ML22271A639
ML22271A639 | |
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Site: | Orano USA |
Issue date: | 05/04/2004 |
From: | Shaw D, Boyle R Framatome |
To: | Division of Fuel Management |
Garcia-Santos N | |
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ML22271A128 | List:
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A33010, EPID L-2022-DOT-0007 | |
Download: ML22271A639 (44) | |
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A Type of document: Design file FRAMATOME ANP 10, Rue Juliette Récamier 69456 LYON CEDEX 06 Class Nb pages: 32 NUCLEAR FUEL F Nb appendices: 7 DESIGN AND SALES DIVISION Title of document I 7 MODIFICATION OF RCC CONTAINERS CHOICE OF PROTOTYPE 2 DROP CONFIGURATIONS FOR REGULATORY TESTS KEYWORDS: CONTAINER - IAEA - TESTS FFXD Distribution FFTC For FCC safety report GED Purpose of distribution Base Number 1+1.pdf .pdf E
D 25.05.2004 17.10.99 l
l l
l l
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l CFC BPE M.E. ROBIN REV DATE AUTHOR CHECK MODIFICATIONS - OBSERVATIONS VALIDITY STATUS APPROVAL 229 K CLASSIF: INTERNAL IDENTIFICATION NUMBER U.D.: C 963 I TFXE 1111111~11111 DC 2 1 0 4 E0 I
NON-PROPRIETARY DOCUMENT TF 009 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE I/I REVISIONS DATE INDICE OBSERVATIONS 20.08.98 A First issue 18.09.98 B Incorporation of IPSN comments 08.04.99 C Inclusion of IPSN/DSIN comments expressed in the progress meeting of 12/03/99 and in fax SSTR/JYR/99.362 of 19/03/99 FRAMATOME ANP - Nuclear Fuel - Design and Sales Division 17.10.99 D Inclusion of comments made during preparatory meetings of 27/09/99 and 05/10/99 and plenary meeting of the Shipment Permanent Group of 11/10/99.
05.05.04 E Inclusion of comments made in letter DSIN/SD1/N°0156/2002 of 18/02/2002 and comments from FANC TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 1/32 CONTENTS
- 1. INTRODUCTION
- 2. ANALYSIS OF THE VARIOUS DROP CONFIGURATIONS 2.1. DEFINITION OF THE SAFETY COMPONENTS 2.1.1. 9m flat drop FRAMATOME ANP - Nuclear Fuel - Design and Sales Division 2.1.2. 9m vertical drop 2.1.3. 1m drop on bar 2.2. CHOICE OF THE ARRAY TO BE TESTED 2.2.1. 9m flat drop 2.2.2. 9 m vertical drop 2.2.3. 1m drop on bar 2.2.4. Other arrays 2.2.5. Rod channels 2.2.6. Array adopted for the tests 2.3. CHOICE OF DROP ANGLES 2.3.1. 9 m drop 2.3.2. 1m drop on bar
- 3. CONCLUSIONS TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 2/32 FIGURES Figure 1: Orientation conventions Figure 2: Drop on bar - Perforation of a plate Figure 3: Drop on bar - Shape of impacts Figure 4: Drop on bar - Equivalent bar diameter Figure 5: Container section - Position of centre of gravity and reinforcements Figure 6: Drop on bar - Possible azimuthal orientations Figure 7: Drop on bar - Choice of azimuthal orientations Figure 8: Drop on bar - Resulting angle as a function of longitudinal incidence FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Figure 9: Drop on bar - Influence of azimuthal orientation on bar/shell angle Figure 10: Drop on bar - Attack on door edge Figure 11: Drop on bar - Wall/bar and shell/bar angles for both configurations Figure 12: Drop on bar - Shear energy on hinges APPENDICES Appendix 1: Calculation of loads on the door connections Appendix 2: Influence of the drop height between a 16x16 and a 17x17XL assembly Appendix 3: Calculation of the incidence of an oblique drop on the shock absorber indentation Appendix 4: Comparison between shells of thickness l l mm and l l mm Appendix 5: Influence of longitudinal incidence for drops on bar Appendix 6: Comparison between 16x16-18x18 and 17x17 arrays for flat drop Appendix 7: Impact of 17x17 XLR guiding pins for vertical drop TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 3/32 REFERENCES
[1] TFX DC 2034: Description of the modifications to RCC model containers for the transportation of UO2 assemblies.
[2] TFXE DC 2087: Prototype Container NN°1, Drop Test Report.
[3] IAEA Regulations regarding the Transportation of Radioactive Materials.
1985 edition revised in 1990 - IAEA Safety Collection N°6.
[4] Directives for the enforcement of the IAEA Regulations regarding the Transportation of FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Radioactive Materials.
1985 edition revised in 1990 - Third edition - IAEA Safety Collection N°37.
[5] Experimental and numerical studies of impacts on stainless steel plates subjected to rigid missiles at low velocity. LEPAREUX, JAMET, MATHERON, LIEUTENANT, COUILLEAUX, DUBOELLE (CEA-IRDI) and AGUILAR (CEA-IPSN).
Article published in "Nuclear engineering and Design N°115 (1989) pages 105 to 112.
[6] TFX DC 2086: Modification of RCC Containers, Choice of Prototype Configuration within the scope of the regulatory tests.
[7] NVMD DC 98/578: Justification Report on the flat drop angle with slap-down.
[8] 229K 2600: Container for 2 UO2 fuel assemblies.
14 ft - 17x17 - (type XL) design - Sealed assembly
[9] 229K 2630: Container for 2 UO2 fuel assemblies.
14 ft - 17x17 - (type XL) design - Internal Equipment
[10] NCLME 50122001-5: RCC4 container - Shock absorber
[11] TFX/DC/2125: modification of RCC containers Choice of Prototype NN° 2 configuration within the scope of the regulatory tests Details of calculations
[12] TFX/DC/2214: Container for UO2 assemblies - Justification of FCC shell connection resistance following a 9 m vertical drop.
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 4/32
- 1. INTRODUCTION The objective of this report is to describe and justify the choice of the configurations which will be tested during the regulatory tests (§ 627 drops I and II of [3]) on an FCC4 container.
The concept is based upon the confinement of each of the transported assemblies in a cavity surrounded by a neutron-absorbing material (ref. [1]). [1]).
With the aim of a preliminary check on the soundness of this concept, a drop test campaign was run in early February 1998 (ref. [2]). The tested configuration was an FCC3 loaded with an l l assembly 1111 (l l) and a test load representative of a fuel assembly.
On completion of this test campaign and after taking into account the feedback from the testing and fabrication of prototype N°1, modifications were made to an RCC4; this container was named prototype FRAMATOME ANP - Nuclear Fuel - Design and Sales Division N°2. A campaign of regulatory tests was run in order to demonstrate, for the configurations requiring it, the suitability of the modified containers during the tests as defined in § 627 drops I and II of [3].
The configuration tested during the Regulatory Tests had to be conservative from the point of view of mechanical loadings on the safety components and lead to the worst-case situation from the package criticality safety standpoint.
From the point of view of the inertias and mechanical stresses involved, a high mass had to be chosen.
This led to the choice of the type FCC4 container loaded with a 14 ft fuel assembly. Several arrays correspond to this assembly length: 17x17XL/XLR, 16x16 and 18x18. The last 2 arrays (German products) have a mass slightly larger than the 17x17XL/XLR product (EDF and Belgium).
