ML20198F494
| ML20198F494 | |
| Person / Time | |
|---|---|
| Issue date: | 10/31/1985 |
| From: | Merschoff E, Naidu K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| Shared Package | |
| ML20198F487 | List: |
| References | |
| REF-QA-99900835 NUDOCS 8511140369 | |
| Download: ML20198F494 (7) | |
Text
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dRGANIZATION: BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION INSPECTION NO.: 99900835/85-01 DATES:
7/24-26/85 ON-SITE HOURS: 20 CORRESPONDENCE ADDRESS:
BBC Brown Boveri, Inc.
ATTN: Mr. F. M. D' Antonio General Manager 167 Overland Drive West Columbia, South Carolina 29171-4659 ORGANIZATIONAL CONTACT:
L. H. Schmidt, Manager, Quality Assurance TELEPHONE NUMBER:
803-796-9502 PRINCIPAL PRODUCT: Medium voltage and low voltage circuit breakers.
NUCLEAR INDUSTRY ACTIVITY: Less than 10%.
ASSIGNED INSPECTOR:
/J
/0/M !C K. R. Naidu, Reacti've Inspection Section (RIS)
Date' OTHER INSPECTOR (S):
/o!si er APPROVED BY:
E. W. Perschoff,/J41ef, RIS, Vendor Program Branch Date
{
INSPECTION BASES AND SCOPE:
A.
BASES:
10 CFR Part 21 and 10 CFR 50 Appendix B.
B.
SCOPE:
Implementation of 10 CFR 50 Appendix B, corrective action taken on deficiencies identified at the Shearon Harris nuclear power plant and action taken on previously reported 10 CFR Part 21 defects.
PLANT SITE APPLICABILITY: Shearon Harris, 50-400; Zimmer, 50-358; Bellefonte 50-438; Perry 1 & 2 50-440/441; Enrico Fermi, 50-341; Rancho Seco 50-312.
l l
l 8511140369 851113 PDR QA999 ENVBBC 99900835 PDR
o ORGANIZATION:
BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION N0.: 99900835/85-01 RESULTS:
PAGE 2 of 7 A.
Inspection Issues 1.
Shearon Harris nuclear power plant personnel identified problems during receipt inspections of refurbished 480 Volt circuit breakers supplied by BBC Brown Boveri (BBC). The refurbished circuit breakers incorporated design improvements made as a result of tests to meet Underwriter Laboratories (UL) requirements.
2.
BBC reported to the NRC in March,1983, a potential 10 CFR Part 21 defect related to a broken limit switch carrier. This condition was observed in the 5 KV circuit breakers installed in the Zimmer nuclear power station. Tennessee Valley Authority discovered similar problems in the circuit breakers installed at the Bellefonte nuclear power plant.
3.
BBC reported to the NRC in October,1983, a potential 10 CFR Part 21 defect related to cracked or broken buffer piston rods in 5 HK 250/300 type circuit breakers. This condition was identified in the 5 KV circuit breakers installed at the Fermi nuclear power plant.
4.
BBC reported to the NRC in March, 1985, a potential to damage the auxiliary switch internal wiring when the 480 volt circuit breaker was in a certain position in the switchgear. This condition was observed in the circuit breakers installed at the Seabrook nuclear power station.
5.
BBC reported to the NRC in May,1985, a potential 10 CFR Part 21 defect related to the assembly of 480 volt circuit breakers with incorrect short time delay band levers (links).
The use of the incorrect link could cause the short time element to be inoperative in the maximum band.
The objective of this inspection was to verify the implementation of the BBC quality assurance program at the Columbia facility relative to the corrective action taken to rectify the problems identified at Shearon Harris and to review action taken on previously reported 10 CFR Part 21 defects.
B.
Background Information BBC manufactures medium voltage and low voltage circuit breakers originally designed by the ITE-Imperial Corporation.
BBC developed
c ORGANIZATION: BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION N0.: 99900835/85-01 RESULTS:
PAGE 3 of 7 an LK-line of circuit breakers which required additional testing to meet UL approval. Based on the results of these tests, BBC made some modifica-tions and is supplying refurbished circuit breakers to Shearon Harris to replace the ones already supplied. The replacement consists of removing the existing circuit breaker from its enclosure and racking in the refurbished circuit breaker. All the breakers are assembled in the BBC Columbia, South Carolina facility, which serves as the headquarters for two other facilities located at Florence and Woodruff, South Carolina.
