ML20148A879
| ML20148A879 | |
| Person / Time | |
|---|---|
| Site: | 07106058 |
| Issue date: | 04/21/1979 |
| From: | Burian R Battelle Memorial Institute, COLUMBUS LABORATORIES |
| To: | Macdonald C NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| 12549, NUDOCS 7905100126 | |
| Download: ML20148A879 (42) | |
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April 12, 1979 IU Mr. Charles E. MacDonald, Chief U.S. Nuclear Regulatory Commisnion Transportation Branch Division of Fuel Cycle and Material Saf ety Was hin g to n, D.C.
20555
Dear Chuck:
Enclosed are eight (8) copien each of the " Revision A Amendment to Safety Analysis for Shipment of Radioactive Waste Materials in the ':odified NECO Shipping Cask Model B3-1", and the overall assembly drawing for this cask (Battelle Drawing No. 9958-8501-0001, Rev. Q.
The Amendment is being sub-mitted on behalf of the Union Carbide Corporation, Tuxedo, Neu York.
Mr.
Marcus H. Voth of Union Carbide is sending you a letter requesting your review of this amendment and the granting of a certificate of compliance for use of two B3 casks having the changes indicated in this Amendment.
In letters to you dated March 12, 1979, and March 22, 1979, Mr, Voth described deviations in the configuration and materials in the two B3-1 casks recently obtained by Union Carbide. At Mr. Voth'a request, Battelle's Columbus
- 1. abo ra t o r ier has reviewed the devia tions and made recommendations for corrective act on.
The Amendment A Revision to the Safety Analysis Report (S/1RP) show., that the casks, as corrected, meet the regulatory requirements for all shipnents for which this cask was previously certified.
The introductory pages to the Amendment describe the deviations, the corrective action to be taken, and the portions of the SARP which are af fected.
The Amendment is in the normal
- format, i.e., replacement pages wit h the chan;.,ed pages having a revision indication at the botton.
Where only part o f a page is chonged, that part is indicated by a vertical bar in the cargin.
ne at 'it. 976-7502.
Any questions regarding the SARP can he directed to Other questions should be directed to Mr. Vo t h a t (9]4) 351-2111, Ext. 345.
Sincerely,
)
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N; s GW l
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Richard J.
Curian
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Research Engineer
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Nuclear and flow Systens Section USNRC p?\\
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Revision A Amendment jp}11 Safety Analysis for Shipment of Radioactive Waste Materials in the Modified NECO Shipping Cask 4
Model No. B3-1
\\
Reference Documents (1)
Safety Analysis Report for the Shipment of Radioactive Waste Materials in the Modified NECO Shipping Cask Model No. B3-1, Battelle Memorial Institute, Columbus Laboratories, March 14, 1969.
(2)
Battelle Design Drawing No. 9958-8501-0001, Revision B.
1
( 3)
Battelle Design Drawing No. 9958-8501-0001, Revision C (as built).
I
_ Introduction 3
This amendment to the safety analysis of the design and proposed j
uses of the modified NECO Model B3-1 applies specifically to casks of this style owned by Union Carbide Corporation, Tuxedo, New York, and having the i
following identifying numbers:
PPI Part No. D35136-1-02 and PPI Part No.
I D35136-1-03.
These casks were constructed from materials other than those j
specified in Enttelle Design Drawing Reference 2.
In addition, the outer shell laminate (fire shell) was omitted f rom the side, cover and bottom. This 3
nmendment describes the corrective action taken by Union Carbide to rectify the deviations.
The results of analyses are presented to show that these corrections and the use of alternate materials is acceptable and that the safe operation of the cask through all specified normal and accident conditions is a ss ure d.
Battelle Design Drawing No. 9958-8501-0001, Revision C forms part of this amendment, f
The as built cask, corrected to rectify the deviations in config-uration, is shown in Reference 3.
This drawint; indicates that the cask with the corrections has the same configuration as the original design REV. A, APR. 9, 1979 3/e$&
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Drawing Reference 2, with three exceptions:
(1)
The lugs. penetrate the 1-inch thick doubler plate at the top of the cask and are welded to the 1/2-inch thick outer shell (2)
The drain plug boss penetrates the 1/4-inch thick fire shell laminate and is welded to the 1/2-inch thick outer shell (3)
The materials of construction are all Type 304 stainless steel and the weld metal is Type 309L
-stainless steel weld filler.
In this configuration, the thermal, shielding, and criticality evaluations presented in Reference 1 are valid.
In addition, some of the structural evaluations presented in Reference 1 also are valid.
Those structural considerations which are no longer valid due to either the configuration of the lug and drain boss attachment or due to the use of stainless steel are re-evaluated below.
In order to facilitate review of the analysis the entire Description of Cask Section and the Structural Integrity Analysis Section from Reference 1 are reproduced with the appropriate changes.
- Analyses, or wording which has been changed are indicated by a vertical bar in the right margin and identification "Rev. A, April 9, 1979", in the bottom margin of that page.
11 REV. A, APR. 9, 1979 m
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, erw <
s' Revision A Amendment to SAFETY ANALYSIS s
for THE SilIPMENT OF RADI0 ACTIVE WASTE MATERIALS IN Tile MODIFIED tiECO SHIPPING CASK MODEL NO. B3-1 1
from
)
i l
J BATTELLE MEMORIAL INSTITUTE Columbus Laboratories April9, 1979 i
i l
_ INTRODUCTION 4
l This report presents a safety analysis of the des ~ign and proposed uses of the modified NECO Model No. B3-1 shipping cask for transporting i
large quantities of Fissile Class II radioactive materials to and from j
various sites at which assorted nuclear wastes are handled.
Normal shipments of the radioactive materials are to be made by sole-use truck-trailer according to commercial conditions and regulations, i
4 l
SUbDWRY' i
i f
A safety evaluation has been made of the modified NECO Model B3-1 j
shipping cask (package) it accordance with { 71.23 of 10-CFR-Part 71.
