JP5120694B2 - Floating roof of storage tank - Google Patents

Description

  The present invention relates to a floating roof of a storage tank.

  For example, in the device disclosed in Patent Document 1, a floating roof pontoon is formed so that the upper surface is substantially horizontal, and the upper edge portion extending from the upper surface to the outer surface is formed as a diagonal cut surface along the lower surface corresponding portion of the fixed roof. A roof tank is disclosed. Further, in the invention of Patent Document 2, a vertical dam plate for damming the air foam foam fire extinguisher is provided inside the pontoon upper portion of the floating roof, and a pipe extending from the lower end inside of the dam plate to the upper surface of the roof plate is provided. A drainage structure at the upper part of the pontoon of a floating roof is disclosed, which is provided with a self-supporting mechanical emergency shut-off valve that operates by detecting an earthquake in the middle of the process.

Japanese Utility Model Publication No.57-24284 JP-A-2005-239243

In the pontoon of the floating roof tank with a fixed roof of Patent Document 1, when the liquid level during an earthquake vibrates and a so-called sloshing phenomenon occurs, the upper edge of the outer surface of the pontoon does not collide with the lower peripheral surface of the fixed roof to be damaged. It is formed on the inclined surface. Moreover, the pontoon of the floating roof of patent document 2 guides and discharges rainwater collected on the pontoon to the center of the roof, and when the stored liquid intrudes into the upper part of the pontoon due to an earthquake or the like, the intruding liquid spreads over the entire upper part of the roof plate. It is provided with a drainage structure that prevents this.
However, these pontoon type floating roofs such as Patent Document 1 and Patent Document 2 are not intended to preferentially guide the extinguishing agent or the storage liquid between the floating roof and the side plate, and have the following inconveniences. there were.

This inconvenience will be described in detail with reference to an example of a conventional pontoon type floating roof, FIG.
A storage tank 500 illustrated in FIG. 5 includes a side plate 511, in which the storage liquid 20 is stored, and a pontoon type floating roof 501 is floated on the storage liquid 20. The pontoon type floating roof 501 has a pontoon 506 formed on the outer periphery of the floating roof body. Further, a sealing device (not shown) is appropriately formed between the pontoon type floating roof 501 and the side plate 511.
In the event of a fire at a location where a fire has occurred such as the liquid surface 21 between the pontoon type floating roof 501 and the side plate 511 or a predetermined location in the vicinity thereof, the fire extinguisher from the extinguishing agent discharge device installed at the upper end of the side plate, etc. Is released. However, a part of the extinguishing agent falls on the pontoon 506 as shown by an arrow X1 in FIG. 5, flows on the pontoon 506 toward the inside of the floating roof, and accumulates on the deck 503, so that the fire can be quickly detected at the location where the fire occurs. There was an inconvenience that it did not reach (extinguishing agent did not easily accumulate at the location where the fire occurred).

  In addition, the storage liquid 20 blown up from between the pontoon type floating roof 501 and the side plate 511 in an emergency such as abnormal boiling or abnormal pressure rise falls on the pontoon 506 as shown by an arrow Y1 in FIG. 5 and floats on the pontoon 506. The inconvenience arises in that it flows toward the inside of the roof and accumulates on the deck 503, resulting in a decrease in buoyancy.

  The present invention has been made in view of the above points. The purpose of the present invention is to make the fire extinguisher quickly reach the place where the fire occurred, and the stored liquid blown up in an emergency is accumulated on the deck and has buoyancy. The purpose is to provide a floating roof for the storage tank that prevents the situation from deteriorating.

In order to solve the above-mentioned problem, the floating roof of the storage tank according to the invention described in claim 1 includes an outer peripheral rim plate on an outer peripheral portion of a floating roof main body, an inner peripheral rim plate formed at a predetermined interval on the inner peripheral rim plate, and the outer peripheral rim. A floating roof of a storage tank having a pontoon provided with a pontoon upper plate over which a plate and an inner peripheral rim plate are crossed , wherein the upper pontoon plate flows on the pontoon toward the inside of the floating roof, and Alternatively, it has an inclination for changing the flow direction of the stored liquid, and the inclination is formed so that the entire outer side is lower than the inner side, and has an overhanging part that protrudes upward from the inner peripheral part of the pontoon upper plate. It is characterized by.

