JP6924810B2 - A device that airtightly seals a movable shaft, and a compressor or expander device that uses such a device. - Google Patents

Description

The present invention relates to a device for sealing a movable shaft.

Specifically, the present invention is an expander device including, but not limited to, at least one expander element having a drive shaft for driving a driven shaft of a mechanical load such as a generator. Therefore, a power transmission device provided with a cabinet is provided between the driven shaft and the drive shaft, and the driven shaft and the drive shaft extend into the cabinet, which is intended for application in an expander device.

The power transmission device can be, for example, a gear type power transmission device, a belt type power transmission device, a direct coupling, or a flexible coupling.

During expansion, the generator can generate electrical energy.

Such expander devices are known to be used for the expansion of natural gas.

It is known that during the operation of the expander device, some of the natural gas to be expanded leaks into the cabinet via the drive shaft of the expander element, despite the shaft seal being provided.

In other words, the presence of natural gas in the cabinet causes a slight overpressure, which ensures that the outside air cannot leak into the cabinet and mixes the natural gas with air in the cabinet. Make it avoidable.

In practice, this natural gas is expelled to the outlet side of the expander device as needed to avoid excessive pressure in the cabinet.

If the emitted natural gas contains air, these can cause problems and further shut down the system.

On the generator side as well, specifically near the drive shaft, there is also a leak between the cabinet and the generator / environment.

The drive shaft of the generator must be tightly sealed, as natural gas leaks from the cabinet not only can result in loss of overpressure in the cabinet, but is also disadvantageous if air enters the cabinet. ..

However, this is not possible with known seals. There are always a few leak paths.

As a result, there is always the risk of excess natural gas leaking out and the pressure inside the cabinet becoming too low and / or air getting into the cabinet.

An object of the present invention is to provide a solution to at least one of the above and other disadvantages by providing a device that allows for an airtight seal of the movable shaft.

An object of the present invention is a device for airtightly sealing a movable shaft, which comprises a movable shaft and two seals attached around the movable shaft at a certain distance from each other, and between the seals around the movable shaft. In addition, a liquid chamber filled with liquid and closed on both sides by a seal is located, and the liquid chamber is directly connected to the liquid column, so that the liquid column guarantees the hydrostatic pressure in the liquid chamber. ..

The "movable shaft" means a shaft that performs a motion such as a rotational motion or a translational motion at the time of operation.

"Direct connection" means that the liquid has a free path from the liquid chamber to the liquid column, there are no closures or valves, in other words, the liquid chamber and the liquid column form one liquid volume. means.

This allows overpressure with respect to the pressure on the opposite side of the seal by forming a liquid chamber that provides high hydrostatic pressure, which allows gas from one side to the other side of the liquid chamber via a movable shaft. The advantage is that it cannot leak.

The height of the liquid column can be suitably selected so that sufficient hydrostatic pressure is always present in the liquid chamber.

The liquid column can be realized, for example, by a liquid-filled pipe or conduit that is connected to the liquid chamber and can extend vertically upward in the liquid chamber to generate hydrostatic pressure under normal conditions.

However, as is well known, the hydrostatic pressure produced depends only on the height or level of the liquid in the liquid column, not on the exact shape of the liquid column.

Therefore, here, it is necessary to interpret "liquid column" in a broad sense regarding the shape of "column".

Another advantage is that such a device does not include moving or expensive parts and is therefore an inexpensive and sustainable solution for airtight sealing of movable shafts.

Yet another advantage is that this device can be provided for many different types of machines.

The distance between the two seals around the movable shaft is selected depending on the machine of interest. For example, in an expander device that expands natural gas, this distance can be 5 millimeters.

The seal prevents liquid from leaking out of the liquid chamber. Such seals are known to be much more effective at sealing liquid leaks than gas leaks.

Moreover, the problems caused by leaks of liquids such as water or oil are far less than those caused by leaks of natural gas.

The device preferably further comprises a tank that is at least partially filled with the liquid and a water supply pipe that extends from the tank to the liquid inlet of the liquid chamber.

In this way, the liquid chamber can be replenished from the tank. Since the liquid column is directly connected to the liquid chamber, the hydrostatic pressure in the liquid chamber is increased by replenishing the liquid column in this way.

In other words, this allows the pressure in the liquid chamber to be controlled.

Of course, it is also possible to collaborate with a liquid column that can be replenished, for example at the top.

In a preferred embodiment, the liquid column uses a conduit or pipe, one end of which is connected to the liquid chamber and the other end of which is connected to the tank.

This has the advantage of forming a completely closed liquid circuit consisting of a liquid chamber, a liquid column, a tank and a water supply pipe.

