Background
For more than 35 years, Westinghouse has cut reactor vessel internals. For some plants, this was done in the frame of reactor pressure vessel internals (RPVIs) replacement as part
of life-cycle extension programs. In some other cases, Westinghouse cut internals in plants under decommissioning. The underwater mechanical cutting technique has been used in all boiling water reactors (BWRs) since 1999.
Description
Westinghouse systems allow highly irradiated
RPVIs to be safely removed, segmented and disposed of in storage buildings. The Westinghouse concept is based on clean, safe and reliable techniques. All segmentation work performed with mechanical cutting complies with nuclear power plant requirements.
Disc saw (Olkiluoto 1, 2009)
Band saw (Oskarshamn 2, 2004)
Benefits
There are three important factors for both the customer and Westinghouse to keep in mind during the implementation of RPVI segmentation:
- Safety of the personnel and the plant
- Cleanliness of the environment
- Minimization of the total dismantling, disposal and storage costs
Westinghouse has developed segmentation techniques based on mechanical cutting with different band saws, disc saws, tube cutters and shearing tools. The benefits of these techniques include the following:
- Minimal amount of secondary waste
- Full visibility during cutting
- Easy collection of chips from the cutting process
- No production of gas or airborne contaminants
- Customization of all RPVI part sizes, materials and thicknesses
- Safe and reliable techniques
All segmentation projects have been performed with the highest customer satisfaction. Westinghouse’s mechanical cutting technique is also well-suited for segmentation of RPVIs.
Experience
Westinghouse experience in segmentation RPVI projects is listed in the table below.