According to a second aspect of the present invention, the floating roof of the storage tank includes an outer peripheral rim plate on the outer peripheral portion of the floating roof main body, an inner peripheral rim plate formed at a predetermined interval on the inner peripheral rim plate, the outer peripheral rim plate and the inner peripheral rim. A floating roof of a storage tank having a pontoon with a pontoon top plate over which the plate is passed, wherein the top plate of the pontoon flows a fire extinguishing agent and / or a storage liquid that flows on the pontoon toward the inside of the floating roof The slope has a slope that changes direction, the slope is formed so that the whole is lower on the outside than the inside, and has a projecting portion that projects upward from the inner periphery of the pontoon upper plate, and the floating roof is It is an internal floating roof of a floating roof type storage tank with a fixed roof.

The floating roof of the storage tank according to the invention of claim 1 is a floating roof of a storage tank having a pontoon on the outer peripheral portion of the floating roof body, and the upper plate of the pontoon flows on the pontoon toward the inside of the floating roof. The extinguishing agent and / or the storage liquid has an inclination to change the flow direction, and the inclination is formed so that the entire outer side is lower than the inner side, and projects upward from the inner periphery of the pontoon upper plate. Since it has an overhang | projection part, the flow direction of the extinguishing agent which tries to flow on the inside of a floating roof on a pontoon, or the stored liquid which blows up is changed so that it may face outward. For this reason, it can prevent that a fire extinguishing agent and the stored liquid which blew up flow toward the inner side of a floating roof, and accumulate on a deck. Furthermore, since the fire extinguisher can flow outward as described above while flowing substantially along the circumferential direction of the internal floating roof on the pontoon, the fire extinguisher can quickly reach the fire occurrence site. As described above, in the floating roof of the storage tank according to the present invention, the fire extinguisher reaches the fire occurrence point quickly, and the stored liquid blown up in an emergency such as abnormal boiling or abnormal pressure increase accumulates on the deck and the buoyancy decreases. The situation can be prevented.
Furthermore, since it has the overhang | projection part which protruded upwards from the inner peripheral part of the said pontoon upper board, the flow direction of the extinguishing agent which flows on a pontoon, or the stored liquid blown up at the time of emergency can be changed more reliably. And thereby, it can prevent that a fire extinguisher and the stored liquid which blew up flow toward the inner side of a floating roof, and can prevent more reliably collecting on a deck.

Usually, the top surface of the pontoon is formed to be horizontal or lower than the outside so that rain flowing on the pontoon flows to the deck side while preventing it from flowing into the storage liquid. However, the invention according to claim 2 has the effects of the invention according to claim 1, and the floating roof is an internal floating roof of a floating roof storage tank with a fixed roof, so that it is possible to make a pontoon without considering rain. The upper surface of the substrate can be formed so as to have an inclination that the outside is lowered. For this reason, the floating roof which concerns on this invention can be formed easily, without forming a rain prevention apparatus etc.

  An embodiment of the present invention will be described with reference to the drawings. In the drawings, the same, corresponding, and generic items will be described with the same reference numerals. The present invention is not limited to the following embodiments. It goes without saying that changes (for example, changes in the shape of each member, etc.) can be added to the embodiments without departing from the gist of the present invention. It goes without saying that the constituent elements of the embodiment can be omitted without departing from the gist of the present invention.

  The floating roof of the storage tank according to the present embodiment is a floating roof of a storage tank having a pontoon on the outer peripheral portion of the floating roof body, and the upper surface of the pontoon is extinguished so as to flow on the pontoon toward the inside of the floating roof. It has a slope that changes the flow direction of the agent and / or storage liquid, and the slope is formed so that the outside is lower than the inside. The pontoon has an overhanging portion that projects upward. Each member is formed of metal or the like, and each member is joined to another member by welding or the like.