The results of the evaluation ndicate that:
4 (a) The package satisfies the standards specified in l
Subpart C of 10-CFR-Part 71; and (b)
Five (5) similar packages (Fissile Class II) may be transported together in accordance with
{ 71.39 of 10-CFR-Part 71.
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REV. A, APR. 9, 1979 y.-
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i 2
PACKAGE DESCRIPTION 1
)
Description of Cask I
i i
Cask Design Drawing No. 9958-8501-0001, Revision C, accompanying the Safety Analysis Report presents the configuration of the modified NECO Model B3-1 shipping cask.
The modified cask has a calculated empty weight of 20,500 lb.
The total 2nvelope dimensions are 51.50 in, in diameter x j
61.50 in. high.
l The basic cash body is 41.00 in. in diameter x 57.00 in, high.
i it consists of two concentric stainless steel shells which form an annular i
region which is filled with chemical lead.
The outer shell is of a laminated steel cons truction.
The innermost layer of the two laminates
\\
is made of 1/2-in, stainless steel plate.
The 1/4-in. outer layer of the i
laminated outer shell covers the bottom of the cask and the cylindrical i
l sides to within 12 in, of the top.
The upper 12 in, of the outer latninate layer is comprised of a 1-in.-thick band of stainless steel.
The outer laminate layer is made of one, two, or three sections joined by longitudinal seam welds.
The laminate is welded to the inner layer at the corners of the cask and at the point of intersection between the 1/4-in.-thick and 1-in.-
thick outer laminate on the sides.
The inner shell is made of 1/2-in.-thick stainless steel plate and is unchanged from the original design. With the cover in place, the internal cavity dimensions are 26.50 in, in diameter x 43.00 in. long.
The cover fits into a recess in the cask body formed by stepping the REV. A, APR. 9, 1979
=
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j 3
internal cavity diameter to about 32 in.
This recess is about 6.5 in.
deep and has tapering sides.
The top of the cask body is made of 1/2-in.-thick stainless steel plate welded to the inner and outer ehells.
Lead shielding consists of a 6-in. annulus on the sides and 6-in, slab sect: ions on the bottom and top (cover).
A liquid drain line penetrates the inner cavity at about the l
center of the cavity bottom.
The drain line termina tes in the side of the shell abant 3.25 in. f rom the bottom.
A double pipe plug affords a closure of this drain.
The closure is protected from mechanical damage by n 4-in.-diaccter x l-in.-thick stainless steel plate welded around the terminal hole of the drain line.
A lead safety plug is welded in the side o f the cast; about 4 in. from the bottom.
The outer and inner laminates of the outer shell are welded together to the drain line boss and sa f et y plug acsembly in the outer shell.
Six Lugs, equally spaced, penetrate the 12-in. -wide x l-in.-
thich outer laminate band at the top of the cask and are welded to both the 1/2-in, t hick outer shell and the laminate band.
These lugs provide bo th a means for Jl' ting the cask and tying it down to a vehicle.
The luga are nominally 5.50 in. high x 5.25 in. long x 1.5 in. thick.
They have an elliptical hoje 2.5 in. long x 1.5 in, wide cut i-h lug.
uie top of the lug is positioned 2.50 in, from the top of the cask. Attachment to the cask body is accomplished with full penetration welds.
Twelve bosses, made of stainless steel, are welded in the top of the cask so that the top of the boss is flush with the top of the cask.
I Each boss is tapped to accommodate 1-1/4-in.-7 x 2-3n. long used to secure the cover to the cask body.
The bolts are of the ASTM
)
i REV. A, APR. 9, 1979
s 4
A325 high-strength type. A tapered surface is machined on the circular edge at the joint between the inner cavity.shell and the top plate of the cask. This surface is the seat for the 0-ring used to provide i
secondary containment of the cask contents.
The cover of the cask is nominally 32 in. in diameter x 7.25 in, thick.
The sides are' tapered to fit the recess in the cask body.
The sides and bottom of the cover are made of 1/2-in. stainless steel plate.
The top plate of the cover is laminated.
The inner layer is 1/2-in.-
thick stainless steel and the outer layer is 1/4-in.-thick stainless steel. The 1/4 -in. layer is cut out around penetrations through the top plate including the bolt holes, a lif ting eye, and c safety plug.
The two layers cre welded together at the edges and around all penetrations.
Lif ting of the cover is provided by a U-shaped eye made of 3/4-in.-
diameter steel bar.
It is approximately 3.75 in, high and has an internal opening width of about 2.5 in.
The chemical lead-filled section between the top and bottom plates of the cover is 6.0 in. thick.
There are no materials in the cask which are specifically designed or used as nonfissile neutron absorbers or moderators.
Neither is the cask provided with any internal or external str.uctures or pro-tecting receptacles except as discussed above. All heat rejection is accomplished by conduction thrcugh the cask walls and radiation and convection from the cylindrical walls of the cask.
The cask is designed to opera te d ry, i.e., gaseous air is the only heat-transfer medium from the contents to the inner cavity wall of the cask.
R E V. A, A P R. 9,19 7 9
e 5
1
' Description of Cask Contents In accordance with the requirements of { 71.22(b) of 10-CFR Subpart B, the materials planned for shipment in the NECO Model No. B3-1 cask are described as follows:
f1) Radioactive Constituents - Identification and Maximum Radioactivity The radioactive contents of the cask include any radionuclide(s) classified according to the transport grouping in Appendix C of 10-CFR-71.
Quantities (in curies) of the respective radionuclides will be equal to or less than any one of the following group limits:
Transport Group Quantity (in curies) 100 I
590 II III Cencial.
800 Co-60 28,000 Cs-13'l 80,000 1,430 IV 12,000 V
VI and VII.
