JPH08217190A - Explosion release structure for tank - Google Patents

Abstract

PURPOSE: To provide an explosion release structure for a tank, capable of controlling a position where a roof of the tank is bursted and a position where the bursted roof is blown off. CONSTITUTION: A stainless steel sheet 12 is welded to a portion of the periphery of a tank roof 4, and this stainless steel sheet 12 is welded to a stainless steel layer 11 formed by padding welding on a flange part 5a provided at the upper end of a tank side plate 3, thus sealing the tank roof 4. By this method, the strength of the stainless steel sheet portion is made lower to release explosion, while corrosion can be prevented by utilizing stainless steel. Further, a wire 13b for connecting the roof 4 to the side plate 3 is mounted on the opposite side of the explosion release portion of the roof 4, thereby controlling the movement of the roof in the case where the roof 4 is blown off by explosion. With this arrangement, the outflow of a stored liquid in the tank due to breakage of the whole tank, a welded part between the bottom plate and the side plate, etc., which is caused by explosion, can be prevented, whereby a secondary accident can be prevented from occurring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an explosive structure for a tank for storing a flammable liquid such as crude oil or volatile petroleum,
It is designed so that the moving direction of the roof, which may move during detonation, can be restricted.

[0002]

2. Description of the Related Art A tank for storing flammable liquids such as crude oil and volatile petroleum has a bottom plate 2 laid on a foundation 1 formed on the ground, as shown in FIGS. This bottom plate 2
A cone-shaped or dome-shaped roof 4 having a central portion projecting upward is stretched around the peripheral edge of the cylindrical side plate 3 established above, and is configured to store a combustible liquid such as crude oil inside. .

In a tank that stores this kind of flammable liquid, if the entire tank is destroyed, for example, when the internal pressure suddenly rises due to the effect of radiant heat due to a fire near the tank and an explosion occurs, the stored flammable liquid becomes It will be discharged to the vicinity and burned, causing a large secondary disaster. Therefore, it is required to have a structure in which only the roof 4 peels off even if an explosion occurs and the structure is detonated upward.

On the other hand, a large negative pressure is generated on the upper surface of the roof 4 of the tank due to a strong wind or the like flowing above the tank roof, but with the necessary strength so that the roof 4 will not be peeled off by this negative pressure. Installation required.

Conventionally, as a mounting means satisfying such requirements, a top angle 5 welded to the upper end peripheral portion of the side plate 3 as shown in a partially enlarged cross section in FIG. 3 (b).
The edge portion of the peripheral edge portion of the roof 4 is welded and fixed to the horizontal flange portion 5a in the airtight state by fillet welding over the entire circumference,
By making the leg length L of the welded portion 6 smaller than the plate thickness of the roof 4, the welded portion 6 is ruptured first when the tank needs to be detonated, so that the tank is detonated upward. It is designed so that the whole is not destroyed.

[0006]

However, in such a welded structure, the strength of the welded portion 6 is not always minimized, and fracture may occur from other portions.

For this reason, it is desirable to make the leg length L of the welded portion 6 as small as possible so that the roof 4 can be easily peeled off when it is necessary to detonate, but on the other hand, in order to keep the tank airtight. Therefore, there is a contradictory demand that it is desirable to sufficiently secure the leg length L of the welded portion 6.

Therefore, it is conceivable that the strength of the welded portion 6 is calculated in advance and welding is performed with the leg length L of the welded portion 6 according to this, but according to experiments, there is a large difference between the calculated value and the measured value. It does not occur due to the pressure as designed and fracture or the welding work for ensuring the airtightness while shortening the leg length L of the welded portion 6 requires highly skilled technology.
Installation of the roof 4 is not easy.

Further, if the leg length L of the welded portion 6 is shortened,
In the case of normally used mild steel, there is a risk that the vicinity of the welded portion 6 will corrode during the life of the tank and there will be holes to allow rainwater or the like to enter.

Further, in the unlikely event that the tank is detonated, the roof 4 of the tank may peel off and fly, which may cause a disaster.

The present invention drastically improves the above-mentioned problems of the prior art, can control the position where the roof is detonated and the position where the detonated roof flies, and can surely detonate when necessary. It is intended to provide a detonation structure for a tank.

[0012]

In order to solve the problems of the prior art, the tank detonation structure according to claim 1 of the present invention has an annular structure at the upper end peripheral portion of the side plate established on the bottom plate. A flange portion is formed, a stainless steel layer is formed by overlay welding on at least a part of the periphery of the flange portion, and at least the inner peripheral edge of the stainless steel plate for detonation is welded around the roof corresponding to the stainless steel layer, The outer peripheral edge of the stainless thin plate is seal-welded to the stainless layer, and a restraint member for restricting movement of the roof due to detonation is provided on the opposite side of the seal-welded portion across the tank center. Is.

