JP2002156484A - Manufacturing and installing method for base plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain installing accuracy in manufacturing and installing of a base plate and reduce transportation cost. SOLUTION: The ends of a plurality of arc shape plates 16 cut out of a material 17 are aligned and edge preparation is applied to the upper and lower surface sides of them. The edge preparation locations of the arc shape plates 16 are welded to form an annular plate 15, the inner and outer side surfaces of them are arranged and a hole 18 for inserting a bolt penetrating in the arc shape plate 16 in vertical direction. Then the inner and the outer side surfaces of neighboring arc shape plats 16 are mutually fixed with binding members 19 and 20, grinding is applied to the upper and lower side surfaces of the annular plate 15 and the welding layer between the arc shape plates 16 are removed. The fixation of the arc shape plates 16 with the binding members 19 and 20 is released, the arc shape plates 16 are independently carried to the installation site to reduce the pack shape. These arc shape plates 16 are set in turn on a pedestal 6 constructed in advance to form an annular base plate 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing and installing a base plate.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a structure for supporting a reactor pressure vessel.
And a skirt portion 5 extending downward from the lower end plate 2. The skirt portion 5 includes: The pressure vessel is placed on the upper end of a pedestal 6 erected in the reactor containment vessel via a base plate 7, and vertically protrudes upward from the pedestal 6, and penetrates through the base plate 7 and the flange 8 at the lower end of the skirt portion 5. The main body 3 is supported on the pedestal 6 so as to be located inside the reactor shield wall 10.

Conventionally, the manufacture and installation of the base plate 7 have been carried out according to the procedure shown in FIG.

[0004] First, an arc-shaped flat plate 12 having a shape obtained by dividing an annular flat plate 11 having an inner diameter and an outer diameter slightly larger than the base plate 7 to be manufactured into four parts is sufficiently cut off with respect to a design thickness t of the base plate 7. Material 13 for k
Cut out from

[0005] Next, the end face of each arc-shaped flat plate 12 is formed into a smooth shape, and beveling is performed on both upper and lower sides of the portion. Form.

Further, both inner and outer peripheral surfaces of the annular flat plate 11 are ground in accordance with the designed inner and outer diameters of the base plate 7, and holes 14 for inserting bolts 9 vertically penetrating the annular flat plate 11 are arranged at equal intervals in the circumferential direction. After the drilling, the upper and lower surfaces of the annular flat plate 11 are ground according to the design thickness t to form the base plate 7.

Further, the base plate 7 is transported to the installation site, and the bolts 9 are inserted through the respective holes 14.
The base plate 7 is placed on the already constructed pedestal 6.

At this time, a shim plate (not shown) for adjusting the height position is interposed between the pedestal 6 and the base plate 7 as necessary, so that the upper surface of the base plate 7 is kept horizontal. .

[0009]

The base plate 7 comprises:
Since it is a large structure with an outer diameter of about 6 to 9 m, the transportation of the base plate 7 from the manufacturing factory to the installation site has to use marine transportation means such as a ship or barge, and a great deal of transportation is required. Was expensive.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to maintain the installation accuracy and reduce the transportation cost when manufacturing and installing a base plate.

[0011]

According to a first aspect of the present invention, there is provided a method for manufacturing and installing a base plate, the method comprising the steps of: cutting a plurality of arc-shaped flat plates which can form an annular flat plate from a material; After flattening the end faces of the flat plates and performing beveling on the upper and lower surfaces thereof, welding the beveled portions of the arc-shaped flat plate to form an annular flat plate, trimming the inner and outer peripheral side surfaces of the annular flat plate and forming a circular plate After drilling a bolt hole vertically penetrating in each of the arc-shaped flat plates, the inner and outer peripheral sides of the adjacent arc-shaped flat plates are fixed to each other via a restraining member, and the upper and lower sides of the annular flat plate are ground. Then, the welding layer between the adjacent arc-shaped flat plates is removed, the arc-shaped flat plates are released from each other by the restraining member, and these arc-shaped flat plates are transported to the installation site, and the arc-shaped flat plates are sequentially placed on the pre-constructed slab. And annular base To form a rate.

In the method for manufacturing and installing a base plate according to a second aspect of the present invention, a plurality of arc-shaped flat plates that can form an annular flat plate are cut out from a material, the end faces of each of the arc-shaped flat plates are trimmed, and opened on both upper and lower surfaces thereof. After performing the pre-processing, the groove-formed portion of the arc-shaped flat plate is welded to form an annular flat plate, the inner and outer peripheral side surfaces of the annular flat plate are arranged, and bolt holes penetrating vertically through each of the arc-shaped flat plates. After drilling, the inner and outer peripheral sides of the adjacent arc-shaped flat plates are fixed to each other via a restraining member, and the upper and lower sides of the annular flat plate are subjected to grinding to remove a welding layer between the adjacent arc-shaped flat plates, The fixing of the arc-shaped flat plates by the restraining members is released, and these arc-shaped flat plates are conveyed to the installation site, the arc-shaped flat plates are connected at the installation site to form an annular base plate, and the base plate is formed on a previously constructed slab. It is installed.

