Coupling for liquefied gas

Abstract

A coupling (1) for liquefied gas comprises a first part (10) and a female part (40) which are coupled to each other by inserting the first part (10) into a second part (40). An internal liquefied gas conduit is fluidly connected to convey liquefied gas through the coupler (1). A valve (42) is movable between a first position in which the liquefied gas is prevented from being transmitted through the coupler and a second position in which the liquefied gas is allowed to be transmitted through the coupler. In the event that the parts (10, 40) are interconnected, the coupling has a first operating state in which no liquefied gas is transmitted through the coupling and a second operating state in which liquefied gas is allowed to flow through the coupling. An improved safety coupling is provided by providing an actuator (28a, 30) outside the internal liquefied gas conduit (26).

Description

Technical Field

[0001] The present invention generally relates to connectors, and more particularly to a connector for transporting cryogenic media through a vacuum insulated tube or hose line, the connector having a poppet that can be moved in an axial direction relative to the connector plug using a pneumatic or hydraulic supply device, wherein the pneumatic or hydraulic supply device is located outside the vacuum insulated tube or hose line with any gaseous or liquid medium, thereby allowing the pipeline in the connector plug (e.g., a single poppet valve or multiple poppet valves) to be opened on the other side of the pipeline to transport the cryogenic medium. Background Art

[0002] Under the zero emission target or CO2 neutral future target of global environmental issues, clean energy such as hydrogen and natural gas play more and more roles in meeting the increasing demand. One example is that clean liquefied gas (especially hydrogen) produced by solar energy, wind and other clean energy sources is more in need of transportation in liquid phase due to its lower volume. On the other hand, liquefied gas is considered as a fuel for long-distance transportation (such as trucks, ships, airplanes and rockets) due to its high energy and high density fuel.

[0003] In cryogenic applications, temperature changes can quickly become dangerous, especially if liquefied gases reach boiling temperature, causing them to expand rapidly. An example is liquid hydrogen (LH2) which needs to be kept below -253°C at atmospheric pressure to remain liquid. LH2 at boiling point can expand about 800 times in volume to hydrogen gas (GH2) at ambient temperature, which creates dangerous pressures. As is known, this cryogenic medium can only be transported or refueled with appropriate insulation measures, such as vacuum insulated pipes or hose lines.

[0004] In particular, for bunkering cryogenic liquefied gases, especially LH2, the connector is a critical and vulnerable component, where thermal bridges and dead spaces containing, for example, air may provide dangerous changes. For example, at atmospheric pressure, LNG condenses into liquid at temperatures below about -160°C, oxygen condenses into liquid oxygen at temperatures of about -183°C, nitrogen condenses into liquid nitrogen LN2 at about -195°C, and hydrogen condenses into liquid hydrogen LH2 at temperatures below about -253°C. In order to maintain, when liquefied gas is transported as fuel, it is important that no foreign particles (including condensed liquid oxygen, liquid nitrogen or solid oxygen, solid nitrogen) are introduced into the storage (e.g., fuel unit). Potential leakage of H2 at the dead space with condensed liquid oxygen may also cause an explosion.

[0005] Liquefied gas is used for different purposes, but regardless of the purpose, efficiency and safety are important factors. To provide one example among many, liquefied gas can be used as a fuel and needs to be transferred from a fuel station to, for example, a truck. Although such transfers are well known in the art, there are disadvantages in the art that reduce efficiency. For example, open connectors do not have a poppet. This type of connector will require purging the entire pipeline with an inert gas to first test for leaks and then empty it.

[0006] Insulation is a way to avoid heat loss during the transport of cryogenic media, which also means that less "cold" will be transferred to the outside of the operating area. Effective insulation means that the system does not have to work as hard to maintain the operating temperature of the unit, thereby reducing energy consumption. One known vacuum insulation is to use various insulating materials, such as aluminum foil wrapped inside a vacuum chamber. Summary of the invention

[0007] The object of the present invention is to provide a coupling for liquefied gas to quickly connect and disconnect a hose without requiring additional tools and without spillage, and in which reliability and safety are primary considerations.

[0008] According to a first aspect of the present invention, there is provided a coupling for liquefied gas, the coupling comprising: a first male part and a second female part, the first male part and the second female part being connected to each other by inserting the first part into the second part, wherein the first part and the second part each comprise an internal liquefied gas pipeline for fluid connection at a connection point to transmit liquefied gas through the coupling; a valve movable between a first position and a second position, in which the transmission of liquefied gas through the coupling is blocked, and in which the transmission of liquefied gas through the coupling is allowed; an actuator for moving the valve between the first position and the second position, wherein, in the case where the first part and the second part are interconnected, the coupling has a first operating state and a second operating state, in which no liquefied gas is transmitted through the coupling, and in which the liquefied gas is allowed to flow through the coupling, the coupling being characterized in that the actuator is arranged outside the internal liquefied gas pipeline. In this way, the influence of the temperature of the transmission medium is much smaller.

