ML20086M251
| ML20086M251 | |
| Person / Time | |
|---|---|
| Site: | 07109377 |
| Issue date: | 03/24/2020 |
| From: | Pierre Saverot Storage and Transportation Licensing Branch, Orano USA, TN Americas LLC |
| To: | Christopher Regan Division of Fuel Management |
| Saverot P | |
| Shared Package | |
| ML20086M199 | List: |
| References | |
| EPID L-2019-LRM-0029 | |
| Download: ML20086M251 (17) | |
Text
TN-32B High Burnup (HBU)
Demonstration Cask NRC Docket 71-9377 24 March 2020
2 Agenda
Introductions
Meeting Objectives Plan for Collection of Thermal Data in Transportation Configuration TN-32B HBU Demonstration Cask Design - Transport Updated Planned Schedule for License Application Questions TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
3 Meeting Objectives Review of TN-32B HBU Demonstration Cask and Payload Discuss Collection of Additional Thermal Data Discuss TN-32B HBU Demonstration Cask Transport Configuration Discuss Leak Tightness of Thermocouple Lance Assemblies for Transport Discuss the Revised Schedule for Submittal of Application TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
4 TN-32B HBU Demonstration Cask Design Metallic, Welded Constructed Storage Cask Maximum Gross Weight: 272,002 lbm Overall Dimensions: 144 inch x 262 inch length 1.5-inch thick inner containment shell and bottom plate 4.5-inch thick closure lid containment plate w/ 6-inch thick welded shield plate 8-inch thick outer shield forging surround containment shell 8.75-inch thick shield plate covering bottom containment plate 4.5-inch thick neutron shield surrounding outer shield forging Impact limiters installed on each end Same design as utilized on licensed TN-40 & TN-68 casks Utilizes same redwood & balsa wood for impact absorption Modified Closure Lid Thermocouple lance assemblies installed through lid TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
5 High Burnup (HBU) Payload Selected (32) PWR HBU fuel assemblies Spent nuclear fuel assemblies with burnup greater than 45 GWd/MTU Four different cladding types: (18) M5', (12) ZIRLO', (1) Zr-4, and (1) Low-Sn Zr-4 Stored on North Anna Power Stations ISFSI for 10-years Assembly temperatures monitored by seven (7) thermocouple lance assemblies installed through the closure lid Six (6) Poison Rod Assemblies (PRAs) installed for criticality control Payload loaded in cask and placed on ISFSI pad in November 2017 TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
6 Collecting Additional Thermal Data Previously planned approach for transport:
Cease collecting thermal data at the end of the storage period at North Anna Abandon thermocouples in preparation for transport
- Sever thermocouple cables/OP tubing
- Seal penetrations with a solid 1-inch thick welded alloy steel plate
- Install 2-inch thick puncture resistant alloy steel plate
- Thermocouple lance assemblies not part of containment boundary Following discussions with stakeholders (DOE, EPRI, National Labs),
desire to obtain additional thermal data in the horizontal orientation after transport Results in the need to maintain thermocouples intact for transport TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
7 Maintaining Thermocouples in Transport Required changes to planned approach for transport to maintaining thermocouples intact:
Thermocouple cables/OP tubing are not severed Provide thru-hole in 1-inch thick welded alloy steel plate for cable/connector pass-thru Raise puncture resistant plate off the closure lid surface for cable/connector clearance Revise the thickness of the puncture resistant plate to 1.75 inch to allow for machining Insert spacer support steel bars around the thermocouple lance penetrations Thermocouple lance assemblies become part of containment boundary Provide defense in depth to provide containment of payload:
- Primary
- Secondary
- Tertiary TN-32B HBU Demonstration Cask NRC Mtg, 3-XX-2020
8 TN-32B HBU Demonstration Cask, Containment Boundary Propose to Utilize Lance Assemblys:
