JPH0285468A - Scaffolding for installing structure in container - Google Patents

Abstract

PURPOSE:To simplify the carry-in and carry-out works and simplify the assembly work by mutually connecting and inserting the cylindrical first - fourth members having flanges at the edge parts. CONSTITUTION:Each of the lower pipe 1 of the first member, intermediate pipe 2 of the second member, upper pipe 3 of the third member, and the receiving cup 4 of the fourth member is formed by connecting and inserting a cylindrical member having a flange at the edge part. Further, a lower flange 2a is installed at the lower edge of the intermediate pipe 2, and an upper flange 2b for supporting the flange 3a of the upper pipe 3 and the flange 4a of the receiving cup 4 is installed at the upper edge. The upper pipe 3 having the flange 3a for fixing a scaffolding plate 6 at the upper edge of the upper pipe 3 by bolts 7 is inserted into the intermediate pipe 2 and the lower pipe 1. Therefore, the period necessary for the installation work for an inside structure body can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a temporary scaffold for the installation of a structure installed in a large vessel such as a nuclear reactor pressure vessel.

(Prior art) There is work to install various reactor internals inside large vessels such as reactor pressure vessels of nuclear power plants, etc. For example, for a cylindrical shroud, the lower and upper shells In order to prevent deformation that occurs when welding with A line connecting the two points and the center of the control rod drive mechanism attachment stub tube provided at the bottom of the reactor pressure vessel is used to check for shroud ``collapse.'' The scaffolding used to weld the shroud is installed at the bottom of the reactor pressure vessel specifically for the shroud. After welding this shroud, the next step is to install the lattice-shaped core support plate, but at this time, the work position is at a different height than when the shroud was installed, so the shroud centering jig, core support plate, Dismantling the shroud-specific scaffolding, etc.
After the reactor pressure vessel was removed, a special scaffold for the core support plate was reassembled inside the reactor pressure vessel.

(Problem to be solved by the invention) When installing a low-position shroud, the core support plate located above it is temporarily installed, and a scaffold dedicated to the shroud is required, and then when the core support plate is installed, it must be installed first. The shroud centering jig, core support plate, and shroud-dedicated scaffold had to be removed, and then the core support plate-dedicated scaffold had to be assembled, and work inside the reactor pressure vessel was congested due to the location and shape of the installed structures. Another disadvantage was that it took a long time.

The present invention has been made in view of the above, and its purpose is to provide a structure in which the height of the work scaffold can be adjusted, and which can be easily dismantled, so that it can be used commonly for work inside the vessel, such as installing shrouds and core support plates. Our purpose is to provide scaffolding for installing container internal structures.

[Structure of the Invention] (Means for Solving the Problems) A cylindrical body having a flange fitted into a hole provided at the bottom of a container, etc. at one end, and a flange connected to a second member at the other end. a second member having a flange connected to the first member at one end and a flange supporting a third member at the other end; a third member that can be inserted into the member and the first member, a flange into which the third member is inserted, one end abutting the flange of the second member, and the other end the third member. The fourth member is provided with a bottom portion that abuts and supports the tip of the member, and is capable of being fitted into the second member.

(Function) The dimensions of a large number of cylindrical scaffolding members are set in advance, the first member and the second member are connected with bolts and nuts, and the third member is inserted into this and temporarily fixed, and the outer shape is determined. Pack them into small pieces and transport them into the assembly container. Fit the first member into the numerous holes provided at the bottom of the container, and secure the scaffolding boards to the flanges at the top of the first member with nuts to complete the scaffolding for the bottom of the container. do. After the work to go down to the lower part of the container is completed, in order to raise and install the scaffolding board for the work on the upper part of the container, the scaffolding board and the third member are moved by a crane, and the third member is moved from the second member. Lift the fourth member until it comes out, fit the fourth member onto the top of the second member, and secure it with a bolt and nut. Then, insert the bottom end of the third member into the fourth member, and tighten it with the fourth member. By supporting it, the upper scaffolding will be completed.