It should be noted that to date, nearly all the RCC4s are used for transporting 17x17XL arrays.
Remark: The mechanical calculations in this report are not design calculations but are intended to draw comparisons between several assembly designs under equivalent conditions.
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 5/32
- 2. ANALYSIS OF THE VARIOUS DROP CONFIGURATIONS The drop tests aim to demonstrate the suitability of the package safety components and to produce the worst-case geometrical configuration from a package criticality safety standpoint. The analysis to be conducted will enable us to define safety components, choose the type of assembly to be tested and determine the drop angles.
During this analysis, the three drop types will be reviewed:
x 9-meter flat drop, x 9-meter axial drop, x 1-meter flat drop onto a bar.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Orientation conventions are shown in Figure 1:
x Origin of the axes - passing through the centre of gravity of the internal equipment, x Longitudinal incidence angle: D (D=0: container horizontal),
x Azimuthal orientation angle: E (E=0: container resting on its pads).
2.1. Definition of the safety components 2.1.1. 9m flat drop For the 9m flat drop, the safety components are those whose failure would lead to:
x An increase in the cavity section, x The failure of the door fasteners (items 2 and 3 of [9]) on the frame (item 1 of [9]) and on the top (items 4 and 7 of [9]) and bottom (item 5 of [9]) plates, x The heterogeneity of the fuel rod array, x Degradation of the assembly thermal shield due to the doors opening, x The failure of the connection between the half-shells.
The safety components are therefore:
x The top and bottom plate connections with the frame and doors, x The door/frame connections, x The doors and frame themselves.
x The half-shell connection bolts.
The grid clamping pads do not need to be considered as safety-related components, at the most their failure would lead to an increase in the section of the assemblies equivalent to that of the neutron cavity. Their behaviour is accounted for in the hypotheses of the criticality analyses.
2.1.2. 9m vertical drop For the 9m vertical drop, the safety components are those whose failure would lead to:
x An increase in the cavity section, x The failure of the top or bottom plate fixings, TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 6/32 x The failure of the door/frame fixings, x Assembly buckling, x The failure in the half-shell connections.
The safety components are therefore:
x The shock absorber which reduces the loads applied to the assembly and connections, x The top or bottom plate connections with the frame and doors, x The door/frame connections, x The half-shell bolted connections.
The top pads (item 9 of [9] do not need to be considered as safety components as their failure could only lead to slipping of the assemblies which is taken into account in the criticality study hypotheses.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division 2.1.3. 1m drop on bar For the drop on bar, the safety components are those whose failure would lead to:
x An increase in the cavity section, x The failure of the door/frame fixings and on the top and bottom plates, x The tearing of a door or of the frame underside, x The heterogeneity of the fuel rod array, x Degradation to the assembly thermal shield due to the doors opening or being perforated.
The safety components are therefore:
x The top or bottom plate connections to the frame and doors, x The door/frame connections, x The doors and frame themselves.
The grid clamping pads do not need to be considered as safety-related components, at the most their failure would lead to an increase of the section of the assemblies equivalent to that of the neutron cavity. Their behaviour is accounted for in the hypotheses of the criticality analyses.
2.2. Choice of the array to be tested The comparison of the various arrays will centre on an evaluation of the behaviour of the safety components under load.
The 3 types of array transported in an FCC4 are:
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 7/32 x the 17x17XL/XLR1, x the 16x16, x the 18x18.
To take into account the possibility of transporting core components for the 17x17XL/XLR arrays, and to cover changes in the transported products which would result in a mass increase, we chose to make an 17X17XL assembly heavier by inserting l l rods into the guide thimbles, which leads to a mass 1111 increase of l l kg, i.e. a total mass of l l kg for this configuration.
Their main characteristics are:
Assembly 17x17XL/XLR 17x17XL 16x16 18x18 FRAMATOME ANP - Nuclear Fuel - Design and Sales Division
+l 1111 l rods Assembly mass (kg) 1111 l l 1111 l l 1111 l l 1111 l l Assembly section (mm x mm) 1111 l l 1111 l l Nozzle length (mm) 1111 l l 1111 l l 1111 l l Total spring length (mm) 1111 l l 1111 l l 1111 l l Active length (mm) 1111 l l 1111 l l Linear mass in active section (kg/mm) 1111 l l 1111 l l 1111 l l 1111 l l The section of the 16x16 and 18x18 arrays is greater than that of the 17x17, so the doors and housing for the 16x16 (and 18x18) will have a width l l mm greater than for the 17x17. Likewise, the frame width for the 16x16 (and 18x18) is increased by l l mm and its height by l 1111 l mm.
The overall length of the 16x16 and 18x18 assemblies is greater than for the 17x17XL, so the length of the doors and frame is increased by about l 1111 l mm.
The characteristics of the containers will therefore be as follows:
Assembly 17x17XL 16x16 and 18x18 1111
+l l rods Housing section (mm x mm) 1111 l l 1111 l l Shell mass (kg) 1111 l l 1111 l l Suspended mass without assemblies (kg) 1111 l l 1111 l l Suspended mass with assemblies (kg) 1111 l l 1111 l l 1
The 17x17XLR assembly has the same geometrical characteristics as the 17x17XL assembly, with the exception of guiding pins on the top nozzle and the longitudinal positioning of the grids.
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 8/32 2.2.1. 9m flat drop 2.2.1.1. Strength of the door plates The test campaign, conducted in February 98 on an RCC3 container modified and loaded with a 17x17 1111 l l assembly, showed that the assembly grids deformed laterally (ref. [2]). [2]).
The linear masses of the 17x17 and 17x17XL/XLR assemblies are equivalent; so the observations made for the grids of prototype N°1 remain valid for prototype N°2.
Regarding prototype N°2, it should be noted that the latter has been weighted by the addition of l l 1111 supplementary rods and that the slap-down is designed to apply maximum loading, which makes the test bounding.
In this situation, the forces of inertia are reduced to a pressure exerted on the door partition. The FRAMATOME ANP - Nuclear Fuel - Design and Sales Division following table shows the ratio of the linear mass of the assembly active section to the cavity width for prototype N°2.
Assembly 17x17XL 16x16 and 18x18 1111
+l l rods Linear mass in active section (kg/mm) 1111 l l 1111 l l Active length (mm) 1111 l l 1111 l l Bearing surface width (mm) 1111 l l 1111 l l Mass / bearing surface ratio 1111 l l 1111 l l
Conclusion:
the lower bearing surface width of 17x17XL leads to a larger stress in the door partition over a greater length.
2.2.1.2. Strength of the door/frame connections The door connections are spaced across the grid area; the loads on the hinge pins are therefore generated by the mass of an assembly span and a door span (The distribution of forces is achieved by taking the door section to be a half-gantry with 2 joints, the assembly exerting a uniform pressure on one of the beams).
The force is taken up by the hinge pins (item 12 of [9]) by shearing on 2 sheared sections Ø l 1111 l or at the locking pins (item 14 of [9]) by 2 sheared sections Ø l l. Details of the calculations are given in Appendix 1 and the results indicated in the table below.
