KR20210133724A - Backflow prevention valve set of the gas purging system and gas purging system of ship having same - Google Patents

Abstract

The present invention relates to a backflow prevention valve set of a gas purging system installed on a purging line to supply inert gas for the purpose of purging a gas pipe. The backflow prevention valve set includes: an integrated body; a first flow path formed in the integrated body, and providing a passage through which inert gas is introduced and discharged; a second flow path branched from the first flow path to discharge leaking gas; first and second blocking valves installed sequentially from an upstream side of the first flow path to dually open or block the first flow path; a check valve installed on a downstream side of the second blocking valve on the first flow path to cause the flow of the inert gas in the first flow path to flow in only one direction; and a bleed valve installed on the second flow path branched from the first flow path between the first blocking valve and the second blocking valve to remove residual pressure between the first blocking valve and the second blocking valve when the first blocking valve and the second blocking valve are blocked. The first blocking valve, the second blocking valve, the check valve and the bleed valve are integrated as one valve set through the integrated body. Therefore, the present invention is capable of securing more stability and improving productivity in shipbuilding.

Description

BACKFLOW PREVENTION VALVE SET OF THE GAS PURGING SYSTEM AND GAS PURGING SYSTEM OF SHIP HAVING SAME}

The present invention relates to a non-return valve set of a gas purging system, and more particularly, in a system for purging residual gas remaining inside an engine system using fuel gas, to prevent backflow of fuel gas from the engine It relates to a non-return valve set of a gas purging system in which the logic for the non-return control is simplified by integrating the valves installed for this purpose into one set.

In general, combustion devices such as engines installed in various ships used oils such as Marine Diesel Oil (MDO) and Heavy Fuel Oil (HFO) as fuel. However, such fuel oil has been the main culprit in causing environmental pollution due to greenhouse gases and various harmful substances generated during combustion. In addition, when oil prices rise due to factors such as depletion of fossil fuels or international political instability, problems in ship operation such as fuel costs soar will also occur.

Therefore, in recent years, a method of using electricity or using a clean fuel such as LNG (Liquefied Natural Gas) or LPG (Liquefied Peroleum Gas) for propulsion of a ship is being considered.

In addition, according to recent technology development, a DF engine (Dual Fuel Engine) that can use both fuel oil and fuel gas as fuel has been developed and used. It is a kind of hybrid engine that is used as fuel and is an eco-friendly engine that can dramatically reduce fuel consumption, carbon emissions, and operating expenses.

For example, the ME-GI engine is a 2-stroke high-pressure gas injection engine that can use both heavy oil and natural gas as fuel. Compared to a diesel engine with the same output, the ME-GI engine reduces the emission of pollutants by 23% carbon dioxide and 80% nitrogen compounds, It is attracting attention as a next-generation eco-friendly engine that can reduce sulfur compounds by more than 95%.

On the other hand, when it is desired to stop the operation of the engine using fuel gas as fuel for a long time or to maintain the internal system, or to replace the fuel used in the engine from fuel gas to fuel oil, fuel gas is supplied to the engine. It is necessary to remove the fuel gas remaining in the engine system including the piping system. This is because there is a risk of explosion if flammable fuel gas remains in the system.

Therefore, in a ship equipped with an engine using fuel gas, a gas purging system for discharging fuel gas remaining in the engine system must be installed.

In general, the gas purging system is configured to push and discharge the fuel gas remaining in the engine system using an inert gas such as _{nitrogen (N 2 ).}

1 is a view schematically showing a gas purging system of a conventional ship.

Referring to FIG. 1 , in an engine 1 using fuel gas in a conventional ship, a fuel supply line 2 to which fuel gas is supplied from a fuel storage tank (not shown) and exhaust gas are discharged from the engine 1 . The exhaust lines 3 are connected to each other. A gas valve unit (GVU) 4 is installed on the fuel supply line 2 to control the pressure and flow rate of fuel gas supplied to the engine 1 .

In addition, for the purpose of purging the inside of the engine system, a purging line 6 for injecting nitrogen gas supplied from the nitrogen buffer tank 5 into the fuel supply line 2 is connected.

The gas purging system of a conventional ship may be configured to purify the inside of the fuel supply line 2 and the engine 1 using nitrogen gas supplied from the nitrogen buffer tank 5 .

Specifically, when the purging operation of the engine system is started, the fuel supply valve 2-1 installed on the fuel supply line 2 is blocked, and the purging valve 6-1 installed on the purging line 6 is blocked. is opened and nitrogen stored in the nitrogen buffer tank 5 is injected into the fuel supply line 2 in a gaseous state.

The nitrogen gas injected into the fuel supply line (2) is supplied to the engine (1) through the gas valve unit (4), and the fuel gas remaining in the engine system is pushed by the nitrogen gas and is safely passed through the exhaust line (3). It is discharged to a Safe Area (eg, outside air).

