ML20008F748
| ML20008F748 | |
| Person / Time | |
|---|---|
| Site: | 07109144 |
| Issue date: | 03/31/1981 |
| From: | CHEM-NUCLEAR SYSTEMS, INC. |
| To: | |
| Shared Package | |
| ML20008F746 | List: |
| References | |
| NUDOCS 8104210669 | |
| Download: ML20008F748 (22) | |
Text
_
1
~
O SAFETY ANALYSIS REPORT for CHEM-NUCLEAR SYSTEMS INC.
SGC 1 TYPE A RA0 WASTE SHIPPING CASK I
July 24, 1980 Rev. 1 January 1981 Rev. 2 March 1981 i
l Chem-Nuclear Systems Inc.
Corporate Headquarters P.O. Box 1866 Bellevue, Washington 98009 (206) 827-0711 g304210
,._-,-.._.__-.,__-_.,,,---,-~,.._,__._.,.--,-.,,,_,-.,_.-.-._____._.m---,-.,,x.
TABLE OF CONTENTS (Continued)
Page 9.
QUALITY ASSURANCE 9-1 9.1 Appendix 9-2 Approval Letter for CNSI Quality Assurance Program 9-3 NRC Form 311 9-4 Appendix A Response to NRC Request for information date 12/18/81, Docket 71-9144 A-1 Appendix B Accident Discussion B-1 2E "l
Revision 2 iv fiarch, 1981
i DTECTIVE PAGZ:S PAGE gg 1-1 January 1981
=
1-4
=
1-5 1-6 1-7
=
1-8 March,1981 1-9 1-10 I
1-11 January,1981 1-12 March,1981 1-13 1.3.1-1 January, 1981
=
1.3.1-2
=
1.3.2-1 1.3.3-1 l
1.3.3-2
=
1.3.3-3 1.3.3-4
=
1.3.3-5 i
1.3.3-6 l
1.3.3-7 l
1.3.3-8
=
1.3.3-9
=
1.3.3-10
=
1.3.3-11
=
2-1
=
2-2
=
2-3
=
2-4
=
2-6 2-7 2-8 Rev. 2.
March, 1981 v
EFFECTIVE PAGES (CONT.)
PAGE DATE 2-82 January 1981 2-83 2-84 a
2-85 a
2-86 a
2-87 March 1981 2.10.1-1 2.10.2-1 January 1981 a
2.10.2-2 a
2.10.2-3 a
3-1 a
5-1 a
5-2 a
5-3 a
5-4 a
5-5 March 1981 5-6 January 1981 5-7 a
5.5.1 1 a
5.5.1-2 a
5.5.1-3 a
5.5.1-4 a
5.5.1-5 a
5.5.1-6 a
5.5.1-7 a
- 5. 5.1 -8
=
- 5. 5. 2-1 l
5.5.2-3 l
5.5.2-4 a
5.5-1 a
(
5.5-2
=
(
5.5-3 a
l 5.5-4 a
5.5-5 a
5.5-6 a
5.5-7 a
6-1 viii Rev. 2, March 1981
e EFFECTIVE PAGES (CONT.)
.l DATE-PAGE March 1981
-i i
7-2 January 1981 4
4 9-1 A-1 H'
A-2 A-3 II l
A-4 a
l A-5 March 1981 2.10.1-2 H
4 2.10.1-3 a
i 2.10.1-4 a
a 7-3 a
7-4 a
7-5 a
a iv u
1 y
viii a
ix a
a B-1 a
B-2 a
B-3 I
B-4
]
B-5 4
l 1
i i~
i i
Rev. 2, March 1981
~
fx I
N w----
rw-.,-,-,w---,--=m.,
--n
.-we-->
.4--e rtm
-w-v-*-r=--e-e-e---emr--
-r-w-m+
e"-,--
.y v-y',-v---we-=-*-v
-w-<t,"w--v r
---m---
~
1.2.4 Steam Generator Lower Assembly Sealino Containment The Steam Generator Lower Assembly is sealed and preoared for shipment by the folicwing operations: (Ref. Figures 1.2-3, 1.2-4, 1.2-5.
