ML22271A810
| ML22271A810 | |
| Person / Time | |
|---|---|
| Site: | Orano USA |
| Issue date: | 08/03/2022 |
| From: | TN Americas LLC |
| To: | Division of Fuel Management |
| Garcia-Santos N | |
| Shared Package | |
| ML22271A128 | List:
|
| References | |
| A33010, L-2022-DOT-0007 | |
| Download: ML22271A810 (13) | |
Text
Non-proprietary version Form: PM04-4-MO-6 rev. 03 Orano NPS SAFETY ANALYSIS REPORT Unrestricted Orano APPENDIX 2.1-14 VARIATION IN THE MECHANICAL PROPERTIES OF SHELL AND SCREW STEELS BETWEEN - 40 °C AND °C FCC3/FCC4 Prepared by Checked by Identification:
DOS-19-021165-012-NPV Version 1.0 Page 1 / 13 Contents
- 1. Purpose 3
- 2. Impactonthemechanicalpropertiesoftheshellsteels 3
- 3. Impactonthemechanicalpropertiesofscrews(class) 7
- 4. Conclusion 9
- 5. References 9
ListofAppendices 11
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Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 2 of 13 Non-proprietary version Status of revision Version Date Purpose and record of revisions Prepared by/Checked by 1.0 See page 1 First issue
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
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- 1.
Purpose The purpose of this analysis is to evaluate, for FCC3 and FCC4 packages, variation in the mechanical properties of the steels forming the upper shell, the lower shell and their connecting screws over the
- 40 °C to °C temperature range, based on the standards and articles in references <1> to Erreur !
Source du renvoi introuvable..
- 2.
Impact on the mechanical properties of the shell steels 2.1.
Shell steels In accordance with chapter 1.4, the half-shells of the FCC3 and FCC4 packagings are made from steel, whose specifications are listed below:
Steels, ( and as per the former standard ),
as per standard <1> and steel as per standard Erreur ! Source du renvoi introuvable. for the shells, steels, as per standard Erreur ! Source du renvoi introuvable. for the shells, steel as per the former standard Erreur ! Source du renvoi introuvable. for the closure flange (or angle bar).
The steel structures helping to absorb energy during drops have thicknesses ranging from to mm. Accordingly, the properties of the steels are only investigated over this thickness range.
The temperatures considered will be those of the NTC, as per chapter 2.2, within the - 40 °C to °C range.
As the variation in mechanical properties between - 40 °C and + 20 °C is negligible, they are considered constant over this temperature range.
2.2.
Properties of and steel shells The chemical composition of the steels derived from standards <1> and Erreur !
Source du renvoi introuvable. is similar to that of the steels in the standard Erreur !
Source du renvoi introuvable., see the tables below. Further, the manufacturing methods of the steels used for the sheet metal and flats of these 3 standards match, so the metallurgical states of the and steel products are identical.
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 4 of 13 Non-proprietary version Further, the guaranteed mechanical properties of the or steels at ambient temperature are similar for the thickness classes (see tables of mechanical properties below derived from standards <1>, Erreur ! Source du renvoi introuvable. and Erreur ! Source du renvoi introuvable.).
This justifies using variation in conventional yield strengths Rp0.2 for the steels with temperature in standard Erreur ! Source du renvoi introuvable. to represent variation in Rp0.2 for the steels in standards <1> and Erreur ! Source du renvoi introuvable.,
particularly for temperatures between ambient and 100°C.
2.2.1. Yield strength of the shells As justified hereabove, the variation in minimum Rp0.2 for steels with temperature can be used to evaluate variation in steels. This variation is given by standard Erreur ! Source du renvoi introuvable. for steels.
On this basis, the relevant changes for steels are:
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 5 of 13 Non-proprietary version The Rp0.2 values for and steels are linearly interpolated from the previous table and given below for the 2 thickness classes considered:
2.2.2. Ultimate tensile strength of the shells The standards for and steels specify the minimum value of ultimate tensile strength Rm at 20°C. However, they do not specify any variation with temperature.