The present invention is a compressor device including at least one compressor element having a driven shaft driven by a drive shaft of a drive unit, and a power transmission device including a cabinet between the driven shaft and the drive shaft. The driven shaft and the drive shaft extend into the cabinet, two seals are attached around the drive shaft at a distance from each other, and the seals around the drive shaft are filled with liquid and sealed. It also relates to a compressor device in which a liquid chamber closed on both sides is located and the liquid chamber is directly connected to the liquid column so that the liquid column guarantees hydrostatic pressure in the liquid chamber.

The present invention is an expander device comprising at least one expander element having a drive shaft that drives a mechanically loaded driven shaft, the power having a cabinet between the driven shaft and the drive shaft. A transmission device is provided, the driven shaft and the drive shaft extend into the cabinet, two seals are attached around the driven shaft at a distance of a certain distance from each other, and a liquid is placed between the seals around the driven shaft. It also relates to an expander device in which a liquid chamber is located that is filled and closed on both sides by a seal, and the liquid chamber is directly connected to the liquid column so that the liquid column guarantees hydrostatic pressure in the liquid chamber.

The mechanical load can be, for example, a generator, compressor element, or pump element.

Needless to say, the advantages of such a compressor and expander device are similar to those of the device for hermetically sealing the movable shaft according to the present invention.

Hereinafter, for the purpose of better showing the features of the present invention, some preferred embodiments of the device according to the present invention for hermetically sealing the movable shaft to which the application is applied and the compressor or expander device will be described with reference to the accompanying drawings. It will be described as an example without any limiting properties.

It is a figure which shows typically the device which performs the airtight seal of a movable shaft by this invention. It is a figure which shows schematicly the expander apparatus by this invention. It is a figure which shows schematicly the compressor apparatus by this invention.

The device 1 for airtightly sealing the movable shaft 2 according to the present invention, which is schematically shown in FIG. 1, includes two seals 3 attached around the shaft 2.

In this example, although not essential for the present invention, the seal 3 is a lip seal.

The seals 3 are attached around the shaft 2 at a distance A from each other so that a space can be freely maintained between the seals.

A liquid chamber 4 is located between the seals 3 around the shaft 2. The liquid chamber 4 is closed on both sides by the seal 3, or in other words, the seal 3 is a part of the wall portion of the liquid chamber 4.

The liquid chamber can be realized, for example, by providing in the housing 5 the necessary recesses 6 or grooves to which the shaft 2 is movably mounted.

The liquid chamber 4 is filled with the liquid 7.

In this example, the liquid 7 is oil, but the present invention is not limited thereto.

The seal 3 prevents the liquid 7 from leaking out of the liquid chamber 4 via the movable shaft 2.

The device 1 according to the present invention also includes a liquid column 8.

The liquid column 8 is directly connected to the liquid chamber 4.

The liquid column 8 can provide hydrostatic pressure in the liquid chamber 4.

As mentioned above, this means that the liquid 7 is free to flow from the liquid chamber 4 to the liquid column 8 and that the valve or other closure does not obstruct the flow path of the liquid 7.

In this example, the device 1 further comprises a tank 9 that is at least partially filled with the liquid 7 and a water supply pipe 10 that extends from the tank 9 to the inlet 11 of the liquid 7 in the liquid chamber 4.

The water supply pipe 10 includes a liquid pump 12 capable of pumping the liquid 7 from the tank 9 to the liquid chamber 4.

The liquid pump 12 may have its own drive unit, or may be driven by the movable shaft 2 as in this example. Alternatively, in other words, the movable shaft 2 is a part of the drive unit of the liquid pump 12.

The inlet 11 of the liquid 7 of the liquid chamber 4 prevents the liquid 7 from leaving the liquid chamber 4 through the inlet 11 while allowing the liquid 7 to flow back into the liquid chamber 4 through the check valve 13 in the reverse direction. It can be closed by the check valve 13.

This prevents the liquid chamber 4 from becoming empty when the liquid pump 12 is stopped.

It is not excluded that the inlet 11 is closed by using a different type of valve instead of the check valve 13.

In the illustrated example, a conduit 14 is used in the liquid column 8 in which one end 15a is connected to the liquid chamber 4 and the other end 15b is connected to the tank 9.

The conduit 14 can also be a pipe or a tube.

Under normal operating conditions of the device 1, it is clear that the conduit 14 extends vertically above the liquid chamber 4.

The position where the conduit 14 intersects the tank 9 is higher than that of the liquid chamber 4 in FIG.

Further, in this example, by extending the movable shaft 2 into the tank 9, the device 1 according to the present invention can prevent any gas existing in the tank 9 from leaking along the movable shaft 2.

Here, this tank can be used as a cabinet for a power transmission device as described in the following examples of embodiments.

