Container and pump system

Abstract

Hollow containers (3, 4) are provided above a hollow column (2) provided around a liquefied gas pump (P), and a cable (8) for installing and removing the liquefied gas pump (P) is passed through the center of the containers (3, 4) from the bottom towards the top. The containers (3, 4) include: lower plate members (5, 6) having, at the center, cable through-holes (9, 10) allowing the cable (8) to pass; and stuffing box members (12) provided around the cable through-holes (9, 10) at the center of the lower plate members (5, 6), and having, at the center, cable insertion holes (13) through which the cable (8) is inserted. The stuffing box members (12) include opening diameter adjustment mechanisms (14, 20) that adjust the sizes of the opening diameters of the cable insertion holes (13).

Description

Container and Pump System

[0001] The present invention relates to a container and a pump system.

[0002] Among liquefied gas pumps, conventional liquefied natural gas (LNG) pumps have dealt with the risk of LNG leaking to the outside by placing a temporary plate on the flange at the top of the column (see, for example, Patent Document 1). Because LNG is heavier than air in low-temperature regions, it is not released into the atmosphere. On the other hand, in the case of cryogenic fluids such as liquefied hydrogen and liquefied ammonia, the specific gravity of the gasified gas is lighter than air, so there is a risk of liquefied hydrogen or liquefied ammonia being released.

[0003] When performing maintenance on a liquefied hydrogen pump, the boiling point of liquefied hydrogen is -253°C, while air (mainly oxygen and nitrogen) liquefies and freezes at temperatures in the -253°C range. When air liquefies, liquid oxygen is produced, which poses a risk of explosion, and when air freezes, both nitrogen and oxygen pose a risk of damaging the pump. Furthermore, when performing maintenance on a liquefied ammonia pump, ammonia is toxic if it leaks outside, which could pose a health hazard to people.

[0004] During maintenance of a liquefied gas pump, when a cryogenic pump is being pulled up, or when a cryogenic pump is being installed, in order to prevent air from entering or the liquid (liquefied hydrogen, liquefied ammonia, etc.) from being released to the outside, a partitioned chamber such as a buffer container that is installed on the column around the liquefied gas pump and forms a barrier zone, or a purge container that is installed on the buffer container, is required.

[0005] The bulkhead room is equipped with a door to separate the interior from the atmosphere side or the tank side, but because the cable (wire) used to install and remove the liquefied gas pump passes through the interior of the bulkhead room, there was a problem of gas leaking through the cable pass-through hole.

[0006] In the case of a liquid hydrogen pump, it is not possible to fully prevent nitrogen and oxygen from entering the column, and in the case of an ammonia pump, ammonia gas leaks out to the top and outside. Furthermore, because the cable diameter is not uniform and requires fittings such as shackles and links, the hole in the door must be larger than the cable diameter. As described above, it has traditionally been extremely difficult to prevent gas leakage through cable pass-through holes.

[0007] JP 2018-80801 A

[0008] The present invention has been made under the above-mentioned circumstances, and an object of the present invention is to provide a container and a pump system that can prevent gas from leaking from a cable pass-through hole.

[0009] One aspect of the present invention is a container, which is a hollow container provided above a hollow column provided around a liquefied gas pump, and a cable for installing and extracting the liquefied gas pump passes through the center of the container from the bottom to the top of the container, and the container comprises: a lower plate member provided at the bottom of the container, and having a cable through hole in the center through which the cable can pass; and a stuffing box member provided in the center of the lower plate member around the cable through hole, and having a cable insertion hole in the center through which the cable is inserted, and the stuffing box member is provided with an opening diameter adjustment mechanism that adjusts the size of the opening diameter of the cable insertion hole.

[0010] Another aspect of the present invention is a pump system, which includes a liquefied gas pump and the container described above.

[0011] As will be described below, there are other aspects of the present invention, and therefore, this disclosure is intended to provide some aspects of the present invention and is not intended to limit the scope of the invention as described and claimed herein.

