(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
|
---|
Category:GENERIC LETTERS & IE LETTERS TO MULTIPLE PLANTS.
MONTHYEARML20151H0271982-01-27027 January 1982 IE Info Notice 82-02, Westinghouse Nbfd Relay Failures in Reactor Protection Sys at Certain Nuclear Power Plants ML20151H0201982-01-22022 January 1982 IE Info Notice 82-01, Auxiliary Feedwater (AFW) Pump Lockout Resulting from Westinghouse W-2 Switch Circuit Mod ML20151H0231981-12-23023 December 1981 IE Info Notice 81-39, EPA Cross Check Program - Low Level Radioiodine in Water Intercomparison Study ML20151H0191981-12-15015 December 1981 IE Info Notice 81-37, Unnecessary Radiation Exposure to Public & Workers During Events Involving Thickness & Level Measuring Devices ML20151H0151981-12-0303 December 1981 IE Info Notice 81-36, Replacement Diaphragms for Robertshaw Valve(Model No. VC-210) ML20151H0131981-11-16016 November 1981 IE Info Notice 81-34, Accidental Accuation of Prompt Public Notification Sys ML20151H0111981-11-0909 November 1981 IE Info Notice 81-33, Locking Devices Inadequately Installed on Msivs. W/O List of Recently Issued Info ML20151H0081981-09-28028 September 1981 IE Info Notice 81-30, Velan Swing Check Valves ML20151D7471981-09-0303 September 1981 IE Info Notice 81-28, Failure of Rockwell-Edward Msivs ML20151A6701980-12-18018 December 1980 IE Bulletin 80-17 Suppl 4, Failure of Control Rods to Insert During Scram at Bwr ML20150F8381980-11-26026 November 1980 IE Info Notice 80-29,Suppl 1, Broken Studs on Terry Turbine Steam Inlet Flange ML20125E3171980-01-0707 January 1980 Table C-1 to Be Included W/App C,Encl 4 of IE Bulletin 79-01B, Environ Qualification of Class IE Equipment 1982-01-27
[Table view]Some use of "" in your query was not closed by a matching "". Category:NRC INFORMATION NOTICE
MONTHYEARML20151H0271982-01-27027 January 1982 IE Info Notice 82-02, Westinghouse Nbfd Relay Failures in Reactor Protection Sys at Certain Nuclear Power Plants ML20151H0201982-01-22022 January 1982 IE Info Notice 82-01, Auxiliary Feedwater (AFW) Pump Lockout Resulting from Westinghouse W-2 Switch Circuit Mod ML20151H0231981-12-23023 December 1981 IE Info Notice 81-39, EPA Cross Check Program - Low Level Radioiodine in Water Intercomparison Study ML20151H0191981-12-15015 December 1981 IE Info Notice 81-37, Unnecessary Radiation Exposure to Public & Workers During Events Involving Thickness & Level Measuring Devices ML20151H0151981-12-0303 December 1981 IE Info Notice 81-36, Replacement Diaphragms for Robertshaw Valve(Model No. VC-210) ML20151H0131981-11-16016 November 1981 IE Info Notice 81-34, Accidental Accuation of Prompt Public Notification Sys ML20151H0111981-11-0909 November 1981 IE Info Notice 81-33, Locking Devices Inadequately Installed on Msivs. W/O List of Recently Issued Info ML20151H0081981-09-28028 September 1981 IE Info Notice 81-30, Velan Swing Check Valves ML20151D7471981-09-0303 September 1981 IE Info Notice 81-28, Failure of Rockwell-Edward Msivs ML20150F8381980-11-26026 November 1980 IE Info Notice 80-29,Suppl 1, Broken Studs on Terry Turbine Steam Inlet Flange 1982-01-27
[Table view]Some use of "" in your query was not closed by a matching "". Category:TEXT-INSPECTION & AUDIT & I&E CIRCULARS
MONTHYEARML20215G9881987-04-10010 April 1987 Notice of Nonconformance from Insp on 870223-27 & 0324 ML20206D8851987-04-0808 April 1987 Notice of Nonconformance from Insp on 870309-11 IR 05000354/19870101987-04-0707 April 1987 Insp Rept 50-354/87-10 on 870316-20.No Violations Noted. Major Areas inspected:post-accident Monitoring Sys Conformance W/Rev 2 to Reg Guide 1.97.Open Item Identified Re Identification of Category 2 Equipment ML20206M7981987-04-0707 April 1987 Insp Rept 50-312/86-41 on 861201-870212.Unresolved & Open Items Identified.Major Areas Inspected:Activities Supporting Restart & Ensuring Safe