100,000 1
_(2) Identification and Maximum Quantities of Fissile Constituents Fissile constituents planned for shipment in the cask along with respective quantities are as follows:
U-233 200 grams Pt-239.
200 grams U-235 350 grams
- As defined in { 173.390 of 49 CFR and Appendix C of 10-CFR-71.
B
~
6 (3) Chemical and Physical Form The chemical and physical form of the package contents cannot
)
be explicitly defined since the latter will be primarily radioactive wastes.
_(4 ) Extent of Re flection, Meutron Absorbers, and H/X Atomic Ratios Ecficction, absorption, and atomic characteristics of the package contents are summarized as follows:
Extent of Reflection Maximum Reflection Honfissile Neutron Absorbers.
None Assumed (although various Present types would be present)
Atomic Ratio of Moderator to Fissile Constituents:
1sotope H/X U-233 450 Pu-239 800 U-235 500
.(5) Maxircum Weicht The maximum wcight of the package contents is 9500 lb based on e density equivalent to that of lead.
.(6) Maximum Amount of Decay Heat A decay heat load of 400 watts is the maximum analyzed for the package contents although subsequent calculations indicate that this value could safely be extended to 750 watts.
4
..... _ =..
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4 i
7 Structural Integrity Analysis i
j The structural integrity analysis of the modified NECO Model i
B3-1 shipping casks, ID Nos. PPI Part No. D35136-1-02 and PPI Part No, I
D35136-1-03 was performed to show compliance with the applicable structural i
I s
i requirements designated in the Code of Federal Regulations,10-CFR-Part 71.
Basically the casks consist of AISI Type 304 stainless steel plates and shells. The geometry is as presented in Battelle Drawing No. 9958-8501-0001, J
Revision C.
The structural components of the cask are made of AISI Type i
304 stainless steel and Type 309L stainless steel weld filler.
A.11 materials have been certified to their composition and properties.
(The 1/4-inch plate which has been ordered to be used for the I
laminate (fire shell) was ordered to specifications of minimum structural properties.)
In cases where some properties (such as bearing strength) l were not speelfied in the material certifications, these properties were obtained f rom the Aerospace S tructural Metals Handbook
- and MIL-HDBK-5A**.
In cases where property data were not specified, the values were estimated by referring to properties of similar materials.
The ASTM A325 bolts specified i
in the cask design correspond to Type 4 fasteners included in MIL-HDBR-SA.
.i The surface temperature of the cask was taken as 130 F, (from thermal analyses) and all structural material properties were degraded accordingly by the use of data presented in MIL-HDBK-5A, Table 1 summarizes the properties of the materials utilized in the design.
'~
Aerospace Structural Metals Handbook, Fourth Revision, Vol.
I, Ferrous Alloys, Code 1101, March, 1967.
- Metallic Materials and Elements for Aerospace Vehicle Structures, MIL-HDBK-SA, Change Notice 2, Sections 2.2.and 8,1, July 24, 1967.
l i
REV. A, APR. 9, 1979
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8 TABLE 1.
MATERIAL PROPERTIES UTILIZED IN NECO MODEL NO. B3-1 CASK DESIGN
.. =
Material Property Value, psi (
AISI Type 304 J
1/4-and 1/2-in. plate Tensile yield stress 37,300 Tensile ultimate stress 81,400 Shear ultimate stress 54,300 plate ( )
Tensile yield s tress 34,000 1-in.
Tensile ultimate stress 78,000 1-1/2-in. plate (b) rensile yield stress 31,900 Tensile ultimate stress 74,100 i
Shear yield stress 21,300 I
Bearing s tress 48,000 3/4-in, round(b)
,rensile yield stress 66,000 Shear yield stress 44,000 AWS 308L/309L Weld Filler ( }
Tensile yield 31,000 Tensile ultimate 72,000 Shear yield 20,700 i
Shear ultimate 48,000 ASTM-A325 bolts (d)
Tensile ultimate stress 120,000 (Type 4 fas teners)
Shear ultimate atress 89,000 (a)
A t. 130 F, (b) Material certification.
(c) AWS Specifications.
(d)
ASTM Specification.
i i
j REV. A, APR. 9, 1979
. ~, -.. - - - -, - - ~....,
i 9
Genertl Standa rds (? 71.31 of 10-CFR-71) i 1
a.
No Internal Reactions.
The materials used--steel ar.d lead, 1
l do not react with each other in such a way as to cause deleterious amounts of corrosion products.
b.
Positive Closure.
Closure of the cask is accomplished by 12 ASTM Type A325 bolts.
These bolts provide positive closure of the cask during normal shipping conditions. The closure with respect to accident conditions is analyzed in a subsequent section.
c.
Lifting Devices.
l col.
Support Three Times the Loaded Height. The cask is provided with six lugs equally spaced. These devices afford a means of tiedown as well as lifting of the cask.
For purposes of analysis, it j
is assumed that only two of the six lugs will be used at any one time for lifting the loaded cash.
Therefore, the total load per lug is:
W 3
P = 3 X y = 7(30,000) = 45,000 lb,
I It is further assumed that a 1-1/2-in. clevis pin will be used to engage the lug, When used as a lifting device, the lug can fail in any one of five modes; the analyses for these failure modes are presented below.
c.1.1.
Shear in the Lug Wolds. The shear stress in the welds between the lug and the cask shell is:
L 45,000 45,000 Ush " lI " 2(0.707)(0.75)(5.5) " 5.84 E8 t
..c w~.
.m. - - -
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10
?
The marnin of safety is calculated to be:
"Y -1 = 20,700 -1 = 1.68.
MS =
l 0
7,700 3h c.1.2.