Assembly 17x17XL 16x16 and 18x18
+l 1111 l rods 1111l g Security coefficient on the hinge pins at l 1111 l l 1111 l l Security coefficient on the locking pins at l 1111l g 1111 l l 1111 l l
Conclusion:
the increased linear mass of 16x16 (or of 18x18) leads to stresses in the same order of magnitude, and in the range of uncertainty of the analysis, as for the 17x17XL loaded with l 1111 l rods.
The behaviours are equivalent for the locking pins and hinge pins.
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 9/32 2.2.1.3 Opening of gaps between doors and frame Slap-down during the flat drop is designed to apply maximum loading and to widen the gaps between doors and frame by bowing and warping of the internal equipment components.
Computation of overall bowing: Whether for a 16x16-18x18 or 17x17 array configuration, the frame and doors can be considered as slender beams 2 in that the ratio between the height of the beams and their length is greater than l l 3. The behaviour of the internal equipment components is consequently linear and no warping or other phenomenon is expected.
Regarding the 16x16-18x18 array configuration, the increase in the cross-sectional geometrical dimensions of the doors and frame leads to an increase in their inertia. The bending calculation in Appendix 6 demonstrates that this increase in inertia takes precedence over the increase in mass and length of the internal equipment. The 16x16-18x18 array configuration therefore bends less than the FRAMATOME ANP - Nuclear Fuel - Design and Sales Division 17x17 array, which lessens the risks of the gaps opening between the doors and frame.
On the other hand, the calculation in Appendix 6 shows that the velocity of the second impact will be less for the 16x16-18x18 arrays due to the increased inertia of their internal equipment. This factor also helps to minimise the bow in this configuration.
Computation of local bowing: calculation of the maximum longitudinal bowing applicable to a 18x18 door shows that the corresponding compression stress is smaller than Eulers critical load. This remains true both for a door section, between two ribs, or for the upper core of the door of this section, as demonstrated in Appendix 6.
The flat drop of an FCC4 prototype 2 container cannot induce a widening of the gap between doors and frame as demonstrated by the drop tests carried out on prototype 1.
Conclusion:
the configuration of the internal equipment in the 17x17 arrays is more conservative than for the 16x16-18x18 arrays.
2.1.2.4 Special case - loading a single assembly Filling just a single cavity of the internal equipment leads to a significant decrease in the mass of this system. The mechanical loadings on the plates and door/frame connections are identical on the loaded side. The bow of the internal equipment will be smaller than for double loading.
Conclusion:
The double-load configuration of the internal is more conservative than the single-load configuration.
2.2.2. 9 m vertical drop 2.2.2.1 Strength of the top and bottom plate connections The failure of the bottom plate connections (item 4 of [9]) requires the shearing of l l locking pin sections (item 15 of [9]) Ø l l (l l double shears) or of l 1111 l hinge pin sections (item 8 and 11 of 1111
[9]) Ø l l and the tensile failure of l l bolts M20 (item 16 of [9]).
2 A slender beam is a beam whose behaviour is assumed linear throughout its structure.
3 To be slender, a beam must have a ratio greater than l l for a solid structure and l l for a structure consisting of thin plates.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 10/32 The permissible double shear limit for a locking pin Ø l l is l l daN, that of a hinge pin Ø l l is l l daN and the limit tensile load for a M20 bolt ( l l) is l l daN. The total limit load is therefore IIIIIIII about l l daN.
The failure of the doors/head plate connections calls for the shearing of l1111l locking pin sections Ø 11111111 l l (l 1111 l double shears) or l l hinge pin sections Ø l l; the connection between the 2 plates is IIIIIIII assumed to be unloaded. The total limit load is therefore about l l daN.
The failure of these connections is based on the following hypotheses:
x The 2 assemblies being supported by the plate, x The frame remaining in a fixed position, x The plate being able to move longitudinally.
For an axial drop, the cradle / frame / door / plate combination moves in the same motion and bears down on the axial shock absorber. It is therefore noted that the last two hypotheses mentioned above FRAMATOME ANP - Nuclear Fuel - Design and Sales Division do not apply and that consequently the shear stresses in the locking pins are very small.
This was verified during the tests on the l1111 l container where the mobile assembly bore down on the shock absorber which was uniformly pushed down [2].
Conclusion:
The type of array has no effect on the behaviour of the plate / door top side connections and plate / door / frame bottom side connections.
2.2.2.2 Performance of the plates Owing to the presence of an axial shock absorber, the bearing-down of the assembly on the plate inner face is fully compensated by the bearing-down of the plate outer face on the axial shock absorber.
This was verified during the tests on the l l container, where no bending of the top plate was recorded [2].
Conclusion:
the type of array has no effect on the behaviour of the top and bottom plates.
2.2.2.3 Performance of the bolted connection of the half-shells To analyse the risk of the two half-shells separating, the maximum drop impact energy must be considered. The incidence angle (D) producing the maximum impact energy is obtained when the centre of gravity of the connected half shells configuration is vertical to the impact, thus D'= l l° (Figure 1).
Report [12] shows that there is no risk of separation of the 2 half shells in case of a vertical drop.
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 11/32 2.2.2.4 Special case of the 17x17 XLR assembly It is noted in Appendix 7 that the guiding pins of the 17x17XLR assemblies buckle at a load well below that generated in the shock absorber crushing phase. Indeed, during a vertical drop of a 17x17XL assembly, the deceleration induced by the crushing of the internal equipment on the shock absorber is on the order of l l g. In these conditions, the assembly sustains, at the top nozzle legs, a loading in the order of l l daN which is comparable with the l l daN needed to buckle the pins of the 17x17XLR assemblies.
Conclusion:
the presence of guiding pins on the 17x17XLR assemblies has little influence on the vertical drop behaviour of the assembly.
2.2.3. 1m drop on bar FRAMATOME ANP - Nuclear Fuel - Design and Sales Division In this drop configuration, the maximum damage objective means aiming for shell perforation and bar penetration towards the fuel confinement doors.
The mass of an FCC4 shell is estimated to be l 1111l kg.
The energy needed to perforate a l 1111 l mm thick steel plate with a bar l 1111l mm in diameter with a zero drop angle is estimated to be approximately l 1111 l KJ - ref. [5].
Furthermore:
x There is some coupling between the internal structure and the shell through the shock mounts, so the mass to be taken into account is greater than that of the shell, x The drop occurs with a slight incidence, causing the shell to tear.
The result is complete perforation of the shell by the bar. This was observed during the February 1998 test campaign (ref. [2]).
Remark: There are a few special containers (l 1111 1111 l to l l) for which the shell has a plate thickness of 1111 l l mm. Appendix 4 shows that the bar impact energy on the door for a shell thickness of l l mm is less than that produced for a thickness of l1111 l mm. The l 1111 l mm case therefore bounds the l l mm case.
The drop continues over some distance until the impact between the bar and the first plate of the door.
This further drop distance is slightly reduced for 16x16 (or 18x18), by a minimum height of about l 1111 l
mm corresponding to the increase in section of the array and thus of the cavity (this height is minimum when the bar attacks the door face without incidence). In energy terms, this corresponds to an equivalent mass reduction on the order of l 1111 l kg (see detail of calculations in Appendix 2).
The presence of the resin between the two walls distributes the load transmitted by the bar across the full width of the internal plate and results in pressure loading across this plate.
