WO2023136033A1 - Power cable for submersible pump, pump carry-in method, and pump pull-up method - Google Patents

Abstract

The present invention relates to a power cable for supplying power to a submersible pump for raising the pressure of a liquefied gas such as liquefied ammonia, liquefied natural gas (LNG), or liquid hydrogen. The present invention further relates to: a method for carrying a submersible pump into a pump column by using such a power cable; and to a method for pulling up the submersible pump from the pump column. A power cable (36) is for supplying power to a submersible pump (2) disposed inside a pump column (3) in order to transfer liquefied gas, the power cable comprising: a plurality of split power cables (36A); and a plurality of cable connectors (36B) electrically connecting the plurality of split power cables (36A).

Description

Power cable for submerged pump, pump loading method, pump lifting method

The present invention relates to a power cable for supplying power to submerged pumps that boost the pressure of liquefied gases such as liquefied ammonia, liquefied natural gas (LNG), and liquid hydrogen. Further, the invention relates to a method of loading a submersible pump into a pump column and a method of lifting a submersible pump out of the pump column using such a power cable.

Natural gas is widely used for thermal power generation and as a chemical raw material. Further, ammonia and hydrogen are expected as energy that does not generate carbon dioxide that causes global warming. Applications of hydrogen for energy include fuel cells and turbine power generation. Since natural gas, ammonia and hydrogen are gaseous at normal temperatures, natural gas, ammonia and hydrogen are cooled and liquefied for their storage and transportation. Liquefied gas such as liquefied natural gas (LNG), liquefied ammonia, and liquefied hydrogen is temporarily stored in a liquefied gas storage tank and then transferred to a power plant, factory, or the like by a pump.

FIG. 19 is a schematic diagram showing a conventional example of a liquefied gas storage tank in which liquefied gas is stored and a pump for pumping up the liquefied gas. The pump 500 is installed in a vertical pump column 505 installed in the liquefied gas reservoir 501 . An upper end opening of the pump column 505 is closed with an upper lid 510 . The inside of the pump column 505 is filled with liquefied gas, and the entire pump 500 is immersed in the liquefied gas. Pump 500 is thus a submerged pump that can operate in liquefied gas. When the pump 500 is operated, the liquefied gas in the liquefied gas reservoir 501 is drawn into the pump column 505, ascends the pump column 505, and is discharged from the pump column 505 through the liquefied gas discharge port 509.

The pump 500 is housed in a pump column 505 with a suspension cable 508 connected to its upper portion. The upper portion of the suspension cable 508 is wound around a cable holding portion 511 extending from the upper lid 510 into the pump column 505 and held by the cable holding portion 511 . The lower end of suspension cable 508 is connected to pump 500 . Accordingly, suspension cable 508 is also accommodated within pump column 505, similar to pump 500. FIG.

The hanging cable 508 is used when the pump 500 is carried into the pump column 505 and when the pump 500 is pulled up from the pump column 505. By leaving the suspension cable 508 connected to the pump 500, the work of connecting the suspension cable 508 to the pump 500 when the pump 500 is lifted is eliminated. During operation of pump 500 , suspension cable 508 is immersed in liquefied gas within pump column 505 with pump 500 .

A power cable 507 is similarly connected to the motor of the pump 500 and extends through the pump column 505 to the outside of the pump column 505 . Power is supplied to the electric motor of pump 500 through power cable 507 so that pump 500 can operate within pump column 505 .

20A and 20B are diagrams for explaining the operation of carrying the pump 500 into the pump column 505 and the operation of pulling the pump 500 up from the pump column 505. FIG. When the pump 500 is installed in the pump column 505 and when the pump 500 is lifted from the pump column 505 for maintenance or the like, the upper end of the suspension cable 508 is connected to the hoist 513 . Pump 500 is suspended on suspension cable 508 and is raised and lowered within pump column 505 by hoist 513 .

As the pump 500 ascends and descends, the power cable 507 is also drawn out into the pump column 505 and pulled up from the pump column 505 .

Japanese Patent No. 3197645 Japanese Patent No. 3198248 Japanese Patent No. 3472379

However, the pump column 505 for liquefied gas is generally very long in the vertical direction, and may extend to several tens of meters. The power cable 507 connected to the pump 500 installed at the bottom of such a pump column 505 is also necessarily long. As a result, the work of feeding the power cable 507 into the pump column 505 and the work of pulling it up from the pump column 505 are very large-scale. In particular, when the power cable 507 is pulled up from the pump column 505, the power cable 507 in contact with the liquefied gas is very cold, and handling of the long power cable 507 is dangerous.

Therefore, the present invention provides a power cable that can facilitate the handling of the power cable connected to the submersible pump, ensures the safety of workers, and reduces the burden on workers. offer. The invention also provides a method of loading a submersible pump into the pump column and a method of lifting the submersible pump from the pump column using such a power cable.

In one aspect, a power cable for powering a submersible pump positioned within a pump column for transporting liquefied gas, comprising: a plurality of split power cables; A power cable is provided that includes a plurality of cable connectors that physically connect.