[0012] FIG. 1 is an explanatory diagram (side view) showing a pump system according to an embodiment of the present invention. FIG. 2 is an explanatory diagram (perspective view) showing a pump system according to an embodiment of the present invention. FIG. 3 is an explanatory diagram (side view) showing a stuffing box according to an embodiment of the present invention. FIG. 4 is an explanatory diagram (side view) showing a stuffing box according to an embodiment of the present invention. FIG. 5 is an explanatory diagram (plan view) showing a stuffing box according to an embodiment of the present invention. FIG. 6 is an explanatory diagram (plan view) showing a stuffing box according to an embodiment of the present invention. FIG. 7 is an explanatory diagram (side view) showing the inflow of purge gas according to an embodiment of the present invention. FIG. 8 is an explanatory diagram (side view) showing a stuffing box according to another embodiment. FIG. 9 is an explanatory diagram (side view) showing a stuffing box according to another embodiment. FIG. 10 is an explanatory diagram (plan view) showing a stuffing box according to another embodiment. FIG. 11 is an explanatory diagram (plan view) showing a stuffing box according to another embodiment. FIG. 12 is an explanatory diagram (side view) showing a pump system according to another embodiment. FIG. 13 is an explanatory diagram (perspective view) showing a pump system according to another embodiment.

[0013] DETAILED DESCRIPTION OF THE INVENTION The present invention is described in detail below. However, the following detailed description and the accompanying drawings do not limit the invention.

[0014] The container of the present invention is a hollow container provided above a hollow column provided around a liquefied gas pump, and a cable for installing and extracting the liquefied gas pump passes through the center of the container from the bottom to the top of the container. The container comprises: a lower plate member provided at the bottom of the container and having a cable through hole in the center through which the cable can pass; and a stuffing box member provided in the center of the lower plate member around the cable through hole and having a cable insertion hole in the center through which the cable is inserted, and the stuffing box member is provided with an opening diameter adjustment mechanism for adjusting the size of the opening diameter of the cable insertion hole.

[0015] According to this configuration, a stuffing box member is provided around the cable through hole, and the stuffing box member is provided with an opening diameter adjustment mechanism that adjusts the opening diameter of the cable insertion hole. Therefore, by adjusting the opening diameter of the cable insertion hole using the opening diameter adjustment mechanism of the stuffing box member, it is possible to reduce gas leaking from the cable through hole.

[0016] In addition, in the container of the present invention, the opening diameter adjustment mechanism may include a rotating ring member that can rotate around the central axis of the cable insertion hole, a pair of upper and lower linear ring members that are provided on the upper and lower sides of the rotating ring member, respectively, and are slidable along the central axis of the cable insertion hole, and a pair of upper and lower cloth members that are fixed at both ends to the linear ring member and the rotating ring member for each of the pair of upper and lower linear ring members and are provided to cover the linear ring member and the rotating ring member, and a pair of upper and lower cable insertion holes are formed by the pair of upper and lower cloth members, and by rotating the rotating ring member, the opening diameters of the pair of upper and lower cable insertion holes can be adjusted simultaneously.

[0017] According to this configuration, the opening diameter adjustment mechanism is made up of the rotary ring member, the pair of upper and lower linear ring members, and the cloth member, and the pair of upper and lower cable insertion holes are formed by the pair of upper and lower cloth members. Then, by rotating the rotary ring member, the opening diameters of the pair of upper and lower cable insertion holes can be adjusted simultaneously.

[0018] In the container of the present invention, the rotary ring member may be provided with a gas inlet for allowing a purge gas to flow into the interior of the rotary ring member.

[0019] According to this configuration, purge gas can be introduced into the interior of the rotating ring member through the gas inlet provided in the rotating ring member. The purge gas that has entered the interior of the rotating ring member flows upward and downward within the rotating ring member. As a result, even if gas attempts to flow downward from above the linear motion ring member above the rotating ring member, the purge gas flowing upward can prevent the gas from flowing in. Furthermore, even if gas attempts to flow upward from below the linear motion ring member below the rotating ring member, the purge gas flowing downward can prevent the gas from flowing in.

[0020] In the container of the present invention, the rotary ring member, the linearly moving ring member, and the fabric member may each be splittable into two states from a closed state to an open state.

[0021] According to this configuration, the rotary ring member and the linear ring member can be split into two, so that the opening diameter adjustment mechanism can be attached to the cable from the middle of the cable by changing the ring from an open state to a closed state inside the container. Also, the opening diameter adjustment mechanism can be removed from the cable from the middle of the cable by changing the ring from a closed state to an open state.

