JP2005292063A5

JP2005292063A5 -

Info

Publication number: JP2005292063A5
Application number: JP2004110636A
Authority: JP
Filing date: 2004-04-05
Publication date: 2007-05-31
Anticipated expiration: 2024-04-05

Claims

A fixed portion mounted on the outer peripheral surface so that the inner peripheral surface surrounds the outer peripheral surface of the radioactively contaminated cylindrical structure, and an outer periphery of the cylindrical structure that is rotatably supported by the fixed portion and driven by power Using a cutting machine comprising a rotating part that rotates around a surface, a tool post mounted on the rotating part, and a cutting tool mounted on the tool post,
A cutting blade is inserted from the opening end of the cylindrical structure so that the cutting blade faces the inner peripheral surface of the cylindrical structure, the rotating portion is rotated, and the cutting blade is moved to the axis of the cylindrical structure. Cutting the inner peripheral surface of the cylindrical structure with the cutting blade by sending in the direction to decontaminate the inner peripheral surface,
A cutting blade is made to face the outer peripheral surface of the cylindrical structure, the rotating portion is rotated, and the cutting blade is fed inward in the radial direction of the cylindrical structure so that the cylindrical structure is moved by the cutting blade. A method for decontamination and disassembly of a cylindrical structure in which the cylindrical structure is disassembled by cutting and cutting from the outside ,
When performing decontamination of the inner peripheral surface, as the tool post, a cutting tool is inserted from the opening end of the cylindrical structure so that the cutting tool faces the inner peripheral surface of the cylindrical structure, and Using an inner peripheral surface cutting tool post capable of sending a cutting tool in the axial direction of the cylindrical structure,
When the dismantling is performed, as the tool rest, the cutting tool is used for cutting an outer peripheral surface which allows the cutting tool to face the outer peripheral surface of the cylindrical structure and feed the cutting tool in the radially inward direction of the cylindrical structure. Use the tool post,
Performing the decontamination over a predetermined width in the axial direction from the opening end of the cylindrical structure on the inner peripheral surface of the cylindrical structure,
After the decontamination, the mounting position of the fixed portion of the cutting machine with respect to the outer peripheral surface of the cylindrical structure is set to the back side in the axial direction from the planned cutting position set at the position where the inner peripheral surface has been decontaminated. To perform the cutting at the planned cutting position,
After the cutting, the removal position of the fixed portion of the cutting machine remains unchanged, and the inner peripheral surface of the cylindrical structure is removed from the new opening end of the cylindrical structure over a predetermined width in the axial direction. A method for decontamination and disassembly of a cylindrical structure for dyeing.

The decontamination step, the moving step of the fixed part, decontamination and dismantling method according to claim 1 cylindrical structure according to repeat as appropriate number of cycles of the cutting process.

A method for decontaminating and dismantling a heat exchanger in which the inside of a cylindrical main body is radioactively contaminated,
A fixed portion mounted on the outer peripheral surface so as to surround the outer peripheral surface of the main body barrel; a rotating portion that is rotatably supported by the fixed portion and rotates around the outer peripheral surface of the main body barrel by power; and the rotation Using a cutting machine equipped with a tool post mounted on the part and a cutting tool mounted on the tool post,
Attach the fixed part of the cutting machine to the position on the side of the main body barrel, which is behind the tube sheet, on which the heat transfer tube bundle is disposed,
Use of an outer peripheral surface cutting tool post that allows the cutting tool to face the outer peripheral surface of the main body cylinder and feed the cutting tool radially inward of the main body cylinder as the tool post, and the mounting position of the fixed portion And a position of the tube sheet between the cutting edge and the outer peripheral surface of the main body cylinder, the cutting blade is rotated, and the rotating portion is rotated and the cutting blade is sent inward in the radial direction of the main body cylinder. Cutting the main body barrel from the outside with a cutting blade and cutting it,
After the cutting, the heat transfer tube bundle is extracted from the main body body together with the tube plate,
After the extraction, the mounting position of the fixed part is left as it is, and the cutting tool is inserted from the opening end formed by cutting the main body cylinder as the tool post so that the cutting tool faces the inner peripheral surface of the main body cylinder. And using an inner peripheral surface cutting turret capable of feeding the cutting tool in the axial direction of the main body cylinder, inserting the cutting tool from the opening end of the main body cylinder, and inserting the cutting tool into the inner side of the main body cylinder. Decontamination of the inner peripheral surface by cutting the inner peripheral surface of the main body cylinder with the cutting blade by causing the cutting blade to face the peripheral surface, rotating the rotating portion and sending the cutting blade in the axial direction of the main body cylinder Over a predetermined width in the axial direction from the opening end,
After the decontamination, the mounting position of the fixed portion of the cutting machine with respect to the outer peripheral surface of the main body cylinder is set to the back side in the axial direction from the next scheduled cutting position set to the position where the inner peripheral surface has been decontaminated And using the outer peripheral surface cutting tool post, causing the cutting tool to face the outer peripheral surface of the main body cylinder at the planned cutting position, rotating the rotating portion and causing the cutting tool to move in the radial direction of the main body cylinder. Cutting the main body cylinder from the outside with the cutting blade by sending it inwardly,
After the cutting, the mounting position of the fixed part is kept as it is, and the cutting tool for cutting the inner peripheral surface is used, and the cutting tool is inserted from a new opening end of the main body cylinder so that the cutting tool is inserted into the main body cylinder. Decontamination of the inner peripheral surface by cutting the inner peripheral surface of the main body cylinder with the cutting blade by causing the cutting blade to face the peripheral surface, rotating the rotating portion and sending the cutting blade in the axial direction of the main body cylinder Over a predetermined width in the axial depth direction from the new opening end,
Thereafter, a method for decontamination and dismantling of a cylindrical structure in which a cycle of the fixing part moving step, cutting step, and decontamination step is repeated as appropriate.

4. The decontamination and dismantling of the cylindrical structure according to claim 3, wherein the extracted heat transfer tube bundle is cut and separated into individual heat transfer tubes, and the outer peripheral surface and the inner peripheral surface are decontaminated for each heat transfer tube. Method.