In one aspect, the length of each split power cable is shorter than the length of said pump column.
In one aspect, each cable connector comprises a female connector and a male connector connected to opposite ends of each split power cable.
In one aspect, the plurality of cable connectors are each supported by a plurality of connecting links connecting a plurality of split suspension cables for suspending the submersible pump within the pump column.
In one aspect, the load of the plurality of split power cables is supported by the plurality of split suspension cables.

In one aspect, a method of loading a submersible pump used to transfer liquefied gas into a pump column, wherein a sling cable connected to a winch moves the submersible pump into the pump column. A method is provided for connecting a plurality of split power cables for powering the submersible pump one by one with cable connectors while lowering the submersible pump.

In one aspect, the method further includes housing the submersible pump within a purge vessel, supplying a purge gas into the purge vessel, and exposing the submersible pump to the purge gas.
In one aspect, the step of lowering the submersible pump within the pump column by the lifting cable connected to the hoisting machine includes connecting a plurality of divided lifting cables one by one with a connecting link while the lifting cable is connected to the hoisting cable. lowering the submerged pump in the pump column by means of the plurality of split suspension cables connected to the machine;
In one aspect, the cable connector is supported by the connecting link.
In one aspect, the load of the plurality of split power cables is supported by the plurality of split suspension cables.

In one aspect, a method of hoisting a submersible pump used to transfer liquefied gas from a pump column, wherein the submersible pump is hoisted within the pump column by a sling cable connected to a hoist. Meanwhile, a method is provided for removing, one by one, a plurality of split power cables for powering the submersible pump.

In one aspect, the method further includes moving the submersible pump from the pump column into a purge vessel, supplying a purge gas into the purge vessel, and exposing the submersible pump to the purge gas.
In one aspect, the step of pulling up the submersible pump within the pump column by the suspension cable connected to the hoist includes dividing a plurality of divided suspension cables that constitute the suspension cable connected to the hoist. It is a step of lifting the submersible pump in the pump column by the suspension cable while removing them one by one.
In one aspect, the plurality of split power cables are electrically connected by cable connectors, the plurality of split suspension cables are connected by connecting links, and the cable connectors are supported by the connecting links. ing.
In one aspect, the load of the plurality of split power cables is supported by the plurality of split suspension cables.

According to the present invention, since a plurality of split power cables are used, the submersible pump can be carried into the pump column while adding these split power cables one by one. Further, the submersible pump can be lifted from the pump column while removing the multiple split power cables one by one. Workers do not need to handle long power cables (for example, several tens of meters), so the burden on workers can be reduced. In particular, worker safety is ensured when pulling the cryogenic power cable out of the pump column.

1 illustrates one embodiment of a pump system for transporting liquefied gas; FIG. Figure 2A is a side view of one embodiment of a connecting link. FIG. 2B is a top view of the connecting link. FIG. 4 is a side view showing a connecting link, a split hanging cable connected to the connecting link, and a split power cable attached to the connecting link; FIG. 4 is a diagram showing a state in which two split hanging cables are connected to a connecting link, and two split power cables are connected by a male connector and a female connector; FIG. 11 is a top view showing another embodiment of a connecting link; FIG. 10 is a cross-sectional view of one embodiment of a head plate and sealing link; FIG. 10 illustrates one embodiment of the pump system prior to loading the submersible pump into the pump column and the lifting device used to load the submersible pump into the pump column. FIG. 11 is a perspective view showing one embodiment of a locking member; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 11 illustrates one embodiment of a method of loading a submersible pump into a pump column; FIG. 10 illustrates one embodiment of a method of lifting a submersible pump from a pump column; FIG. 10 illustrates one embodiment of a method of lifting a submersible pump from a pump column; FIG. 10 illustrates one embodiment of a method of lifting a submersible pump from a pump column; FIG. 10 illustrates one embodiment of a method of lifting a submersible pump from a pump column; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a conventional example of a liquefied gas storage tank in which liquefied gas is stored and a pump for pumping up the liquefied gas. FIG. 4 is a diagram for explaining the work of loading the pump into the pump column and the work of pulling the pump up from the pump column;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 illustrates one embodiment of a pump system for transporting liquefied gas. Examples of liquefied gases that may be transported by the pump system shown in FIG. 1 include liquefied ammonia, liquid hydrogen, liquid nitrogen, liquefied natural gas, liquefied ethylene gas, liquefied petroleum gas, and the like.

As shown in FIG. 1, the pump system includes a submerged pump 2 for transferring liquefied gas, a pump column 3 in which the submerged pump 2 is housed, and a A purge container 1, a cover wall 10 fixed to the upper end of the purge container 1, and an upper lid 12 closing an upper opening of the cover wall 10 are provided. The pump column 3 is installed in a liquefied gas storage tank 5 in which liquefied gas is stored. The pump column 3 is a vertically extending hollow container, the upper part of which protrudes upward from the liquefied gas storage tank 5 . A purge container 1 communicates with a pump column 3 . The pump column 3 has a purge gas introduction port 8 and a discharge port 9 .

