ML22061A180

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Orano NPS Safety Analysis Report, Document Number DOS-19-022728-005 Version 2.0
ML22061A180
Person / Time
Site: 07103092, 07100653
Issue date: 07/12/2021
From:
Orano TN Americas
To:
Office of Nuclear Material Safety and Safeguards
N DEVASER NRC/NMSS/DFM/STLB 3014155196
References
E-58966 DOS-19-022728-005 E, Ver 2.0
Download: ML22061A180 (14)


Text

Orano TN SAFETY ANALYSIS CHAPTER 00-1 REPORT PERFORMANCE CHARACTERISTICS OF THE PACKAGE Prepared by This document is a translation of the Formulaire : PM04-4-MO-6E rév. 02 DOS-19-022728-005 Vers 2.0 and was verified by , Principal TNF-XI Engineer.

Verified by Identification : DOS-19-022728-005 E Vers. 2.0 Page 1 / 14 Table of contents

1. INTRODUCTION 3
2. DESCRIPTIONS AND DEFINITIONS 3
3. MECHANICAL PERFORMANCE 5
4. THERMAL PERFORMANCE 9
5. DOSE EQUIVALENT RATE PERFORMANCE 10
6. CRITICALITY-SAFETY PERFORMANCE 11
7. CONDITIONS OF USE 13
8. PERIODIC MAINTENANCE PROGRAMME 13
9. QUALITY ASSURANCE PROGRAMME 14
10. REFERENCES 14

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 2 of 14 Revision status Version Date Modifications Prepared by / Verified by

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1.0 17/04/2020 First issue

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2.0 See 1st page Correcting typos

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 3 of 14

1. INTRODUCTION The purpose of this chapter is to describe the performance characteristics of the TNF-XI package model, which is designed for transportation by road, rail or sea, and loaded with radioactive material as a type A or type IP-2 package containing fissile materials, in accordance with the regulations <1>.
2. DESCRIPTIONS AND DEFINITIONS 2.1. Description of the package The TNF-XI packaging is intended for the transport of uranium oxides (UO2, UO3 and U3O8),

in the form of powder, pellets or scraps, or uranium complexes mixed with residues, by road, rail and sea.

The packaging is designed and dimensioned to be compatible with the installations and their handling facilities.

In a parallelepiped general shape, the TNF-XI package model is illustrated in the following figure.

TNF-XI packaging diagram The overall general dimensions of the package are:

x Height = 1.040 m x Body cross-section = 1.1 x 1.1 m

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 4 of 14 2.2. Description of the packaging The packaging comprises the following principal sub-assemblies:

x a phenolic foam body of different densities provides damping and thermal insulation, having four internal partitioned stainless steel cylindrical cavities. The cavities are kept separate by means of a total of eight reinforcing tubes.

x The body is enclosed in stainless steel. Around each cavity, a thickness of resin ensures neutron protection and isolation of the packages.

x a primary stainless steel lid fitted to each cavity. The seal between the cavity and the primary lid is provided by a gasket. The closure of these lids on the flange is ensured by a bayonet system.

x one plug per cavity, providing mechanical damping and thermal protection, and consisting of phenolic foam, aluminium reinforcement and a boron steel disc welded to the stainless steel shell of the plug. The plug is held above the primary lid by a secondary lid secured by a stainless steel bayonet system.

x a cleanness cover, covering the entire top side of the packaging, preventing access to the plugs, clipped to the outer shell of the packaging body.

2.3. Description of the content The TNF-XI packaging is intended for the transport of the following contents:

 UO2, UO3 or U3O8 uranium oxide in powder, pellet or scraps form, which may or may not be mixed with residues;

 UO2, UO3 or U3O8 uranium oxide in powder, pellet or scraps form with unlimited gadolinium and erbium present.

 uranium complexes (uranium in oxide form, uranyl nitrate, sodium diuranate or ammonium diuranate), in solid form, mixed with residues from incineration or residues of earth, sand and dissolution.

The residues are chemically stable and contain no liquid.

The maximum permissible mass of uranium, in all possible forms listed above, distributed in the three pails of the packaging, is limited.

The authorised content limits the safety-critical parameters, as used in the Safety Analysis Report, in particular:

 isotopic vector;

 physical state (in pellet, powder or fragment form) and chemical form;

 maximum 235U enrichment level;

 maximum admissible mass of heavy metal;

 maximum density.