As described above, in the gas purging system of a conventional ship, it can be seen that the purging by nitrogen gas is performed in the order of the gas valve unit (4) → engine (1) → Safe Area.

However, according to the conventional gas purging system as described above, there is a risk that the exhaust line 3 from which the residual gas is purged from the engine system is disposed in the engine room, and is classified as a gas safe zone. In order to provide a vent pipe inside the engine room, there is a disadvantage in that the quantity of YARD increases because double pipe or duct treatment is required.

Korean Patent Publication No. 10-1334146 (2013.11.29)

The technical problem to be achieved by the present invention is to prevent the risk of explosion by changing the design so that the pipe from which the residual gas is discharged during the purging process of the engine system using liquefied gas such as LNG as fuel is not arranged in the engine room as much as possible. An object of the present invention is to provide a gas purging system for ships capable of ensuring stability.

In addition, another technical object of the present invention is to provide a non-return valve set for a gas purging system capable of more reliably preventing reverse flow of LNG gas from an engine in the gas purging system.

In addition, by integrating the valves installed to prevent the reverse flow of LNG gas into one valve set, the logic for the control of backflow prevention is simplified, thereby increasing the use of space in the ship and reducing costs.

According to one aspect of the present invention for achieving the above object, there is provided a non-return valve set of a gas purging system installed on a purging line for supplying an inert gas for the purpose of purging a gas pipe, comprising: an integrated body; a first flow path formed inside the integrated body and providing a passage through which the inert gas is introduced and discharged; a second flow path branching from the first flow path and discharging the leaked gas; a first shut-off valve and a second shut-off valve sequentially installed from an upstream side of the first flow path to double open or block the first flow path; a check valve installed on the downstream side of the second shut-off valve on the first flow path to flow the inert gas in the first flow path in only one direction; and installed on the second flow path branching from the first flow path between the first shut-off valve and the second shut-off valve, the first shut-off valve and the second shut-off valve when the first shut-off valve is shut off; and a bleed valve for removing residual pressure between the second shutoff valves, wherein the first shutoff valve, the second shutoff valve, the check valve and the bleed valve are integrated into one valve set through the integral body A non-return valve set of a gas purging system can be provided, characterized in that it is configured.

The integrated body includes an inert gas inlet for introducing the inert gas into the first flow path, an inert gas outlet for discharging the inert gas supplied to the first flow path, and a leaked gas discharged from the second flow path. A leaky gas outlet for discharging may be formed.

The non-return valve set may include a filter installed on the most upstream side on the first flow path to filter out foreign substances contained in the inert gas; and a pressure sensor installed on the first flow path between the filter and the first shut-off valve to measure the pressure of the inert gas at a corresponding point.

The first shut-off valve, the second shut-off valve and the bleed valve are provided as valves having an opening/closing function, wherein the first shut-off valve and the second shut-off valve operate so that the opening and closing states are always the same, and the bleed valve is The first shut-off valve and the second shut-off valve may operate so that an open/close state is always opposite to that of the first shut-off valve.

The check valve may be provided as a closeable type to enable blocking during maintenance.

The non-return valve set is a sub-check installed on the first flow path between the branching point of the first shut-off valve and the second flow path to allow the flow of the inert gas inside the first flow path to flow in only one direction. It may further include a valve;

The sub check valve may be provided as a closeable type to enable blocking during maintenance.

In addition, according to another aspect of the present invention for achieving the above object, in a ship having an engine using fuel gas, a purging line for supplying an inert gas to the engine for the purpose of purging the interior of the engine ; and a non-return valve set installed on the purging line to prevent a backflow of fuel gas from the engine, wherein the non-return valve set is sequentially installed from an upstream side of the purging line to the inside of the purging line. a first shut-off valve and a second shut-off valve for double opening or blocking the flow path; a check valve installed on the downstream side of the second shut-off valve on the purging line; And one valve set including; A ship's gas purging system can be provided, characterized in that it is configured.

A gas purging system for a ship according to another aspect of the present invention includes: an orifice installed on the downstream side of the non-return valve set on the purging line; and a differential pressure transmitter for measuring the front and rear pressure difference of the orifice, and when the differential pressure through the orifice is measured above a certain value, it is determined that a reverse flow occurs from the engine to the purging line side, It can generate an alarm and trip the engine or change the engine's fuel from fuel gas to fuel oil.

According to the present invention, as the design of the gas purging system is changed and applied so that the pipe from which the residual gas is discharged is not disposed in the engine room as much as possible during the purging process of the engine system using liquefied gas such as LNG as fuel, there is a risk of explosion In addition to maximizing the stability of the ship, it is possible to reduce the quantity of YARD, which has the effect of greatly improving the productivity in shipbuilding.