[0022] In addition, in the container of the present invention, the opening diameter adjustment mechanism may include an annular main body member having a cable insertion hole in the center, a pair of left and right plate-like sealing members that are openably and closably provided on the upper and lower sides of the main body member, and a spring member that biases each of the pair of left and right sealing members in a direction to close them toward the center, wherein a cable insertion hole is formed in the center of the pair of left and right sealing members, and the size of the opening diameter of the cable insertion hole can be adjusted by moving the pair of left and right sealing members in an opening direction against the elastic force of the spring member.

[0023] With this configuration, the opening diameter adjustment mechanism is made up of the main body member, the seal member, and the spring member, and the cable insertion hole is formed in the center of the pair of left and right seal members. Then, by moving the pair of left and right seal members in the opening direction against the elastic force of the spring member, the opening diameters of the pair of upper and lower cable insertion holes can be adjusted simultaneously.

[0024] In the container of the present invention, the body member may be provided with a gas inlet for allowing a purge gas to flow into the body member.

[0025] According to this configuration, purge gas can be introduced into the main body member through the gas inlet provided in the main body member. The purge gas that has introduced into the main body member flows upward and downward within the main body member. As a result, even if gas attempts to flow from the upper side of the main body member (from above to below), the purge gas flowing toward the upper side can prevent the gas from flowing in. Furthermore, even if gas attempts to flow from the lower side of the main body member (from below to above), the purge gas flowing toward the lower side can prevent the gas from flowing in.

[0026] In the container of the present invention, the main body member may be splittable in two in the direction in which the pair of left and right seal members open.

[0027] According to this configuration, since the main body member can be split into two, the opening diameter adjustment mechanism can be attached to the cable from the middle part of the cable inside the container, or the opening diameter adjustment mechanism can be detached from the cable from the middle part of the cable.

[0028] The container of the present invention may also include a glove box provided inside the container and configured to allow a user to insert their hands from outside the container to operate the stuffing box members, and an access window located near the glove box and the stuffing box members so that the glove box and the stuffing box members can be viewed from outside the container.

[0029] According to this configuration, when performing maintenance on the liquefied gas pump, the user can insert their hand from outside the container into the glove box inside the container (purge container) and use the opening diameter adjustment mechanism of the stuffing box member to adjust the size of the opening diameter of the cable insertion hole, thereby reducing the amount of gas leaking from the cable pass-through hole.

[0030] A pump system of the present invention includes a liquefied gas pump and any of the containers described above.

[0031] In this pump system, as in the container described above, a stuffing box member is provided around the cable insertion hole, and the stuffing box member is provided with an opening diameter adjustment mechanism that adjusts the opening diameter of the cable insertion hole. Therefore, by adjusting the opening diameter of the cable insertion hole using the opening diameter adjustment mechanism of the stuffing box member, it is possible to prevent gas from leaking from the cable insertion hole.

[0032] According to the present invention, it is possible to prevent gas from leaking from the cable passing-through hole.

[0033] Hereinafter, a container according to an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a container used in a pump system or the like equipped with a liquefied gas pump for delivering a cryogenic liquefied gas such as liquefied hydrogen or liquefied ammonia will be described as an example.

[0034] The configuration of a container according to an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 and 2 are explanatory diagrams showing a pump system according to this embodiment. As shown in FIGS. 1 and 2, the pump system 1 includes a liquefied gas pump P. The liquefied gas pump P in one embodiment is a pump for cryogenic liquefied gas, such as a liquid hydrogen pump or a liquefied ammonia pump. The pump system 1 further includes a hollow column 2 disposed around the liquefied gas pump P, a hollow buffer container 3 disposed above the column 2, and a hollow purge container 4 disposed above the column 2 and above the buffer container 3. The buffer container 3 and the purge container 4 are collectively referred to as a "container." This container is hollow and disposed above the hollow column 2 disposed around the liquefied gas pump P.

[0035] The buffer container 3 includes a buffer lower plate 5 that is provided on the underside of the buffer container 3 and can be opened and closed upward. The purge container 4 includes a container lower plate 6 that is provided on the underside of the purge container 4 and can be opened and closed upward, and a container upper plate 7 that is provided on the upper side of the purge container 4 and can be opened and closed upward.