The material may be placed in bags made of materials more hydrogenated than water. The packaged (or unpackaged) material is placed in stainless steel pails (three for each of the four cavities) complying with the following criteria:

 vertical installation;

 stainless steel lid with closing ring;

 a steel (possibly boron steel) ring.

Each cavity must always contain the three pails with their steel ring.

The mass of plastic more hydrogenated than water is limited per cavity.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 5 of 14 A spacer system enables radial centring and axial spacing of the pails in each cavity.

2.4. Containment vessel The containment vessel for the packaging consists of:

x the four internal cylindrical stainless steel enclosures; x the four flat stainless steel bottoms welded to the cylindrical internal enclosures; x the four primary lids and their gasket.

2.5. Isolation system The isolation system comprises:

x the fissile content (powder, pellet or fragment),

x the internal fittings of the cavity (excluding the spacer system) described in paragraph 2.3, x the main sub-assemblies (excluding the protective lid) described in paragraph 2.2.

2.6. Mass balance The following table gives the maximum masses of the content and the TNF-XI package in transport configuration.

Item Mass (kg)

Maximum mass of content 300 Maximum mass of the package authorised for 1050 transport This is the mass generically used in the safety studies.

3. MECHANICAL PERFORMANCE 3.1. Routine conditions of transport The packaging dimensions make it suited to transportation by road, rail or sea.

Resistance to accelerations The package is designed to withstand accelerations representative of routine conditions of transport. These accelerations are not likely to cause damage to the package.

Resistance to pressure The containment vessel must retain the radioactive contents in the event of a drop in ambient pressure of up to 60 kPa. A pressure differential of 0.45 bar is then used to evaluate the mechanical strength of the components of the package containment system.

The mechanical strength of the containment vessel at a pressure of 0.45 bar is verified by analytical calculations, comparing the stresses in the steel with its yield strength.

Conformity with requirements is checked.

Stowing and handling The TNF-XI package model is transported in an upright position in a 20-foot ISO container.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 6 of 14 The packages are blocked axially and radially by means of wooden blocks, interposed between each package.

In the case of incomplete loading (insufficient number of TNF-XI packagings to fill the lower level of the 20-foot ISO container), the packages are stowed using straps.

For handling, the underside of the packaging is equipped with steel forklift passages.

3.2. Normal conditions of transport Safety analyses study the consequences of regulatory tests simulating normal conditions of transport.

The studies show that:

x If the packaging is sprayed with water, the outer surface is moistened but the characteristics of the packaging are unchanged.

x The resistance of the packaging to the stacking test is checked by analytical calculation.

The packaging can withstand the stacking test without damage.

x The penetration test does not significantly alter the geometry of the packaging in view of the very minor deformations observed.

x The drop test from a height of 1.20 m does not significantly change the geometry of the packaging, considering the very minor deformations observed.

Damage The seal of the packaging is maintained subsequent to drops of 1.20 m.

The containment vessel is preserved and the deformations of the outer enclosure of the packaging are minor.

The effect of packaging deformations on increasing dose equivalent rates is discussed in paragraph 5.3.

3.3. Accident conditions of transport This paragraph details the consequences of regulatory tests simulating the accident conditions of transport applicable to the TNF-XI package model.

In particular, in the remainder of the paragraph, all drop analyses are carried out with respect to a total package mass of 1,050 kg.

In accordance with the regulations for packages containing fissile materials, the criticality-safety analyses take into account the aggregate results of the drop tests under normal and accident conditions of transport.

Resistance to immersion test Due to the geometry of the seal, the watertightness of the TNF-XI packaging in the event of an external overpressure (external gauge pressure of at least 150 kPa) is not required. At the end of the immersion test, water will penetrate all the empty spaces in the packaging.

The modelling chosen for the criticality-safety studies takes into account unlimited penetration of water into the cavity.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 7 of 14 Definition principle of drop test prototypes The drop tests were carried out with several full-scale prototypes of the TNF-XI package.

Rules of similitude are applied to guarantee that the mechanical stresses on the components of the prototype are, as a minimum, equivalent to those on the same components of the packaging model. The mechanical behaviour during a drop test will therefore be considered identical for both the prototype and the package.

Set of drop tests studied All drop configurations defined by the accident conditions of the IAEA rules, which may call into question the seal of the containment vessel, the integrity of the radiological and thermal protection, and the isolation system of the package model, are studied.

The demonstration of the resistance of the package to drop tests simulating normal and accident conditions of transport is based on drop tests carried out on different full-scale prototypes of the TNF-XI package.

