IR 05000338/1986015

Insp Repts 50-338/86-15 & 50-339/86-15 on 860305 & 0505-09. No Violation or Deviation Noted.Major Areas Inspected: Followup on Unit 2 Setpoint Drift of Main Steam Code Valves & Close Out of Open Items

ML20206J510
Person / Time
Site:	North Anna
Issue date:	06/12/1986
From:	Jape F, Schnebli G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20206J506	List: IR 05000338/1986015 ML20206J502
References
50-338-86-15, 50-339-86-15, NUDOCS 8606270185
Download: ML20206J510 (8)

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m3 KEc UNITED STATES oq*o, NUCLEAR REGULATORY COMMISSION

[" ^$ REGION ll y ,j 101 MARIETTA STREET. * ATLANTA, GEORGI A 30323 g

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Report No:;. : 50-338/86-15 and 50-339/86-15 Licensee: Virginia Electric and Power Company Richmond, VA 23261 Docket Nos.: 50-338 and 50-339 License Nos.: NPF-4 and NPF-7 Facility Name: North Anna 1 and 2 Inspection Conducted: March 5, 1986 at Wyle Laboratory, Huntsville, AL-May 5 - 9, 1986 at North Anna Site Inspector: M8/ I d G. A. Schnebli Date Signed Approved by: //gr U F. Jape, Sdttion Chief b [/L!([

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Engineering Branch y j/

Division of Reactor Safety SUMMARY Scope: This was a routine, unannounced inspection in the areas of followup on the setpoint drift of the Unit 2 Main Steam Code Safety Valves and closeout of open item Results: No violations or deviations were identifie PDR ADOCK 05000338 G PDR

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REPORT DETAILS Persons Contacted Licensee Employees

• E. W. Harrell, Station Msnager G. E. Kane, Assistant Station Manager

• Kansle'r, Superintendent of Maintenance

• J. Leberstien, Licensing Coordinator G. Rossetti, Senior Designer D. Thomas, Supervisor Mechanical Maintenance Other licensee employees contacted included engineers, technicians, operators, mechanics, security force members, and office personne NRC Resident Inspector L. King, Resident Inspector

• Attended exit interview Exit Interview The inspection scope and findings were summarized on May 9, 1986, with those persons indicated in paragraph 1 above. The inspector described the areas inspected and discussed in detail the inspection findings. No dissenting comments were received from the license The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspector during this inspectio . Licensee Action on Previous Enforcement Matters (Closed) Violation 338/84-37-03, concernu g the inadequate review of periodic test procedure (See paragraph 6.b) Unresolved Items Unresolved items were not identified during the inspectio . Followup on Main Steam Code Safety Relief Valve (MSRV) Setpoint Drift Problems (92700)

Region II became involved in this issue on February 24, 1986, when informed by the licensee that 8 of 15 Unit 2 MSRVs failed to lift during testing. The Unit was in Mode 3 (llot Standby) and the licensee was performing the periodic testing of the MSRVs in accordance with Section XI of the ASME Boiler and Pressure Vessel Code. The test was conducted in accordance with ASME Performance Test Code (PTC) 25.3 which allows the use of a pneumatic assist test device in addition to the pressure in the main steam header to

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determine the setpoint of the MSRVs. The pneumatic assist test device was used per the instructions provided by the valve vendor, Crosby Valve and l Gage Company, as implemented by the licensee's periodic test procedure 2-PT-70, Main Steam Code Safety Valve Setpoint Verification. Out of the initial sample of five valves (see Attachment I for a summary of test results), two valves would not lif t at the maximum pressure available, two I were found with setpoints to be too high and were subsequently adjusted within specifications, and one was found to be within its setpoint rang Due to the number of failures, additional testing was required by Section XI of the ASME code. In the second sample of five valves, two would not lift, two were found set high and were adjusted, and one was within its rang Testing of the last set of five valves determined that four would not lift and one was high and adjusted to the proper setpoin Due to the excessive number of inoperable valves, the licensee elected to retest the valves utilizing a steam pressure syste W'