The relevant basic data is therefore:
Regarding the elevated temperature changes of the ultimate tensile strength, note that, according to the article in reference Erreur ! Source du renvoi introuvable. for a steel with a carbon content of %, ultimate tensile strength Rm decreases slightly over the 20°C to 100°C temperature range (see extract from article Erreur !
Source du renvoi introuvable. in annexe 1).
The decrease in Rm between 20°C and 100°C is conservatively considered to be identical to that of Rp0.2 in section 2.2.1.
The ultimate tensile strength will therefore be determined by considering the Rp0.2/Rm ratio as constant between 20°C and 100°C.
On this basis, for steels at °C and for a thickness mm, this gives:
Rp0.2 20 °C Rm 20 °C Rm °CRp0.2 °C
MPa For the thickness classes considered, the Rp0.2/Rm ratios at 20°C for and steels are as follows:
On this basis, the following minimum Rm values are deduced for the 2 thickness classes of and steels:
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Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 6 of 13 Non-proprietary version 2.3.
Properties of the mm thick angle bars made of steel The ambient temperature requirements in chapter 1.4 for the normalized forged steel used in the angle bars are raised with respect to Erreur ! Source du renvoi introuvable., for Rp0.2 and to a lesser extent for Rm:
These requirements approximate to those for the shell steels given hereabove. The properties of the and steels used for the shells can be re-used as:
The chemical composition of in Erreur ! Source du renvoi introuvable. is similar to that of the and steels, The mechanical properties are identical for the mm thickness at 20°C, The relative changes in the mechanical properties of the rolled products can be transposed to that of the forged products (the forgings have a more compact structure, therefore with higher mechanical properties than the rolled products).
The table below shows the chemical composition of the used for the angle bars:
On this basis, by similarity with and steels, the mechanical properties between
- 40°C and °C of used for the angle bars are considered identical to those of and steels and are as follows:
2.4.
Conclusion on the changes in shell mechanical properties The Rp0.2 and Rm of the shell steels as determined in the previous paragraphs over the - 40°C to °C temperature range are used to evaluate variation in energy absorption capacity with steel temperature. As a reminder, energy absorption capacity is equal to the area under the tensile curve determined according to the formula:
Area under the tensile curve Rp0.2 Rm A%/2 Rupture elongation A% is equal to % according to chapter 1.4.
The energy absorption capacity variation between - 40°C and °C is given by the following formula:
Energy absorption capacity variation Area °CArea 40 °C Area 40 °C The table comparing the changes in mechanical properties of steels from - 40°C to
°C for the relevant thickness classes is given below:
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Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 7 of 13 Non-proprietary version The table comparing the changes in mechanical properties of steels from - 40°C to
°C for the relevant thickness classes is given below:
The table comparing the changes in mechanical properties of steels from
- 40°C to °C for the relevant thickness classes is given below:
The above comparison tables can be used to verify the impact of temperature variation in steels on their respective energy absorption capacities. The decrease in energy absorption capacity remains less than 7%.
- 3.
Impact on the mechanical properties of screws ( class )
The M12 diameter screws used to join the two half-shells are made of steel or steel (class ).
Between - 40°C and 20°C, the variations in the mechanical properties of this steel are negligible; they will be considered constant over this temperature range.
At 20°C, the guaranteed data for class bolting as per standard Erreur ! Source du renvoi introuvable. made of quenched and tempered alloy steel is as follows:
Rp0.2 MPa, Rm MPa, steel is similar in chemical composition to grade of Erreur ! Source du renvoi introuvable.. The quenched and tempered conditions also overlap. The guaranteed mechanical properties at 20°C are quite similar for the applicable diameter class ( mm) as shown by the tables below.
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Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 8 of 13 Non-proprietary version As a result, the changes in the at-temperature mechanical properties of grade in ASTM as given by the code Erreur ! Source du renvoi introuvable. can be used to determine the yield strength Rp0.2 and the ultimate tensile strength of steel.
3.1.
Yield strength of the screws The relevant baseline data derived from Erreur ! Source du renvoi introuvable.
are therefore:
These elements lead to the following minimum Rp0.2 values for the hammer head screws diameter Ø mm made of :
3.2.
