ML20210T562
| ML20210T562 | |
| Person / Time | |
|---|---|
| Site: | Mcguire |
| Issue date: | 09/30/1986 |
| From: | Johansen R, Marguis D, Morales S DUKE POWER CO. |
| To: | |
| Shared Package | |
| ML20210T541 | List: |
| References | |
| NUDOCS 8610090075 | |
| Download: ML20210T562 (20) | |
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3 DUKE POWER COMPANY MCGUIRE NUCLEAR STATION UNIT 2 ADDENDUM TO THE REACTOR CONTAINMENT BUILDING INTEGRATED LEAK RATE TEST CONDUCTED MAY 20 - MAY 26, 1986 INVESTIGATION OF CONTAINMENT DEVIATIONS FROM
- "AS FOUND" CONDITIONS l
[ //] A Add //
Prepared By: _xzaw~ L //w
' Kephen'K. Morales Associate Engineer 1
Reviewed By: - ~ , T 9 ^ o---
R.A.Johpen Test Engineer Approved By: OhA u D.S.Marqu\s Performance En 'neer 8610090075 860930 4 PDR ADOCK 05000370 P PDR
x Unit 2 Integrated Leak Rate Test Addendum SYNOPSIS f '
An investigation was performed to assess the condition of the McGuire Unit 2 containment prior to maintenance during the EOC-2 outage. The results of this i
investigation, along with the total containment leak rate measured by the Integrated Leak Rate Test performed in May 1986, were used to calculated the "as found" containment leakage.
Containment integrity requirements at McGuire define the maximum leak rate (L )
A as 0.30% of the containment air mass per day. This converts to 135,920 SCCM.
A total leak rate savings of 96,112 SCCM was determined by the investigation.
The total containment leak rate measured by the ILRT, (LAM) was 0.08371% mass per day, or 37,930 SCCM. The total improvements to containment integrity made during the outage (e.g., savings) plus LAM equals 134,042 SCCM, which represents the "as found" leak rate.
Comparing the conservatively calculated "as found" containment leak rate to L A
yields the following conclusions:
A challenge of the "as found" containment by a design basis accident would not have resulted in leakage exceeding L *A The present containment integrity program is adequate for maintaining acceptable leak rates.
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EVALUATION The first surveillance Integrated Leak Rate Test (ILRT) was performed for McGuire Unit 2 during the EOC-2 outage. Prior to the outage, the need to pretest containment isolation valves before maintenance to assess ILRT impact
. had not been identified. Thus, a review of penetration maintenance histories was performed to quantify the leak rate improvements (or " savings") made prior to the ILRT. The leak rate measured during the ILRT-plus savings gives the "as t found" total containment leak rate.
The first step in determining the "as-found" containment. leak rate was to identify all outage maintenance on penetration components performed prior to the ILRT. No work was identified for any electrical penetration. The results of this survey for mechanical penetrations are given in Table 1.
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All the work identified was then evaluated for possible impact on component
- leak rate. Thirty-nine penetrations were subject to at least one work request
- (WR). Of these, fifteen penetrations had WRs which involved only electrical circuitry and could not have improved the valves' leakage. On twenty-four penetrations work was done which could produce leakage savings.
In order to calculate the impact of work on a particular penetration, the minimum thru-path leakage before and after the work were compared. For penetrations with work performed on only one side and no pretest data, the leak rate of the undisturbed side was conservatively assumed to be the "before" thru path leak rate. If the post-maintenance thru-path leak rate was less than this value, the difference was reported as savings. If this approach was I
applied to a penetration whose originally tighter side had been worked on, the calculated savings would be greater than actual, a conservative error.
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. _ . - . -, _ . ~ _ . _ . _ , , - . - . , . . - - . _ . _ - - . . _ . . - . . . , - - , . ._ - - .. , . _ , , - - - _ .
. )
Twenty-one penetrations either had only one containment isolation valve worked on or adequate pretest data existed so that an "as-found" minimum pathway leakage could be determined. Table 2 shows the leakage savings determined for each of these twenty-one penetrations as well as the airlock and equipment hatch data. Three penetrations had work done on both sides of containment.
Each of these penetrations is analyzed in the Appendix.