In addition, when dismantling and transporting the scaffold, the scaffolding can be assembled into smaller pieces in the same way as when the original scaffolding members were brought in by reversing the assembly process described above, or each member can be disassembled into individual parts to make them smaller in size and weight, making them easier to handle, and then transporting them out of the container. do.

Note that if the first member and the second member are interconnected horizontally using reinforcing tools, the rigidity of the entire scaffold increases and safety is further improved.

(Example) An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view, and FIG. 2 is a longitudinal sectional view. The present invention consists of a lower pipe 1 which is a first member, an intermediate pipe 2 which is a second member, and an upper part which is a third member. The lower end of the lower pipe 1 is connected to the stub tube 5 of the control rod drive mechanism provided at the bottom of the reactor pressure vessel 9. A lower flange 1a to be fitted is formed at the upper end thereof, and an upper flange 1b to be connected to the lower flange 2a of the intermediate pipe 2. Further, a lower flange 2a is provided at the lower end of the intermediate pipe 2, and a flange 3 of the upper pipe 3 is provided at the upper end.
The upper pipe 3 is provided with an upper flange 2b that supports the flange 4a of the cup 4.The upper pipe 3 has a flange 3a on its upper end that fixes the scaffold board 6 with bolts and nuts 7. When the cup 4 is inserted into the middle pipe 2 and the cup 4 is used, the cup 4 is inserted into the intermediate pipe 2.
The bottom part 3b is fitted onto the inner circumference of the cup 4, and the bottom part 3b is inserted into the bottom part 4b of the cup 4.
It is supported by contacting with.

The lower pipe 1 and the intermediate pipe 2 are connected to each other by connecting the upper flange 1b and the lower flange 2a with the spigot and bolt bolts]
~ 7, and the intermediate pipe 2 and the receiving cup 4 are assembled by fitting the outer periphery of the receiving cup 4 into the inside of the intermediate pipe 2, and tightening the upper flanges 2b and 4a of each other with bolts and nuts 7. . Figure 3 is a perspective view of the receiver cup 4, Figure 4 is a vertical cross-sectional view of the receiver without the cup 4, and Figure 5 is a vertical cross-sectional view of the bottom of the reactor, showing the scaffolding when installing the shroud. Figure 6 shows the state of Vl in Figure 5.
-Required in a cross-sectional view along the Vl line. Roughly speaking, Figure 7 is a vertical cross-sectional view of the bottom of the reactor, and does not show the state of the scaffolding when the core support plate was installed.

Next, the effect of the above configuration will be explained using the installation of the shroud 10 and the core support plate 12 in a reactor pressure vessel as an example. In principle, the present invention uses a plurality of scaffolds to install the scaffold, and normally, as shown in Fig. 4, the lower pipe 1 and the intermediate pipe 2 are fastened with bolts and nuts 7, and the upper pipe 3 is also connected to the intermediate pipe 2. Temporarily fix it to shorten the overall length and then transport it into the furnace. Of course, the size and weight of the unit may be reduced depending on the conditions of the entrance path and the installation location.

The scaffolding is first installed from the shroud 10 installation scaffold shown in FIG. Assemble the lower pipe 1, intermediate pipe 2, and upper pipe 3 as shown in FIG. , the protrusion of the lower flange 1a of the lower pipe 1 is fitted. The overall length of the assembled lower pipe 1 and intermediate pipe 2 is made in advance to match the height of the scaffolding for the shroud installation (=l).Next, the scaffolding board 6 is placed on the flange 3a of the upper bump 3. Fix it with bolts and nuts 7 to complete the scaffolding for installing the shroud.At this time, a reinforcing tool 8 having a fixing part 8b and an adjusting part 8a is passed between the adjacent lower pipe 1 and intermediate pipe 2 to reinforce it. This increases the rigidity of the entire scaffold and improves safety.Works such as welding the upper and lower parts of the shroud 10 and installing it on the shroud support 11 are performed using this scaffold.

