JPH02234096A - Assembling and transporting method for nuclear pressure vessel and transport use truck - Google Patents

Abstract

PURPOSE:To simplify the job site work and to shorten the construction process by attaching integrally an in-nuclear reactor recirculating pump casing to a nuclear pressure vessel body in advance in a plant, and attaching, a temporary skirt for containing and protecting its casing. CONSTITUTION:In a plant, an in-nuclear reactor recirculating pump casing 7 is attached integrally to a reactor pressure vessel 1 body, and reamer working of a fitting part and other finish working are executed. Subsequently, one end of a temporary skirt 15 having sufficient length for containing and protecting the casing 7 is attached to a skirt flange 4a of the vessel 1, and the other end is supported by a supporting leg 17 provided on a transport use truck 16. Also, a drum flange 3 part of the vessel 1 is supported by a supporting leg 18. In such a way, in a state that the vessel 1 is placed and fixed on the truck 16, the track 16 is run, and the vessel 1 is transported to a setting job site. Moreover, a support 19 is provided by projecting it from the inside surface of the skirt 15, by which the casing 7 is supported, and the deformation and damage caused by its dead weight are prevented.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Field of Application) The present invention relates to a method for assembling and transporting a reactor pressure vessel of a boiling water reactor (BWR), and a transportation trolley, and particularly relates to a The present invention relates to a method for assembling and transporting a nuclear reactor pressure vessel, which can simplify the transport process of transporting the vessel to the installation site, and can greatly simplify the assembly work at the installation site, and a transport trolley used during the transport.

(Prior Art) Conventionally, a nuclear reactor pressure vessel 1 generally has a free-standing rigid cylindrical shape as shown in FIG. 2, and is supported on a support skirt 2 disposed at the bottom thereof. A thick-walled shell 7 flange 3 is formed at the top of the reactor pressure vessel 1, and a skirt flange 4 is attached to the bottom of the support skirt 2.

Additionally, an external recirculation loop (P
A recirculation nozzle 5 is provided which connects to LR). The external recirculation loop pumps the reactor coolant through a jet pump located inside the reactor! It is a system that circulates I1,
It consists of multiple independent loops, each of which is fitted with a volute recirculation pump.

In the conventional reactor pressure vessel 1 in which the external recirculation loop (PLR) as described above is assembled at the installation site, after the vessel body is assembled in the manufacturing factory, final annealing is performed and the recirculation nozzle 5 is welded. It was loaded onto a transport trolley or ship in a lying position and transported to the installation site.

This conventional reactor pressure vessel 1 has a substantially cylindrical shape and has few nozzles protruding from the side wall of the vessel body or the cylindrical support skirt 2, so it is easy to handle during transportation. That is, the reactor pressure vessel 1 was fixed to a transportation trolley via supporting S structures at the skirt flange 4 and the trunk flange 3 formed at the top, respectively, and was transported to an installation site.

However, in recent years, in order to simplify the structure of the recirculation system by abolishing the recirculation loop that was installed outside the reactor pressure vessel 1, the recirculation pump has been installed at the bottom edge of the reactor pressure vessel 1. Reactor-integrated recirculation bombs (RIPs), which are integrally equipped, are increasingly being adopted.

A plurality of reactor built-in re-WJ ring pumps (RIPs) are mounted on the outer periphery of the lower chain plate 6 of the reactor pressure vessel 1, as shown in FIG. Conventionally, the pump casing 7 of this recirculation bomb is arranged so as to protrude significantly below the lower base plate 6 at the installation site. Further, an expanded support skirt 2a is formed on the side wall of the pressure vessel 1.
A skirt flange 4a is disposed at the lower end of a.

As shown in FIG. 4, the upper end of the pump casing 7 is fitted into a mounting nozzle 8 formed in the lower end plate 6 of the reactor pressure vessel 1, and is fixed together by welding. Since the rotating shaft of the recirculation bomb that rotates at high speed is inserted into the mounting nozzle 8 including this welded joint 9, the welded joint 9
After welding, the mounting nozzle 8 is reamed, keyed grooved, etc., and finished with high precision.

