ML19341A577
| ML19341A577 | |
| Person / Time | |
|---|---|
| Site: | 07109111 |
| Issue date: | 12/17/1980 |
| From: | NUCLEAR PACKAGING, INC. |
| To: | |
| Shared Package | |
| ML19341A576 | List: |
| References | |
| 18123, NUDOCS 8101270146 | |
| Download: ML19341A577 (5) | |
Text
.
Revicion 3 December 17, 1980 i
SAFETY ANALYSIS REPORT FOR l
i MODEL CN6-80 SHIELDED CASK TO i
t 10 CFR 71 TYPE "A" PACKAGING REQUIREMEh"TS Prepared by:
Nuclear Packaging, Inc.
815 South 28th Street 3
Tacoma, Washington 98409 (206) 572-7775 8101270l%
R; vision 3 Decemb2r 17, 1980 0.2 Package Description 0.2.1 Packaging 0.2.1.1 General Description The Model CN6-80 packaging is a reusable shipping package designed to protect radioactive material from normal conditions of transport.
0.2.1.2 Materials _of Construction, Dimensions & Fabricatingbethods General Arrangement drawings of the Model CN6-80 packaging are included in Appendix 1.10.1.
They show the overall dimensions as well as the material.
The cask body consists of a one inch (1-1/8" for casks fabricated 3.
after October 31, 1980) external steel shell and a 3/8 inch internal steel shell separated by a 4 inch lead shield between two shells.
The top and bottom ends of the cylindrical cask are constructed of a pair of stacked 4 inch steel plates.
The top serves as a removable cask lid and is secured to the cylindrical cask body by eight lh" studs.
A 29" secondary cask lid is located in the center of the primary lid and is secured to the primary lid by eight 1" studs.
All internal cask surfaces are lined with light gauge stainless steel to facilitate decontamination.
Lifting lugs and tiedowns are a structural part,;
the package.
0.2.1.3 Containment Vessel l
The CN6-80 cask serves as the containment vessel and its mechanical 0-2
R;vicion 3 Decembar 17, 1980 1.0 STRUCTURAL EVALUATION This Section identifies and describes the principal structural engineering design of the packaging, components, and systems important to safety in compliance with the performance re-quirements of 10 CFR 71.
1.1 Structural Design 1.1.1 Discussion The principal structural member of the Model CN6-80 package is the primary containment vessel or transport shield, as described in Section 0.2.1.
The above components are identified on the drawing as noted in Appendix 1.10.1.
A detailed discussion of the structural design and performance of these components will be provided below.
1.1.2 Design Criteria The shield top and bottom are constructed of two-four inch thick steel plates laminated together to provide a full 8 inches of solid steel.
Cylindrical side walls have an external skin of 1 inch' steel plate (1-1/8 " for casks fabricated after October 31, 3
1980) and an internal skin of 3/8 inch thick plate.
These two plates encase 4k inches of lead resulting in a total side wall thickness of 5 5/8 (5 3/4) inches.
l3 i
i j
1-1
Revision 3 1.2 waightn rnd Cnnter of Grnvity December 17, 1980 The weight of the cask and liner (or payload) will not exceed j
51,500 pounds.
The cask weight is approximately 44,000 pounds.
]
The center of gravity for the assembled package is located at the approximate geometric center of gravity.
1.3 Mechanical Properties of Materials The Model CN6-80 packaging uses an orter and inner shell fabri-cated of various thicknesses of low carbon hot rolled steel conforming to ASTM A-36.
For casks fabricated after October 31, 1980, low carbon steel shall conform to ASTM A-516, Grade 70.
Both yield and ultinate stresses of A-516, Grade 70, are slightly higher than those of A-36 (5% greater yield; 20% greater ultinate).
For 3
conservatism, the lower A-36 values are used for analysis through-out this report.
Specific properties are as follows:
Per MIL-HDBK-V 55,000 psi F
=
tu 36.000 psi F
=
ty 3S,000 psi T
=
su 90,000 psi F
=
3g Lead shielding will possess those properties referenced in ORNL-NS3C-68, Table 2.6, Page 84.
Lid studs are all of SAE Grade 5 quality possessing the follow-ing properties, per ASTM A325 and A449:
_1" ik" Proof Load:
78,000 psi 74,000 psi Tensile Strength: 115,000 psi 105,000 psi q
1-2
Revicion 3 December 17, 1980 The secondary lid closure studs are examined in a cc.nparable fashion.
Conservatively, the total payload mass of 7500 lbs. is assumed to be reacted by the secondary lid studs.
Thus, the total f
secondary lid stud load is estimated as:
(W +W ) a cos R
=
p (2000+7 500 ) (19.1) cos 43.5
= 131619 lbs.
=
i Since there are eight secondary lid studs (1-8 UNC, SAE Gr. 5), each I
stud load is 16,452 lbs.
The tensile strength of the stud is:
f3 f
P
FA
(115,000)(.563) = 64745 lbs.
t I
i Thus the margin of safety of the secondary lid is:
l f
M.S.
= 64745/16452-1 = +2.94 Therefore, it can be safely concluded that the package can survive a normal corner drop.
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l 18?.03 ii 1-19
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