections are prone to sealing failure under low temperature, pressure fluctuation, or vibration conditions. Existing leak detection response is lagging and maintenance costs are high, especially in coastal or earthquake-prone areas where the risk increases.
The LNG pipeline connection device uses a deformation gasket and a pressure sensing unit. The deformation gasket automatically contracts to increase the bolt preload when there is a leak, and the pressure sensing unit monitors in real time and provides remote alarms, realizing self-diagnosis and self-repair.
It improves sealing reliability, reduces the frequency of manual inspections and maintenance costs, and reduces unplanned downtime losses. It is suitable for LNG facilities affected by earthquakes or drastic temperature changes.
Smart Images
Figure CN223953538U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to pipeline connection technical field especially a kind of LNG pipeline connecting device and conveying system. BACKGROUND
[0002] LNG (Liquefied Natural Gas, liquefied natural gas) pipeline as the core facility of liquefied natural gas transportation, the sealing of its flange connection is directly related to system safety.
[0003] Traditional flange joint uses ordinary metal gasket and bolt fixation, but under long-term low temperature, pressure fluctuation or vibration working condition, it is easy to cause sealing failure due to the difference of material thermal expansion and cold shrinkage, and cause natural gas leakage.
[0004] In prior art, leakage detection is mostly dependent on artificial inspection or external sensor, and there are problems such as response lag and positioning difficulty; and emergency treatment after leakage usually needs to stop and re-tighten bolt, resulting in high operation and maintenance cost and safety hazard. Especially for LNG receiving station in coastal or earthquake-prone area, due to factors such as drastic change of ambient temperature and foundation settlement, the leakage risk of pipeline flange is significantly increased.
[0005] Therefore, it is urgent to provide a LNG pipeline connecting device and conveying system to solve the above technical problems. CONTENT OF UTILITY MODEL
[0006] The utility model aims at providing a LNG pipeline connecting device and conveying system, with self-diagnosis and self-repair functions, to improve sealing reliability and operation and maintenance efficiency. The preferred technical solutions in many technical solutions provided by the utility model can produce many technical effects, which are described in detail below.
[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions:
[0008] The utility model provides a LNG pipeline connecting device, comprising:
[0009] Flange assembly, comprising first flange, second flange and sealing structure arranged between the first flange and the second flange;
[0010] Bolt assembly, comprising screw rod and nut sleeved on the screw rod, the bolt assembly is used for connecting the first flange and the second flange;
[0011] Deformation gasket, arranged between the nut and the first flange;
[0012] Pressure sensing unit, arranged on the first flange and / or the second flange, for signal connection with control terminal.
[0013] Preferably, the end face of the first flange plate and / or the second flange plate is provided with an annular sealing groove, and the sealing structure is arranged in the sealing groove.
[0014] Preferably, the shape change gasket comprises a memory alloy gasket, and the shape change trigger temperature of the memory alloy gasket is -50 DEG C.
[0015] Preferably, the alloy comprises a nickel-titanium alloy.
[0016] Preferably, the bolt assembly further comprises a warning light, and the warning light is signal connected to the control terminal.
[0017] Preferably, the bolt comprises an alloy bolt, and the warning light is arranged at the end of the bolt.
[0018] Preferably, the pressure sensing unit comprises 3-6 micro pressure sensors which are uniformly distributed in the circumferential direction on the end face of the first flange plate and / or the second flange plate.
[0019] Preferably, the pressure sensor is embedded in the side wall of the sealing groove and is in the same plane as the sealing structure.
[0020] An LNG conveying system comprises a pipeline and the LNG pipeline connecting device.
[0021] The LNG pipeline connecting device and the conveying system provided by the utility model realize "mechanical compensation + intelligent early warning" double protection, reduce the artificial inspection frequency, avoid the non-planned shutdown loss, and reduce the comprehensive operation and maintenance cost. BRIEF DESCRIPTION OF DRAWINGS
[0022] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.
[0023] Figure 1 It is the structure schematic view of one embodiment of the LNG pipeline connecting device of the utility model;
[0024] Figure 2It is the working principle diagram of the LNG pipeline connecting device.