The top of the assembly (transition cone cut-line) 1.
is sealed with a cap assembly.
This cap assembly consists of a 3 5"
thick 24-inch wide, steel l2.
plate skirt ring rolled to a 12 '-6" 0.D..
The ends of the ring butt welded with a full pene-tration weld.
The top of the skirt ring is then capped with a3-5"' thick flat plate,12'-2" in di-l 2-ameter, welded to the skirt ring with a l 1/2-inch fillet weld, 1-inch thick at the throat of the weld. The complete cap assembly is welded to the Steam Ganerator Lower Assembly transition cone cut line with a 1 1/2-inch fillet weld, 1-inch thick at the throat completely sealino the cap to the transition cone and the internal primary system tubing.
The bottom of the Steam Generator Lower Assembly, 2.
at the Chnnel Head cut-line, is closed with a g
3 - 5" thick,11'-1 diameter steel plate welded to the Steam Generator Lower Assembly shell by a 1 1/2-inch fillet weld, 1-inch thick at the throat.
3.
All Steam Generator Lower Assembly small nozzle connections (i.e., (2) Bottom Blowdown, 2-in.; (1)
Shell Drain, 1-in.; (1) Long Range Level Top, 3/4-in.) are sealed by inserting a minimum 2-in.
long barstock welded closed with an appropriate fillet weld around the 0.D. of the protruding.bar-stock end.
All Steam Generator Lower Assembly 6-in, handhole 4.
openings are sealed with 2-in. minimum thickness steel plate, 5.990-in.
0.D.,
welded with an ap-propriate fillet weld to the inside of the hand-hole opening.
The handhole cover plates are put back in olace and bolted af ter welding as an ad-ditional cover.
All weld material will be E70XX welding electrodes or equivalent, and welding is done in accordance with ASME Section IX procedures and standards or equivalent.
Steam Generator Lower Assembly Shielding Preparation 1.2.5 Before loading the assembly into the shipping cask, the as-sembly shell and closures will be surveyed to assure thac no reading above the cask design limit of 200 mR/hr is evident.
1-9 Revision 2
- March, 1981
'=
12' 10' DIA
- NAIE f-- - -
12'- (.' Ol A
[
g
.'Iz'-t otA i
/
j I
l
.9
\\'
' b
!!1T LA*r N'
4 N
Ysun maq
\\
\\
85NlirLA Thu$1Tiew 3
C#LE SC 2.
8
- 3,,5*
-- [
=
m 4.
twnm Txacow i
(9 i
D9 Tid 4r STEAM
~~
M4E.RATOR SWF.LL
.09TT8M DLOW (%7WU o
JJB2,'LLE TYP LA CWAMWEL WEAD t
-END l
I s
7.
CUT WE 7 y o
f
! 11'- l' cia t
~M 20TTOM S EAL 2
=#
f S" PLATE STEAM GENERATOR LOWER ASSEMBLY (SGLA)
SEALING CONTAINMEWT FIGURE 1.2-3 Fev. 2 1-10 March, 1991 l
f Actual survey readings of the generators during regular shutdowns, and in a drained conditions indicate contact levels well below 200 mR/hr.
In the event areas of the Steam Generator Lower Assembly and its plate seal closures I
are found to exceed the 200 mR/hr limit, additional steel and/or lead plate shielding will be f astened by clioping and/or welding over these areas on the SGLA outer shell surface.
R Dose rates at these points will not exceed 1 /h'r at 3 ft prior to the installation of additional shielding.
d 4
1-12 Rev. 2 March, 1981
~~
APPENDIX 2.10.1 Tiedown Criteria Discussion Due to the large mass of the SGC-1 package it is ur.rsalistic to demon-strate that the accelerations required in 10 CFR 71.31(d)(1) could ever be reached under normal conditions of transport.