This was confirmed by tests on a l 1111 l container where the bar impact zone on the outer face of the door (middle of face, surface indented about l 1111 l mm in diameter) resulted at the internal face in an indentation spread over the whole door width.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 12/32 Assembly 17x17XL 16x16 and 18x18
+l1111 l rods Total mass exc. shell (kg) 1111 l l 1111 l l Equivalent mass (kg) 1111 l l 1111 l l Internal bearing width (mm) 1111 l l 1111 l l Mass / bearing width ratio 1111 l l 1111 l l It must also be noted that the literature (ref. [5]) indicates that the ultimate perforation load variation of FRAMATOME ANP - Nuclear Fuel - Design and Sales Division a plate is linear with the deformation (indentation). By integration, it is therefore shown that the deformation energy varies with the l ll l deformation. As a result, the deformation varies with l ll l this energy. Without taking into account the increased door width of 16x16 or 18x18 (conservative hypothesis), a penetration depth l 1111 l % higher for 16x16-18x18 would be obtained, i.e.
less than one half-millimetre (l l mm of indentation in the internal portion for the tests [2] on the l l container with bar impact on a door face). This difference cannot be assessed in terms of geometrical examination of the neutronic cavity.
Conclusion:
the smaller door internal surface for 17x17XL loaded with l 1111 l crayons than for 16x16 (or 18x18) leads to a slightly higher stress; the differences in impact energy between the 17x17XL 1111 loaded with l l rods and the 16x16 (or 18x18) are less than l 1111 l %.
2.2.4. Other arrays The possibility of running the Regulatory Tests on the basis of a modified RCC3 could be considered.
The possible configurations would then be as follows:
1111l, mass 1111 x 17x17, length l l l kg (preliminary tests),
x 15x15, mass 1111 l l kg, x 14x14, length 1111 l l, mass 1111 l l kg, x 14x14, length 1111 l l, mass 1111 l l kg.
The masses of the assemblies considered here-above are much smaller than for the 17x17XL loaded 1111 with l l rods and do not lead to a conservative configuration.
The foregoing analysis is not therefore called into question by the choice of another array.
2.2.5. Rod channels Non assembled rods will be shipped in a rod channel positioned within the neutron cavity (1 channel per cavity).
1111
~
The maximum mass of an assembly is l l kg (17x17XL assembly loaded with l l rods), while the maximum mass of a channel is l l kg. In terms of mass, these two configurations are therefore equivalent.
The behaviour of the rods will be no different from that observed for an assembly (uniform bearing on the door, possible differential slipping).
TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 13/32 These observations lead us to rule out the choice of a rod channel for the Regulatory Tests.
2.2.6. Array adopted for the tests 1111 The cases analysed above lead us to adopt the 17x17XL assembly loaded with l l rods in its guide thimbles for the regulatory tests on an FCC4 container. This is the worst case in that the maximum mass content is inserted into the least rigid internal equipment structure.
The container will therefore be loaded with a 17x17XL assembly loaded with l l rods in its guide thimbles and with a test load representative in mass and dimensions.
2.3. Choice of drop angles 2.3.1. 9 m drop FRAMATOME ANP - Nuclear Fuel - Design and Sales Division For the 9 m drop, 2 configurations are possible:
x flat drop with slap-down, x vertical drop.
We shall now analyse these 2 configurations to find the one which gives maximum loadings for the package.
2.3.1.1. Flat drop with slap-down During flat drop with a longitudinal incidence, it is generally at the second impact that the velocity is highest. We determined this incidence by calculation.
The drop angles are calculated by PLEXUS, a fast dynamic module of CASTEM (CEA), as described in report [7] which we summarise below.
The frame is modelled by finite beam elements. The wire frame mesh size was defined using a parametric study.
The initial calculation conditions are as follows:
x Frame positioned l 1111l m from the ground (assumed infinitely rigid),
x Initial velocity of 1111 l l m/s ( giving an initial impact at 1111 l l m/s corresponding to a 9m drop),
x longitudinal incidence D which is varied at each calculation, x zero azimuthal orientation E which can be varied once the longitudinal incidence is determined.
A series of calculations with zero azimuthal orientation E shows that the maximum impact velocity is obtained at the second impact with a longitudinal incidence D= l 1111 l °, the impact velocity is thus l 1111 l
m/s.
A second series of calculations is performed for an azimuthal orientation E of 45° and 90°, with in each case a longitudinal incidence D of 10°, 15.2° and 25°. These calculations all give second-impact velocities less than l l m/s (D=l l ° and E= l l °). This result is confirmed by a physical approach which shows that the maximum effect is obtained with an azimuthal orientation corresponding to the minimum bending inertia (E=l 1111 1111 l °or l l °).
Conclusion:
for the flat drop with slap-down, the worst-case configuration is obtained for D= l l° 1111 1111 and E= l l °or l l °. The configuration corresponding to E= l1111 l ° leads to an impact on the upper portions of the doors and therefore to their maximum loading (no protective features between the doors and the outer shell).
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 14/32 2.3.1.2. Vertical drop During the preliminary tests (ref. [2]) on the FCC3 container prototype N°1, the vertical drop test showed very good shock absorber behaviour (ref. [10]) and control of its design.
Due to manufacturing and operational demands, we were obliged to alter the shock absorber design in response to the feedback from the tests (ref. [2]) on the FCC3.
In the table below, we compare the characteristics of the shock absorbers on prototype N°1 with those planned for prototype N°2.
FCC3 FCC4 Change between Prototype N°1 Prototype N°2 FCC3 and FCC4 Balsa thickness (mm) 1111 l l 1111 l l 1111 l l 1111 1111 1111 FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Suspended (sprung) mass (kg) l l l l l l Contact area (cm²) 1111 l l 1111 l l 1111 l l Crushing on housing side (mm) 1111 l l 1111 l l 1111 l l Crushing on flange side (mm) 1111 l l 1111 l l 1111 l l Protrusion of lifting eye (mm) 1111 l l 1111 l l 1111 l l Minimum remaining thickness (mm) 1111 l l 1111 l l 1111 l l Crushing rate outside flange (%) 1111 l l 1111 l l 1111 l l Crushing rate at flange (%) 1111 l l 1111 l l 1111 l l x
x The following values listed in columns 2 and 3 are those indicated on the container drawings:
l l l; Suspended (sprung) mass: maximum theoretical mass of the configuration including the internal equipment of the container and its load contents.
x Contact area: minimum theoretical area of contact between the internal equipment and the shock absorber.
The following values, listed in column 2, are those given in the expert assessment report of the shock absorber based on the measurements and observations made after the drop test:
x Crushing on housing side: crushing of the balsa shock absorber observed after the test, on the
.w- ...
absorber side facing the head plate. This value is obtained by measuring the residual l l thickness between the indentation of the suspended mass and the indentation on the flange side 1111 (here l l mm as measured). The result is l l- l l=l l mm. To this value is substracted the depth of the flange indentation (here l l mm measured l l). The resulting indentation is 1111 1111 1111 l l-l l=l l mm which includes clearly the suspended mass indentation but also a possible overall crushing of the shock absorber.
x Crushing on flange side: crushing observed on the shell side face of the l 1111 l shock absorber. On this face is observed the indentation of the two half shells connection flange.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 15/32 x Protrusion of lifting eye: additional indentation due to the presence, on the head side, of the lifting eye protruding from the head plate. The strength of this lifting eye being particularly high with regard to the shock absorber, the value of the protrusion is considered in a very conservative manner.
x Minimum remaining thickness: corresponds to the remaining balsa thickness between the deepest part of the indentation of the lifting eye and that of the flange. The value is obtained by subtracting 1111 the lifting eye depth (here l 1111 l mm) from the residual balsa thickness (here l l mm).
