PLA-6750, Response to Request for Additional Information on Proposed License Amendment Nos. 307 and 278
| ML112380639 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 08/26/2011 |
| From: | Rausch T Susquehanna |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| PLA-6750 | |
| Download: ML112380639 (11) | |
Text
Timothy S. Bausch Presderrt & CHO Niklear Officer AUG 2 6 all PPL Susquehanna, LLC ft Salcrrl Boulcvard tPt.
Lierwi;:k. PA 1S603 570542.5,445 Fax 570.542. i.50,1 Israuseh@ppiwc+.com l.?. S. Nuclear Regulatory Commission Attn: Doctmient (1 -2,ontrol Desk Mail Stop 0-P1-7 NN'ashington. DC 20555-0001 SUSQUEHANNA STEAM EI,ECTRIC STATION RESPONSE T() REQUEST' FOR.ADDITI( -)NAL INFORMATION ON PROPOSED LICENSE AND:NI/Nil:NI NOS. 307 21ND 278 PI A-6750 Docket No. 50-387 and 50-388 l&fcrcnce:
(P1. A 6(542) from T S. Rausch (1)PIJ tc 1)o,-,-urwmt Contvoi Des/ (NRC),
proriascri tonenchnoit Nra. 307 10 I iccri.ve NPF-f4 and Proposed Amendment No. 7 78 to License N1,F-22 Change to 'reeltnic(11,..pcciticollot1 Surveillance Requiretncnts (SR.) 3 4 3,1 to Revise the tower Surveillance Thlerance,s," dated November 10, 2010.
This letter is
Susquehanna, I.,LC's (1 3P1..) response to it request for additional information received from the NI C in an email dated July 21 : 2() 11. This email requested inforrnaticm regarding PPL's pr(17osed Technical Specification ehan:ile ptevionsly submitted tinder PLA -6642, to 1 "t vi the lower
of the tnitrn stotim safely reltrj vt,ilves nressur:::
hunt.
The response is
iNti...146 -i;Jfit,
tins ictter If you have questions, piease contak.; t. T. t:;:oddington at t 6 0 774-4019, Sincerel T. S. Rausch
Document Control Desk PLA-6750 Attachments; Attachment I: Response to NRC's Request for Additional Information Dated July 21, 2011 : Excerpt from Crosby Valve and Gage Company Procedure 1-11069 NRC Region 1 Mr. P. W. Finney, NRC Sr. Resident Inspector Mr. R. R. Janati. DEP/BRP
.Mr. -B. K. Vinci:0, NRC Project 'Manager
ATTACHMENT I TO PLA-6750 Response to NRC's Request for Additional Information Dated July 21, 2011 to PLA.-6750 Page 1 of 6 RA I-I American Society of Mechanical Engineers (ASMF) Code ha' Operation and Maintenance of Nuclear Power Plants (OM Code). Mandatory Appendix I,
310(c), requires that, "The Owner, based upon system and valve design basics or technical specification, shall establish and document acceptance criteria for tests required by this Appendix. - Please provide the valve design document and basics such as consideration of simmering, seat leakages, and reliability for establishing low set-point pressure tolerances including the manufacture recommended low set-point pressure limits for the main steam safety/relief valves PSV141F0 I 3A, B, C, D, F, F. G,
, NI N, P, R. and S.
PPE, :RESPONSE:
PPE_ Susquehanna, I.,LC has requested a revision to Unit I and Unit 2 Technical Specification Surveillance Requirement (SR) 3.4.3.1 to change the as-found set pressure acceptance criteria tolerance from -3%, +3% of the main steam safety/relief valve (MSRV) safety setpoint to -5%,
+3% of the MSRV safety sctpoint. The SR 3.4.3.1 revision request does not change the as-left setpoint tolerance of -1%, i-1 (1'6 of the MSRV safety setpoint.
Crosby Valve and Gage Company Procedure 1-11069, "Instruction Manual for Crosby Style 6xRx10 I1B-65-BP Safety Relief Valve tOr Main Steam Service" (10114563) discusses performance in Section 3. Step 3.1.1.4, as amended by PPL WIEN 1 -18, states the following:
"Setpoint repeatability for on line service should he within 3%, -3% of nameplate set pressure.
However, the low limit of the setpoint tolerance may be extended to 1067 pstg if all other valve functional requirements are met."
..c.'quii...!,steci SR 143.1. revision will lower the minimum :MSP'V as,-.10iind setpoint. acceptance
,,till ves from i 140 1.7.'i,sig to stirI be,g,,,,reaUti-than th..c glantifraCillrtir'S
10:01 SdreciTti prCSSUP:
Attachrnen1 1 to PLA-6750 Pa
1176 e.ri teria, and a suntmar f ta.k. evaluations
- valu_at ons ofthe causes and generic concerns of
al \\ICS identified in R.,11-1 that.failed to meet
v set point Pressure limits.
