JP2571898Y2 - Suspension structure such as walkway for inspection work inside low temperature tank - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for suspending a suspended structure from a walkway or a similar roof suspended from a roof of a low-temperature tank and used for internal inspection work. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspended structure such as a walkway for inspection work inside a low-temperature tank, which reduces conduction and eliminates stress due to thermal contraction.

[0002]

2. Description of the Related Art In general, a low-temperature tank 30 for storing a low-temperature liquid such as LPG, LNG or the like is, as shown in FIG. Is buried in the ground, and a dome-shaped roof 32 is provided so as to cover an upper portion of the tank body opened to the ground. The roof 32 is composed of a roof bone made of H-shaped steel or the like spanned in a radial direction and a circumferential direction in order to support the entire roof at the tank body opening, and a roof plate stretched on the surface of the roof bone. . For the roof bone and the roof plate, a steel material containing 9% Ni is used. The temperature of the tank 31 is, for example, LNG.
A low-temperature storage liquid composed of a low-temperature liquefied gas at -162 ° C. is stored as shown in FIG.

On the other hand, on the roof 32, a structure 37 such as a walkway 36 used for an internal inspection work is provided with a liquid storage surface S from the roof 32.
Is provided to be suspended above. The suspension structure 37 such as the internal inspection work corridor 36 is used at room temperature during the internal inspection work, has sufficient strength, and is stably supported by the roof 32. Must have been. Therefore, a conventional support structure of the suspension structure 37 is to fix a lower end of a steel plate to a roof bone such as the above-mentioned H-shaped steel and to suspend the suspension plate. And a suspension structure 37 is attached thereto.

[0004]

By the way, the temperature of the liquid storage is -162 ° C. in the case of LNG, and the temperature difference is large because the external temperature is at or around room temperature. This temperature difference is blocked by the atmospheric gas inside the roof,
In the suspension structure, a steel plate serving as a suspension column has one end fixed directly to the roof bone and the other end suspended from the liquid storage surface. Therefore, heat conduction from the suspended structure and the suspended column facing the liquid storage surface to the roof bone is large. Cold heat is transmitted to the shingle via the suspension columns and the roof bones. as a result,
The shingle cools and ice sticks to the shingle surface. It is not preferable for the roof shingle to transmit the cold heat of the liquid to the roof shingle, and furthermore, the cold storage of the low-temperature tank is impaired, and the safety is reduced.

In the conventional suspension structure, the roof bone and the suspension column or the suspension column and the suspension structure are fixed to each other. That is, the suspension structure is a rigid structure. Such a rigid structure is sufficient for use at room temperature, but when a low-temperature liquid is supplied and the temperature near the liquid surface reaches -162 ° C, each component member undergoes significant thermal contraction. Stress is generated due to heat shrinkage, which may lead to destruction of a roof or the like, which is dangerous.

Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a suspension structure such as a walkway for inspecting the inside of a low-temperature tank, which reduces heat conduction to a roof and eliminates stress caused by heat shrinkage.

[0007]

The present invention in order to achieve the above object, there is provided a means for solving] in structure suspending the cold liquid inspection for corridor or the like from the roof inside of the tank to be housed in the tank, the corridor like hanging Attach a relatively small bolt with a small cross section vertically to each roof bone of the located tank roof
At the same time, screw a nut on this bolt to adjust the engagement height.
The combined pin member each provided, on the other hand, for the inspection
The support plate for hanging and supporting the corridor
Larger than the nut diameter.
And the above pin members are respectively inserted into the circular holes of the support plate.
Insert the bolt and screw the nut onto the bolt
The support plate is suspended by welding .

[0008]

With the above construction, even if the support plate and the inspection work corridor suspended and supported by the support plate are cooled to the low-temperature liquid temperature, the pin member has a relatively small cross-sectional area. Less cold heat is transmitted to the roof bone through the member. Therefore, conduction of cold heat to the roof is prevented.

Further, since the support plate is provided so as to be movable in the axial direction with respect to the pin member and in the radial direction within the range of the circular hole, the relative movement between the inspection work corridor and the like and the roof is possible. Even if the low-temperature liquid is supplied and the internal atmosphere temperature becomes low and the inspection work corridor or the like shrinks thermally, no stress is generated. Furthermore, if the pin member is
The nuts are screwed together to support
The engagement height of the holding plate can be adjusted.
To prevent stress from being concentrated on the
Wear.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

The suspension structure according to the present invention is used for the low-temperature tank 30 shown in FIG. As described in the conventional example, the low-temperature tank 30 includes a concrete tank 31 having an open top and a bottomed cylindrical shape, and a dome-shaped roof 32 covering the tank upper part. The roof 32 is composed of a roof bone made of H-shaped steel or the like spanned in a radial direction and a circumferential direction, and a roof plate stretched on the surface of the roof bone.

