A collapsible ventilating mast for a methanol fuel powered boat

Abstract

The application discloses a kind of for methanol fuel power ship's collapsible ventilation mast, including ventilation pipe, mast pipe, the connecting structure of communication ventilation pipe and mast pipe, the drive structure of drive mast pipe relative to ventilation pipe rotation;Connecting structure includes with ventilation pipe communication rotating outer tube, with mast pipe communication rotating inner tube;Ventilation pipe passes through deck and is communicated with rotating outer tube, rotating outer tube is connected with deck by base, rotating inner tube is driven under the drive of drive structure relative to rotating outer tube rotation.The application solves the problem that ventilation mast cannot realize height-limiting navigation, and methanol vapor leakage caused by using flexible hose when collapsing.

Description

Technical Field

[0001] This invention belongs to the field of marine fuel systems and marine safety equipment, and particularly relates to a retractable ventilated mast for methanol-fueled ships. Background Technology

[0002] With the global shipping industry's trend towards green and low-carbon transformation, methanol, with its advantages of being low-carbon and environmentally friendly, easy to store and transport as a liquid at room temperature, and compatible with the retrofitting of existing ship diesel engines, has become a core solution for clean alternatives to powering inland and coastal vessels, and the application scale of methanol-fueled ships continues to expand.

[0003] Methanol is volatile, flammable, and explosive. Fuel tanks require vent masts to balance the positive and negative pressures within the tank, safely venting volatile methanol vapors and preventing damage to the tank hull due to pressure differentials. This also prevents vapor accumulation on the deck, which could lead to combustion and explosion. According to maritime safety regulations, the vent of the vent mast must be at a certain safe height above the deck; therefore, conventional vent masts have a relatively high overall structural height.

[0004] Existing ventilated mast technology suffers from multiple drawbacks, making it difficult to adapt to the needs of methanol-powered vessels. Traditional ventilated masts are mostly fixed vertical structures with no height adjustment, increasing the risk of collisions when vessels pass under bridges, locks, or height-restricted docks, forcing vessels to detour or adjust their navigation plans, severely limiting operational flexibility. Furthermore, some tilting ventilated masts use flexible hoses to connect the air passages; ordinary hoses are prone to cracking due to bending and aging. Methanol vapor also has a corrosive and swelling effect on rubber and conventional polymer materials, accelerating hose deterioration and easily leading to methanol vapor leaks, posing a serious safety hazard. Finally, the sealing reliability of the rotating hinge parts in existing tilting structures is insufficient. Conventional seals degrade rapidly after repeated rotation and wear, easily leaking methanol vapor during rotation. Additionally, repairing the seals requires disassembling the entire mechanism, resulting in high maintenance costs and making it difficult to adapt to high-frequency, height-restricted navigation scenarios. Summary of the Invention

[0005] The purpose of this invention is to provide a reversible ventilated mast for methanol-fueled ships, so as to solve the technical problem that existing ventilated masts for methanol-fueled ships cannot simultaneously achieve both height-restricted navigation flexibility and airtight safety and reliability of rotating parts.

[0006] To achieve the above objectives, the specific technical solution of the present invention for a tiltable ventilated mast for a methanol-fueled ship is as follows:

[0007] A tiltable ventilated mast for a methanol-fueled ship includes a vent pipe, a mast pipe, a connecting structure connecting the vent pipe and the mast pipe, and a drive structure for driving the mast pipe to rotate relative to the vent pipe.

[0008] The connecting structure includes a rotating outer tube communicating with the vent pipe and a rotating inner tube communicating with the mast pipe; the rotating inner tube and the rotating outer tube are open at one end, the outer diameter of the open end of the rotating inner tube matches the inner diameter of the open end of the rotating outer tube, and the open end of the rotating inner tube is sleeved inside the open end of the rotating outer tube.

[0009] The vent pipe passes through the deck and communicates with the rotating outer pipe. The rotating outer pipe is connected to the deck through a base. The rotating inner pipe rotates relative to the rotating outer pipe under the drive of the drive structure.

[0010] As a further improvement of the present invention, the mast passes through the rotating inner tube, one end of which is connected to the drive structure, and the other end is provided with a pressure valve.