A suction valve 6 is provided at the bottom of the pump column 3 . The submerged pump 2 is installed on the suction valve 6 of the pump column 3 . The suction valve 6 has a valve body 6A that covers the lower opening of the pump column 3, and a plurality of springs 6B that bias the valve body 6A upward. When the submerged pump 2 is not placed on the valve body 6A, the valve body 6A is pressed against the lower end of the pump column 3 by a plurality of springs 6B to close the lower opening of the pump column 3. When the submerged pump 2 is placed on the valve body 6A, the self-weight of the submerged pump 2 causes the valve body 6A to move downward against the force of the spring 6B, thereby opening the suction valve 6. As shown in FIG. The intake valve 6 may be an actuator-driven valve (eg, an electrically operated valve).

The purge container 1 is a device for exposing the submerged pump 2 to purge gas before the submerged pump 2 is carried into the pump column 3 and after the submerged pump 2 is pulled up from the pump column 3 . A purge container 1 is fixed to the upper end of the pump column 3 . The purge container 1 has a purge gas inlet port 17 and a gas outlet port 18 communicating with its internal space 15 . An upper opening of the purge container 1 is covered with a head plate 20 and a lower opening of the purge container 1 can be closed by a gate valve 21 . The gate valve 21 of the present embodiment is of a manual type that is opened and closed by manually operating the handle 21a, but may be configured to be electrically opened and closed.

The head plate 20 is detachably fixed to the upper end of the purge container 1. Suspension cables 23 and connecting structures 28 are suspended from sealing links 30 fixed to head plate 20 . Suspension cables 23 include a plurality of split suspension cables 23B and connection links 24 that connect these split suspension cables 23B. The length of each divided suspension cable 23B is shorter than the length of the pump column 3. A plurality of divided hanging cables 23B are connected in series by connecting links 24 .

The connection structure 28 is attached to the submerged pump 2 . The connection structure 28 has a connection link 33 at its upper end, and this connection link 33 is connected to the lower end of the suspension cable 23 . A specific configuration of the connecting structure 28 is not particularly limited, and it may include a cable, a rod, or the like. Suspension cables 23 and connecting structures 28 extend vertically through purge vessel 1 and pump column 3 .

The head plate 20 is covered by the cover wall 10 and the upper lid 12. An electrical terminal 35 is attached to the upper surface of the upper lid 12 . This electrical terminal 35 is connected to a power supply (not shown). A power cable 36 for supplying power to the electric motor of the submersible pump 2 extends vertically along the suspension cable 23 and the coupling structure 28 through the pump column 3, the purge vessel 1 and the cover wall 10 to provide electrical power. It is electrically connected to terminal 35 . The power cable 36 includes a plurality of split power cables 36A and cable connectors 36B electrically connecting the split power cables 36A. The length of each split power cable 36A is shorter than the length of the pump column 3. A plurality of divided power cables 36A are connected in series by cable connectors 36B.

During operation of the submerged pump 2, the purge gas introduction port 8, the purge gas inlet port 17, and the gas outlet port 18 are closed by valves (not shown), and the gate valve 21 is opened.

During operation of the submerged pump 2, the liquefied gas in the liquefied gas storage tank 5 is introduced into the pump column 3 through the suction valve 6, and the pump column 3 is filled with the liquefied gas. During operation of the submerged pump 2, the entire submerged pump 2 is immersed in the liquefied gas. Therefore, the submerged pump 2 is configured to be operable in liquefied gas. The liquefied gas pressurized by the submerged pump 2 is transferred to the outside through the discharge port 9 .

FIG. 2A is a side view showing one embodiment of a connecting link 24 for connecting a plurality of split hanging cables 23B, and FIG. 2B is a top view of the connecting link 24. FIG. The connecting link 24 has two pin holes 24a into which connecting pins (to be described later) for connecting the split hanging cables 23B are inserted. These pin holes 24 a are located at the upper and lower portions of the connecting link 24 . The connecting link 24 has a flange portion 25 projecting sideways. The connecting link 24 has a cable passage 26 vertically passing through the flange portion 25 . A split power cable 36 A is inserted into this cable passage 26 . In this embodiment, the cable passage 26 has an outwardly open notch shape so that the split power cable 36A can be inserted into the cable passage 26 from the side of the connecting link 24 . In other embodiments, cable passageway 26 may have the shape of a through hole.

FIG. 3 is a side view showing the connecting link 24, the divided suspension cable 23B connected to the connecting link 24, and the divided power cable 36A supported by the connecting link 24. FIG. Each split suspension cable 23B has a connecting terminal 29 at its end, and this connecting terminal 29 has a through hole 29a through which the connecting pin 31 can pass. The connecting pin 31 is inserted into the through hole 29a of the connecting terminal 29 of each divided suspension cable 23B and the pin hole 24a of the connecting link 24, whereby each divided suspension cable 23B is connected to the connecting link 24. As shown in FIG.

The split power cables 36A are electrically connected by a cable connector 36B including a female connector 37 and a male connector 38. The male connector 38 has a shape that fits inside the female connector 37 . A female connector 37 is connected to the upper end of each split power cable 36A, and a male connector 38 is connected to the lower end of each split power cable 36A. The split power cable 36A has a width smaller than the cable passage 26, but the female connector 37 has a width greater than the width of the cable passage 26, and the female connector 37 passes through the cable passage 26. can't. Therefore, the female connector 37 also functions as a stopper that prevents the split power cable 36A from falling from the connecting link 24. As shown in FIG. In other words, split power cable 36A is supported by connecting link 24 via female connector 37 . Therefore, the load of the split power cable 36A connected to the female connector 37 is supported by the split suspension cable 23B connected to the connecting link 24. FIG.