, The savings calculated for all penetrations is 96,112 SCCM, with one penetration contributing approximately 98% of the total. Leakage measured during the ILRT is equivalent to 37,930 SCCM. Summing the calculated savings and the ILRT leak rate gives a conservative "as found" total containment leak rate of 134,042 SCCM.
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, Following all outage maintenance, the total containment leak rate for Type B i
and C penetrations was calculated to be 4192 SCCM. A breakdown of these "as left" values is given by Table 3.
Comparing the above values to the "as found" acceptance criteria of-135,290 SCCMA(L ) and the Type B and C penetration surveillance limit of 81,552 SCCM (0.6AL ) dem nstrates the following:
degradation of the containment leak rate during the surveillance
- interval did not cause limits to be exceeded.
the "as left" leak rate is well below surveillance limits, allowing
- ample margin for degradation during the following surveillance interval.
I 3
- )
Mzchanical Penstrstion Work R: quest Survey
, Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument' 3/15+5/23/86 Affected?
e H118 2HN5PT5070 86695 N ZHNSPT5390 66024 N 86695 N 2MNSPT5520 66024 N 86695 N 2MNSPT5530 93813 Y M118A 2MMIMV6980 951122 Y 2M1INV7010 -None N/A M118B 2MMINV6990 None N/A 2MMINV7020 None N/A M118C 2MMIMV7000 None N/A 2MMIMV7030 None N/A M119 2MVPNV0015 None N/A 4
2MVPNV0016 None N/A 2MVPPX5240 None N/A M138 2MVPMV0019 None N/A 2MVPMV0020 None N/A 2MVPPX5600 None N/A l
C152 2IACV5350 None N/A 1 2IASV5160 None N/A M212 2MNCEV0540 93879 Y 2MNCEV0530 None N/A t
M213 2MVPNV0017 None N/A 2MVPMV0018 None N/A 2MVPPX5250 None N/A 4
A MIchtnical Penctratica Work R: quest Survzy Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
11215 ZI-IVBHVGG49 93632 N 2MVBMV0050 None N/A 2MVBMV0051 None N/A M216 2MNCMV0057 None N/A 2MNCMV0056 None N/A 2MNCMV0120 None N/A M219 2MVSMV0012 93632 N 2HVSMV0013 None' N/A 2MVSMV0025 None N/A M220 2MVIMV0129 93632 N 2MVIMV0040 None N/A 2MVIMV0284 None N/A M221 2MWLM"9321 None N/A 2MWLMV0322 None N/A 2MWLMV0385 None N/A M235 2MNMMV0003 None N/A 2MNMMV0006 None N/A 2MNMMV0007 93632 N 2MNMMV0420 None N/A M239 2MNSPT5060 86695 N 2MNSPT5510 86695 N 2MNSPT5380 66024 N 86695 N M239A 2MMISV6870 65525 N
, 2MMISV6890 None N/A l
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. T M:chtnical P2nstrctica Work Rzquest Survzy Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M239B 2MMISV6880 65525 N 2MMISV6900 None N/A M239C 2MMISV6910 65528 N 86710 Y 2MMISV6930 None N/A M239D 2MMISV6920 65528 N 86709 Y 2MMISV6940 None N/A i
M240 2MRVMV0032 86708 Y 2MRVMV0316 None N/A 2MRVMV0033 None N/A 2MRVMV0130 None N/A M243 2MVQMV0001 None N/A 2MVQMV0002 None N/A M259 2MNBMV0260 None N/A 2MNBMV0261 None N/A 2MNBMV0262 86707 Y M279 2MRVMV0076 None N/A 2MRVMV0077 None N/A 2MRVMV0126 None N/A 2MRVMV0317 None N/A 6
Mech:nical Prnstraticn Work Rzquast Survey Tcbic 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M280 2MNMRV0069 None N/A 2MNMMV0072 None N/A 2MNMMV0075 None N/A 2MNMMV0078 None N/A 2MNMNV0081 None N/A 2MNMHV0082 None N/A M307 ZMRNMV0252 None N/A 2MRNMV0253 None N/A 2MRNMV0451 None N/A 2MRNMV0886 None N/A M309 2MNMMV0022 93865 N 2MNMMV0025 93865 N 2MNMMV0026 93632 N 93866 N 2MNMMV0421 None N/A M313 2MNSPT5050 86695 N 2MNSPT5500 66024 N 86695 N 2MNSLP5370 66024 N 86695 N M315 2MRNMV0276 None N/A 2MRNMV0277 None N/A 2MRNMV0452 None N/A 2MRNMV0881 None N/A M317 2MVIMV0124 None N/A 2MVIMV0150 93632 N 2MVIMV0378 None N/A 7