y le Labs of Huntsville, Alabama, was contracted to perform the testing and refurbishment of the valves. A total of ten valves were sent to Wyle, on February 28, 1986, eight valves that did not lift; one valve that was found to be within its setpoint; and one valve that was adjusted after its setpoint was determined to be too hig Region II personnel visited Wyle Labs on March 5,1986, to observe testing of the valves. During this trip the inspector was able to witness the testing of one of the valves and noted that the test was conducted in a controlled and professional manner. Test data, which included temperature, pressure, and valve stem motion were recorded on strip charts and carefully analyzed. The testing was repeated on each valve until three successive tests were obtained. Due to the length of time the testing would require, the inspector informed the licensee representative present at W' y le for test witnessing that a followup inspection into this issue would be conducted at the North Anna site when testing was complete The on site followup inspection was conducted May 5 - 9, 1986. In this inspection, data for all testing of Unit 2 MSRVs were reviewed back through the previous outage in September 1984. This included the data generated at Wy le Labs in March 1986, at the site by the licensee in February 1986, and at ITT Henze Labs during the previous outage in September 1984. (See Attachment I for a summary of test results.) Data From Wyle Lab In March 1986 As previously stated, ten valves were sent to Wyle for testing and refurbishment, as required. Nine of ten valves required adjustment because they were out of their setpoint ranges on the high side and one valve was found to be acceptable. Due to the fact one of the valves that required adjustment was previously reset by the licensee at the site, VEPC0 decided to ship the remaining five valves to Wyle for retesting. Testing indicated that three of these were also set on the L _

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high side. During disassembly for repairs, it was noted that the nozzle and guide ring setpoints for 12 of the 15 valves were not per the vendor recommendation Crosby recommends that the guide ring be set at +150 notches and the nozzle ring at -20 notches. The as-found guide ring setpoints varied from +175 to +48 notches and nozzle ring setpoints varied between -21 and - The ring setpoints do not affect valve set pressure, however, they do affect the internal flow characteristics of the valve, in particular percent blowdown. Blowdown is defined as the pressure below setpoint that the valve will resea Percent blowdown for these particular valves (Crosby HA-65) is approximately 4% of setpoint pressure. All 15 MSRVs were subsequently reset to their praper ranges, refurbished, leak tested, and returned to the licensee for reinstallatio b. Data From VEPC0 Site Tests in February 1986 Of the 15 valves tested, eight valves would not lift at all, two valves were satisfactory, and the set point of the remaining five valves were too high and subsequently reset to the proper range. VEPC0 personnel stated that when testing the MSRVs in previous outages, utilizing the pneumatic assist test device, they never encountered the problems observed during this test cycle. A review of their records back through 1982 substantiated this statemen In addition, the licensee informed the inspector that the ring settings had not been reset since the previous outage when the valves were tested and refurbished by another contractor (ITT Henze). This testing is discussed in more detail belo c. Data From ITT Henze in September 1984 In preparation for periodic testing of the MSRVs in September 1984 Unit 2 tripped and the license was unable to test the valves in their normal manner using the pneumatic assist device. The licensee contracted the services of ITT Henze to perform the testing utilizing the steam pressure method. Testing and repairs were accomplished in September and October of 1984. A review of these data indicated that of the 15 valves only one was within its' setpoint range. The other 14 valves all failed on the low side and were subsequently reset to within their setpoint range. The guide and nozzle ring setponts were all set to the vendor specifications of +150 and -20, respectively. The inspector also reviewed the calibration data sheets for the Heise gage

ed in testing the valves. The data indicated the gage was within the rated accuracy of ik% prior to and after the testin .

d. Conclusions The cause of setpoint drift of the MSRVs has not been determined at .

this time and is still under evaluation by the licensee. A review of data available to date and discussions with responsible licensee and contract personnel (both Wyle and ITT Henze) indicated the problem began after ITT Henze refurbished the valves. This observation is based on the following:

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ITT Henze found 14 of 15 MSRVs set too low during the 1984 outage and reset all valves to their required setpoin Setpoints were increased an average of 24 to 119 psig. Values for 2-MS-SV-202A were not used because the valve spring needed replacemen The licensee and Wyle Labs found all 15 valves set too high during the 1986 outage and reset all valves to their required setpoin Setpoints were decreased an average of 14 to 103 psi The combination of licensee and Wyle results were used in this comparison because the licensee readjusted some of the valves prior to shipment to Wyl *

The guide and nozzle ring setpoints were verified to be per Crosby recommendations (+150 and -20) when the valves were refurbished by ITT Henze. However, when the valves were refurbished by Wyle the as-found ring setpoints were found to be out on 12 of the 15 valve Within the areat examined, no violations or deviations were identifie . Followup on Previously Identified Items (92701) (92702) (Closed) Inspector Followup Item (IFI) 338/84-37-02 and 339/84-37-02, Review Current Practice of Maintaining Split Records. This item was a concern in that for those periodic tests performed routinely or as part of a post refueling test program, a complete test package was available on site if the tests were analyzed on site. For the core performance tests, which are analyzed offsite, station records usually consist of the completed copy of the Periodic Test used to obtain the data and a letter from the offsite office reporting the results of their analysis.