If the male connector 38 has a width greater than the width of the cable passage 26, the male connector 38 may be connected to the upper end of the split power cable 36A and the female connector 37 may be connected to the lower end of the split power cable 36A. . In this case, the male connector 38 functions as a stopper that prevents the split power cable 36A from falling from the connecting link 24. FIG.

FIG. 4 is a diagram showing a state in which two divided hanging cables 23B are connected to the connecting link 24 and two divided power cables 36A are connected by the male connector 38 and the female connector 37. FIG. As shown in FIG. 4, the male connector 38 and the female connector 37 are connected by inserting the male connector 38 connected to the upper divided power cable 36A into the female connector 37 connected to the lower divided power cable 36A. This establishes an electrical connection between the upper split power cable 36A and the lower split power cable 36A. Male connector 38 and female connector 37 are supported by connecting link 24 . Furthermore, since the connecting link 24 can support the load of the lower split power cable 36A, unintended disconnection of the male connector 38 and the female connector 37 can be prevented.

Each split power cable 36A may be split into three split power cables for three-phase AC. In that case, as shown in FIG. 5, each connecting link 24 may have three cable passages 26 into which three split power cables for three-phase alternating current are inserted.

FIG. 6 is a cross-sectional view showing one embodiment of the head plate 20 and sealing link 30. FIG. The head plate 20 includes a plate body 40 shaped to cover the upper opening of the purge container 1, a projection 41 extending upward from the plate body 40, a movable flange 42 surrounding the projection 41, and the projection 41. A seal 44 (for example, gland packing) is provided to seal the gap between the outer surface and the inner surface of the movable flange 42 . The projecting portion 41 and the movable flange 42 have a cylindrical shape. The movable flange 42 is vertically movable relative to the projecting portion 41 and the plate body 40 . The head plate 20 has cable ports 47 fixed to both sides of the plate body 40 . Each cable port 47 has a hole (not shown) through which the hanging cable 23 can pass.

The head plate 20 has a through hole 50 formed in the projecting portion 41 . The through hole 50 extends vertically. The width of the through-hole 50 is larger than the width of the upper portion of the suspension cable 23 and the connection structure 28 (see FIG. 1), and the upper portion of the connection structure 28 (including the connection link 33) and the suspension cable 23 (including the connection link 24). ) can pass through the through hole 50 . The head plate 20 is removably secured to the upper end of the purge vessel 1 by fasteners 53 such as bolts and nuts. The sealing link 30 is removably fixed to the movable flange 42 by fasteners (not shown) such as screws. The upper end of through hole 50 is closed by sealing link 30 . A power cable 36 extends through the sealing link 30 . The split suspension cable 23B and the power cable 36 that constitute the suspension cable 23 extend through the through hole 50 .

Next, an embodiment of a method for carrying the submerged pump 2 into the pump column 3 will be described. FIG. 7 shows an embodiment of the pump system before loading the submersible pump 2 into the pump column 3 and the lifting device 60 used to load the submersible pump 2 into the pump column 3. It is a diagram. The cover wall 10 and the top lid 12 are removed before the submersible pump 2 is carried into the pump column 3 . Gate valve 21 is closed.

The lifting device 60 includes a hoist 61 such as a hoist or a winch, the suspension cable 23 connected to the hoist 61 , the connection structure 28 extending upward from the submerged pump 2 , and the submerged pump 2 . The head plate 20 is arranged above and has a shape that covers the upper opening of the purge container 1 , and a locking member 65 that locks the connecting structure 28 to the head plate 20 . A hoist 61 is arranged above the pump column 3 and the purge container 1 .

The lower end of the connecting structure 28 is connected to the submerged pump 2, and the upper end of the connecting structure 28 is composed of a connecting link 33. Since this connecting link 33 has the same configuration as the connecting link 24 described with reference to FIGS. 2 to 4 or 5, redundant description thereof will be omitted.

The connecting link 33 has a laterally projecting flange portion 33a. The locking member 65 is engaged with the flange portion 33 a of the connecting link 33 . The split power cable 36A extends through a cable passage (not shown) formed in the flange portion 33a of the connecting link 33, and the female connector 37 connected to the upper end of the split power cable 36A extends through the flange portion 33a. locked to. A cable passage (not shown) of the connecting link 33 has the same structure as the cable passage 26 of the connecting link 24 described with reference to FIGS. 2 to 5, so redundant description thereof will be omitted.

The connecting link 33 extends through the locking member 65 and is supported by the locking member 65 . A locking member 65 is placed on the head plate 20 . More specifically, the locking member 65 is arranged so as to partially cover the through hole 50 of the head plate 20 . Coupling structure 28 and split power cable 36 A extend through through hole 50 .