3 M2chinical Panstratica Wsrk Rzquest Survty Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M320 2MKCMV0279 None N/A 2MKCMV0424 048715 Y 93833 N 2MCKMV0425 048697 Y 93833 N M321 2MNIMV0095 65732 N 93632 N 93836 N 2MNIMV0096 65732 N 93632 N 93836 N 2MNINV0120 65732 N 93632 N 93836 N 122423 Y 2MNIMV0436 None N/A 2MNIMV0046 None N/A M322 2MKCMV0047 86725 Y 2MKCMV0429 93833 N 2MKCMV0430 93833 N M323A 2MMISV5580 None N/A 2MMISV5581 65525 N M323B 2MMISV5582 None N/A 2MMISV5583 65525 N M325 2MVXVM0030 None N/A 2MVXMV0020 None N/A C
Mechtnical Panstratica Wark R:qurst Surysy Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M326 2MNCMV0141 None N/A ZMNCMV0142 None N/A 2MNCMV0261 None N/A 2MNCMV0154 None N/A M327 2MKCMV0338 048698 Y 93833 N ZMKCMV0339 None N/A 2MKCffV0340 None N/A M330 2MNIMV0048 None N/A 2MNIMV0047 65732 N 93836 N 2MNINV0107 None N/A M331 2MVENV0010 None N/A 2MVEMV0011 None N/A 2MVEMV0012 None N/A M337 2MYMMV0115 None N/A 2MYMMV0116 None N/A 2MYMMV0124 None N/A M342 2MNVMV0849 None N/A 2MNVMV1001 None N/A 2MNVMV1002 None N/A l
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M;chenical Panztratien Work Rsqunet Surv y Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M348 2MNIMV0264 65732 N 93836 N 2MNIMV0265 None N/A 2MNINV0266 65732 N 2MNIMV0267 65732 N 122319 Y 2MNIMV0466 None N/A M353 IMRFMV0932 None N/A 1MRFMV0833 None N/A 1MRFMV0834 None N/A M355 2MKCMV0332 048733 Y 2MKCMV0333 None N/A 2MCKMV0280 None N/A M356 2MWEMV0013 None N/A 2MWEMV0014 None N/A 2MWEMV0023 None N/A M357 2MVPMV0006 None N/A 2HVPHV0007 None N/A 2MVPPX5200 None N/A M358 LdihMVC011 None N/A 2MFWMV0012 None N/A 2MFWMV0013 None N/A 2MFWMV0063 None N/A M359 2MVIMV0160 93632- N 2MVIMV0161 None N/A 2MVIMV0282 None N/A 10 l
MIchtnical Penztration Work R:quent Survsy
, Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M360 2MWLMV0039 None N/A 2MWLMV0041 86703 Y 2MWLMV0389 None N/A M361 2MNCMV0195 048704 Y 2MNCMV0196 054316 Y 2MNCMV0259 None N/A M367 2MVPMV0001 None N/A 2MVPMV0002 None N/A l 2MVPPX5180 None N/A M368 2MVPMV0010 86837 Y 2MVPMV0011 86898 Y 2MVPPX5220 None N/A M372 2MNFMV0233 None N/A 2MNFMV0234 None N/A 2MNFMV1051 121985 Y M373 2MNFMV0228 None N/A 2MNFMV0229 None N/A 2MNFMV0231 048735 Y 2MNFMV0959 None N/A M374 2MWLMV0064 None N/A 2MWLMV0065 None N/A 2MWLRV0264 None N/A 2MWLMV0390 None N/A 2MWLMV0802 None ,
N/A l
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Mechrnical PInttratien Wark R:quist Survzy-Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M375 2MWLMV0001 121987 Y 2MWDfV0002 121988 Y 2MWLMV0024 None N/A 2MWLMV0816 None N/A M376 2MKCMV0322 None N/A 2MKCMV0320 048734 Y 2MKCMV0321 None N/A M377 2MFWMV0004 None N/A 2MFWMV0005 None N/A 2MFWMV0030 None N/A M378 2MVXMV0031 None N/A 2MVXMV0033 None N/A 2MVXMV0034 None N/A M384 2MVQMV0005 None- N/A 2MVQMV0006 None N/A 2MVQMV0011 None N/A M385 2MRVMV0079 None N/A 2MRVMV0080 None N/A 2MRVMV0139 None N/A 2MRVMV0365 None N/A M386 2MVIMV0148 93632 N 2MVINV0149 None N/A 2MVINV0362 054317 Y 2MVINV0376 None N/A 12
Mechinical PInettstion Work R:qu:st Survsy
, Table 1 Seat Isolation Valve WR No. Possibly Penetration or Instrument 3/15+5/23/86 Affected?
