JPS5954900A - Support structure of temperature regulated tank - Google Patents

Abstract

PURPOSE:To prevent the generation of thermal stress of the skirt-like support member of an LNG tank and a tank and facilitate precooling by covering the outer periphery of the skirt-like support member and the tank with a heat insulating material and arranging a fluid feed pipe for temperature regulation inside the heat insulating material. CONSTITUTION:A spherical LNG tank 1 is supported by a cylindrical skirt-like support member 2 at its equator section. The outer face of the tank 1 and the upper section 2a of the skirt-like support member 2 are covered by a heat insulating material 3, and multiple cooling pipes 5 as a fluid feed pipe for temperature regulation are arranged along the upper section 2a. Precooling is performed by circulating LNG, etc. through these cooling pipes 5, thus the temperature difference between the tank 1 and support member 2 is decreased and the total stress at these positions can be prevented from being generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support structure for a tank, and particularly to a temperature-adjustable tank support structure suitable for storing low-vortex liquefied scum and the like.

Conventionally, liquefied natural gas (hereinafter referred to as l'-LNGj) is used.

) In a carrier ship, there is a support structure for a spherical tank that stores LNG as shown in FIG. 3, and the skirt-like support part 2 is covered with a heat insulating material 3. ing.

Tank 1 and skirt-like support 1J' 2 iJ2,
In the case of an empty cargo with no LNG stored, it is equal to 7 manliness, so if cryogenic I/NG is newly loaded, the temperature change caused by this loading will cause tank 1 and the skirt support Excessive thermal stress is generated in the parts 4] and 2.

Therefore, in order to avoid damage to the tank 1 and the skirt-like support member 2 due to this thermal stress, before loading I and NG, spray LNG into the tank 1 little by little with the spray ν (Iso 4) inside the tank 1. -C, the tank 1 and the skirt-like support member 2 are gently precooled.

By this pre-cooling, LNG loading is carried out after cooling the tank l for 1 minute.
In the conventional tank support structure, the spray pipe 4 quickly transfers the tank to '-T'('a 7:1
2, the skirt-like support member 2 is not directly cooled 17,
Since heat is indirectly taken away by the cooling of the tank 1, the support part 2 of the frame 7-l is not cooled. Therefore, it takes a long time to pre-cool the entire tank 1. There is a problem that it takes.

Moreover, in the conventional tank support structure, if the temperature difference between the tank 1 and the skirt-shaped support part (A2) becomes large, excessive thermal stress will be generated, so in order to prevent this excessive thermal stress,
1 tank 1 according to the cooling rate of the skirt-like support member 2
The cooling rate must also be slowed down, thereby requiring a large amount of pre-cooling time in the middle.

Also, when storing high-temperature fluid cargo in a tank, this is to prevent excessive thermal stress from occurring.

A considerable amount of preheating must be performed, and in this case as well, there are almost the same problems as in the case of storing cryogenic fluid cargo as described in Section 6.

The present invention aims to solve these problems.
By directly cooling or heating the skirt-like support member during pre-cooling or pre-heating, the generation of thermal stress can be reduced.
The purpose of the present invention is to provide a temperature-adjustable tank support structure that can significantly reduce pre-cooling or pre-heating time.

Therefore, the humidity-adjustable tank support structure of the present invention includes a skirt-like support member that supports the outer periphery of the tank and a heat insulating material that covers the outer periphery of the tank. In order to prevent the occurrence of thermal stress due to the temperature difference between the support member and the support member, a fluid supply pipe for controlling the humidity of the support member is disposed inside the heat insulating material that covers the support member.

Hereinafter, an embodiment of the invention and a temperature-adjustable tank support structure (-) will be explained with reference to the drawings. FIG. 2 is an enlarged cross-sectional view showing the main part thereof in comparison with a part of FIG.
In FIG. 2, the same reference numerals as in FIG. 1 indicate substantially the same components.

As shown in FIG. 2, a spherical tank 1 is supported at its equator by a cylindrical skirt-like support member 2. As shown in FIG.

Therefore, the outer surface of the tank 1 and the -L portion 2a of the skirt-like support portion 2 are separated by the heat insulating material 3.

By the way, along the outer periphery of the upper part 221 of the skirt-like support part 2, a plurality of cooling pipes 5 are arranged as fluid supply pipes for controlling humidity.

The cooling pipe 5 is configured to circulate a low-concentration liquefied gas (for example, LNG) from a device (not shown).

With the above-mentioned configuration, pre-cooling before loading LNQ into the tank 1 is performed by cooling the inside of the tank 1 with the spray pipe 4 (see Figure 1) inside the tank 1, and at the same time, a low temperature is supplied to the cooling pipe 5. This is done by directly cooling the skirt support 2 by circulating liquefied gas. As a result, during pre-cooling, the tank 1 and the skirt-like support part 2 are cooled simultaneously, and the so-called 1 degree difference between them becomes negligible, so thermal stress (work) occurs due to the humidity difference. Minutes (・L-1j, jj
It will be stopped.

Note that by adjusting the number of cooling pipes 5, etc., the cooling speed of the tank 1 by the spray pipe 4 and the cooling pipe 5 can be adjusted.
The cooling rate of the skirt-like support J%' can be made almost equal to the cooling rate of the tee 2.

Further, when loading high temperature fluid cargo into the tank 1, high temperature fluid is flowed through the fluid supply pipe to directly preheat the scarf support member 2.

As detailed above, the uninvented humidity-adjustable tank support structure is provided with a heat insulating material that protects the outer periphery of the tank and the Nuka-1-aki support member that supports the outer periphery of the tank. In order to prevent the occurrence of thermal stress due to the temperature difference between the support member and the tank on the moon, the heat shield (
] It has a simple structure in which a fluid supply pipe that adjusts the temperature of the support member is installed inside the tank.
The skirt-like support member can be preset by iθ4 (or pre-preparation 8), thereby making the skirt-like support member (
While preventing the occurrence of thermal stress between A and the tank within 1 inch,
There is an advantage that precooling (or preheating) can be carried out rapidly, and this has the advantage that F (11 hours) (or preheating time) can be significantly shortened.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional view showing a conventional tank support structure, and FIG. 2 shows a main part of a temperature-adjustable tank support structure as an embodiment of the present invention in comparison with a part of FIG. 1. FIG. 1. Tank, 2. Skirt-shaped support member, 2a. 2 parts of skirt-shaped support member, 3. Heat insulation, 4. Spray vibe, 5. Cooling pipe as fluid supply layer. Agent Patent Attorney Yoshihiko Iinuma Figure 1 Figure 2 541--

Claims (1)

[Claims] In order to prevent the occurrence of thermal stress due to a humidity difference between the support member and the tank in the support portion, a skirt-like support member that supports the outer circumference of the tank and a heat insulating material that covers the outer circumference of the tank are provided. A one-degree adjustable tank support structure, characterized in that a fluid supply pipe is provided inside the heat insulating material that supports the support member to easily adjust the temperature of the support member.