N.B.: these values were obtained by destructive examination (dissection) of the shock absorber and are distinctive of the balsa itself.
The same values given in column 3 for the FCC4 were extrapolated from the observations made on the FCC3.
x Crushing on housing side: this value is increased according to the FCC4 characteristics. The addition of an increased mass dampened on a smaller area corresponds to a l 1111 l % increase in FRAMATOME ANP - Nuclear Fuel - Design and Sales Division crushing. Assigning the whole increase solely to the crushing on the housing side corresponds to the fact that most of the impact energy is absorbed on that side.
x Crushing on flange side: This value remains unchanged due to the flanges being of a similar size.
When the flange impacts the shock absorber, the latter will have made full-area contact with the target. Considering the measurement mode, the value of the corresponding indentation will be shifted to the other side of the shock absorber.
x Protrusion of lifting eye: Using the corresponding FCC4 value.
x Minimum remaining thickness: result obtained by subtracting all the indentations considered from 1111 1111 1111 1111 1111 the initial thickness, so l l-l l-l l-l l= l l mm.
This reasoning establishes a ratio of proportionality between the indentation, the energy to be absorbed and the absorbing area. The ratio calculation method disregards the fraction of energy that has been absorbed within the flange and the lifting eye indentations. As such, l 1111 l % of the energy fraction absorbed at flange and lifting eye level is disregarded. In view of the small areas concerned, this fraction remains low (in the ratio of areas). This part will reduce the remaining thickness, which 1111 however still shows largely positive (l l mm to l1111 l mm) and is, in any case, capable of absorbing this approximation.
During an oblique vertical drop, the shock absorber would be pushed down in a trapezoidal section, as shown in Figure 2 of Appendix 3. The table here-above shows that in the case of vertical drop without 1111 inclination, there remains a minimum thickness of l l mm before interference between the lifting eye and the external flange, and the maximum acceptable indentation is therefore l We analyse here-under the angles which could lead to maximum indentation.
1111 l mm (l 1111 1111 l + l l).
The deformed l l volume is constant for the same energy irrespective of the inclination angle, the indentation width is as for the internal equipment (l1111l mm) and remains constant, so the deformed 1111 section will remain constant irrespective of its shape and will be l l mm² (see Appendix 3 Figure 1) as for the drop without inclination.
The calculations and the table in Appendix 3 show that with an angle of up to l 1111l ° the indentation 1111 will be less than l l mm. So there is no risk of the internal equipment interference during a vertical 1111 1111 drop at an inclination of up to l l °. The inclination leading to maximum impact energy is l l ° and is therefore covered by this approach.
While having a higher crushing rate, the shock absorber of the FCC4 will have a remaining minimum remaining thickness l l mm greater than for prototype N°1, which rules out any risk of internal equipment interference.
To sum up, the low loading of the connections in vertical drop conditions, as shown in § 2.2.2., the satisfactory behaviour and the control of the shock absorber design, all show that the vertical drop is not a conservative configuration.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 16/32 Remark: the extra mass of about l1111 l kg between that of the internal equipment used in the 16x16-18x18 arrays and that of the 17x17 arrays will induce additional indentation of the shock absorber in 1111 the order of l 1111 l % or about l l mm. Taking into account the wide margins, this extra indentation is negligible and the oblique vertical drop case remains covered (see table in Appendix 3).
2.3.1.3. Conclusion The configuration adopted for a 9 meter drop is a flat drop with a longitudinal incidence of 1111 D= l l ° and an azimuthal angle E= l 1111 l °.
2.3.2. 1m drop on bar During the drop on bar, the aim is for maximum damage of the safety components, as defined in § 2.1.3.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division To obtain maximum damage, the impact energy on the internal equipment must be maximum; this means that:
x The bar axis of impact must pass through the centre of gravity of the internals, x The outer shell must offer minimum resistance.
The centre of gravity of the internal equipment (with 2 assemblies) is l1111 l mm above the lower plate of the frame (see drawing ref. [9]) which, given its position in the shell, places it l l mm above the geometrical centre of the shell as shown in Figure 6. Longitudinally, the centre of gravity is located l l mm from the bottom end of the internal equipment, i.e between grids 5 and 6 of the assembly -
thus l l mm from the strengthening beam located in the vicinity of grid 6.
2.3.2.1. Analysis of the effect of the bar inclination When the bar angle makes an angle with the normal to the impacted surface, the impact shape and the perforation mode are no longer circular as with a null angle.
We shall now simulate this phenomenon, replacing the inclined bar with a vertical bar of smaller equivalent diameter and whose section corresponds to the projected surface of the impact, which corresponds to the start of plate perforation as shown in Figure 2.
Figure 3 shows the 3 types of impact shape that obtained at the moment of perforation, as a function of plate thickness and of the bar angle with the normal to the plate surface. These 3 types of shape are:
x Impact area less than a half-ellipse, x Impact area greater than a half-ellipse, x Impact area equal to a total ellipse.
Starting with these impact areas, we determine an equivalent circular bar with an impact axis merging with the normal to the plate surface and having the same impact area (the curves in Figure 4 give equivalent bars for varying plate thicknesses and show that the equivalent bar diameter decreases rapidly with the small angles before reaching a plateau).
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N° TFXE DC 2104 E0 A
FRAMAT OMEANP REV. E PAGE 17/32 2.3.2.2. Choice of azimuthal orientation When a vertical cross-section is made of the container is made at its centre, it can be seen that there are several long parts which may obstruct the bar and prevent it from reaching the safety components, defined in § 2.1.3., of the internal equipment. These parts, shown in Figure 5, are:
x The 2 shell stringers in the lower section, x The flanges between the 2 shells, x The shock mount supports, x The reinforcing plate in the upper section of the shell, x The longitudinal angle bars of the cradle, x The reinforcement in the lower section of the frame.
If the aim is to avoid these parts and have the axis of the first bar impact point passing through the FRAMATOME ANP - Nuclear Fuel - Design and Sales Division centre of gravity of the internal equipment to maximise the energy at impact on this system, there is a need to avoid certain azimuthal orientations of the container as indicated in Figure 6 and which are:
x 0° to 22°: no interference with the reinforcements of the lower shell, but the bar will impact the reinforced lower section of the frame, x 22° to 42°: interference with the stringers in the bottom portion of the lower shell, x 42° to 51°: no interference with the reinforcements of the lower shell, but the bar will impact the reinforced lower section of the frame, x 51° to 90°: interference with the shock mount support integral with the lower shell and with the longitudinal angle bar of the cradle, x 139° to 180°: interference of the bar with the reinforcing plate (th. l1111l mm) of the upper shell.
The foregoing analysis shows that the only possible azimuthal orientations for the drop on bar are between l1111 1111 l ° and l l ° which gives 4 cases to be analysed as shown in Figure 7; the analysis is 1111 initially made for a longitudinal incidence D= l l °.
x case N°1 D= l l °, E= l l °: the bar will impact the upper part of the door l 1111 l mm from the axis of symmetry of the container; the bar makes an angle of l l ° with the normal to the door, with the objective of perforating the door and achieving maximum loading of the closing hinge pins.