The sheet metal enclosures for the circuit breakers are fabricated at Florence. The plastic molding components such as bushing insulators, solenoid coils, and ceramic instrument transformers are manufactured at the Woodruff facility.
C.
Action Taken on Part 21 Reports 1.
Incorrect Overcurrent Trip Devices BBC informed the NRC in letters dated May 13 and June 6,1985 that incorrect short time delay (STD) band levers (links) had been installed in the electro-mechanical overcurrent trip devices in 480 volt circuit breakers. The use of this link could limit the travel of the short time delay armature and cause the short time element to be inoperative in the maximum band. The overcurrent trip device has three ranges: Minimum (MIN), Intermediate (INT) and Maximum (MAX).
BBC took the following corrective actions:
a.
Notified all the nuclear power plants utilizing K-line circuit breakers with OD-4 or OD-5 electro-mechanical overcurrent trip devices to inspect their breakers to determine whether they have the corqct links.
BBC sent a drawing showing the link, b.
BBC inspected the bin containing the links and removed the incorrect links.
c.
The factory test procedure was revised.
Prior to the revision, the circuit breaker was tested with the short time delay (STD) selected in the MIN position only. The circuit breaker trips correctly at this setting. After the revision, the circuit breakers are tested with the STD in all the three positions - MIN, INT, and MAX.
ORGANIZATION: BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION N0.: 99900835/85-01 RESULTS:
PAGE 4 of 7 2.
Potential for Damaging Auxiliary Switch Wiring BBC informed the NRC in a letter dated March 19, 1985, that based on information provided by Seabrook Nuclear Power Plant, there was a potential for damaging the auxiliary switch wiring when the circuit breaker is racked out to the full disconnect position with the compartment door closed.
In this position, there is a potential for the control wire insulation on the auxiliary switch to be cut by the top edge of the dust shield.
BBC provided instructions to all nuclear power plants in procedure 18-8503 to repair and protect the control wire insulation. The procedure recommended two corrective actions for circuit breakers which sustained damage, a.
To repair any damaged control wiring by sliding a heat shrink tubing over the damaged wires.
b.
Attach adhesive backed foam gasket material to the dust cover where it comes into contact with the control wiring.
c.
If the control wiring was not damaged, the adhesive backed foam gasket then only needed to be attached to the gasket cover.
3.
Cracked Puffer Piston Rods in SKV Circuit Breakers BBC informed the NRC in a letter dated October 5, 1983 that Detroit Edison Company discovered some cracked or broken puffer piston rods in the SHK 250/350 type circuit breakers.
The puffer piston rod is an integral part of the puffer piston assembly. The puffer piston assembly in the SHK circuit breaker performs two functions.
For low current interruptions, the puffer piston is needed to assist the magnetic forces to move the arc into the interrupting chamber. The puffer piston also provides a pneumatic cushion which reduces the shock forces imposed on the mechanism and current carrying parts on opening.
For lower values of current, arc interruption could be adversely affected by failure of the puffer piston to extinguish the arc. Mechanically, loss of a puffer piston rod assembly could reduce the number of operations before maintenance would be necessary.
BBC recommended that all users inspect the SKV circuit breakers for this condition at normal maintenance intervals and to replace cracked or broken puffer piston rods.
ORGANIZATION: BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION NO.: 99900835/85-01 RESULTS:
PAGE 5 of 7 BBC revised drawing 19364 for the puffer piston rod. Revision 12 dated March 1, 1985 requires this part to be machined at the end to which it is bolted to the puffer piston to a tolerance of 90 + 1/4*.
Also, this part is made from glass reinforced Nylon material.-
4.
Broken Limit Switch Carriers in Medium Voltage Breakers BBC notified the NRC in a letter dated March 22, 1983 that a broken limit switch carrier was observed in the HK control device in the circuit breakers installed at the Zimmer nuclear power plant. This particular control device is used on circuit breakers types 7.5 kV, 500 through 750 MVA; 5 HK 350, 3000; and HKV circuit breakers.