[0036] A cable 8 for installing and extracting the liquefied gas pump P passes through the center of the container from the bottom to the top of the container. The buffer lower plate 5 has a cable through hole 9 in its center through which the cable 8 can pass, the container lower plate 6 has a cable through hole 10 in its center through which the cable 8 can pass, and the container upper plate 7 has a cable through hole 11 in its center through which the cable 8 can pass. A stuffing box 12 is provided around the cable through hole 9 in the center of the buffer lower plate 5. Furthermore, a stuffing box 12 is provided around the cable through hole 10 in the center of the container lower plate 6. Furthermore, a stuffing box 12 is provided around the cable through hole 11 in the center of the container upper plate 7.

[0037] 12 and 13 , the container 3 may also include a glove box 30 configured to allow a user to insert their hand from outside the buffer container 12 in order to operate the stuffing box 12, and an access window 31 located near the glove box 30. The stuffing box 12 and the glove box 30 inside the buffer container 3 can be seen from outside the buffer container 3 through the access window 31.

[0038] Furthermore, in this pump system 1, the purge container 4 includes a glove box 32 configured to allow a user to insert their hands from outside the purge container 4 to operate the stuffing box 12, and an access window 33 located near the glove box 32. The stuffing box 12 and the glove box 32 of the purge container 4 can be seen from outside the purge container 4 through the access window 33.

[0039] In this case, when operating the opening diameter adjustment mechanism of the stuffing box 12 for maintenance of the liquefied gas pump, there is no need to open the container to put one's hand inside the container, so it is possible to prevent air from entering the barrier zone or the liquid from leaking out of the partition chamber (container) as in the conventional case, which would otherwise occur if one were to put one's hand inside the partition chamber (container).

[0040] In addition, in the container of the present invention, the buffer container 4 may be provided with a second glove box 34 configured to allow a user to insert their hand from outside the container to perform manual work inside the container, and a second work window 35 arranged near the second glove box 34 so that the inside of the buffer container 4 can be viewed from outside the buffer container.

[0041] With this configuration, when performing maintenance on the liquefied gas pump, a user can insert their hands from outside the container into the second glove box 32 inside the container and perform work inside the container. In this case, when performing manual work inside the container for maintenance of the liquefied gas pump, there is no need to open the container to insert their hands inside. Therefore, it is possible to prevent air from entering the barrier zone or the liquid from leaking out of the container, which would occur when a user inserts their hands inside the container as in the conventional case.

[0042] The maintenance method for a liquefied gas pump according to the present invention includes a step in which a user inserts his / her hand from outside the container into a glove box 30, 32, 34 provided inside the container, and operates the opening diameter adjustment mechanism of the stuffing box 12 provided inside the container to hang down the liquefied gas pump.

[0043] As with the container described above, this maintenance method also eliminates the need to open the container to insert a hand into it when operating the opening diameter adjustment mechanism of the stuffing box 12 for maintenance of the liquefied gas pump. This prevents air from entering the barrier zone or the liquid from leaking out of the container, which would otherwise occur if a person were to insert their hand into the container, as in the conventional case.

[0044] 3 to 7 are explanatory diagrams showing the stuffing box 12 of this embodiment. A cable insertion hole 13, through which the cable 8 is inserted, is provided in the center of the stuffing box 12. The stuffing box 12 is equipped with an opening diameter adjustment mechanism 14 that adjusts the size of the opening diameter of the cable insertion hole 13.

[0045] 3 and 4, the opening diameter adjustment mechanism 14 includes a rotary ring 15 that can rotate around the central axis of the cable insertion hole 13, and a pair of upper and lower linear motion rings 16 that are provided above and below the rotary ring 15 and can slide along the central axis of the cable insertion hole 13. Both ends of each of the pair of upper and lower linear motion rings 16 are fixed to the linear motion ring 16 and the rotary ring 15, and a pair of upper and lower cloths 17 are provided cylindrically so as to cover the peripheries of the linear motion ring 16 and the rotary ring 15. The pair of upper and lower cloths 17 form the pair of upper and lower cable insertion holes 13.

[0046] It is desirable that the material for the pair of upper and lower cloths 17 be flexible, airtight, and resistant to fraying and surface chipping at extremely low temperatures. Table 1 below shows the results of tests conducted to confirm the flexibility, airtightness, and presence or absence of fraying and surface chipping at extremely low temperatures for four materials (materials A to D).