[0011] As a further improvement of the present invention, an annular packing gap is formed between the rotating inner tube and the rotating outer tube. The packing gap is filled with sealing packing. The gland is pressed tightly against the outer wall of the rotating inner tube and enters the packing gap to squeeze the sealing packing. The gland is connected to the rotating outer tube by bolts.

[0012] As a further improvement of the present invention, a protrusion is provided around the outer side of the opening end of the rotating inner tube, and the outer diameter of the protrusion matches the inner diameter of the rotating outer tube; a bend is provided on the inner wall of the rotating outer tube corresponding to the end of the rotating inner tube, and the rotating inner tube enters the rotating outer tube and abuts against the bend; a filler gap is formed between the outer wall of the rotating inner tube located behind the protrusion and the inner wall of the rotating outer tube.

[0013] As a further improvement of the present invention, the gland includes an annular extrusion portion corresponding to the packing gap and a connecting portion bent outward relative to the extrusion portion; the bolt passes through the connecting portion and connects to the open end of the rotating outer tube, and the extrusion portion enters the packing gap and cooperates with the protrusion to press the sealing packing.

[0014] As a further improvement of the present invention, the driving structure is a hydraulic cylinder structure, including a cylinder body and a piston rod, wherein the closed end of the cylinder body is rotatably connected to the deck, and the extended end of the piston rod is rotatably connected to the mast.

[0015] As a further improvement of the present invention, the closed end of the cylinder body is hinged and fixed to the deck, and the extended end of the piston rod is hinged to the pipe wall at the lower part of the mast.

[0016] As a further improvement of the present invention, the rotation angle range of the inner rotating tube relative to the outer rotating tube is 0°-90°.

[0017] As a further improvement of the present invention, the sealing filler is polytetrafluoroethylene or anthracene tetrafluoroethylene.

[0018] As a further improvement of the present invention, the cap is a split structure with two parts that wrap around and fit against the outer wall of the rotating inner tube.

[0019] Beneficial effects:

[0020] This invention drives the inner rotating tube to rotate relative to the outer rotating tube through a driving structure, which can drive the mast to flip and adjust its posture. When ships pass through areas with restricted clearance such as bridges, locks, and height-restricted docks, the height of the mast can be reduced to avoid collisions, eliminating the need for detours or adjustments to navigation plans, and effectively improving the ship's route adaptability and operational flexibility.

[0021] The structure employs a rotating inner tube that fits inside a rotating outer tube, enabling a rotating air passage connection between the vent pipe and the mast pipe. The overall design is a rigid pipe rotating fit, which, compared to the reversible structure of flexible hoses, offers higher structural strength and more stable air passage connection, making it suitable for complex operating conditions such as vibrations and wave impacts during ship navigation.

[0022] The rotating outer tube is fixed to the deck via a base, and the vent pipe passes directly through the deck and connects to the rotating outer tube. The force of the rotation operation is borne and dispersed by the base, avoiding direct force deformation of the pipeline. The overall support structure is stable, which can ensure the structural reliability of the rotating mechanism for long-term operation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the vertical state of a retractable ventilated mast for a methanol-fueled ship according to the present invention.

[0024] Figure 2 This is a schematic diagram of a foldable, permeable mast used in methanol-fueled ships, in its collapsed state.

[0025] Figure 3 for Figure 1 AA section view;

[0026] Figure 4 for Figure 3 Enlarged detail of B;

[0027] The markings in the diagram are as follows: 1. Vent pipe; 2. Mast pipe; 21. Pressure valve; 3. Connecting structure; 31. Rotating outer pipe; 311. Bend; 32. Rotating inner pipe; 321. Protrusion; 33. Packing gap; 34. Gland; 341. Extrusion section; 342. Connecting part; 35. Bolt; 4. Drive structure; 41. Cylinder; 42. Piston rod; 5. Base; 6. Deck. Detailed Implementation

[0028] To better understand the purpose, structure, and function of this invention, the following detailed description of a retractable ventilated mast for a methanol-fueled ship, in conjunction with the accompanying drawings, is provided.