Tennessee Valley Authority identified similar problems on July 3, 1985 in the ciccuit breakers installed at the Bellefonte nuclear power plant.
BBC developed procedure 1B-8303 Revision 1 dated June 11, 1985,
" Instructions for inspecting, adjusting and/or replacement of parts for obtaining limit switch adjustments on BBC 7.5 KV through 15 KV, 500 thru 750 MVA; SHK 350, 3000; all HKV breakers".
BBC recommended that this procedure be factored into the Bellefonte circuit breaker checkout procedures and agreed to furnish level stops if necessary.
BBC stated that corrective action on the problems at the Zimmer nuclear power plant were complete.
D.
Inspection Findings and Other Comments 1.
Shop Tour The QA Manager accompanied the inspector on a shop tour which included the areas of receipt inspection, storage of material, automatic crimping machine, assembly of medium and low voltage circuit breakers and circuit breaker testing.
Established work procedures were available at the work stations.
2.
Review of Corrective Action Taken on Problems Identified at Shearon Harris a.
Plant personnel at Shearon Harris identified broken strands of wire at the connectors in 3 of the 5 refurbished circuit breakers during receipt inspections. The Quality Control manager organized a training session on January 15, 1985 to indoctrinate
o ORGANIZATION: BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION NO.: 99900835/85-01 RESULTS:
PAGE 6 of 7 the craftsmen and QC inspectors. A representative of " AMP", the manufacturer of the automatic crimping machine, lugs and the hand crimping tool, conducted three training sessions to accommodate all craftsmen. Each training session lasted 45 minutes and included a short film, discussion and " hands on" demonstration.
BBC QC inspectors perform weekly audits to determine the adequacy of the crimping.
b.
Plant personnel at Shearon Harris identified that some refurbished circuit breakers were not smoothly travelling into the stationary cabinet when racked in. BBC determined that the primary contact stubs in the stationary switchgear cubicle were not penetrating the refurbished breaker contacts.
BBC supplied primary contact stub replacements and a field representative is coordinating the installation, c.
Plant personnel at Shearon Harris developed a procedure 1/2-9000-E-09 for inspection, and maintenance of the BBC circuit breakers. This procedure reflects BBC installation and maintenance instructions IB.6.1.1.7-Ic.
Plant personnel were experiencing problems implementing this procedure relative to the Magnetic Latch Verification.
BBC stated that this was a manufacturer's verification requirement to be performed only at the factory and requested that the plant personnel delete this verification from the procedure.
The plant personnel agreed to revise the procedure to incorporate this and other recommendations.
Observation of Circuit Breaker Testing s.
The inspector observed the testing of a circuit breaker which was sent to BBC from the Rancho Seco nuclear power plant. The control room operator was unable to close this circuit breaker from the main control board. The standard BBC test procedure was followed and the results documented. The circuit breaker tested satisfactorily.
BBC personnel evaluated the field service report and theorized that the stationary disconnect contacts (SDC) in the cell may have a film of oxidation which prevented proper contact engagement of the circuit breaker contacts resulting in high resistance and inadequate control power to close the breaker.
BBC recommended that Rancho Seco replace the SDC in this cell and inspect the SDCs in all other cells.
a ORGANIZATION:
BBC BROWN B0 VERI, INC.
WEST COLUMBIA, SOUTH CAROLINA REPORT INSPECTION N0.: 99900835/85-01 RESULTS:
PAGE 7 of 7 4.
Conclusion Appropriate corrective action has been taken or initiated on each of the identified problems.
E.
Persons Contacted 1.
BBC Brown Boveri, Inc.
- F. M. D' Antonio, General Manager E. W. Rhoads, Corporate QA Manager
- L. P. Schmidt, QA Manager, Columbia M. D. Sigmon, Product / Test Engineer W. R. Wilhelm, QC Manager A. Danielson, Assembly Supervisor, LK Line Circuit Breakers 2.
Sacramento Municipal Utility District - Ranche Seco Power Plant J. Griffith, QC Electrical Inspector J. Wheeler, Maintenance Engineer
- Denotes those individuals present at the exit interview on July 26, 1985.
F.
Exit Interview The inspector met with individuals identified in~Section E of this report at the conclusion of the inspection and discussed the scope and findings.