ML17309A838
| ML17309A838 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 06/24/1996 |
| From: | Wessman R NRC (Affiliation Not Assigned) |
| To: | Hebdon F NRC (Affiliation Not Assigned) |
| Shared Package | |
| ML17309A839 | List: |
| References | |
| TAC-M95274, TAC-M95275, NUDOCS 9606280043 | |
| Download: ML17309A838 (5) | |
Text
0 Oune 24, 1996 MEMORANDUM To:
Frederick J.
Hebdon, Director Project Directorate II-3 Division of Reactor Projects I/II FROH:
SUBJECT:
Richard H. chessman, Chief Hechanical Engineering Branch Division of Engineering TECHNICAL ASSISTANCE REQUEST (TIA 96-007)
REGULATORY ACCEPTABILITY OF PRELUBRICATING VALVES (TAC Nos. H9527I/H95275)
In a seeorandua dated April 12, 1996, Ellis M. Herschoff, Director, Division of Reactor Projects, Region II, discussed the determination by Region II inspectors that the licensee of the St. Lucie nuclear power plant had lubricated a containment spray flow control valve prior to performing stroke time testing under Section XI of the ASHE Boiler 8 Pressure Vessel Code.
The Region II inspectors considered this pre-lubrication to result in a nonrepresentative test of valve capabilities.
Region II requested the Office of Nuclear Reactor Regulation (NRR) staff to respond to specific questions on the acceptability of the licensee's actions in pre-lubricating valves prior to testing.
Attached is our response to those questions.
CONTACT:
T. Scarbrough, DE/EHEB 415-279'ocket Nos.:
50-335 50-389
Attachment:
As stated cc w/attachaent:
J. T. jiggins A. F. Gibson G. E. Grant T. P.
Gwynn Central Files EHEB RF/CHRON LWiens RCroteau Valve List DOCUMENT NAME: G:(SCARBROU~RNLUBE and PRECOND To receive
~ c of th(a docent (ndfcate fn the box CK M/o attachaant/encloaure EK stth attachment/enclosure M e No OFFICE NAME DATE T car ro
~Y/96 EHEB:DE Riess 96 COPY ATTACHMENT
REGULATORY ACCEPTABILITY OF PRE'BRICATING VALVES PRIOR TO SURVEILLANCE TESTING (TIA 96-007)
In a aeaerandua dated April 12, 1996, Ellis Q. Herschoff, 01rector, Divis1on of Reactor Projects, Region II, discussed the deterwination by Region II inspectors that the licensee of the St. Lucie nuclear power plant had lubricated a containwent spray flow control valve prior to perforwing stroke-time testing under Section XI of the ASHE Boiler and Pressure Vessel (BLPV)
Code.
The Region II inspectors considered this pre-lubrication to result in a nonrepresentative test of valve capabilities.
Therefore, Region II requested a response to the following questions:
l.
Is the practice of lubricating a valve prior to stroke-time test1ng acceptable under the regulations?
2.
Is the purpose of stroke-tiwe testing under ASHE Section XI to demonstrate the current and past operability of a valve, the current and future operability of a valve, or both?
QiL~aaihm The NRC regulations in 10 CFR 50.55a requ1re that nuclear power plant licensees provide valves and pwaps within the scope of Section XI of the ASHE BtPV Code with access to enable the performance of inservice test1ng of those valves and pumps for assessing operational readiness as set forth in Section XI of the ASHE fRPV Code.
Criterion XI, "Test Control," of Appendix B
to 10 CFR.50 requires that testing be performed under suitable environmental conditions.
The 'current Inservice Testing (IST) Programs at St. Lucie Units I and 2 are based on the requirements of Section XI of the ASHE B8PV Code, 1986
,Edition, with approved relief to certain requirements.
Article IN-1000 of ASHE B5PV Code (1986 Edition),Section XI, states that it pt ov1des the rules and requireaents for inservice testing to assess operational readiness of certain Class I, 2, and 3 valves in nuclear power plants, which are required to perform a specific function in shutting down a reactor to the cold shutdown condition, in mitigating the consequences of an accident, or in providing overpressure protection.
Subarticle IVV-3417 of the 1986 ASHE MPV Code states that, 1f a valve fails to exhibit the required change of valve stew or disk position or exceeds its specified limiting value of full-stroke time by this testing, the licensee shall initiate corrective act1on ieaediately with the valve declared 1noperative if the condition is not corrected in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
Generic Letter (GL) 89-04, "Guidance on Developing Acceptable Inservice Testing Programs,"
in Position 8 indicates that, rather than delaying 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the licensee should sake a decision on operability when the data is recognized as being within the required action range.
GL 91-18, 'Inforwation to Licensees Regarding Two NRC Inspection Hanual Sections on Resolution of Degraded and Nonconforaing ATTACHHENT
Conditions and on Operabf1fty," provides similar guidance on the timeliness of operability dacfsfons based on test results.
IVV-341? also requires that the test frequency be increased if a significantly longer stroke time is observed since the last test.
Finally, IVV-3417 requires that any abnormality or erratic action be reported.
The St, Lucfe IST Program Plan identifies no differences in interpretation of the NRC regulations or ASME Code when stating that the inservice testing in the plan fs to be performed specifically to verify the operational readiness of pumps and valves which have a specific function in mitigating the consequences of an accident or in bringing the reactor to a safe shutdown.
Nore recent ASIDE codes and standards have repeated and amplified the importance of evaluating the operability of valves during inservice testing.
For example, Subsection ISTC, "Inservice Testing of Valves in Light-Water Reactor Power Plants,'f the AWE Operation and Maintenance (Nc) Code states that it establishes requfrements for inservice testing to assess the operational readiness of certain valves and pumps used in nuclear power plants.