Primary and Secondary Confinement Boundaries in Storage Primary and Secondary Containment Boundaries in Transport Primary Containment Boundary of Lance Assembly Closure is constructed of Type 304L stainless steel 160.2-inch long lance oversheath tube, reinforcing oversheath tube, lower closure plug and tip plug are constructed of annealed alloy Type UNS N06600 Penetration is sealed by a Helicoflex silver jacketed metallic O-ring seal All welds performed using Gas Tungsten Arc Welded (GTAW) process Secondary Containment Boundary of Lance Assembly Closure, same as primary Upper closure plug is constructed of Type 304L stainless steel Overpressure tubing, which is constructed of annealed nickel-based alloy (Type UNS N06600), will be capped for transportation Upper closure plug to closure weld performed using GTAW process Upper closure plug-to-metal sheathed thermocouples and overpressure tubing are silver brazed TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
9 TN-32B HBU Demonstration Cask, Containment Boundary (cont)
Tertiary Containment Boundary - Modified Puncture Resistant Alloy Steel Plate A 1.38-inch gap is added between plate and modified closure lid for storing the thermocouple lance cables Closure lid bolts are covered completely Spacer support bars are welded to puncture resistant plate or closure lid:
- Spans the lance penetration cover plate weld joint
- Provides additional protection of lance assembly for postulated HAC puncture drop impact
- Directs postulated HAC puncture bar impact load into closure lid plate Double elastomer O-ring seals added to seal against cask body flange to provide an additional level of containment TN-32B HBU Demonstration Cask NRC Mtg, 3-XX-2020
10 Containment boundaries of thermocouple lance assemblies
© Photo credit to be completed TN-32B HBU Demonstration Cask, Transport Configuration (contd)
TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
11 Thermocouple Lance Penetration Cover Plate with thru-hole for Connector/Cable
© Photo credit to be completed TN-32B HBU Demonstration Cask Design, Transport Configuration (contd)
TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
12 TN-32B HBU Demonstration Cask Design, Transport Configuration (contd)
TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
13 Leak Tightness of Lance Assemblies For Transport Lance Assemblies and O-ring Seals Leakage Rate Tested per ANSI N14.5:
Verification test included containment weld of penetration forging Verified to be leaktight during fabrication and assembly for storage Metallic O-ring seals continuously monitored during storage period
§71.73(c)(1) 9-meter (30-foot) Free Side Drop Effect on Assembly Postulated lateral movement of assembly due to impact Metallic O-ring seal could possibly be affected Plan to Test of Prototypic Lance Assembly and Metallic O-ring Seal Interface Configuration to replicate installed lance assemblies in cask lid Perform leakage rate test pre-lateral movement of metallic O-ring seal Exert lateral force on assembly to translate assembly/seal maximum displacement Perform leakage rate test post-lateral movement of metallic O-ring seal Effect of temperature to be considered in test Record lateral force to translate lance assembly for comparison to side drop impact Test results to demonstrate leak tightness of lance assembly/seal is maintained during transport TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
14 Leak Tightness of Lance Assemblies For Transport (cont)
Primary Containment Provided by Lance Assemblies:
Protected by impact limiter for postulated free drop impacts and thermal event per
§71.73(c)(1) and §71.73(c)(4), respectively Protected by 1.75-inch thick puncture resistant plate and support bars for postulated puncture bar impact per §71.73(c)(3)
Plan to verify sealing maintained during any lateral translation of thermocouple lance assembly Verified lance oversheath complies with ASME III NB Level D stress limits for 0.416 inch lateral displacement of funnel/fuel assembly Additional assurance provided by sealing of puncture resistant plate to cask body flange Defense in depth provided by secondary and tertiary containment boundaries TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
15 Planned Schedule for License Application Calculations and SAR chapters to be completed within 6 months Submittal of SAR to NRC in early 4th quarter 2020 Receipt of NRC Requests for Additional Information (RAIs) in 2nd quarter 2021 Receipt of NRC Certificate of Compliance in 4th quarter 2021 License application submittal to support planned transport in 2027 Planned pre-transport activities:
Fabrication of impact limiters, transportation skid, and auxiliary equipment Transportation planning from NAPS to a site to be identified later TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020
16 Questions?
TN-32B HBU Demonstration Cask NRC Mtg, 3-24-2020