[0025] In the figure: 1, flange assembly; 11, first flange; 12, second flange; 100, sealing groove;
[0026] 2, bolt assembly; 21, screw rod; 22, nut; 23, warning light;
[0027] 3, deformation gasket;
[0028] 4, pressure sensing unit;
[0029] 5, control terminal. DETAILED DESCRIPTION
[0030] In order to make the purpose, technical scheme and advantages of the utility model more clear, the technical scheme of the utility model will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the scope protected by the utility model.
[0031] Figure 1 It is the structural schematic diagram of the embodiment, as shown in Figure 1 The utility model provides a kind of LNG pipeline connecting device, including flange assembly 1, bolt assembly 2, deformation gasket 3 and pressure sensing unit 4.
[0032] Wherein, flange assembly 1 includes first flange 11, second flange 12 and the sealing structure (not shown in the figure) being arranged between first flange 11 and second flange 12;The pair of flanges of the embodiment, i.e. first flange 11 and second flange 12 are made of low-temperature stainless steel material, and the sealing structure is made of low-temperature resistant rubber sealing ring for preliminary sealing pipeline interface.
[0033] Specifically, annular sealing groove 100 is arranged on the end face of first flange 11 and / or second flange 12 in the embodiment, and sealing structure is arranged in sealing groove 100, so as to effectively limit sealing structure by sealing groove 100, to ensure the stability of sealing structure.
[0034] It can be understood that the end face here is the end of first flange 11 and second flange 12 close to each other. In actual production and use process, annular sealing groove 100 can be arranged on first flange 11, also can be arranged on second flange 12, also can be arranged groove structure on the end face of first flange 11 and second flange 12, and two groove structures on first flange 11 and second flange 12 are combined to form annular sealing groove 100.
[0035] like Figure 1 As shown, in this embodiment, the bolt assembly 2 is used to connect the first flange 11 and the second flange 12. The bolt assembly 2 includes a screw 21 and a nut 22 sleeved on the screw 21. The bolt assembly 2 uses a high-strength alloy bolt and is equipped with a lock nut 22.
[0036] A deformation washer 3 is disposed between the nut 22 and the first flange 11. In this embodiment, the deformation washer 3 is a shape memory alloy washer, preferably a nickel-titanium alloy, with a deformation trigger temperature of -50°C, which matches the local low temperature caused by LNG leakage. When the flange assembly 1 experiences low temperature due to leakage, the deformation washer 3 can contract to generate additional preload, increasing the preload of the bolt assembly 2 by 20%-30%. By actively sealing and compensating for bolt loosening through the deformation washer 3, the leakage diffusion can be significantly delayed, buying time for emergency repairs.
[0037] Figure 2 This is a schematic diagram illustrating the working principle of this embodiment, as follows: Figure 2 As shown, this embodiment also includes a pressure sensing unit 4 for real-time monitoring of the pressure distribution on the sealing surface. The pressure sensing unit 4 is mounted on the first flange 11 and / or the second flange 12, and is used to connect to the control terminal 5 via signal transmission, enabling data to be wirelessly transmitted to the control terminal 5.
[0038] Specifically, in this embodiment, the pressure sensing unit 4 includes 3-6 miniature pressure sensors evenly distributed circumferentially on the end faces of the first flange 11 and / or the second flange 12. The pressure sensing unit 4 can quickly identify areas of abnormal pressure on the sealing surface with a positioning accuracy of ±5cm, which can accurately locate leaks compared to traditional methods, improving efficiency by 70%.
[0039] Optionally, the pressure sensor is embedded in the side wall of the sealing groove 100 and is in the same plane as the sealing structure. This arrangement ensures the detection accuracy of the pressure sensing unit 4.
[0040] As an optional implementation, the bolt assembly 2 also includes a warning light 23, such as Figure 2 As shown, the warning light 23 is connected to the control terminal 5. In this embodiment, the warning light 23 is an LED light, which is located on the end of the screw 21 away from the nut 21.
[0041] Optionally, the bolt assembly 2 in this embodiment integrates a signal processing circuit. When the pressure sensor detects that the pressure drop exceeds a threshold (e.g., 15%), it triggers the LED to flash red; at the same time, mechanical self-locking is achieved through the contraction of the deformation washer 3.