Fiber Failure in the Lug Weld at the Cask Shell. The fiber stress in the weld is produced by the moment of the vertical load on the lug and is represented by:
Mc g,
f ITop where ITop " I + Ad
=2
+ (bh)( )
o
(_0. 707 ) (0. 7 5 ) (5. 5 )
+ (0.707)(0.75)(5.5) - = 58.7 in.4
'2 12 4
l M = (P )(c) = (45,000)(2) = 90,000 in.-lb l
c = h = 5.5 in.
~
The fiber stress is, the re fore :
(90,000)(5.5)
= 8400 psi f
58.7 The margin of safety 13 ty 31.000 Ms =
,1
-1 = 2. 69 i
o 8,400 g
]
f REV. A, A PR. 9 1979
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c.1.3.
Shear Throuch the Eye of the Lug.
The shear stress developed in the eye by the clevis is:
L 45,000
. 45,000 = 6900 psi Ush " T " (1.5)(2.25 + 2.12) " 6.55 The margin of safety is:
F MS =
-1 =
-1 = 2,08 q
900 I
c.1.4.
Tensile Failure of the Eye of the Lug.
The minimum area of the lug in tension is that corresponding to. a horizontal plane through the eye which is:
A = t (W - d) = 1. 5 (4. 25 - 1.5 ) = 4.12 5 in. 2 The corresponding stress is:
IL 45.000 t " T
- 4.125
,900 psi,
a
=
and the cargin of safety is:
F
-1=f'900 -1 = 1,92.
MS = q c.1.5.
Bearinn in the Eye of the Lug.
The area for bearing of the clevis pin in the eye of the lug is the projected area of the clevis pin on.the car of the lug; therefore, the bearing stress is:
45,000 "br (1.5)(1.5) = 0,000 psi REV. A, A PR. 9 1979 __
7
12 The margin of safety is:
l F
l MS =
-1 =
- 1 = 1. 4.
br c.7.
Support Three Times Weicht of the Ltd. A singic U-' shaped eye is provided for lif ting the cover of the cask.
Material properties of the c'e and the weld which 'ecures the eye to the cover y
s of the cask were considered to be those of ISI 1025 steel. The 51'ftingdevice (U-shaped eye) can fail by any one of three modes; analyses corresponding to each of these modes are presented below.
c.2.1.
Tensile Failur'e of the U-Eye.
The load is assumed equally supported by both legs of the U-eye.
The re fore, for a total cover weight 2260 lb, the load on each leg is:
= 3(f) = f(2260) = 3390 lb.
P The area recisting this load is:
2 2
'(n)(0.751 = 0.441 in.2 A = nD 4-u 4
REV. A, APR. 9,1979
13 l
~
and the stress is:
PL 3390 i
t A
0.441 = 7700 psi a = - - =
1, Thus, the margin of safety is:
1 i
F 4
ty -1 = 66,000 -1 = Larna.
MS =
,,,99 t
c.2.2.
Shear Failure of the U Shaped Eye.
Shear stresses will develop in the U-shaped eye due to forces caused by crane hooks or similar mechanisms during lifting of the cover.
Fur th ermore,
the maximum shear r, tress will occur at the top of the U-shaped eye where i
the cross-sectional area resisting the shearing force is a minimum.
Accordingly, the maximum shear stress is:
PL o
=
sh A
min khere as above, P
= 3390 lb and A
= 0.441 in. 2 min Therefore, 3390
= 7700 psi o
=
sh 0.441 and the mdtgin of safety is:
F"Y -1=Of'00h-1=Large.
MS =
sh R E'V. A, A. P R. 9,19 7 9
s 14
~
c.2.3.
Shear in the t,' eld Be tueen the U Shaped Eve and the Cover. The shear load in each weld is P, whereas the area subjected to the shear load is:
A = nd(0.707)(t).
If the diameter is conservatively taken as the diameter of the U-shaped eye and the weld thickness as the thickness of the top plate of the cover, the resulting area is:
A = (n)(0.75)(0.707)(0.5) = 0.833 in.
and the corresponding stress is:
sh "
"083 = 6070 psi.
Thus, the margin of safety is:
F I
MS =
-1 = 2
-1 = Large, c.3.
Nonlifting Attachments Covered or Locked. The U-shaped eye on the cover and the cover closure are not designed to permit its use as a cask-lifting device.
Therefore, a C-plate which bolts onto the eye is provided to prevent inadvertent use of the component as a cask-lif ting device.
The drain plug is recessed in the side wall of the cask.
This adequately protects it from damage by normal contact of the cask with other objects uhich might occur during bandling and transit.
9 REV. A, A PR. 9,1979
~.- - _.
15 c.4.
Failure of the Lif ting Device Would Not Impair Containment or Shiciding.
Impairment of containment or shiciding due to failure of the lif ting device would be less severe than in the case of the 30-ft drop which is considered in a subsequent section.
d.
Tiedown Devices.
d.1.
No Yiciding With 10G Longitudinal, SC Transverse t and 2G Vertical Forces. The six lugs provided for lifting the cask are also designed for tiedown of the cask to the bed of the transport vehicle.
For purposes of analysis, it was assumed that the cask was positioned on a bed 8 ft wide (a' common width of truck beds).
It was further assumed that i
the tiedown cables extend in a radial direction from the cask to the vehicle bed (see Figures 1 and 2).
The forces on the tiedown lugs were evaluated for two orientations of the cask on the vehicle bed.
In the first (Figure 1), the cask was posi-tioned so that the 10G longitudinal force through the center of gravity of the cask was directed through two opposite lugs (Numbers 1 and 4 in Figure 1).
In the second case (Figure 2), the cask was rotated 30 degrees with respect to the first case so that the 10G longitudinal force was directed midway between adjacent lugs.
It was assumed that those cables which are not attached to the sides of the bed (e.g., Cables 1 and 4 in Figure 1) make an angic of 45 degrees with the axis of the cask.