Examining the actual transport conditions, there are two seperate environments:
- 1) Land Transoortation and 2) Marine Transportation LAND TRANSPORTATION:
The loads that the cask could possible see during normal land transport The are greatly affected by its transport controls, and trailer It is highly on a hydraulic suspension olatform trailer with 104 wheels.
unlikely that any notictable vertical or horizontal accelerations will be The package is further protected by the transport controls It should be noted genersted.
and procedures requiring traffic control and escort.
that for normal loads of this size only friction and gravity are used te secure the load to the trailer. loads in excess of friction is added conser downs carry any lateral tism.
Additionally securing the package to the trailer so that the is the maximum tiedown the package can trailer stays with the package have in the vertical direction.
MARINE TRANSPORTATION:the package can be subjected to during marine transc These actual loads The loaos that are greater than those imposed during land transport.
This is further are far less than those loads imposed by 10 CFR 31 (d).
demonstrated by the L.R. Glosten and Associates, Inc, study prepared fcr the transport of the Surry Steam Generator to Hanford intitled "A Study of the Single Voyage Risk Levels Associated with Extreme Motion values for a Barge Voyage from Norfolk, Virginia to Astoria, Oregon", January, This study develops extreme environments based upon a winter voy-The maximum g loadings 1980.
age which was dominated by North Pacific storms.Added conservatism is included developed are considerably less than lg.
N552, Draf t #3, October 1976, by using the proposed rules of ANSI 14,
" Proposed Guide for Water Transportation of Irradiated Nuclear Fuel".
Section IV of the proposed guide, specifies 1.5g loadings in the horizontal direction with sufficient vertically in the 'tiedowns to allow recovery of Note that no allowance was the package with the hull, in case of capsizing.taken for friction The marine tiedown of the SGC-1 package are designed to withstand load This exceeds the criteria of ANSI N-14, N552 1.5 g's in all directions.
Draft #3, October,1976, checking the tiedown criteria for simultaneou loadings from pitch, heave and roll.
a) " Rolling 15* each side (60*) in 5 seconds"
" Pitching 4* half amplitude (16*) in 5 seconds" b) c) " Heaving use 0.3 g's" Assuming a sine form for the motion Revision 2 March, 1981 2.10.1-1
e
= A sin Bt h = AB cosBt de2 = -AB sin Bt 2
dt' Boundary Conditions 0
t
= 1.25 secs. (1 period) t
=
i 0
0
=.262 radians 0
=
h= max
=0 der den 0
y=
y = max From A
h = AB cos Bt 1.25 t
=
A(B) cos B (1.25) 0
=
A and B / 0 Therefore Cos Bt = 0 Bt = n/2 radians n/21.25 sec = 1.26 radians /sec.
B
=
A sin 1.26 (1.25)
A A sin n/2
.262
=
=
=
h; To find max d
.262 (1.26)2 sin 1.25 (1.26)
AB2 sin Bt
=
=
dt 2
.416 radians /sec
=
A bounding condition is for the center of bouyancy to be 20 ft below the CG at of cash.
2
.416 (20) de2 R 8.313 ft/sec,
=
ar
=
=
dt'
.26 g's.
=
Similarly for pitching Boundary conditions Revision 2 2.10.1-2 March,1981
~
t
=0 t
= 1.25 sec.
4
=0
= 0.07 h
=0
= max db*
dp
=0
- "8*
dt' dt" 4
= C sin Dt h = C D cos T t 3=-CDsinDt 2
h = C D cos Dt Implies D = 1.26 radians /sec.
2.
1.25 sec.
At t
=
C sin [(1.26)(1.25)]
o
= 0.070
=
C
=.070 3=-CD 2 sin Dt max
=.070 (1.26): sin [(1.26)(1.25)]
2
=.111 radians /sec The cask CG is within 20 ft of the CG of loaded barge
= -(20) (.111) 2.217 ft/sec 4p
=
=
= 0.07 g's.