[0042] The LNG pipeline connecting device, the flange plate assembly 1 is provided with a sealing structure and is connected through the bolt assembly 2, the deformation gasket 3 is pre-tightened between the nut 22 and the flange plate, the pressure sensing unit 4 is embedded in the flange plate, when the flange sealing fails to cause LNG leakage, the temperature near the leakage point is suddenly reduced to trigger the deformation gasket 3 to shrink, and the bolt pre-tightening force is automatically increased; at the same time, the pressure sensing unit 4 monitors the sealing surface pressure change in real time, and remotely alarms to synchronously prompt the leakage position, realizes the double protection of ''mechanical compensation + intelligent early warning'', reduces the artificial inspection frequency by more than 50%, avoids the loss of unplanned shutdown, and reduces the comprehensive operation and maintenance cost by 40%.
[0043] The LNG pipeline connecting device is mainly suitable for the flange connecting parts of LNG receiving stations, liquefied natural gas conveying pipelines and tank areas, and is particularly suitable for the following scenes.
[0044] 1. Pipeline anti-seismic reinforcement in earthquake zones or geologically unstable areas;
[0045] 2. Coastal LNG facilities frequently experiencing sudden temperature changes;
[0046] 3. Core process pipelines (such as BOG recovery pipelines) with extremely low leakage tolerance.
[0047] The embodiment also provides an LNG conveying system comprising a pipeline and the LNG pipeline connecting device described above, and the LNG pipeline connecting device is used for connecting the pipeline. The LNG conveying system is provided with the LNG pipeline connecting device, the flange plate assembly 1 is provided with a sealing structure and is connected through the bolt assembly 2, the deformation gasket 3 is pre-tightened between the nut 22 and the flange plate, the pressure sensing unit 4 is embedded in the flange plate, when the flange sealing fails to cause LNG leakage, the temperature near the leakage point is suddenly reduced to trigger the deformation gasket 3 to shrink, and the bolt pre-tightening force is automatically increased; at the same time, the pressure sensing unit 4 monitors the sealing surface pressure change in real time, and remotely alarms to synchronously prompt the leakage position, realizes the double protection of ''mechanical compensation + intelligent early warning'', reduces the artificial inspection frequency by more than 50%, avoids the loss of unplanned shutdown, and reduces the comprehensive operation and maintenance cost by 40%.
[0048] The above is only a specific implementation manner of the utility model, but the protection scope of the utility model is not limited to this, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the utility model, which should be covered in the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.
Claims
1. An LNG pipeline connection device, characterized in that, include: A flange assembly includes a first flange, a second flange, and a sealing structure disposed between the first flange and the second flange; A bolt assembly, including a threaded rod and a nut fitted on the threaded rod, the bolt assembly being used to connect a first flange and a second flange; A deformation washer is disposed between the nut and the first flange; A pressure sensing unit is disposed on the first flange and / or the second flange for signal connection with the control terminal.
2. The LNG pipeline connection device according to claim 1, characterized in that: An annular sealing groove is provided on the end face of the first flange and / or the second flange, and the sealing structure is provided in the sealing groove.
3. An LNG pipeline connection device according to claim 1 or 2, characterized in that: The deformation gasket includes a shape memory alloy gasket with a deformation trigger temperature of -50°C.
4. An LNG pipeline connection device according to claim 3, characterized in that: The alloy includes a nickel-titanium alloy.
5. An LNG pipeline connection device according to claim 1 or 2, characterized in that: The bolt assembly also includes a warning light, which is signal-connected to the control terminal.
6. An LNG pipeline connection device according to claim 5, characterized in that: The bolts are alloy bolts, and the warning light is located at the end of the screw.
7. An LNG pipeline connection device according to claim 2, characterized in that: The pressure sensing unit includes 3-6 miniature pressure sensors evenly distributed circumferentially on the end face of the first flange and / or the second flange.
8. An LNG pipeline connection device according to claim 7, characterized in that: The pressure sensor is embedded in the side wall of the sealing groove and is in the same plane as the sealing structure.
9. An LNG transportation system, characterized in that, It includes a pipeline and an LNG pipeline connection device as described in any one of claims 1-8, the LNG pipeline connection device being used to connect the pipeline.