An example of this embodiment will be described in detail with reference to FIGS. In the figure, some of the hatching of the cross section is omitted. In addition, although embodiment of this invention details the example of the floating roof type storage tank with a fixed roof, rainwater countermeasures (illustration omitted), for example, providing a rainproof board with good performance between a side plate and a floating roof, If a roof drain that guides rainwater falling between the side plate and the floating roof with a gutter or the like and discharges it outside the storage tank is provided, it can be applied to a floating roof storage tank without a fixed roof.
When the floating roof is the internal floating roof 1 of the floating roof storage tank with a fixed roof as in the embodiment, the upper surface of the pontoon is inclined so that the outer side becomes lower without considering rain. A floating roof according to the invention can be formed.

  As shown in FIG. 1, a floating roof storage tank 10 with a fixed roof includes a plate-like (disc-like here) bottom plate 12 formed on a foundation (not shown), and a cylinder-like (cylindrical here) formed on the bottom plate 12. A side plate 11 and a roof 13 that covers the side plate 11. Further, the floating roof storage tank 10 with a fixed roof stores a storage liquid 20 such as a petroleum product that easily generates highly flammable vapor. The floating roof storage tank 10 with a fixed roof has an internal floating roof 1 floated on a storage liquid 20. The storage liquid 20 is a liquid fuel such as a petroleum product. Moreover, as shown in FIG. 3, the floating roof storage tank 10 with a fixed roof has the extinguishing agent discharge | release apparatus 15 in the side plate upper part (for example, the upper end part of the side plate 11). In the event of a fire, this extinguishing agent discharge device 15 releases the extinguishing agent. The floating roof storage tank 10 with a fixed roof appropriately includes a sealing device (not shown) formed between the internal floating roof 1 and the side plate 11.

As shown in FIGS. 1 to 4, the internal floating roof 1 is a pontoon type floating roof having a pontoon 6 on the outer peripheral portion of the internal floating roof body, and is annular (closed) so as to surround the deck 3. It has an internal cavity pontoon 6 formed in an annular shape in this embodiment. Here, the deck 3 is a plate-like (especially disk-like) single deck constituted by a portion excluding the outer peripheral portion of the plate-like member 2. However, the deck 3 is a single deck or a double deck having another configuration. May be.
For example, as shown in FIGS. 1 to 4, the pontoon 6 has a cylindrical shape formed on the outer periphery of the plate-like member 2 and the outer periphery (edge) of the outer periphery of the plate-like member 2 (here, Cylindrical outer peripheral rim plate 4 and a cylinder formed in parallel to the outer peripheral rim plate 4 (here, concentrically) and inside the outer peripheral portion of the plate-like member 2 with a predetermined distance from the outer peripheral rim plate 4 (Here cylindrical) inner peripheral rim plate 5, annular (here circular) pontoon upper plate 7 that bridges outer rim plate 4 and inner peripheral rim plate 5, and inner periphery of this pontoon upper plate 7 And a tubular (here, cylindrical) overhang portion 8 formed in the portion. In this case, the bottom plate of the pontoon 6 is constituted by the outer peripheral portion of the plate-like member 2, but the bottom plate of the pontoon 6 may be formed by a plate-like member different from the plate-like member 2. That is, the pontoon 6 may be formed separately from the deck 3 and joined to the deck 3 instead of using the plate-like member 2. At this time, the deck 3 may be joined midway in the vertical direction of the inner peripheral rim plate 5. Further, the internal floating roof 1 appropriately includes a buoyancy increasing portion (not shown) that increases the buoyancy of the internal floating roof 1.

  As shown in FIGS. 1, 2, and 4, the upper surface 7 a of the pontoon 6 (the surface of the pontoon upper plate 7) is a fire extinguishing agent and / or a storage liquid that tends to flow on the pontoon 6 toward the inside of the internal floating roof 1. Twenty slopes that change the direction of flow. Further, this inclination is formed so that the outer side (the outer peripheral rim plate 4 side) is lower than the inner side (the inner peripheral rim plate 5 side). The angle and area of the inclination are determined so as to change the flow direction of the extinguishing agent and / or the storage liquid 20 that flows toward the inside of the internal floating roof 1 on the pontoon 6, and the upper surface 7 a of the pontoon 6 Inclination that is lower on the outside is formed. For example, the inclination is formed by inclining the upper surface 7a so that the outside is lower than the inside. This inclination is formed so as to gradually decrease from the inside toward the outside in a direction substantially perpendicular to the circumferential direction of the pontoon 6 over the entire upper surface 7a of the pontoon 6. Accordingly, the flow direction of the extinguishing agent and / or the storage liquid 20 can be changed wherever the extinguishing agent and / or the storage liquid 20 falls on the pontoon 6, so that the extinguishing agent and / or the storage liquid 20 flows to the deck 3. It can be prevented more reliably. For example, as shown in FIGS. 1, 2, and 4, the inclination is caused by passing the annular pontoon upper plate 7 (here, the upper surface plate) with the outer peripheral rim plate 4 lower than the inner peripheral rim plate 5. Form. In addition, this inclination is formed, for example, by placing the outer rim plate 4 and the inner rim plate 5 at the same height and passing over the pontoon upper plate 7 (the inside may be hollow) having a substantially triangular cross section. You may do it.

