ML20137M821
| ML20137M821 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 01/23/1986 |
| From: | Reinaldo Rodriguez SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| To: | Miraglia F Office of Nuclear Reactor Regulation |
| References | |
| REF-GTECI-A-49, REF-GTECI-RV, TASK-A-49, TASK-OR RJR-86-06, RJR-86-6, TAC-59976, NUDOCS 8601290079 | |
| Download: ML20137M821 (4) | |
Text
r 8
4 esuu.
SACRAMENTO MUNICIPAL UTILITY DISTRICT C 6201 S Street, P.O. Box 15830. Sacramento CA 95852-1830,(916) 452-3211 RJR 86-06 AN ELECTRIC SYSTEM SERVING THE HEART OF CALIFORNIA January 23, 1986 DIRECTOR OF NUCLEAR REACTOR REGULATION ATTN FRANK J MIRAGLIA JR DIRECTOR DIVISION OF PWR LICENSING-B U S NUCLEAR REGULATORY COMMISSION WASHINGTON DC 20555 ASSESSMENT Of FRACTURE TOUGHNESS Of THE RANCHO SECO REACTOR VESSEL
References:
- 1) Federal Register Vol. 50, No. 141, July 23, 1985
~
- 2) " Analyses of Capsule RS1-D Sacramento Municipal Utility District Rancho Seco Unit 1", BAW-1792, October, 1983
- 3) " Vessel Fluence Reduction - Fuel Cycle Study", BAW-1884, January, 1986
- 4) " Pressurized Thermal Shock Evaluations in Accordance with 10 CFR 50.61 for Babcock & Wilcox Owners Group Reactor Pressure Vessels", BAW-1895, January, 1986
- 5) " Evaluation of the Atypical Weldment", BAW-10144-A February, 1960 The District has evaluated the nil ductility transition temperature, adjusted for the effects of neutron irradiation (RTpys) in accordance with Reference 1, for Rancho Seco reactor vessel beltline material.
Table 1 presents neutron fluence values for the life of Rancho Seco.
Values through Cycle 7 are based on actual fuel configurations in the reactor core.
Values for Cycle 8 through the end of life are projections.
Key assumptions are:
8601290079 860123 PDR ADOCK 050 2
gf
/pk
- ._'n="""
lMT.%
L_
RJR FRANK MIRAGLIA JR January 24 1986 Rancho Seco will go to a very low leakage fuel shuffle scheme (the "in-in-out" fuel shuffle) starting with Cycle 8.
End of Cycle 7 fluence is conservatively estimated to occur on December 31, 1986.
The fluence after Cycle 7 is conservatively based on a capacity factor of 80%.
Table 2 presents data for specific areas and welds of the reactor vessel.
The abbreviated descriptions refer to the lower nozzle belt; upper and lower shells; upper, middle and lower circumferential welds; and upper and lower longitudinal welds.
The last lower longitudinal weld was made from two heats, with ID referring to the inner 73% and OD referring to the outer 27%. The copper (CU) and nickel (NI) content and initial RTNOT(I) are as specified in Reference 4, which in turn references Babcock & Wilcox reports BAW-1820 and BAW-1799.
The margin of uncertainty in RTNOT is as specificed in Reference 1.
Values of RTPTS are given for equation 1 of Reference 1, since equation 1 gives the lower value in each case.
NVT is the peak fluence seen by each area or weld. As can be seen from the table, the screening criteria are not violated.
There is a low probability that the lower longitudinal inside weld contains atypical weld material, as described in Reference S.
The Babcock & Wilcox Company has undertaken a study of this material, and has found that the actual neutron radiation response differs significantly from that predicted in Reference 1.
Reference 4 describes the material properties and the basis for the projection of RTNDT.
The calculated value is 251*f at license expiration, at a fluence of 6.9 E18 n/cm2, which does not violate the screening criterion, i
Reference 4 will be submitted to you by the Babcock & Wilcox Company on behalf of the B&W Owners by January 23, 1986.
If you have any questions, please contact Rich Myers of my staff at (916) 732-6023.
