JP2016055883A - Large tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large tank which inhibits deformation when hoisted and achieves improvement of the workability during hoisting operation.SOLUTION: A large tank includes: a cylindrical shell plate 2; a bottom plate 3 closing a lower end of a cylinder formed by the shell plate 2; a top plate 4 closing an upper end of the cylinder formed by the shell plate 2; a built-in balance 5 disposed in an internal space formed by the shell plate 2, the bottom plate 3, and the top plate 4; a reinforcement stay 6 which fixes the built-in balance 5 and the bottom plate 3; and a hoist metal fitting 7 provided in the built-in balance 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a large tank for storing a liquid, and particularly to a lifting structure for a large tank.

  For example, when a tank that stores liquid (contaminated water) is installed in a nuclear power plant, if the tank is placed in a radiation environment in the nuclear power plant, workers cannot stay for a long time, so large welding It is difficult to manufacture the mold tank at the installation site. For this reason, a method of assembling a small flange-type tank at the installation site and a method of transporting a large welded tank manufactured at another location and installing it at the installation site are conceivable.

  When transporting large tanks manufactured at other locations and installing them at the installation site, sea transport is mainly used, but “loading from a place (factory) where large tanks were manufactured to a multi-axis cart”, “from multi-axis carts” Lifting five times is required, such as “loading to a ship”, “loading from a ship to a multi-axle cart”, and “installation from a multi-axis cart to an installation location”.

  Here, as a method of installing a cylindrical giant structure, Patent Document 1 (Japanese Patent Laid-Open No. 9-287314) discloses a plurality of long rods that are radially arranged to form a roof skeleton and serve as a balance rod of a suspension balance mechanism. Suspension balance comprising a scale member, a roof body made of a sheet member covering the roof skeleton, and a crane suspension provided near the distal ends of the plurality of long members and connected to a crane via a wire A roof body with a function is used, and the roof body with a suspension balance function is installed at the upper end of a cylindrical giant structure manufactured in a factory, and in this state, the tubular giant structure is transported to an installation site, Installation of the cylindrical giant structure characterized in that, at the installation site, the tubular giant structure is lifted by a crane through the roof with the suspension balance function, and the tubular giant structure is installed at an installation position. Only methods have been disclosed (see claim 1).

JP-A-9-287314

  In Patent Document 1, a reactor containment vessel is taken as an example of a cylindrical giant structure to be installed. On the other hand, a large tank for storing liquid, particularly a large tank whose internal pressure is a hydrostatic head, has a thin-walled cylindrical structure and is a tank having no rigidity for suspension. For this reason, when a large tank is lifted and installed, the following problems occur depending on conditions.

  Firstly, in a conventional large tank, there is a possibility that the body plate and the bottom plate may be deformed due to the weight of the large tank when it is lifted.

  Secondly, conventional large tanks are lifted using a crane when they are lifted. However, since the lifting height including the balance of the large tank and the lifting wire is increased in addition to the overall height of the large tank, A crane with a long boom according to the height of the hook is required, and it becomes difficult to hang up.

  Thirdly, when the installation location of the large tank is a place where the worker cannot stay for a long time, it is difficult to adjust the suspension balance and to attach and remove the large tank and the suspension balance.

  Then, this invention makes it a subject to provide the large sized tank which suppresses the deformation | transformation at the time of lifting of a large sized tank, and improves the workability | operativity of suspension work.

  In order to solve such a problem, a large tank according to the present invention includes a cylindrical body plate, a bottom plate closing the lower end of the cylinder formed by the body plate, and an upper end of the cylinder formed by the body plate. A built-in balance disposed in an internal space formed by the body plate, the bottom plate, and the top plate, a reinforcing stay that fixes the built-in balance and the bottom plate, and the built-in balance And a hanging metal fitting provided on the head.

  ADVANTAGE OF THE INVENTION According to this invention, the deformation | transformation at the time of lifting of a large sized tank can be suppressed, and the large sized tank which can improve the workability | operativity of suspension work can be provided.