(Problem to be Solved by the Invention) However, since the pump casing 7 of the recirculation pump has a shape that largely protrudes from the bottom of the reactor pressure vessel 1, it is necessary to provide curing to protect it from deformation and excommunication during transportation. was difficult. Therefore, conventionally, the reactor pressure vessel 1 and the pump casing 7 were delivered to the site by separate delivery.
At the installation site, the pump casing 7 was installed and processed and adjusted.

However, at the stage when the reactor pressure vessel 1 is installed in the reactor containment vessel at the site, as shown in Figure 5, many equipment assembly works are carried out in parallel, making the assembly process complicated and difficult to proceed smoothly. There is a problem that assembly work cannot be carried out.

In other words, considering the overall construction process of the reactor equipment and the work efficiency in the working space below the reactor pressure vessel 1, when the reactor pressure vessel 1 is installed on site, the control rod drive mechanism (CRD) The piping 11, the recirculation bomb exchanger 12, the structures 13, etc. that are disposed around the locations where the pump casing 7 will be attached must have already been delivered and installed.

Even if the installation of all these devices has been completed, the pump casings 7 for more than ten pumps are inserted into the installation nozzle 8 of the reactor pressure vessel 1 in the narrow lower drywell 10, and then the centering position is Performing finishing work such as welding and rough reaming after company approval involves many difficulties. There is also a risk that the work process will be extremely complicated due to am loading equipment planning, installation of centering support equipment, etc., and the construction period will be delayed.

Also, when performing welding and machining work between the pump casing 7 and the mounting nozzle 8. 1 reactor pressure capacity i21
1. It is necessary for a worker to approach from inside. However, since there is no recirculation nozzle in the reactor pressure vessel 1 which does not have an external recirculation loop (PLR), the operator must open the opening of the shell flange 3 at the top of the reactor pressure vessel 1,
It is impossible to enter or exit the reactor pressure vessel 1 other than through the gap between the reactor pressure vessel 1 and the core shroud 14, which poses the problem of extremely poor workability.

Furthermore, when the pump casing 7 is shipped separately and assembled into the reactor pressure vessel 1 on site as in the past, other work must be completed in the lower dry well 10 before the hydraulic pressure test of the reactor pressure vessel 1. Considering this relationship, it is desirable to carry out work on the pump casing 7 immediately after the installation of the reactor pressure vessel 1 is completed, prior to work on other peripheral equipment. However, at this point, the reactor building housing the reactor pressure vessel 1 is under construction, so the accessibility for workers from outside the building to the 3 part of the flange 7 of the reactor pressure vessel 1 is poor.

Furthermore, in the past, the pump casing 7 and the mechanical equipment required for processing the pump casing 7 were transported to the site separately from the reactor pressure vessel main body, which caused the problem that the transportation process was complicated.

The present invention has been made to solve the above problems, and it simplifies the transportation process of transporting the reactor recirculation pump (RIP) casing and the reactor pressure vessel to the installation site, and also simplifies the assembly process at the installation site. An object of the present invention is to provide a method for assembling and transporting a nuclear reactor pressure vessel that can greatly simplify the work, and a transport platform used during the transport.

[Structure of the invention]

<<Means for Solving the Problems>> In order to achieve the above object, the method for assembling and transporting a reactor pressure vessel according to the present invention includes integrally attaching the reactor recirculation pump casing to the reactor pressure vessel main body in advance in a factory. , After the finishing process, a temporary scar 1.
One end of the temporary skirt is attached to the reactor pressure vessel skirt flange, and the other end is supported by the support legs provided on the transport trolley, and the transport trolley is driven to the reactor pressure vessel installation site. It is characterized by being transported.