M390 2MRVMV0101 None N/A ZMRVMV0102 .None N/A 2MRVMV0366 None N/A 2MRVMV0140 None h/A C392 2IAECV5340 None N/A 2IAESV5080 None N/A M394 Flanged None N/A M402A 2MNSSV5550 65824 N 2MNSSV5551 65824 N M402 2MNSPT5040 86695 N 2MNSPT5360 None N/A 2MNSPT5490 66024 N 86695 N MNSPT5540 93813 Y M454 2MVPMV0012 86842 Y 2MVPMV0013 86842 Y 2MVPPX5230 None N/A M456 2MVPNV0008 86842 Y 2MVPMV0009 86842 Y 2MVPPX5120 None N/A i
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Lesksgs Savings Dztermination Table 2 Minimum Path Leakage Flow Savings Penetration "As Found" "As Left" SCCM M118 20 20 0 M118A 20 20 0 M212 2 2- 0
_; M239C 48 20 28 M239D 20- 20 0 M240 22 22 0 M259 20 20 0 M321 22 14 8 4 M322 20 20 0 M327 85 20 65 i M348 50 50 0 M355 20 20 0-M360 7 7 0 M368 66 1 65 M372 2 2 0 M373 4 2 2 M376 65 20 45 M386 2 2 0 M402 20 20 0 M454 31 17 14 M456 44 235 0 SUBTOTAL 227 Upper Airlock 1450 972 478 Lower Airlock 1085 232 853
! Equipment Hatch 4 89 0 1
4 AIRLOCK SUBTOTAL 1331 M320 0 i
M361 0 M375 94524 TOTAL SAVINGS 96112 14
_ . . - . . - ~ . - . . . _ _ _ _ _._ ._ -..,_ _ _ ._ -.._. _ _ _ . ~ . - - , _ _ _ - . - _ . - . _ _ _ . _
l Table 3 Type B and C Penetration "As Left" Leak Rates Test Rate (SCCM) 4 Electrical Penetrations (PT/2/A/4200/01B 45 Non-Bypass Leakage (PT/2/A/4200/01P) 132 i Bypass Leakage (from Er. closure 13.2) 2811 f Upper Personnel Airlock (PT/2/A/4200/01E) 972 Lower Personnel Airlock (PT/2/A/4200/0'F) 232 Total (Type B and C Leakage) 4192 a
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._ . . . - - . . _ _ . , . _ _ . _ _ _ - _ _ _ _ - _ - _ . _ - - _ . _ . _ _ _ . , , . . _ . _ _ _ _ _ _ _ _ . , _ . . . _ . , _ _ - _ . _ ~ _ _ _ - , - ,
Appendix Analysis of Three Penetrations with Work Done on Both Sides of Containment Three penetrations M320, M361 and M375 had work done on both sides of containment. Below, each one's work.and history are discussed to assess its
' impact to this outage's ILRT.
M320 is a penetration for the 8-inch KC (component cooling) return line.
The Aux Building side isolation valve is hC325A, an 8-inch butterfly valve with a Limitorque operator. The containment side isolation valve is KC424B, also a butterfly valve with a Limitorque operator; parallel to KC424B is a 1-inch bypass.line with check valve KC279.