FIG. 8 is a perspective view showing one embodiment of the locking member 65. FIG. In this embodiment, locking member 65 is shaped to engage connecting links 24, 33 (see FIG. 1). The locking member 65 of this embodiment has an opening 66 in its center and is divided into a plurality of members 65A, 65A. The opening 66 has a size that does not allow passage of the connecting links 24, 33 (see FIG. 1).

In this embodiment, the locking member 65 that functions as a stopper for the connecting links 24 and 33 is a split ring (for example, a split ring) made up of a plurality of (typically two) members. However, the configurations of the connecting links 24, 33 and the locking member 65 are not limited to this embodiment as long as they can perform their intended functions. For example, locking member 65 may be a single member (eg, a U-shaped member) having a notch extending outwardly from its center. Further, the connecting links 24, 33 may be structures such as shackles. In another example, the connecting links 24 and 33 have through holes extending in the horizontal direction instead of having protrusions extending in the lateral direction, and the locking member 65 is a rod-like member inserted into the through holes. good too.

Returning to FIG. 7, the width of the locking member 65 is larger than the width of the through hole 50 of the head plate 20, and the locking member 65 cannot pass through the through hole 50. On the other hand, the width of the connecting link 33 is smaller than the width of the through hole 50 of the head plate 20 so that the connecting link 33 can pass through the through hole 50 . However, as long as the connecting link 33 is supported by the locking member 65 , the connecting link 33 cannot pass through the through hole 50 . The submersible pump 2 is thus suspended from the locking member 65 on the head plate 20 by the connecting structure 28 including the connecting link 33 . The load of the submerged pump 2 is supported by the head plate 20 via the connecting structure 28 including the connecting link 33 and the locking member 65 . The split power cable 36A extends along the connecting structure 28 and the female connector 37 connected to the split power cable 36A is supported on the connecting link 33. As shown in FIG.

Before the submerged pump 2 is carried into the purge container 1, the purge gas inlet port 17 is connected to the purge gas supply line 71 extending from the purge gas supply source 70, and the gas outlet port 18 is connected to the vacuum line 74. be. Vacuum line 74 is connected to a vacuum source (not shown) such as a vacuum pump. Examples of purge gas sources 70 include nitrogen gas sources, helium gas sources, hydrogen gas sources, or combinations thereof. In one embodiment, the purge gas source 70 may include multiple purge gas sources of different types, such as at least two of a nitrogen gas source and a helium gas source and a hydrogen gas source. In this case, multiple purge gas supply sources may be selectively connected to the purge gas supply line 71 .

9 to 14 are diagrams explaining an embodiment of a method for carrying the submerged pump 2 into the pump column 3. FIG. A series of operations shown in FIGS. 9 to 14 includes a dry-up operation in which the submerged pump 2 is exposed to the purge gas in the purge container 1, an operation in which the submerged pump 2 is lowered in the pump column 3, and a plurality of divided suspensions. It includes an operation of splicing the cables 23B to the suspension cable 23 one by one, and an operation of splicing the plurality of divided power cables 36A to the power cable 36 one by one.

Liquefied gas is discharged from the pump column 3 before the loading operation described below. Specifically, the purge gas is supplied into the pump column 3 from the purge gas supply line 71 and/or the purge gas introduction port 8 , and the pressure of the purge gas discharges the liquefied gas from the pump column 3 through the suction valve 6 .

At step 101 , the suspension cable 23 connected to the hoist 61 is connected to the head plate 20 . More specifically, the suspension cable 23 connects to the cable port 47 of the headplate 20 . The submerged pump 2 is suspended from the head plate 20 by a connecting structure 28 including a connecting link 33 and a locking member 65 . One of the plurality of split power cables 36A is connected to the electric motor of the submerged pump 2, and the female connector 37 at the upper end of the split power cable 36A is engaged with the connecting link 33.

In step 102, the submersion pump 2, the head plate 20, the connection structure 28, the split power cable 36A, and the locking member 65 are all lowered by the hoist 61, and the top of the purge container 1 is lifted by the head plate 20. cover the opening. The head plate 20 is secured to the upper end of the purge container 1 by fasteners 53 shown in FIG.

At step 103 , the hoisting cable (first hoisting cable) 23 A connected to the hoist 61 is disconnected from the cable port 47 . Furthermore, one of a plurality of split hanging cables (second hanging cables) 23B prepared in advance is added to the hanging cable 23 . More specifically, the upper end of the newly added divided suspension cable 23B is connected to the suspension cable 23A connected to the hoist 61 via the connection link 24, and the newly added divided suspension cable 23B The lower end is connected to the connecting link 33 of the connecting structure 28 . In this embodiment, the suspension cable 23 includes a first suspension cable 23A extending from the hoist 61 and a plurality of split suspension cables (second suspension cables) 23B that can be separated from the first suspension cable 23A.

Similarly, one of a plurality of divided power cables 36A prepared in advance is added to the power cable 36. More specifically, the newly added split power cable 36A is passed through the cable passage 26 (see FIG. 2) of the connecting link 24, and the female connector 37 attached to the split power cable 36A is connected to the connecting link 24. place on top. Further, the male connector 38 attached to the newly added divided power cable 36A is connected to the female connector 37 on the already installed divided power cable 36A. As a result, the newly added split power cable 36A is electrically connected to the existing split power cable 36A. A plurality of divided power cables 36A electrically connected in this manner constitute a power cable 36. FIG.