Combining all accelerations simultaneously Yap 2 + a * + ah*
A
=
r V(.26)2+ (.07)2 + (.3)2
=
.40 g's.
=
This is considerably less than the 1.5 g's thct the tiedowns are designed for.
The sufficiency of the 1.5 g criteria can also be checked by looking at the accelerations that are predicted in "A Study of the Single Voyage Risk Levels Associated with Extreme Motion Values for a Barge Voyage from Norfolk, Virginia, to Astoria, Oregon."
L.R. Glosean and Associates, Inc.1980. This is a detailed study of the barge motions resulting from various sea conditions. The results of the studies include roll, pitch, 2.10.1-3 Revision 2 March 1981
and heave. At a 1% risk level without consideration for seamanship at 8 knots, the following acceleration values were determined: Surge: 9.75 2
2 2
f t/sec, Sway: 23.6 f t/sec and Heave:ll.4 ft/sec. Adding these 2
vectorially, max acceleration equals 27.95 ft/sec or 0.87 g's. 'If the barge was to turn over in these type of seas, it would see basically the same motion and forces, except that gravity would have to be added to the heave component. The speed would be zero knots.
The accelera-tions are predicted to be: Sways 23.6 ft/sec, Surge:10 ft/sec, and Heave: 41.7 f t/sec. This would give a maximum acceleration of 49. ft/sec 2.
or 1.5 g's.
An over turned barge is an accident condition. The design of tiedowns is based on withstanding 1.5 g's at yield.
In an accident condition the full strength of the tiedowns based on tensile strength can be applied. Therefore, the tiedowns would adequately keep the cask with the barge even if the barge turned over.
It should be noted that the probability of the barge seeing these maximums simultaneously is very small. There is even a smaller probability that the barge will capsize.
In conclusion, the 1.5 g tiedown criteria is adequate to secure the cask to a barge. The criteria is acequate for both the motions described in the ANSI N-14, N552 Draft #3, October,1976, document and those described by a study of barge motions (Glostan Report). The criteria is adequate even in accident conditions.
2.10.1-4 Revision 2 March,1981
~
The top of the tube bundle has a similar self-shielding cap-ability from innermost tube loop to the outer tube loops, with a final steel cap of 3-5" thick steel plate welded to I ?-
the end of the SGLA shell.
.The open ends of the tubes penetrating through the tube sheet are spaced approximately 21/4-in. from the 3-5" thick plate f F-welded to, and closing, the bottom of the SGLA shell.
There is 72-in of air space between this bottom SGLA closure plate and the inner surface of the cask end plate.
There is 8-in. average air space between the outer SGLA shell wall and the cask plate inner surface.
There is 12-in. approximately of air space between the top O
cap closing the SGLA shell and the inner surface of the cask end plate.
5.4.3 Actual Radiation Readings Contact radiation readings have been made from typical steam generators, shcwing contact reading levels ranging from 50 mR/hr at the bottom of the channel head to 75 mR/hr on the sides of the SGLA.
Figure 5.5-5 in Appendix 5.5 illustrates these readings.
5.4.4 Shielding Criteria As a conservative standard, a nominal reading of 200 mR/hr on the surf ace of the SGLA was established as a cask design limit, even though much lower levels of radiation are expected.
Revision 2 5-6 March,1981
li 7)
Move the lower half / payload and trailer to the final unloading area under the lifting device.
8)
Reuove the internal tiedowns.
9)
Lift the payload out of the lower half.
10)
Move the trailer and lower half of the cask out from under the payload.
11)
Set the payload down.
12)
Inspect the cask and take any necessary surveys.
13)
Reassemble cask internal tiedowns.
14)
Place the upper half on the lower half per the procedures set forth in Section 7.1.
7.3 Preparation of an Empty Package for Transport 1)
Follow the same steps as set forth in Section 7.1, except omit the steps involving the contents.