In addition, according to the present invention, by integrating the valves to be installed to prevent the reverse flow of LNG gas in the gas purging system into one valve set, the logic for the backflow prevention control is simplified, and accordingly, the inboard space utilization and There is an advantageous effect in terms of cost reduction.

In addition, the present invention can further secure additional stability in the operation of the engine system and the gas purging system by installing the orifice and the differential pressure gauge on the system for preventing the reverse flow of the LNG gas.

1 is a view schematically showing a gas purging system of a conventional ship.
2 is a view schematically showing a gas purging system of a ship according to the present invention.
3 is a piping diagram of a portion in which a non-return valve set is installed in a gas purging system of a ship according to the present invention.
4 is a more detailed view of the internal piping diagram of the non-return valve set according to the present invention.
5 is a view showing the appearance of a non-return valve set according to the present invention.
6 is a view of the non-return valve set shown in FIG. 5 as viewed from a downward direction.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described in the accompanying drawings.

The "liquefied gas" described in this specification is liquefied at a low temperature, such as LNG, LPG (Liquefied Petroleum Gas), LEG (Liquefied Ethane Gas), liquefied ethylene gas (Liquefied Ethylene Gas), liquefied propylene gas (Liquefied Propylene Gas), etc. It can contain all kinds of liquefied gas that can be stored and transported and can be supplied as fuel for an engine in a vaporized state. However, in the present specification, for convenience of explanation, LNG, which is a representative liquefied gas, will be described as an example.

In addition, in this specification, "ship" may be interpreted as a concept including all types of ships that can use liquefied gas as a fuel for a propulsion engine. Typical examples are LFS (LNG Fueled Ship), which is propelled by using LNG as a fuel, or LNGC (LNG Carrier), which uses LNG stored in a storage tank or boil-off gas generated from the storage tank as a fuel for an engine, and a ship that transports LNG. Examples include ships with self-propelled capabilities, as well as offshore structures floating in the sea, such as LNG Floating Production Storage Offloading (FPSO) and LNG FSRU (Floating Storage Regasification Unit).

Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

2 is a view schematically showing a gas purging system of a ship according to the present invention, and FIG. 3 is a piping diagram of a portion in which a non-return valve set is installed in the gas purging system of a ship according to the present invention.

Referring to FIG. 2 , the gas purging system of a ship according to the present invention includes an engine 100 using liquefied gas such as LNG as a fuel, and a gas for controlling the pressure and flow rate of fuel gas supplied to the engine 100 . A buffer tank (GVU: Gas Valve Unit) (210, 220) for supplying an inert gas for the purpose of purging the engine 100 and the inside of the line in which fuel gas is supplied to the engine 100 ( 300) is included.

In the present invention, the engine 100 may be an engine that can be driven by using LNG as a fuel, and thus a DF engine (Dual Fuel Engine) capable of using both heavy oil and natural gas as fuel is included therein.

In addition, in the present invention, the engine 100 includes a high-pressure gas injection engine 110 driven by supplying high-pressure compressed LNG gas, and a low-pressure gas injection engine 120 driven by receiving low-pressure compressed LNG gas. may include

The high-pressure gas injection engine 110 may be driven by supply of compressed and vaporized LNG gas to 10 bar or more, and may be, for example, a propulsion engine such as an ME-GI engine.

The low-pressure gas injection engine 120 may be driven by supplying compressed and vaporized LNG gas to less than 10 bar, for example, a general DF generator engine such as DFDG (Dual Fuel Diesel Generator) or X-DF (eXtreme Dual Fuel) and It may be the same propulsion engine.

The high-pressure gas injection engine 110 and the low-pressure gas injection engine 120 are disposed in an engine room partitioned on the stern side of the ship.

In addition, the ship of the present invention may be provided with an LNG storage tank (not shown) that stores LNG gas (natural gas) supplied to the engine 100 in a liquefied state, and the LNG stored in the LNG storage tank is stored in a fuel supply system ( FGSS: It may be compressed and vaporized in the Fuel Gas Supply System (400) and supplied as a fuel of the engine (100).

The fuel supply system 400 may include a vaporizer for forcibly vaporizing LNG and a compressor for compressing the LNG gas to the pressure required by the engine, and the like, and is typically a cargo compressor room (Cargo Compressor Room). ) is placed in

The LNG gas compressed and vaporized in the fuel supply system 400 may be supplied to the engine 100 along the fuel supply lines L1 and L2, and the high-pressure gas injection engine 110 and the low-pressure gas injection engine 120 are Since the required pressure and temperature are different, the first fuel supply line L1 connected to the high-pressure gas injection engine 110 and the second fuel supply line L2 connected to the low-pressure gas injection engine 120 are respectively It is provided as a separate line.

