JPH10111378A - Installation method of cylindrical structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position a welding opening tip part as a reference and perform open-tip alignment of welding with high precision by setting a guide device having an arbitrary number of upwardly oriented tapered parts at a predetermined installation part and letting a cylindrical structure sit by suspending it from above. SOLUTION: A platform 4 for fixing guide devices 5 is set on a top face of a housing 3. The guide devices 5 is disposed at four parts at intervals of 90 degrees at an outer rib of this platform 4. An upwardly oriented taper is disposed on a top part of the guide devices 5. At an outer end of the guide devices 5, a shroud 1 (cylindrical structure) is placed matching a position of a lower end inner face of the shroud 1 when placed in a specified installation site on a shroud support 2 (cylindrical support structure). Thereby, the shroud 1 is lowered from above in vertical direction and is sit on the shroud support 2, and at the same time installation can be performed at a correct position. That is, the cylindrical structure can be installed by remote control with high precision on the cylindrical support structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for remotely mounting a cylindrical structure on a cylindrical support structure at a predetermined position with high precision.

[0002]

2. Description of the Related Art Conventionally, as an example of remotely installing a cylindrical structure on a cylindrical support structure, a cylindrical internal structure (hereinafter, referred to as a shroud) which is a nuclear reactor internal structure has been used.
There is installation on the cylindrical support structure (referred to as a shroud support cylinder). As described in JP-A-63-36195, after the existing shroud is cut and removed, a new shroud is installed with a remote-operated core measuring device. There has been proposed a method of measuring the amount of misalignment of a center line connecting a center of a target installed on a center stub tube of a container and installing the same on the existing shroud support cylinder while performing arithmetic processing.

[0003]

However, the new shroud support is attached to the existing shroud support cylinder by welding, but no consideration is given to the alignment of the welded portion.

[0004] An object of the present invention is to provide an installation method capable of positioning a welding groove with high precision by positioning the welding groove portion as a reference.

[0005]

According to the present invention, there is provided a method of installing a cylindrical structure, comprising the steps of: providing a guide device having a tapered portion facing upward in order to achieve the above object; and providing a guide device inside or outside the shroud or both sides thereof. By attaching an arbitrary number, the shroud can be suspended from above and can be seated at a predetermined position. Further, by providing the guide device with an adjusting mechanism in the radial direction and the circumferential direction, the installation accuracy can be improved.

By the guide device, the lower end of the shroud comes in contact with the shroud while it is suspended, and the lower end of the shroud can be physically guided to a predetermined position on the shroud support.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) A first embodiment will be described below with reference to FIGS.

A guide device 5 is provided on the upper surface of the CRD housing 3.
A platform 4 is provided for fixing. As shown in FIG. 2, guide devices 5 are arranged at four locations at 90 ° intervals on the outer edge of the platform 4. The upper part of the guide device 5 is provided with a taper facing the lower part of the reactor pressure vessel 6, and the outer end of the guide device 5 has a shroud 1 at a predetermined installation place on the shroud support 2. The lower end of the shroud 1 is positioned in accordance with the position.

According to this embodiment, the shroud 1 can be lowered in the vertical direction and seated on the shroud support 2, and at the same time, can be installed at a correct position.

(Embodiment 2) A second embodiment will be described with reference to FIGS.

On the upper surface of the CRD housing 3, a swing platform 7 for fixing the movable guide device 10 is provided. The turning platform 7 is fixed to the CRD housing 3. It is composed of a fixed base 7a, a turning section 7b, and a drive section 7c fixed to the fixed base 7a and turning the turning section 7b. The drive section 7c is connected to the control device 8 by a cable 9. As shown in FIG. 4, movable guide devices 10 are arranged at four positions at 90 ° intervals at the outer end of the turning portion 7b.
The upper part of the movable guide device 10 is provided with a taper facing the lower part of the reactor pressure vessel 6.
The outer end of the shroud 1 is located in accordance with the position of the inner surface of the lower end of the shroud 1 when the shroud 1 is placed at a predetermined installation place on the shroud support 2. Movable guide device 1
0 includes a head unit 10a and a driving unit 10b that drives the head unit 10a in the radial direction.
b is connected to the control device 8 by a cable 9. According to the present embodiment, the shroud 1 can be lowered in the vertical direction and seated on the shroud support 2 and can be installed at the correct position at the same time. By driving the device 10 and the turning platform 7 by the control device 8, it is possible to adjust the position to a correct position.

[0012]

According to the present invention, when the internal structure of the cylindrical furnace is remotely installed on the cylindrical support structure, high-precision installation can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which a shroud is installed on a shroud support.

FIG. 2 is a conceptual diagram showing an example of the arrangement of a guide device guide unit.

FIG. 3 is a conceptual side view of a case where a guide unit guide is movable in a radial direction or a circumferential direction.

FIG. 4 is a conceptual cross-sectional view in a case where a guide device guide portion is movable in a radial direction or a circumferential direction.

[Explanation of symbols]

1: Shroud, 2: Shroud support, 3: CRD
Housing, 4 ... Platform, 5 ... Guiding device, 6 ...
Reactor pressure vessel, 7: swivel platform, 7a: fixed base, 7b: swivel unit, 7c: drive unit, 8: control device, 9 ...
Cable, 10: movable guide device, 10a: head unit, 1
0b: Drive unit.

Claims (2)

[Claims] When a cylindrical structure is installed vertically and concentrically, an arbitrary number of guide devices having a tapered portion facing the upper surface are installed inside and / or outside a portion to be installed, and the cylindrical structure is placed on an upper portion. A method of installing a cylindrical structure, comprising: suspending a vehicle from a crane and seating it at a predetermined position. 2. The method according to claim 1, wherein the guide device is movable in a radial direction and a circumferential direction independently or in conjunction with each other.