In addition to the above, according to the method for manufacturing and installing a base plate according to the third aspect of the present invention, in forming an annular flat plate by welding a groove processed portion of an arc-shaped flat plate,
An adjusting plate is interposed between the opposed arc-shaped flat plates.

Furthermore, in the base plate manufacturing and mounting method according to the present invention, a notch extending vertically is provided at a predetermined position of each arc-shaped flat plate, and the notch protrudes upward and is slidably fitted. The guide member to be mounted is attached to the slab.

In any one of the first to fourth aspects of the present invention, the base plate to be mounted on the slab is transported to the installation site as a plurality of independent arc-shaped flat plates. And reduce the size of the package during transportation.

Before drilling a hole for inserting a bolt,
An adjusting plate is interposed between the arc-shaped flat plates to be welded and fixed to each other to secure a necessary clearance between the ends of the arc-shaped flat plates when placing on the slab.

Furthermore, when placing the arc-shaped flat plate on the slab, the notch of the arc-shaped flat plate is fitted to a guide member attached to the slab to guide the arc-shaped flat plate.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an embodiment of the method of manufacturing and installing a base plate according to the present invention. In the drawing, portions denoted by the same reference numerals as those in FIGS. 3 and 4 represent the same components.

In this method of manufacturing and installing a base plate, an arc-shaped flat plate 16 having a shape obtained by dividing an annular flat plate 15 having an inner diameter and an outer diameter slightly larger than the base plate 7 mounted on the pedestal 6 into four parts is formed into a design thickness t of the base plate 7. Is cut out from the material 17 with a sufficient cutting allowance k.

Next, the end face of each arc-shaped flat plate 16 is formed into a smooth shape, and beveling is performed on both upper and lower sides of the portion. Form.

At this time, an adjusting plate 21 having a thickness of about 1 to 2 mm is interposed between the opposite end faces of the arc-shaped flat plate 16.

The above-mentioned groove processing is performed so that, when the arc-shaped flat plates 16 are welded to each other, a portion corresponding to the design thickness t of the base plate 7 does not melt and a fusible material does not weld to the portion. It has been applied only to the cutting allowance k.

The inner and outer peripheral sides of the annular flat plate 15 are ground in accordance with the designed inner and outer diameters of the base plate 7, and holes 18 for bolts 9 penetrating vertically through the annular flat plate 15 are formed at equal intervals in the circumferential direction. Drill.

Then, the arc-shaped flat plates 16 are fixed to each other by bolting or tack-welding the restraining members 19 and 20 to both sides of the inner and outer circumferences of the ends of the adjacent arc-shaped flat plates 16. The upper and lower surfaces 15 are ground according to the design thickness t to form the base plate 7.

The thickness of the restraining members 19 and 20 is set to be equal to or less than the design thickness t of the base plate 7, and the above-described grinding removes the welding layer between the ends of the adjacent arc-shaped flat plates 16. Become.

Further, after the mutual connection of the arc-shaped flat plates 16 by the restraining members 19 and 20 is released, and the adjusting plate 21 is removed from between the end faces of the arc-shaped flat plates 16, these arc-shaped flat plates 16 are connected to a trailer truck or the like. By land transportation,
Transported from the production plant to the installation site.

When the arc-shaped flat plate 16 is transported to the installation site, the bolts 9 are inserted into the respective holes 18 so as to be inserted.
The pedestal 6 already constructed with the arc-shaped flat plate 16
An annular base plate 7 is formed by sequentially placing the base plates 7 on the upper surface.

At this time, the pedestal 6 and each arc-shaped flat plate 1
6, a shim plate (not shown) for height position adjustment is interposed as required.

Further, when the holes 18 for inserting the bolts 9 are formed in the annular flat plate 15, holes which penetrate vertically so as to straddle both of the adjacent arc-shaped flat plates 16 are formed. A notch 22 is provided at an end of the arc-shaped flat plate 16 as shown in FIG.
A guide member 23 may be attached to the pedestal 6 so as to protrude upward and the notch portion 22 slidably fit therein, and the arc-shaped flat plate 16 to be placed on the pedestal 6 may be guided by the guide member 23.

In this case, the arc-shaped flat plate 16 is
After the base plate 7 (see FIG. 1) is sequentially placed on the base plate 7 (see FIG. 1), the guide member 23 is removed or the guide member 23 is cut so as not to protrude upward from the base plate 7. 3 avoids interference with the accompanying flange 8.

Further, the base plate 7 is formed by connecting the arc-shaped flat plates 16 at the installation site using the above-described restraining members 19 and 20, and the base plate 7 is placed on the pedestal 6. Is also good.