Operation of Plant After Restart, Including Stated Phases of Sys Review & Test Program ML20206D8361987-04-0707 April 1987 Insp Rept 99900271/87-01 on 870127-29.No Violations, Nonconformances or Unresolved Items Noted.Major Areas Inspected:Corrective Action Re Intermittent Failures & Review of Test Results on Three Failed Transmitters ML20215G9961987-04-0606 April 1987 Insp Rept 99900383/87-01 on 870223-27.Nonconformance Noted: Pressure Gauge Not Calibr for Over 0-30 Psig Range & 30 Psig Pressure Test of O-ring Seals Failed Pressure Drop Requirement ML20206F9681987-04-0303 April 1987 EN-87-029:on 870408,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $50,000 Will Be Issued.Action Based on Loss of Approx 141,000 Gallons of Water from Spent Fuel Pools Through Fuel Transfer Canal IR 05000327/19870051987-04-0303 April 1987 Insp Repts 50-327/87-05 & 50-328/87-05 on 870119-23.No Violations or Deviations Noted.Major Areas Inspected:Review & Evaluation of 13 Employee Concern Task Group Final Sequoyah Element Repts IR 05000327/19870061987-04-0303 April 1987 Design Calculation Review Insp Repts 50-327/87-06 & 50-328/87-06 on 870202-13.No Violations Noted.Major Areas Reviewed:Adequacy of Util Design Calculation Review Program & Extent Program Augments Design Baseline Re Restart ML20206E8121987-04-0101 April 1987 Insp Repts 50-445/86-26 & 50-446/86-22 on 860901-1031. Violations & Deviations Noted:Cable Pulling Ropes Left in Unit 1 Conduits & Cable Trays & Failure of Inspector to Write Memo Documenting Nonconforming Condition IR 05000445/19860261987-04-0101 April 1987 Insp Repts 50-445/86-26 & 50-446/86-22 on 860901-1031. Violations & Deviations Noted:Cable Pulling Ropes Left in Unit 1 Conduits & Cable Trays & Failure of Inspector to Write Memo Documenting Nonconforming Condition ML20206D9141987-04-0101 April 1987 Insp Rept 99901085/87-01 on 870309-11.Nonconformances Noted: Failure to Administer Exam by Level III Examiner or Designated Representative & 1986 Eye Exams for Listed Level II Examiners Missing IR 05000327/19860681987-03-31031 March 1987 Insp Repts 50-327/86-68 & 50-328/86-68 on 861201-12 & 870112-23.Violations Noted:Licensee Failed to Assure That Applicable ASME Code Requirements Included in Procurement of Specific safety-related Code Class Equipment ML20215E4831987-03-31031 March 1987 EN-87-026:on 870331,order Suspending Power Operation & Order to Show Cause Issued to Util Due to Discovery That Control Room Staff Have Been Sleeping During Various Shifts.Related Documents Encl ML20206D1901987-03-31031 March 1987 Insp Rept 99901088/87-01 on 870121.Major Areas Inspected: Corrective Action Taken Re 860917 Part 21 Rept Concerning Potential Problem in Pressure Transducers ML20205R4601987-03-30030 March 1987 Insp Rept 99900762/87-01 on 870203-04.No Noncompliances or Violations Noted.Major Areas Inspected:Allegations Re Use of Uncertified Welders & Possible Falsification of Welding Records.Two of Nine Allegations Substantiated IR 05000267/19870041987-03-27027 March 1987 Insp Rept 50-267/87-04 on 870126-30.No Violations Noted. Major Areas Inspected:Program to Maintain Qualification of Electrical Equipment Per 10CFR50.49.Potential Enforcement/ Unresolved Items & Open Items of Program Listed IR 05000277/19870061987-03-23023 March 1987 Fitness for Duty Program Insp Repts 50-277/87-06 & 50-278/87-06 on 870202-06.Observations Noted:Util Written Policies Do Not Address Features of Commission Policy Statement or EEI Guide & No Overall Audit Performed ML20205H3661987-03-23023 March 1987 EN-87-023:on 870326,notice of Violation & Proposed Imposition of Civil Penalties in Amount of $50,000 Will Be Issued to Licensee.Action Based on Failure to Obtain Prior NRC Approval of Criteria Change for Reactor Coolant Flow ML20205H2411987-03-23023 March 1987 EN-87-022:on 870326,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $12,500 