ML20198F065
| ML20198F065 | |
| Person / Time | |
|---|---|
| Issue date: | 11/05/1985 |
| From: | Merschoff E, Naidu K NRC |
| To: | |
| Shared Package | |
| ML20198F063 | List: |
| References | |
| REF-QA-99900773 NUDOCS 8511140245 | |
| Download: ML20198F065 (6) | |
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ORGANIZATION: SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION INSPECTION NO.t 99900773/85-01 DATE(S1:
5/13-14/85 ON-SITE HOURS:
10 CORRESPONDENCE ADDRESS: Siemens Allis Inc.
- Switchgear Division ATTN: Mr. H. A. Hincks, P.O. Box 29503 General Manager Raleigh, North Carolina U626 ORGANIZATIONAL CONTACT: Mr. Richard Giuli TELEPHONE NUMBER:
(919) 365-6660 PRINCIPAL PRODUCT: 6.9KV/4.16KV Electrical Switchgear and 480 volt metal clad switchgear.
NUCLEAR INDUSTRY ACTIVITY: Switchgear supplied to nuclear power plants account for less than 1% of Siemens-Allis' business. The manufacture of switchgear was previously under the name of West Allis in Wisconsin.
n
/0/24II ASSIGNED INSPECTOR:
( w K. R. Naidu, Reactive Inspection Section, (RIS)
Date OTHERINSPECTOR(S): None APPROVED BY:
//!r!rr E.W.Merschoff,g/ctionChief,RIS Date INSPECTION BASES AND SCOPE:
A.
BASES:
10 CFR 50 Appendix B and 10 CFR Part 21 B.
SCOPE: Review the implementation of the QA Program at the Wendell and Sanford plants; corrective action taken on 10 CFR Part 21 defects and other nonconformances identified on the 6.9 KV switchgear installed at Shearon Harris.
PLANT SITE APPLICABILITY:
Shearon Harris Nuclear Power Plant 400 8511140245 B51113 PDR GA999 EMvsIEMA 99900773 PDR
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ORGANIZATION: SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION NO. 99900773/85-01 RESULTS:
PAGE 2 of 6 A.
Inspection Issues Carolina Power & Light Company (CPL) identified the following defects in the 6.9 KV switchgear installed at the Shearon Harris nuclear power plant. These defects were observed during routine maintenance after cycling the breakers.
1.
50.55(e) & Part 21: On August 13, 1984, CPL reported to the NRC that the welds attaching various structural members in the 6.9 KV switchgear metal housing did not meet the applicable drawing requirements.
2.
50.55(e) & Part 21: On September 7, 1984, CPL reported to the NRC that the lugs on the secondary disconnect of some circuit breakers were bent 90 or more during installation.
3.
50.55(e) & Part 21: On November 30, 1984, CPL reported to the NRC that in some circuit breakers the electrical leads to the anti-pump relay were in contact with the rotating shaft of the spring charging motor. This could ultimately result in a short circuit, causing the anti-pump relay to fail.
4.
50.55(e) & Part 21: On March 1, 1985, CPL reported to the NRC that the sizes of certain circuit breaker secondary disconnect fingers were not uniform. The variation in lengths affects the quality of the connections at the secondary disconnect.
5.
On March 26, 1984, CPL identified in a Nonconformance Report (NCR) that during routine cycling of one circuit breaker, the trip coil would remain energized preventing the circuit breaker from being closed. The only way to restore operability was to disconnect the control voltage source and then re-energize the circuit breaker.
6.
During 1985, electrical maintenance personnel observed partially broken arcing tips in some circuit breakers, during routine maintenance. The observations were documented in an NCR.
7.
During 1985, electrical maintenance personnel observed during routine maintenance that the barriers above and behind the stationary circuit breaker contacts were broken in some circuit breakers. These barriers help to move the arc, generated during a power interruption, in the upward direction. The observations were documented in an NCR.
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ORGANIZATION:
SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION NO. 99900773/85-01 RESULTS:
PAGE 3 of 6 9.
Background Information The switchgear supplied to Shearon Harris was designed and manufactured in Wisconsin by West Allis.
Subsequently, Siemens-Allis, a. joint venture between Siemens A. G. of West Germany and Allis Chalmers, took over the West Allis facility. The operation was then moved to Sanford and Wendell, North Carolina. The switchgear is currently assembled at the Wendell facility with components fabricated at the Sanford plant.
The operations manager at Sanford reports to the general manager located at the Wendell facility. There are two Managers of Quality Assurance who implement the program independently at their respective facilities.
C.
Corrective Action Taken on the Identified Deficiencies The inspector discussed the corrective action taken by Siemens-Allis to address the various deficiencies noted in Section A of this report and reviewed the implementation of corrective actions taken on 50.55 (e) & Part 21 defects during an inspection at the Shearon Harris nuclear power plant on July 9, 1985. These deficiencies relate solely to the Shearon Harris plant because Seimens-Allis did not furnish 6.9 KV switchgear to any other nuclear power plant.
1.
Improper welds The welds attaching the structural steel members in the 6.9 KV switchgear housing uere inspected using Siemens-Allis drawings 18-454-678-501 and 18-287-970-502 titled " Front Frame Assembly" and
" Floor Plate Assembly," respectively.