9
~
s R. J. RODRIGUEZ ASSISTANT GENERAL
- NAGER, NUCLEAR
TA8LE 1 EXTRAPOLATION
- OF PRESSURE VESSEL FLUENCE Peakflux >1Mev at Vessel Wall Peak Peak Cycle (n/cm2/sec at Fluence /EFPY Cycle Integrated Cgcle Integrated full power)
(n/cm x10l9)
EFPY EFPY (n/cm x10l9) (n/cm x10l9) 2 I to 3 1.94 x 1010(c)
.06122 2.82 2.82
.1726
.1726 4
1.30 x 1010(c)
.04125
.63 3.45
.0260
.1986 5
1.34 x 1010(c)
.04229
.83 4.28
.0351
.2337 6
1.09 x 1010(c)
.03440
.94 5.22
.0323
.2660 7(a) 1.12 x 1010(d)
.0358
.10 5.32
.0036
.2696 10 7
1.12 x 10
.0358
.93 6.15
.0333
.2993 9
8 to (b) 7.51 x 10
.0237(e) 17.42 23.57
.4129
.7122 (a) - January 1, 1986 - Present date (for submittal)
(b) = October 11, 2008 - Present license expiration.
(c) = Value from Table D-2 of BAW-1792 (Reference 2).
(d) = Cycle 7 from Telecon to 8&W Oecember 5, 1985.
(e) = Cycle 8 value = Cycle 7 value divided by VLL flux ratio (1.51) from Table 4-2 of 8AW 1884 (Reference 3).
^CF =.80, E0C 7 = December 31, 1986 i
TABLE 2 RTPTS VERSUS TIME RTPTS CALCULATED FOR JANUARY 1,1986 (PRESENT DATE)
WELD HEAT #
CU NI I
M SCREEN RTPTS NVT NZ 8LT FV4823
.15
.68 10.
48.
270.
120.
2.0 E+18 U SHELL C50621
.12
.60 4.
48.
270.
102.
2.7 E+18 U SHELL C50622
.12
.60
-10.
48.
270.
88.
2.7 E+18 L SHELL C50701
.10
.58
-20.
48.
270.
68.
2.7 E+18 L SHELL C50702
.10
.58
-20.
48.
270.
68.
2.7 E+18 U CIRC WF-233
.29
.68 0.
59.
300.
186.
2.0 E+18 M CIRC WF-154
.31
.59 0.
59.
300.
199.
2.7 E+18 L CIRC WF-233
.29
.68 0.
59.
300.
186.
2.0 E+18 U LN WF-29
.23
.63 0.
59.
270.
162.
2.6 E+18 L LN WF-29
.23
.63 0.
59.
270.
163.
2.6 E+18 L LN ID WF-70
.35
.59 0.
59.
270.
217.
2.6 E+18 L LN OD WF-29
.63 0.
59.
270.
163.
2.6 E+18 RTPTS CALCULATED FOR OCTOBER 11, 2008 (LICENSE EXPIRATION)
WELD HEAT #
CU NI I
M SCREEN RTPTS NVT NZ BLT FV4823
.15
.68 10.
48.
270.
140.
5.4 E+18 U SHELL C50621
.12
.60 4.
48.
270.
118.
7.1 E+18 U SHELL C50622
.12
.60
-10.
48.
270.
104.
7.1 E+18 L SHELL C50701
.10
.58
-20.
48, 270.
81.
7.1 E*18 L SHELL C50702
.10
.58
-20.
48.
270.
81.
7.1 E+18 U CIRC WF-233
.29
.68 0.
59.
300.
225.
5.4 E+18 M CIRC WF-154
.31
.59 0,
59.
300.
241.
7.1 E+18 L CIRC WF-233
.29
.68 0.
59.
300.
225.
5.4 E+18 U LN WF-29
.23
.63 0.
59.
270.
193.
6.8 E+18 L LN WF-29
.23
.63 0.
59.
270.
194.
6.9 E+18 i
L LN 10 WF-70
.35
.59 0.
59.
270.
265.
6.9 E+18 j
L LN 00 WF-29
.23
.63 0.
59.
270.
194.
6.9 E+18 i
,. - -