  As shown in FIGS. 1, 2, and 4, the projecting portion 8 projects upward and is formed on the upper surface 7 a of the pontoon 6, that is, on the pontoon upper plate 7. For example, the protruding portion 8 is formed on the inner peripheral edge of the pontoon 6 as shown in FIGS. 1, 2, and 4. That is, the overhanging portion 8 corresponds to the inner peripheral rim plate 5 of the pontoon 6 and is formed on the pontoon upper plate 7 so as to extend the inner peripheral rim plate 5. As shown in FIGS. 1, 2, and 4, the overhanging portion 8 is a damming portion that dams the fire extinguishing agent and the stored liquid so that it does not flow inside the floating roof (on the deck 3). It is a dam plate. The overhanging portion 8 may be an extension of the inner peripheral rim plate 5 upward. In addition, this overhang | projection part 8 should just be provided in the inner peripheral part (edge on the inner peripheral side or its vicinity) of the pontoon 6, for example. The overhanging portion 8 may be a position where the extinguishing agent flowing on the pontoon 6 (or in the air on the pontoon 6) and the flowing direction of the stored liquid that has been blown up can be changed.

  A part of the fire extinguisher released by the fire extinguishing agent releasing device 15 falls down along the side plate 11, the other part falls on the pontoon 6, and the inside of the internal floating roof 1 on the pontoon 6 (on the upper surface 7 a). It tends to flow toward (inner rim plate 5 side). However, the upper surface 7a of the pontoon 6 has a slope that changes the flow direction of the fire extinguishing agent that flows on the pontoon 6 toward the inside of the internal floating roof 1, so that the outside is lower than the inside. Since it is formed, the flow direction of the extinguishing agent flowing on the pontoon 6 is changed so as to face the outer side (the outer peripheral rim plate 4 side), so that the extinguishing agent is substantially along the circumferential direction of the internal floating roof 1 on the pontoon 6. It flows outward while flowing. That is, the fire extinguisher flows as shown by the arrows in FIGS. 2 and 3, can reach a position far from the fire extinguisher discharge device 15, and can further fall to the liquid level 21 at a far position. For this reason, it is possible to quickly reach the fire occurrence point Z away from the extinguishing agent releasing device 15 (see the broken line arrow in FIG. 3). Further, it is possible to prevent the fire extinguishing agent from flowing on the pontoon 6 toward the inside of the internal floating roof 1 and short-passing on the deck 3.

  Further, when the storage liquid 20 blows up from the liquid surface 21 between the side plate 11 and the internal floating roof 1 in an emergency such as abnormal boiling or abnormal pressure increase, at least a part of the storage liquid 20 falls on the pontoon 6. The pontoon 6 tends to flow toward the inside of the internal floating roof 1. However, the upper surface 7a of the pontoon 6 has a slope that changes the flow direction of the fire extinguishing agent that flows on the pontoon 6 toward the inside of the internal floating roof 1, so that the outside is lower than the inside. Since it was formed, the flowing direction of the stock solution 20 blown up on the pontoon 6 is changed to face outward (see arrow R in FIG. 4). For this reason, the sprayed storage liquid 20 can return to the original, and the sprayed storage liquid 20 can be prevented from proceeding toward the inside of the floating roof and accumulating on the deck 3.

  From the above, the internal floating roof 1 allows the fire extinguishing agent to quickly reach the fire occurrence point Z. Further, the internal floating roof 1 can prevent the storage liquid 20 blown up in an emergency from collecting on the deck 3 and reducing the buoyancy.