It is a cross-sectional schematic diagram of the large sized tank which concerns on this embodiment. It is a top view of a large sized tank in the state where a top plate was removed from a large sized tank concerning this embodiment. It is a top view of the large sized tank concerning this embodiment. It is a schematic diagram which shows the state which lifted the large sized tank which concerns on this embodiment with the crane. It is a cross-sectional schematic diagram of the large sized tank which concerns on a reference example. It is a schematic diagram which shows the state which lifted the large sized tank which concerns on a reference example with the crane.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings as appropriate. In each figure, common portions are denoted by the same reference numerals, and redundant description is omitted.

≪Large tank according to this embodiment≫
A large tank 1 according to the present embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic cross-sectional view of a large tank 1 according to this embodiment. FIG. 2 is a top view of the large tank 1 in a state where the top plate 4 is removed from the large tank 1 according to the present embodiment. FIG. 3 is a top view of the large tank 1 according to the present embodiment.

  As shown in FIG. 1, a large tank 1 according to the present embodiment includes a cylindrical body plate 2, a bottom plate 3 that closes a lower end of a cylinder formed by the body plate 2, and a cylinder formed by the body plate 2. And a top plate 4 that closes the upper end, and can store liquid (for example, contaminated water) inside. In the large tank 1 according to the present embodiment, the internal pressure is a hydrostatic head. In addition, the large sized tank 1 which concerns on this embodiment can be used as the welding type tank which connects steel materials (the trunk plate 2, the baseplate 3, the top plate 4) by welding. Incidentally, the size of the large tank 1 according to this embodiment is, for example, a substantially cylindrical structure having a diameter of 12 m and a height of 12 m, and stores 1,000 tons or more of liquid (contaminated water) per unit. A large tank with a possible volume.

  As shown in FIG. 3, the top plate 4 is supported by stays 4a provided radially. Although not shown, an opening for providing a pipe for allowing liquid (contaminated water) to flow into or out of the large tank 1 is formed in a substantially central portion of the top plate 4. Although not shown, the large tank 1 is provided with elevating means such as traps and stairs on the outer side surface thereof, so that workers can install large tanks 1 during construction of pipes and various inspections and maintenance. It is possible to work on (top plate 4).

  As shown in FIG. 1, the large tank 1 according to the present embodiment further includes a built-in balance 5, a reinforcing stay 6, and a hanging bracket 7.

  As shown in FIG. 1, the built-in balance 5 is disposed in the horizontal direction inside the large tank 1 (internal space formed by the trunk plate 2, the bottom plate 3, and the top plate 4), and the hanging wire 11 is disposed on the upper side. Suspension fittings 7 are provided to pass through. Both ends of the built-in balance 5 are fixed to the inner wall surface of the body plate 2 by welding or the like (fixing portion 5a). As shown in FIG. 2, the built-in balance 5 has two linear steel materials arranged in parallel, and two more linear steel materials in parallel so as to be orthogonal to the two steel materials arranged in parallel. It is arranged in a so-called “well” shape. As seen from above the large tank 1, the hanging metal fittings 7 are arranged at four locations at the intersections of the linear steel materials of the built-in balance 5.

  As shown in FIG. 1, the reinforcing stay 6 is arranged in the vertical direction inside the large tank 1. The lower end of the reinforcing stay 6 is fixed to the inner wall surface of the bottom plate 3 by welding or the like (fixing portion 6a). As shown in FIG. 2, the upper portion of the reinforcing stay 6 is fixed to the built-in balance 5 by welding or the like (fixing portion 6b). That is, the built-in balance 5 and the bottom plate 3 are fixed by the reinforcing stay 6 so as to be integrated. As shown in FIG. 2, four reinforcing stays 6 are arranged at the intersections of the linear steel members of the built-in balance 5 when viewed from above the large tank 1. That is, as seen from the side surface of the large tank 1, the hanging metal fitting 7 is disposed above the reinforcing stay 6.

  As shown in FIG. 2, the hanging metal fitting 7 is provided above the built-in balance 5 and above the reinforcing stay 6. Further, as shown in FIG. 3, the hanging metal fitting 7 projects from the opening 4 b of the top plate 4. As shown in FIGS. 2 and 3, the four hanging brackets 7 are arranged along the orthogonal center line indicated by the alternate long and short dash line.