The operation of the device 1 is very simple and is as follows.

During operation, that is, when the movable shaft 2 is rotating, the liquid pump 12 is driven by the movable shaft 2.

The liquid 7 is pumped from the tank 9 to the liquid chamber 4 via the water supply pipe 10 to the inlet 11 of the liquid chamber 4.

Since the liquid column 8 is connected to the liquid chamber 4, the water level in the liquid column 8 rises as a result.

If the water level continues to rise, the excess liquid 7 will eventually overflow into the tank 9, which can be pumped back from the tank 9 to the liquid chamber 4.

Due to the liquid column 8, there is a hydrostatic pressure in the liquid chamber 4 that is higher than the pressure in the tank 9.

This high hydrostatic pressure can be guaranteed by making the liquid column 8 sufficiently high.

This prevents the gas contained in the tank 9 from leaking beyond the liquid chamber 4.

As a result, the leakage of gas from the tank 9 is prevented, and the maintenance of the pressure in the tank 9 is guaranteed.

When the movable shaft 2 stops, the liquid pump 12 also stops. As a result, the liquid 7 is no longer pumped into the liquid chamber 4.

The check valve 13 prevents the liquid 7 from flowing out of the liquid chamber 4, thereby maintaining the water level of the liquid column 8 and thus the pressure in the liquid chamber 4.

As a result, gas cannot leak from the tank 9 even after the movable shaft 2 has stopped.

In other words, the device 1 ensures an airtight seal on the shaft 2 even if the movable shaft 2 is not moving.

FIG. 2 shows an expander device 16 provided with the device 1 according to the present invention as shown in FIG.

In this example, the expander device 16 includes one expander element 17, which can also be a plurality of expander elements 17.

The expander element 17 includes a drive shaft 18 that drives a driven shaft 19 of a mechanical load 20 which is a generator 20 in this example.

Therefore, the generator 20 should serve as a mechanical load 20. However, the present invention is not limited to this. The mechanical load 20 can also be a compressor element or a pump element.

A power transmission device 21 exists between the drive shaft 18 and the driven shaft 19, and the tank 9 serves as a cabinet 22 of the casing 22 or the housing 22.

In this example, the power transmission device 21 is executed as a gear type power transmission device 21, and the cabinet 22 is a gearbox 22, but the present invention is not limited thereto.

Both the drive shaft 18 and the driven shaft 19 extend into the gearbox 22.

In this example, the movable shaft 2 is the driven shaft 19 of the generator 20. That is, two seals 3 are provided around the driven shaft 19 so as to be separated from each other by a distance A, and a liquid chamber 4 having a liquid column 8 is provided around the middle of the driven shaft 19.

In other respects, the configuration of the device 1 provided with the expander device 16 is similar to FIG.

The operation of the device 1 provided with the expander device 16 is similar to that of FIG.

FIG. 3 is very similar to FIG. 2, except that in this example it is a diagram relating to a compressor device 23 that includes a compressor element 24 and a drive unit 25 instead of the expander element 17 and the generator 20.

The drive unit 25 can be, for example, an electric motor.

The device 1 according to the present invention as shown in FIG. 1 is provided on the drive shaft 18 of the drive unit 25.

In other respects, this device is similar to FIG.

In the above example, the shaft is always movable, specifically the rotating shaft 2, but it is clear that the present invention can also be applied to the movable translating shafts 2.

Of course, the present invention is also applicable to non-movable shafts or stationary shafts, but another device for hermetically sealing such shafts is already known.

The present invention is by no means limited to the embodiments described as an example and shown in the drawings, and the device according to the present invention for hermetically sealing the movable shaft to which the application is applied and the compressor or expander device is within the scope of the present invention. It can be realized in all kinds of forms and dimensions without deviation.

1 Device 2 Movable shaft 3 Seal 4 Liquid chamber 5 Housing 6 Recess 7 Liquid 8 Liquid column 9 Tank 10 Water supply pipe 11 Inlet 12 Liquid pump 13 Check valve 14 Conduit 15a One end of conduit 15b The other end of conduit A Distance between seals

Claims (25)