However, for those cables which are assumed to be at tached to ti e side of the bed, the ang1cs were calculated.
Cables 2, 3, 5, and 6 in Figure 1 form an angic of about 33 degrees, wherecs Cables -3 and 6 in Figure 2 form an angic of about 26.5 degrees.
5
16 h
3' 2
5"G l
8 f t.
4
(
.e s
IOG 2G
(
Vertical upward 6
5
' I__
FIGURE 1.
CASK ORIENTATION FOR CASE OF 10G LOAD PASSING TilROUGH TWO LUGS wa
}
3 4
2 a5G 8ft lbG 2G Vertical upward 5
6 4
a as FIGURE 2.
CASK ORIENTATION FOR CASE OF 100 LOAD PASSING IIDWAY BETUEEN ADJACE:T LUGS 4
-.__..,......y e
..m..,,.
l-l 17 i
The analysis of the forces on the lugs was performed assuming all three imposed G-forces to be acting simultaneously. Also, as is customary, it was assumed that the cask is adequately blocked at the base so that tipping rather than cliding, or sliding and tipping is impending.
Analytical results are presented in Tabic 2:
TABLE 2.
FORCES ON TIEDOWN LUGS FOR CASK ORIENTATION CASES 1 AND 2*
Force, Ib Lug No.
Case 1 Case 2 1
80,700 81,200 2
43,400 62,200 3
19,700 4
5 38,000 15,300 6
78,000 57,800 4
- Shown in Figures 1 and 2, respectively.
These data indicate that for Case 1 about 66 percent of the load is almost equally divided between the two lugs with the remainder being almost equally divided between two other lugs, leaving a nealigible force on the remaining two lugs.
In Case 2, about 86 percent of the iaad is applied to three lugs with the remaining load being shared by two other lugs.
The maximum load on one lug was found ta be for the Case 2 orientation, i.e., 81,200 lb.
This load was used in the following analyses -
of stresses in the lug when the latter was utilleed as a tiedown device.
6
....-----r mm
r 18 The lug can fail by any one of six modes. Analyses corre-sponding to each of these failure modes are presented below.
d.1.1.
Shear in the Weld Between the Lug and the Cask Shell. The shear in de welds between the car of the lug and the shell of the cask is:
F sh "
]
where F is the vertical component of the load on the lug. Then, F = (cosce)(F) = (0.707)(81,200) = 57,400 lb,
and A = 2(0.707)(t)(2) = (2)(0.707)(0.75)(5.5) = 5.84 in.2 which result in a stress of:
F 57 00 = 9800 psi o
=
=
g The corresponding cargin of safety is:
MS =
-1 =
01 l'13' sh
's d.1.2.
Fiber Failure in the Weld of the Luc to the Cask Shell.
The fiber stress is produced by the moment of the vertical and horizontal components of the load on the lug. Thus, M = (F )(e ) + (F )(e )
x M = (57,400)(2) + 57,400 (2.25) = 241,600 in.-lb,
4 REV.Ao A PR. 9J 979
i 19 and the stress is:
MC o =
f IBot where e = h = 5.5 in.
]
and 2
bh I
=I
+ Ad
=2
+ bh ( )
Bot o
_12 From Section c.1.2.,
I = 58.7 in.
Therefore, (241,600)(5.5) = 22,600 psi,
f 58.7 and the inargin of safety is:
p i
MS = -
-1 =
600 -I = 0. 37 d.1.3.
Shear ThrougF the Eye of the Luc.
The shear of the tiedown clevis through the eye of the lug is:
o
- g where F = 81,200 lb and A = 2 t d = 2 (1.5)(2.12) = 6.36 in.
Therefore, 81,200 o, = 6.36 E"
The margin of safety is:
Psy 21,300
-1 =
0.66,
-1 = 12,800 FG = c3 R E V. A, A P R. 9,19 7 9 --
/
20 d.1.4.
Tensil Failure of the Eye of the Lug.
The load on the lug tends to cause a tensile failure of the eye.
For a l
minimum stress area of:
A = (" ~
)t Co &2 where w = width of th; lug = 4.25 in.
d = width of the eye = 1.5 in.
a = angle of the area plane with the horizontal = 45 degrees l
t = thickness of the car = 1.5 in.
and A = 4. 2 5 - 1. 5 (1. 5 ) = 5. 84 in. 2.
0.707 The stress is:
F 81.200 t
- I
- 5.84
'9 P8 a
which results in a margin of safety of:
F l'
-1 1.29.
MS =
-1 = 1 90 y
d.1.5.
Bearine in the Eye of the Lug When the Luc is Used as a Tiedoun Device. The clevis imposes a pressure over a 135-degree arc of contact with the eye of the lug as shown in the sketch below, s
/
4--
d --*-
/
zr 135*-
4l A-V P
F REV. A, A PR. 9 1979 7
21 The bearing area is:
d l
A = t (1 + 0. 707 )7 = 1. 5 (1. 707 ) (1. 5 ) = 1. 9 2 in. 2 and the bearing stress is:
br 1.h
,300 psi,
which results in a margin of safety of:
F "Y -1=f,'2)"00
-l = 0.13.
MS =
br t
d.1.6.
Fiber Failure of the Cask Shell Ad jacent to the Lug. The lug was assumed to act as a trunnion imparting both a bending moment and a pull-out force ca the shell of the cask as shown in the sketch below:
pr 7A A
's I
- >- b Y
j_7 r
N
-b t
7 REV. A, APR. 9,1979
i 4
22 j
Also, the shell was conservatively assumed to be a flat plate 12 in. in diameter. 'The ef:..:. on the stresses in the shell by the applied loads was examined for both simply supported and fully fixed conditions at the edge of the 12-in.-diameter plate.
q Fcr the casc of the applied moment, the severest stress condi-l tion exists hen the edges of the plate are assumed to be simply supported.
i In accordance with Roark, Case 5, the stress is defined as:
3M f
~ 2 (A - r) ( r + 0. 7A{2 r " 4n t r 1 + (v + 1)1n 3
~
1 o
2 3
0.49 A 4
l The moment is:
]
M = (F )(c) = (57,400)(2) = 114,800 in.-lb,
and l
^
t = 1.5 in.