Further, the reactor pressure vessel transportation trolley according to the present invention is a transportation trolley for transporting a reactor pressure vessel to which a reactor recirculation pump casing is integrally attached, in which the reactor recirculation pump casing is housed and protected. It has a sufficient length for
It is characterized by being equipped with a temporary skirt.

<<Operation>> According to the method for assembling and transporting a reactor pressure vessel according to the above configuration, the reactor recirculation pump casing is preliminarily installed integrally with the reactor pressure vessel in a factory with an excellent working environment, and is also subjected to finishing processing. Since this has been implemented, on-site installation work and finishing work can be omitted, significantly simplifying on-site work.

Furthermore, the temporary skirt, which is long enough to house and protect the pump casing installed at the factory, can effectively prevent deformation and damage during transportation.

In general, the transportation trolley according to the present invention makes it possible to transport the pump casing at the same time as the reactor pressure vessel body, instead of transporting the pump casing and the equipment required for finishing it separately, as in the past. compared to if
The transportation process for equipment can be greatly simplified.

(Example) An example of the present invention will be described below with reference to the attached drawings 4-J. FIG. 1 is a side view showing a state in which a nuclear reactor pressure vessel is transported using the method of the present invention and a transport trolley. In addition, as shown in FIGS. 2 to 5, elements that are the same as those of the conventional example are given the same numbers.

That is, in the method for assembling and transporting the reactor pressure vessel according to this embodiment, first, the reactor recirculation pump casing 7 is assembled into the reactor pressure vessel in advance at the factory. 1 After installing it in one body and performing finishing processes such as reaming and keyway machining on the mounting part,
A temporary skirt 15 having a length sufficient to house and protect the reactor recirculation pump casing 7 is prepared, one end of the temporary skirt 15 is attached to the skirt flange 4a of the reactor pressure vessel 1, and the other end is attached to the skirt flange 4a of the reactor pressure vessel 1. The transport trolley 16 is supported by support legs 17 provided on the transport trolley 16, and the trunk flange 3 of the reactor pressure vessel 1 is supported by the support legs 18, and the transport trolley 16 is run to transport the reactor recirculation pump casing 7.
The reactor pressure vessel 1, which has been assembled into one piece, is transported to the installation site.

Further, a suitable transport trolley 16 used during transportation is a transport trolley 16 for transporting the reactor pressure vessel 1 to which the reactor recirculation pump casing 7 is integrally attached. The skirt flange 4a of the reactor pressure vessel 1 has sufficient properties for storage and protection.
It is equipped with a temporary skirt 15 that can be taken off.

The temporary skirt 15 is formed into a cylindrical shape and has a length sufficient to accommodate the pump casing 7 protruding from the skirt flange 4a of the reactor pressure vessel 1.

When transporting the reactor pressure vessel 1 with the pump casing 7 joined together and finished at the factory, first attach one end of the temporary skirt 15 to the skirt flange 4a, and then attach a support leg to the sacrum end of the temporary skirt 15. 17 is attached, and support legs 18 are also attached to the body flange 311, and the carrier is mounted and fixed on the transportation truck 16 via a pair of support legs 17 and 18 provided on the transportation truck.

Note that the joint between the skirt flange 4a and the temporary skirt 15, the joint between the temporary skirt 15 and the support leg 17, and the joint between the body flange 3 and the support leg 18 are made to have an airtight structure.
By filling the inside with nitrogen gas, etc., it is possible to prevent rust during transportation.

In addition, as a protection measure during transportation of the pump casing 7 protruding from the bottom of the reactor pressure vessel 1, a temporary skirt 15 is installed.
It is also possible to provide a support 19 protruding from the inner surface and support the pump casing 7 by the support support 19 to prevent deformation or damage due to its own weight.

As described above, according to the method for assembling and transporting a nuclear reactor pressure vessel according to this embodiment, the reactor recirculation pump casing 7 is integrally attached to the reactor pressure vessel 1 in advance at a factory, and the final processing is carried out. Since it is delivered to the installation site at the top, it is possible to omit the installation process on site, which eliminates the poor workability caused by the narrow working space at the bottom of the reactor pressure vessel, and significantly simplifies the on-site work. be able to.