  As described above, the built-in balance 5 having the hanging metal fitting 7 on the upper side is fixed to the inner wall surface of the bottom plate 3 at eight locations (fixed portion 5a), and the inner wall surface of the bottom plate 3 via the reinforcing stay 6 and four locations. (Fixed portions 6a and 6b). With such a configuration, as shown in FIG. 1, the large tank 1 according to the present embodiment can be lifted by the crane hook 10 through the suspension wire 7 through the suspension wire 11.

≪Large tank according to reference example≫
Here, a large tank 1C according to a reference example will be described with reference to FIG. FIG. 5 is a schematic cross-sectional view of a large tank 1C according to a reference example.

  As shown in FIG. 5, a large tank 1 </ b> C according to a reference example includes a cylindrical body plate 2, a bottom plate 3 that closes a lower end of a cylinder formed by the body plate 2, and an upper end of a cylinder formed by the body plate 2. It is common with the large tank 1 (refer FIG. 1) which concerns on the point which is equipped with the top plate 4 which closes and can store a liquid (for example, contaminated water) inside.

  On the other hand, the large tank 1C according to the reference example is different from the large tank 1 according to the present embodiment (see FIG. 1) in that a hanging metal fitting 8 is provided on the outer side surface of the body plate 2.

  With such a configuration, the large tank 1C according to the reference example is hung with the crane hook 10 by using the suspension balance 9 and the suspension wires 11 and 12 by hanging the suspension wire 12 from the suspension balance 9 on the suspension fitting 8 vertically. Can be done.

≪Action and effect of large tank according to this embodiment≫
Next, the operation and effect of the large tank 1 according to this embodiment will be described in comparison with the large tank 1C according to the reference example.

  In general, a large tank whose internal pressure is a hydrostatic head has a thin cylindrical structure, and is a tank having no rigidity for suspension. In addition, the large tank has a large weight and a large weight.

  For this reason, as shown in FIG. 5, the large tank 1C according to the reference example suspends the hanging metal fitting 8 provided on the thin body plate 2 with the suspension balance 9, so that the large tank 1C is suspended when the large tank 1C is suspended. A moment M that the body plate 2 tends to deform due to its own weight acts, and a stress σ is generated. When the stress σ exceeds the material strength of the body plate 2, the body plate 2 is deformed. For this reason, in the large tank 1C according to the reference example, it is necessary to make the body plate 2 thick or to reinforce the body plate 2 so that the body plate 2 is not deformed. Further, the large tank 1C according to the reference example may increase in weight.

  On the other hand, as shown in FIGS. 1 to 3, the large tank 1 according to the present embodiment is provided with a reinforcing stay 6 between the built-in balance 5 and the bottom plate 3 to connect the built-in balance 5 and the bottom plate 3. The large tank 1 is hung by a hanging metal fitting 7 that is integrated and provided on the built-in balance 5. As a result, the moment M at which the body plate 2 tends to deform is reduced, and the stress σ is also reduced. That is, the large tank 1 according to the present embodiment can suppress deformation of the body plate 2 during lifting, as compared with the large tank 1C according to the reference example. For this reason, the large tank 1 which concerns on this embodiment does not need to thicken the thickness of the trunk | drum 2 more than necessary, or to reinforce the trunk | drum 2. Further, the large tank 1 according to the present embodiment can reduce an increase in weight.

  FIG. 4 is a schematic diagram illustrating a state where the large tank 1 according to the present embodiment is lifted by the crane 21. FIG. 6 is a schematic diagram illustrating a state where the large tank 1 </ b> C according to the reference example is lifted by the crane 22.

  As shown in FIG. 6, the large tank 1 </ b> C according to the reference example is lifted by a crane hook 10 using a suspension balance 9 and suspension wires 11 and 12. For this reason, the suspending height H2 (the height from the upper end of the trunk plate 2 to the crane hook 10) is increased, and the lifting height is increased, so that the operation time is also increased. Further, since the boom length L2 of the crane 22 for lifting the large tank 1C is also increased, a larger crane 22 is required. Further, the work is performed while taking into account the deformation of the body plate 2.