[0029] Implementation example:

[0030] like Figure 1 and 2 As shown, a tiltable ventilated mast for a methanol-fueled ship is installed on the deck 6 of the vessel. It includes a vent pipe 1, a mast pipe 2, a connecting structure 3 connecting the vent pipe 1 and the mast pipe 2, and a drive structure 4 that drives the mast pipe 2 to rotate relative to the vent pipe 1. The vent pipe 1 connects to the methanol fuel tank venting system to balance the fuel tank pressure and safely release methanol vapors. The fixed end of the connecting structure 3 is mounted on the deck 6 via a base 5, and the rotating end is rigidly connected to the mast pipe 2. The drive structure 4 can drive the mast pipe 2 and the rotating end of the connecting structure 3 to rotate synchronously. The rotation angle range of the inner rotating pipe 32 relative to the outer rotating pipe 31 is 0°-90°, allowing the mast pipe 2 to operate vertically and tilt horizontally, respectively.

[0031] The vent pipe 1 is made of stainless steel and is installed vertically through the deck 6. The lower end of the pipe is connected to the internal vent pipe of the ship's methanol fuel tank, and the upper end is sealed and welded to the rotating outer pipe 31 of the connecting structure 3. It serves as an air passage between the fuel tank and the vent mast to transport methanol vapor that evaporates inside the tank.

[0032] The base 5 is a base in the form of elbow plate splicing, which is fixed to the surface of the ship deck 6 by bolts. The side is rigidly connected to the outer wall of the rotating outer tube 31. It is used to bear the overall weight of the connecting structure 3 and the mast tube 2 as well as the force during the rotation process, so as to avoid the pipeline being directly deformed by the force and ensure the operational stability of the rotating structure.

[0033] like Figure 3 and 4 As shown, the connecting structure 3 includes a rotating outer tube 31, a rotating inner tube 32, a sealing filler, a gland 34, and a bolt 35.

[0034] The rotating outer tube 31 is a hollow tubular structure with one open end. The lower end is closed and sealed to the upper end of the vent tube 1. The entire tube is fixed to the deck by the base 5 and remains stationary during operation. Near the open end, the inner wall of the rotating outer tube 31 has a ring of inwardly protruding bends 311, which serve as an axial limiting step for the rotating inner tube 32 and limit the insertion depth of the rotating inner tube.

[0035] The rotating inner tube 32 is a hollow tubular structure with one open end. The outer diameter of the open end matches the inner diameter of the open end of the rotating outer tube 31, and it is integrally fitted into the internal cavity of the rotating outer tube 31. A protrusion 321 is arranged around the outer wall of the open end of the rotating inner tube 32, and the outer diameter of the protrusion 321 matches the inner diameter of the rotating outer tube 31. When the rotating inner tube 32 extends into the rotating outer tube 31, the end face of the protrusion 321 abuts against the bent portion 311, forming an axial limit. The outer wall of the rotating inner tube 32 behind the protrusion 321 forms a closed annular packing gap 33 with the inner wall of the rotating outer tube 31, which is used to accommodate sealing packing. The mast 2 vertically penetrates the rotating inner tube 32 and is sealed and welded to the rotating inner tube 32 as a whole, and can rotate synchronously around the axis with the rotating inner tube.

[0036] The sealing packing is filled in the annular packing gap 33. It is made of polytetrafluoroethylene material that is resistant to methanol corrosion and has excellent resistance to methanol vapor corrosion and wear resistance. After being compressed, the sealing packing fills the entire annular gap. During the rotation of the rotating inner tube, the rotating mating surface is always kept airtight, which effectively prevents methanol vapor from leaking from the rotating joint and meets the high sealing safety requirements of methanol fuel ships.

[0037] The gland 34 is an annular pressing component with a split, interlocking structure. It consists of two semi-annular parts that encircle and fit against the outer wall of the rotating inner tube 32. During installation or disassembly, it can be assembled directly without needing to be inserted through the mast end, significantly reducing the maintenance difficulty of subsequent sealing packing replacement. Maintenance can be completed without disassembling the entire rotating pipeline structure. It includes an annular extrusion part 341 corresponding to the position of the packing gap 33, and a connecting part 342 that bends outward relative to the extrusion part 341. The radial dimension of the extrusion part 341 is adapted to the packing gap 33, extending into the packing gap 33 from the open end of the rotating outer tube 31, with its front end directly pressing against the sealing packing. The connecting part 342 is an annular flange structure that rests against the open end face of the rotating outer tube 31 and is fixedly connected to the end of the rotating outer tube 31 by multiple sets of bolts 35. When the bolt 35 is tightened, the extrusion part 341 can be pushed into the packing gap and cooperate with the protrusion 321 of the rotating inner tube to jointly compress the sealing packing. The compression amount of the sealing packing can be adjusted by adjusting the tightness of the bolt to adapt to different sealing performance requirements.