  Moreover, since the pontoon 6 has the overhang | projection part 8 projected upwards, depending on the momentum of the extinguishing agent and the strength of the blowing up of the storage liquid 20 at the time of emergency, the pontoon 6 is in the air on the pontoon 6. ) A fire extinguishing agent that tends to flow toward the inside of the internal floating roof 1 and the stored liquid 20 that has blown up can be dammed, and the flow direction of these can be changed more reliably. This is particularly effective when the extinguishing agent has a strong momentum or when the stock solution 20 is blown up in an emergency. As a result, the extinguishing agent or the stored liquid that has blown up can be prevented from flowing on the pontoon 6 or in the air toward the inside of the internal floating roof 1, and can be more reliably prevented from accumulating on the deck 3. . Since the overhanging portion 8 projects upward, it is possible to prevent a fire extinguisher with a strong release momentum from flowing toward the inside of the internal floating roof 1 and to make a short pass. Depending on the momentum of the extinguishing agent, The flow direction can be changed more appropriately so as to substantially follow the circumferential direction of the internal floating roof 1, and the fire extinguisher flows over the pontoon 6 farther and reaches the fire occurrence point (see Z in FIG. 3) more reliably. Is also possible. Moreover, it can prevent more reliably that this storage liquid 20 flows toward the inner side of the internal floating roof 1 also with respect to the storage liquid 20 which blown up strongly at the time of emergency.

  As described above, the floating roof of the storage tank according to this embodiment can be widely applied to a pontoon type floating roof, and further, a pan type floating roof with a fixed roof (pan deck type floating roof) is modified to a pontoon type floating roof. In this case, since the floating roof structure according to the present invention can be adopted, it can be applied to a wide range of industries.

It is a figure which shows the one part schematic cross section of an example of an internal floating roof of a floating roof type storage tank with a fixed roof. It is the schematic enlarged view which made a part of an example of the internal floating roof of a floating roof storage tank with a fixed roof a cross section. It is the schematic plan view of the inside which abbreviate | omitted the fixed roof of an example of the internal floating roof of a floating roof type storage tank with a fixed roof. It is a general | schematic expanded sectional view of a part of an example of an internal floating roof of a floating roof type storage tank with a fixed roof. It is explanatory drawing for demonstrating the pontoon type floating roof of the conventional storage tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal floating roof 2 Plate-shaped member 3 Deck 4 Outer periphery rim plate 5 Inner periphery rim plate 6 Pontoon 7 Pontoon upper plate 8 Overhang | projection part 10 Floating roof storage tank 11 with a fixed roof Side plate 12 Bottom plate 13 Roof 15 Fire extinguisher discharge | release apparatus 20 Storage Liquid 21 Liquid level

Claims (2)

A floating tank having a pontoon provided with an outer peripheral rim plate on the outer peripheral portion of the floating roof body, an inner peripheral rim plate formed at a predetermined interval on the inner periphery thereof, and a pontoon upper plate over which the outer peripheral rim plate and the inner peripheral rim plate are bridged. The top plate of the pontoon has a slope that changes a flow direction of a fire extinguishing agent and / or a storage liquid that tends to flow on the pontoon toward the inside of the floating roof, and the slope is entirely from the inside. A floating roof of the storage tank, the outer roof of the pontoon upper plate being extended upwardly from the inner peripheral portion of the pontoon upper plate . A floating tank having a pontoon provided with an outer peripheral rim plate on the outer peripheral portion of the floating roof body, an inner peripheral rim plate formed at a predetermined interval on the inner periphery thereof, and a pontoon upper plate over which the outer peripheral rim plate and the inner peripheral rim plate are bridged. The top plate of the pontoon has a slope that changes a flow direction of a fire extinguishing agent and / or a storage liquid that tends to flow on the pontoon toward the inside of the floating roof, and the slope is entirely from the inside. Is formed so that the outside is lowered, and has an overhanging portion that projects upward from the inner peripheral portion of the pontoon upper plate, and the floating roof is an internal floating roof of a floating roof storage tank with a fixed roof The floating roof of the storage tank according to claim 1.

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