PM.. RESPONSE:
The I 0-year main steam sok /relief valve (MSRV) test history (2002 2011) is listed below.
There were no MSRV test failures due to exceeding. the maximum tolerance of -13% of the safety setpoint. There were 14 failures due to the initial as-lbund setpoint being below the minimum tolerance of -3';'/0 of the safety se point. Twelve (12) of the 14 failures were in the r
of -3%
to -.5% of the safety setpoint.
MSRV S/N Date Tested Set Press
,s11)
As-found lift 1 ressure
1st!)
Deviation (%)
N63790-00-0019 3/24/02 1195 1185
-0.84 4/22/09 1195 1155
-3.35
-0020 3/25/02 1205 1178
-2.24 4/22/09 1205 1165
-3.32
-0021 3/21/08 1195 1177
-1.51 4/15/11 1195 1144
-4.27
-0022 3/24/02 1205 1199
-0.50 4/29/09 1205 1215
+0.83
-0023 3/30/03 1205 1185
-1.66 3/22/08 1205 1207
+0.17
-0024 3/28/03 1205 1196
-0.75 3/21/10 1205 1196
-0.75
-0025 3/30/03 1205 1169
-2.99 3/21/08 1205 1137
-5.64
-0026 3/31/03 1195 1174 Y
3/23/10 1195 1207
-00,7 3/24/02 1195 1162 4/22/09 1195 1204 0
' v 3/16/06 1195 1190
-0.42 4/25/11 1195 1200
+0.42 0 i'
1
t i 195 1188
-0.59
`:3/it,
s 1208
+1.09
tt ichm ent 1 to PI,A-6750 Page 3 o C 6 MS12NI S/N Date Tested Set Press (psig)
As-fo nd lilt:
pressure (psig)
Deviation (%)
-0030 3/16/07 1195 1190
-0.42
-0031 3/31/03 1195 1180
-1.26 3/17/06 1195 1166
-2.43 4/15/11 1195 1174
-1.76
-0032 3/25/04 1205 1176
-2.41 3/13/10 1205 1224
+1.58
-0033 3/31/03 1195 1190
-0.42 3/21/10 1195 1225
+2.51
-0034 3/11/05 1195 1188
-0.59 3/22/10 1195 1188
-0.59
-0081 3/15/06 1195 1154
-3.43 4/15/11 1195 1148
-3.93
-0082 3/31/03 1205 1200
-0.41 3/21/08 1205 1159
-3.82
-0083 3/28/03 1175 1161
-1.19 3/20/10 1175 1175 0
-0084 3/28/04 1195 1184
-0.92 4/26/11 1195 1193
-0.17
-0085 3/9/05 1175 1195
+1.70 4/23/09 1175 1123
-4.42
-0086 3/28/04 1175 1191
(.1.36 5/2/11 1175 1161
-1.19
-0087 3/17/06 1205 1191 4/16/11 1205 1189
-0088 3/22/08 1205 1205
-0089 3/16/06 1205 12, n 1
to PI...A-6750 Pat e 4of 6 IN IS R 'V S/N Date Tested Set Press (prig) 1205 As-fo
I lift pressure (psag)
1195 Deviation (%)
-0.83
-0090 3/77/04 4/20/11 1205 1178
-0091 3/29/04 1205 1193
-1.00 4/23/09 1205 1187
-1.49
-0092 3/30/04 1195 1200
+0.42 4/22/11 1195 1208
+1.09
-0093 3/10/05 1205 1154
-4.23 3/20/10 1205 1153
-4.32
-0094 3/26/04 1205 1174
-2.57 4/25/11 1205 1179
-2.16
-0095 3/11/05 1205 1199
-0.50 3/19/10 1205 1173
-2.66
-0096 3/9/05 1205 1194
-0.91 3/23/10 1205 1160
-3.73
-0112 3/26/02 1205 1220
+1.24 3/15/07 1205 1209
+0.33
-0113 3/21/08 1175 1164
-0.94
-0128 3/23/02 1175 1193 3/15/07 1175 1184
-0129 3/16/07 1205 1199
-0. '59
-0130 3/24/02 1205 1184
.114 3/15/07 1205 1145
-4.98
-0131 3/15/06 1205 1215
+0. 83 4/25/11 1205 1148
-4.73
-0132 3/10/05 1195 1134
-5.10 3/14/10 1195 1 1 J\\0 1 ?"6
-0133
?