1111 The impact is felt about l l mm from the central edge of the door and closing hinge pins and about l l mm from the door reinforcement situated at grid 6. For a bar axis making an angle of l l ° with the normal to the door, the curves in Figure 4 show that the equivalent bar diameter is minimum, irrespective of the thickness.
If the aim is to directly impact the closing hinge pins, this means that the bar axis must make an angle of about l1111 l ° with the normal to the door and that the axis of the first impact must pass l1111 l mm from the centre of gravity of the internal equipment. With an angle of l 1111 l ° the risk of the bar skidding across the door wall is high and, further, the offset of the impact axis with the centre of gravity will start the package rotating. The impact energy on the hinge pins will not therefore be maximum, but this configuration is the only one which enables the bar to directly attack the hinges.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 18/32 x case N°2 D= l l °, E= l l °: the bar will impact the door corner, with the objective of deforming the fuel assembly housing section.
The tests ([2]) run on prototype N°1 showed that the doors were suitable for this loading (low deformation inside the housing). Further, in this configuration the hinges and hinge pins share the loads, while in case 1 only the hinge pins takes up the loads as they are close to the impact point.
x case N°3 D= l l °, E= l 1111 l °: the bar will impact the lateral part of the door, l l mm from the axes of rotation of the doors; the bar axis makes an angle of l 1111 l ° with the normal to the door, with the objective of applying the maximum loading on the door hinges. This configuration is the only one which applies maximum loading on the door hinges while avoiding the door reinforcements (see Figure 5), but as the impact point is not located close to the hinges, the latter will be less loaded than the hinge pins in case N°1; as the hinges and FRAMATOME ANP - Nuclear Fuel - Design and Sales Division hinge pins have equivalent mechanical properties, case N°1 covers case N°3.
The risk of door perforation in this configuration is much lower than in case N°1 owing to the smaller angle (l1111l ° instead of l1111l °) of the bar axis with the normal to the door; indeed, Figure 4 shows that, irrespective of wall thickness, the equivalent bar diameter will be larger in case N°3.
x case N°4 D= l l °, E= l l °: this case is reviewed since it corresponds to the maximum azimuthal orientation that can be given to the package, as stated in the foregoing. The bar will impact the lateral part of the door, with the bar axis making a zero angle with the normal to the door and the axis passing through the centre of the circular impact offset l 1111l mm from the centre of gravity of the internal equipment. In this situation, the package will start rotating, which minimises the impact energy, and also the bar equivalent diameter will be equal to its actual diameter, reducing the probability of tearing the door plate. Case N°1 therefore covers case N°4 as regards the loading of the hinge pins and door.
Conclusion:
The azimuthal orientation which will apply maximum loading to the safety components is obtained for 1111 case n°1: D= l 1111 l ° and E= l l °.
However, owing to geometrical constraints, the configurations analysed in the foregoing do not make it possible to directly attack with maximum energy (axis of impact passing through the centre of gravity) a safety component whose failure could lead to an increase in the assembly housing section, due either to the rupture of a door / frame connection or to a door plate being ripped off the reinforcements holding the connection points.
The analysis of the possibilities of attacking a connection with the possibility of increasing the housing section shows that only attack on the upper connection is possible without the axis of impact moving too far from the centre of gravity: a lateral attack on the bottom section would lead to reduction in the housing section and an attack by the lower shell is not possible as stated in § 2.3.2.2.
The geometrical constraints therefore lead us to select, as a second step, the configuration shown in Figure 10 with an angle of l1111 l ° from the mating surface.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 19/32 2.3.2.3. Choice of the longitudinal incidence of the packaging The longitudinal incidence D that is given to the packaging has an influence on the resulting angles made by the bar axis with the normal to the internal equipment wall and the bar axis with the container shell. This incidence cannot exceed l 1111l ° as, in this configuration; the packaging touches the ground before impacting the package door.
Depending on the drop configuration, the packaging axes of rotation differ:
For drop configuration N°1, whose objective is to shear the hinge pins, the bar must target this hinge.
The longitudinal incidence and azimuthal orientation therefore be achieved by rotating the packaging about the point of impact on the door.
For drop configuration N°2, whose objective is door perforation with maximum energy, the bar attack must pass through the centre of gravity. The longitudinal incidence and azimuthal orientation are achieved by rotating the packaging about its own centre of gravity.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division The calculation of the resulting angles between the bar and the wall, between the wall and the shell and for the two drop configurations is described in Appendix 5.
For drop configuration N°1, the increase in the longitudinal incidence makes it possible to slightly decrease the shell perforation energy but induces a transverse component which reduces the shear loading on the hinge. The impact energy of the bar on this hinge is proportional to the loads applied on the latter, so the impact energy varies with the cosine of the longitudinal incidence. The resulting energy, in other words the kinetic energy minus the shell perforation energy, is then maximum in shear for a null longitudinal incidence (Figure 12).
For drop configuration N°2, the longitudinal incidence has no effect on door perforation: for the angle 1111 1111 range between l l ° and l l ° (Figure 11), the equivalent bar diameter is minimum (Figure 4). The impact energies are therefore equivalent.
However, the increase of this incidence enables the shell perforation energy to be decreased: the impact angles obtained between the shell and the bar (Figure 11) vary between l l ° and l l °.
Now, in this value range, the equivalent bar diameter decreases. This decrease implies a significant drop in the shell perforation energy, whose minimum value is reached for a longitudinal incidence of 1111 l l °.
Nevertheless, a l1111 l ° longitudinal incidence is chosen as it eliminates the risk of the shell impacting with the ground. Moreover, the shock mounts can have an influence on the shell motions after impact against the shell. In addition, the variation in the energy of impact with the door between an angle of l l ° and l l ° is negligible (less than l l %). Consequently, the choice is for a longitudinal incidence of l l ° and an azimuthal orientation of l l °.
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A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 20/32 2.3.2.4. Loading a single assembly Impact of the bar on the door:
the case of double loading covers that of single loading in that the bar impact on the door passes through the container centre of gravity. The risks of door perforation will be larger for double loading.
Impact on the hinges:
In comparison to the double loading case, the dissymetrical loading induces a shift of the centre of gravity of the loaded FCC packaging configuration: the center of inertia shows a shift of l 1111 l mm (axis X) on the side of the remaining assembly, but is also lowered by l 1111l mm (axis Y) longitudinally to the plane of symmetry of the cavities. This leads to a distancing of the center of gravity from normal to the bar which, as a consequence, decreases the drop impact effects. Furthermore, the significant mass decrease in this loading configuration induces a diminution of the bar impact energy on the door hinges. These two effects concur in decreasing the impact energy, which enables us to conclude that FRAMATOME ANP - Nuclear Fuel - Design and Sales Division the drop of the container loaded with two assemblies is really the most conservative configuration.
2.3.2.5. Conclusion The configurations adopted for the drop on bar are:
x a drop with a longitudinal incidence of D= l l °, an orientation of l l ° from the mating surface (impact on the door edge greater than close to a connection).
x a drop with a longitudinal incidence of D= l 1111 l °, an azimuthal angle E= l 1111 l ° and l l mm from the bottom end of the internal equipment (impact on the upper part of the doors l l mm from grid 6) which will lead to maximum loading of the door closure hinge pins and to the maximum perforation risk.