Initial prototypes were used in preliminary drop tests to define the most penalising drop sequences.

In order to qualify the mechanical behaviour of the package, the drop sequences defined above were tested on other prototypes.

The drop configurations performed during this test programme are detailed in the tables below:

Prototype 1 Description of test Orientation Drop No.

Point of impact:

Penetration test on a 6 kg - side panel 1 bar - top lid 2

- bayonet 3 Point of impact:

- edge of top side 4 Drop from 1.20 m

- corner of top side 5 Point of impact:

- side panel 6 1 m drop onto a bar

- bottom of the packaging 7

- top lid 8 Point of impact:

Drop from 9 m - edge of top side 9

- corner of top side 10 Point of impact:

1 m drop onto a bar - bayonet 11

- top lid 12

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 8 of 14 Prototype 2 Description of test Orientation Drop No.

Point of impact:

Penetration test on a 6 kg 1

- top side bar 2

- bottom of the packaging Point of impact:

3

- side panel Drop from 1.20 m 4

- top side 5

- bottom of the packaging Point of impact:

- bottom of the packaging 6 1 m drop onto a bar

- side panel 7

- branch of the metal cross 8 Point of impact:

- side panel 10 Drop from 9 m

- bottom of packaging 11

- top side 12 Point of impact:

1 m drop onto a bar

- side panel 13 Prototype 3 Description of test Orientation Drop No.

Point of impact:

Penetration test on a 6 kg - safety plate support pin 1 bar - bottom of packaging under the centre of a 2 cavity Point of impact:

Drop from 1.20 m 3

- side panel with 0° angle Point of impact:

1 m drop onto a bar - centre of the bottom of the packaging with 4

an angle of 25° near the middle lifting fork Point of impact:

Drop from 9 m 5

- side panel with 0° angle Point of impact:

1 m drop onto a bar 6

- side panel with 25° angle Prototype 4 Description of test Orientation Drop No.

Point of impact:

- side panel of the packaging facing the 1 Penetration test on a 6 kg centre of a cavity bar - lid of the packaging in the centre of one of 2 the 4 sections of the metal cross

- between two teeth of the lid bayonet system 3 Point of impact:

Drop from 1.20 m - top corner of the packaging with an angle of 4 60°

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 9 of 14 Prototype 4 Description of test Orientation Drop No.

Point of impact:

1 m drop onto a bar -centre of a side panel of the packaging with 5 an angle of 0° Point of impact:

Drop from 9 m - top corner of the packaging with an angle of 6 60° Point of impact:

1 m drop onto a bar 7

- between two teeth of the lid bayonet system Prototype 5 Description of test Orientation Drop No.

Point of impact:

Drop from 1.20 m - top corner of the packaging with an angle of 1 60° Point of impact:

Drop from 9 m - top corner of the packaging with an angle of 2 60° Point of impact:

1 m drop onto a bar 3

- between two teeth of the lid bayonet system To take into account the evolution of the characteristics of the materials constituting the packaging with respect to temperature and the effects of ageing, a complementary calculation of the mechanical behaviour of the package as a function of temperature ([-40°C; TNCTmax]) was carried out.

The study is based on the most penalising drop configuration, namely the 10.2 m oblique drop with impact on the top corner carried out with the P4 prototype.

Results The drop tests performed on the prototypes of the TNF-XI packaging along with the additional calculations demonstrated that the TNF-XI packaging is resistant to the regulatory drop sequences defined by the IAEA Regulation <1>.

The absence of material dispersal outside the packaging is checked, even after a succession of falls much more severe than the regulatory sequence.

The deformations of the packaging observed during the regulatory drop tests are taken into account along with the additional calculations in the thermal safety and criticality demonstrations.

4. THERMAL PERFORMANCE Method of analysis under routine conditions of transport, under normal conditions of transport and accident conditions of transport The study of the behaviour of the package under normal and accident conditions of transport is based on tests carried out in an oven with prototypes that have undergone the drop tests detailed in paragraph 3 and on additional numerical calculations using the I-DEAS software.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 10 of 14 The numerical models used were readjusted in advance on the basis of the measurements taken during the tests by adapting the thermal properties of the numerical model of certain materials in relation to the measurements made during the tests.

On the basis of the previously adjusted model, a numerical calculation is carried out to determine the maximum temperatures reached under NCT (normal conditions of transport), then the behaviour of the package exposed to a temperature of 800°C for 30 minutes, followed by a cooling period in an environment at 38°C under regulatory solar irradiation.

