ML13283A014
| ML13283A014 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 10/01/2013 |
| From: | Capps S Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| MC-SRP-ND-01, TAC MF1166, TAC MF1167 | |
| Download: ML13283A014 (7) | |
Text
DUKE
`ý`ENERGY Steven D. Capps Vice President McGuire Nudear Statim~
Duke &m MIGO1VP 1 12700 Hagers Ferry RPiad Huntersville, NC 28078 a: 980.875.4805 fý 980.875.4809 Stee.Capps@duke-ene m.cm October 1, 2013 10 CFR 50.55a U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
SUBJECT:
Duke Energy Carolinas, LLC (Duke Energy)
McGuire Nuclear Station Units 1 and 2 Docket Numbers 50-369 and 50-370 Relief Request MC-SRP-ND-01 (TAC NOS. MF1166 and MF1167)
By letter dated February 27, 2013, Duke Energy submitted the Inservice Testing Program for the Fourth Ten-Year Interval at the McGuire Nuclear Station. Included in that submittal is proposed Relief Request (RR) MC-SRP-ND-01 for the Nuclear Regulatory Commission's (NRC) review and approval.
By letter dated August 19, 2013, the NRC issued a Request for Additional Information (RAI) regarding this RR. Enclosed is Duke Energy's response to this RAI. Also enclosed is revised RR MC-SRP-ND-01.
If you have any questions or require additional information, please contact P. T. Vu of Regulatory Affairs at (980) 875-4302.
Sincerely, Steven D.p Enclosure A
DL4 112 www.duke-energy.com
A U. S. Nuclear Regulatory Commission October 1, 2013 Page 2 xc:
Victor McCree, Region Il Administrator U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257 Jason Paige, Project Manager U. S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 0-8 G9A Rockville, MD 20852-2738 John Zeiler NRC Senior Resident Inspector McGuire Nuclear Station
MCGUIRE NUCLEAR STATION ENCLOSURE RELIEF REQUEST MC-SRP-ND-01 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION
4-.
U. S. Nuclear Regulatory Commission Enclosure October 1, 2013 Page 1 of 1 RAI MC-SRP-ND-01-1:
Relief request MC-SRP-ND-01, under "Alternate Testing," contains a heading "Group A /
Comprehensive Tests." Is the licensee requesting relief for Group A tests, Comprehensive Tests, or both? The licensee states in relief request MC-SRP-ND-01, page 2, that "the instrumentation used to measure suction and discharge pressure is more accurate than ASME Code requirements (0.5% vs. 2%)." This statement is true for the accuracy requirements for Group A tests in ASME OM Code Table ISTB-351 0-1. The licensee also states that the code allowable actual instrument error is "6% (2*690/230)." This is also true for Group A tests as per ASME OM Code Table ISTB-3510-1. However, for comprehensive tests, ASME OM Code Table ISTB-3510-1 requires an accuracy of 0.5%. If a gauge that meets the three times the reference value criteria is used, the code allowable reading error is therefore 0.5%
- 3 = 1.5%
for comprehensive tests.
The licensee states that "the actual reading error at test pressure due to the process instrument is 2.2%." If the licensee is seeking relief for comprehensive testing, please justify how the instrumentation provides acceptable measurement accuracy as an alternative to the requirements listed in ASME OM Code Table ISTB-3510-1 for comprehensive tests.
Response
The licensee is requesting relief for Group A tests only. The relief request is revised as attached to remove the application to Comprehensive Tests.
RAI MC-SRP-ND-01-2:
Relief request MC-SRP-ND-01, page 1, states that there are two suction pressure gauges installed with ranges of 0-60 psig and 0-600 psig. Relief request MC-SRP-ND-01, page 2, states that the typical values for ND (residual heat removal) suction range from 48-81 psig.
Since the 0-60 psig gauge cannot read values exceeding 60 psig, the 0-600 psig gauge must be relied upon for suction pressure measurements ranging from 60-81 psig. For this range, the most conservative reading error is therefore 0.5% * (600/60) = 5%. If suction pressure is obtained from the 0-600 gauge only, the most conservative reading error would be 0.5% * (600/48) = 6.25%, which is greater than the reading error that the licensee states is acceptable by code requirements (6%). Please justify how the test procedures and instrumentation implemented will ensure that an acceptable level of accuracy is achieved for the measurement of suction pressure.