- 3. CONCLUSIONS The evidence presented in the previous paragraphs show that for the drop configurations in the Regulatory Tests, the use of a 17x17XL assembly loaded with l 1111 l rods in its guide thimbles covers all transported assembly types. This is the worst case in that the maximum mass content is inserted into the least rigid internal equipment structure.
The 17x17XL assembly (AFAXL design destined for EDF reactors) was thus chosen for the configuration of the prototype tested during the Regulatory Tests.
For reasons of representativity in terms of lateral stiffness and shear behaviour, the mock-up will be built with a depleted uranium base (this choice was already made for the l 1111 l configuration tested in February 1998).
The container will therefore be loaded with a 17x17XL assembly comprising l l rods in its guide thimbles and with a representative weight in terms of mass and dimensions.
The drop configurations adopted for the tests are:
x a drop on bar with a longitudinal incidence of D= l l °, an orientation of l l ° from the mating surface.
1111l °, an azimuthal angle E=1l111l ° and 1111 x a drop on bar with a longitudinal incidence of D= l l l mm from the bottom end of the internal equipment, x a 9m flat drop with a longitudinal incidence of D= l1111l ° and an azimuthal angle of E=1111 l l° TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 21/32 The drops on bar will be performed first as they call for very high accuracy of the impact point, which would no longer be the case after the 9 m drop.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 22/32 FIGURE 1 Orientation conventions Vertical drop Flat drop FRAMATOME ANP - Nuclear Fuel - Design and Sales Division PROPRIETARY PICTURE PROPRIETARY PICTURE TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 23/32 FIGURE 2 Drop on bar Perforation of a plate PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 24/32 FIGURE 3 Drop on bar Shape of impacts PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division FIGURE 4 Drop on bar Equivalent bar diameter PROPRIETARY PICTURE FIGURE 5 Container section Position of centre of gravity and reinforcements TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 25/32 PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 26/32 FIGURE 6 Drop on bar Possible azimuthal orientations PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 27/32 FIGURE 7 Drop on bar Choice of azimuthal orientations PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 28/32 FIGURE 8 Drop on bar Resultant angle versus longitudinal incidence PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 29/32 FIGURE 9 Drop on bar Influence of azimuthal orientation on bar angle with the shell PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 30/32 FIGURE 10 Drop on bar with attack of door edge PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 31/32 FIGURE 11 Drop on bar Wall / bar and shell / bar angles for both configurations PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
A N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE 32/32 FIGURE 12 Drop on bar Shear energy on hinges PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
Appendix 1 A Appendix 1 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A1 - 1/2 Calculation of loads on the door connections 1 - Uniform lateral loading The uniform lateral loading corresponds to the assembly mass and to the deadweight of the vertical portion of the door.
Reactions at the supports:
x VA = -VC = - ql/16 FRAMATOME ANP - Nuclear Fuel - Design and Sales Division x HA = - 7ql/16 x HC = 9ql/16
- *~ ' i A
! Vt\
2 - Spot loading The spot loading corresponds to the mass of the horizontal portion of the door.
Reactions at the supports:
x VA = -VC = 0 x HA = 0 x HC = P J
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A Appendix 1 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A1 - 2/2 17x17XL 16x16
+ 24 rods and 18x18 UO2 linear mass (kg/mm) 1111 l l 1111 l l door length (mm) 1111 l l 1111 l l Mass of a door (kg) 1111 l l 1111 l l Linear mass of a 1/2 door (kg/mm) 1111 l l 1111 l l Length loading a hinge pin (mm) 1111 l l 1111 l l Uniform load: ql (daN) 1111 l l 1111 l l FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Spot load: P (daN) 1111 l l 1111 l l Lower vertical reaction: Va (daN) 1111 l l 1111 l l Upper vertical reaction: Vc (daN) 1111 l l 1111 l l Lower horizontal reaction: Ha (daN) 1111 l l 1111 l l Upper horizontal reaction: Hc (daN) 1111 l l 1111 l l Lower resultant: Ra (daN) 1111 l l 1111 l l Upper resultant: Rc (daN) 1111 l l 1111 l l 1111l g (daN)
Lower resultant at l 1111 l l 1111 l l Upper resultant at 1111 l l g (daN) 1111 l l 1111 l l hinge pin dia (mm) 1111 l l 1111 l l max stress in a hinge pin (MPa) 1111 l l 1111 l l Permissible limit for the hinge pins (MPa) 1111 l l 1111 l l Security coeff for the hinge pins 1111 l l 1111 l l Permissible limit for the locking pins (daN) 1111 l l 1111 l l Security coeff for the locking pins 1111 l l 1111 l l TF 018 Rév. 1
Appendix 2 A Appendix 2 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A2 - 1/1 Influence of the drop height between a 16x16 and a 17x17XL assembly Conventions:
x M16: mass of the internal equipment of a 16x16 assembly x Meq: mass of the internal equipment of a 16x16 equivalent assembly in a 17x17 internal equipment concept x h16: distance between bar face and internal equipment in a 16x16 assembly x h17: distance between bar face and internal equipment in a 17x17XL assembly Given: M16 = Meq + 'm h16 = h17 - 'h FRAMATOME ANP - Nuclear Fuel - Design and Sales Division To compare the 16x16 and 17x17XL arrays during drop on bar, we find the equivalent mass Meq of a loaded 17x17 internal equipment which will give the same perforating energy as a 16x16 internal equipment set dropped from a height l 1111 l mm less due to the larger section of the 16x16 assembly.
We have: E = M16 h16 g = Meq h17 g Or, replacing M16 and h16:
M16 (h17 - 'h) = (Meq + 'm) h17 Hence: 'm = M16 ('h/h17)
-Data:
x M16 = l l kg x 'h = l l mm x h17 = l l mm So we have 'm = l 1111l kg To compare the drop on bar for 16x16 with the one for 17x17XL, about l 1111l kg have to be taken off the mass of the internal equipment loaded with 2 16x16 assemblies.
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Appendix 3 A Appendix 3 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A3 - 1/2 Calculation of the incidence of an oblique drop on the shock absorber indentation PROPRIETARY PICTURE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Figure 1: straight indentation Given, S = l 1111l x 1111 l l = 1111 l l mm² PROPRIETARY PICTURE Figure 2: oblique indentation Let LT and lT the base and height of the triangle S1 Thus:
x LT = l l x lT = l l x h=l l x S1 = l l x S2 = l l x L=l l mm The crushed section is therefore l 1111l = 1111 l l + 1111 l l Table 1 gives the indented sections for varying angles and indentations; these sections must be compared with S (vertical drop without inclination) to obtain the indentation corresponding to the inclined drop.
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A Appendix 3 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A3 - 2/2 Table 1 Shock absorber deformation in an oblique drop PROPRIETARY TABLE FRAMATOME ANP - Nuclear Fuel - Design and Sales Division TF 018 Rév. 1
Appendix 4 A Appendix 4 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A4 - 1/1 Comparison between shells of thickness 1111 l l mm and 1111 l l mm 1 - Perforation energy The energy needed to perforate a l l mm thick steel plate with a bar l 1111 l mm in diameter using a zero drop angle is estimated to be l l KJ - ref. [5]. [5]. The inclination given to the assembly leads to a different bar angle of attack on the shell. The calculation of the equivalent rod diameter, which is a function of this angle, makes it possible to estimate the shell perforation energy for the two drop configurations.
