JP5034658B2 - Sloshing suppression device for floating roof tank - Google Patents

Description

  The present invention relates to a floating roof tank in which a floating roof is formed on a storage liquid such as an oil tank, and the sloshing of the floating roof tank for quickly calming down the sloshing generated in the storage liquid inside the tank. The present invention relates to a suppression device.

  As a large tank for storing crude oil or oil, which is a fluid with a relatively low risk of vaporization, a floating roof type storage tank is often used. FIG. 5 shows a general structure of a floating roof tank. An upper portion of a bottom plate 2 installed on a foundation and a cylindrical side plate 3 standing on the upper side of the bottom plate 2 is opened. A tank body 1 is provided, and a floating roof 5 is provided that floats on the liquid surface of the liquid 4 stored inside the tank body 1. A pontoon 6 for providing buoyancy is provided on the outer periphery of the floating roof 5. 7 is a sealing device for filling a gap between the outer periphery of the floating roof 5 and the inner peripheral surface of the side plate 3, and 8 is a weather shield for suppressing inflow of rainwater.

  By the way, when an earthquake occurs, when the seismic wave includes a sloshing period component of the floating roof type tank, sloshing is excited in the storage liquid 4 in the floating roof type storage tank. In this manner, once sloshing is excited in the storage liquid 4, since the attenuation of the liquid 4 is small, it is difficult for the sloshing to subside for a long time even after the end of the earthquake.

  Therefore, the sloshing of the stored liquid 4 in the floating roof tank is caused by the liquid 4 overflowing or by the sliding of the sealing device 7 for a long time due to the long pitching vibration of the floating roof 5. There is also a concern about the possibility of causing damage, damage to the weather shield 8, and further damage to the floating roof 5 itself.

  Therefore, in the floating roof type tank, it has been desired that the sloshing of the stored liquid 4 is promptly settled to prevent the possibility of the above-described pitching vibration occurring on the floating roof 5.

  As a method for suppressing the sloshing of the stored liquid in this type of floating roof tank, for example, a resistance plate is suspended below the floating roof 5 via a wire or a spring (for example, see Patent Document 1). It has been considered to move the partition plate attached to the required position of the bottom plate of the tank body in a direction to suppress the sloshing of the stored liquid using a cable or pulley, or to install a shock absorbing mechanism by air pressure, etc. ing.

JP-A-9-142575

  However, the above-mentioned conventionally proposed methods are considered to be effective for suppressing the sloshing of the floating roof type tank, but all of them have complicated mechanisms such as having moving parts. is there.

  Therefore, the present invention is intended to provide a sloshing suppression device for a floating roof type tank that has a simple structure that does not have a movable part and that can efficiently suppress sloshing of stored liquid in the floating roof type tank.

In order to solve the above-mentioned problem, the present invention corresponds to claim 1 and is provided in a floating roof type tank , and a pontoon provided on the outer peripheral portion and a roof portion on the inner peripheral side of the pontoon on the outer peripheral portion. The floating outside of the tank is disposed on the bottom side of the floating roof pontoon only at a position where it does not overlap in plan view with the roof portion of the floating roof. a structure having an inclined plate mounted so as to upwardly inclined.

Furthermore, in each said structure, it is set as the structure which attached the even number of inclination board to the circumferential direction equal interval in the lower side of the pontoon of a floating roof.

Furthermore, in the said structure, it is set as the structure which attached the 6 or more even number of inclination board to the circumferential direction in the lower side of the pontoon of a floating roof.

In each arrangement described above, a plurality of locations in the circumferential Direction at the outer peripheral edge of the pontoon of the floating roof, provided a communicating hole communicating with the tank, and for communicating the respective communication holes to each other, on the upper side of the floating roof Thus, a configuration is adopted in which all the communication holes are connected to each other through one liquid movement pipe extending in the radial direction from the tank center position.

