JP5214299B2 - Sloshing inhibitor - Google Patents

Description

  The present invention relates to a sloshing suppressing material used for a floating roof type liquid storage tank.

  In recent years, many floating storage tanks that can be constructed at low cost have been adopted as liquid storage tanks. However, when a long-period earthquake occurs in the vicinity of a floating roof tank, the liquid in the inside fluctuates, which causes the floating roof to shake, and the liquid leaks from the surroundings of the floating roof, causing the floating roof to sink or shake. When it is severe, the floating roof may be damaged. In addition, if the storage liquid is flammable, sparks generated by friction between the floating roof (ancillary equipment such as a walkway) and the tank wall may ignite the leaked storage liquid and lead to a fire. .

Various techniques for suppressing and reducing such storage liquid and floating roof swing, so-called sloshing height, have been proposed. For example, by joining the pontoons that make up the floating roof with an elastic member, when the liquid surface shakes, the floating roof is deformed in a shape that conforms to the liquid surface shape to absorb the energy of the shaking. Technology (see Patent Document 1), a floating roof with a bag-like structure made of a flexible outer skin and a flexible reinforcing material filled with nonflammable gas, and a cross attached to the lower part of the floating roof There is a technique (see Patent Document 2) for attenuating vibration of a liquid by using a plate-like or lattice-like anti-sway plate.
Japanese Patent Laid-Open No. 2005-289483 JP 2005-178900 A

  In recent years, it has been predicted that large earthquakes are likely to occur in the near future in areas such as the Tokai and Tonankai regions. Not only newly constructed tanks, but also existing tanks are urgently needed. Are required to take measures against sloshing. Nevertheless, the conventional sloshing suppression device has problems such as excessive installation and cost and insufficient suppression effect, and is not fully utilized.

  That is, since the technique of patent document 1 has the special structure of the whole floating roof, in order to apply to an existing tank, cost and an effort take, and it is difficult at the point of spreading widely. In addition, since the vibration energy is absorbed by deforming the floating roof, friction between the floating roof and the inner wall of the tank, which causes a fire, is still inevitable.

  In the technique of Patent Document 2, the entire floating roof has a special structure, and it is costly to spread a large number including existing tanks. In addition, the anti-sway plate at the bottom of the floating roof can suppress the horizontal flow of the storage liquid directly under the floating roof, but it prevents the upward flow of the storage liquid that occurs near the tank side wall, which directly causes sloshing. It is not possible.

  The subject of this invention is providing the sloshing suppression material which can be installed economically and easily and exhibits the high suppression effect, in order to promote the sloshing measures prepared for the big earthquake which may occur in the future.

In order to solve the above-described problems, the invention according to claim 1 is a sloshing suppression material provided in a liquid storage tank having a floating roof, and is a suppression plate supported so as to be vertically movable in the stored liquid; and an air damper that can be expanded and contracted in mounted vertically between the floating roof and the suppression plate, Tona is, inside of the air damper is in communication with the interior airtight pontoon of the floating roof, the suppressing plate, a plurality of split plates arranged in the horizontal direction, the divided plate Rukoto a split plates arranged next to, is connected so as to be rotatable with respect to split plates arranged next to It is characterized by.

The invention described in claim 2 is the anti-sloshing material according to claim 1, wherein the suppression plate is characterized in that mounted side by side a plurality in the vertical direction.

According to the present invention, generally only attaching simple apparatus in the form of a floating roof which is popular, it is possible to include the anti-sloshing function to the tank, a very economical and easily measures to existing tanks Can be applied. And since the air damper attached between the floating roof and the suppression plate absorbs the energy of the upward flow of the stored liquid and suppresses the vertical movement of the stored liquid, it is possible to effectively prevent the floating roof from swinging.
Further, since the inside of the air damper and the inside of the pontoon communicate with each other in an airtight manner, the internal air can be freely communicated and more energy of the upward flow can be absorbed.
Furthermore, when the dividing plate rotates with respect to the adjacent dividing plate, the restraining plate becomes deformed in accordance with the flow of the storage liquid, and not only absorbs the energy of the upward flow but also the liquid level of the storage liquid. Can also be suppressed.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration of an embodiment of a sloshing suppression material to which the present invention is applied. 11 is a main body, 12 is a floating roof, 21 is a suppression plate, and 22 is an air damper.

  The main body 11 of the floating roof type liquid storage tank 1 is generally used for storing liquid, and is a cylindrical structure having an open top. A storage liquid (not shown) is stored inside the main body 11.

  The floating roof 12 has a disk shape slightly smaller than the inner diameter of the main body 11, and floats on the storage liquid to block the storage liquid from the outside. The structure of the floating roof 12 used here is a single deck type, and is composed of a central deck plate 12a and a pontoon 12b arranged in a circle around it. In addition, a plurality of holes (not shown) for communicating with an air damper 22 described later are provided at equal intervals on the lower surface of the pontoon 12b.

  As shown in FIG. 2, the suppression plate 21 constituting the sloshing suppression member 2 is configured such that a plurality of sectors 21 a are combined to form a single disk as a whole. As shown in FIG. 1, the restraining plate 21 is disposed below the floating roof 12 so as to be parallel to the floating roof 12 and immersed in the storage liquid, and an air damper 22 described later is sandwiched between the floating roof 12 and the pontoon 12 b. It is supported so that it can move up and down. Adjacent sectors 21a are connected to each other by a hinge 21b indicated by a broken line in FIG. 2, and the suppression plate 21 has a structure that can be bent.

