A novel LNG ship cavitation vent pipe penetration component
By adopting a novel cavitation vent pipe structure with expansion joints and outer protective sleeves on LNG ships, the problem of cavitation vent pipe leakage has been solved, achieving improvements in safety and economy, ensuring ship safety and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA MERCHANTS HEAVY IND JIANGSU
- Filing Date
- 2025-07-03
- Publication Date
- 2026-06-30
Smart Images
Figure CN224427781U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of construction technology, and in particular to a novel LNG ship cavitation vent pipe penetration component. Background Technology
[0002] Due to the structural limitations of LNG carriers' cargo holds, cavitation often occurs during navigation, where natural gas accumulates, reducing cargo loading capacity and navigation safety. To improve loading capacity, cavitation is typically connected to the liquid dome via a vent pipe, thus concentrating all gas in the hold at the liquid dome. This vent pipe must pass through the headspace to the open deck and then extend to the liquid dome. Because this vent pipe is a single-walled pipe and directly connected to the cargo hold, a leak in this pipe during ship operation can cause natural gas or LNG to leak into the headspace, affecting ship operation and navigation safety. Shipyards both domestically and internationally often mitigate this risk by installing additional compartments, but these systems are costly and cannot guarantee strict pipeline safety.
[0003] Patent application CN 113007452A discloses a watertight flexible passage device for an LNG dual-fuel pipeline. An opening for the LNG dual-fuel pipeline to pass through is provided in the bulkhead of the watertight / airtight compartment. The opening is within the inner circle of an expansion joint flange. A bulkhead connecting plate is provided on the bulkhead of the watertight / airtight compartment around the opening. An expansion joint is fitted onto the LNG dual-fuel pipeline near the watertight / airtight compartment. The expansion joint includes an expansion joint body and expansion joint flanges located at both ends of the expansion joint body. The expansion joint connecting flange near the watertight / airtight compartment is connected to the bulkhead connecting plate. A pipeline connecting plate is provided on the LNG dual-fuel pipeline outside the expansion joint connecting flange at the end away from the watertight / airtight compartment, and the expansion joint connecting flange at this end is connected to the pipeline connecting plate.
[0004] The existing device is not a detachable structure, and the safety of the cutting device needs to be improved.
[0005] Therefore, a new technical solution is needed to solve the above-mentioned technical problems. Utility Model Content
[0006] The purpose of this utility model is to provide a new type of LNG ship cavitation vent pipe penetration component, which can effectively eliminate the risk of pipeline leakage into the headspace, has strong feasibility, and improves the safety of the ship.
[0007] The technical solution adopted in this utility model is:
[0008] A novel LNG carrier cavitation vent pipe penetration component includes a top deck, an expansion joint, and an outer protective sleeve. The expansion joint and the outer protective sleeve are arranged sequentially. The cavitation vent pipe extends through the expansion joint and the outer protective sleeve to below the top deck. The expansion joint is fixed to the top deck by a flange and is located above the top deck. The outer protective sleeve is fixed to the top deck by a flange and is located below the top deck. The outer protective sleeve includes an upper outer protective sleeve and a lower outer protective sleeve.
[0009] By adopting the above structure, the device can ensure the normal ventilation function of the cavitation vent pipe on the ship. In the event of an accidental leak of LNG or natural gas in the pipeline, the external protective sleeve can effectively prevent it from leaking into the headspace and causing danger.
[0010] Preferably, the cavitation vent pipe includes an upper cavitation vent pipe and a lower cavitation vent pipe, and the upper cavitation vent pipe and the lower cavitation vent pipe are connected by a connecting flange at the top of the lower cavitation vent pipe, and the connecting flange is a threaded flange.
[0011] Preferably, the upper vent pipe extends into the expansion joint and is fixed to the expansion joint via inner and outer flanges.
[0012] Preferably, the top deck is provided with a lower welded component, and the expansion joint is fixedly connected to the lower welded component.
[0013] Preferably, an upper welded component is provided under the top deck, and the outer protective sleeve is fixedly connected to the upper welded component.
[0014] By adopting the above structure and setting expansion joints, it is possible to prevent stress concentration caused by the deformation of the cavitation vent pipe and its inconsistency with the top deck, which could lead to pipe damage.
[0015] Preferably, the outer protective sleeve includes an upper outer protective sleeve and a lower outer protective sleeve, which are fixed together by a flange connection to form a headspace compartment. The lower cavitation vent pipe is sealed inside the headspace compartment, and polyurethane insulation is installed on the outside to form protection and prevent LNG or natural gas from leaking into the headspace compartment due to damage.