As described above, in the base plate manufacturing and installation method of the present invention shown in FIGS. 1 and 2, the base plate 7 to be mounted on the pedestal 6 is transported to the installation site as a plurality of independent arc-shaped flat plates 16 respectively. In this way, the size of the package at the time of transportation is reduced, so that land transportation means such as a trailer truck can be used, and transportation costs can be reduced as compared with the related art.

Before drilling the holes 18 for inserting the bolts 9, the adjusting plate 21 is interposed between the circular arc-shaped flat plates 16 to be welded and fixed to each other, so that the adjusting plate 21 is placed on the pedestal 6. Since the required clearance is secured between the ends of the flat plate 16, it is possible to avoid the ends of the arc-shaped flat plate 16 from overlapping while maintaining the installation accuracy.

Further, when placing the arc-shaped flat plate 16 on the pedestal 6, the notch 22 of the arc-shaped flat plate 16 is fitted into the guide member 23 attached to the pedestal 6, and the arc-shaped flat plate 16 is guided. Therefore, the alignment between the hole 18 and the bolt 9 can be performed easily and reliably.

The method of manufacturing and installing a base plate according to the present invention is not limited to the above-described embodiment, but may be modified without departing from the spirit of the present invention.

[0037]

As described above, according to the method of manufacturing and installing a base plate of the present invention, various excellent effects as described below can be obtained.

(1) The base plate to be placed on the slab is transported to the installation site as a plurality of arc-shaped flat plates to reduce the size of the package during transportation. It becomes possible to use it, and the transportation cost can be reduced as compared with the related art.

(2) Before drilling a hole for bolt insertion, an adjusting plate is interposed between the arc-shaped flat plates to be welded and fixed to each other, and the end of the arc-shaped flat plate is placed on the slab. Since the necessary clearance is secured between the parts, it is possible to avoid the ends of the arc-shaped flat plates from overlapping while maintaining the installation accuracy.

(3) Further, when the arc-shaped flat plate is placed on the slab, the notch of the arc-shaped flat plate is fitted to the guide member attached to the slab to guide the arc-shaped flat plate. And the bolt can be easily and reliably aligned.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a procedure of an example of an embodiment of a base plate manufacturing and installation method of the present invention.

FIG. 2 is a conceptual diagram showing a relationship between a notch provided in an arc-shaped flat plate and a guide member attached to a pedestal.

FIG. 3 is a conceptual diagram showing an example of a reactor pressure vessel support structure.

FIG. 4 is a conceptual diagram showing a procedure of an example of a conventional base plate manufacturing and installation method.

[Explanation of symbols]

 Reference Signs List 6 pedestal (slab) 7 base plate 15 annular flat plate 16 arc-shaped flat plate 17 material 18 hole (bolt hole) 19 restraining member 20 restraining member 21 adjusting plate 22 notch portion 23 guide member

Claims (4)

[Claims] 1. A plurality of arc-shaped flat plates that can form an annular flat plate are cut out from a raw material, the end faces of each of the arc-shaped flat plates are trimmed, and beveling is performed on both upper and lower surfaces thereof. After forming the annular flat plate by welding the processing locations, trimming the inner and outer peripheral sides of the annular flat plate, drilling bolt holes vertically penetrating each of the arc-shaped flat plates, and then forming the inner and outer circumferences of the adjacent arc-shaped flat plates Both sides are fixed to each other via the restraining member, and the upper and lower sides of the annular flat plate are subjected to grinding to remove a welding layer between the adjacent arc-shaped flat plates, and the fixing of the arc-shaped flat plates to each other by the restraining member is released. A method for installing and manufacturing a base plate, comprising transporting these arc-shaped flat plates to an installation site and sequentially setting the arc-shaped flat plates on a pre-constructed slab to form an annular base plate. 2. A plurality of arc-shaped flat plates that can form an annular flat plate are cut out from a raw material, the end faces of each of the arc-shaped flat plates are trimmed, and both upper and lower sides thereof are beveled. After forming the annular flat plate by welding the processing locations, trimming the inner and outer peripheral sides of the annular flat plate, drilling bolt holes vertically penetrating each of the arc-shaped flat plates, and then forming the inner and outer circumferences of the adjacent arc-shaped flat plates Both sides are fixed to each other via the restraining member, and the upper and lower sides of the annular flat plate are subjected to grinding to remove a welding layer between the adjacent arc-shaped flat plates, and the fixing of the arc-shaped flat plates to each other by the restraining member is released. A method of installing a base plate, comprising transporting these arc-shaped flat plates to an installation site, connecting the arc-shaped flat plates at the installation site, forming an annular base plate, and installing the base plate on a pre-constructed slab. 3. An adjusting plate is interposed between opposing arc-shaped flat plates in forming an annular flat plate by welding a groove-processed portion of the arc-shaped flat plate.
The method for manufacturing and installing a base plate according to any one of the above. 4. A notch extending in a vertical direction at a predetermined position of each arc-shaped flat plate, and a guide member protruding upward and fitting the notch slidably is attached to the slab. 3. The method for manufacturing and installing a base plate according to any one of 3.