1
^f 1 208
[09 3/14/0"'
1 90 0.42 to PLA- )750 Page 5 016 Tfiere were no MSR.V setpoint test failures from 2002 2t)05..1-7rom. 2005 2009, cause eVaillatIMS were not performed for.MSR.Vs that litile,d because they were below the minimum tolerance of -3% of the safety setpoint. This is documented in non-cited violations 05000387 &
05000388/2009003-01 and CR 1.177479. CR. 1177479 stated that the cause of the 9 M.SRV test failures that occurred.from 2005 2009 is setpoint variance that is inherent to the Crosby 6\\Rx 10 relief valve design.
In 2010, valves -0093 and -00% failed their setpoint tests due to as-found initial test results that were below -3% of the safety setpoint. CR 1247012 determined that the -0093 valve failed due to setpoint variance that is inherent to the Crosby 6x.Rx10 relief valve design. The -0096 test failure was attributed to minor wecpage through the seat, which. is also a known industry cause of setpoint drift in the lower direction.
In 2011, valves -0021. -0081 and -0131 failed their setpoint tests due to as-found initial test results that were below -3°/0 of the safety setpoint. CR 1399810 determined that the -0081 and -
0131 valves failed due to setpoint variance that is inherent to the Crosby 6xRx10 relief valve design. The -0021 test failure was attributed to minor weepage through the seat, which is also a known iiidustry cause of setpoint drift in the lower direction.
RA1-3:
On page 8 cif the submittal referenced above. ;PPI,'s submittal PIA-6642, dated November 10, 22101, PN, states that no additional valves will be tested if the as-fOund set point is below the nameplate set point. This appears to conflict with 1-1330(c)(1), which requires that additional valves be tested if the specified set-point pressure tolerance limits including the lower' set-point.
pressures are not Inet D ut*j ng conference ca ll. on J une 8, 2011, pm._ cited relief request RR-02 for basis not complying with [1330(4 RR-02 was submitted to the NRC the review in a letter fi.c.),, -1) ma:., 24 2004,,
,e1 ter' WaS t,o NI R(7,
IR R-02
- ON1 The N.:
T.WO t y: tostcd
th
. to P1,A-6750 Page 6 of 6 valve at Susquehanna SFS (1175 psig), the low limit of the setpoint tolerance would be
and 1-or the highest pressure setpoint valve (1205 psig) the low limit would he Based on the above, the pressure setpoint would have to exceed -9';';') of name plate rating to be outside the acceptable range specified bA,,, the vendor fbr valve peribrmance..(,he lower pressure setpoint tolerance limit of
was exceeded 3 times in 308 tests perfOrmed at. Susquehanna since 1985. The lowest pressure setpoint observed was -5.64 1N). Based on the manufacturer's procedure, this pressure setpoint is well with in the valve's acceptable range of performance.
The lower tolerance limit was chosen conservatively. A lower setpoint is conservative in that the MSRV would open sooner to provide over pressure protection. Therefore, testing of additional valves would not provide any increase in quality or safety,
ATTACHMENT 2 TO PLA-6750 Excerpt from Crosby Valve and Gage Compa Procedure 1 - 11069
Attachment to PLA-6750 Page1of I CROSBY CROSBY VALVE & GAGE COMPANY 0
WRENTHAM, MASS
. Performance 0
3.1 Safety Valve Mode of Operation
3 3.1.1 Set Pressure 3.1.1.1 The specified set pressure for each valve is stamped on the valve nameplate.
3.1.1.2 All valves are Factory set to a tolerance of +0, -2% of name-plate set pressure.
3.1.1.3 All valves are Factory set for a thermally stabilized ambient temperature of 135°F.
1-37.
/ micAl et g 3.1.1.4 Set point e eatability for on line service should be within a tolerance of e+.1', -32 of nameplate set pressure. However-the low limit of the set point tolerance may be extended to 1067 psi if all other valve functional requirements are met.
3.1.1.5 The nozzle ring is Factory set to provide a clean "popping" action. Field adjustment should not be required.
3.1.2 Blowdown 3.1.2.1 All valves are Factory adjusted to blowdown within the range of 22 to 11% of the actual popping pressure that is within i3'/-32 of the nameplate value.
/ /MCAT t°1 3.1.2.2 The blowdown range of 2% to 117. applies for all back pressure values applicable to a specific back pressure range per plant discharge line configuration.
3.1.2.3 Whenever a part critical to the lifted position force balance is replaced, the valve must be retested for blowdown. These parts are the adjusting ring (Pc. 64), the disc ring-disc holder-bellows assembly (Pcs. 5, 6 and 7), the eductor (Pc.
- 11) and the spring (Pc. 24).
3.1.2.4 The adjusting ring is Factory set to provide the correct blow-down range. Field adjustment should not be required. If adjustment is required due to part replacement, valve set point change or plant modifications, refer to Section 6.3 of of this manual.
1-11069 PROCEDURE NO.
REV.
SHEET 17 OF 104