Specifically, the LNG gas compressed and vaporized at a high pressure in the fuel supply system 400 is supplied to the high-pressure gas injection engine 110 along the first fuel supply line L1, and the LNG gas compressed and vaporized at a low pressure is supplied to the second fuel supply line L1. 2 is supplied to the low-pressure gas injection engine 120 along the fuel supply line (L2).

In this way, LNG gas is supplied to the engines 110 and 120 through a pipe connected from the LNG storage tank to a ship using LNG as a fuel, and lines (L1, L2) for supplying the LNG gas to the engines 110 and 120 Gas valve units 210 and 220 are provided thereon.

The gas valve units 210 and 220 are equipment that group valves for controlling the pressure and flow rate of the LNG gas supplied to the engine 100, and are installed between the engine 100 and the LNG storage tank to supply the LNG gas to the engine ( 100) is supplied at a pressure corresponding to the load, and includes a filtration filter, a gas supply valve, and a gas flow meter.

In the present invention, the gas valve units 210 and 220 include a high-pressure gas valve unit 210 for controlling the LNG gas supplied to the high-pressure gas injection engine 110 and the LNG gas supplied to the low-pressure gas injection engine 120 . It may include a low pressure gas valve unit 220 to control.

The high-pressure gas valve unit 210 is installed on the first fuel supply line L1, and is typically disposed in the cargo compressor room as shown in the drawing, but low-pressure gas in the gas valve unit room (GVU Room) to be described later. It may be disposed together with the valve unit 220 .

The low pressure gas valve unit 220 is installed on the second fuel supply line L2 and may be disposed in the gas valve unit room. The gas valve unit room is located in a zone provided separately from the engine room, and may be disposed at the rear of the stern side of the engine room as shown in the drawing. It is of course also possible to arrange the low-pressure gas valve unit 220 together with the high-pressure gas valve unit 210 in the cargo compressor room.

The above-described cargo compressor room and gas valve unit room are spaces classified as gas hazardous zones, and since they are spaces for handling vaporized LNG gas, periodic ventilation must be performed for safety reasons. Be prepared for gas leaks by allowing air to be changed 30 times per hour. Therefore, an exhaust fan (f) may be provided in the cargo compressor room and the gas valve unit room to enable ventilation at all times.

On the other hand, a line leading to the high-pressure gas injection engine 110 from at least the cargo compressor room in the first fuel supply line L1 (from the gas valve unit room when the high-pressure gas valve unit 210 is provided in the gas valve unit room) Preferably, it is composed of a double pipe, and the inside of the double pipe may be configured to exchange air 30 times per hour.

Similarly, in the second fuel supply line (L2), at least the line from the gas valve unit room to the low-pressure gas injection engine 120 is preferably composed of a double pipe, and the inside of the double pipe can be configured to exchange air 30 times per hour. have.

The buffer tank 300 stores the engine 100 and the inert gas supplied to purify the inside of the fuel supply lines L1 and L2 through which the LNG gas is supplied to the engine 100 . As the inert gas, nitrogen (N ₂ ) is generally used, and in the following, nitrogen is used as an example to continue the description.

The ship of the present invention may be separately provided with a nitrogen generator (not shown) in order to use nitrogen as a purging gas, and the nitrogen generated from the nitrogen generator is temporarily stored in the buffer tank 300 and then the engine system. It may be supplied during purging.

The buffer tank 300 may be disposed in the engine room. The engine room is classified as a gas safe zone, and it is an area where safety from gas hazardous areas must be secured. For example, direct access from the gas hazardous area to the gas safe area is prohibited (if necessary, an air lock is installed), and the fuel supply pipe passing through the gas safe area must be completely enclosed by a double pipe or duct.

A purging line PL may be connected to supply nitrogen gas from the buffer tank 300 to the engine 100 side. The purging line PL may include a line connected from the buffer tank 300 to the high-pressure gas injection engine 110 and a line connected to the low-pressure gas injection engine 120 , respectively.

In addition, a non-return valve set 500 may be installed on the purging line PL to prevent reverse flow of the LNG gas inside the engine 100 toward the buffer tank 300 .

The non-return valve set 500 may be installed as one set per engine, or a main engine installed for propulsion of a ship and a generator engine installed to produce power required in the ship ) and only two can be installed.

The non-return valve set 500 may be disposed in a gas hazardous area where air is exchanged 30 times per hour, such as a gas valve unit room. However, the present invention is not limited thereto, and the non-return valve set 500 may be disposed in a cargo compressor room or other gas hazardous area. However, the non-return valve set 500 is preferably disposed as close as possible to the engine 100 and the buffer tank 300 in order to reduce the amount of water. Therefore, in the present invention, it can be seen that it is most preferable to arrange the non-return valve set 500 in the gas valve unit room as shown in the drawings.