[0047]

[0048] Here, material A used was "Kevlar (registered trademark)", a para-aramid fiber manufactured by DuPont-Toray Co., Ltd.; material B used was "silicone-coated heat-resistant sheet flame retardant KW-031" manufactured by Kikuchi Sheet Kogyo Co., Ltd.; material C used was "double-sided silicone-coated synthetic fiber heat-resistant sheet" manufactured by Kikuchi Sheet Kogyo Co., Ltd.; and material D used was "Achilles Frigo Soft, cold-resistant sheet for room partitions" manufactured by Achilles Corporation.

[0049] Test specimens of materials A through D were immersed in liquid nitrogen and thoroughly cooled. After removal from the liquid nitrogen, the specimens were twisted. The specimens were then visually inspected for the maintenance of flexibility and for the absence of defects such as chips or fraying on the surface. The airtightness of the specimens was also confirmed by a simple gas test (e.g., a test in which the test apparatus was divided into two compartments for each material, one compartment filled with a specific gas and the other with air, and the increase in the gas concentration in the other compartment after a certain period of time was measured). The results in Table 1 indicate that material B or material C is desirable for the upper and lower cloth pair 17.

[0050] The rotating ring 15 is provided with a rotation lever 18, and by inserting a hand from the glove box and operating the rotation lever 18 to rotate the rotating ring 15, the opening diameters of the pair of upper and lower cable insertion holes 13 can be simultaneously adjusted. In this case, by applying a rotational motion to one end of the cylindrically arranged cloth 17 with the rotation lever 18, the cloth 17 is twisted, narrowing the diameter of the cylinder, and as a result, the cloth 17 can be tightly fitted around the outer periphery of the cable 8. As a result, the cloth 17 clings to the installation / pulling cable 8, narrowing the gas flow path and suppressing gas leakage. Furthermore, when moving the cable 8 up and down, such as when storing the liquefied gas pump P below the column 2 or when pulling the liquefied gas pump P up and out of the column 2, applying a rotational motion with the rotation lever 18 in the direction opposite to the twisting direction untwists the cloth 17, widening the diameter of the cylinder, and as a result, creating a space between the outer periphery of the cable 8 and the cloth 17. Therefore, the installation / pulling cable 8 can be moved up and down without interfering with the fabric 17. In this way, the opening diameter adjustment mechanism 14 not only adjusts the degree of constriction according to the diameter of the cable 8, but also changes the opening diameter according to the work, and can be opened and closed repeatedly.

[0051] 5 and 6, the rotating ring 15, the linear motion ring 16, and the cloth 17 can each be split into two, from a closed state to an open state. This makes it possible to attach and detach the stuffing box 12 while the cable 8 is inserted through the container. Also, by adjusting the degree of constriction according to the diameter of the cable 8, leakage can be suppressed even for cables 8 with locally different diameters.

[0052] As shown in Figures 3 to 4 and 7, the rotary ring 15 is provided with a gas inlet 19 for introducing a purge gas into the rotary ring 15. Examples of purge gases that can be used include nitrogen gas and helium gas. As shown in Figure 7, the purge gas flows from the interior of the stuffing box 12 to the top and from the interior of the stuffing box 12 to the bottom, which has the effect of preventing the flow of gas falling from the top to the bottom of the container and preventing the flow of gas leaking from the bottom to the top of the container. This makes it possible to prevent the leakage of highly dangerous gases such as ammonia and hydrogen to the outside and the falling of air and nitrogen into the column 2.

[0053] In this case too, by operating the rotating lever 18 depending on whether the cable 8 is not moving or whether the cable 8 is moving up or down, the space between the outer periphery of the cable 8 and the cloth 17 can be closed or opened to an appropriate interval, thereby making it possible to adjust the flow rate passing through that space and preventing the use and release of a large amount of purge gas unnecessarily.

[0054] According to the container of this embodiment, stuffing boxes 12 are provided around the cable through holes 9, 10, and 11, and the stuffing boxes 12 are provided with opening diameter adjustment mechanisms 14 that adjust the size of the opening diameter of the cable insertion holes 13. Therefore, by adjusting the size of the opening diameter of the cable insertion holes 13 using the opening diameter adjustment mechanisms 14 of the stuffing boxes 12, it is possible to reduce gas leaking from the cable through holes.

