JPS6151110B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for assembling the roof of a cylindrical storage tank.

Conventionally, in the method of assembling the roof of a cylindrical storage tank, for example, as shown in FIGS.
First, the center column 5, intermediate column 6, and end column 7 are assembled on top, and the inner and outer tank roofs 4, 4' as shown are assembled on these columns 5, 6, 7. Next, a side support 9 is provided on the inner tank side plate 3, and the inner and outer tank roofs 4, 4' are supported by temporary rafters 8, and the inner and outer tank roofs 4, 4' are first supported.
4′, the center support 5, intermediate support 6,
The end supports 7 are removed, and the bottom plates 11 are arranged and welded (FIG. 2). After welding the bottom plate 11, a cold insulation material is laid on the bottom outer tank bottom plate 1 to form the bottom cold insulation structure 12, and a parallel holding frame is attached to the knuckle plate 14 attached to the top of the inner tank side plate 3. 15 and setting the leveling wires 16, preparations for floating the inner and outer tank roofs 4, 4' can be made (FIG. 3). Temporary rafters 8 are installed to float the inner and outer tank roofs 4 and 4' using compressed air.
A temporary roof is provided on the inner tank side plate 3, and a seal plate 17 (Fig. 4) is provided on the periphery of the temporary rafter 8.
The compressed air is airtight between the inner and outer tank roofs 4,
4', the inner and outer tank roofs 4, 4' are raised by the leveling wire 16 while maintaining the levelness and stability of the inner and outer tank roofs 4, 4'. Also, the roof 4,4' up to the final installation height.
As shown in FIG. 4, a temporary side plate 18 may be provided above the inner tank side plate 3 as an airtight measure in order to float the inner tank side plate 3.

In this conventional method of assembling the roof of a cylindrical storage tank, there are problems with quality control because the side supports are welded to the inner tank side plate, and inspection work of the welded part of the side supports and disassembly work of the side supports are required. 2. When moving from roof assembly work to bottom plate and bottom cooling-related work, the pedestals must be moved from the center, intermediate and end supports to the side pedestals, 3. Before the roof is raised, the pedestals must be moved to the side pedestals. The restraint between the platform and the roof frame is released, but if an eccentric load is applied to the roof at this time, the balance is likely to be lost and it is very dangerous.4. There are many problems, such as the need to use special equipment.

Furthermore, as shown in Fig. 4, in an open-top inner tank, the roof can only be floated up to the upper end of the inner tank side plate 3, and in order to float the roof to a predetermined position, it is necessary to It was necessary to specially provide a temporary side plate 18 above for airtight sealing.

Therefore, an object of the present invention is to solve such problems in the conventional art by erecting end supports on an annular plate and providing a temporary rafter thereon to form a roof frame pedestal, Assemble the roof on top of the center support provided at To provide a method for assembling a roof of a cylindrical storage tank, characterized in that the roof is floated together with a pedestal by feeding compressed air into the tank, and the pedestal is separated and lowered after the roof is attached.

According to this invention, the roof of the cylindrical storage tank is constructed by erecting end supports on the annular plate and providing temporary rafters to form the roof frame pedestal, and on top of the center support provided at the center of the bottom plate. After assembling the roof, remove the center support, set the leveling wire using the mounting piece provided on the knuckle plate attached to the top of the side plate, and float the roof together with the pedestal using compressed air. After the roof is attached, the pedestal is separated and lowered using a winch, chill hole, etc., thereby saving labor and increasing safety in roof assembly work and roof floating work.

Other objects, features and advantages of the invention will become apparent from the detailed description below.

5 to 7 sequentially show the process of assembling the roof of a cylindrical storage tank with a double shell structure manufactured by the cylindrical storage tank roof assembly method of the present invention.
As shown in the figure, first, the end support 21 is erected on the annular plate 10 placed on the ring concrete 2, apart from the inner tank side plate 3, and fixed by the support support 22. At the upper end of this end support 21, a second
A roof frame pedestal 20 composed of a ring 26, a temporary rafter 24, and a first ring 25 is provided. The inner and outer tank roofs 4, 4' are assembled on this roof frame pedestal 20 and a center column 5 provided at the center of the outer tank bottom plate 1. When assembling the inner and outer tank roofs 4, 4', intermediate supports may optionally be used if necessary. Once the inner and outer tank roofs 4, 4' are assembled in this manner, a temporary roof is provided on the temporary rafter 24, and a seal plate 28 is provided on the peripheral edge to ensure airtightness between the inner tank side plate 3 and the inner tank side plate 3. Next, the center support 5 is removed, a temporary pedestal 19 is installed, and the bottom plates 11 of the inner tank are arranged and welded (Fig. 6).
9 is removed to form the bottom cold insulation structure 12, and the bottom plate 1 is removed.
1 onto the bottom cold storage structure 12.