A number of suspension columns are suspended from the roof 32 at predetermined intervals along the periphery of the roof, and suspension structures 37 such as an internal inspection work corridor 36 are suspended on the suspension columns. Installed. That is, the internal inspection work corridor 36 is
2, it is suspended around the roof 36 so as to face the inner peripheral wall of the tank body 31 or is provided in an arc shape having a predetermined central angle. The suspension structure according to the present invention is used for the suspension structure of each suspension column.

The suspension structure according to the present invention is shown in detail in FIG.

As shown in FIG. 1, an H-shaped steel in which a web 1 extending in a strip shape and a strip-shaped flange 2 orthogonal to both short-axis sides of the web 1 are integrated, the flanges 2 are arranged vertically. It is provided and forms the roof bone 3. A metal plate 4 that is in contact with the lower flange 2a is welded to the lower flange 2a. On the lower surface of the metal plate 4,
A bolt 5 having a predetermined length is attached by welding one end thereof. At the lower end of the bolt 5, a nut 6 has a predetermined height.
Is screwed, attached is and welded of. The bolt 5 has a smaller cross-sectional area than the cross-sectional area of the suspension column constituting the conventional suspension structure, and forms the pin member 7 together with the nut 6. The body of the nut 6 projects radially outward of the bolt 5 to form a step 8.
A disk 11 having a circular hole 10 at the center is placed on the step 8. The diameter of the circular hole 10 is formed sufficiently larger than the outer diameter of the bolt 5 and smaller than the outer diameter of the nut 6, and there is no portion in contact with the bolt 5 all around the circular hole. Therefore, the disk 11 is allowed to move in the axial direction and the radial direction of the bolt 5. nut
6 is formed to adjust the engagement height of the suspension structure 37.
After the bolt 5 is inserted into the circular hole 10, the nut 6
So that it is welded to the bolt 5 at a predetermined height.
It has become. A stainless steel pipe 12 having a predetermined diameter is welded to the lower surface of the disk 11 by contacting an upper end opening thereof. Furthermore, at the lower end of the pipe 12,
It is welded to the support member 13 that supports the suspended structure 37 such as the inspection work corridor 36. That is, the disk 11 constitutes the support plate 14 that supports the suspension structure 37 by engaging with the pin member 7 movably in the axial direction and movably in the radial direction.

Next, the operation of the embodiment will be described.

Although the pin member 7 is formed to have a relatively small cross-sectional area, the load received from the suspension structure 37 is in the axial direction, and therefore can sufficiently support the load.
Similarly, the pipe 12 can support the suspension structure 37.

Even if the support plate 14 and the inspection walkway 36 suspended and supported by the support plate 14 are cooled to the low-temperature liquid temperature, the pin member 7 is formed with a relatively small cross-sectional area. The amount of cold transmitted to the roof bone 3 via the member 7 is small. Further, since the surface area of the pin member 7 itself is small, the degree of cooling of the pin member 7 to the atmosphere in the low-temperature tank 30 is small. Therefore, conduction of cold heat to the roof 32 is prevented.

Further, since the support plate 14 is provided so as to be movable in the axial direction and in the radial direction with respect to the pin member 7, the relative movement between the inspection work corridor 36 and the roof 32 is allowed. You. Therefore, even if the low-temperature liquid is injected and the ambient temperature near the liquid level in the low-temperature tank 30 becomes low, and the suspension structure 37 such as the inspection work corridor thermally contracts, the support plate 14 Move relative to Even if the positional relationship between the support plate 14 and the pin member 7 changes due to the relative movement, no stress is generated because the load that the pin member 7 receives from the suspension structure 37 is in the axial direction.

Next, another embodiment of the present invention will be described.

In the suspension structure shown in FIG. 2, a metal plate 4 which is in contact with the lower surface of the roof bone 3 is welded to the lower flange 2a, as in the case of FIG. A bolt 5 of a predetermined length is attached to the lower surface by welding one end thereof, and a nut 6 is screwed and welded to a lower end of the bolt 5. In this embodiment, a step 8 formed by the body of the nut 6 is formed.
Is a heat insulating member 9 formed of a heat insulating material in a ring shape.
Are mounted with bolts 5 inserted. The disk 11 of the embodiment is placed on the heat insulating member 9. As in the case of FIG. 1, a stainless steel pipe 12 having a predetermined diameter is welded to the lower surface of the disk 11 by contacting the upper end opening.

