ML20198C846
| ML20198C846 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 05/14/1986 |
| From: | Edelman M CLEVELAND ELECTRIC ILLUMINATING CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| IEB-85-003, IEB-85-3, PY-CEI-OIE-0206, PY-CEI-OIE-206, NUDOCS 8605230072 | |
| Download: ML20198C846 (9) | |
Text
-.
omB B THE CLEVELAND ELECTR P O. box S000 - CLEVELAND, OHIO 44101 - TELEPHONE (216) 622-9800 - ILLUMINATING BLOG
- 55 PUBLIC SOUARE Sewing The Best Location in the Nation MURRAY R. EDELMAN iflCE PRESIDENT NUC LE A R May 14, 1986 PY-CEI/01E-0206 L Mr. James G. Keppler Director, Region III Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Glen Ellyn, IL.
60137 Perry Nuclear Power Plant Docket Nos. 50-440 50-441 IE Bulletin 85-03 Motor-Operated Valve Failures
Dear Mr. Keppler:
In accordance with the ' request in IE Bulletin 85-03, " Motor Operated Valve Common Mode Failures During Plant Transients Due to Improper Switch Settings,"
this letter and its attachment is provided to (1) report the results of the review of the design basis (Item A) and (2) describe the program to evaluate / change setpoints and demonstrate by test (Items B through D).
CEI is participating in the BWR Owners Group (BWROG) Committee that is developing a generic BWR position for meeting the requirements of IE Bulletin 85-03.
This effort will review the systems involved, to determine the valves within the systems to be tested, and a generic identification of the differential pressure against which valves must open/close.
Each utility will then make this information plant-specific.
In addition to the BWROG, CEI has taken an active role in recent industry discussions on motor operated valve degradations. CEI attended a meeting at the Oak Ridge National Laboratory in February, and more recently hosted a meeting to discuss this Bulletin. The meeting CEI hosted was well attended by utilities with plants supplied by the four NSSS vendors.
o MAY 191986
e James G. Keppler May 14, 1986 PY-CEI/01E-0206 L l
l The attachment describes our program to addressBulletin 85-03 action Items A through D.
Based on the results of the BWROG effort in response to this Bulletin, which is scheduled to be completed in September, CEI will provide updated information regarding the required operability testing at that time.
Please call if you have any questions.
Very truly yours, y&c)
Murray R. Edelman Vice President Nuclear Group MREinj e Attachment cc: Jay Silberg, Esq.
John Stefano (2)
J. Grobe U.S. Nuclear Regulatory Commission Office Of Inspection and Enforcement Washington, D. C.
20555 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C.
20555
Attachment PY-CEI/01E-0206 L Page I of 7 A.
Design Basis The cm.atrol switch settings for the motor-operated valves (MOV's) in safety-related systems are based on the maximum differential pressures identified for the valves in the Final Safety Analysis Report (FSAR). As part of the valve procurement. process, the vendors were required to prove valve operability at maximum system pressure. The torque switch setpoints that resulted from this testing were verified and used as the basis for
.the design setpoints.
Typically the motor-operated valves used in the Emergency Core Cooling Systems (ECCS) employ the following control switch scheme.
In the opening direction only a position limit switch contact is used to control valve stroke. The useage of only a limit switch contact eliminates the possibility of the valve not opening on demand due to an incorrectly set torque bypass switch. In the closing direction a combination of torque and limit switches connected in a parallel arrangement is used to control valve stroke. This arrangement allows for positive valve closure by using the limit switch to control valve disc movement until the point just prior
- to disc seating. At this point the limit switch drops out of the circuit and the torque switch controls disc seating thereby preventing valve dise damage due to overtorquing the disc into the valve's seat.
This control switch scheme for the ECCS motor-operated valves is the General Electire Company standard design.