The specific contents of the non-return valve set 500 will be dealt with in more detail later.

The nitrogen gas supplied from the buffer tank 300 for purging the engine system pushes the residual gas inside the engine 100, and the residual gas and nitrogen gas pushed out from the engine 100 are the gas valve units 210 and 220. It may be discharged to a safe area (eg, outside air) through the

A vent line VL for discharging residual gas and nitrogen gas discharged from the engine 100 to a safe area may be connected to the gas valve units 210 and 220, and a purging valve for opening and closing the line on the vent line VL (PV) can be installed respectively.

The purging operation of the high-pressure gas injection engine 110 and the low-pressure gas injection engine 120 side will be divided as follows.

When purging the high-pressure gas injection engine 110 side, first, the supply of LNG gas from the fuel supply system 400 to the high-pressure gas injection engine 110 side is stopped. And while supplying nitrogen gas from the buffer tank 300 into the high-pressure gas injection engine 110 , the purging valve PV on the vent line VL connected to the high-pressure gas valve unit 210 is opened. The residual gas pushed out from the high-pressure gas injection engine 110 by the nitrogen gas supplied from the buffer tank 300 passes through a part of the first fuel supply line L1 together with the nitrogen gas through the high-pressure gas valve unit 210. discharged to a safe area.

The purging of the low-pressure gas injection engine 120 side may be performed similarly. When purging the low-pressure gas injection engine 120 , first, the supply of LNG gas from the fuel supply system 400 to the low-pressure gas injection engine 120 is stopped. And while supplying nitrogen gas from the buffer tank 300 into the low pressure gas injection engine 120 , the purging valve PV on the vent line VL connected to the low pressure gas valve unit 220 is opened. The residual gas pushed out from the low-pressure gas injection engine 120 by the nitrogen gas supplied from the buffer tank 300 passes through a part of the second fuel supply line L2 together with the nitrogen gas through the low-pressure gas valve unit 220 . discharged to a safe area.

As described above, in the present invention, nitrogen gas is directly supplied to the engine 100 side, unlike the conventional injection of nitrogen gas onto the fuel supply line to purge the inside of the engine system, so that the residual gas inside the engine system is removed from the engine 100 . It is purged from the gas valve unit (210, 220) side.

That is, in the conventional (refer to FIG. 1), the purging of the engine system is performed in the order of the gas valve unit (4) → engine (1) → safe area, whereas in the present invention, purging of the engine system is performed by the engine 100 → gas valve unit (210, 220) → Safe Area.

In addition, in the present invention, a direction in which LNG gas is supplied as a fuel of the engine 100 and a direction in which the inside of the engine system is purged are reversed.

According to the present invention as described above, since nitrogen gas is directly injected into the engine 100 from the buffer tank 300 , and the residual gas inside the engine 100 is discharged through the gas valve units 210 and 220 , the engine room There is no need to provide a separate vent pipe inside, so there is an effect of reducing the amount of YARD compared to the prior art.

In addition, in the present invention, since most of the pipes from which residual gas is purged and discharged from the engine 100 are disposed in the gas valve unit room or cargo compressor room, the gas pipe disposed in the engine room can be greatly reduced, thereby maximizing stability. have. Since there are many electrical equipment, equipment handling oil, ignition equipment, etc. in the engine room, it is effective not to arrange the gas pipe in the engine room as much as possible as in the present invention. In addition, since the gas valve unit room (gas danger zone) is designed on the assumption that gas may leak, air exchange is always performed 30 times per hour. very advantageous In addition, when purging is performed from the engine 100 to the gas valve units 210 and 220 as in the present invention, the residual gas is already discharged through the fuel supply lines L1 and L2 composed of a double pipe, so the existing facility It is preferable in terms of cost because the utilization of the system is increased and there is no need to further provide a separate double pipe for discharging residual gas.

On the other hand, in ships such as LNGC or LFS, when a pipe for purging of the engine system is directly connected, a check valve is installed to prevent the fuel gas inside the engine system from flowing back to the nitrogen supply part, and In addition to this, the classification is demanding that a double block valve and a bleed valve be installed to enable remote control.

These requirements are already mandatory in the IGF CODE, and as the number of LFS ships is expected to increase in the future, these requirements will have to be mandatory.

However, such valves must be arranged in a gas hazardous area, and explosion-proof must be applied to prevent explosion, so they are quite expensive. Therefore, installing three expensive valves at each point where the point (the part where the purging pipe is directly connected) occurs is expected to have a significant impact on the shipbuilding price.

Therefore, the present invention has developed a concept comprising a double block valve, a bleed valve, and a check valve as one valve set. 500) will be described in detail.

Referring to FIG. 3 , the non-return valve set 500 according to the present invention is a first shut-off valve sequentially installed on the purging line PL for supplying nitrogen gas from the buffer tank 300 to the engine 100 side. 510 , a second shut-off valve 520 and a check valve 530 are included.