I 5.5 r=
= 2.75 in.
2 V = 0.3
)
A = 6 in.
Therefore, the maximum fiber stress is:
l c
= 14,700 psi g
For the case of the pull-out force, F, the worst stress condi-i tion exists when the edges of the 12-in.-diameter plate are assumed to be l
fully fixed. Accordingly, from Roark Case 20, the stress is defined as:
t.
4
- Roark, R.
J.,
Formulas for Stress and Strr n, Fourth Edition, McGraw-j 4
11117 Book Company, New York, Chapter 10, page 217, 1965.
- A Ibid., page 222.
1
23
)
i s
l
~
2A 2
3F 1-(in A) o =
j, 2nt A
-r r
4 where F
r-F = 57,400 lb,
X and the other dimensions are the same as above.
Therefore, the maximum 1
fiber stress is:
o
= 11,900 psi.
f The total maximum stress in the shell is the sum of these two stresses, i
That is, a
= 19,700 + 11,900 = 26,600 psi f
rM + d o
=o i
This stress occurs on the surface of the shell at the top of the lug.
The margin of safety is:
i F
ty 34,000 MS =
-1 = 26,600 -1 = 0. 28 o
f d.2.
Nontiedown Devices Covered. or Locked. The nontiedown devices will bn covered as describe'd above in Section c.3.
1 d 3.
Failure of the Tiedown Device Uould Not It*pa i r Meeting Other Requirements.
Failure of the tiedown device would not impair meeting other requirements of the cask as described above in Section c.4. and in the subsequent section on accident conditions.
~
4 REV. A, APR. 9,1979
4 24
\\
l i
Structural Standards for Large-Quanrity Packaging
(_9 71.32 of 10-CFR-71)
]
l a.
Load Resistance.
The requirement for load resistance is that, when siinply supported at its ends, the cask must be able to withstand a uniformly distributed load equal to five times the cask weight.
Conscr-vatively, the outer shell alone is assumed to support this load. Accordingly, the scress is:
- f "
where 1
1 6
M = g W L = (5)(g)(30,000)(57.5) = (1.08)(10 ) in.-lb D
41 e = 7 = 7 = 20.5 in.
4 4
d
-d o
i n
4 4
4 g
= g (41
- 39.5 ) = (1.94)(10 ) in,4 Ir n and the corresponding stress is:
6 f = 7 = -(1.08)(10 )(20.5) = 1140 psi,
Me o
4 (1.94) (10. )
which results in a margin of safety of:
F I
ty 0
MS =
_y,
~1
- 1##8 0
b_.
External Pressure.
The requirement for external pressure is that the cask must be able to withstand an external pcessure of 25 psig without loss of contents. The outer shell was conservatively assumed to withstand this pressure with no assistance from the lead in which case the shell could fail by stress failure of the end plates, stress failure of the cylindrical shell, or collapse of the outer shell.
These cases are analyzed individually below.
REV. A, A PR. 9,1979
3 i.,..'.j.
s f'
25 b.l.
Stress Failure'of End Plates.
The severest stress condition exists when the edges of the end plate are assumed to be simply supported. According to Reark*, Case 1, the tr2ximum stress in i
the end plate may be described as:
i 1
3 D
= 3 ({}2 P(3 + V) i 2
{
Uf i
where l
D = mean diameter = 40.25 t = 0.75 in.
1 p = 25 psig V = '.$.3.
= y (40.25)2 3
(25)(3 + 0.3) = 2300,
j o
f 0.75 3
and the corre sponditig margin of safety is:
i F
2
-- o
_-1 = 37,300 -1 = large.
ty i
MS =
2,300 f
b.2.
Stress Failure. c f Cylindrical Shell.
The stress in i
a the shell is given by Roark, Case 1, as:
~
=$
c hoop 2t t
I 1
- Ibid., page 216.
- Ibid.. Chapter 12, page 293.
i i
I R E V. A, A P R. 9,197 9
8 26 where the dimetisions are the same as above. There fore, the fiber stress is:
f " (25)(40.25) = 670 psi,
U (2)(0.75) and the margin of safety is:
Ftv 37,300 MS =
-1 =
- E
~
670 f
1 b.3.
Collapse of the cylindrical Shell.
The critical collapsing pressure of a shell is given by Roark, Case 1,,'s:
a 2t tv E
F 2
c D
1 + -f1 (f):
where 6
E = cis.stic modulus = 29 x 10
- pgi,
- f,2)f0.75) 37.300 P
150.25
= 320 psi (40.25)2 c
33,800
+
6 0.75 (29)(10 )
and the margin of safety is:
P 320 MS = c -1 =
-1 = 1arge.
p 25
- Ibid., Cha pt e r
,, age 298.
l REV. A, APR. 9,1979
27 i
i Evaluation of a Single Package ($ 71.34 of 10-CFR-71) a.
E f fec t of Transport Environment on Safety of Cask.
1 a.1.
Normal Transport Conditions (Appendix A of 10-CPR-71).
The structural requirements of the cask for normal transport conditions as specified in { 71.35 of 10-CFR-71 are less severe than those analyzed in previous sections as well as those analyzed in subsequent sections for accident conditions.
I a.2.
Accident Conditions (Appendix B of 10-CFR-711 n.2.1.
Thirty-Foot Free Drop onto a Flat Surface.
The first condition which the cask must withstand in the hypothetical acc dent scquence is a 30-f t: fall onto a flat, unyiciding surface.