For the first drop configuration, the bar / shell impact angle of l l ° induces an equivalent bar 1111 diameter of l l mm.
For the second drop configuration, the bar / shell impact angle of l l ° induces an equivalent bar 1111 diameter of l l mm.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Eperforation1 - l 1111l mm =l1111l = 1111 l l Joules Eperforation2 - 1111 l l mm = 1111 l l = 1111 l l Joules Eperforation1 - 1111 l l mm = 1111 l l = 1111 l l Joules Eperforation2 - 1111 l l mm = 1111 l l = 1111 l l Joules 2 - Kinetic energy Shell thickness of l1111l Shell thickness of l 1111l mm mm Shell without reinforcement 1111 l l kg 1111 l l kg Others 1111 l l kg 1111 l l kg Total 1111 l l kg 1111 l l kg Ekinetic l 1111l mm =m.g.h=l 1111l = 1111 l l KJ Ekinetic 1111 l l mm l l = 1111
= 1111 l l KJ 3 - Impact energy Eimpact= Ekinetic - Eperforation Eimpact1 - l 1111l 1111l KJ
=l > Eimpact1 - l 1111l =l1111l KJ mm mm Eimpact2 - 1111 l l mm = 1111 l l KJ > Eimpact2 - 1111 l l mm = 1111 l l KJ The impact energies of the bar on the door in the case of a plate thickness of l l mm are greater than those obtained for a shell thickness of l l mm. 1111 TF 018 Rév. 1
Appendix 5 A Appendix 5 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A5 - 1/1 Influence of longitudinal incidence for drops on bar 1 - Angle of impact between the shell and the bar The calculation of the angle made by the bar axis with the normal to the wall is detailed in [11]. This calculation is made by rotation of the marks IXYZ (drop N°1 with I being the bars point of impact with the shell) and GXYZ (drop N°2 with G being the centre of gravity of the packaging) on their respective origin, with longitudinal incidence and azimuthal orientation as parameters.
By determining the angles for the above two drop configurations, it is possible to locate the bars point of impact on the shell.
The normal to the shell, angle T, consists of the straight line (dashes on diagram 1) of which one point lies on the geometrical axis of the cylinder formed by the shell and the other by the bars point of impact on the shell. Consequently, the angle between the shell and the bar is the angle that this normal FRAMATOME ANP - Nuclear Fuel - Design and Sales Division to the shell makes with the angle between the door wall and the bar, i.e. J.
Assuming a mark whose x axis coincides with the normal to the shell, a change of mark by successive rotations about angle T, E and D makes it possible to easily determine the angle between the shell and bar according to the formula (§ 4 [11]):
J = Arc cos [ cos D . cos ( E - T ) ]
For both drop on bar configurations, the curves in Figure 10 give the angles of impact between the door wall and the bar, and between the shell and the bar. The angles obtained make it possible to determine the shell perforation energies by means of equivalent bar diameter calculations (Figure 4).
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Appendix 6 A Appendix 6 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A6 - 1/2 Comparison between 16x16-18x18 and 17x17 arrays for flat drop 1 - Computation of the overall bowing 1.1 - Internal equipment bowing Bow of a beam on two supports under a uniform load: fmax = - l 1111l.w.l / 1111 4
l l.E.I where w = m.J / l The respective dimensions of the frame and doors are extended by the same distance, so we can consider that the internal equipment inertia is proportional to h4.
1111l = 1111 In these conditions, f16/f17 = l l l = 1111 l l
Conclusion:
the bowing of the internal equipment in 16x16 and 18x18 arrays is smaller than for the FRAMATOME ANP - Nuclear Fuel - Design and Sales Division 17x17 arrays.
1.2 - Internal equipment impact velocity Assuming initially that the internal equipment is infinitely rigid, the whole of the incident drop energy will be transmitted to the frame rotation during the first impact.
E = mgh = 1/2.J.w² where J = 1/3.m.l² (rotation of a bar relative to its end).
The rotation velocity is independent of the mass since w = (6gh / l²) 0.5.
The maximum theoretical velocity of the internal equipment should therefore be about l 1111l m/s but the first impact with the ground causes bending of this system.
The actual velocity will be maximum when the second impact coincides with the counter-bending of the internal equipment.
A more rigid internal equipment will lead to smaller bending and counter-bending. The velocity of the second impact will be smaller.
Conclusion:
the second impact velocity of the internal equipment in the 16x16 and 18x18 arrays will be smaller than for the 17x17 arrays, therefore less demanding for the internal equipment.
2 - Computation of the local bowing The internal equipment of the 17x17 container undergoes a peak bowing during its flat drop, assessed at l l mm. A l l mm conservative peak bowing value is considered for the 18x18 container (bounding value as the peak for the 17x17 internal equipment is higher than the 18x18 peak value (cf.1.1.).
This peak bowing corresponds to a maximum rotation angle between two succesive door ribs equal to 1111 l l rad.
This induces a maximum longitudinal warping Gm = l 1111l mm for the door section.
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A Appendix 6 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A6 - 2/2 2.1 - Risk of local door buckling The maximum compression stress Vm for a door section is given by:
Vm = EH = E x (Gm /Lm) where Lm: maximum distance between two door ribs.
Lm = l1111l mm for 18x18 container.
and E the elasticity modulus for the container.
FRAMATOME ANP - Nuclear Fuel - Design and Sales Division Eulers critical load Vc is given by Vc = 32 x E x I / (S x Lm2)
I: smaller moment of inertia of the door section, I = l 1111l x 106 mm4 or so S: door section equals l 1111l mm 2 or so 2
Comparing Vm and Vc is the same as comparing Gm and 3 x I / (S x Lm).
2 We have 3 x I / (S x Lm) = l 1111l mm and 1111l mm, it is possible to confirm that V Gm = l m < Vc.
Therefore, the local buckling of a door section is not conceivable.
2.2 - Risk of local buckling of the door section upper core Let us now consider the upper core of the door.
1111l mm and the smaller inertia moment I = 1111 In this case, the section = l 2 l l mm or so. 4 2
We have 3 x I / (S x Lm ) = 1111 l l mm and G = 1111 l l mm.
m Thus we can conclude that Vm < Vc and local buckling of the upper core of the door is impossible.
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Appendix 7 A Appendix 7 N° TFXE DC 2104 E0 FRAMATOME ANP REV. E PAGE A7 - 1/1 Impact of the17x17 XLR guiding pins on the vertical drop Buckling force of the pins OD 1111 l l Number 1111 l l L (mm) 1111 l l S (mm²) 1111 l l I (mm4) 1111 l l K 1111 l l FRAMATOME ANP - Nuclear Fuel - Design and Sales Division E (daN/mm²) 1111 l l P = 2.K.S².E.I/L² 1111 l l daN Reaction force on the top supports The crushing of the internal equipment on the axial shock absorber induces an overall deceleration of l 1111 l g. This deceleration leads to a loading on the top supports of 1111 l 1111 1111 l g x l l daN or l l daN.
In view of this result, the buckling of the pins will have only a very slight impact on the assembly damage.
l l daN l l daN I
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