ML22277A739
| ML22277A739 | |
| Person / Time | |
|---|---|
| Site: | 07103097 |
| Issue date: | 08/03/2023 |
| From: | Boyle R, Shaw D TN Americas LLC |
| To: | Division of Fuel Management |
| Garcia-Santos N | |
| Shared Package | |
| ML22277A716 | List:
|
| References | |
| A33010, L-2022-DOT-0008 | |
| Download: ML22277A739 (6) | |
Text
Unrestricted Orano Orano NPS APPENDIX 1.4-5 SAFETY ANALYSIS ANALYSIS OF THE AGEING MECHANISMS OF THE FCC3 AND FCC4 REPORT PACKAGE MODELS ()
Prepared by / signature orano FCC3/FCC4
Verified by / signature
Identification: DOS-19-021166-010-NPV Version 1.0 Page 1 / 6
Contents Statusofrevision 2
- 1. Introduction 3
- 2. Descriptionofpackaginguse 3
- 3. Materials 3
- 4. Potential effectsonthepackagecomponents 4
- 5. Conclusion 6
- 6. References 6
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification: DOS-19-021166-010-NPV Version 1.0 Page 2 of 6
Status of revision
Version Date Purpose and record of revisions Prepared by/ Verified by
1.0 See page 1 First issue
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification: DOS-19-021166-010-NPV Version 1.0 Page 3 of 6
- 1. Introduction
The purpose of this chapter is to present the aspect justifying that the package as defined in this safety analysis report meets the requirements in section 613A of the IAEA regulations <1>.
- 2. Description of packaging use
The FCC3 and FCC4 models are intended for the transpor t of fresh fuel as type IP-2 or type A package containing fissile material.
The FCC3 and FCC4 packagings are used as per the requirements of chapter 1.7, particularly with dry loading/unloading of content. The loadi ng and unloading operations are carried out:
With the internal equipment in a vertical position for the assemblies with or without control clusters, With the internal equipment equipped with rod box es in a horizontal position for non-assembled rods.
The maximum power of the contents is W.
The loaded packagings are designed to be transport ed on public highways in a horizontal position.
- 3. Materials
The materials used in the components of the FCC3 and FCC4 packagings are described in chapter 1.4.
The content is described in chapter 1.3. It is constituted of leak-tight zirconi um alloy rods enclosing non-irradiated enriched uranium pellets which are either placed in a metal structure forming the fuel assemblies or take the form of non-assembled rods. The non-assembled rods are collected in rod boxes, whose constituent materials are specified in chapter 1.3-1.
The main package materials (important with regard to containment safety, radiation protection and criticality safety functions, along with the drop and fire protection functions) subjected to the transport conditions are listed in the table below:
Component Material Corrosion protection coating Steels and Yes Lower and upper half-shells ( and ),, (Corrosion Closure flange protection coating +
Steels, paint coating)
Steel Grade LF2 Internal equipment:
Doors and frame, Stainless steels top and bottom plates, -
connection of doors with frame, connection of top and bottom plates with frame and doors, Half-shells bolted connections: ( class )
Special head screws or Yes Nuts of special head screws Neutron-absorbing resin contained in the doors and frame (see table 1.4.1 of chapter 1.4) -
Axial shock absorber Balsa -
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification: DOS-19-021166-010-NPV Version 1.0 Page 4 of 6
Component Material Corrosion protection coating Shock absorber closure plate -
Shock absorber bolted connections with the upper shell -
Rod box:
radial spacers and radial support plate, - stainless axial spacers and axial end support steel -
plate Rod boxes:
radial compensation spacers Aluminium alloy -
Claddings Zirconium alloy M5Framatome and Zircaloy-4 -
- 4. Potential effects on the package components
On the basis of the transport conditions (overland, ma ritime, river), the following effects must be taken into account:
The effect of moisture (external environment),
The effect of temperature on the materials, The effect of irradiation due to the presence of radioactive material, The effect of fatigue caused by the transport method.
4.1. The effects of moisture
The following section details the design and operating principles used to evaluate the effects of moisture.
As the packagings are dry-loaded in buildings protected from adverse weather, the moisture in the packaging corresponds to that of the r oom at the time the contents are loaded/unloaded.
All the outer surfaces of the upper and lower shells are protected by a paint coating or a corrosion protection coating (for the bolted joints of the half-shells for example).
The FCC3 or FCC4 packaging is equipped with a cleanliness gasket for the connection between the half-shells, limiting the risks of water penetrating inside the half-shells.
The metal internal equipments are.
The shock absorbers are formed of a enclosure. The wood is therefore contained in leak-tight enclosures. Before each shipment, the shock absorbers are checked for permissible defects (as defined in chapter 1.4), to detect any deterioration (see chapter 1.7).
As an additional means of prevention:
Before shipment (see chapter 1.7):
Check that the paintwork has not detac hed from the uninterrupted sections of the packaging, Check that there is no water in the bottom of the lower shell.