There are three critical orientations which the cask can assume at the moment of impact. These include direct impact on an end, direct impact on the cylindrical side, and impact on an edge at such an angic that the reaction force is directed through the center of mass of the cask. These conditions are evaluated individually below.
1 a.2.1.1.
End Impact.
In the case of a direct end inpact, the force is evenly distributed over the end of the cask.
Furthe rmo re, the kinetic energy of the cask at the moment of impact must be absorbed by deformation of the cack shell and shielding material; this quantity is d _ fined as:
V3 = hU,
where h = the drop height = 30 ft = 360 in.
W = the loaded cask weight = 30,000 lb.
m
+,
3 28
. s 1
i i
The energy absorbed by the cask during deformation is:
E=Vk, i
whcre 4
j V = volume of material displaced, in.
t k = energy absorbed per unit volume, in.-lb/in.3 t
By equating the above equations, the volume of material displaced is j
j found to be:
V = hW t
k On the basis of data from tests conducted on casks and cask materials by 4
\\
OPML, it can be shown that a conservative value for the energy absorption o
')
of lead is:
~
4 k = 10,000 in.-lb/cu. in.
I 4
If energy absorption in the steel shell of the cask is conservatively i
negIccted, the volume of lead which must be deformed is:
I i
V = hW = f360)(30.000) = 1080 in.3 k
10,000 i
From geometrit considerations, the volume of lead deformed is:
4 h
2 V = nd 6,
3 t
4, i
where s
6 = the depth of deformed lead t
l d = the diameter of the lead shiciding = 39.5 in, t'
Therefore, 4V2 " (4)(1080) = 0.88 in.,
6=
2 i
nd ud I
and the thickness of Icad shiciding which remains is:
4 t
=tPb-6n 6.00 - 0.88 = 5.12 in.
t
4 c'
o' 29 i
i a.2.1.2.
Side Impact.
In the case of direct impact on the side, the volume of Icad deformed is:
4 2
d V = qp (0 - sine)2,
where 0 = the angle subtended by the deformed arca (see sketch below) f = the longitudinal length of the deformed lead section
= 55.5 in.
a 1
1
?
\\
i k
g Deformed lead Therefore, O - sine = 8V (81(1080)
= 0.100,
2 " (55.5)(39.5)2
\\
Id e
and 0 = 49.0 degrees.
The corresponding depth of the deformed Icad is:
Od 49 6 = (1 - coc7)7 = (1 - cos5-)(39.5) 2
= 1.75 i
,i i
t t
'. ; ' :i l
30 which results in a residual lead thickness of:
s t
=t
- 6 = 6 - 1.75 = 4.25 in.
g Pb The average impact force during deformation is:
E EK hW F
=7=6 ~ 6 7
and the equivalent "g" load is:
- = f f =
= 17 = 206 "g's" l
G
=
7 When applied to the cask cover, this g-load must be resisted in shear by l
the 12 cover bolts, the resultant stress of which is determined by:
(G ) (W }
7 e
U sh (A)(n) where W = weight of the cover = 2260 lb e
A = the effective area of each bolt = 0.6331 in.
n = number of bolts.
Therefore, (206)(2260)
(0.6331)(l'2y=61,300 psi.
sh The ultimate shear stress of the ASTM Type A325 bolcs specified is 89,000 psi; this value results in a margin of safety of:
F MS =
-1 = 89 000 -1 = 0.45.
su g
61 300 sh l
l l
l l
e
,1 31-a.2.1.3.
Edce Impact.
In the case of impact on an edge, the deformed lead may be represented as shown in the following sketch.
D t
a s
p.
/
g y'
O Accordingly, the volume of lead displaced is:
3 3
V=()
tanx(sin 0 sin 0 - Ocos0).
3 For the edge drop, o = 35.5 degrees,
and, by trial and error:
0 = 64. 8 de gre e s.
The depth of deformed lead, 6, measured along a line from the edge of the cash through the cask's center of gravity is:
6 = 6.83 in.
l Therefore, the thickness of Icad remaining between the edge of the inner cavity and the deformed surface is:
t = 1.54 in.
1 e
s.
t 32 i
'Also, the impact load in "g's" is:
h 360 G = 7 = 6.83 = S3 g.
7 If the cask were to impact on a top edge of the cask, the weight of the cover and contents would produce both shear and tensile stresses in the bolts.
Furthermore, if the combined weight of the cover and contents A
are assumed to act at the center of the bottom face of the cover as shown in the sketch below, the maximum load on the bolts can be evaluated.
O i
I 1
c W
L i
CG g
/
I t
c a W s
x N
a 4
0 The maximum tensile stress in the bolts will occur in the bolt farthest away from the point of impact, 0, and is evaluated by the following I
equation:
C=
(
)0 where D
M = [Uf )7 - (W )t ]G = UC (Dpos:r-t sina)
I c = 3(D + DEC)
I = E(I
+ Ad )
g u
- i t g
33 vhere W = the weight of the cover and contents = 11,760 lb i
G = the "g" impact load = 53 g D = the cask diameter = 41 in, l
c = the cover thickness = 10.5 in.
c D
the bolt circle diameter = 37.0 in.
BC I = area moment of inertia for one bolt about its own c
neutral axis = 0.0319 in.
A = the effective area of one bolt = 0.633 in.
d = the distance of each bolt from a horizontal axis through "0" c = 35.5 degrees.
Therefore, i
6 M = (8.00)(10 ) in.-lb c = 39.0 in.
I = 4490 in.4 _
and 6
= --- = - ) (10 ) (3 9. 0 )
Me (8
o 4416
= 69,500 psi The corresponding margin of safety is:
F MS =
-1 = 120,000 cu
-1 = 0.73.
o 69,500 t
In addition, the shear stress is:
n Wsiny (11,760) (s in 35. 5 )
"sh nA nA (12)(0.633) 47,400 psi
=
which results in a margin of safety of:
Fsu 89,000 MS =
-1 = 4 7,4 00 -1 = 0. 88.
sh 4
I u
r
(
34 a.2.2.