[0038] The mast 2 is a rigid stainless steel straight pipe that vertically penetrates the closed end of the rotating inner pipe 32 and is sealed and welded to the rotating inner pipe 32. The lower end of the pipe is connected to the drive structure 4, and the upper end is the exhaust end, with a pressure valve 21 installed at the end. The pressure valve 21 is a vacuum-pressure composite valve used to automatically balance the internal and external pressures of the methanol fuel tank: when the pressure inside the tank is higher than the external set threshold, the positive pressure end of the valve opens, venting the methanol vapor inside the tank to the outside; when the pressure inside the tank is lower than the external set threshold, the negative pressure end of the valve opens, drawing in outside air to replenish the pressure inside the tank, preventing the fuel tank from expanding or collapsing due to pressure difference; at the same time, it guides the exhaust to a safe height at the top of the mast to diffuse, preventing methanol vapor from accumulating in the deck working area and reducing the risk of combustion, explosion, and poisoning.

[0039] The drive structure 4 employs a hydraulic cylinder structure, including a cylinder body 41 and a piston rod 42, to provide power for the rotation of the mast. The closed end of the cylinder body 41 is hinged and fixed to the deck 6, allowing it to swing slightly around the hinge point; the extended end of the piston rod 42 is hinged to the lower part of the mast 2's tube wall. When the piston rod extends or retracts, a thrust or pull force can be applied through the hinge point, causing the mast 2 and the rotating inner tube 32 to rotate together around the axis of the rotating outer tube, smoothly completing the mast's tilting and resetting actions. The drive structure 4 has a locking function, ensuring that the mast 2 is reliably fixed in both vertical and tilted states, preventing accidental rotation due to wind vibration or ship swaying.

[0040] In this embodiment, the total height of the mast 2 in the vertical state is 4 meters. The sum of the height of the portion of the ship's vent pipe 1 extending above the deck surface, the rotating outer pipe 31, the rotating inner pipe 32, the mast 2, and the pressure valve 21 is 4 meters. When the mast 2 is tilted, its height does not exceed 0.7 meters, determined by the height of the base 5, the rotating outer pipe 31, the rotating inner pipe 32, and the hydraulic cylinder. At this time, the mast 2 is in a horizontal state, extending horizontally in its length direction, and does not occupy vertical space, effectively solving the problem of ships passing through bridges, docks, and other limited height spaces.

[0041] When using, such as Figure 1 As shown, during normal navigation, the piston rod 42 of the drive structure 4 is in the retracted position, and the mast 2 remains vertical at 0°. The volatile vapors in the methanol fuel tank enter the gas passage of the connecting structure 3 through the vent pipe 1, and are then transported to the top through the mast 2. Pressure valve 21 regulates the pressure and exhausts the vapors. At this time, the overall height of the mast meets the safety emission height specifications for the ship's ventilation system, ensuring the normal operation of the ventilation function. Figure 2As shown, when a ship passes through areas with restricted clearance, such as bridges, locks, and height-restricted wharves, the hydraulic cylinder injects oil, pushing the piston rod 42 to extend. This causes the mast 2 and the rotating inner tube 32 to rotate 90° around their axis synchronously, turning the mast into a horizontal, tilted position. This significantly reduces the overall height, effectively preventing collisions with height-restricted structures and ensuring the ship's smooth passage through the restricted area. After passage is complete, the cylinder injects oil in the opposite direction, retracting the piston rod and returning the mast to a vertical position, thus restoring normal ventilation.