A device (1) for airtightly sealing the movable shaft (2), the movable shaft (2) and two seals (2) attached around the movable shaft (2) at a distance (A) from each other. A liquid chamber (4) is located between the seals (3) around the movable shaft (2), the liquid chamber (4) filled with the liquid (7) and closed on both sides by the seal (3). By directly connecting the liquid chamber (4) to the liquid column (8), the liquid column (8) guarantees the hydrostatic pressure in the liquid chamber (4), and the device (1) A tank (9) at least partially filled with the liquid (7) and a water supply pipe (10) extending from the tank (9) to the inlet (11) of the liquid (7) in the liquid chamber (4). The tank (9) serves as a cabinet (22) of the power transmission device (21).
A device characterized by that. The water supply pipe (10) includes a liquid pump (12) configured to pump the liquid (7) from the tank (9) to the liquid chamber (4).
The device according to claim 1. The movable shaft (2) is a part of a drive unit of the liquid pump (12).
The device according to claim 2. The liquid column (8), one end (15a) of the connected conduits (14) or pipes the liquid chamber (4) to be connected the other end (15b) of the tank (9) is used,
The device according to any one of claims 1 to 3. The movable shaft (2) extends into the tank (9).
The device according to any one of claims 1 to 4. The inlet (11) of the liquid (7) can be closed by a check valve (13) that prevents the liquid (7) from leaving the liquid chamber (4) through the inlet.
The device according to any one of claims 1 to 5. The liquid (7) is an oil.
The device according to any one of claims 1 to 6. The seal (3) is a lip seal.
The device according to any one of claims 1 to 7. A compressor device including at least one compressor element (24) having a driven shaft (19) driven by a drive shaft (18) of a drive unit, wherein the driven shaft (19) and the drive shaft (18) are provided. ), A power transmission device (21) provided with a cabinet (22) is provided, and the driven shaft (19) and the drive shaft (18) extend into the cabinet (22), and the driven shaft (19) extends into the cabinet (22). Two seals (3) are attached around the drive shaft (19) at a distance (A) from each other, and a liquid (7) is provided between the seals (3) around the driven shaft (19). A liquid chamber (4) that is filled and closed on both sides by the seal (3) is located, and the liquid chamber (4) is directly connected to the liquid column (8) so that the liquid column (8) becomes the said. It comes to guarantee the hydrostatic pressure in the liquid chamber (4),
A compressor device characterized by that. The cabinet (22) is at least partially filled with the liquid (7) and is provided with a water supply pipe (10) extending from the cabinet (22) to the inlet (11) of the liquid (7) in the liquid chamber (4). Be,
The compressor device according to claim 9. The water supply pipe (10) includes a liquid pump (12) capable of pumping a liquid (7) from the cabinet (22) to the liquid chamber (4).
The compressor device according to claim 10. The liquid pump (12) is driven by the drive shaft (18).
The compressor device according to claim 11. The liquid column (8), one end (15a) of the connected conduits (14) or pipes are connected to the liquid chamber (4) to the other end (15b) of the cabinet (22) is used,
The compressor device according to any one of claims 10 to 12. The inlet (11) of the liquid (7) can be closed by a check valve (13) that prevents the liquid (7) from leaving the liquid chamber (4) through the inlet (11).
The compressor device according to any one of claims 10 to 13. The liquid (7) is an oil.
The compressor device according to any one of claims 9 to 14. The seal (3) is a lip seal.
The compressor device according to any one of claims 9 to 15. An expander device including at least one expander element (17) having a drive shaft (18) for driving a driven shaft (19) of a mechanical load (20), the same as the driven shaft (19). A power transmission device (21) provided with a cabinet (22) is provided between the drive shaft (18) and the driven shaft (19) and the drive shaft (18) in the cabinet (22). Two seals (3) are attached around the driven shaft (19) at a distance (A) from each other, and between the seals (3) around the driven shaft (19). A liquid chamber (4) filled with the liquid (7) and closed on both sides by the seal (3) is located, and the liquid chamber (4) is directly connected to the liquid column (8) to form the liquid column. (8) guarantees the hydrostatic pressure in the liquid chamber (4).
A featured expander device. The cabinet (22) is at least partially filled with the liquid ( 7 ) and is provided with a water supply pipe (10) extending from the cabinet (22) to the inlet (11) of the liquid (7) in the liquid chamber (4). Be,
The expander device according to claim 17. The water supply pipe (10) includes a liquid pump (12) capable of pumping a liquid (7) from the cabinet (22) to the liquid chamber (4).
The expander device according to claim 18. The liquid pump (12) is driven by the driven shaft (19).
The expander device according to claim 19. The liquid column (8), one end (15a) of the connected conduits (14) or pipes are connected to the liquid chamber (4) to the other end (15b) of the cabinet (22) is used,
The expander device according to any one of claims 18 to 20. The inlet (11) of the liquid (7) can be closed by a check valve (13) that prevents the liquid (7) from leaving the liquid chamber (4) through the inlet (11).
The expander device according to any one of claims 18 to 21. The liquid (7) is an oil.
The expander device according to any one of claims 17 to 22. The seal (3) is a lip seal.
The expander device according to any one of claims 17 to 23. The mechanical load (20) is a generator, compressor element, or pump element.
The expander device according to any one of claims 17 to 23.

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