According to the sloshing suppressing device for a floating roof type tank of the present invention, the following excellent effects are exhibited.
(1) In the floating roof tank, the floating roof comprising a roof portion of the inner peripheral side of the pontoons of the pontoon and the outer peripheral portion is provided on an outer peripheral portion, a lower pontoon of the floating roof , only in a position that does not overlap in plan view and the roof portion of the floating roof, via the strut members, a structure having an inclined plate mounted as a radial direction outer side of the floating roof tank is inclined upwardly Therefore, when an outward flow in the tank radial direction of the stored liquid in the tank is generated near the inclined plate mounting location, a downward load can be applied to the floating roof above the inclined plate, The rise of the surface can be suppressed. In addition, when an inward flow of the stored liquid in the tank occurs in the vicinity of the inclined plate mounting location, an upward load can be applied to the floating roof above the inclined plate, Can be suppressed. Therefore, the effect of efficiently suppressing the sloshing of the stored liquid in the floating roof tank can be obtained with a simple apparatus configuration having no movable part.
(2) By attaching the inclined plate to the lower side of the pontoon provided on the outer periphery of the floating roof via a support member, the attachment strength of the inclined plate to the floating roof shall be high. Can do.
(3) By adopting a structure in which an even number of inclined plates are attached at equal intervals in the circumferential direction on the lower side of the pontoon of the floating roof, a floating roof is formed by a set of inclined plates arranged at positions opposed to each other by 180 degrees. Since a downward load can be applied simultaneously to a portion located on the downstream side in the liquid movement direction and an upward load can be applied simultaneously to a portion located on the upstream side in the liquid movement direction. Liquid sloshing can be more efficiently suppressed.
(4) The sloshing of the stored liquid in any horizontal direction in the floating roof tank by adopting a configuration in which an even number of six or more inclined plates are attached in the circumferential direction below the pontoon of the floating roof. Even if this occurs, it becomes possible to exert the effect of suppressing sloshing.
(5) in the circumferential direction a plurality of locations toward the outer periphery of the pontoon of the floating roof, provided a communicating hole communicating with the tank, and for communicating the respective communication holes to each other, the tank center at the upper side of the floating roof the single fluid transfer pipe extending radially from the position by a structure in which all connected communication hole between the communication, in a state of being filled with storage liquid in the tank into the liquid movement piping, the When the floating roof is tilted due to sloshing in the liquid in the tank, the liquid moving pipe is passed through the liquid moving pipe from the communication hole located at the upper part of the inclined floating roof toward the communication hole located at the lower part. The liquid can be circulated, and the sloshing energy generated in the liquid in the tank can be consumed by friction generated when the liquid circulates in the liquid moving pipe. Since that can, effect of quickly converge the sloshing that occurs in the liquid can be expected.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  1 (a) (b) and FIG. 2 (b) (b) show an embodiment of the sloshing suppression device for a floating roof tank according to the present invention, and the floating structure is the same as that shown in FIG. Inclinations whose outer sides are inclined upward at six circumferentially equidistant locations on the lower side of the pontoon 6 provided on the outer peripheral portion of the floating roof 5, for example, circumferentially required portions on the outer peripheral portion of the floating roof 5 in the roof type tank A plate 9 is arranged, and each inclined plate 9 is attached to the lower surface side of the pontoon 6 through a vertical column member 10.

  More specifically, each of the inclined plates 9 has a fan shape that curves along the circumferential curved shape of the pontoon 6.

  Each said inclination board 9 is arrange | positioned so that the outer side may incline upward at a required inclination angle along the radial direction of a floating roof type tank, for example in the position about 1 m below the pontoon 6. FIG. Furthermore, each said inclination board 9 is made to attach through the support | pillar member 10 to the lower surface side of the location corresponding to the internal partition in the said pontoon 6, for example, the required several places of the upper surface side. As a result, as shown in FIG. 2 (a), the stored liquid 4 existing in the vicinity of the installation location of the inclined plate 9 in the floating roof type tank is aligned along the radial direction of the floating roof type tank as indicated by the arrow a. When an outward flow occurs, the liquid 4 is compressed to increase the pressure on the upper side of the inclined plate 9 arranged so that the outer side in the tank radial direction is inclined upward. Since the liquid 4 is diffused below the pressure 9 and the pressure is lowered, the downward inclination of the inclined plate 9 as indicated by the arrow x is applied to the inclined plate 9 according to the pressure difference of the liquid 4 generated above and below the inclined plate 9. A load can be applied.

  In addition, as shown in FIG. 2B, in the case where an inward flow occurs along the radial direction of the floating roof tank as indicated by the arrow b in the stored liquid 4 existing in the vicinity of the place where the inclined plate 9 is installed. The liquid 4 is diffused on the upper side of the inclined plate 9 arranged in a state where the outer side in the tank radial direction is inclined upward, that is, in a state where the inner side in the tank radial direction is inclined downward. While the pressure is lowered, the liquid 4 is compressed and the pressure is increased below the inclined plate 9, so that the inclined plate 9 has a pressure corresponding to the pressure difference between the liquid 4 generated above and below the inclined plate 9. An upward load as indicated by an arrow y can be applied.

  In addition, the magnitude | size of the upward or downward load which acts on each inclination board 9 resulting from the flow along the radial direction of the stored liquid 4 in a floating roof type tank as mentioned above is each inclination board. 9 increases as the tilt angle from the horizontal direction increases. Therefore, the inclination angle of each inclined plate 9 from the horizontal direction is required for the column member 10 for transmitting the vertical load that acts on each inclined plate 9 to the pontoon 6 for support. It may be set as appropriate in consideration of the strength.