And the non-return valve set 500 according to the present invention is branched from the purging line PL between the first shut-off valve 510 and the second shut-off valve 520 and the leaking discharge line LL for discharging the leaked gas. ) and a bleed valve 540 installed on the leak discharge line LL may be further included.

The first shutoff valve 510 and the second shutoff valve 520 are valves for opening or blocking the internal flow path of the purging line PL, and may be provided as valves having an opening and closing function, such as a ball valve, for example. have.

The first shut-off valve 510 and the second shut-off valve 520 are sequentially installed on the upstream and downstream sides of the purging line PL, respectively, and are always opened or closed at the same time to double block or open the flow of nitrogen gas. do.

The first shut-off valve 510 and the second shut-off valve 520 are opened only when nitrogen gas is supplied from the buffer tank 300 to the engine 100 side, and are normally kept closed.

The check valve 530 is installed on the most downstream side of the purging line PL to prevent reverse flow of the LNG gas from the engine 100 side.

Although the check valve 530 is always in an open state, it functions to flow the fluid in only one direction, thereby first preventing the reverse flow of the LNG gas from the engine 100 side.

In the present invention, the check valve 530 may be provided as a closeable check valve to enable blocking during maintenance.

The bleed valve 540 is installed between the first shut-off valve 510 and the second shut-off valve 520 to reduce the residual pressure therein when the first shut-off valve 510 and the second shut-off valve 520 are blocked. serves to remove

The bleed valve 540 is normally open and discharges the leaked gas that has permeated between the first shut-off valve 510 and the second shut-off valve 520 to a safe area when a leak occurs in the second shut-off valve 520 . At this time, since the first shut-off valve 510 blocks the leaked gas again, it has the effect of double preventing the reverse flow from the engine 100 side.

The bleed valve 540 is blocked when the first shutoff valve 510 and the second shutoff valve 520 are opened. That is, the opening and closing operations of the first and second shutoff valves 510 and 520 and the bleed valve 540 are always reversed.

On the other hand, the non-return valve set 500 according to the present invention may further include an actuator for opening and closing the first and second shut-off valves 510 and 520 and the bleed valve 540, such an actuator. A tubing line TL for supplying compressed air (or hydraulic oil) for driving is connected, and a solenoid valve SV may be installed on the tubing line TL.

In the present invention, three actuators corresponding to each of the first shut-off valve 510, the second shut-off valve 520, and the bleed valve 540 requiring an opening/closing operation may be provided, or it is also possible to provide less than that.

In the present invention, since the operations of the first and second shut-off valves 510, 520 and the bleed valve 540 are always reversed, 2 using the characteristics of the valves 510, 520, 530 operating in a specific pattern One to three valves can be actuated at once by one actuator, and thus it is possible to provide fewer than three actuators.

Specifically, since the first and second shutoff valves 510 and 520 and the bleed valve 540 always operate in the opposite direction, the first and second shutoff valves 510 and 520 and the bleed valve 540 are one It can be configured so that it can be operated at once by connecting the actuator in the opposite direction only.

Alternatively, one actuator is connected to the first shut-off valve 510 and the second shut-off valve 520 and the bleed valve 540 are connected to another actuator, but using a mechanical link, the second The shut-off valve 520 and the bleed valve 540 may be configured in conjunction so that the operation is always reversed. At this time, of course, the first shut-off valve 510 and the bleed valve 540 may be bundled to be connected to one actuator instead of the second shut-off valve 520 .

As one or more actuators are provided as described above, one or more tubing lines TL for supplying a working fluid to each actuator are provided, and one or more solenoid valves SV are also provided to correspond to each tubing line TL. It may be, one or more solenoid valves (SV) bundled together may be referred to as a solenoid valve unit (Solenoid Valve Unit) (600).

At this time, in the case of the solenoid valve unit 600, an explosion-proof design is not necessary because it is not a line for handling gas. Not desirable.

Therefore, in the present invention, as shown in FIG. 2, the solenoid valve unit 600 is disposed in a gas safe zone inside the engine room at a position closest to the wall dividing the gas valve unit room, but the tubing Only the line TL is configured to extend through the gas valve unit room. According to such a configuration arrangement, it is possible to apply a general solenoid valve to which expensive explosion-proof equipment is not applied, which is advantageous in terms of cost.

In addition, the non-return valve set 500 according to the present invention has an orifice 710 installed on the downstream side of the check valve 530 on the purging line PL, and the front and rear pressure difference between the orifice 710 . may further include a differential pressure transmitter (DTP) 720 for measuring It is determined that the reverse flow to the line PL is generated, and an alarm is generated, the engine 100 is tripped, or the fuel of the engine 100 is replaced with fuel oil from fuel gas to achieve additional stability. .