Further, the tank detonation structure according to claim 2 of the present invention is characterized in that, instead of the structure according to claim 1, the restraint member is also used as a pipe penetrating the roof. .

[0014]

According to the tank detonation structure of claim 1, a stainless thin plate is welded to a part of the periphery of the tank roof,
This thin stainless plate is welded to the stainless layer by build-up welding formed on the flange at the upper end of the tank side plate, and the strength of the thin stainless plate is reduced so that it can be peeled off from this part for detonation. Is used to prevent corrosion.

Further, a restraint member such as a wire for connecting the roof and the side plate is attached to the side opposite to the explosive portion of the roof, and even when the roof is blown by the explosive, the restraint member serves as a fulcrum for the roof. I try to regulate the movement of.

Further, according to the tank explosion structure of the second aspect, the restraint member is also used as the pipe penetrating the roof, and the pipe opposite to the explosion part is connected to the roof. , By this, the movement of the roof that flies by the bomb is regulated.

By doing so, the stored liquid is prevented from flowing out due to the destruction of the entire tank or the welded portion of the bottom plate and the side plate, and the occurrence of a secondary disaster is prevented.

[0018]

Embodiments of the present invention will be described in detail below with reference to the drawings. 1 (a) and 1 (b) are an exploded perspective view and a partially enlarged sectional view of a tank detonation structure according to the present invention, and the same parts as those in FIG. 3 are denoted by the same reference numerals.

In this tank detonation structure 10, the position where the roof 4 is detonated and the flying direction of the roof 4 when detonated are controlled.

That is, in the tank detonation structure 10, an inverted L-shaped top angle 5 is annularly fixed to the upper edge portion of the side plate 3 of the tank by welding or the like, and a flange portion 5a protruding outward in the horizontal direction thereof. A part of the circumference of the upper surface of the stainless steel layer 1
1 is formed. The thickness of the stainless steel layer 11 formed by the build-up welding is such that there is no hole due to corrosion or the like during the use period (during life) of the tank, and the radial width thereof is also determined in consideration of the corrosion.

On the other hand, the inner peripheral edge of the stainless thin plate 12 is welded and sealed to the roof 4 at a part of the peripheral edge of the roof 4 corresponding to the stainless steel layer 11 welded to the upper surface of the flange portion 5a by welding. The outer peripheral edge of the stainless thin plate 12 and the outer peripheral edge of the other roof 4 are attached in a state of being circular. This thin stainless plate 1
The thickness of 2 is 1/3 of the thickness of the roof 4, which is usually made of mild steel.
It is about 1/4.

Then, the outer peripheral edge of the stainless thin plate 12 is attached in a sealed state by fillet welding on the stainless steel layer 11 which is welded to a part of the circumference of the upper surface of the top angle 5 at the upper peripheral edge of the tank side plate. is there. Further, the outer peripheral edge of the roof 4 other than the outer peripheral edge of the stainless thin plate 12 is directly fillet-welded to the upper surface of the flange portion 5a of the top angle 5 and attached in a sealed state.

The tank detonation structure 10 thus constructed
Then, the leg length of the welded portion of the stainless steel thin plate 12 and the stainless steel layer 11 which is a part of the circumference of the roof 4 is short, and the strength is smaller than that of the welded portion of the other roof 4, so that it is necessary to detonate. By the way, the roof 4 can be peeled off from this portion to cause the detonation, and the position of the detonation can be regulated.

In the case of fillet welding of the stainless steel layer 11 and the stainless steel thin plate 12, the leg length of the welded portion is short and there is a problem of corrosion during use of the tank. Here, the flange portion 5a of the top angle 5 of mild steel is Since the stainless steel layer 11 is formed on the upper surface by overlay welding, corrosion of the top angle 5 can be suppressed by this, and there is no possibility that a hole will be formed in the fillet weld portion with the stainless thin plate 12 due to corrosion. .

On the other hand, a part of the roof 4 is made up of the stainless thin plate 1
By performing fillet welding with the stainless steel layer 11 as 2, it is possible to control the position where the detonation starts so as to start from this portion, but depending on the degree of the force applied by the detonation,
The roof 4 may fly off greatly.

Therefore, in this tank detonation structure 10,
A restraint member 13 that restricts the movement of the roof 4 is provided on the roof 4.

The restraint member 13 for the roof 4 is shown in FIG.
As shown in FIG. 3, brackets 13a are provided on the roof 4 and the outer side surface of the side plate 3 on the side opposite to the circumferential center of the welded portion of the stainless steel layer 11 and the stainless steel thin plate 12 for starting the detonation of the roof 4 of the tank. It is attached by welding or the like, and a wire 13b is attached between two brackets 13a.