With the upper opening of the purge container 1 covered with a head plate 20 and the lower opening of the purge container 1 closed with a gate valve 21, the internal space 15 of the purge container 1 containing the submerged pump 2 is filled with gas. A vacuum is drawn through outlet port 18 . Thereafter, a purge gas (including, for example, an inert gas and/or a gas having the same composition as that of the liquefied gas) is supplied through the purge gas inlet port 17 into the interior space 15 to fill the interior space 15 with the purge gas. The submersible pump 2 is exposed (contacted) to purge gas within the purge vessel 1 , thereby excluding air and moisture from the surfaces of the submersible pump 2 . This step is a dry-up that expels air and moisture from the submersible pump 2 . The evacuation of the internal space 15 and the supply of the purge gas to the internal space 15 may be repeated.

The purge gas used is a gas composed of a component with a boiling point lower than the boiling point of the liquefied gas to be pumped by the submerged pump 2. This is to prevent the purge gas from liquefying when it contacts the liquefied gas. Examples of purge gas include inert gases such as nitrogen gas and helium gas. For example, when the liquefied gas to be pumped by the submerged pump 2 is liquefied natural gas, nitrogen gas, which is a gas composed of nitrogen having a boiling point (−196° C.) lower than the boiling point (−162° C.) of liquefied natural gas. is used for the purge gas. In another example, when the liquefied gas to be pumped by the submersible pump 2 is liquid hydrogen, helium gas, which is a gas made of helium having a boiling point (-269°C) lower than the boiling point of hydrogen (-253°C). is used for the purge gas.

A part of the purge gas may be gas composed of the same components as those of the liquefied gas. If the gas outlet port 18 is connected to a gas processor, all of the purge gas may be gas of the same composition as the liquefied gas. For example, if the liquefied gas is liquid hydrogen, some or all of the purge gas may be hydrogen gas. Alternatively, if the liquefied gas is liquefied ammonia, some or all of the purge gas may be ammonia gas.

In step 104 , the hoisting device 61 lifts the suspension cable 23 , the split power cable 36A and the submerged pump 2 slightly, and removes the locking member 65 from the head plate 20 . The load of the submerged pump 2 is supported by the hoist 61 . In order to prevent the inflow of air from the through hole 50 of the head plate 20, the supply of the purge gas into the purge container 1 through the purge gas inlet port 17 is continued. Meanwhile, the evacuation of the internal space 15 of the purge container 1 through the gas outlet port 18 is stopped. Furthermore, the gate valve 21 is opened.

In step 105, the hoist 61 further lowers the suspension cable 23, the split power cable 36A, the connection structure 28, and the submerged pump 2. While the submerged pump 2 is being lowered, purge gas may be supplied into the pump column 3 from the purge gas introduction port 8 . Before the uppermost connecting link 24 enters the purge container 1 , the locking member 65 is again placed on the head plate 20 . When the submersible pump 2 is lowered, the split suspension cable 23B and the split power cable 36A extend through the through hole 50 of the head plate 20. As shown in FIG.

In step 106, the suspension cable 23, the split power cable 36A, the coupling structure 28, and the latent cable 24 are connected until the connection link 24 connected to the upper end of the split suspension cable 23B engages (contacts) the locking member 65. The submerged pump 2 is lowered by the hoist 61. - 特許庁When the connecting link 24 engages the locking member 65 , the load of the submerged pump 2 is supported by the locking member 65 and the head plate 20 .

Then, until the submerged pump 2 approaches the bottom of the pump column 3, the same steps as the steps 103 to 106 are performed while adding (connecting) the remaining divided suspension cables 23B one by one, and This is repeated while connecting the rest of the plurality of divided power cables 36A one by one with the cable connectors 36B. The load of a plurality of divided power cables 36A connected by a cable connector 36B including a female connector 37 and a male connector 38 is supported by a plurality of divided hanging cables 23B via connecting links 24. FIG. While the submerged pump 2 is being lowered, purge gas is fed into the pump column 3 through the purge gas inlet port 17 and/or the purge gas introduction port 8 .

In step 107, when the submerged pump 2 approaches the bottom of the pump column 3, the last split suspension cable 23B is added to the suspension cables 23 and the last split power cable 36A is added to the power cable 36. The sealing link 30 described with reference to FIG. 6 is connected to the upper end of the last split suspension cable 23B. A male connector 38 is connected to the lower end of the split power cable 36A, and the upper part of the split power cable 36A extends through the sealing link 30. As shown in FIG.
At step 108 , the locking member 65 is removed from the head plate 20 and then the submersible pump 2 is lowered until the sealing link 30 reaches a position directly above the head plate 20 . The submerged pump 2 is arranged at a predetermined position directly above the intake valve 6 within the pump column 3 .
In step 109, the movable flange 42 of the head plate 20 is lifted upward and fixed to the sealing link 30 by fasteners (not shown) such as screws.