4 is a more detailed view of the internal piping of the non-return valve set according to the present invention, FIG. 5 is a view showing the exterior of the non-return valve set according to the present invention, and FIG. 6 is the non-return valve shown in FIG. This is a view of the three from the bottom.

4 is a diagram showing the internal piping of the non-return valve set according to the present invention in more detail. A detailed description of the content already described in FIG. 3 shown to include only essential components will be omitted.

Referring to FIG. 4 , the non-return valve set 500 according to the present invention includes a first flow path 501 that provides a passage through which nitrogen gas is introduced and discharged, and a gas branched from the first flow path 501 and leaked. It may include a second flow path 502 for discharging.

As will be described later, the non-return valve set 500 according to the present invention is integrally configured in one body (B) as shown in FIG. 5 , so nitrogen gas and leak gas flow in the body (B). A flow path is formed.

Therefore, in this figure, the first flow path 501 can be understood as forming a part of the above-described purging line PL, and the second flow path 502 can be viewed as the same line as the above-described leak discharge line LL. . I hope that there is no confusion about the fact that the reference numbers in FIGS. 3 and 4 are differently assigned.

The non-return valve set 500 according to the present invention includes a filter 504 installed on the most upstream side on a first flow path 501 through which nitrogen gas flows, and between the filter 504 and the first shut-off valve 510 . Manual valve 505 and pressure sensor 506, which are sequentially installed in A check valve 531 may be further included.

The filter 504 filters foreign substances contained in the nitrogen gas flowing into the first flow path 501 , thereby preventing foreign substances from being caught in the valves installed later.

The manual valve 505 functions to physically block the first flow path 501 . The manual valve 505 is a valve that can be opened and closed manually, and is normally kept in an open state and can be shut off during maintenance.

The pressure sensor 506 is a sensor for measuring the pressure of nitrogen gas supplied to the first flow path 501 , and serves to determine whether nitrogen gas is well supplied during purging of the engine system.

The sub check valve 531 serves to once again prevent the LNG gas flowing back from the engine from leaking to the nitrogen supply side. In the present invention, the sub check valve 531 is not necessarily installed as a complementary configuration of the check valve 530 described above. Like the check valve 530 , the sub check valve 531 may be provided as a closeable type that can be blocked during maintenance.

Meanwhile, a gas block 507 may be connected to the outlet end of the first flow path 501 . The gas block 507 serves as a connection for connecting the first flow path 501 to a pipe requiring purging, and is a region where nitrogen gas and gas flowing backward from the engine can actually meet.

In the context shown in FIG. 4 , 'outer pipe' means a pipe for discharging the leaking gas discharged from the second flow path 502 to an external safe area.

5 and 6, in the non-return valve set 500 according to the present invention, the aforementioned valves 505, 510, 520, 530, 531, 540 and other components 504 and 506 are one It can be seen that it is integrated through the body (B) of That is, the non-return valve set 500 according to the present invention is manufactured as one set.

A pipe as shown in FIG. 4 may be formed inside the body (B) constituting one body, and valves (505, 510, 520, 540) for opening and closing the pipe formed inside the body (B) The valves 530 and 531 that are installed from the outside, and allow the fluid flowing through the inner pipe of the body B to flow only in one direction may be installed from the outside.

In addition, in the body B, a nitrogen gas inlet 503 for introducing nitrogen gas into the first flow path 501 (see FIG. 4 ) inside, and nitrogen gas introduced into the first flow path 501 (see FIG. 4 ) A nitrogen gas outlet 508 for discharging the , and a leaky gas outlet 509 through which the leaked gas is discharged through the internal second flow path 502 may be formed.

A purging line PL extending from the buffer tank 300 (see FIG. 2 ) may be connected to the nitrogen gas inlet 503 , and the above-described gas block 507 may be connected to the nitrogen gas outlet 508 . And the outer pipe shown in FIG. 4 may be connected to the leak gas outlet 509 .

As described above, according to the non-return valve set 500 of the present invention in which the first and second shut-off valves 510 and 520, the check valve 530 and the bleed valve 540 are integrated, the control for preventing backflow The simple control logic allows a compact configuration of the valve set, which not only has the expected effect of cost reduction, but also has the effect of increasing the use of space in the ship because it is easy to install in a narrow space.

In addition, if the system is configured to operate the valves 510, 520, 540, which require an opening/closing operation, by interlocking with less than three actuators, the number of cables and hydraulic oil supply lines will be reduced, and the above effect will be further maximized. can

On the other hand, the non-return valve set 500 proposed in the present invention is not limited to the application of the gas purging system of the present invention shown in FIG. Of course, it can be applied to any system directly connected, and also can be applied when nitrogen gas is injected into the fuel supply line as in the prior art. In addition, the non-return valve set 500 of the present invention is applicable not only to the gas purging system, but also to other gas handling systems that need to prevent backflow of fluid from occurring.