[0009] In a preferred embodiment, the coupling is provided with insulation, preferably vacuum insulation.

[0010] In a preferred embodiment, the actuator is arranged outside the insulating body.

[0011] In a preferred embodiment, the actuator comprises a chamber for exerting pressure on a rigid mechanical connection to the displacement piston.

[0012] In a preferred embodiment, the chamber is a pneumatic or hydraulic chamber.

[0013] In a preferred embodiment, the coupling is for cryogenic liquefied gas.

[0014] According to a second aspect of the present invention, a nozzle for a connector according to the present invention is provided, the nozzle comprising: a first male part, the first male part being connectable to a second female part of the connector, the first part and the second part being connected to each other by inserting the first part into the second part, the first part comprising an internal liquefied gas pipeline, the internal liquefied gas pipeline being used for fluid connection to transmit liquefied gas through the connector, wherein, when the first part and the second part are interconnected, the connector has a first operating state and a second operating state, in the first operating state, no liquefied gas is transmitted through the connector, and in the second operating state, liquefied gas is allowed to flow through the connector, the nozzle being characterized in that the actuator is arranged outside the internal liquefied gas pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0016] Figure 1 is in the connected position Figure 1 a cross-sectional view of a coupling of wherein no flow is passing through the coupling;

[0017] Figure 2 yes Figure 1 A cross-sectional view of the coupling after connecting and locking the parts of the coupling, at which time purging can begin; and

[0018] Figure 3 yes Figure 1 A cross-sectional view of the coupling after connection and with full flow. DETAILED DESCRIPTION

[0019] In the following, a detailed description of different embodiments of the solution is disclosed with reference to the accompanying drawings. All examples herein should be considered as part of the general description and can therefore be combined in any general terms. Individual features of the various embodiments and aspects can be combined or exchanged, unless such combination or exchange is obviously inconsistent with the overall function of the device or method.

[0020] In this specification, the term coupling will denote the two halves of a connection unit with an internal valve, comprising a female part in the form of a socket (also called a tank unit or adapter) and a male part in the form of a nozzle (also called a hose unit or coupling). The socket is primarily vacuum mounted on a transport unit such as a tank truck, rail vehicle or receiving vessel, while the nozzle is primarily vacuum mounted on a supply unit such as a flexible hose from a fuel station, a loading arm from a storage tank, a supply tanker or a bunkering ship.

[0021] Now go to Figure 1 , shows a coupling, generally designated 1, comprising a first male part in the form of a nozzle 10 and a second female part in the form of a socket 40, which are coupled to each other by inserting the nozzle 10 into the socket 40. The interconnection between the nozzle 10 and the socket 40 is achieved by first inserting the nozzle 10 into the socket 40 and then rotating the nozzle 10 about its central axis by turning a handle 12 attached to the nozzle 10. There will be mutual rotation between the nozzle 10 and the socket 40 as the socket 40 is fixed against rotation by its attachment to the receiving vessel.

[0022] In order to sense the position of the nozzle 10 relative to the socket 40, an interconnection sensor 14 is provided in the nozzle 10. In the preferred embodiment, the interconnection sensor 14 is arranged on or attached to the nozzle 10 engaged in the socket 40. The locking means and the groove together form a bayonet joint, as known in the art. The interconnection sensor 14 can be an inductive sensor, but other options are also possible, such as a proximity sensor or a magnetic sensor.

[0023] exist Figure 1 In the interconnected position shown, the nozzle 10 and the socket 40 are not locked to each other. In other words, the operator can disengage the nozzle 10 from the socket 40 by reversing the interconnection process. For safe operation, a lock sensor 16 is provided that senses whether the locking mechanism 18 has been activated. The locking mechanism ensures that the nozzle 10 cannot be disengaged from the socket 40.

[0024] The valve sensor 20 is arranged to detect the position of a valve device 42, which is arranged in the socket and can be moved between a first position, in which the transmission of liquefied gas through the connector 1 is blocked, and a second position, in which the transmission of liquefied gas through the connector is allowed. In the embodiment shown in the figure, the valve device 42 includes a poppet valve arranged in sequence in the flow path. For safety reasons, it must be ensured that the flow of liquefied gas does not start before the nozzle 10 and the socket 40 are locked to each other. However, in another embodiment, the locking mechanism is usually closed, that is, the nozzle 10 and the socket 40 are locked to each other by default.

[0025] exist Figure 2, a coupling is shown in which the nozzle 10 and the socket 40 are locked to each other by a locking mechanism 18. This means that the operation of transmitting liquefied gas can be started. The operation starts with a so-called purge operation, in which the chamber between the nozzle 10 and the socket 40 is flushed with a suitable gas (e.g. H2) to ensure that no oxygen remains therein. In this regard, the valve sensor 20 gives a clear signal for the purge position, in which the cold seal is not engaged with the socket 40. Only when the space 24 between the nozzle 10 and the socket 40 has been flushed, the liquefied gas in the gas duct 26 of the nozzle 10 is allowed to start flowing into the socket 40.