After the thermal tests carried out on prototypes, no powder was found outside the cavities.

Degradation was observed on some materials. These degradations are taken into account in the criticality-safety analyses of the packaging.

The temperature reached by the gaskets and the plastic materials of the internal fittings is lower than their maximum operational temperature, which guarantees the leaktightness of the containment vessel subsequent to accident conditions of transport.

The maximum temperatures reached by the materials are compatible with the criticality hypotheses employed.

5. DOSE EQUIVALENT RATE PERFORMANCE The dose equivalent rate criteria used in the safety analysis report, encapsulating those defined in regulation <1> for a Type A package and an Industrial Type 2 package (IP-2), are as follows:

x the external dose rate at 3 m from the unprotected material does not exceed 10 mSv/h; x routine conditions of transport (RCT): 2 mSv/h in contact with the package; x normal conditions of transport (NCT): no increase of more than 20% in the maximum radiation intensity in contact with the package after representative NCT tests; x the external dose rate at 2 m from the package does not exceed 0.1 mSv/h.

Calculation method Source calculations are carried out using the ORIGEN-ARP 5.1 module of the SCALE 6 system.

Depending on the contents transported, the dose equivalent rates are then calculated with MERCURY V, SN1D or TRIPOLI 4.7 codes.

Content parameters important to the study The radioactive content consists of irradiated and non-irradiated UO2 uranium oxide in powder form.

Packaging parameters important to the study Protection against radiation is provided by the type and thickness of the materials used in the packaging.

The radial shielding is provided by:

x stainless steel shells; x resin layer around each cavity; x stainless steel (possibly boron steel) rings, located inside the pails.

The axial shielding is provided by:

x stainless steel plates;

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 11 of 14 x boron alloy stainless steel plates.

Hypotheses important to the study The following conservative hypotheses are applied to the study:

x the primary lid is not modelled, x the geometry of the pails and shells is simplified. The radioactive sources present in the pails of the same cavity are represented by one and the same content.

5.1. External dose rate 3 m from non-protected material Results of the study The external radiation intensity at 3 m from the unprotected radioactive material does not exceed 10 mSv/h.

5.2. Under routine conditions of transport Results of the study Compliance with the regulatory criteria for the dose equivalent rate under routine conditions of transport is guaranteed for the transported contents.

5.3. Under normal conditions of transport Analysis under normal conditions of transport takes into account damage to the packaging and displacement of the contents in the cavity.

Results:

It is proven that the maximum radiation intensity in contact with the package does not increase by more than 20% following the regulatory tests under normal conditions of transport.

5.4. External dose rate at 2 m from the package Compliance with the regulatory criteria for the dose equivalent rate at 2 m from the package is guaranteed for the contents transported.

6. CRITICALITY-SAFETY PERFORMANCE According to the regulations, nuclear criticality safety must be assured for:

x the isolated package under routine conditions (i.e.: as presented for transportation);

x the isolated package under normal conditions of transport (i.e.: after tests under normal conditions of transport);

x the isolated package under accident conditions of transport (i.e.: resulting from all tests under both normal and accident conditions of transport);

x an array of 5 N packages (where N is the number used to define the regulatory Criticality Safety Index (CSI) coefficient value) under normal conditions of transport; x an array of 2 N packages under accident conditions of transport.

The applicable criticality safety criteria are as follows:

x keff + 3 0.950 for an isolated package, all uncertainties included; x keff + 3 0.980 for a package in an array, all uncertainties included.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 12 of 14 Only the configuration of the package in the state resulting from normal conditions followed by accident drop and fire conditions needs to be considered, so as to cover regulatory requirements and to limit calculation cases.

Since the reactivity obtained in the case of a package array is more penalising than the reactivity obtained in the case of an isolated package, only the case of the package array is considered.

Conservatively, the criticality safety criterion chosen is keff + 3 0.950.

Computer codes The study is carried out using the APOLLO2-MORET4 calculation scheme (standard path of the CRISTAL V1.0 criticality form), based on the use of the CEA93 V6 library for fissile and structural media.

The CEA93 V6 library is a library of 99 and 172 neutron energy group efficient and effective cross-sections. It was developed from the European JEF2.2 evaluation.

The calculation is split into 2 parts:

x the study of the fissile medium and the structural media using APOLLO2 code Version 2.5 Patch 5,

x the calculation of keff for the packaging, via the MORET 4.B.4 Monte-Carlo code.

A qualification study of the calculation schemes used in the criticality safety demonstrations of the TNF-XI package model was carried out.