[0016] Preferably, the lower part of the lower cavitation vent pipe passes through the welding plate connected to the bottom of the topspace chamber. At the intersection of the lower cavitation vent pipe and the welding plate, there is a welding elbow plate. Below the welding plate is a connecting sleeve. The inner wall of the sleeve and the lower cavitation vent pipe are filled with glass insulating cotton.
[0017] Preferably, the outer wall of the upper outer protective sleeve is provided with a purge port and a gas detector, and the outer wall of the lower outer protective sleeve is provided with a purge port.
[0018] By adopting the above structure, a purge port can be set up to connect a nitrogen pipe to purge the inside after a leak, and the gas detector can detect in real time whether there is a dangerous gas leak inside the pipe.
[0019] Compared with the prior art, this utility model has the following advantages:
[0020] 1. This utility model device can reduce shipyard costs and ship weight. Compared with the commonly used compartmentalized devices, this device starts from the design source and uses a protective sleeve with a purging function. It is smaller in size and can effectively reduce shipyard costs and empty ship weight.
[0021] 2. This utility model device effectively ensures the safety of ship operation. The through-tank component involved in this device effectively eliminates the risk of natural gas and LNG leaking into the headspace, thus ensuring the safety of ship operation.
[0022] 3. When this utility model device is used, it can ensure the normal ventilation function of the cavitation vent pipe on the ship. When the pipeline accidentally leaks LNG or natural gas, the external protective sleeve can effectively prevent it from leaking into the headspace and causing danger. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the structure of this utility model;
[0024] Figure 2 This utility model Figure 1 A sectional view of aa;
[0025] Figure 3 This is a schematic diagram showing the position and structure of the expansion joint of this utility model;
[0026] Figure 4 This is a schematic diagram of the position and structure of the outer protective sleeve of this utility model.
[0027] The components include: 1. Upper cavitation vent pipe; 2. Expansion joint; 3. Upper welded component; 4. Lower welded component; 5. Upper outer protective sleeve; 6. Lower outer protective sleeve; 7. Glass insulation wool; 8. Polyurethane insulation; 9. Welded elbow plate; 10. Top plate; 11. Purge port; 12. Gas detector; 13. Inner and outer flanges; 14. Top void chamber; 15. Lower cavitation vent pipe; 16. Welded plate; 17. Sleeve. Detailed Implementation
[0028] like Figure 1-4 As shown, a novel LNG carrier cavitation venting pipe penetration component includes a top deck 10, an expansion joint 2, and an outer protective sleeve. The expansion joint 2 and the outer protective sleeve are arranged sequentially. The cavitation venting pipe extends through the expansion joint 2 and the outer protective sleeve to below the top deck 10. The expansion joint 2 is fixed to the top deck 10 via a flange and is located above the top deck 10. The outer protective sleeve is fixed to the top deck 10 via a flange and is located below the top deck 10. The outer protective sleeve includes an upper outer protective sleeve 5 and a lower outer protective sleeve 6. When in use, the device ensures the normal venting function of the cavitation venting pipe within the ship. In the event of an accidental LNG or natural gas leak from the pipeline, the external protective sleeve effectively prevents leakage into the headspace and potential hazard.
[0029] The cavitation venting system includes an upper cavitation venting pipe 1 and a lower cavitation venting pipe 15. The upper cavitation venting pipe 1 and the lower cavitation venting pipe 15 are connected by a threaded flange at the top of the lower cavitation venting pipe 15. The upper cavitation venting pipe 1 extends into the expansion joint 2 and is fixed to the expansion joint 2 via inner and outer flanges 13. The expansion joint 2 above the top deck 10 is made of stainless steel and should meet the requirement of low temperature resistance of -196℃.
[0030] The top deck 10 is equipped with a lower welded component 4, and the expansion joint 2 is fixedly connected to the lower welded component 4. The top deck 10 is equipped with an upper welded component 3, and the outer protective sleeve is fixedly connected to the upper welded component 3. The expansion joint 2 is provided to prevent stress concentration and pipeline damage caused by the deformation of the vent pipe not matching the top deck 10.
[0031] The outer protective sleeve consists of an upper outer protective sleeve 5 and a lower outer protective sleeve 6, which are connected and fixed by a flange to form a headspace compartment 14. A lower cavitation vent pipe 15 is sealed inside the headspace compartment 14, and polyurethane insulation 8 is installed externally to form protection, preventing LNG or natural gas leakage into the headspace compartment 14 due to damage. The outer protective sleeve should be of a half-type design to ensure proper installation after welding inspection and insulation coating of the inner pipe.