  Other configurations are the same as those shown in FIG. 5, and the same components are denoted by the same reference numerals.

  When a seismic wave including a sloshing period component of the floating roof tank is caused by the occurrence of an earthquake on the floating roof tank equipped with the sloshing suppression device having the above configuration, the storage liquid 4 in the floating roof storage tank is Sloshing is excited. The sloshing of the stored liquid 4 is caused by the movement of the stored liquid 4 in the floating roof tank, and the liquid level rises at the downstream side in the moving direction of the liquid 4 and the upstream in the moving direction of the liquid 4. This occurs because the liquid level is lowered at the location on the side, but the liquid 4 flows radially outward at the location on the downstream side in the moving direction of the stored liquid 4. Therefore, as shown in FIG. 2 (a), a downward load as shown by the arrow x is applied to the inclined plate 9 attached to the location. For this reason, upward displacement is suppressed in the portion of the floating roof 5 to which the inclined plate 9 is attached via the column member 10.

  On the other hand, since the liquid 4 flows inward in the radial direction at the location upstream of the moving direction of the stored liquid 4 due to the sloshing, it is attached to the location as shown in FIG. An upward load as indicated by an arrow y acts on the inclined plate 9. For this reason, in the part of the floating roof 5 to which the inclined plate 9 is attached via the column member 10, the downward displacement can be suppressed.

  Therefore, the floating roof 5 existing on the upper side of the storage liquid 4 suppresses the displacement of the liquid surface due to the sloshing of the storage liquid 4, so that the sloshing of the storage liquid 4 can be quickly subsided. .

  Thus, according to the sloshing suppression device for the floating roof type tank of the present invention, the inclined plate 9 is attached to the lower side of the outer peripheral portion of the floating roof 5 through the support member 10 and has a simple structure with no moving part. The sloshing of the storage liquid 4 can be efficiently suppressed.

  Moreover, in the above, since each inclination board 9 is attached to the lower side of the pontoon 6 of the floating roof 5, the attachment intensity | strength of each inclination board 9 can be made high.

  In addition, since each of the inclined plates 9 is provided in an even number in the circumferential direction at the circumferential direction of the floating roof 5, a set of inclined plates 9 arranged at positions opposed to each other by 180 degrees. Thus, a downward load can be applied simultaneously to a portion of the floating roof 5 located downstream in the liquid 4 movement direction, and an upward load can be applied simultaneously to the portion located upstream of the liquid 4 movement direction. it can. For this reason, the sloshing of the liquid 4 can be efficiently suppressed. Furthermore, even if sloshing of the liquid 4 occurs in any direction in the horizontal direction in the floating roof type tank, any one or two of the three sets of inclined plates 9 disposed at the positions opposed to each other by 180 degrees. The slanting suppression effect by suppressing the vertical displacement of the floating roof 5 as described above can be exhibited by the pair of inclined plates 9. Therefore, it is possible to expect the effect that it is possible to cope with sloshing of the liquid 4 in any horizontal direction in the floating roof tank.

  Next, FIGS. 3 (a) (b) and 4 show other embodiments of the present invention, which are the same as those shown in FIGS. 1 (a) (b) and 2 (a) (b). In the configuration, communication holes 11 communicating with the inside of the tank are provided at a plurality of circumferentially required intervals on the outer peripheral edge of the floating roof 5, for example, the outer peripheral edge of the pontoon 6. It is connected to the upper side of the roof 5 through a liquid moving pipe 12 arranged to extend in the radial direction from the tank center position.

  The liquid moving pipe 12 is flexible enough to follow the bending of the floating roof 5 and the pontoon 6.

  The liquid moving pipe 12 is filled with the stored liquid 4 in the floating roof tank. As a method for filling the storage liquid 4 in the liquid moving pipe 12 in this manner, for example, when the floating roof tank supplies the storage liquid 4 from above, the liquid 4 is not shown. If the supply line can be connected to the upper end of the liquid transfer pipe 12 and the liquid transfer pipe 12 is used as a supply path for the storage liquid 4, the storage liquid 4 is filled. Good.

  As another method, for example, an open / close valve (not shown), more preferably an open / close valve or a check valve that allows gas to pass but not liquid, is provided at the upper end of the liquid moving pipe 12. As a configuration, the stored liquid 4 in the tank may be filled in the liquid moving pipe 12 by extracting the gas in the liquid moving pipe 12 from the valve.

  Other configurations are the same as those shown in FIGS. 1A and 1B and FIGS. 2A and 2B, and the same components are denoted by the same reference numerals.