Further, the protruding pump casing 7 is protected by a temporary skirt 15 during transportation, and deformation and damage during transportation are effectively prevented.

Furthermore, according to the transportation trolley 16 according to this embodiment, it is possible to transport the pump casing 7 at the same time as the reactor pressure vessel 1 body, and unlike the conventional method, the pump casing 7 and the equipment required for its finishing can be transported separately. Compared to the case where the equipment was transported by , the shipping and return of the equipment is also omitted, which greatly simplifies the transportation process.

In addition, reactor pressure vessel 1 may be used at factories, ports, installation sites, etc.
As long as there is no effect due to increased heavy ffi due to the equipment specifications of the III aircraft, transportation vessel, trailer, etc. to be handled, other structures installed inside the reactor pressure vessel 1a1, such as the core shroud 14 shown in FIG. It is also possible to install them in advance at the factory and transport them to the site.

〔Effect of the invention〕

As explained above, according to the method for assembling and transporting a reactor pressure vessel according to the present invention, the reactor recirculation pump casing is previously integrally attached to the reactor pressure vessel in a factory with an excellent working environment, and Since the process has been carried out, on-site installation work and finishing work can be omitted, significantly simplifying on-site work, and having a significant effect on shortening the construction process and improving safety.

In addition, the temporary skirt, which is strong enough to house and protect the pump casing installed at the factory, can effectively prevent deformation and damage during transportation.

Furthermore, according to the transportation trolley of the present invention, it is possible to transport the pump casing at the same time as the reactor pressure vessel main body, and unlike conventional methods, the pump casing and the equipment required for its finishing were transported separately. Compared to the case
The transportation process for equipment can be greatly simplified.

[Brief explanation of drawings]

FIG. 1 is a side view showing a state in which a reactor pressure vessel is being transported using a transportation trolley according to the present invention, and FIG. 2 is a side view of a conventional reactor pressure vessel connected to an external recirculation loop. Figure 3 is a vertical cross-sectional view of the reactor pressure vessel equipped with a recirculation pump built into the reactor, Figure 4 is a cross-sectional view showing the mounting structure of the pump casing, and Figure 5 is a cross-sectional view of the reactor pressure vessel equipped with a recirculation pump built into the reactor. FIG. 2 is a cross-sectional view showing the reactor pressure vessel and its surrounding area. DESCRIPTION OF SYMBOLS 1... Reactor pressure vessel, 2.28... Support skirt, 3... Trunk 7 flange, 4, 4a... Skirt flange, 5... Recirculation nozzle, 6... Lower end plate, 7...
・Pump casing, 8... Mounting nozzle, 9... Welding joint, 10... Lower dry well, 11... Piping for control rod drive mechanism, 12... Recirculation bomb exchanger,
13... Structure, 14... Core shroud, 15.
...Temporary skirt, 16...Transportation trolley, 17...Support leg, 18...Support leg, 19...Support support. famous giant sheep

Claims (1)

[Claims] 1. After the reactor recirculation pump casing has been integrally attached to the reactor pressure vessel main body in advance at the factory and finishing processing is performed, the reactor recirculation pump casing is sufficiently housed and protected. A temporary skirt with a certain length is prepared, one end of the temporary skirt is attached to the reactor pressure vessel skirt flange, and the other end is supported by a support leg provided on the transport trolley, and the transport trolley is run. A method for assembling and transporting a reactor pressure vessel characterized by transporting the reactor pressure vessel to an installation site. 2. A transportation trolley for transporting the reactor pressure vessel to which the reactor recirculation pump casing is integrally attached, has a length sufficient to house and protect the reactor recirculation pump casing, and has a length sufficient to accommodate and protect the reactor recirculation pump casing, and the reactor pressure vessel is A transportation trolley characterized by being equipped with a removable temporary skirt on the skirt flange of a container.