Note that a metal rod, a pipe, a chain, or the like can be used instead of the wire 13b connecting the two brackets 13a. Furthermore, the number of the restraint members 13 is not limited to one provided between the roof 4 and the side plate 3, and a plurality of restraint members 13 may be provided adjacent to each other in consideration of the size and weight of the roof 4.

Since such a restraint member 13 is provided, even if the roof 4 is to be detonated, the roof 4 will fly with the restraint member 13 connected to the restraint member 13.
The roof 4 can be dropped in a manner of rotating with the fulcrum as a fulcrum, and the roof 4 can be positioned at a position predicted in advance.

Therefore, the place where the explosion of the roof 4 starts can be regulated by the welded portion of the stainless steel layer 11 and the stainless steel plate 12, and the restraining member 13 can also regulate the position where the roof 4 is blown and dropped. Therefore, by setting the attachment positions of the welded portion and the restraint member 13 in accordance with the surrounding environment, it is possible to surely cause the detonation and to safely detonate.

Next, another embodiment of the present invention will be described.
This will be described with reference to FIG. In this tank detonation structure 20,
The restraint member 21 that regulates the flying direction and the position of the roof 4 at the time of detonation is also used as the tank pipe 22.

In this restraint member 21, a bracket 21a is arranged in the periphery of the pipe 22 penetrating the roof 4 on the side opposite to the welded portion of the stainless steel thin plate 12 and the steres layer 11 which is the starting point of the explosion of the roof 4. The side surface of the pipe 22 and the upper surface of the roof 4 are fixed by welding.

Therefore, by this restraint member 21,
In the unlikely event that the roof 4 is detonated, the roof 4 restrains the members 2
The roof 4 can be detonated in a deformed form with 1 as a fulcrum, and the roof 4 can be prevented from flying greatly.
The roof 4 can be located in the vicinity of the tank side plate 3 predicted in advance.

By using the pipe 22 penetrating the roof 4 of such a tank also as the restraint member 21, the detonation structure can be easily installed.

[0035]

As described above in detail with the embodiments, according to the tank detonation structure of the first aspect of the present invention, a stainless thin plate is welded to a part of the periphery of the tank roof, and the stainless steel plate is welded. Since the thin plate is welded to the stainless steel layer by build-up welding formed on the flange at the upper end of the tank side plate, the strength of the stainless thin plate part can be reduced and it can be peeled off from this part and detonated. It can be used to prevent corrosion.

Further, since a restraint member such as a wire connecting the roof and the side plate is attached to the side opposite to the explosive portion of the roof, even when the roof is blown by the explosives, the restraint member serves as a fulcrum for the roof. Can regulate the movement of.

Further, since the welded portion for defining the explosion location is the welded portion between the stainless layer and the stainless thin plate,
During the life of the tank, there is no hole due to corrosion, and it is possible to prevent the ingress of rainwater and the like.

According to the tank detonation structure of the second aspect, the restraint member is also used as a pipe penetrating the roof, and the pipe on the side opposite to the detonation portion is connected to the roof. By doing so, the movement of the roof that is blown by the bomb can be restricted, the roof can be safely blown, and the structure is simple.

Further, according to these inventions, the explosion position of the tank roof and the movement of the exploded roof can be regulated. By doing so, the stored liquid flows out due to the destruction of the entire tank or the welded portion of the bottom plate and the side plate. This prevents the occurrence of secondary disasters.

[Brief description of drawings]

FIG. 1 is an exploded perspective view and a partially enlarged sectional view of an embodiment of a tank detonation structure according to the present invention.

FIG. 2 is a perspective view and a partially enlarged sectional view according to another embodiment of the tank detonation structure of the present invention.

FIG. 3 is a perspective view and a partially enlarged sectional view of a conventional tank detonation structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Foundation 2 Bottom plate 3 Side plate 4 Roof 5 Top angle 5a Top angle flange 6 Welded portion 10 Tank detonation structure 11 Stainless steel layer (buildup welding) 12 Stainless steel thin plate 13 Restraint member 13a Bracket 13b Wire 20 Tank detonation structure 21 Restraint member 21a Bracket 22 Piping

Claims (2)

[Claims] 1. A side plate formed on a bottom plate is formed with an annular flange portion at an upper peripheral edge portion thereof, and a stainless steel layer is formed by overlay welding on at least a part of the periphery of the flange portion, and at least the stainless steel layer is provided. While welding the inner peripheral edge of the stainless thin plate for detonation around the roof, the outer peripheral edge of this stainless thin plate is seal-welded on the stainless steel layer, and the roof is on the opposite side of the seal welded part across the tank center. An explosive structure for a tank, which is provided with a restraining member for restricting movement due to the explosive explosion of the tank. 2. The tank detonation structure according to claim 1, wherein the restraint member is also used as a pipe penetrating the roof plate.