Ultimate tensile strength of the screws The code Erreur ! Source du renvoi introuvable. does not specify any minimum ultimate tensile strength Rm value at 20°C, nor any variation in this value with temperature.
Accordingly, the baseline data are the 20°C mechanical properties derived from standard Erreur ! Source du renvoi introuvable. for steel (as a reminder:
Rp0.2 MPa and Rm MPa).
Regarding variation in the ultimate tensile strength at high temperatures, and according to the article in reference Erreur ! Source du renvoi introuvable. for a steel with a composition similar to steel (i.e. with a carbon content of % and a chromium content of % - see extract from article Erreur ! Source du renvoi introuvable. in annexe 2), the ultimate tensile strength Rm decreases slightly from 20°C to 100°C.
As the Rp0.2 and Rm vary over this temperature range in a similar manner, the ultimate tensile strength will be determined by considering the Rp0.2/Rm ratio at 20°C derived from Erreur ! Source du renvoi introuvable. as constant between 20°C and 100°C.
For steel at 20°C specified in chapter 1.4, this gives:
Rp0.2 20 °C Rm 20 °C Rm 20°CRp0.2 20 °C
MPa These elements lead to the following minimum Rm values for the hammer head screws diameter Ø mm made of :
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Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 9 of 13 Non-proprietary version 3.3.
Conclusion on the changes in screws steel mechanical properties The Rp0.2 and Rm of the screws steels as determined in the previous paragraphs over the
- 40°C to °C temperature range, are used to evaluate the variation in energy absorption capacity with steel temperature. Energy absorption capacity is equal to the area under the tensile curve determined according to the formula:
Area under the tensile curve Rp0.2 Rm A%/2 Rupture elongation A% = % is derived from Erreur ! Source du renvoi introuvable. for steel at 20 °C.
The energy absorption capacity variation between - 40 °C and °C is given by the following formula:
Variation de la capacité dabsorption dénergie Area °CArea 40 °C Area 40 °C The table comparing the changes in mechanical properties of steel from - 40°C to °C is given below:
The above comparison table can be used to verify the impact of temperature variation in screws steel on the energy absorption capacity of the material. For this purpose, the ratio of the areas under the two tensile curves at the respective temperatures of 20°C and °C is determined. This ratio gives a decrease in energy absorption capacity of less than 7.5%.
- 4.
Conclusion Temperature variation between - 40°C and °C for the mechanical properties of the steels used for the shells and screws has a very slight effect on the energy absorption capacities of the materials (shells and screws) and therefore does not significantly impact the drop behaviour of the packaging.
Moreover, variation in the mechanical properties versus temperature is taken into account in chapter 2.1-11 with respect to the vertical drop behaviour of the packaging, demonstrating that the half-shells do not come apart in the worst-case configuration.
- 5.
References
<1>
<2>
<3>
<4>
<5>
<6>
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 10 of 13 Non-proprietary version
<7>
<8>
<9>
<10>
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 11 of 13 Non-proprietary version List of Appendices Appendix Title No of pages 1
Extract from article Erreur ! Source du renvoi introuvable.: Tensile Properties at Elevated Temperatures of Per Cent Carbon Steel 1
2 Extract from article <5>: Tensile Properties at Elevated Temperatures of Chromium-Vanadium Steel of the Type Per Cent Chromium, Per Cent Vanadium and Per Cent Carbon 1
TOTAL 2
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 12 of 13 Non-proprietary version EXTRACT FROM ARTICLE ERREUR ! SOURCE DU RENVOI INTROUVABLE.: TENSILE PROPERTIES AT ELEVATED TEMPERATURES OF PER CENT CARBON STEEL ANNEXE 1
Form: PM04-4-MO-6 rev. 03 Unrestricted Orano Orano NPS Identification:
DOS-19-021165-012-NPV Version 1.0 Page 13 of 13 Non-proprietary version EXTRACT FROM ARTICLE <5>: TENSILE PROPERTIES AT ELEVATED TEMPERATURES OF CHROMIUM-VANADIUM STEEL OF THE TYPE PER CENT CHROMIUM, PER CENT VANADIUM AND PER CENT CARBON ANNEXE2