Puncture.
l a.2.2.1.
Fortv-Tnch Drop on Six-Inch Steel l
Cylinder.
Second in the sequence of hypothetical accident conditions to l
which the cask trust be subjected is the 40-in. drop onto a 6-in.-diameter cylinder. An empirical equation for the minimum steel shell thickness required for lead-filled casks has been developed by the Oak Ridge National Laboratory.
The equation has the form:
y )0.71 t = (p tu where t = minimum shell thickness, in.
W = weight of lead-lined cask, Ib 1:,u = ultitrate tensile strength, psi.
Thc re fcn e, the required shell thickness is:
y )0.71 (30,000 0.71 (p
t=
0.M in, r
=
78,000 tu
./
On the bacis of an outer shell thickness of 0.75, the present cask design is shown to ccmply with the regulutory puncture criteria, a.2.2.2.
Drop on Lifting Lun.
In the event of a drop on the lifti.ng lug, the cask shell could be penetrated by the lug. The aforementioned empirical equation developed by ORNL for 6-in.-
diameter penetrators is not applicabic to the rectangular-shaped lug.
)
- Nelms, H.
A., " Structural Analysis of Shipping Casks, Vol. 3, Effects of Jacket Physical Properties and Cervature on Puncture Resistance",
Oak Ridge Nat ional Laboratory, ORNI.-rM-1312, Vol. 3, June, 1968.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _ _ _ _ -REV. A, A PR 9,1979
- dc
(
35 For calculational purposes, it is assumed that the shell would fail by pure shear of the lug throu;;h the 1/2-in, shell. The contribution of the weld
]
l of the 1-in, doubler to the lug is conservatively neglected. Shear area in the i
shell is given t,y:
A = 2t(W + h) = (2)(0,5 )(1.5 + 5.50)
A = 7.0in.
and the force to cause shear f ailure is :
F = (Feu)(A) " (54,300)(7.0)
F = 380,100 lb.
i Furthermore, the maximum force required to cause compressive yielding in the lug is:
F=F A=F A,
cy ty where A = (U)(h)
F = { 31,5r00) (1. 5)(5.50) = 26 3,200 lb.
Hence, the lut; will yield in compression before it will penetrate the outer shell of the cash, a.2.2.3.
Drop on the Cover of the Cask.
A drop on the cover of the cask must be analyzed to determine if the U-shaped eye (lifting device) on the cover would penetrate the top plate.
Accordingly, the force requtred to cauce one weld to shear is calculated by:
F = (F )(A) = (F
)(n)(d)(t)(0.707),
g where 4
d = the U-cye diameter = 0.75 in, the weld thichness = 0.50 in.
t =
REV. A < APR. 9 1979 n
0 o,.f i
g 36 O
s Therefore,
?
F = (48,000 )(n)(0. 75)(0.5)(0. 707)
F=
40,000 lb.
In addition, however, the U-shaped eye could possibly fail by bending as illustrated in the sketch below.
F IF Af
+
e 4-The resisting moment M is developed to counteract the couple produced by the bending force F.
According'y, the fiber stress developed in the U-shaped eye is:
f,
E.
11C. = _ E. f $YD)(0 a
A I
A I
= F(-
1
)
wher 2
A = ud = 0.441 in,2 4
c = 1.625 in, c = d/2 = 0.375 in.
4 nd 0.01558 in.4 Ie g-n REV. A, A PR. 9,1979
ar g
37 c,
The re fore,
+(*
S) f = F( 0.441 -
0.01558 c
= F(- 2.26 1 39.15)
= + 36.89 F or - 41.41 F and
- f "f
F=
or
+ 36.89
- 41.41 1
I If the fibet design stress, c, is taken as the yield stress:
f 1
f'F
= l'
= 66,000 psi c
cy and 66.000 66,000 F=
^
or 41.41
+ 36.89
= 1800 1b or 1600 lb.
Therefore, the U-shaped eye will fail in bending before the veld will shear, a.2.2 4.
Drop on Lug and Drain Bass.
For a drop on the side in which the irnpact occurs on the lug and drain boss (i.e., one* of the six lugs will be aligned with the drain boss), the lug and boac would tend to puncture the shell. The case of the lug was analyzed above and found to jic1d before puncture would occur.
In the case of the boss, the puncture condition can be evaluated by referring to the basic derivation of the puncture equation by Nelms for the case of a drop onto a 6-in. -disme ter cylinder.
The general empirical equation is:
E l
F = 2.4 d.6 1.4 F tu
- Ibid.. Chapterr VI, VII, anJ VIII.
R E V. A, A P R. 9,19 7 9
k 4 s.. 8 g
38 4
where the kinetic c'nergy of the cask at the moment of E
r p
impact, in.-lb I
F
= the tensile ultimate strength of the 1/2-in, shell = 81,400 psi d = the diameter of the penetrator = 4 in, t = the minimum permissible shell thickness, in.
i i
I For a drop on the lug and boss, it is assumed that half of the kinetic
)
energy would be taken by each member.
Therefore, 1
= pJh = 1(.30,000)(40) = 600,000 in. -lb,
27 and 600,000 = (2.4)(4 6)(t1.4) 1 81,400 t=
0.46 in.
Since the shell is 0.50 in, thick, it will not puncture.
b.
Shipment May Be Evaluated Tocether With or Without Transport
_ Vehicle. All of the foregoing structural analyses have been based on a shipment without transport vehicle.
c.
Other Transport Conditions May Be Approved by the Comission.
Not applicable, s
12549 REV. A, A PR. 9,1979