To each periodic servicing(see chapter 1.8):
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification: DOS-19-021166-010-NPV Version 1.0 Page 5 of 6
Search for paintwork defects and restauration if necessary of the defective zones on the inner and outer shell surfaces if deficient paintwork is detected, Visually and functionally check over the entire stroke of all the connecting bolts, with nuts, for the 2 half-shells Systematically check the good overall condition of the packaging.
The checks carried out before each transpor t and during maintenance operations protect against any corrosion effects caused by mo isture for the FCC3 and FCC4 packagings.
Regarding the content, fissile material is contai ned by the fuel rod claddings and the zirconium alloy welded plugs. The fuel assemblies (compo sed of fuel rods) are intrinsically designed to operate in a wet environment under high pressure and temperature in the reactor core; as a result, moisture is not expected to affect the c ontainment of the fuel rods in ambient conditions during the regulatory transport period not exceeding one year.
On this basis, as far as the presence of moisture is concerned, the design, the use and the servicing of the FCC3 and FCC4 packages are such that their condition cannot be modified in any manner liable to modify the conclusions of the analysis chapters in this safety analysis report.
4.2. The effects of temperature on the materials
As mentioned in §2, after loading, the packaging releases a maximum power of W.
Regarding the fuel assembly claddings and bearing in mind the low power of the contents and the maximum temperature in normal conditions of transport of + °C (see chapter 2.2), no thermal creep effect is expected throughout the transport period.
Regarding the neutron-absorbing resin in the doors and in the frame of the internal fittings, the maximum temperature reached by the package remains well below the limit operating temperature of the resin (°C). In these low temperature conditions, considering the operating limit, no significant ageing effect is expected for the chemical composition of the resin over the packaging service life (a period at least equal to 37 years, which corresponds to the minimum fatigue service life for the FCC3 an d FCC4 packagings as defined in chapter 2.1).
The effects of the maximum temperature in normal conditions of transport (+ °C) on the mechanical behaviour of the aluminium in the rod box compensation spacers and on the degradation of the paintwork on the half-shells ar e negligible. Moreover, as stated in §4.1, checks on the paintwork condition before sh ipment and during packaging maintenance provide protection against any degradation.
Thus, considering the low thermal power of the contents, no significant effect of thermal ageing on the FCC3 and FCC4 packaging components is expec ted over the whole service life of the packaging (at least 37 years).
4.3. The effects of irradiation due to the presence of radioactive material
The claddings of the fuel assemblies are made of zirconium alloy type M5 Framatome or Zircaloy-
- 4. These materials have a very low neutron absorption cross-section in the thermal domain and do not undergo irradiation ageing due to the neutrons.
As the fuel is not irradiated, the radiation level sustained by the package materials is low. On this basis, variation in the properties of t he packaging materials and of the content (see §3) under the effect of irradiation are not signific ant throughout the service life of the FCC3 or FCC4 packaging and throughout the transport period for the content (no more than one year as per regulations).
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification: DOS-19-021166-010-NPV Version 1.0 Page 6 of 6
4.4. The effects of fatigue caused by the transport methods
Fuel assembly cladding stresses in the transport phase are limited by the strength of the packaging structures surrounding them.
Chapter 2.1 shows that the package model withstands the stresses arising from road, maritime and rail transport over a period of at l east 37 years, under repeated tie-down and handling conditions (at a rate of transport operations per year for the FCC3 packaging and transport operations per ye ar for the FCC4 packaging).
Further, during each maintenance operation, t he FCC3 and FCC4 packagings are subjected to the following checks (see chapter 1.8):
systematic check of the good overall condi tion of the packaging and replacement of any non-compliant component, 100% surface inspection of the welds connec ting the handling boxes and the upper shells, the welds on the reinforcing support angles located on each side of the handling boxes and the peripheral welds between the half-shells and the flanges, Check pin wear, Check for deformation and the good condition of the pin and connection stops (retaining rings, lock pin, set screw, lock washer, presence of thread lock),
Check the condition of the ball locking pins and effective locking in the clevises.
Moreover, the good overall condition of the packaging is checked for each transport operation.
On this basis, as far as the effects of fati gue related to the transport methods are concerned, the design, the use and the servicing of the FCC3 and FCC4 packages are such that their condition cannot be modified in any manner liable to modify the conclusions of the analysis chapters in this safety analysis report throughout the packaging se rvice life (at least 37 years).
- 5. Conclusion
The FCC3 and FCC4 packagings are designed for the transport of fresh fuel rod assemblies or non-assembled fresh fuel rods.
Chapters 1.7 and 1.8 describe the packaging maintenance and use conditions for transport operations.
The analyses conducted in this chapter demonstrate that, with consideration for the guidelines, the safety functions of the FCC3 and FCC4 packagings ar e not deteriorated due to ageing over a minimum period of 37 years (defined in the fatigue analysis for the conveyances).
Accordingly, the FCC3 and FCC4 package models are designed to meet IAEA regulations <1>
particularly §613A, which states: The design of the package shall take into account ageing mechanisms.
- 6. References
<1> Regulations for the safe transport of radioacti ve material - Specific safety requirements No.
SSR IAEA - see edition applicable to Chapter 1.2.
Non-proprietary version