Subsection ISTC 4.2.9 requires that the valve be fmnedfately declared inoperable ff the valve exceeds the limiting values of full stroke time.
Subsection ISTC 4.2.4 also requires that any abnormality or erratic action be
'ecorded and that an evaluation be made regarding the need for corrective action.
The NRC regulations, and ASIDE codes and standards, clearly indicate that the purpose of the fnservfce testing programs fs to "assess" the operational readiness of the valves and pumps.
Article IWA-9000, "Glossary," of ASHE 85PV Code (1986 Edition),Section XI, defines "assess" as determining "by evaluation of data compared with previously obtained data such as operating data or design specifications."
Hore generally, webster's II New Riverside University Dictionary defines "assess" as "to appraise or evaluate."
If maintenance is performed prior to fnservfce testing that ensures the capability of a valve or pump to operate properly, the licensee's IST program would be unable to evaluate the operational readiness of the component.
This fs reinforced by the requirement fn the ASIDE Code that, ff the stroke-time limits are exceeded, the condition be corrected or the valve be considered inoperable.
The St. Lucie IST Program Plan intent "to verify the operational readiness" fs more specific regarding the purpose of the. testing to determfne the capability of the valves to perfora their safety function.
The ASME Code recognizes that routine preventive maintenance will be performed by licensees.
In some instances, this maintenance may occur shortly before a
scheduled test required by a licensee's IST program.
The effect of this maintenance on the validity of the test to assess operational readiness should be evaluated.
In Sectioa 3.5, 'Testing in the As-Found Condition," of NUREG-1482 (April 1995), 'Guidelines for Inservice Testing at Nuclear Power Plants,'he staff stated that the Code does not specifically require testing to be performed for components in the as-found condition except for. safety and relief valves, but does not define as-found even fn the context of safety and relief valves.
In NUREG-1482, the staff noted fts belief that Nost fnservice testing fs performed fn a manner that generally represents the condition of a standby component ff ft were actuated fn the event of an accident (f.e.,
no pre-conditioning prior to actuation).
In NRC Inforwation Notice 96-24 (April 25, 1996), "Preconditioning of Holded-Case Circuit Breakers Before Surveillance Testing,'he staff stated that the practice of preconditioning molded-case circuit breakers (for example, by lubricating pivot points and manually cycling the breaker) defeats the purpose of the periodic test.
The staff stated that such preconditioning does not conf)ra continued oper ability between tests nor does it provide information on the condition of the circuit breaker for trending purposes.
The applicable licensee planned to revise its procedures before the next surveillance test t correct this situation.
e ance es o
In ASHE Code Case ON-1, "Alternative Rules for Preservice and Inservice Testing of Certain Electric Hotor Operated Valve Assemblies in LWR Power Plants (OH - Code 1995 Edition; Subsection ISTC)," the ASHE provides an alternative to the stroke-time testing requirements of the OH Code to assess the operational readiness of wotor-operated valves (HOVs).
The code case uses the saic language as the NRC regulations and ASHE Code in stating that inservice testing is intended to assess the operational readiness of valves.
In iapleaenting the code case, the licensee is required to deterwine the capability of the HOY during inservice testing.
The code case requires HOVs to be cycled at least every refueling cycle with diagnostic testing conducted on periodic intervals.
The code case allows grouping of HOVs with the inforwation obtained froa individual HOV tests applied to other HOYs in the group.
In Section 3.3, the code case specifically states that maintenance activities, such as stee lubrication, shall not be conducted if they might invalidate the as-found condition for inservice testing.
The performance of waintenance prior to testing would defeat the ability to determine any degradation in the operation of the tested HOV and to apply the test results to other HOVs within the group.
This code case is being endorsed (with certain liwitations unrelated to preconditioning) for voluntary use by licensees in a forthcoming generic letter.
In sugary, the perforwance of maintenance on a component to ensure its proper operation prior to conducting a test negates the validity of the test in assessing the operational readiness of the component.
If the waintenance had not been pertormed, the component say not have been capable of performing its safety function.
Clearly, the conduct of maintenance prevents the licensee frow assessing if the component would perforw as design, should it be called upon.
- Further, important information on trending of operating par aweters for evaluating degradation would not be available.
In response to the specific questions from Region II:
1.
The performance of waintenance that ensures the capability of a valve to satisfy the stroke-time test requireaents of the ASHE Code provides a
false indication of the operational readiness of the valve.
Therefore, a licensee activity to lubricate a valve prior to stroke-tiwe testing for the principal purpose of satisfying the test criteria at that specific time would not be considered to be within the intent of the NRC regulations under 10 CFR 50.55a or Appendix B to 10 CFR 50. It is recognized that routine preventive aaintenance, such as valve
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lubrication, sight coincide occasionally with IST prograw testing.
In those cases, the effect of such aaintenance needs to be evaluated to ensure that the ability to assess operational readiness of the valves and to trend degradation in the valve performance are not adversely affected.
2.
The HRC regulations, and ASIDE codes and standards, require licensees to establish IST programs to assess the operational readiness of certain valves and pumps.
If a valve fails its stroke-time test, the licensee is required to declare the valve inoperable.
Therefore, the stroke-time test is intended to demonstrate current operability.
The licensee evaluates past operability since the previous stroke-time test based in part on the most cur rent te'st results.
The ASME Code prescribes comparison of stroke-time test data to previous test data so that licensees may obtain an indication that the valve should remain operable until the next test.
It is recognized that the stroke-tiwe test is limited in its effectiveness