In this way, the assembly work of the inner and outer tank roofs 4, 4' is completed, and the bottom plate 11 and the bottom cold insulation structure 12 are completed.
Once the inner and outer tank roofs 4,
4' is ready to float. As shown in FIG. 7, when preparations for floating the inner and outer tank roofs 4 and 4' are completed, compressed air is sent under the inner and outer tank roofs 4 and 4' to move the inner and outer tank roofs 4 and 4' together with the roof frame pedestal 20. The tank roofs 4, 4' are floated up to a predetermined height while being balanced by a leveling wire 32.
The inner and outer tank roofs 4, 4' which have been floated to a predetermined height are welded and connected to the knuckle plate 14 attached to the top of the inner tank side plate 3, thereby completing the roof. Once the inner and outer tank roofs 4, 4' are installed in this way,
The roof frame pedestal 20, which was floated together earlier, is separated from the roof and suspended using a winch, chill hole, or the like.

In addition, the roof frame pedestal that is separated from the roof can be separated from the entire circumference as an annular integral piece and then used as a winch.
They may be disassembled individually on the ground after being suspended in a chill hole, or they may be separated from the roof as members of appropriate size and dismantled, and then used with a winch,
It may also be suspended through a chill hole or the like.

Furthermore, it is also possible to increase the roof floating height by installing a plate, sheet, etc. between the end supports 21 and providing a seal plate 28 at the lower end to ensure airtightness with the inner tank side plate 3. (Figure 8).

As described above, according to the cylindrical storage tank roof assembly method of the present invention, in parallel with the assembly work of the outer tank and inner tank side plates, the roof of the cylindrical storage tank is installed at a distance from the inner tank side plates so as not to damage the inner tank side plates. A roof frame pedestal consisting of the first and second rings and a temporary rafter supported by the end supports is provided, and the roof can be assembled on the roof frame pedestal using the center column, and the roof frame is The pedestal has a double ring structure, so it is very strong and has enough strength to support the weight of the roof, making it safe. After the roof is assembled, the center column can be removed and the roof frame pedestal can be replaced. Since the bottom plate and bottom cold insulation work can be started without any work, labor is significantly reduced and the construction period can be shortened. Once the roof is completed and the bottom plate and bottom cold insulation structure are completed, the leveling wire can be set very easily by providing a mounting piece inside the knuckle plate at the top of the inner tank side plate, and then the compressed air can be installed on the roof. If the roof is floated together with the roof frame holder by sending it under the roof, the amount of work during levitation can be reduced, and the center of gravity will be lowered by the amount that the roof frame holder is attached to the lower part of the roof. This improves stability when the roof floats up, making it safer.Also, even in open-top inner tanks, the cradle has sufficient length in the vertical direction, so there is no need to specially install temporary side plates. The roof can be floated up to a predetermined height while maintaining airtightness, and the final installation of the roof to the nutkl plate is simple and easy.After the roof installation is complete, the roof frame pedestal can be separated from the roof and used with a winch or chill hole. It is sufficient to simply suspend the workpiece by means of a method such as the above, and it is possible to achieve effects such as shortening the construction period, reducing the amount of work, saving labor, and increasing safety. Note that the present invention is not limited to double-shelled tanks, but can also be used for single-shelled tanks and underground tanks.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional schematic diagrams showing a step-by-step method of assembling the roof of a conventional cylindrical storage tank; Figure 4 is a cross-sectional schematic diagram showing how to assemble the roof of an open-top tank; Figures to Figures 7 are cross-sectional schematic diagrams showing step-by-step the cylindrical storage tank roof assembly method of the present invention;
FIG. 8 is a schematic cross-sectional view showing an example in which the assembly method of the present invention is applied to assembling the roof of an open-top inner tank. In the diagram, 1...outer tank bottom plate, 2...ring concrete, 3...
Inner tank side plate, 4, 4'... Inner and outer tank roof, 5... Center support, 6... Intermediate support, 7... End support, 8... Temporary rafter, 9... Side support, 11... Bottom plate, 12... Bottom cold insulation structure, 14... Knuckle plate, 15... Parallel holding frame, 16... Leveling wire, 17... Seal plate, 20... Roof frame cradle, 21... End support, 22... Strut holder, 24... Temporary rafter, 25... First ring , 26...Second ring, 28...Seal plate, 31...Mounting piece, 32...Leveling wire.

Claims (1)

[Claims] 1 A temporary rafter that slopes upward in the radial direction is provided on the end support that is erected on the annular plate on the inner side away from the inner tank side plate to form an annular roof pedestal,
Assemble the roof while supporting it with the pedestal and the center column provided at the center of the bottom plate, remove the center column after the roof is assembled, and attach the leveling wire using the mounting piece provided on the knuckle plate attached to the top of the side plate. A method for assembling a cylindrical storage tank roof.