The control switch settings take into account inadvertent equipment operations and line breaks. The control switch settings are designed to provide positive valve actuation up to the maximum differential pressures expected to be seen across the valve in either the open or close direction during a design basis accident condition. This envelopes single equipment failure or inadvertent equipment operation.
CEI has reviewed the design basis for the operation of each of the motor-operated ~ valves in the High Pressure Core Spray and the Reactor Core Isolation Cooling Systems, that are required to be tested for operational readiness in accordance with 10CFR50.55a(g) as shown on the attached
_ preliminary summary table.
The maximum differential pressure for the Reactor Core Isolation Cooling System (RCIC) motor-operated valves are obtained from FSAR Table 5.4-2.
The maximum differential pressures for the High Pressure Core Spray System (HPCS) valves are obtained from the FSAR Figure 6.3-1.
The valve listing, taken from our Inservice Inspection Program meets the requirements in 10 CFR 50.55a(g).
Attachmtnt PY-CEI/OIE-0206 L Page 2 of 7 B.
Motor-Oparated Valve Control Switch Setting CEl has reviewed the programs for establishing and setting all switch settings for each valve operation. Our programs have been in place since late 1984 and provide appropriate methods for selecting and setting torque, torque bypass and position limit switches, as described below.
CEl does not use motor thermal overload protection on the motor-operated valves at Perry.
The position limit switch and the torque bypass position limit switch settings are identified on the Electrical Elementary Diagrams (design drawings) for the valven. The torque switch setpoints are listed in the Perry Master Setpoint List which is a controlled design document.
Revisions to the motor-operated valves control switch setting are design changes. Both the maintenance and design control instruction. require an approved design change document prior to changing a control switch setting.
The methodology for establishing and revising a torque switch setpoint is as follows. The initial setpoint is the vendor supplied setpoint for the Design Basis Accident. The only case where the setpoint will be lowered from this value is when the vendors concurrence to the change is obtained or a calculation and testing verifies the lower setpoint. The testing method encompasses either dif ferential pressure testing or motor-operated valve control switch and output thrust signature analysis.
The methodology for establishing position limit switch settings is based on the position needs for the valve. The position limits are set in accordance with the position on the Electrical Elementary Diagram. The j
position settings take into account the inertial movement (coast downtime) of the valve disc after limit switch trip to prevent damage to the valve stem and the disc. The torque bypass position limits are based on the time required to break the valve disc free in relation to total valve stroke time. This is typically 5% to 7% of the valve stroke time. The torque bypass setting also takes into account the effect on the position indication lights in the control room.
l
m Attachment PY-CEI/0IE-0206 L Page 3 of 7 C.
Testing CEI 's program for controlling motor-operated valve control switch settings was in place as part of the preoperatonal test program.- Thus, the initial settings have been properly selected, implemented and maintained.
To demonstrate operability, CEI will test the motor-operated valves in the RCIC and HPCS systems. This scope will be further defined by the review being conducted by the BWROG. The preliminary scope of testing will include the valves as listed on the attached table. It is our intent to perform the majority of the testing during the power ascension test program. All testing will be completed on or before November 15, 1987.
As part of the testing, the actual running characteristics of actuators will be recorded. This will include torque and limit switch actuation points vs. load, motor current and output thrust in both the opening and' closing direction. The signature traces will be used to determine the adequacy of the control switch settings with respect to Design Basis Accident Condition. The testing will be performed at normal system pressures. The justification for the test methodology will be provided in the summary report with the testing results.
The valve test system identified'in NUREG CR4380 will be used to obtain the valve actuators's operating characteristics. The signature traces that will be obtained from the operability testing will be analyzed with a computer sof tware package to help determine the adequacy of the control switch settings. The software program is basically an oscilloscope waveform analysis program that can be used to analyze any signature.
Also, actuator thrust calculations will be performed to the required thrust to provide positive valve actuation in all plant conditions.
In summary, the valve control' switch settings will be verified through a combination of the following methods:
1.
Operability testing at normal system pressure.
2.
