JPH0321432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to, for example, a method for assembling a tank corner portion of a base tank for petroleum storage.

Prior Art First, an outline of an underground oil storage tank will be explained based on FIG. 1 is a tank body consisting of a concrete wall and a lining arranged on its inner surface;
2 is a floating roof body that can be freely raised and lowered within the tank body 1;
A seal 3 is disposed on the outer circumferential surface of the floating roof body 2 and abuts on the inner circumferential surface of the tank body 1, and a seal 4 is erected on the bottom surface of the tank body 1 and whose upper end penetrates the floating roof body 2. It is a pipe shaft, and a drainage pump piping 5 is arranged inside. 6 is a pump interposed in the pipe 5; 7 is a rainwater outlet provided at the center of the lower surface of the floating roof main body 2; 8 is a folding type drain connecting the rainwater outlet 7 and the lower end opening of the drainage pump pipe 5. It's plumbing.

In the above configuration, the lining of the tank body 1 has conventionally been performed as follows. That is, as shown in FIGS. 4 and 5, an annular plate 10 is welded to the outer peripheral edge of the tank bottom plate 9, and a tank side plate 11 is placed on the annular plate 10 with a slight drainage gap α. The lower end of this tank side plate 11 is welded 12 to the annular plate 10. The construction is such that rainwater that falls during the on-site construction is discharged to the outside of the tank body 1 through the gap α.

Problems to be Solved by the Invention However, in this conventional method, rust 13 may occur in the groove on the lower end surface of the tank side plate 11, and foreign matter 14 may accumulate in the gap α, which may cause defects during welding. It's summery.

The present invention solves the above problems and can reliably drain rainwater during construction, and prevents rust from forming on the lower end of the tank side plate and the outer periphery of the tank bottom plate, which are the welding points, and prevents foreign matter from accumulating at the welding points. It is an object of the present invention to provide a method for assembling a tank corner part that enables complete and accurate welding without any problems.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides that the lower end of a construction ring having a drain port at a proper position at the lower end is attached to the inner periphery of the upper surface of the annular plate, which is welded to the upper surface of the ring, and the lower surface of the tank bottom plate. welding the outer peripheral edge, and welding the lower end outer peripheral surface of the tank side plate to the upper inner peripheral surface of the construction ring;
A method of disposing a knuckle plate between the tank side plate and the tank bottom plate and welding the knuckle plate to the tank side plate and the tank bottom plate after draining rainwater that fell into the tank during on-site construction from the drain port. This is what I did.

Effect: With the above method, rainwater that fell during on-site construction prior to welding the Knuckle Plate can be drained out of the tank from the drain hole formed in the construction ring, and the Knuckle Plate is finally placed between the tank side plate and the tank bottom plate. Once placed, one end of the knuckle plate and the lower end of the tank side plate are welded, and the other end of the knuckle plate and the outer circumference of the tank bottom plate are welded, but the lower end of the tank side plate at this welding point The outer periphery of the tank bottom plate is resistant to rust and foreign matter buildup, making it possible to perform complete and accurate welding.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

16 is an annular plate (annular plate) that also serves as a backing metal, and on its upper surface, there is a drainage hole 18 at the appropriate place at the bottom end.
The construction ring 19 formed with is welded 20. These annular plates 16 and construction rings 19 are manufactured in advance at a factory and then transported to the site for use. This Anyura plate 1
The outer circumferential edge of the lower surface of the tank bottom plate 9 is welded 17 to the inner circumferential edge of the upper surface of tank bottom plate 6, and the outer circumferential surface of the lower end of tank side plate 11 is welded to the inner circumferential surface of the upper end of the construction ring 19.

22 is the lower end surface of the tank side plate 11 and the tank bottom plate 9
A knuckle plate placed between the outer peripheral surfaces of
The cross section is formed into a circular arc shape, and the knuckle plate 22
One end surface is welded 23 to the lower end surface of the tank side plate 11, and the other end surface is welded to the outer peripheral surface of the tank bottom plate 9 to form a corner portion of the tank bottom.

Next, the assembly sequence of the corner portion of the tank bottom will be explained.

First, the construction ring 19 is welded to the upper surface of the annual plate 16 in advance at the factory, on the inner periphery of the upper surface.
The outer peripheral edge of the lower surface of the tank bottom plate 9 is welded 17. Next, the lower end outer circumferential surface of the tank side plate 11 is welded 21 to the upper inner circumferential surface of the construction ring 19. Rainwater that falls inside the tank during the on-site construction is discharged to the outside of the tank from a drain port 18 formed in the construction ring 19. Finally, the knuckle plate 22 is fitted between the lower end surface of the tank side plate 11 and the outer peripheral surface of the tank bottom plate 9, one end surface of the knuckle plate 22 and the lower end surface of the tank side plate 11 are welded, and the nut The other end surface of the tank plate 22 and the lower end surface of the tank bottom plate 9 are welded to assemble the tank corner portion.

Effects of the Invention As described above, according to the present invention, before the knuckle plate is welded, the rainwater that falls inside the tank is disposed outside the tank through the outlet of the construction ring, so the tank side plate The lower end of the tank and the outer periphery of the tank bottom plate are resistant to rust, and even if rust does occur, the rust can be easily scraped off. Further, foreign matter does not accumulate at the welding location. Therefore, it is possible to completely and accurately weld the nut plate to the tank side plate and tank bottom plate.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the present invention, with Figure 1 being a vertical sectional view of a corner portion, Figure 2 being a partially cutaway perspective view of an annular plate and a construction ring, and Figure 3 being a partially cutaway perspective view of an annular plate and a construction ring. 1 is a schematic vertical cross-sectional view of an underground oil storage tank, and FIGS. 4 and 5 are a perspective view and a vertical cross-sectional view showing a conventional example. DESCRIPTION OF SYMBOLS 1... Tank body, 2... Floating roof main body, 9... Tank bottom plate, 11... Tank side plate, 16... Annular plate, 17, 20, 21, 23... Welding, 18... Drain port, 19... Construction ring, 22... Natsukuru plate.

Claims (1)

[Claims] 1. Weld the outer circumferential edge of the lower surface of the tank bottom plate to the inner circumferential edge of the upper surface of the annular plate, the lower end of which has a drainage port at the appropriate location on the lower end of the annular plate, and attach the inner circumferential surface of the upper end of the construction ring to the inner circumferential surface of the tank side plate. After welding the outer peripheral surface of the lower end and discharging rainwater that fell into the tank during on-site construction from the drain port, a knuckle plate is placed between the tank side plate and the tank bottom plate, and the knuckle plate is attached to the tank side plate and the tank bottom plate. A method for assembling a tank corner portion, which is characterized by welding to the tank bottom plate.