[0026] exist Figure 3 , the coupling 1 is shown when liquefied gas flows through the gas duct 26 of the nozzle 10 and the gas duct 46 of the socket 40. As can be seen in this figure, the valve 42 has been pushed from a position in which the valve piston has disengaged from the valve seat, thereby allowing flow into the gas duct 46 of the socket 40. This displacement of the valve 42 of the socket is affected by the displacement of the displacement piston 28 provided in the nozzle 10.

[0027] The displacement of the piston 28 is achieved by increasing the pressure in a displacement chamber 30 arranged outside the gas duct 26 of the nozzle 10 and preferably outside the insulation, in this case the vacuum insulation. In other words, the pneumatic or hydraulic supply device is outside the vacuum insulation pipe or hose line with any gaseous or liquid medium. In a preferred embodiment, the gas pressure in the displacement chamber 30 is increased to 15 bar to 20 bar in order to achieve the displacement. The gas in the displacement chamber 30 exerts pressure on the shoulder 28a rigidly mechanically connected to the displacement piston 28, thereby displacing the shoulder 28a and thus the displacement piston 28 to the left in the figure. The fact that the driving force is completely outside the gas duct 26 avoids the risk of liquid gas mixing with other gases. Instead of a pneumatic solution with gas in the displacement chamber 30, a hydraulic solution is also possible.

[0028] Returning to the sensors 14, 16, 20, the arrangement of these sensors enables a fully automated airflow process once the operator has connected the nozzle 10 to the socket 40. The automated process essentially comprises the following steps:

[0029] - manually interconnecting the nozzle 10 and the socket 40 so that the nozzle 10 and the socket 40 are in an interconnected state;

[0030] -Detect interconnection status;

[0031] - Automatically lock the nozzle 10 to the socket 40;

[0032] -optionally, detecting valve position;

[0033] - Automatically purge the space 24 between the nozzle 10 and the socket 40;

[0034] - Automatically shifting the valve 42 from a first position, in which the transmission of liquefied gas through the coupling 1 is blocked, to a second position, in which the transmission of liquefied gas through the coupling 1 is allowed.

[0035] When the flow of liquefied gas is to be terminated, the process is reversed. In one embodiment of the reverse operation, after the pressure in chamber 30 is released, the spring pushes the valve to the closed position. In this embodiment, the cold seal remains in the sealed position, thereby enabling safe purge of gas trapped in the coupling. Pressure is then applied to the opposite side of chamber 30 to disengage the cold seal.

[0036] Preferred embodiments of a coupling according to the invention and of a method of operating such a coupling have been described. It will be appreciated that these embodiments may be modified within the scope of the appended claims without departing from the inventive concept. Thus, a coupling solution with a double valve is shown in the figures. It will be appreciated that the invention is also applicable to other types of valves, such as single valve or multi-valve solutions.

Claims

1. A connector (1) for liquefied gas, the connector (1) comprising: a first part (10) and a second part (40) coupled to each other by inserting the first part (10) into the second part (40), wherein the first part (10) and the second part (40) each include an internal liquefied gas conduit (26, 46) for fluid connection at a connection point to transfer liquefied gas through the coupling (1); a valve (42) movable between a first position, wherein the valve prevents the transfer of liquefied gas through the coupling, and a second position, wherein the valve allows the transfer of liquefied gas through the coupling; an actuator (28a, 30) for moving the valve (42) between the first position and the second position, wherein, when the first part (10) and the second part (40) are interconnected, the coupling has a first operating state in which no liquefied gas is transmitted through the coupling and a second operating state in which liquefied gas is allowed to flow through the coupling, It is characterized in that the actuator (28a, 30) is arranged outside the internal liquefied gas pipeline (26).

2. A coupling according to claim 1, comprising an insulator, preferably a vacuum insulator.

3. The coupling according to claim 2, wherein: The actuator (28a, 30) is arranged outside the insulator.

4. The coupling according to any one of claims 1 to 3, wherein: The actuator comprises a chamber (30) for exerting pressure on a rigid mechanical connection to a displacement piston (28).

5. The coupling according to claim 3, wherein: The chamber (30) is a pneumatic or hydraulic chamber.

6. The coupling according to any one of claims 1 to 5, wherein: The connector (1) is used for cryogenic liquefied gas.

7. The coupling according to any one of claims 1 to 6, wherein: The connector (1).

8. A nozzle for a coupling according to any one of claims 1 to 6, the nozzle comprising: a first part (10) connectable to a second part (40) of the coupling, the first part and the second part being coupled to each other by inserting the first part (10) into the second part (40), The first part (10) comprises an internal liquefied gas conduit for fluid connection to transfer liquefied gas through the coupling (1), wherein, when the first part (10) and the second part (40) are interconnected, the coupling has a first operating state in which no liquefied gas is transmitted through the coupling and a second operating state in which liquefied gas is allowed to flow through the coupling, It is characterized in that the actuator (28a, 30) is arranged outside the internal liquefied gas pipeline (26).

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