Unacceptable welds were repaired, reinspected and determined acceptable.
2.
Bent secondary disconnect terminals A procedur'e was developed and implemented to correct the terminal lugs on the secondary disconnects.
Seimens-Allis concurred with the procedure and had a service representative present when the work was being performed.
3.
Inadequate clearance beteen anti-pump relay and the rotating shaft of the spring charging motor The circuit breakers were inspected..1 the wires were separated in such a way that they do not rest on the shaft.
ORGANIZATION: SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION NO. 99900773/85-01 RESULTS:
PAGE 4 of 6 4.
Non-uniform secondary disconnect fingers The non-uniformity in the length of the secondary disconnect fingers is due to variations in the manufacturing process and affects the quality of the connections at the secondary disconnect. Siemens-Allis revised the manufacturing process for these fingers and selected a vendor to manufacture new finger contacts.
New finger contacts were supplied to replace the existing ones.
D.
Inspection cf 6.9 KV Switchgear The inspector accompanied by the NRC resident inspectors and representatives of Siemens-Allis and CPL inspected the 6.9 KV switchgear installation at the Shearon-Harris nuclear power plant on July 8, 1985. The purpose was to observe the defeciencies documented in Nonconformance Reports (NCRs) by CPL maintnenace personnel.
The identified deficiencies were observed during routine maintenance. The plant electrical maintenance personnel disassembled those circiut breakers which. 'tained specific deficiencies identified below in items 2, 3, and 4.
1.
Circuit breaker trip coil remains energized and prevents the breaker from closing Investigation by Siemens-Allis determined that this problem occurred due to the control wiring of the trip coil.
It was CPL and Ebasco's intent to monitor the trip coil both in the breaker closed and breaker open positions. This was not a Siemens-Allis standard wiring technique and therefore Siemens-Allis was unaware that there is sufficient current through the green indicator light to hold the trip coil in an energized state once the breaker is tripped. The circuitry was changed by connecting the green indicating light to the negative terminal instead of the the positive terminal of the trip coil.
Siemens-Allis. supplied a long wire to replace the one which connected the green indicator light to the positive side of the trip coil. Corrective action was completed, tested, and determined acceptable.
2.
A problem unique to only one circuit breaker was demonstrated.
In this breaker, when the foot pedal was operated, occassionally, the foot pedal would slide out of the assembly and render it inoperable for a subsequent closure, and it is not possible to observe that the breaker is in this condition. The primary function of the foot pedal is to trip the breaker when the breaker is in the
o ORGANIZATION: SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION NO.*99900773/85-01 RESULTS:
PAGE 5 of 6 test or connect oosition, by actuating an interlock mechanism. The foot pedal assembly consists of a cylindrical rod in a spring resting on a horizontally mounted cylindrical anchor bolt. Siemens-Allis representatives discussed this observation with their engineering personnel after the inspection and informed the inspector on August 22, 1985, that they recommended the use of 100% silicon rubber and silicon adhesive sealant type RTV 732-clear to hold the foot pedal assembly together without slipping. Siemens-Allis informed Shearon Harris plant personnel that they would supply the material including a procedure to accomplish this modification.
3.
The plant maintenance personnel disassembled the arc chute mechanism of a circuit breaker known to have paritally broken arcing tips. Arcing tips are special alloy inserts mounted on the stationary contacts which mate with the moving contacts surface. After the inspection, Siemens-Allis representatives, after consultation with their engineering personnel, informed the inspector on August 22, 1985, that they expect some breakage to occur due to the nature of the material in the arcing inserts and recomended replacement of the arcing contacts if they are observed to be damaged, badly pitted, burned or broken, during regular periodic maintenance.
4.
Broken barriers The barriers are located behind and above the stationary contacts and help to move the are generated during a power interruption in an upward direction. The barrier material is of a ceramic composition and is expected to receive some damage during normal operation.
Siemens-Allis recommends inspection of the barriers during periodic maintenance and replacement if found damaged.
E.
Plant Tour at Wendell, N.C.
The inspector toured the facility and observed the assembly of 13.8KV switchgear. Work related to switchgear intended for nuclear power plants was not in progress.
F.
Plant Tour at Sanford, N.C.
The inspector toured the facility and observed the various stations where 480 volt circuit-breakers and 4.16KV breakers are assembled and tested.
In-process QC inspections were observed being performed on components and documented on travellers.
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O ORGANIZATION: SIEMENS - ALLIS INC.
RALEIGH, NORTH CAROLINA REPORT INSPECTION NO..QQQOO773/85-01 RESULTS:
PAGE 6 of 6-G.
Conclusion Appropriate corrective action has been taken or initiated on each of the identified problems.
H.
Exit Meeting The inspector met with the persons identified in Section I, and discussed the scope, findings and results of inspection.
I.
Persons Contacted Siemens - Allis, Wendell R. D. Giuli, Manager, Quality Assurance B. J. Stracqulursi, Senior Quality Engineer Siemens - Allis, Sanford K. A. Seitz, Manager, Quality Assurance l
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