At step 110 , seal link 30 , movable flange 42 and submerged pump 2 are lowered until seal link 30 contacts head plate 20 . The submersible pump 2 is placed on the intake valve 6 . The suction valve 6 is opened by the self-weight of the submerged pump 2 .
At step 111, the suspension cable 23A is disconnected from the sealing link 30, after which the cover wall 10 is fixed to the upper end of the purge vessel 1. FIG. The uppermost split power cable 36 A is connected to an electrical terminal 35 installed on the upper surface of the top cover 12 , and the top cover 12 is further fixed to the cover wall 10 .

According to this embodiment, since a plurality of split power cables 36A are used, the submerged pump 2 can be carried into the pump column 3 while adding (connecting) these split power cables 36A one by one. can. Workers do not need to handle long power cables (for example, several tens of meters), so the burden on workers can be reduced.

Furthermore, in the present embodiment, since a plurality of split suspension cables 23B are used, the submerged pump 2 can be carried into the pump column 3 while adding (connecting) these split suspension cables 23B one by one. . Workers do not need to handle long suspension cables (for example, several tens of meters), so the burden on workers can be reduced.

Next, an embodiment of a method for pulling up the submerged pump 2 from the pump column 3 will be described with reference to FIGS. 15 to 18. FIG. In pulling up the submerged pump 2, basically, the steps described with reference to FIGS. 9 to 14 are performed in the reverse order. A series of operations shown in FIGS. 15 to 18 includes an operation to raise the submerged pump 2 within the pump column 3, an operation to remove the plurality of split suspension cables 23B one by one, and one operation to pull the plurality of split power cables 36A. It includes a step-by-step removal operation and a hot-up where the submersible pump 2 is exposed to purge gas within the purge vessel 1 .

In step 201, the top lid 12 is removed from the cover wall 10 and the uppermost split power cable 36A is disconnected from the electrical terminals 35. Furthermore, the cover wall 10 is removed from the purge container 1 . The suspension cable 23A is then connected to the sealing link 30, whereby the suspension cable 23A is connected via the sealing link 30 to the suspension cable 23B extending from the connecting structure 28 connected to the submersible pump 2. be. The hoist 61 lifts the sealing link 30, the movable flange 42, the suspension cable 23B, the split power cable 36A, the connection structure 28, and the submerged pump 2 slightly, and the suction valve 6 is closed. Further, purge gas is supplied into the purge container 1 and the pump column 3 through the purge gas inlet port 17 . The pressure in the pump column 3 increases and the suction valve 6 opens accordingly. Liquefied gas is thereby discharged from the pump column 3 through the intake valve 6 .

At step 202, the movable flange 42 is separated from the sealing link 30. Further, the plurality of divided suspension cables 23B, the plurality of divided power cables 36A, and the connection are continued until the entire uppermost divided suspension cable 23B and the entire uppermost divided power cable 36A are positioned above the purge container 1. The structure 28 and submerged pump 2 are pulled up by the hoist 61 . After that, the locking member 65 is placed on the head plate 20 . The suspension cable 23B and the split power cable 36A extend through the through hole 50 of the head plate 20 when the submersible pump 2 is raised.

In step 203, the split suspension cable 23B, split power cable 36A, connecting structure 28, and submerged pump 2 are moved until the connecting link 24 directly above the locking member 65 engages (contacts) with the locking member 65. It is slightly lowered by the hoist 61.例文帳に追加The load of submerged pump 2 is supported by locking member 65 and head plate 20 .

At step 204 , the uppermost split hanging cable 23 B outside the purge container 1 is removed from the hanging cable 23 . The sealing link 30 is removed from the suspension cable 23 together with the split suspension cable 23B. The uppermost split power cable 36 A is also removed from the power cable 36 . At this time, the male connector 38 connected to the lower end of the split power cable 36A is disconnected from the female connector 37 on the connecting link 24 supported by the locking member 65. As shown in FIG.

At step 205 , the suspension cable 23 A extending from the hoist 61 is connected to the connecting link 24 engaged with the locking member 65 . As a result, the suspension cable 23A is reconnected to the submerged pump 2 via the split suspension cable 23B.
Then, the steps similar to Step 202 to Step 205 are repeated until the submerged pump 2 is lifted into the purge container 1 by the hoist 61 while removing (separating) the plurality of divided hanging cables 23B one by one. and while removing (disconnecting) the plurality of divided power cables 36A one by one. While the submersible pump 2 is being raised, purge gas is fed into the pump column 3 through the purge gas inlet port 17 and/or the purge gas introduction port 8 .

At step 206 , the gate valve 21 is closed while the submerged pump 2 is positioned inside the purge container 1 . With the top opening of the purge container 1 covered with a head plate 20 and the bottom opening of the purge container 1 closed with a gate valve 21, a purge gas (e.g. inert gas and/or the same component as the liquefied gas) is injected. ) is supplied to the interior space 15 through the purge gas inlet port 17 to fill the interior space 15 with the purge gas. The submerged pump 2 is exposed (contacted) to the purge gas in the purge container 1, thereby warming the submerged pump 2. As shown in FIG. This step is a hot-up for heating the submerged pump 2 .