Will Be Issued to Licensee.Action Based on Numerous Violations of NRC Requirements Re Overexposure to Workers ML20207S2811987-03-17017 March 1987 Notice of Violation from Insp on 870126-30 ML20207S2921987-03-17017 March 1987 Notice of Nonconformance from Insp on 870126-30 IR 05000275/19860331987-03-17017 March 1987 Insp Repts 50-275/86-33 & 50-323/86-31 on 861215-19. Deficiencies Noted.Major Areas Inspected:Implementation Program for Establishing & Maintaining Environ Qualification of Electrical Equipment Important to Safety ML20205D2131987-03-16016 March 1987 Insp Repts 50-445/86-22 & 50-446/86-20 on 860701-0831. Violations & Deviations Noted:Stainless Steel & Carbon Steel Stored in Outside Areas W/Improper Protective End Coverings & Records of Heat Treatment Not Available for Disc Inserts ML20207R5751987-03-13013 March 1987 EN-86-074A:on 870313,order Issued Imposing Civil Penalties in Amount of $3,000 to Univ of Utah,Based on Transportation, Health Physics,Safeguards & Operations Violations Noted in 860930 Enforcement Notification EN-86-074 ML20207R3341987-03-11011 March 1987 EN-87-019:on 870311,notice of Violation & Proposed Imposition of Civil Penalties in Amount of $50,000 Will Be Issued for Licenses.Action Based on Three Examples of Degraded Vital Area Barriers ML20207R4851987-03-0909 March 1987 EN-87-017:on 870312,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $25,000 Will Be Issued to Util Based on Failure to Provide Adequate Design Control to Ensure Emergency Feedwater Pump Operability ML20207R3701987-03-0909 March 1987 EN-87-015:on 870312,notice of Violation & Proposed Imposition of Civil Penalties in Amount of $50,000 Will Be Issued for License.Action Based on Violation of Tech Spec Re ECCS Subsystems ML20207S3331987-03-0606 March 1987 Insp Rept 99901079/87-01 on 870126-30.Violation Noted:Two Nuclear Purchase Orders Accepted & Fulfilled W/O 10CFR21 Program in Effect.Nonconformance Noted:Master Ammeter Had No Sticker to Identify Calibr Status IR 05000327/19860701987-03-0303 March 1987 Insp Repts 50-327/86-70 & 50-328/86-70 on 861208-12.No Programmatic Deficiencies W/Regard to Facility Maint of Environmentally Qualified Equipment Identified.Major Areas Inspected:Maint Program & Previous Insp Items ML20207R0301987-03-0303 March 1987 EN-87-014:on 870306,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $50,000 Issued to Licensee.Action Based on Failure to Establish & Maintain Operability of Nuclear Svc Water Sys ML20212F0181987-03-0202 March 1987 Notice of Violation from Insp on 870112-14 ML20212F0331987-02-27027 February 1987 Insp Rept 99901080/87-01 on 870112-14.Violation Noted: Failure to Adopt Procedure to Evaluate or Rept Defects Discovered in Motors Supplied to Customers Under Part 21 ML20212B1991987-02-26026 February 1987 EN-86-029A:on 870226,order Imposing Civil Monetary Penalty in Amount of $50,000 Issued to Licensee Based on Licensee 860703 Response to 860501 Notice of Violation & Proposed Imposition of Civil Penalty.Section I Violation Did Occur ML20212H0491987-02-26026 February 1987 EN-87-012:on 870303,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $75,000 Will Be Issued Based on Violations in Areas of Facility Design,Maint & Mods IR 05000498/19860421987-02-20020 February 1987 Engineering Assurance Program Insp Repts 50-498/86-42 & 50-499/86-42 on 861215-19.Major Areas Inspected:Task 84-4, Separation & Fire Protection Criteria & Task 85-4, High Energy Line Break Analysis ML20211P4311987-02-19019 February 1987 EN-87-010:on 870224,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $25,000 Will Be Issued to Util Based on Multiple Violations Re Safeguards Info Protection Program ML20212E7581987-02-18018 February 1987 Insp Rept 99900507/86-01 on 861201-05.No Violations or Noncompliance Noted.Major Areas Inspected:Status of Previous