Actuator operating characteristics analysis.
3.
Control switch setting design calculations.
4
r-I Attachment PY-CEI/OIE-0206 L Page 4 of 7 D.
Procedures CEI has reviewed plant procedures and determined that the existing procedures meet the programmatic recommendations of this Bulletin in establishing, maintaining and controlling motor-operated valve control switch settings.
Engineering, through the design control program, identifies the torque
' switch settings as design setpoints. To establish or revise a setpoint an approved design output document is required per the Control of Setpoints procedure. The position limit switches require an approved design change package to establish or revise the settings.
Maintenance, through the General Electrical Instruction for Limitorque Limit / Torque Switch Adjustments, requires that the control switches be set in accordance with the appropriate design documents.
In addition, Quality Assurance provides surveillance and inspection of the work activities associated with safety related MOV control switch settings.
Finally, CEI reviews applicable industry recommendations which are factored into these procedures. This includes Limitorque recommendations, NRC Bulletins and Information Notices, INPO Reports, EPRI Reports and communication with ~other utilities concerning motor-operated valve l
problems.
E.-
Results t-1.
Attached Table documents the results of Item A.
2.
Program:
l l
Item B: Completed. The methodology for establishing and revising control switch settings is appropriate and addresses the recommendations of the I.E. Bulletin.
Item C: CEI will complete the operability testing on or before November 15, 1987.
s I
Item D: Completed. Procedures are in place for both Engineering and i
Maintenance to determine, implement and maintain the correct control switch settings.
l i
w
-y--,
.,m-.
,-..<-r,
.,-,n m-,
7.,_--,
---,.m a
r Attachment PY-CEI/0IE-0206 L Page 5 of 7 Preliminary Motor-Operated valve Data Valve Data Operator Data N
Vendor valve ve'ndor Tjpe Maximum MPL No.
Size, Tyge
~ RPM Functional Description Diff. Pressure 1E51F0001. GE/AMCflOR IRRLING LIMI70RQUE HIGH PRESSURE CORE SPRAY 100 PSID 15", GATE SMB-00 CONDENSATE STORAGE TANK TO' 1750 RPM HPCS PUMP SUCTION 1E22F0004 GE/ ANCHOR DARLING LIMI10RQUE HIGH PRESSURE CORE SPRAY 1575 PSID 12", GATE SB-3 TO REAC20R PRESSURE VESSEL 1700 RPM INJECTOR VALVE 1E22F0010 GEVANCHOR DARLING LIMITORQUE HIGH PRESSURE CORE SPRAY 1575 PSID 10", GICBE SMB-4 SYSTEM PUMP RECIRCUIATION 1730 RPM TO CONDENSATE STORAGE TANK 1E22F0011 GE/ ANCHOR DARLING LIMITORQUE HIGH PRESSUPI CORE SPRAY 1575 PSID 10", GICBE SMB-4 SYSTEM FUMP.DECIRCULATION 1730 RPM TO CONDENSATE STORAGE TANK 1E22F0012 GE/ ANCHOR DARLING LIMI10RQUE HIGH PRESSURE CORE SPRAY 1575 PSID 4",
GATE SB-0 SYSTEM MINIMUM FLOW TO 3400 RPM SUPRESSION POOL 1E22F0015 GE/ ANCHOR DARLING LIMI70RQUE HIGH PRESSURE CORE SPRAY 100 PSID 24", GATE SE-1 SUCTION FROM SUPPRESSION 3450 RPM POOL 1E22F0023 GE/ ANCHOR DARLING LIMI10RQUE HIGH PRESSURE CORE SPRAY 1575 PSID 12", CICBE SMB-4 SYSTE24 TEST 10 SUPPRESSION POOL
Attachment PY-CEI/01E-0206 L Page 6 of 7 Preliminary Motor-Operated Valve Data Valve Data Operator Data Vendor VQlve Vendor Type Maximum MPL No.