Response
The lower range (0-60 psig) suction gauge is used for pressure values within its range. The higher range (0-600 psig) suction gauge is used for pressure values exceeding the lower range values. If a 0-180 psig gauge was used with 2% accuracy, the reading error would be 6% (2%
- 180/60). Using the installed suction pressure gauge, the actual reading error for pressure values as low as 60 psig would be 5% (0.5%
- 600/60). The relief request is revised accordingly as attached to explain how the test procedures and suction pressure instrumentation implemented ensures that an acceptable level of accuracy is achieved.
A MCGUIRE NUCLEAR STATION REVISED RELIEF REQUEST MC-SRP-ND-01
McGuire Nuclear Station - Unit 1 McGuire Nuclear Station - Unit 2 Specific Pump Relief Request RELIEF REQUEST:
MC-SRP-ND-01 PUMPS:
1NDPU0001, 1A Residual Heat Removal Pump 1NDPU0002, 1B Residual Heat Removal Pump 2NDPU0001, 2A Residual Heat Removal Pump 2NDPU0002, 2B Residual Heat Removal Pump TEST REQUIREMENT:
BASIS FOR RELIEF:
ALTERNATE TESTING:
OMb-2006, ISTB-3500 specifies the range of each instrument shall be three times the reference value or less.
Range requirements will be waived for the tests. The purpose of the quarterly test is to verify Technical Specification requirements are met and to obtain vibration data for trending. The instrumentation used for the quarterly residual heat removal pump test will meet accuracy requirements for assuring residual heat removal pump operability per Technical Specifications.
The residual heat removal pumps will be tested according to the following program, which is consistent with NRC Generic Letter 89-04.
These pumps have process instrumentation installed such that there are two suction pressure gauges (0-60 psig and 0-600 psig),
and one discharge pressure gauge (0-1000 psig). Each has 0.5%
accuracy. This is done to provide accurate pressure indication in either the recirculation or the heat removal condition of operation.
As such, there are times when the 3 times the reference range requirements cannot be met.
Group A Test The residual heat removal pumps will be tested quarterly to verify Technical Specifications are met. The test measures differential pressure data. The differential pressure will be trended.
The instrumentation range requirements of OMb-2006, ISTB-3500 will be waived. Since the instrumentation used to measure suction and discharge pressure is more accurate than ASME Code requirements (0.5% vs. 2%), using the process instrument for this test will yield results within the overall accuracy requirements of the ASME Code and will meet applicable accuracy requirements for the determination of operability per Technical Specifications.
10/01/13 Rev. 28a Section 5.2 MC-SRP-ND-01 Page 1 of2
A McGuire Nuclear Station - Unit 1 McGuire Nuclear Station - Unit 2 RELIEF REQUEST:
MC-SRP-ND-01 (Continued)
Typical values for ND discharge pressures are in the 220-270 psig range. Therefore, the process range for discharge pressure gauge (0-1000 psig) will not meet the three times criteria. The accuracy of these process instruments (0.5%) is better than the requirements specified in Table ISTB-3510-1 for instrument accuracy (2%). The actual reading error at test pressure due to the process instrument is 2.3% (0.5%
- 1000/220) for discharge pressure at the low end of this range. If a 0-660 psig gauge was used with 2% accuracy, the reading error would be 6%
(2%
- 660/220).
Typical values for ND suction pressure in mini-flow are 46-81 psig. The lower range (0-60 psig) suction gauge is used for values within its range. The higher range (0-600 psig) suction gauge is used for pressure values exceeding the lower range values. Therefore, the process range for higher range suction pressure gauge (0-600 psig) will not meet the three times criteria.
The accuracy of these process instruments (0.5%) is better than the requirements specified in Table ISTB-3510-1 for instrument accuracy (2%). The actual reading error at test pressure due to the process instrument is 5% (0.5%
- 600/60) for suction pressure at the low end of this range. If a 0-180 psig gauge was used with 2% accuracy, the reading error would be 6% (2%
- 180/60).
Using the process instruments for suction and discharge pressure as described above does not degrade the quality of the test and meets the intent of the instrumentation requirements of the ASME Code.
10/01/13 MC-SRP-ND-01 Rev. 28a Page 2 of 2 Section 5.2