The present invention is not limited to the described embodiments, and it is apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, it should be said that such modifications or variations belong to the claims of the present invention.

100: engine
110: high-pressure gas injection engine
120: low pressure gas injection engine
210: high pressure gas valve unit
220: low pressure gas valve unit
300: buffer tank
400: fuel supply system
500: non-return valve set
B: body
501: 1st Euro
502: 2nd Euro
503: nitrogen gas inlet
504 : filter
505: manual valve
506: pressure sensor
507: gas block
508: nitrogen gas outlet
509: leak gas outlet
510: first shut-off valve
520: second shut-off valve
530: check valve
531: sub check valve
540: bleed valve
600: solenoid valve unit
L1: first fuel supply line
L2: 2nd fuel supply line
PL : Purging line
VL : bent line
PV : Purge valve
LL: Leakage discharge line
TL : Tubing line
SV : Solenoid valve

Claims (9)

In the non-return valve set of a gas purging system installed on a purging line for supplying an inert gas for the purpose of purging a gas pipe,
one-piece body;
a first flow path formed inside the integrated body and providing a passage through which the inert gas is introduced and discharged;
a second flow path branching from the first flow path and discharging the leaked gas;
a first shut-off valve and a second shut-off valve sequentially installed from an upstream side of the first flow path to double open or block the first flow path;
a check valve installed on the downstream side of the second shut-off valve on the first flow path to flow the inert gas in the first flow path in only one direction; and
It is installed on the second flow path branched from the first flow path between the first shut-off valve and the second shut-off valve, and when the first shut-off valve and the second shut-off valve are shut off, the first shut-off valve and the A bleed valve for removing the residual pressure between the second shut-off valves;
The first shut-off valve, the second shut-off valve, the check valve and the bleed valve are integrated into one valve set through the integrated body,
Non-return valve set for gas purging system. The method according to claim 1,
The integrated body includes an inert gas inlet for introducing the inert gas into the first flow path, an inert gas outlet for discharging the inert gas supplied to the first flow path, and a leaked gas discharged from the second flow path. Characterized in that a leaky gas outlet for discharging is formed,
Non-return valve set for gas purging system. 3. The method according to claim 2,
The non-return valve set is
a filter installed at the most upstream side on the first flow path to filter out foreign substances contained in the inert gas; and
Further comprising; a pressure sensor installed on the first flow path between the filter and the first shut-off valve to measure the pressure of the inert gas at the corresponding point;
Non-return valve set for gas purging system. 3. The method according to claim 2,
The first shut-off valve, the second shut-off valve and the bleed valve are provided as valves having an opening/closing function,
The first shut-off valve and the second shut-off valve operate so that an open/close state is always the same,
The bleed valve is characterized in that the opening and closing state of the first shut-off valve and the second shut-off valve are always opposite to each other,
Non-return valve set for gas purging system. 5. The method according to claim 4,
The check valve is characterized in that it is provided in a closeable type (Closable Type) to enable blocking during maintenance,
Non-return valve set for gas purging system. 6. The method of claim 5,
The non-return valve set is
Further comprising; a sub check valve installed on the first flow path between the branching point of the first shut-off valve and the second flow path to allow the flow of the inert gas inside the first flow path to flow in only one direction;
Non-return valve set for gas purging system. 7. The method of claim 6,
The sub check valve is characterized in that it is provided in a closeable type (Closable Type) to enable blocking during maintenance,
Non-return valve set for gas purging system. In a ship equipped with an engine using fuel gas,
a purging line for supplying an inert gas to the engine for the purpose of purging the interior of the engine; and
and a non-return valve set installed on the purging line to prevent the fuel gas from flowing back from the engine,
The non-return valve set is
a first shut-off valve and a second shut-off valve sequentially installed from the upstream side of the purging line to double open or block the internal flow path of the purging line;
a check valve installed on the downstream side of the second shut-off valve on the purging line; and
A bleed valve branched from the purging line between the first shut-off valve and the second shut-off valve and installed on the leaking discharge line for discharging the gas leaked from the second shut-off valve; including a single valve set characterized by being
Ship's gas purging system. 9. The method of claim 8,
an orifice installed on the downstream side of the non-return valve set on the purging line; and
Further comprising a differential pressure transmitter (Differential Pressure Transmitter) for measuring the pressure difference before and after the orifice,
When the differential pressure through the orifice is measured above a certain value, it is determined that a reverse flow from the engine to the purging line is generated, and an alarm is generated and the engine is tripped or the fuel of the engine is converted from fuel gas to fuel oil. characterized by replacing
Ship's gas purging system.

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