[0055] In this embodiment, the opening diameter adjustment mechanism 14 is configured by the rotary ring 15, the pair of upper and lower linear rings 16, and the cloth 17, and the pair of upper and lower cable insertion holes 13 are formed by the pair of upper and lower cloths 17. Then, by rotating the rotary ring 15, the opening diameters of the pair of upper and lower cable insertion holes 13 can be adjusted simultaneously.

[0056] Furthermore, in this embodiment, purge gas can be introduced into the interior of the rotary ring 15 through gas inlet 19 provided in the rotary ring 15. The purge gas that has flowed into the interior of the rotary ring 15 flows upward and downward within the rotary ring 15. As a result, even if gas attempts to flow downward from above the linear ring 16 above the rotary ring 15, the purge gas flowing upward can prevent the gas from flowing in. Furthermore, even if gas attempts to flow upward from below the linear ring 16 below the rotary ring 15, the purge gas flowing downward can prevent the gas from flowing in.

[0057] Furthermore, in this embodiment, the rotary ring 15, the linear motion ring 16, and the cloth 17 can be split into two, so that by changing the state of the rings from an open state to a closed state inside the container, the opening diameter adjustment mechanism 14 can be attached to the cable 8 at the intermediate portion of the cable 8. Furthermore, by changing the state of the rings from a closed state to an open state, the opening diameter adjustment mechanism 14 can be detached from the cable 8 at the intermediate portion of the cable 8.

[0058] In addition, the containers (buffer container 3, purge container 4) of this embodiment may be provided with a glove box 30 that is provided inside the container and configured so that a user can insert their hand from outside the container to operate the stuffing box 12, and an access window 31 that is arranged near the glove box 30 and the stuffing box 12 so that the glove box 30 and the stuffing box 12 can be seen from outside the container.

[0059] According to this configuration, when performing maintenance on the liquefied gas pump, the user can insert their hand from outside the container into the glove box 30 inside the container (purge container 3) and adjust the size of the opening diameter of the cable insertion hole 13 using the opening diameter adjustment mechanism 14 of the stuffing box 12, thereby reducing the amount of gas leaking from the cable pass-through hole.

[0060] The above describes the embodiments of the present invention by way of example, but the scope of the present invention is not limited to these, and can be changed or modified according to the purpose within the scope of the claims.

[0061] 8 to 11 show other examples of the opening diameter adjustment mechanism 20. As shown in FIGS. 8 to 11 , the opening diameter adjustment mechanism 20 may include an annular main body 21 having a cable insertion hole 13 in its center, and a pair of left and right plate-shaped seal members 22 that are openably and closably provided on the upper and lower sides of the main body 21. In this case, the cable insertion hole 13 is formed in the center of the pair of left and right seal members 22, and the pair of left and right seal members 22 are biased in a direction to close toward their centers by the elastic force of a pressing spring 23. The pair of left and right seal members 22 move in an opening direction against the elastic force of the pressing spring 23, thereby adjusting the opening diameter of the cable insertion hole 13.

[0062] 8 and 9, by providing tapered portions 25, 26 on the link 24 attached to the cable 8 and the sealing material 22, respectively, the opening diameter of the cable insertion hole 13 can be changed simply by lifting and lowering the cable 8, improving workability. Also, the main body 21 of the opening diameter adjustment mechanism 20 is provided with a gas inlet 19 for allowing purge gas to flow into the main body 21. Furthermore, the main body 21 of the opening diameter adjustment mechanism 20 can be split into two in the direction in which the pair of left and right sealing materials 22 open.

[0063] In this other embodiment, the opening diameter adjustment mechanism 20 is also made up of the main body 21, the seal material 22, and the pressing spring 23, and the cable insertion hole 13 is formed in the center of the pair of left and right seal materials 22. Then, by moving the pair of left and right seal materials 22 in the opening direction against the elastic force of the pressing spring 23, the opening diameters of the pair of upper and lower cable insertion holes 13 can be adjusted simultaneously.

[0064] In this case, purge gas can be introduced into the main body 21 through the gas inlet 19 provided in the main body 21. The purge gas that has introduced into the main body 21 flows upward and downward within the main body 21. As a result, even if gas attempts to flow from the upper side of the main body 21 (from above to below), the purge gas flowing upward can prevent the gas from flowing in. Furthermore, even if gas attempts to flow from the lower side of the main body 21 (from below to above), the purge gas flowing downward can prevent the gas from flowing in.