[0042] This invention features a rotatable and tiltable design, allowing for flexible adjustment of the mast height. It perfectly adapts to navigation scenarios such as bridges, locks, and height-restricted wharves, avoiding the risk of collisions with structures and eliminating the need for detours or adjustments to navigation plans, significantly improving the flexibility and adaptability of ship operations. The rigidly fitted rotary sealing structure, combined with methanol-resistant sealing packing, maintains an airtight seal throughout the rotation, completely avoiding the defects of flexible hoses that are prone to aging and leakage due to methanol vapor corrosion, meeting the high sealing safety standards for methanol-fueled ships. The gland adjusts the packing clamping force via bolts, allowing for direct pre-tightening compensation after seal wear, extending the service life of the seals. The split-type mating gland allows for packing replacement without disassembling the entire pipeline, facilitating maintenance and significantly reducing downtime for repairs. The hydraulic cylinder drive system, with hinged ends, provides smooth and seamless transmission, adapting to complex navigation conditions such as ship vibration and wave impact, and ensuring high overall structural reliability.

[0043] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A retractable ventilated mast for a methanol-fueled ship, characterized in that, It includes a vent pipe, a mast, a connecting structure connecting the vent pipe and the mast, and a drive structure for driving the mast to rotate relative to the vent pipe; The connecting structure includes a rotating outer tube communicating with the vent pipe and a rotating inner tube communicating with the mast pipe; the rotating inner tube and the rotating outer tube are open at one end, the outer diameter of the open end of the rotating inner tube matches the inner diameter of the open end of the rotating outer tube, and the open end of the rotating inner tube is sleeved inside the open end of the rotating outer tube. The vent pipe passes through the deck and communicates with the rotating outer pipe. The rotating outer pipe is connected to the deck through a base. The rotating inner pipe rotates relative to the rotating outer pipe under the drive of the drive structure.

2. The inverted ventilated mast for a methanol-fueled ship according to claim 1, characterized in that, The mast passes through the rotating inner tube, with one end connected to the drive structure and the other end equipped with a pressure valve.

3. The inverted ventilated mast for a methanol-fueled ship according to claim 1, characterized in that, An annular packing gap is formed between the rotating inner tube and the rotating outer tube. The packing gap is filled with sealing packing. The gland is pressed tightly against the outer wall of the rotating inner tube and enters the packing gap to squeeze the sealing packing. The gland is connected to the rotating outer tube by bolts.

4. The inverted ventilated mast for a methanol-fueled ship according to claim 3, characterized in that, A protrusion is provided around the outer side of the open end of the rotating inner tube, and the outer diameter of the protrusion matches the inner diameter of the rotating outer tube; a bend is provided on the inner wall of the rotating outer tube corresponding to the end of the rotating inner tube, and the rotating inner tube enters the rotating outer tube and abuts against the bend; a filler gap is formed between the outer wall of the rotating inner tube behind the protrusion and the inner wall of the rotating outer tube.

5. The inverted ventilated mast for a methanol-fueled ship according to claim 4, characterized in that, The gland includes an annular extrusion portion corresponding to the packing gap and a connecting portion bent outward relative to the extrusion portion; the bolt passes through the connecting portion and connects to the open end of the rotating outer tube, and the extrusion portion enters the packing gap and cooperates with the protrusion to press the sealing packing.

6. The inverted ventilated mast for a methanol-fueled ship according to claim 2, characterized in that, The drive structure is a hydraulic cylinder structure, including a cylinder body and a piston rod. The closed end of the cylinder body is rotatably connected to the deck, and the extended end of the piston rod is rotatably connected to the mast.

7. The inverted ventilated mast for a methanol-fueled ship according to claim 6, characterized in that, The cylinder body is hinged and fixed to the deck at the closed end, and the piston rod is hinged to the lower part of the mast wall at the extended end.

8. The inverted ventilated mast for a methanol-fueled ship according to claim 1, characterized in that, The rotation angle range of the inner rotating tube relative to the outer rotating tube is 0°-90°.

9. The inverted ventilated mast for a methanol-fueled ship according to claim 3, characterized in that, The sealing filler is polytetrafluoroethylene or anthracene tetrafluoroethylene.

10. The inverted ventilated mast for a methanol-fueled ship according to claim 3, characterized in that, The cap is a split structure with two parts that wrap around and fit against the outer wall of the rotating inner tube.

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