Size, Type RPM runctional Description Diff. Pressure IE51r0010 BORG-WARNER LIMI70RQUE REACIOR CORE ISOIATION COOLING 75 PSID 6",
GATE SMB-00 PUMP 70 CONDENSATE STORAGE 1900 RPM TANK ISOIATION VALVE 1E51r0013 BORG-MARNER LIMII0RQUE REACIOR CORE ISOIATION COOLING 1400 PSID 6",
GATE SMB-1 PUMP DISCHARGE VALVE 1E51F0019 ROCKWELL LIMI70RQUE REAC10R CORE ISOIATION COOING 1400 PSID 2",GIDBE SMB-000 MINIMUM FIDW 10 THE 1900 RPM SUPRESSION POOL 1E51r0022 BORG-WARNER LIMITORQUE REACTOR CORE ISOIATION COOLING 1100 PSID 4", GISBE SMB-0 PUMP REIURN TO THE CONDENSATE 1900 RPM STORAGE TANK ISOIATION VALVE 1E51r0031 BORG-NARNER LIMITORQUE REACIOR CORE ISOLATION COOLING 75 PSID 6" GATE SMB-00 SUCTION FROM THE SUPPRESSION 1900 RPM POOL ISOIATION VALVE 1E51r0045 BORG-NARNER LIMITORQUE REACTOR CORE ISOIATION COOLING 1177 PSID 4" GLOBE SMB-0 TURBINE STEAM SUPPLY VALVE 1E51r0046 ROCKWELL LIMI10RQUE REACIOR CORE ISOIATION COOLING 1400 PSID 2", GLOBE SMB-000 PUMP DISCHARGE 'IO AUXILIARY 1900 RPM EQUIPMENT COOIANT IDOP
Attachment PY-CEI/0IE-0206 L Page 7 of 7 I
Preliminary Motor-Operated Valve Data l
Valve Data Operator Data Vendor Valve Vendor Type Maximum MPL No.
Size, Type RPM runctional Description Diff. Pressure 1E51r0063 BORG-WARNER LIMI'IORQUE REACIOR CORE ISOLATION COOLING 741 PSID 10", GATE SMB-1 AND RESIDUAL HEAT REMOVAL SYS, 1900 RPM STEAM SUPPLY ISOIATION VALVE 1E51r0064 BORG-WARNER LIMI'IORQUE REAC'IOR CORE ISOLATION COOLING 1177 PSID 10", GATE SB-1 AND RESIDUAL HEAT REMOVAL SYS.
3450 RPM STEAM SUPPLY ISOLATION VALVE 1E51r0068 BORG-WARNER LIMI'IORQUE REACIOR CORE ISOLATION COOLING 30 PSID 12", GATE SMB-0
'IURBINE EXHAUST 'IO SUPPRESSION 1900 RPM POOL ISOIATION 1E51r0076 ROCKWELL LIMI'IORQUE REACIOR CORE ISOIATION COOLING 1177 PSID 1", GICBE SMB-000 STEAM WARMUP LINE ISOIATION 1700 RPM AND BYPASS FOR 1E51r0063 1E51r0077 ROCKWELL LIMI'IORQUE REACIOR CORE ISOLATION COOLI':JG 30 PSID
- 1. 5",GIDBE SMB-000 SYSTEM: VACUUM RELIEF FOR 1700 RPM REACIOR CORE ISOIATION COOLING
'IUBINE EXHAUST 1E51r0078 ROCKWELL LIMI'IORQUE REACIOR CORE ISOIATION COOLING 30 PSID 2", GIDBE SMB-000 SYSTEM: VACUUM RELIEF FOR 1700 RPM REACIOR CORE ISOLATION COOLING
'IURBINE EXHAUST 1E51r0510 GE LIMI'IORQUE REACIOR CORE ISOIATION COOLING 1177 PSID 4",
GATE SMB-000
'IURBINE TRIP THROITLE 1900 RPM