ML20064E462
| ML20064E462 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 03/05/1994 |
| From: | SARGENT & LUNDY, INC. |
| To: | |
| Shared Package | |
| ML18059A868 | List: |
| References | |
| CMED-58597, CMED-58597-R, CMED-58597-R00, NUDOCS 9403140308 | |
| Download: ML20064E462 (5) | |
Text
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ATTACHMENT 3 Consumers Power Cortpany Palisades Plant Docket 50-255 FLAW EVALUATION FOR CHECK VALVE IN CONTAINMENT SUMP SUCTION
{
March 6, 1994 9403140308 940306 PDR ADOCK 05000255 P
s i
s SARGENT & LUNDY Flaw Evaluation for Check Valve in Calc No.:
ENGINEERS Containment Sump suction:
CMED-58597 Rev. O Page lof 4 Consumers Power Corp.
Prepared by
~}m.(r3b L 9/S?Q Palisades 9400-40 d
/
Safety-Related Reviewed bybuk 1 h P. H. H ow3 - 5 dH 3
[7 b r r 3/6/h Approved by f
/
/7
Purpose:
An inspection of the subject check valve identified a through wall flaw. This evaluation determines the stability of this flaw when subjected to SSE and post LOCA loads.
The valve b a cast stainless steel, A351 grade CF8M material.
Flaw characterization: For the purposes of this calculation the flaw is characterized as a through wall circumferential flaw with length, L. The circumferential flaw orientation is chosen because the bending loads caused by the weight load and SSE event will only affect flaw stability in this orientation. Therefore, this is the conservative flaw orientation.
s u!a crack lengm L : 20 in OD : 24 in Nominal outside diameter t :0 58 in Measured Thickness ( UT Report dated 3/1/94)
Material properties of A351 grade CF8M:
= 23300 psi Minimum yield and ultimate stress from 1983 a y ASME Section til Appendix I at 300 F o
68500 psi u
or: hay +o)
Flow Stress at Design Temperature as defined in SRP u
3.6.3.
o p = 4.5910 psi Loading:
From DIT No. CPC-017-01 During normal operation this line is only subjected to the static pressure head from the containment sump, therefore the only continous load is the weight and pressure. The following stresses are an envelope of CK-ES3166 and CK-ES3181 valves.-
P 60 0 psi Design Pressure WT = 1129 psi Weight stress SSE :6892 psi SSE stress OBE -
OBE stress 1
TH = 687 psi Post LOCA Thermal expansion stress
.l l
.l
SARGENT & LUNDY Flaw Evaluation for Check Valve in Cale No.:
ENGINEERS Containment Sump Suction:
CMED-58597 Rev. O Page 2 of 4 The above stresses are based on the attached pipe section modulus. Therefore, stresses at the tee and valve end junction are modified as follows:
t
- 0 375 in norn t
m :WT."*
= 729.957 psi o
a wt t
t o be ; OBE "
- a be = 2.22810 psi 3
o o
t t
SSE "
- 3 o
= 4.45610 psi o 33e :
3se t
t th " 444 I8I 'P8i oh 8
t Note that the line is at ambient condition during normal operation. In Post LOCA condition this line may be required to circulate coolant from the containment sump. During this mode of operation a thermal transient will occur as the hot fluid from the containment sump is drawn through this line. However, the thermal gradient stresses in the pipe wall (bending stress in both hoop and axial directions) have no significant effect on the stability of the postulated through wall crack due to the following reasons:
- The radial temperature distribution creates a local through wall bending stress which is eliminated as the flaw propagates through wall.
- This radial temperature distribution develops a compressive stress field at the inside wall of the pipe preventing opening of the uncracked portion of the piping.
Therefore, the thermal transient through wall stress associated with post LOCA recirculation is not included in this evaluation.
Calculation:
This calculation is based on the methodology of Appendix C of the 1989 ASME Section XI code and the proposed Standard Review Plan 3.6.3, Leak Before Break Procedures, September,1987. The check valve is a cast A-351 grade CF8M material usually at room temperature, therefore it is not susceptable to embrittlement from thermal aging. The allowable stress index is based on of rom the Standard Review Plan instead of the 3Sm f
specified in the code because this produces the more conservative allowable stress index.
I' m -
Membrane stress 41 R = OD - t Mean radius 2
0 L'
Half crack angle 2R 0 = 0 854 rad i
SARGENT & LUNDY Flaw Evaluation for Check Valve in Calc No.:
ENGINEERS Containment Sump Suction:
CMED-58597 Rev. O Page 3 of 4 ASME Section XI, Appendix C requires the following Safety Factors:
SF :2.77 Normal / Upset Condition Safety Factor n
SF :1.39 Emergency / Faulted Condition Safety Factor e
Allowable Stress Index, SI, as defined in SRP 3.6.3:
(n- 0)- n f "*\\ '
1p l
p:
2
\\ f/
2c Si :--((2. sin (p)- sin (0))
n 4
Si = 3.064 10 psi The Z factor required by the SRP and ASME Section XI, Appendix C is a correction factor to account for the elastic-plastic material behavior. The Z factor is conservatively based on the Submerged Arc Welding, SAW, process-l Z 1.3 1
- 0 01.' 0 ] _ 4)f) in 7 = 1.56 j
Applied Stress Index for the 1
Normal / Upset condition Pb " " wt + " obe P :o h e
t
/
P e \\'Z ~ P ASi : SF ' Em*P b + SF /
n n
m n
ASI = 1.554 10
- psi 4
n Applied Stress Index for the Emarger$cy/ Faulted condition Eb " " wt + " sse P
oh t
e Pe)
ASl : SF. Pm+Pb + SF jl Z - P e
e m
t e
4 ASI
- 126610
- psi e
SARGENT & LUNDY Flaw Evaluation for Check Valve in Calc No.:
E NGIN EERS -
Containment Sump Suction:
CMED-58597 Rev. O Page 4 of 4 The additional margin for
)
normal /upsetis emegency/ faulted is S1 SI Margin Margin e
n ASi ASI n
e Margin =1.972 Margin = 2A 19 n
e l
==
Conclusion:==
Based on the calculated margin between the Allowable Stress Index, SI, and the Applied Stress Index, ASi and ASl, a circumferential through wall flaw of 20" would not propagate n
e and cause the collapse of this component during an SSE event.
1 i
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