JPS6332946B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a double-shelled cylindrical cryogenic tank for storing liquefied petroleum gas, liquefied natural gas, etc.

Conventionally, in one example of a construction method for this type of cylindrical cryogenic tank, an inner tank roof is assembled, an outer tank roof is assembled on the outside of the inner tank roof, and a plurality of lifting devices are installed around the outer periphery of the inner tank roof. While hoisting the tank roof, assemble the outer tank side plates from the top to the bottom in order from the bottom of the outer circumferential side plate of the outer tank roof. After completing the assembly of the outer tank at a predetermined height, move the lifting device onto the outer tank roof. While the inner tank roof is lifted by this lifting device, the inner tank side plates are successively added under the inner tank roof to complete the inner tank. However, in this case, the bottom cold insulation and inner tank bottom plate must be constructed first or after the above work is completed, so other work cannot be carried out in parallel during the construction period.
The construction period was longer, and after assembling the inner tank roof, the outer tank roof was assembled on the outside.This was lifted using a lifting device around the outer periphery of the inner tank roof while the outer tank side panels were assembled. Furthermore, there are drawbacks such as lack of stability in supporting the outer tank side plates, and furthermore, the lifting device must be moved to the outer tank roof after the outer tank is completed, which is time consuming and difficult.

Therefore, an object of the present invention is to assemble the outer tank side plate and assemble the lower part of the inner tank side plate to the upright part of the inner tank side plate, and to remove the inner tank from the lower part of the inner tank side plate. Assemble the knuckle plate. Assemble the inner tank roof to this inner tank knuckle plate. Separately from the inner tank roof, assemble the outer tank roof using the outer tank side plate as a support and the inner tank roof as a scaffold. After completing the assembly of the outer tank side panels, compressed air is sent to the lower part of the outer tank roof to float the outer tank roof and fix it to the upper end of the outer tank side panels, and multiple upper racks are installed on the fixed outer tank roof. The inner tank roof is raised to a predetermined height using a device, and the remaining inner tank side panels carried into the outer tank are assembled from the upper level.This process of raising the inner tank roof and assembling the inner tank side panels is repeated alternately to complete the inner tank. A cylindrical low-temperature tank with a cylindrical low-temperature tank that was designed to shorten the construction period by completing the assembly of the tank and simultaneously installing the bottom insulation material and the bottom plate of the inner tank, making it possible to assemble the side plates of the inner tank on low-level scaffolding. The purpose is to provide a construction method.

Other objects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings.

The drawings show step by step some of the steps in an embodiment of the method for constructing a cylindrical cryogenic tank according to the present invention.

First, as shown in Fig. 1, the outer tank bottom plate 1 is placed on the foundation and the lowest stage of the outer tank side plates 2 is assembled, and then the outer tank side plates 2 are assembled successively from the lower stage to the upper stage. go. In addition, a pearlite concrete ring 3 is placed in the upright portion of the inner tank side plate on the outer tank bottom plate 1.

When the curing of the pearlite concrete ring 3 is completed, the inner tank annular plate 3' is provided on the pearlite concrete ring 3, and the lower part of the inner tank side plate 4 is assembled thereon as shown in FIG.

Next, as shown in FIG. 3, the inner tank knuckle plate 5 is assembled using the previously assembled lower part of the inner tank side plate 4 as a stand. At the same time, the assembly of the outer tank side plates 2 is successively performed.

After the inner knuckle plate 5 is assembled as shown in FIG. 3, the inner tank roof 6 is first assembled to the inner tank knuckle plate 5, and
Separately from this inner tank roof 6, as shown in FIG. 4, an outer tank roof 7 is assembled using the outer tank side plates 2 as supports and the inner tank roof 6 as a scaffold. Further, the inner tank roof 6 and the outer tank roof 7 are separated and do not form a composite roof.

In this way, when the assembly of the outer tank side plate 2 is first completed, the construction opening of the outer tank side plate 2 is temporarily closed airtight, and compressed air is sent into the lower part of the outer tank roof 7, that is, inside the outer tank 10, and the air pressure is increased. Therefore, the outer tank roof 7 is lifted up and fixed to the upper end of the outer tank side plate 2. Once the outer tank roof 7 is fixed to the upper end of the outer tank side plate 2 as shown in FIG.
The inner tank roof 6 is raised to a predetermined height by means of these lifting devices 8, as shown in FIG. The raised height of the inner tank roof 6 at this time is suitably determined to be sufficient to perform the next assembly work of the inner tank side plate 4 on a scaffold installed at a low fixed position. Also, at this point, construction of the bottom heat insulating material 16 and the inner tank bottom plate 18 is started.