  On the other hand, as shown in FIG. 4, the large tank 1 according to the present embodiment incorporates a built-in balance 5 having a suspension bracket 7 in the large tank 1, thereby providing another suspension balance at the time of transportation, loading and installation. Do not need. Further, since the suspension height H1 (the height from the upper end of the trunk plate 2 to the crane hook 10) can be shortened, the boom length L1 of the crane 21 for lifting the large tank 1 is also suppressed. Can do.

  That is, the suspension height H1 of the large tank 1 according to the present embodiment can be made shorter than the suspension height H2 of the large tank 1C according to the reference example. Thereby, the boom length L1 of the crane 21 that lifts the large tank 1 according to the present embodiment may be shorter than the boom length L2 of the crane 22 that lifts the large tank 1C according to the reference example. That is, the large tank 1 according to this embodiment can be lifted by the crane 21 that is smaller than the crane 22 that lifts the large tank 1C according to the reference example.

  Further, as shown in FIG. 6, in the large tank 1 </ b> C according to the reference example, the suspension fitting 8 is provided on the outer side surface of the trunk plate 2, so that when an operator hangs the suspension wire 12 on the suspension fitting 8, A work vehicle (lift vehicle) 23 is required.

  On the other hand, in the large tank 1 according to the present embodiment, as shown in FIG. 3, the suspension fitting 7 is provided so as to protrude from the top plate 4, so that an operator is provided on the outer side surface of the large tank 1. The maintenance wire (not shown) can be used to hang the suspension wire 11 on the suspension fitting 7 by being raised on the large tank 1 (top plate 4).

  That is, the large tank 1 according to the present embodiment can improve workability and shorten the working time as compared with the large tank 1C according to the reference example. Moreover, it is possible to work without using an additional vehicle such as an aerial work vehicle (lift vehicle) 23.

≪Modification≫
In addition, the large sized tank 1 which concerns on this embodiment is not limited to the structure of the said embodiment, A various change is possible within the range which does not deviate from the meaning of invention.

  The large tank 1 according to the present embodiment is described as a tank that stores liquid installed in a nuclear power plant, and particularly, a tank that stores contaminated water under a radiation environment in the nuclear power plant. However, it is not limited to this. Since the worker cannot stay for a long time, it can be widely applied to a large tank that is difficult to manufacture at the installation location.

  The shape of the built-in balance 5 has been described as a “well” character, but is not limited thereto. Further, the number of the reinforcing stays 6 and the number of the hanging metal fittings 7 are not limited.

DESCRIPTION OF SYMBOLS 1,1C Large tank 2 Body plate 3 Bottom plate 4 Top plate 4b Opening part 5 Built-in balance 5a Welding part 6 Reinforcement stay 6a, 6b Welding part 7, 8 Hanging bracket 9 Hanging balance 10 Crane hook 11, 12 Hanging wire 21,22 Crane 23 Aerial work platform H1, H2 Lifting height L1, L2 Boom length σ Stress M Moment

Claims (8)

A cylindrical body plate;
A bottom plate that closes a lower end of a cylinder formed by the body plate;
A top plate for closing the upper end of the cylinder formed by the body plate;
A built-in balance disposed in an internal space formed by the body plate, the bottom plate, and the top plate;
A reinforcing stay for fixing the built-in balance and the bottom plate;
A large-sized tank comprising a hanging metal fitting provided on the built-in balance. The hanging bracket is
The large tank according to claim 1, wherein the large tank is provided so as to protrude from an opening of the top plate. The built-in balance is
The large tank according to claim 1, wherein an end of the built-in balance is fixed to an inner wall surface of the body plate. The built-in balance is
Two straight steel materials are arranged in parallel, and two straight steel materials are arranged in parallel so as to be orthogonal to the two steel materials arranged in parallel,
The hanging bracket is
The large tank according to claim 1, wherein the large tank is provided at a position of an intersection of the linear steel materials. The reinforcing stay is
The large tank according to claim 4, wherein the large tank is provided at a position of an intersection of the linear steel materials of the built-in balance. The large tank according to claim 1, wherein when the liquid is stored in the large tank, the internal pressure of the large tank is a hydrostatic head. The large tank according to claim 1, wherein the large tank is a welded tank. The large tank according to claim 1, wherein the large tank is installed in a nuclear power plant.

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