Findings,Dedication of Commercial Grade Items Overview & 10CFR21 Evaluation & Reporting Review ML20211B8481987-02-13013 February 1987 Notice of Nonconformance from Insp on 870112-14 ML20211B8161987-02-13013 February 1987 Notice of Violation from Insp on 870112-14 ML20211B9021987-02-13013 February 1987 Insp Rept 99900816/87-01 on 870112-14.Violation Noted:Mfg Did Not Specify Application of Part 21 Requirements on Listed Purchase Orders.Nonconformances Noted:Quality Sys Program Not Invoked on Listed Orders & Order Data Differed ML20211B5511987-02-12012 February 1987 EN-85-084A:on 851213,notice of Violation & Proposed Imposition of Civil Penalties in Amount of $900,000 Will Be Issued to Licensee.Action Based on 850609 Failure of Auxiliary Feedwater Sys to Perform Intended Function ML20210U0531987-02-10010 February 1987 Insp Rept 99901067/86-01 on 861103-07.Nonconformance Noted: NDE Technician Certified W/O Attaining Passing Grade on Magnetic Particle Exam,Per Procedure QC-2.Data Sheets Encl IR 05000321/19860351987-02-0707 February 1987 Equipment Qualification Insp Repts 50-321/86-35 & 50-366/86-35 on 861103-07.Major Areas Inspected:Program for Establishing & Maintaining Qualification of Electric Equipment Per 10CFR50.49.Five Deficiencies Noted ML20210E9371987-02-0606 February 1987 Insp Rept 99900015/86-01 on 861020-29.Noncomformance Noted: Mechanical & Chemical Testing Svc Performed by Outside Lab W/O Advising Lab of 10CFR21 Requirements & Incorrect Audits of Vendors ML20210E9201987-02-0606 February 1987 Notice of Nonconformance from Insp on 861020-24 IR 05000508/19860121987-02-0606 February 1987 Insp Rept 50-508/86-12 on 860915-1215.No Violations Noted. Major Areas Inspected:Readiness Review Program Module C3-01, Earthwork & Followup on Insp Repts 50-508/86-10 & 50-508/86-11 ML20210A9591987-02-0505 February 1987 Notice of Nonconformance from Insp on 861202-05 ML20210B0011987-02-0404 February 1987 Insp Rept 99900835/86-01 on 861203-05.Nonconformances Noted:Controls Necessary to Ensure Charging Motors Purchased from Subvendors Conform to Drawings Not Established ML20210P9041987-02-0303 February 1987 EN-87-005:on 870209,notice of Violation & Proposed Imposition of Civil Penalty in Amount of $50,000 Will Be Issued to Util Based on Ofc of Investigations Investigation Re Employment Termination of Technician 1987-04-08
[Table view]Some use of "" in your query was not closed by a matching "". |
Text
.
4 .
( I
(
SSIN No.: 6835
8103300413 IN 81-28 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF-INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 September 3, 1981 -
IE INFORMATION NOTICE NO. 81-28: FAILURE OF ROCKWELL-EDWARD MAIN STEAM ISOLATION VALVES Description of Circumstances:
There have been several recent mechanical failures of the "Rockwell-Edward Flite Flow Stop Valve," a "Y" pattern globe valve made by Rockwell International, used for main steam isolation valves (MSIV) at some BWR facilities. Operating BWR facilities using this valve include Brunswick Unit 1 and 2, Cooper, Duane Arnold, Fitzpatrick, Hatch Unit 2, and Vermont Yankee. Of the seven total reported mechanical failures, five occurred at Brunswick Unit 2 and one each occurred at Brunswick Unit 1 and Hatch Unit 2.
The valve components that have failed are shown in Figure 1. The piston assembly is attached to the main disk (2) by thread engagement and then restrained from unwinding by pin (4). The stem disk (1) is also attached to the stem (6) by thread engagement tightened to 1050 ft-lb torque specifications with an anti-rotation restraint provided by pin (3). The valve is closed primarily by spring forces. The valve is installed so that reactor steam pressure works to seat the main disk. The stem disk provides pressure equalization action to reduce over-seat load for opening the main disk against system pressure.
