JPS6019880A - How to build a double shell tank - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method of constructing a double shell tank.

Conventionally, when constructing double-shell cryogenic tanks for storing low-temperature liquids, only the inner tank was made of low-temperature materials, the outer tank was made of ordinary steel, and pressure tests were conducted only on the inner tank. However, in the event that low-temperature liquid leaks from the inner tank due to the action of an unexpected force such as an earthquake, there is a risk that the damage will expand because the outer tank cannot withstand the low temperature and liquid pressure. In order to do this, in recent years both the inner tank and the outer tank have been made of low-temperature materials, and even if the low-temperature liquid in the inner tank leaks, the outer tank can withstand the liquid pressure and has a structure that prevents the low-temperature liquid from leaking outside. is becoming required.

Conventionally, in order to construct such a double-shell tank, the method shown in Figure 1 (A
) to (E). That is, first, as shown in (A), the outer tank a was made of low-temperature material, and then a pressure test was performed by filling the outer tank with water as shown in (B), and then as shown in (C). After draining the water, as shown in (D>), create an inner tank C using low-temperature material inside the outer tank a, and then fill the inner tank C with a water bath as shown in (E) to make it resistant to pressure. After conducting the test, drain the water.

However, in the above conventional method J5, the production of the inner tank C cannot be started at all until the pressure test of the outer tank A is completed, resulting in poor work efficiency and the need to conduct the pressure test twice. This has the problem of increasing the number of man-hours and construction period, and also requires a large amount of water to conduct the pressure test twice.

The present invention has been made in view of these circumstances. By airtightly connecting the bottom of the outer tank and the outer periphery of the bottom of the inner tank with a waterproof plate, the outer tank and the inner tank can be constructed simultaneously using low-temperature materials. The purpose is to improve work efficiency and shorten construction time by making simultaneous pressure tests possible.

Embodiments of the present invention will be described below with reference to the drawings.

Ru.

When constructing a double-shell tank using low-temperature materials, Figures 2 to 5
As shown in the figure, an outer WJ 1 and an inner tank 2 are constructed in parallel. By constructing the outer tank 1 and the inner tank 2 at the same time in this way, related work can be carried out together, making it possible to perform the work efficiently. In the figure, 3 is the outer tank bottom plate, 4 is the outer tank side plate, 5 is the inner tank bottom plate, 6 is the inner tank side plate, 7 is the inner tank stand structure, 8
indicates the bottom cold insulation material.

Furthermore, the outer tank 1 and the inner tank 2 constructed as described above are connected airtight at the bottom. Figures 21 to 5 show examples, and Figures 2 and 3 show the case where a general steel waterproof plate 9.10 is used, and Figure 2 shows the same part on the outside of the inner tank bottom plate 5. A waterproof plate 9 is connected to the outer tank bottom plate 3 in an airtight manner by welding 13, and in FIG. There is. In this case, the prevention plates 9 and 10 are removed after the pressure test is completed. Figures 4 and 5 show waterproof board 1 made of low-temperature material.
1.12, and in this case, it can be used as is even after the pressure test is completed, and for this reason, the shape is such that it can absorb deformation due to temperature changes.

In the double shell tank configured in this way, No. 6.7
As shown in the figure, each of the water supply pipes 15.16 branched from the water supply pump 14 is connected separately to the outer tank 1 and the inner tank 2 via valves 17.18. In the diagram, 19 is the tank roof, 20
indicates water.

When constructing a double shell tank, as shown in Figures 2 to 5 above, the outer tank 1 and the inner tank 2 are assembled in parallel, and the outer tank 1 and the inner tank 2 are placed at the bottom position. waterproof board 9 or 10,
11. Connect hermetically by 12. Thereafter, as shown in FIG. 6, by closing the valve 11 and driving the water supply pump 14, water 20 is supplied to the inner tank 2 through the water supply pipe 16 and valve 18, and the pressure resistance test of the inner tank 2 is performed. Then, as shown in FIG. 7, the valve 18 is closed and the valve 17 is opened to supply water 20 into the outer tank 1 to perform a pressure resistance test of the outer tank 1.

After the pressure test is completed, drain all the water in the inner and outer tanks 1 and 2.
remove. Thereafter, if the waterproof plate is made of general steel as shown in FIG. 2.3 J', it is removed, and then work such as filling a cold insulating material between the outer tank side plate 4 and the inner tank side plate 6 is performed.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and various changes may be made to the airtight connection method using the waterproof plate, the water supply method, etc. without departing from the gist of the present invention.

According to the method for constructing a double shell tank of the present invention described above, the following excellent effects can be achieved.

(1) The outer and inner tanks were constructed using low-temperature materials in parallel, and the pressure resistance tests of the inner and outer tanks were conducted at the same time.
It is possible to significantly improve work efficiency and significantly shorten the construction period.

(II) The amount of water used in pressure tests can be significantly reduced.

(To) Since water does not get wet between the bottom of the inner tank and the bottom of the outer tank, it is possible to prevent moisture from entering the bottom cold insulation material.

00 Tank construction costs can be reduced.

[Brief explanation of the drawing]

Figure 1 (A) (B) (C) (D) (E> shows the conventional construction method of a double-shell tank using low-temperature materials according to the procedure.
The explanatory drawings, FIGS. 2 to 5 are explanatory drawings showing the construction method of the present invention and examples of drawing waterproof plates, and FIGS. 6 and 7 are explanatory drawings showing examples of pressure resistance tests. 1 is the outer tank, 2 is the inner tank, 8 is the bottom cold insulation material, 9, 10° 11
．． 12 is a waterproof plate, 13 is a welding, 14 is a water supply pump, 15
．． 16 indicates a water supply pipe, and 17.18 indicates a valve. Figure 6

Claims (1)

[Claims] 1) After constructing an outer tank and an inner tank in parallel using low-temperature materials and airtightly connecting the bottom of the outer tank and the outer circumference of the bottom of the inner tank to a waterproof plate, water is poured into the inside of the inner tank. A method for constructing a double-shell tank, comprising: supplying water to perform a pressure resistance test of the inner tank; and then supplying water to the inside of the outer tank to perform a pressure resistance test of the outer tank.