In step 207, fasteners 53 (see FIG. 6) such as bolts and nuts fixing the head plate 20 to the purge container 1 are removed. After that, the suspension cable 23A is connected to the cable port 47 of the head plate 20. As shown in FIG. Then, the hoist 61 lifts the head plate 20, the connecting structure 28, the lowermost divided power cable 36A, the locking member 65, and the submersible pump 2 together to purge the submersible pump 2. Move out of container 1.

According to this embodiment, since a plurality of split power cables 36A are used, the submersible pump 2 can be pulled up from the pump column 3 while removing (separating) these split power cables 36A one by one. Workers do not need to handle long power cables (for example, several tens of meters), so the burden on workers can be reduced. In particular, the safety of the operator when pulling up the cryogenic power cable 36 from the pump column 3 can be ensured.

Further, according to the present embodiment, since a plurality of divided suspension cables 23B are used, the submerged pump 2 is pulled up from the pump column 3 while removing (separating) these divided suspension cables 23B one by one. can be done. Workers do not need to handle long suspension cables (for example, several tens of meters), so the burden on workers can be reduced. In particular, it is possible to ensure the safety of workers when pulling up the cryogenic hanging cable 23 from the pump column 3 .

The above-described embodiments are described for the purpose of enabling those who have ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiments can be made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the present invention is not limited to the described embodiments, but is to be construed in its broadest scope in accordance with the technical spirit defined by the claims.

The present invention can be used as a power cable for supplying power to submerged pumps that boost the pressure of liquefied gases such as liquefied ammonia, liquefied natural gas (LNG), and liquid hydrogen. Further, the present invention is applicable to a method of loading a submersible pump into a pump column and a method of lifting a submersible pump from the pump column using such a power cable.

1 purge container 2 submerged pump 3 pump column 5 liquefied gas storage tank 6 suction valve 8 purge gas introduction port 9 discharge port 10 cover wall 12 upper lid 15 internal space 17 purge gas inlet port 18 gas outlet port 20 head plate 21 gate valve 23 suspension Cable 23A First hanging cable 23B Divided hanging cable (second hanging cable)
24 connecting link 24a pin hole 25 flange portion 26 cable passage 28 connecting structure 29 connecting terminal 30 sealing link 31 connecting pin 33 connecting link 33a flange portion 35 electrical terminal 36 power cable 36A split power cable 36B cable connector 37 female connector 38 male Connector 40 Plate body 41 Protrusion 42 Movable flange 44 Seal 47 Cable port 50 Through hole 53 Fastener 60 Lifting device 61 Hoist 65 Locking member 66 Opening 70 Purge gas supply source 71 Purge gas supply line 74 Vacuum line

Claims (15)

1. A power cable for powering a submersible pump positioned within a pump column for transporting liquefied gas, comprising:
   a plurality of split power cables;
   A power cable comprising a plurality of cable connectors electrically connecting the plurality of split power cables.
2. The power cable according to claim 1, wherein the length of each split power cable is shorter than the length of the pump column.
3. The power cable according to claim 1 or 2, wherein each cable connector comprises a female connector and a male connector connected to both ends of each split power cable.
4. 4. The plurality of cable connectors according to any one of claims 1 to 3, wherein the plurality of cable connectors are respectively supported by a plurality of connection links that connect a plurality of split suspension cables for suspending the submerged pump in the pump column. power cable as described in section.
5. The power cable according to claim 4, wherein the load of the plurality of split power cables is supported by the plurality of split suspension cables.
6. A method of loading a submersible pump used to transfer liquefied gas into a pump column, comprising:
   While the submersible pump is lowered in the pump column by a suspension cable connected to a hoist, a plurality of split power cables for supplying power to the submersible pump are connected one by one by cable connectors. how to.
7. housing the submerged pump in a purge container;
   7. The method of claim 6, further comprising supplying a purge gas into the purge vessel and exposing the submersible pump to the purge gas.
8. The step of lowering the submerged pump in the pump column by the suspension cable connected to the hoist includes connecting a plurality of divided suspension cables one by one with a connection link to the hoist. 8. A method according to claim 6 or 7, wherein said submersible pump is lowered within said pump column by means of said plurality of split suspension cables.
9. The method of claim 8, wherein said cable connector is supported by said connecting link.
10. The method according to claim 9, wherein the loads of the plurality of split power cables are supported by the plurality of split suspension cables.
11. A method of raising a submersible pump used to transfer liquefied gas from a pump column, comprising:
    A method of removing, one by one, a plurality of split power cables for powering the submersible pump while the submersible pump is being hoisted within the pump column by a sling cable connected to a hoist.
12. moving the submerged pump from the pump column into a purge vessel;
    12. The method of claim 11, further comprising supplying a purge gas into the purge vessel and exposing the submersible pump to the purge gas.
13. The step of pulling up the submerged pump in the pump column by the suspension cable connected to the hoist includes removing, one by one, a plurality of divided suspension cables constituting the suspension cable connected to the hoist. 13. A method according to claim 11 or 12, wherein the suspension cable raises the submersible pump within the pump column.
14. The plurality of split power cables are electrically connected by cable connectors,
    The plurality of divided hanging cables are connected by connecting links,
    14. The method of claim 13, wherein said cable connector is supported by said connecting link.
15. The method according to claim 14, wherein the load of said plurality of split power cables is supported by said plurality of split suspension cables.

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