The failures that have occurred involved a mechanical separation of valve internals. This separation was either at the stem-to-stem-disk threaded i
l' connection or at the main-disk-to piston threaded connection. Either failure permits the main disk to be free of the stem. The failure in either mode results from failure of the threaded connection, which in some cases is caused by vibration-induced rotation of the disk so that it becomes disconnected from its threaded mate. Such rotation is believed to be caused by or aided by the propensity of steam flow to produce vibration and to create turning forces on valve internal components when antirotation restraint is inadequate due to .
a failed or missing pin. Other contributing causes are believed to result from reassembly of the valve after disassembly at the site; such reassembly may have included inadequately torqued connections and failure to properly install the pins.
Also, an examination of spare parts at the Brunswick site showed that the thread dimensions on the stems and stem disks did not meet drawing tolerances.
The individual failures are described below in chronological order. i
- 1. In January 1976, the Brunswick Unit 2 "D" steam line inboard valve main disk separated from the piston. There was nc evidence that pin (4) was installed, w
8/0V600 </13] g
~
f *
- IN 81-28 September 3, 1981 Page 2 of 2
- 2. On January 30, 1979, the Brunswick Unit 2 "A" steam line inboard valve stem disk separated from the stem. A square pin was used in the round hole at point (3). The corners of the pin experienced high stress, thereby causing cracking of the pin.
- 3. On January 15, 1981, the Brunswick Unit 2 "C" steam line outboard valve main disk separated from the piston. There was no evidence that pin (4) was
- ever inserted. This was deduced from finding the hole not deformed and no sign of a plug weld.
- 4. On March 5, 1981, the Hatch Unit 2 "A" steam line inboard valve stem disk separated from the stem. Pin (3) was not fully inserted.
- 5. On March 30, 1981, the Brunswick Unit 1 "C" steam line outboard valve stem disk separated from the stem. Pin (3) failed and was not recovered.
i 6. On July 2, 1981, the Brunswick Unit 2 "C" steam line inboard valve stem disk separated from the stem. Pin (3) was not properly installed.
- 7. On July 18, 1981, the Brunswick Unit 2 "D" steam line inboard valve main disk separated from the piston. Pin (4) was not fully inserted.
These failures have raised concerns regarding (1) the capability of the valve to perform its required safety function and (2) increased challenges to safety systems. However, it is noted that the failures to date have resulted in the main disk going closed (i.e., not cocking open) with some uncertainty only as to its leak tightness.
t Detailed investigation of the July failures at Brunswick Unit 2 led to the i
preliminary findings of possible excessive vibrations on valve internals from steam flow turbulences created by the piping direction changes. In addition, there was evidence of loose thread connections. Further investigations and evaluations are currently in progress. Preliminary corrective actions by the licensee include increasing the stem pin size from 5/16-inch to 3/8-inch, using three pins instead of one or two pins, and increasing the hole depth 1/8-inch into the stem. In addition, corrective actions for the main-disk-to piston connection include adding an extra pin (of the same 1/2-inch size) and increasing the hole depth by 1/8-inch.
This information is provided as notification of a potentially significant matter that is still under review by the NRC staff. In case the continuing NRC review finds that specific licensee actions would be appropriate, an IE circular or bulletin may be issued. In the interim, we expect that licensees will review this information for applicability to their facilities.
I No written response to this information is required. If you need additional information regarding this matter, please contact the Director of the appropriate i NRC Regional Office.
Attachments:
- 1. Figure 1
- 2. Recently issued IE Information Notices
}
(
- 1. STEM DISK
- 2. MAIN DISK
- 3. ANTIR0TATION PIN - STEM DISK TO STEM
- 4. ANTIR0TATION PIN - MAIN DISK TO PISTON
- 5. STELLITED DISK GUIDES, 3 RIBS,120' APART (OUT OF SHOWN VIEW)
- 6. STEM p
i k 2 s N, N
k k /
e- N % i 4 N
n,N x>: y $
> . N h)M~ m
/-
g,,,,;,y .~ /4 *
, w ,/,,\
~
SEAT & OtSK .j MAIN DISK ASSEMBLY OF ROCKWELL-EDWARD FLITE FLOW STOP VALVE G