Method of segmenting irradiated boiling water reactor control rod blades
View Patent ↗A method of reducing the volume of a blade section of a boiling water reactor control rod for transport or storage that cuts the control rod spline into four substantially equal longitudinal sections, with each longitudinal section including one control rod blade. Each longitudinal section is radiologically characterized and the locations of desired lateral segmentation are identified. A band of malleable metal is wrapped around each longitudinal section at each of the locations and the bands are sheared to separate segments of the longitudinal section and the ends of the bands are crimped at the point of shearing to seal the interior of the segments.
1. A method of reducing the storage volume of a boiling water reactor control rod having a main control element with four panels radially extending along an elongated length of a central spline, at four ninety degree locations around a circumference of the spline, in a cruciform shape, comprising the steps of:
separating the spline along its elongated length into four substantially equal longitudinal sections with each longitudinal section including one of the panels;
identifying at least one elevation along a longitudinal length of each longitudinal section along which the longitudinal section is to be separated into lateral sections;
placing a sleeve laterally around the longitudinal section at the identified elevation, the sleeve extending an incremental distance on either side of the elevation; and
laterally shearing at least one of the longitudinal sections at the elevation and substantially simultaneously sealing the sleeve against an opposite side of the sleeve as it is sheared.
2. The method of claim 1 wherein the incremental distance is substantially between one and four inches (2.54 and 10.16 cm).
3. The method of claim 2 wherein the incremental distance is more preferably between two and three inches (5.08 and 7.62 cm).
4. The method of claim 1 wherein the sleeve has a thickness of approximately one eighth of an inch (0.32 cm).
5. The method of claim 1 including the step of forming the sleeve from a malleable metal.
6. The method of claim 5 wherein the malleable metal is either stainless steel or copper.
7. The method of claim 1 wherein the step of separating the central spline is achieved by making two cuts along the elongated length and 180 degrees around the circumference of the spline with the two cuts being made substantially at the same time.
8. The method of claim 1 wherein the sealing step is achieved by crimping a sheared end of the sleeve to the opposite side of the sleeve.
9. The method of claim 8 wherein the crimping step and the shearing step occur substantially simultaneously.
10. The method of claim 1 wherein the placing step includes the step of wrapping the sleeve laterally around the longitudinal section at the identified elevation.