7.4 Controls for Ground Transoortation 7.4.1 Maximum speed for the loaded transporter and cask is 10 mph.
7.4.2 On all curves and grades the transcorter will be slowed to a walking speed or less.
7.4.3 A back-up prime mover will be with the loaded transporter.
7.4.4 A mechanic with reasonable spare parts for the transporter and prime mover will be with the transporter.
7.4.5 A detailed inspection of the route is made prior to the 2.
movement identifying all culverts, overhead wires, etc. Wires are raised as necessary before the movement.
Required rein-forcement of the culverts or other weak areas are made either by replacing the culvert (coordinated with the applicable Highway Department) or by using prefabricated portable jump bridges which span the weak area. These bridges are existing standard equipment that are used in heavy hauling.
Imediately prior to the transport, the route is inspected with the applicable highway officials. During the actual transport the roadway is reinspected prior to the transporter moving.
7.4.6 Prior to barge unloading, all necessary Federal, State and l
County officials, including emergency organizations, will be notified of the impending haul and latest update of schedule.
7-2 Rev. 2 March,1981
i 7,4.7 Prior to moverrent of the SGC-1 package loaded or unloaded over public roads, a detailed traffic control plan will be worked out with the applicable authorities (State police, County sheriff or police) for the particular route. The actual traffic control will be coordinated by the applicable law enforcement agency. Depending on the particular road, route and nonnal traffic patterns, the traffic control plan will take one of two fanns: 1) traffic in both directions stopped while the transporter is moving, or 2) traffic in the direction of travel of the transporter is stopped whi?e the transporter is moving.
In the first case, the transporter will move up to a predeter-mined passing point and stop. The traffic will then move around it in both directions as directed by the applicable officials. The next section of roadway is then blocked off and the transporter continues to the next predetermined point.
In the second case, the oncoming traffic is slowed and directed around the transporter convoy. Traffic moving in the direction of the transporter follows the convoy to a predetermined passing point. The transporter is then stopped while the traffic is directed around the convoy.
2 7.4.8 At all times the transporter (prime mover, hydraulic trailer and:
cask) move in a convoy. This convoy will consist of a minimum l of the applicable traffic control personnel, backup prime mover,!
health physics personnel with survey equipment, and portable barrier material and other emergency equipment, mechanic with tools and spare parts, comunication equipment, and emergency equipment. Ccnstant comunication will be maintained between the lead and rear vehicle and prime mover of this convoy. The lead and rear vehicle will have flashing warning lights.
7.4.9 Comunication will be available in the convoy to comunicate with appropriate emergency organizations and/or response teams.
7.5 Controls for Marine Transoort 7.5.1 All marine equipmsnt including barge and tiedowns will be inspected by the Coast Guard and a marine surveyor prior to the start and at completion of each trip as required.
7.5.2 The route of the barge and cask will be coordinated with the Coast Guard. Alternate routes in case of bad weather will also be designated.
7.5.3 Daily contact will be made with the tug which will report its position and status.
7-3 Rev. 2 March, 1981
7.5.4 Marker buoys will be placed on tha barge.
Insurance for recovery of the cask / steam generator where 7.5.5 required will be in effect.
When in ports the barge transporting the loaded cask will 7.5.6 be located in accordance with the Coast Guard and Captain of the Port instructions to minimize the probability of collision with pasrt1 harbor traffic and explosion or fire from nearby hazardous materials.
r The loaded cask, barge and tug will make a minimum number of 7.5.7 Ports-of-call other than departure point and
[
ports-of-call.
unloading point will only be made in case of an emergency (mechanical failure, very severe weather).
7.5.8 The barge will be under single tow.
The movement of the barge in the Savannah River will be coordi-7.5.9 nated with the U.S. Amy Corp of Engineers to insure adequate water depth.
