JPS6238237B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for watering a floating roof tank.

For example, in a group of underground oil storage tanks, if one of the tanks catches fire, the radiant heat will heat the upper ends of the outer peripheral walls of the adjacent tanks, causing the outer peripheral surface of the floating roof body installed inside the tank body to heat up. The seal that is provided and contacts the inner circumferential surface of the tank body may be thermally damaged, and there is a risk that the oil stored in the tank may burst into flames.

Conventionally, a sprinkler system has been installed on the top surface of the floating roof body, but this system is of no use in case the piping is damaged during an earthquake and a fire is expected to occur following the earthquake. Conventionally, it has been considered to spray water directly onto the top surface of the floating roof body from outside the tank, but in this case, there is a large difference between when the floating roof body rises and when it descends, so water is sprayed directly onto the top surface of the floating roof body. It is difficult to water evenly.

The present invention has been made in view of the above problems, and its feature is that cooling water is injected from outside the tank to the upper part of the inner circumferential surface of the tank body to prevent the upper surface of the floating roof body of the reverse slope type. Water is sprinkled on the outer periphery, and cooling water is injected from outside the tank to the center of the upper surface of the floating roof body, and the cooling water is sprayed into multiple circles concentric with the center of the floating roof body at the center of the upper surface of the floating roof body. Water is dispersed by weirs arranged at appropriate intervals above the roof and sprinkled on the center of the upper surface of the floating roof. According to this method, there is no sprinkler system installed on the floating roof, so there is no risk of earthquake damage. This solves the problem of not being able to spray water due to damage to pipes. Also, instead of spraying water directly onto the top surface of the floating roof body, cooling water is sprayed onto the top of the inner peripheral surface of the tank body and the center of the top surface of the floating roof body, and then water is sprinkled onto the top surface of the floating roof body. Even if the floating roof body is rising or falling, water can be evenly sprinkled over the entire upper surface of the floating roof body without being affected by it.

Hereinafter, one embodiment of the present invention will be described based on the drawings. This example relates to an underground tank for petroleum storage,
Reference numeral 1 denotes a reverse slope type floating roof body disposed in a tank body 2 so as to be able to rise and fall freely, and the upper surface outer circumferential portion 1A and the upper surface center portion 1B, which are located between the annular groove 3 formed on the upper surface, are annular. It slopes downward toward the groove 3. Reference numeral 4 denotes weir plates arranged at appropriate intervals on three concentric circles with respect to the center O of the floating roof main body 1 in the center part 1B of the upper surface, and cutouts 5 are provided at appropriate intervals on the lower edge. It has been formed. 6
is a drainage shaft that is erected on the bottom surface of the tank body 2 and passes through the floating roof body 1, and a drainage pump 7 is disposed inside. 8 is a pump pipe whose lower end is connected to the discharge port of the drain pump 7 and whose upper end extends outside the tank through the upper surface of the drain shaft 6; 9 is a pump pipe connected to the drain port 10 of the annular groove 3 and the lower end of the drain shaft 6; A foldable drain pipe that communicates with the water intake port 11, 12 is the floating roof main body 1
The seals 13 are arranged on the outer peripheral surface of the tank body 2 and are in contact with the inner peripheral surface of the tank body 2, and 13 is a plurality of straight seals (eight in this embodiment) arranged at appropriate intervals in the circumferential direction above the tank body 1. It is a nozzle and faces the center O of the floating roof body 1. 14 is a water supply pipe connecting the straight nozzles 13 to each other, 15
are a large number of branch pipes arranged at appropriate intervals in the circumferential direction so as to straddle the tank body 2, and the spray nozzle 16 provided at the tip of each branch pipe 15 is located at the upper part of the inner peripheral surface of the tank body 2. It's suitable. 17 is a water supply pipe that connects the branch pipes 15 to each other.

In the above configuration, when water is supplied to each water supply pipe 14, 17, cooling water is first injected from each straight nozzle 13 toward the center O of the floating roof body 1,
The cooling water falls to the center of the upper surface of the floating roof main body 1, flows over the upper center portion 1B, and tries to flow into the annular groove 3, but the flow is obstructed by the weir plate 4.
It is diffused through both sides of the weir plate 4 and through the notch 5. Therefore, the center portion 1B of the upper surface is evenly covered with cooling water. Further, cooling water is injected from each spray nozzle 16 toward the upper part of the inner peripheral surface of the tank body 2 via each branch pipe 15, and the cooling water travels along the inner peripheral surface of the tank body 2 to the seal 12.
It falls upward, flows evenly covering the upper surface outer peripheral portion 1A, and flows into the annular groove 3. The water in the annular groove 3 is sucked into the drainage shaft 6 through the drain pipe 9, and is discharged to the outside of the tank through the pump piping 8 by the drainage pump 7. Furthermore, the water sprinkling condition does not change at all whether it is in the solid line state in FIG. 1 or in the imaginary line state in the figure, and is not affected by the elevation of the floating roof body 1.

As described above, according to the water sprinkling method for a floating roof tank of the present invention, since no water sprinkling device is provided on the floating roof body, piping is damaged by an earthquake.
This solves the problem of not being able to sprinkle water.
Also, instead of spraying water directly onto the top surface of the floating roof body, cooling water is sprayed onto the upper inner peripheral surface of the tank body and the center of the top surface of the floating roof body, and then water is sprinkled onto the top surface of the floating roof body. To evenly sprinkle water over the entire upper surface of a floating roof body without being affected by the rising or falling of the floating roof body.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which FIG. 1 is a schematic vertical sectional view, FIG. 2 is a schematic plan view, and FIG. 3 is a perspective view of a weir plate. 1...Floating roof main body, 1A...Top outer periphery, 1B
...Top center, 2... Tank body, 4... Weir plate, 5... Notch, 13... Strain nozzle, 1
6...Spray nozzle.

Claims (1)

[Claims] 1 Cooling water is injected from outside the tank to the upper part of the inner peripheral surface of the tank body, and water is sprinkled on the upper surface outer periphery of the floating roof body of the reverse slope type, and cooling water is injected from outside the tank to the center of the upper surface of the floating roof body. At the same time, the cooling water is diffused into the center of the upper surface of the floating roof body by weirs arranged at appropriate intervals on a plurality of circles concentric with the center of the floating roof body. A watering method for a floating roof tank characterized by sprinkling water.