  Similarly, as shown in FIG. 3A, an air damper 22 which is a swing absorbing means constituting the sloshing suppression material 2 is a columnar device comprising a bag body 22a made of elastic rubber and a plurality of rings 22b surrounding the bag body 22a. As shown in FIG. 3 b, it can be expanded and contracted in the vertical direction. Further, it is made of a material that has enough strength to withstand the compressive force that acts when subjected to compression from the suppression plate 21 described later, and at the same time is not subject to erosion of the stored liquid. The ring 22b may use a spring instead.

  As shown in FIG. 2, a plurality of air dampers 22 are arranged at equal intervals at the positions where the holes on the lower surface of the pontoon 12b described above are provided. The bag body 22a and the pontoon 12b communicate with each other in an airtight manner as described above so that the air inside can be freely communicated. When it is difficult to attach the air damper 22 directly because the lower surface of the pontoon 12b is inclined as shown in FIG. 1, it is attached via the attachment 22c.

  By attaching the sloshing suppression material 2, a space is formed between the floating roof 12 and the suppression plate 21, but there is a gap between the suppression plate 21 and the inner wall of the main body 11, or between the sector 21a and the sector 21a. Therefore, it is possible to store the liquid in this space, and it is possible to recover all the stored liquid from the liquid storage tank 1 without any problem.

  Next, the mechanism of sloshing suppression according to the present invention will be described with reference to FIG. When a long-period earthquake occurs in the vicinity of the liquid storage tank 1, the stored liquid starts to move greatly in the horizontal direction inside the main body 11. The horizontal flow of the storage liquid hits the inner surface of the side wall of the main body 11 and changes the flow upward. If the tank is not provided with anti-sloshing measures, this series of operations is repeated to increase the wave height, and sloshing occurs.

  However, in the liquid storage tank 1 to which the sloshing suppression material 2 is attached, the flow of the stored liquid in the upward direction collides with the suppression plate 21 before reaching the floating roof 12. Then, the suppression plate 21 is pushed up by the stored liquid, and the air damper 22 is compressed. At this time, the air in the bag 22a flows into the pontoon 12b through the hole on the lower surface of the pontoon 12b. Due to this mechanism and the high compressibility of air, even if the suppression plate 21 is pushed up, the air damper 22 is only compressed, and the pontoon 12b on it is not pushed up. Therefore, the energy of the stored liquid can be absorbed without causing the floating roof 12 to swing, and the flow can be converged.

  Further, when the liquid depth of the liquid stored in the main body 11 is increased, the energy of the liquid flow is increased accordingly, and an attempt is made to generate a higher wave when an earthquake occurs. However, the energy absorption capacity of the air damper 22 is extremely high. Since the rocking can be sufficiently suppressed at any liquid depth, the liquid storage tank 1 can be used in a full state at all times.

  The restraining plate 21 and the air damper 22 are relatively lightweight, and even if they are mounted on the floating roof 12, there is no adverse effect such as the floating roof 12 sinking. Rather, the mass of the floating roof 12 increases moderately, so The suppression effect is improved.

  When a long-period earthquake continues, the storage liquid gradually shows a complicated behavior, but as described above, the suppression plate 21 is divided into a plurality of sectors 21a and connected by hinges 21b. Can be modified according to the flow of the stock solution. Therefore, not only the air damper 22 but also the deformation of the suppression plate 21 can absorb the energy of the stored liquid and suppress the undulation of the liquid surface.

  As shown in FIG. 5, a plurality of restraining plates 21 are arranged in advance in a layered manner in the vertical direction, and an air damper 22 is sandwiched between the restraining plates 21 and 21 so that more liquid flow is achieved. Energy can be absorbed, and the effect of suppressing sloshing is further improved.

In the above embodiment, the single deck floating roof is used. However, the present invention is not limited to this and may be a double deck type.
In addition, the shape of the tank body, the type of stored liquid, the spring stiffness of the air damper, the cross-sectional shape, the dimensions and the number of installations, the number of divisions of the restraining plate, the division shape and the connecting means, etc. are arbitrary, and other specific details Of course, it can be appropriately changed.

It is sectional drawing which shows the structure of one Embodiment of the sloshing suppression material to which this invention is applied. It is a top view which shows the structure of one Embodiment of the sloshing suppression material to which this invention is applied. It is a front view which shows the structure of the air damper used for this invention. It is sectional drawing which shows the effect | action of the sloshing suppression material to which this invention is applied at the time of the occurrence of an earthquake. It is sectional drawing which shows the structure of another embodiment of the sloshing suppression material to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid storage tank 11 Main body 12 Floating roof 12a Deck board 12b Pontoon 2 Sloshing suppression material 21 Suppression board 21a Fan shape 21b Hinge 22 Air damper (oscillation absorption means)
22a Bag 22b Ring 22c Attachment

Claims (2)

A sloshing suppression material provided in a liquid storage tank having a floating roof,
A suppression plate which is movable up and down in the stock solution, and an air damper that can expand and contract in the attached vertically between the floating roof and the suppression plate, Ri Tona,
The inside of the air damper is in airtight communication with the inside of the pontoon of the floating roof,
The suppression plate is composed of a plurality of divided plates arranged along the horizontal direction,
Each divider plate includes a dividing plate disposed next to, the anti-sloshing member characterized that you have been connected so as to be rotatable with respect to the divided plate arranged next to it. The sloshing suppression material according to claim 1, wherein a plurality of the suppression plates are attached side by side in the vertical direction .

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