7.5.10 The Coast Guard and other appropriate authorities along the marine transport routing will be contacted prior to the start of any transport operations. The Coast Guard will be contacted
+
daily during marine transport to update status and location.
i 7.5.11 In the event of an accident during marine transportation, the Coast Guard, NRC and other appropriate authorities will be notif-;
Necessary precautions and activities to insure j ied immediately.
Corrective l the public's safety will be instituted immediately.
and/or recovery requirements will be identified and programs developed.
7.6 Health Physics Controls Prior to each loading operation the cask will be surveyed 7.6.1 for both external and internal contamination. Decontamina-tion will be carried out, as required.
Continous radiation monitoring will be perfomed during all 7.6.2 phases of the loading operation.
Following cask loading a contamination survey will be made.
7.6.3 Decontamination of cask external surfaces will be effected The cask will be released for shipment when as required.
i contamination levels are at or less than the limits set forth in Section 173.397 of the 00T regulations.
Radiation surveys of the loaded cask will be perfomed to
[
7.6.4 detemine that radiation levels do not exceed 200 mr/hr at the surface,10 mr/hr at 2 meters (6.6 feet), and 2 mr/hr in the occupied portion of the prime mover. iediation surveys will be made in occupied areas of the tug when it is along side the barge for maneuvering.. Personnel dosimetry will be supplied as required.
7-4 Rev. 2 March,1981
7.6.5 A Health Physics Technician will be available during all phases of marine and ground transport. The Technician will have all required instrumentation such that he will be able to make radiation surveys and evaluate the results of such surveys.
7.6.6 Access to the loaded cask will te controlled during all 7,
phases of marine and ground transport. During ground trans-port appropriate barricades, posting ~etc. will be used to restrict access to the cask when it will be parked for longer than one hour.
7.6.7 Unloading and final burial at the disposal facility will be carried out in accordance with specific procedures for that operation.
L Rev. 2 7-5 March,1981
~
t
(
APPENDIX B ACCIDENT DISCUSSION Possible accidents involving the SGC-1 cask ar are inherent with its movement that make most coninon accidents unli The tremendous rigidity built into the cask and its payload a steam ge lower assembly (SGLA) causes most of the energy of any type of SGC-1 package to be absorbed by the surface being impacted.
The type of accident where the question of loss Two areas are addressed.of shielding is raised and the situation wher Loss of Shielding The first type of accident is unlikely, due to the strength of the pac No concievable accident was detennined to cause the SGLA to sep Even if it did, the required 200 mr/hr. contact reading of the 1 SGLA would not exceed the 1 R/hr at 3ft. requirement for accide the cask.
~
Although the welds may crack on the end plates of the SGLA, no ac could be derived where they could come off.
To give an idea of the energies and forces required, the 30 ft.
cask on the small end was examined.
722,000 lbs x 30ft 12 in Energy to be absorbed =EA= hw =
ft
= 260 x 10' in-lbs.
Consider the volume of steel required to absorb this energy.
average stress required for plastic defonnation (Sp)
= EA Vol. steel Sp average
- 45,000 psi for ASTM-A516-Gr.70 Assume 8
8 in Vol. steel = 260 x 10'_
= 5.78 x 10 45 x 10' Assuming a flat end drop on the small end.
The steel defonned is the side walls, 2.5 in, thick.
[
8 8
2.312 x 10 in Area of steel
= 5.78 x 10 /2.5 8
=
[
Perimeter = 2 (72) x Radius = 72 in.
Diameter = 12 f t.
h=2.
= 5.11 in.
Ph.
2 Area
=
Only 5.11 in, of the cask would be defonned.
Rev. 2 B-1 March,1581
The 5.11 inch deformation is insufficient to cause contact with the ca It is recognized that not and the SGLA with the channel head cut off.
all of the deformation will occur at the localized area, but the total deformation remains the same.
Similarly, corner drops and side drops would require the same or less The deformation required to absorb the energy amount of defonnation.
could cause the steam generator lower assembly to come in contact with Once the two walls come in contact, the loads are pro-jected into the SGLA with very little deformation, since the lower assembly the cask wall.