6.1. Package array Content parameters important to the study In this study, the contents are considered ruined, i.e.: only the uranium oxide is modelled in the most conservative geometric configuration.

The material is considered heterogeneous, to increase the package reactivity.

The enrichment, the mass of heavy metal and the density are the main characteristics of the fuel relevant to this study.

Hypotheses important to the study x The total reflection conditions are applied to all external sides of a single package or cavity, depending on the contents.

x For contents composed of uranium complexes mixed with residues, conservative hypotheses on the reflective materials of the contents and on the chemical form of the fissile material are employed.

x Water fills all the free space in the cavity and the pails.

x The presence of materials more hydrogenated than water is authorised (limit defined according to the contents).

x Where applicable, the pails and rings of boron steel of the pails are modelled by a single pail and a single ring respectively.

x The packaging is considered damaged:

 the damaged part of the phenolic foam is replaced by air or water, whichever is the more penalising;

 the damaged part of the resin is replaced by air or water, whichever is the more penalising;

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 13 of 14

 crushing of the corner of the packaging and puncturing of the foam following regulatory drops are modelled.

Calculation method The fissile material is modelled in the form of a heterogeneous medium (array of spherules).

This hypothesis is conservative for low 235U contents. The fissile medium is moderated either by water or by CH2.

Results of the study The maximum reactivity obtained for an infinite array of packages and considering an unlimited quantity of water is lower than the criticality safety criterion adopted, all uncertainties included, for all the contents transported in the TNF-XI packaging.

The criticality safety index (CSI) = 0.

7. CONDITIONS OF USE The packaging is designed to be loaded and unloaded when dry.

The safety analyses described above require, notably, the following steps and verifications of the criteria below to be carried out before the package is shipped:

 the loaded radioactive material check must demonstrate compliance with all technical characteristics specified for authorised contents;

 the packaging must comply with the periodic inspections to be carried out;

 checking the various components of the packaging in order to verify that any defects meet the requirements of the chapter of the safety analysis report concerning packaging specifications;

 checking for the absence of unauthorised foreign bodies in the packaging;

 checking the correct position and closure of all components constituting the containment vessel;

 checking the presence of pail spacers inside the cavity;

 inspection of dose equivalent rates around the package, to validate their compliance with the regulatory limits;

 checking that the packaging is not contaminated, in accordance with regulatory limits;

 measurement of the radiation intensity 1 m away for determining the transport index;

 checking the regulatory compliance of packaging labelling and marking;

 the stowage of packages must comply with the criteria and requirements of the safety analysis report;

 checking that the mode of transport is suited to the transport index, the criticality safety index and the activity of the content.

8. PERIODIC MAINTENANCE PROGRAMME The maintenance programme planned during the use of the packaging is defined for a period of three years.

The maintenance programme includes:

 systematic inspection of the general condition of the packaging and replacement of any non-compliant component;

 replacement of containment vessel seals.

Form: PM04-4-MO-6 rev.02 Orano TN Identification: DOS-19-022728-005 E Version: 2.0 Page 14 of 14 Any packaging with one or more components not meeting the criteria specified in the maintenance programme must be withdrawn from service until the appropriate corrective action can be applied.

All components that have become non-compliant may be repaired or accepted as-is provided that a supplementary analysis demonstrates that the situation does not impair the conclusions of the Safety Analysis Report. If this is not the case, the component must be replaced.

9. QUALITY ASSURANCE PROGRAMME The transport regulations in force at the date of this document stipulate the application of quality assurance programmes for the:

x design; x manufacturing and testing; x use; x maintenance; x transport of packages containing radioactive materials.

These activities are undertaken by various parties (designer, owner, project manager, manufacturers, users, consignors, carriers, maintenance companies, etc.) who must all draw up suitable quality assurance plans and produce & conserve records of their activity.

10. REFERENCES

<1> International Atomic Energy Agency regulations for the Transport of Radioactive Materials -

Special safety requirements, SSR-6, see Chapter 00 for applicable edition.

Rules on design and testing in the applicable version of the IAEA rules are covered in the following applicable regulations:

x European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR);

x Regulations concerning the International Carriage of Dangerous Goods by Rail (RID);

x International Maritime Dangerous Goods code (IMDG code of the IMO);

x French Order of 29 May 2009, as amended, on the carriage of dangerous goods by road (TMD order);

x French Order of 23 November 1987, as amended, concerning the Safety of Shipping, division 411 of the attached regulations (RSN Order).