ML23256A347
| ML23256A347 | |
| Person / Time | |
|---|---|
| Site: | 07103035 |
| Issue date: | 05/30/2023 |
| From: | Garcia-Santos N Storage and Transportation Licensing Branch |
| To: | Boyle R US Dept of Transportation (DOT), Office of Hazardous Materials Safety |
| Garcia-Santos N | |
| Shared Package | |
| ML23256A340 | List: |
| References | |
| CAC 001794, EPID L-2023-DOT-0006 | |
| Download: ML23256A347 (2) | |
Text
Request for Additional Information Docket No. 71-3035 Model No. J RC-80Y-20T Japanese Certificate of Competent Authority J/2045 /B(U)F
The questions below describe information needed by the staff for it to complete its review of the application and to determine whether the applicant has demonstrated compliance with regulatory requirements.
Structural Review
RAI St-1 Provide a complete evaluation of fatigue for the reusable package components for the 7 0-year period of use that considers the combined effects of all applicable types of accumulated stress cycles in components during normal service conditions, including the following cycle types (as described in this question):
- a. Lifting cycles
- b. Pressurization cycles
- c. Thermal stress cycles
- d. Vibration cycles
The staff needs a complete fatigue evaluation that considers the combined effects of all applicable types of stress cycles during normal service, including consideration of the cycle types listed above. Also, the appropriate number of cycles need to be considered in fatigue evaluation depending upon the type of cycle being evaluated or considered. If certain types of stress cycles are not applicable or negligible for certain components, explain why these are not applicable or are negligible.
If such a complete fatigue evaluation cannot be performed, or if the fatigue evaluation cannot show adequate protection against fatigue failure considering the combined effects of all applicable types of accumulated stress cycles in components, provide the following information:
a.1 a description about how periodic maintenance inspections will be used to identify and address fatigue cracks in components of the package
b.1 A description of the corrective actions that will be taken for any detected fatigue cracks, such as analytical flaw evaluation with follow-up inspections, repair/replacement of components with cracks, etc.
The following provide additional descriptions about accumulated stress cycles as provided in the application:
- 1. Lifting cycles - The staff recognizes that these cycles are already evaluated in sections (II)-A.4.4.2.1.3, (II)-A.4.4.2.2.4 and table (II)-F.2 of the SAR. However, the staff noted that the lifting cycles are evaluated without considering the other types of stress cycles that may also be accumulated by the lifting devices. To perform an adequate analytical evaluation that demonstrates sufficient safety margin against fatigue failure of these components, the combined effects of accumulated lifting cycles along with other applicable types of accumulated stress cycles in
Page 1 of 2 Request for Additional Information Docket No. 71-3035 Model No. J RC-80Y-20T Japanese Certificate of Competent Authority J/2045 /B(U)F
these components (including consideration of cycle types listed herein) on the potential for fatigue of lifting devices should be considered.
- 2. Pressurization and thermal stress cycles - The staff recognize that pressure and thermal cycles are already evaluated in sections (II) -
A.5.1.3.3 and table II-F.2. However, the staff noted that the containment device pressurization & thermal cycles are only evaluated for the most critical component, the lid bolt considering 300 cycles (frequency of 4 times per year for handling sealing device) over 70 years. Also, the staff noted that thermal stress cycles may occur in components due to cyclical fluctuation of spatial temperature gradients within components, which could significantly exceed 300 cycles over 7 0-year service life. In addition, the staff noted that this evaluation does not address the potential for fatigue of package components due to the combined effects of pressurization and thermal stress cycles with other types of stress cycles that may also be accumulated by the containment device components. To perform an adequate analytical evaluation that demonstrates sufficient safety margin against fatigue failure of these components, the combined effects of accumulated pressurization & thermal cycles along with other applicable types of accumulated stress cycles in these components (including consideration of cycle types listed herein) on the potential for fatigue of containment device components should be considered.
- 3. Vibration cycles - The staff noted that section (II)-A.4.7 provide an evaluation that demonstrates that package resonance is a not a concern considering package vibration caused by vehicle transport. However, the staff noted that this evaluation does not address the potential for fatigue of the package and tie-down components due to the combined effects of the accumulation of many vibration cycles resulting from the allowed transports of the package over 70-year service life (with each transport experiencing long distance travel over potentially rough roads), along with the accumulation of other applicable types of stress cycles, including consideration of the cycle types listed herein.
To determine that fatigue as not an aging concern, as indicated in section ( II)-F of the application, the staff needs a complete fatigue evaluation that considers the combined effects of all applicable types of stress cycles during normal service, including consideration of the cycle types listed above. Also, the appropriate number of cycles need to be considered in fatigue evaluation depending upon the type of cycle being evaluated or considered.
This information is requested to determine compliance with the requirements in paragraphs 503(e), 613, 613A, and 809(f) of the IAEA SSR-6, 2018 Edition.
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