After the outer tank roof 7 is fixed in this way and the inner tank roof 6 is raised to a predetermined height by the lifting device 8, the inner tank roof 7 is installed inside the outer tank roof 7 as shown in FIG. The remaining inner tank side plate 4 is assembled by taking in the remaining inner tank side plate 4 from the construction opening 12 of the outer tank 10 using a trolley hoist 9 disposed so as to be movable along the guide rail. In this case, the inner tank side plates 4 are assembled from the upper tier, and after the inner tank side plates are assembled for each tier, they are lifted up by the lifting device 8, so the assembly position of the inner tank side plates of each tier remains constant. Assembly work will proceed on the scaffolding at the location. In this way, the assembly work of the inner tank side plate 4 is progressed step by step from the upper stage of the inner tank side plate to the lower stage, and finally the inner tank side plate 4 of the lowest stage assembled on the inner tank annular plate 3' at the beginning. The entire assembly work of the inner tank side plate 4 is completed when welding of the circumferential joint with the next stage is completed. Also,
In parallel with this inner tank side plate assembly work, the bottom insulation material 16
The construction work of the inner tank bottom plate 18 is continued, and various works are carried out simultaneously, so the construction period is shortened and time and costs can be saved.

As described above, according to the method for constructing a cylindrical low-temperature tank of the present invention, while assembling the outer tank side plate, the inner tank side plate is attached to the upright portion of the inner tank side plate via the perlite concrete ring and the inner tank annular plate. Assemble the lowermost inner tank side plate, assemble the inner tank knuckle plate on the bottom of this inner tank side plate, and further assemble the inner tank roof. Separately from this inner tank roof, use the outer tank side plate as a support and Assemble the outer tank roof using the tank roof as a scaffold. After completing the assembly of the outer tank side panels, compressed air is sent to the lower part of the outer tank roof to float the outer tank roof and fix it to the top of the outer tank side panels. A lifting device is installed on the fixed outer tank roof, and this raises the inner tank roof to a predetermined height, corresponding to the low position where the inner tank plates brought in from the outer tank construction opening can be assembled. In order to erect the inner tank side plates sequentially from the upper to the lower tier, the process of raising the inner tank roof and assembling the inner tank side plates was repeated alternately to complete the assembly of the inner tank, and at the same time, the bottom insulation material and the inner tank bottom plate were installed. Since the construction work can be done in advance, the construction period can be shortened, and the construction work for the inner tank side panels and bottom panels can be done inside the outer tank, so it is not affected by weather conditions, and after the outer tank is completed, the inner tank side panels and other tanks Since the materials are taken in through the construction opening, there is no need for a running area for heavy machinery as in the past, and it is also possible to work on low scaffolding, such as when assembling the inner tank side panels, greatly improving work at heights. It is possible to reduce the amount of heat generated, and there are advantages such as better consideration in terms of safety.

[Brief explanation of the drawing]

FIGS. 1 to 7 are vertical cross-sectional schematic explanatory views showing step by step various steps of the method for constructing a cylindrical cryogenic tank according to the present invention. In the figure, 1... Outer tank bottom plate, 2...
...Outer tank side plate, 3...Pearlite concrete ring, 3'...Inner tank annual plate, 4...Inner tank side plate, 5...Inner tank nutcle plate, 6...Inner tank roof, 7...Outer tank Roof, 8... Elevation device, 9...
... Trolley hoist, 10 ... Outer tank, 12 ... Construction opening, 16 ... Insulation material, 18 ... Inner tank bottom plate.

Claims (1)

[Claims] 1 Assemble the outer tank side plate of a cylindrical low-temperature tank with a double shell structure, assemble the lower part of the inner tank side plate on the upright part of the inner tank side plate, and assemble the inner tank knuckle plate on the lower part of the inner tank side plate. Assemble the inner tank roof to the tank nutcle plate, and then assemble the outer tank roof separately from the inner tank roof. After completing the assembly of the outer tank side plates, compressed air is sent to the lower part of the outer tank roof to install the outer tank roof. The remaining inner tank roof is floated up and fixed to the upper end of the outer tank side plate, and then the inner tank roof is raised to a predetermined height using multiple lifting devices installed on the fixed outer tank roof. A method of constructing a cylindrical low temperature tank in which the tank side plates are assembled from the upper level, and the inner tank is assembled by repeating alternately raising the inner tank roof and assembling the inner tank side plates.