[0065] Also in this case, since the main body 21 of the opening diameter adjustment mechanism 20 can be split into two, the opening diameter adjustment mechanism 20 can be attached to the cable 8 at the middle part of the cable 8 inside the container, or the opening diameter adjustment mechanism 20 can be detached from the cable 8 at the middle part of the cable 8.

[0066] As described above, the container according to the present invention has the effect of preventing gas leakage from the cable pass-through hole, and is useful as a pump system equipped with a liquefied gas pump that delivers cryogenic liquefied gas such as liquefied hydrogen or liquefied ammonia.

[0067] DESCRIPTION OF SYMBOLS 1 Pump system 2 Column 3 Buffer container (container) 4 Purge container (container) 5 Buffer lower plate (lower plate member) 6 Container lower plate (lower plate member) 7 Container upper plate 8 Cable 9 Cable through hole 10 Cable through hole 11 Cable through hole 12 Stuffing box (stuffing box member) 13 Cable insertion hole 14 Opening diameter adjustment mechanism 15 Rotating ring 16 Linear ring 17 Cloth 18 Rotation lever 19 Gas inlet 20 Opening diameter adjustment mechanism 21 Main body 22 Sealing material 23 Compression spring 24 Link 25 Tapered portion 26 Tapered portion 30 Glove box 31 Working window 32 Glove box 33 Working window 34 Glove box 35 Working window P Liquefied gas pump

Claims

1. A hollow container provided above a hollow column provided around a liquefied gas pump, a cable for installing and extracting the liquefied gas pump passes through a central portion of the container from the bottom to the top of the container, the container comprising: a lower plate member provided at the bottom of the container and having a cable through hole in the central portion through which the cable can pass; and a stuffing box member provided in the central portion of the lower plate member around the cable through hole and having a cable insertion hole in the central portion through which the cable is inserted, the stuffing box member comprising an opening diameter adjustment mechanism for adjusting the size of the opening diameter of the cable insertion hole.

2. The container according to claim 1, wherein the opening diameter adjustment mechanism comprises: a rotating ring member rotatable around the central axis of the cable insertion hole; a pair of upper and lower linear motion ring members respectively provided on the upper and lower sides of the rotating ring member and slidable along the central axis of the cable insertion hole; and a pair of upper and lower cloth members for each of the pair of upper and lower linear motion ring members, both ends of which are fixed to the linear motion ring member and the rotating ring member and which are provided to cover the linear motion ring member and the rotating ring member, wherein the pair of upper and lower cable insertion holes are formed by the pair of upper and lower cloth members, and the size of the opening diameter of the pair of upper and lower cable insertion holes can be simultaneously adjusted by rotating the rotating ring member.

3. The container according to claim 2, wherein said rotating ring member is provided with a gas inlet for allowing a purge gas to flow into the interior of said rotating ring member.

4. A container as described in claim 2 or 3, wherein the rotating ring member, the linear motion ring member and the fabric member are each capable of being split into two from a closed ring state to an open ring state.

5. A container as claimed in claim 1, wherein the opening diameter adjustment mechanism comprises: an annular main body member having the cable insertion hole in a central portion; a pair of left and right plate-shaped sealing members each provided to be openable and closable on the upper and lower sides of the main body member; and a spring member which biases the pair of left and right sealing members in a direction to close each of the pair of left and right sealing members towards the central portion, wherein the cable insertion hole is formed in the central portion of the pair of left and right sealing members, and the size of the opening diameter of the cable insertion hole can be adjusted by moving the pair of left and right sealing members in the opening direction against the elastic force of the spring member.

6. The container of claim 5, wherein said body member is provided with a gas inlet for admitting a purge gas into the interior of said body member.

7. A container according to claim 5 or 6, wherein said main body member can be split into two in the direction in which said pair of left and right seal members open.

8. The container according to claim 1, comprising: a glove box provided inside the container and configured to allow a user to insert their hands from outside the container to operate the stuffing box member; and an access window disposed near the glove box and the stuffing box member so that the glove box and the stuffing box member can be viewed from outside the container.

9. A pump system comprising: a liquefied gas pump; and a container according to any one of claims 1 to 8.

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