In this embodiment, since the heat insulating member 9 is interposed between the pin member 7 and the support plate 14, the inspection work corridor suspended and supported by the support plate 14 and the support plate 14. Even if 36 and the like are cooled to the low temperature liquid temperature, the cold heat is not conducted to the pin member 7.
For this reason, the effect of preventing thermal conduction shown in the above embodiment is further enhanced.

The suspension structure shown in FIG. 3 is similar to FIGS. 1 and 2 in that a metal plate 4 is welded to a lower flange 2a of a roof bone 3 and bolts 5 are attached to the lower surface of the metal plate 4. Is attached by welding one end thereof, and a nut 6 is screwed to a lower end of the bolt 5 and attached by welding. The difference from FIG. 2 is that a heat insulating member 9 formed by forming a heat insulating material in a ring shape having an annular groove 15 around the body is inserted into the bolt 7 through a step 8 formed by the body of the nut 6. That is, it is placed. Further, the disk 11 constituting the support plate 14 is arranged so that the circular hole 10 and the groove 15 of the heat insulating member 9 are loosely fitted to each other. In this embodiment, the support plate 14 is
The pin member 7 and the support plate 14
Since the heat insulating member 9 is also interposed in the radial gap between
Even if the pin member 7 and the support plate 14 move relative to each other due to thermal shrinkage, they do not come into contact with each other. Therefore, the heat insulating effect is not impaired by the contact between the pin member 7 and the support plate 14.

In the above three embodiments, the pin member 7 is constituted by a bolt and a nut.
Needless to say, it is sufficient to use a member having a small cross-sectional area enough to suspend and support 7 and reduce heat conduction.

Some of the low-temperature tanks 30 have cooling equipment. In this case, the tank body 31 and the roof 32 are provided on the inner side thereof with a cold insulator layer 34 for shutting off heat transfer to the outside and keeping the stored liquid cool. Cool insulation layer 34
Further, a stainless steel membrane 35 covering and sealing the stainless steel 35 is stretched inside. These tank bodies 3
1 and the cooling material layer 34 of the roof 32 and the membrane 35
Are joined at the periphery of the roof 32 so as to have a cooling property and a sealing property over the entire tank. A suspended structure 37 such as an inspection work corridor 36 is also attached to the low-temperature tank 30 having such cold insulation equipment. Also in this case, heat conduction can be suppressed by using the pin member 7 and the support plate 14 for the suspension structure.

[0025]

[Effects of the Invention] The present invention exhibits the following excellent effects.

(1) Since the heat conduction to the roof is small, the coolness of the low-temperature tank is improved.

(2) Since no excessive stress is generated due to heat shrinkage, the safety of the low-temperature tank is improved.

[Brief description of the drawings]

FIG. 1 is a detailed sectional view showing an embodiment of the present invention.

FIG. 2 is a detailed sectional view showing another embodiment of the present invention.

FIG. 3 is a detailed sectional view showing another embodiment of the present invention.

FIG. 4 is a side sectional view of a low-temperature tank having an inspection work corridor.

[Explanation of symbols]

 3 Roof bone 7 Pin member 9 Insulation member 14 Support plate 36 Walkway for inspection work

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Naito 3-2-16-1 Toyosu, Koto-ku, Tokyo Ishikawa-Shimaharima Heavy Industries, Ltd. Toyosu General Office (72) Inventor Noriko Kobayashi 3-Toyosu Toyosu, Koto-ku, Tokyo No. 2-16 Ishikawajima-Harima Heavy Industries, Ltd.Toyosu Sogo Office (72) Inventor Shunichi Honma 3-16 Toyosu, Koto-ku, Tokyo Ishikawa Shima-Harima Heavy Industries Toyosu Sogo Office (56) 63-118498 (JP, U) 1-91194 (JP, U) JP-B 54-43726 (JP, B2) (58) Fields investigated (Int. Cl. ⁶ , DB name) E04G 3 / 14 E04G 1/36 F17C 13/00

Claims (1)

(57) [Scope of request for utility model registration] In a structure for suspending an inspection work corridor or the like from the inside of a tank containing a low-temperature liquid into the tank, each roof bone of the tank roof located in the suspended corridor or the like has a relatively small cross-sectional area. Install small bolts vertically
At the same time, screw a nut on the bolt to adjust the engagement height
The pin member each provided, on the other hand, the inspection work step
The support plate for hanging and supporting the corridor
Form a circular hole with a diameter larger than the diameter of the nut
And insert the pin members into the circular holes of the support plate.
While inserting the bolt, screw the nut onto the bolt to melt it.
A hanging structure such as a walkway for inspection work inside a low-temperature tank, which is connected and joined and a support plate is hung .