Next, the scaffolding for installing the core support plate 12 is changed, but this involves adding roughly necessary members and scaffolding plates 6 according to the work content from the state of the shroud installation scaffold described above.
Alternatively, after the deletion, as shown in FIG. Lift it up to a height away from the upper flange 2b. While maintaining this state, the receiving cup 4 shown in FIG. 3 was separately carried into the reactor pressure vessel 1.
is fitted into the intermediate pipe 2 from above as shown in FIGS. 1 and 2, and the flange 4a is fixed to the upper flange 2b of the intermediate pipe 2 with bolts and nuts 7. After this, the hanging wire 14 of the crane is loosened, the upper pipe 3 is inserted into the cup 4, and the bottom part 3b is brought into contact with the bottom part 4b of the cup 4, thereby completing the process. The installation work of the core support plate 12 is performed using this scaffold. The lengths of the upper pipes 3 are all set in advance to be the same as the difference in height of the scaffolding for installing the shroud 10 and for installing the main core support plate 12.

To remove the scaffolding after the work is completed, either the members are temporarily assembled in the state shown in Figure 4 and transported out as a reverse process to the above, or each member is disassembled individually and transported in small pieces.

As mentioned above, all of the scaffolding members are small and easy to carry in and out of the site, and the scaffolding can be installed and moved in the order of work steps and quickly. Moreover, standardization of each member is easy.

Note that each member may be divided into a plurality of parts depending on the handling requirements such as its size, weight, etc., and may be used by appropriately connecting them.

FIG. 8 shows another embodiment, in which a plurality of holes 15 are provided on the side surfaces of the lower pipe 1 and the intermediate pipe 2, and the holes 15 are passed through the slots 16 to 16, and the scaffolding board 6 is attached to the upper part. The bottom portion 3b of the pipe 3 is abutted and supported. Also, by selecting the position of the hole 15 through which the stopper 16 passes,
The height of the scaffold board 6 can be selected variously. In this case as well, the operation and effect are the same as in the above-mentioned embodiment, but the cup 4 of FIG. 3 is not required, and the height of the scaffolding can be varied in various ways.

[Effects of the Invention] According to the present invention, temporary scaffolding used for installing a shroud, a core support plate, etc., which are internal structures of a large vessel such as a reactor pressure vessel, does not need to be installed for each work. Moreover, it is easy to carry in, carry out, and assemble, and has the effect of shortening the period required for installing internal structures.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the present invention, Fig. 2 is a longitudinal cross-sectional view of the receiver when the cup is in use, Fig. 3 is a perspective view of the cup with the receiver, Fig. 4 is a longitudinal cross-sectional view of the receiver without the cup, and Fig. 5 is a longitudinal cross-sectional view of the receiver without the cup. The figure is a vertical cross-sectional view of the bottom of the reactor, showing the shroud installed. Figure 6 is the Vl of Figure 5.
FIG. 7 is a vertical cross-sectional view of the bottom of the reactor when the core support plate is installed, and FIG. 8 is a vertical cross-sectional view of another embodiment. 1...Lower pipe, 1a, 2a...Lower flange, 1b, 2b, 3a, 4a...Upper flange, 2...
Middle pipe, 3... Upper pipe, 3b, 4b.
...Bottom, 4...Support is cup, 5...Stub tube of control rod drive mechanism, 6...Scaffold plate,
7... Bolt nut, 8... Reinforcement tool, 8
a...Adjustment part, 8b...Fixing part, 9...Reactor pressure vessel, 10...Shroud, 12...Reactor core support plate. Agent Patent Attorney Norio Ogo Figure 1 Figure 2 Figure 63α 7 Figure 4 Figure 3 Figure 5 Figure 6 Figure/4- Figure 7 Figure 8

Claims (1)

[Claims] a first member having a cylindrical shape and having at one end a flange that fits into a hole provided in the bottom of the container and a flange at the other end that connects to the second member; a second member having a flange connected to the member and a flange supporting a third member at the other end; and a cylindrical flange having a flange at one end to which a scaffolding board is attached; a third member that is insertable; and a cylindrical third member that is inserted therein;
The member is inserted into the second member, and has a flange that abuts the flange of the second member at one end and a bottom that abuts and supports the tip of the third member at the other end, and is fitted into the second member. 1. A scaffold for installing a structure inside a container, characterized by comprising a fourth member that allows