The small end has a 21 in. thick tube sheet is a highly stiffened shell.
Throughout the entire assembly within 21 in, of the welded seal plate.
there are tube supports which stiffen the shell preventing a catastrophic These supports greatly reduce the potential of any
?_
failure of the shell.
type of accident that will separate the steel shell f om the contaminated tubes.
Based on the foregoing, it is highly improbable that an accident could Furthermo e occur that would cause the cask to separate from the SGLA.
it is even more unlikely that the plates welded on the SGLA with li in.
fillets will separate from the assembly after the majority of the energy is absorbed by the cask.
The tremendous amount of force required for this deformation makes such Based on the 30 ft. drop previously described, an accident unlikely.
the average force seen by the cask is:
A = pt = 2 n (72) (2.5) = 1131 sq. in.
= 1131 sq. in. (45,000) = 50.9 X 10' lbs.
Force This tremendous force would find very few if any objects capable of reacting it along a normal barge route or overland route.
t l
l l
Rev. 2 0-2 l
March, 1981
SUBMERGENCE OF SGC-1 Although The SGC-1 cask's primary mode of transport is by barge transport.
all possible precautions are taken to have quality equipment and to avoid accidents,the possibility of the package sinking does exist.
This corres-The cask gasket is designed for 25 psig pressure differential.
This is greater than the recorded depth of ponds to 56.25 ft. of seawater.
approximately 50 ft. for the rivers and bays this cask is expected to travel.
The area of greatest concern would be The cask can react these pressures.
the _end.pl ates.
From Roark, and Young, Formulas for Stress and Strain, 5th ed. McGraw-Hill page 371, table 24 for a semicircular pi0te E
2 max. stress =,.42 ga t'
a = radius of plate t = thickness q = load per unit area Maximum stress =.42(25) 85 for large and 2
(2.75)'
= 10031.4 psi Margin of safety on yield.
M.S. = 36000 - 1 = 2.59 1D031.4 Therefore, even if the gasket holds to a higher pressure, the gasket is likely to fail before the end plat s, equalizing the pressure.
8-3 Rev. 2 March,1981
((.
In an accident situation it cannot be guaranteed that the cask flange or the cask welds will remain intact such that when inmersed there would be no leakage of water into the cask equalizing. he. pressure.
t The.second barrier against water mixing with' the radioictivjty is the steam 9enerator lower section itself. The only end of concern is the small end where the end plate seals the open tube ends.
2 a = 10' 91" From Timoshenko, S. Strength of Materials Part II. Krieger, N.Y.1956 page 97. For a circular plate with fixed edges.
2 2
Mr = La Max stress = 3/4 ca 8
t' 2_
For a minimum 3'in. plate Maximum stress at failure is 70,000 psi (64.63)'4 113.14 psi q
=
This is equivalent to 257 ft of sea water.
Examining the weld:
The weld will react to the applied bending moment.
hl Fw The reaction force of the weld can be applied at the center of the weld throat.
B-4 Rev. 2 March,1981
1
(_
1 1.06 in.
1.5 sin 45' L
=
=
Mr = L Fw Min weld material tensile = 70,000 psi Y
Fw =.707 (70,000) (1.5) 74235 lbs
=
in 39369 lbs Mr = 1.06 (74235)
=
2
= 39369 75.4 psi 39369(8)
=
q
=
(64.63)3 2
Approximately 171 ft. of sea water Although the welds and plate on the larger end will see greater moments and stresses and will fail at a lesser depth, the consequences are less. The large plate only ccvers the secondary side of the steam generator. The tubes exposed have been hydrostatically tested well above the 2000 psi operating pressure they have operated at. Any damaged and plugged tubes would have a very small release. They have also been thoroughly flushed in operations by the secondary side water.
I 1
(
l l
B-5 Rev. 2 March, 198{ g o g
- - -