  Also according to this embodiment, the same effect as that of the above embodiment can be obtained. Furthermore, as shown in FIG. 4, when the floating roof 5 is tilted due to sloshing in the stored liquid 4 in the floating roof type tank, it is positioned above the tilted floating roof 5 according to the principle of siphon. The storage liquid 4 in the tank can be circulated through the liquid moving pipe 12 from the communication hole 11 toward the communication hole 11 positioned at the lower part. At this time, the diameter of the liquid moving pipe 12 is appropriately selected in consideration of the viscosity of the liquid 4 so that the liquid 4 flows in the liquid moving pipe 12 while causing friction. Then, the sloshing energy generated in the storage liquid 4 in the tank due to this friction is consumed (dissipated), so that the sloshing generated in the storage liquid 4 can be quickly converged. .

  In addition, this invention is not limited only to the said embodiment, The inclination board 9 is good also as trapezoid or a rectangle instead of a fan shape. Further, the width dimension of the inclined plate 9 along the circumferential direction of the floating roof tank may be appropriately changed within a range in which the bending of the floating roof 5 and the pontoon 6 is not hindered by attaching the inclined plate 9. You may increase / decrease the attachment location of the inclination board 9 in the circumferential direction of the floating roof 5 suitably. In addition, it is preferable that the attachment location of the inclination board 9 in the circumferential direction of the floating roof 5 is an even-number location of the circumferential direction equal intervals. In this way, when the movement of the liquid 4 occurs in the floating roof tank, the inclined plate 9 arranged at a position opposed to 180 degrees is positioned downstream of the floating roof 5 in the liquid 4 movement direction. Since a downward load can be applied simultaneously to the portion to be applied and an upward load can be applied simultaneously to the portion located upstream in the moving direction of the liquid 4, the sloshing of the liquid 4 can be efficiently suppressed. become. Furthermore, if the attachment points of the inclined plate 9 in the circumferential direction of the floating roof 5 are an even number of six or more circumferentially spaced intervals, the liquid 4 can be distributed in all directions in the horizontal direction in the floating roof tank. Even if sloshing occurs, the sloshing can be easily suppressed. Further, the inclined plates 9 may be arranged in the circumferential direction of the floating roof 5 without being spaced apart.

  The distance between the pontoon 6 and the inclined plate 9 provided below the pontoon 6 is that when the height of the floating roof type tank or the floating roof 5 is lowered most with a decrease in the storage amount of the liquid 4 in the tank body 1. You may make it change suitably according to the height dimension etc. from the fixed surface in a tank.

  3 (b) and 4 (a) and 4 (b), communication holes 11 are provided at six locations in the circumferential direction on the outer peripheral portion of the floating roof 5, and the communication holes 11 are connected by a liquid movement pipe. However, the number of communication holes 11 in the circumferential direction of the floating roof 5 may be appropriately increased or decreased.

  Of course, various modifications can be made without departing from the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS One Embodiment of the sloshing suppression apparatus of the floating roof type | mold tank of this invention is shown, (A) is a schematic cut | disconnection side view, (B) is an AA direction arrow directional view of (A). FIGS. 1A and 1B show the operation of the apparatus of FIG. 1, in which (a) shows a case where a radially outward flow occurs in the stored liquid, and (b) shows a case where a radially inward flow occurs in the stored liquid. FIG. The other form of implementation of this invention is shown, (A) is a schematic cut | disconnection side view, (B) is a BB direction arrow directional view of (A). It is a figure which shows the state which the inclination produced in the floating roof of the floating roof-type tank equipped with the apparatus of FIG. It is a schematic side view which shows the general structure of a floating roof type tank.

Explanation of symbols

4 Liquid 5 Floating Roof 6 Pontoon 9 Inclined Plate 10 Strut Member 11 Communication Hole 12 Liquid Movement Pipe

Claims (4)

A floating roof , which is in a floating roof tank , and includes a pontoon provided on the outer peripheral portion and a roof portion on the inner peripheral side of the outer peripheral pontoon , and below the pontoon of the floating roof , the floating located only in that they do not overlap in plan view and the roof portion of the roof, through the strut member, and characterized in that it have a, an inclined plate mounted as a radial direction outer side of the floating roof tank is inclined upwardly Sloshing suppression device for floating roof tanks. Sloshing suppression device floating roof tank according to claim 1 Symbol placement was to attach an even number of inclined plates in the circumferential direction at equal intervals in the lower pontoon of the floating roof. The sloshing suppression device for a floating roof type tank according to claim 2, wherein an even number of six or more inclined plates are attached in a circumferential direction below the pontoon of the floating roof. In the circumferential direction a plurality of locations toward the outer periphery of the pontoon of the floating roof, provided a communicating hole communicating with the tank, and for communicating the respective communication holes to each other, the diameter from the tank center position at the upper side of the floating roof claim 1, 2 or 3 Symbol mounting sloshing suppression device floating roof tanks connected all communication holes together and communication by a single fluid transfer pipe extending in a direction.

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