Preventive maintenance (PM) w<s performed on the Limitorque operators of KC424B and KC425A. The PM entails inspection and lubrication as needed for the Equipment Qualification Program. These valves close to a travel limit switch with a torque limit backup. As long as the travel limit switches were not adjusted any improvement in valve torque loading will not improve the valve seat. The limit switch was adjusted on KC424B but not on KC425A. Neither valve had to be lubricated. Thus the seat of KC425A was not improved. Leakage for both valves has been below measurable limits for the past two surveillances. LLRT performed after this maintenance yielded leak rates of 20 scem for KC425A and 220 seem for KC424B. Based on a consistent history for KC425A, it is reasonable to assume an "as found" minimum path leakage of 20 scem with zero savings.
M361 is a penetration for the 2-inch NC lubrication oil supply line. The Aux Building side isolation valve is NC195B, a 2-inch globe valve with a Limitorque operator. The containment side isolation valve is NC196A, a similar valve and operator. A 3/4-inch bypass line with check valve NC259 is in parallel with NC196A.
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Preventive maintenance was performed'on the Limitorque operators of NC195B and NC196A. The PM entails. inspection and lubrication as needed for the Equipment Qualification Program. These valves close to a torque limit. Lubrication could allow the actuator to have more torque for making the seat. .However, neither valve needed to be lubricated; therefore, the seats were not improved. Leakage for both valves has been below measurable limits'for the past
~
two surveillances. The LLRT history shows that each valve has leaked below detectable amount every test. It is reasonable to assume for this penetration an "as found" minimum path leakage of 20 scem with zero savings.
M375 is a penetration'for the 3-inch WL line which discharges from the reactor coolant train tank. The Aux Building side isolation valve is WLIB, a 3-inch diaphragm valve with a Rotork operator, as is the.
containment side isolation valve WL2A. A 1/2-inch bypass line with check valve WL24 bypasses WL2A. A 1-inch high point vent with WL816, a Kerotest valve, protrudes from the Aux Building side of the penetration.
WLIB and WL2A were determined to be leaking while troubleshooting for excess reactor coolant leakage. LER 360-86-03 describes how this was done. Work requests were written to repair the valves. No prework leakage was measured.
The reactor coolant leakage calculation yielded 1.5-2 gpm in unidentified leakage. Assume 2 gpm was leaking through M375.
The maintenance on WLIB uncovered a broken shaft on the Rotork limit switches which would either seat the valve or stop it at an intermediate position. Assume the valve was stopped in the open position.
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The discharge pressure of the reactor coolant drain tank (NCDT) pumps was 125 psig. These pumps were on at the time, recircing the NCDT. To account for piping losses, assume the pressure upstream of WL2A was 110 psig. This line dumps into the reator water holdup tank which is near atmospheric pressure. To
- account for piping losses assume pressure downstream of WL2A was 10 psig.
Assume the leaking WL2A simulates an orifice in the line. Based on these assumptions an equivalent type A leakage can be determined for air. Volumetric flow of water through an orifice is:
l d2 AP y 9H20(v 1/t) = C1 ,
where:
C1 = c nstant to make units balance d = orifice diameter D = pipe diameter APy = pressure drop across the orifice = 100 psi p1 = density of the water 1 gm/cc For air or any other gas the equation is:
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Yd 3p 8
q gas (vol/t) = C 1 i 1 - (d/D) p g
] where:
Y = a compressibility factor p = density of the gas 0.00106 gm/cc (at 100F, saturated, and 14.7 psi which is the downstream pressure)
AP = 15 psi for Type A test conditions g
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e Dividing these two equations:
9 Y VAP p 8as , 1 9H2O
/APyp '
Compressibility factors range from .85 to 1.0.
For conservatism assume Y = 1.0.
Thus:
q(air)ILRT
= 11.90 q(water)1eak Therefore:
q(air)ILRT = 11.90 x 2 gpm
= 11.90 x 7570. scem
= 90051. scem For uncertainty 5% will be added to this number. Thus, the equivalent leakage of air through penetration M375 was 94554 secm. The retest LLRT yielded a leakage of 30 scem. There was a savings of 94524. seem on M375.
REFERENCES
- 1. LER 370-86-03
- 2. R.W. Miller, " Flow Measurement Engineering Handbook", McGraw-Hill Book Company, 1983.
- 3. C.O. Bennett and J.E. Myer, " Momentum, Heat, and Mass Transfer", 2nd Ed.,
McGraw-Hill Book Company, 1974.
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