ML23317A245
| ML23317A245 | |
| Person / Time | |
|---|---|
| Site: | 07109316 |
| Issue date: | 11/21/2023 |
| From: | Storage and Transportation Licensing Branch |
| To: | Alpha-Omega Services |
| Shared Package | |
| ML23317A244 | List: |
| References | |
| EPID L-2023-LLA-0099 | |
| Download: ML23317A245 (3) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION REPORT Model Nos. AOS-025A, AOS-050A, AOS-100A, AOS-100B, and AOS-100A-S Packages Certificate of Compliance No. 9316 Revision No. 12
SUMMARY
By application dated July 19, 2023, Alpha-Omega Services, Inc. (AOS, the applicant) submitted an amendment request to update the containment bolting analysis and evaluate a range of torque values for the cask lid attachment bolts for all the Model Nos. AOS-025A, AOS-050A, AOS-100A, AOS-100B, and AOS-100A-S packages.
The applicant submitted revised licensing drawings pertaining to each Model of the AOS series of packages, a list of changes to the application and Revision J3 of the safety analysis report (SAR) Radioactive Material Transport Packaging System Safety Analysis Report for Model AOS-025, AOS-050, and AOS-100 Transport Packages AOS-FM9054, dated July 19, 2023.
U.S. Nuclear Regulatory Commission staff reviewed the application using the guidance in NUREG-2216. Based on the statements and representation in the application, as supplemented, and the conditions listed below, the staff concludes that the new torque values do not affect the ability of the package to meet the requirements of Title 10 of the Code of Federal Regulations (10 CFR) Part 71.
EVALUATION The family of AOS transportation packages consists of the AOS-025A, AOS-050A, AOS-100A, AOS-100B, and AOS-100A-S. The A designation refers to a tungsten shield, and the B designation refers to a carbon steel shield. The S designation on the AOS-100A-S means that the cask is double ended and there is a lid on each end of the cask. All the packages have the same geometric shape, with the AOS-025A and AOS-050A having all dimensions scaled down to 25 percent and 50 percent (respectively) of the dimensions of the AOS-100 package.
The licensing drawings were updated to the following revisions:
Model Assembly Rev Impact Rev Packaging Rev Limiter AOS- 166D8142 K 105E9722 J 166D8143 K 025A AOS- 105E9718 K 166D8138 I 166D8137 K 050A AOS- 105E9711 L 105E9713 J 105E9712 N 100A G001 AOS- 105E9711 L 105E9713 J 105E9712 N 100B G002 AOS- 105E9711 L 105E9713 J 105E9719 N 100A-S
2 The minimum and maximum torque values for the Cask Lid Attachment Bolts are as follows:
Model Lid Bolt (ft-lb), lubricated Impact limiter connector (ft-lb), lubricated AOS-025A 29 - 35 10 AOS-050A 62.5 - 68 3 AOS-100A 400 - 500 70 AOS-100B 400 - 500 70 AOS-100A-S 400 - 500 70 Structural Evaluation The purpose of this update is to (i) change cask lid attachment bolt preload torque values for the above models, from a single value to a range bounded by a minimum & a maximum value, (ii) correct some minor errors, (iii) clarify that the cask lid attachment bolts must be lubricated prior to use, (iv) replace Appendices 4.5.2 and 4.5.3 with new Appendix 4.5.2, Cask Lid Attachment Bolt Evaluation, and (v) clarify chapter 4 and 8 reference lists.
Staff review of the SAR drawings finds that the updated torque ranges are included in the drawings for AOS-025A, AOS-050A, AOS-100A, AOS-100B, and AOS-100A-S. The staff noted that the upper and lower bound torque values are used in the new Appendix 4.5.2 for analyzing the bolts under different load conditions consistent with the guidance in NURGE-6007.
The cask lid attachment bolt evaluation is performed for all AOS-025A, AOS-050A and AOS-100 models in Appendix 4.5.2. The equivalent-static acceleration and dynamic load factor are determined for the impact load case. Other load cases are also derived to establish the applicable load combinations per NUREG/CR-6007 to perform the bolt stress analysis. Bolt thread engagement length check, lid flange separation analysis, and bolt fatigue analysis are also performed in the attachment.
The calculation results show that the bolt stresses are less than the stress limits specified in the NUREG/CR-6007, which are based on American Society of Mechanical Engineers Boiler and Pressure Vessel code,Section III, Subsection NB. The staff finds this acceptable as the acceptance criteria is consistent with the design code.
The staff notes that these drawings specified different maximum values for the lid weight of each model. The applicant clarified that these lid weighs are from a legacy item left from the design phase, around 2007-2008. They continue to be used conservatively for cask design. The applicant agreed to update to the actual weight of the lid in the next revision of drawings.
Revisions to chapter 7 Package Operations were made to include the information specified by the revised certification drawings. The applicant also specified that the cask lid attachment bolts must be lubricated with a lubricant such as Neolube No. 2 or any other lubricant pre-approved by AOS. The applicant also specified that, in the case of wet loading, the lubricant must be applied after the cask has been removed from the pool and dried.
Based on the review of the attachment and the change item comparison in the application, the staff determined that the bolt analysis and other minor updates are acceptable and concluded
3 that the package maintains adequate structural integrity to meet the structural requirements of 10 CFR 71.43.
Changes to Certificate of Compliance The following changes are included in Revision No. 12 to Certificate of Compliance No. 9316:
Item No. 3.b was revised to reference the updated safety analysis report.
Condition No. 5(a)(3) was revised to reference the updated licensing drawings.
Condition No. 12 was revised to update the table with the new torque values.
Condition No. 15 was revised to authorize the use of the previous revision of the certificate for approximately one year.
The expiration date of the certificate was not changed.
The References section of the certificate was updated to identify the amendment request dated July 19, 2023.
CONCLUSION Based on the statements and representations contained in the application, as supplemented, and the conditions listed above, the staff concludes that the design of the Model Nos. AOS-25A, AOS-050A, AOS-100A, AOS-100B, and AOS-100A-S packages has been adequately described and evaluated.
The staff concludes that the changes indicated do not affect the ability of the package to meet the requirements of 10 CFR Part 71.
Issued with Certificate of Compliance No. 9316, Revision No. 12.