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The methods of analysis and analysis work sheets are not part of station records. (When requested by the inspector, nuclear fuel operations personnel were prompt in sending specific analysis procedures and work sheets for review.) Nevertheless, the delay between identifying a need for a record and having it available for review was much greater than for those maintained onsit This issue was addressed by the licensee in a memorandum from C. T. Snow to Distribution dated January 11, 1986, which stated that all records analyzed offsite by the Nuclear Fuel Operation Group would be maintained at the station. At present, the. records are attached to the applicable procedure. These items are close (Closed) Violation 338/84-37-03, Inadequate Review of Periodic Test Procedures. This item was based on the fact that reviews of two periodic test procedures were inadequate in that the tests were issued and performed with certain steps in error. The licensee corrected this problem, as identified in their letter to the NRC dated December 12, 1984, by instructing responsible personnel in the importance of the

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final review process and revised the administrative procedure for governing the review of new and revised procedures, Station Administrative Procedure 5.4. This item is close . . . . .-

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5 (Closed) IFI 339/79-06-03, Recheck Hangers and Snubbers When Unit Is Returned to Cold Shutdown. This item was based on the fact that during the inspection of snubbers during hot functional testing of Unit No. 2, the inspectors observed changes being made to hanger adjustment and  :

deficiencies on snubbers being written by Stone and Webster QC inspection personnel. The inspectors noted that provisions had not been made to recheck these items when the plant was returned to cold conditions. This recheck was performed by the licensee and documented in a memorandum from J. Eastwood to E. Harrell dated May 9, 1979. This item is close Attachment:

MSRV Test Results Summary

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ATTACHMENT I MSRV TEST RESULTS SUMMARY (SEE NOTES ON FOLLOWING PAGE)

ITT Henze VEPCO WLE LABS September 1984 February 1986 March 1986 Set As As A As As A As As A-

. Valve Pressure psig Found Left psig(2). found left psig(2) found left psig(2)

2-MS-SV-201A 1085 (ill) 1044 1084 -41 1109 1094 +24 1105 1093 (5)

2-MS-SV-201B 1085 (ill) 1036 1081 -49 1133 1077 +48 1068 1091 (5)

2-MS-SV-201C 1085 (ill) 1087 1087 Sat (4) --- ---

1133 1084 +48 2-MS-SV-202A 1095 (ill) N/A(3) 1092 ---

1096 1098 +1 Sat 1123 1100 (5)

2-MS-SV-202B 1095 (ill) 1060 1095 -35 (4) --- ---

1166 1088 +71 2-MS-SV-202C 1095 (ill) 1041 1088 -54 (4) --- ---

1147 1097 +52 2-MS-SV-203A 1110 (ill) 1046 1111 -64 1124 1111 +14 1111 1111 (5)

2-MS-SV-2038 1110 (ill) 1084 1119 -26 1125 1106 +15 1196 1116 (5)

2-MS-SV-203C 1110 (ill) 1073 1112 -37 1131 1112 +21 1105 1105 (5)

2-MS-SV-204A 1120 (ill) 1056 1117 -64 1127 1128 +75at 1155 1118 (5)

2-MS-SV-204B 1120 (ill) 1022 1121 -98 (4) --- ---

1182 1117 +62 2-MS-SV-204C 1120 (ill) 1063 1124 -57 (4) --- ---

-1223 1127 +103 2-MS-SV-205A 1135 (ill) 1111 1140 -24 (4) --- ---

1168 1136 +33 2-MS-SV-2058 1135 (ill) 1020 1142 -115 (4) --- ---

1196 1132 +61 2-MS-SV-205C 1135 (ill) 1016 (6) -119 (4) --- ---

1164 1126 +29

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ATTACHMENT I (Continued)

NOTES (1) All values for "As-Found" and "As-Left" pressures are average values if more than one test was performe (2) A psig is the difference between the "As-Found" pressure and the-required " Set Pressure".

(3) Data for this test was not used as the spring appeared compressed and was replace As-found setpoint prior to repair was 640 psi (4) MSRV would not lift at the pressure availabl (5) This data was not computed because valve was previously reset by VEPC0 prior to shipment to Wyle Lab (6) This data appeared to be in error and is presently under evaluation by VEPC l l

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