[0032] The lower cavitation vent pipe 15 passes through the welded plate 16 connected to the bottom of the headspace 14. A welding elbow plate 9 is provided at the intersection of the lower cavitation vent pipe 15 and the welded plate 16. Below the welded plate 16 is a connecting sleeve 17. Glass insulation cotton 7 is filled between the inner wall of the sleeve 17 and the lower cavitation vent pipe 15 to prevent localized low temperatures from affecting the mechanical properties of the pipe and structure. The outer wall of the upper outer protective sleeve 5 is provided with a purge port 11 and a gas detector 12. The gas detector 12 probe is non-suction type. The outer wall of the lower outer protective sleeve 6 is provided with a purge port 11. The purge port 11 should typically be connected to a shut-off valve to facilitate the connection of the purge pipe in case of accidental LNG or natural gas leakage, while preventing gas leakage into the headspace 14.
[0033] When this device is in use, the expansion joint 2 in the device can prevent stress concentration caused by the deformation of the cavitation vent pipe and its inconsistency with the top deck, which could lead to pipeline damage. The lower cavitation vent pipe 15 is sealed inside the headspace 14, and the outside is protected by polyurethane insulation 8 to prevent LNG or natural gas from leaking into the headspace 14 due to damage. During use, when natural gas leaks, it can be purged by connecting a nitrogen pipeline through the purge port 11. The polyurethane insulation 8 is used for cold insulation of the cavitation vent pipe. Since the accidentally leaked LNG and natural gas are in a low-temperature state, the material used for the cavitation vent pipe is stainless steel with a low-temperature resistance of -196℃. During use, the gas detector 12 can detect whether there is a dangerous gas leak in the pipe in real time. This device can reduce shipyard costs and ship weight. Compared with the commonly used compartment installation, this device starts from the design source and uses a protective sleeve with a purging function. It is smaller in size and can effectively reduce shipyard costs and empty ship weight.
[0034] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Any modifications and improvements made by those skilled in the art to the technical solutions of the present utility model without departing from the spirit of the present utility model should be included within the scope of protection defined by the claims of the present utility model.
Claims
1. A novel LNG carrier cavitation vent pipe penetration component, comprising a top deck, an expansion joint, and an outer protective sleeve, characterized in that: The expansion joint and outer protective sleeve are arranged in sequence. The cavitation vent pipe passes through the expansion joint and the outer protective sleeve and extends to the bottom of the top deck. The expansion joint is fixed to the top deck by a flange and is located above the top deck. The outer protective sleeve is fixed to the top deck by a flange and is located below the top deck. The outer protective sleeve includes an upper outer protective sleeve and a lower outer protective sleeve.
2. The novel LNG ship cavitation vent pipe penetration component according to claim 1, characterized in that: The cavitation vent pipe includes an upper cavitation vent pipe and a lower cavitation vent pipe. The upper cavitation vent pipe and the lower cavitation vent pipe are connected by a connecting flange at the top of the lower cavitation vent pipe. The connecting flange is a threaded flange.
3. A novel LNG ship cavitation vent pipe penetration component according to claim 2, characterized in that: The upper cavitation vent pipe extends into the expansion joint and is fixed to the expansion joint via inner and outer flanges.
4. A novel LNG ship cavitation vent pipe penetration component according to claim 1, characterized in that: The top deck is provided with a lower welded component, and the expansion joint is fixedly connected to the lower welded component.
5. A novel LNG ship cavitation venting pipe penetration component according to claim 1, characterized in that: The top deck is provided with an upper welded component, and the outer protective sleeve is fixedly connected to the upper welded component.
6. A novel LNG ship cavitation venting pipe penetration component according to claim 5, characterized in that: The outer protective sleeve includes an upper outer protective sleeve and a lower outer protective sleeve, which are connected and fixed by a flange to form a headspace compartment. The lower cavitation vent pipe is sealed inside the headspace compartment, and polyurethane insulation is installed on the outside to form protection and prevent LNG or natural gas from leaking into the headspace compartment due to damage.
7. A novel LNG ship cavitation venting pipe penetration component according to claim 6, characterized in that: The lower part of the lower cavitation vent pipe passes through the welding plate connected to the bottom of the top cavity. At the intersection of the lower cavitation vent pipe and the welding plate, there is a welding elbow plate. Below the welding plate is a connecting sleeve. The inner wall of the sleeve and the lower cavitation vent pipe are filled with glass insulating cotton.
8. A novel LNG ship cavitation vent pipe penetration component according to claim 6, characterized in that: The outer wall of the upper outer protective sleeve is provided with a purge port and a gas detector, and the outer wall of the lower outer protective sleeve is provided with a purge port.