ML19276E888
| ML19276E888 | |
| Person / Time | |
|---|---|
| Site: | Catawba, Perkins, Cherokee  |
| Issue date: | 03/16/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Dail L DUKE POWER CO. |
| References | |
| NUDOCS 7903210575 | |
| Download: ML19276E888 (1) | |
Text
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UNITED STATES (p >s as49'o,,
NUCLE AR REGULATORY COMMISSION t
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101 M ARIETT A STREET,N.W.
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- E ATLANT A, oEORotA So303 MAR 161979 o,%.....#
In Reply Refer To:
R11:JP0 50-413, 50-414 50-488, 50-489 50-490, 50-491 50-492, 50-493 Duke Power Company Mr. L. C. Dail, Vice President Attn:
Design Engineering P. O. Box 33189 Charlotte, Not u. C:r-'ina 28242 Gentlemen:
The enclosed IE Circular 79-04 is f orwarded to you for infomation.
If there are any questions related to your understanding of the sug this office.
actions, please centact
~ t James P. O' Reil y g
Director
Enclosure:
IE Circular No. 79-C4 cc w/ enc 1:
D. G. Beam, Project Manager Catawba Nuclear Station P. O. Box 223 27910 Clover, South Carolina J. T. Moore, Project Manager Cherokee Nuclear Station P. O. Box 422 29340 Gaffney, South Carolina 790321o5'l5' 9
UNITED STATES NUCLT dl REGULATORY C0!aCSSION OFFICE CF INSFECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 March 16, 1979 IE Circular No. 79-Oh LOOSE LOCKING NUT CN LIMITORQUE VALVE OPEFATOPS Description of Circu= stances:
On Decerber 8,1978, Fort Calhoun Station Unit No. I reported that 30 out of 65 Limitorque Type SMB valve operators did not have the locking nut fastened securely in acccrdance with the manufacturer's reco==endation.
If this locking nut is not secure it can loosen and allow the stem nut to cove axially to the point that the splines are The licensee disengaged; resulting in a loss of drive to the valve stem.
reported that several locking nuts were slightly loose but in no instance had the ste= nut backed out enough to affect the operation of the valve.
This licensee was made aware of the potential problem by a letter of July 28,1978, from the NSSS supplier, Combustion Engineering, Inc.
Other plants have reported similar findings.
On April 27, 1977, Davis-Eesse Nuclear Fover Station Unit No.1, reported that two valve operability failures had been caused by locking nuts loosening and falling off.
During the ensuing inspection program a totcl of 65 out of 1k4 safety related valve operators required staking. Arkansas Nuclear One (ANO), Unit 2, reported on June 29, 1978, that several valve operators required staking. A subsequent inspection at ANO Unit 2 was made by an IE inspector who identified records that 15 out of 17 SM3 cperators provided by the NSSS supplier (Co=bustion En6 neering Inc.) required 1
st aking. Valve operability failures, resulting fro = loosened locki'g nuts, have also been reported by Cooper Nuclear Station (Unusual Event heport 75-5), Browns Ferry Unit 2 report of March 6,197L and Three Mile Island Nuclear Station Unit 1 reports of March 13, 1976 and October 20, 1976.
The corrective action ty the licenset in each case was to stake the locking nut.
In Jur.e 1978, the Limiterque Corporation issued a supple =ent to the October 1977 f ecue of the Type SM3 Instruction and Maintenance Manual SMBI-170 that called for the cri= ping or attking of the locking nuts.
The 1971 issue of the manual had statements for critping and staking of the lock nuts incorporated into the manual. The ste nu' specification drawing provided by Limitorque for Unit Types SMP-000, SMB-00, SM3-0, SMB-1, SML-2, SMB-3, and SM3 L directs the custo=er to a Limitorque 1 of 2 00 7903210092
IE Circular No. 79-OL March 16, 1979 Drawing No. 21 L97-0009-3 for instructions on staking the 10cking nut ;
the specification drawing for the SMB-5 unit has a reference to Limitorque Drawing No. 21 L97-0010-3 for staking instructions.
Pennsylvania Power and Light Company (PF&L) informed the FRC that the generic proble= cf failure to stake locking nuts exists with Limitorque Type SMC valve operators and Type SMB operaters.
FF&L Co. vas advised of the proble= by Bechtel Corporation. The infor=ation was submitted to the NEC on March 2,1979 as a deficiency at the Susquehanna Stea Electric Station. The Type SMC Instruction and Maintenance Mar.ual SMCI-OL-78 and Drawing No. 21 L97-0013-3 provide directions for securing the locking nut.
All holders of construction permite and operating licenses should be aware that the potential for valve operator failure exists if the locking nut is not adequately aecured. The reco== ended action is to survey all ir.ctalled Limitorque Operator Types SMB-000 through SMB-5 and Type Sf:0 to determine that the locking nut is secure and to verify that asse=bly and maintenance instructions contain directions for securing the locking nut either by staking, per the vendor's reco==endation, or another acceptable manner.
No written recpcnse to this Circular is required.
If you require additional information regarding this subject, centact the Director of the appropriate NLC Regional Office.
Enclosure:
Lir t Of IL Cf reulars Issued in the Lact Twelve Months 2 of 2
.t
IE Circular No. 79-Oh March 16, 1979 LISTING OF IE CIRCULARS ISSLTD IN LAST TWELVI' M0!."IHS Date Issued To Circular Subject of Issue No.
s.
76-01 Lots of Well Logging h/5/78 All Holdere of Well Logging Source Source Licenses 78-02 Proper Lubricating Oil h/20/78 All Holders of Beactor OLs or for Terry Turbines cps 78-03 rackaging Greater Than 5/12/78 All Holders of Reactor OLs, cps, Type A Quantities of Fuel Cycle, Lov Specific Activity Priority I Material Radioactive Material and Waste Disposal for Transport Licenses 76-CL Installation Error That 5/15/78 All Holders of Reactor OLs or Could Prevent C1csing of cps Fire Doors 78-05 Inadvertent Safety injecticn 5/23/78 All Holders of Beactor OLs or During Cooldovn cps 78-06 Potential Co==on Mode 5/23/78 All Holders of Reactor OLs or Flooding of ECCS Equipment cps Rocc.s at BVP Facilities 76-07 Dar. aged Co=ponents of a 5/31/78 All Holders of Beactor OLs or bergen-Paterson Series cps 25000 Hydraulic Test Stand 78-08 Environ = ental Qualification 5/31/78 All Holders of Beactor OLs or of Safety Related Equip =ent cps at Nuclear Power Flanta Ibelosure Page 1 of 3
b IE Circular No. 79-04 March 16, 1979 LISTING OF IE CIRCULARS ISSUED IN LAST TWELVE MONTHS Circular Subject Date of Issued To No.
Issue 1.
78-09 Arcing of General Electric 6/5/78 All Holders of Company Size 2 Contactors cps 78-10 Control of Sealed 6/14/78 All Medical Sources Used in Licensees in Radiation Therapy Categories C and G1 78-11 Recirculation M-G 6/15/78 All Holders of Set Overspeed Stops BWR OLs or cps 78-12 HPCI Turbine Control 6/30/78 All Holders of Valve Lift Rod Bending BWR OLs or cps fer plants with HPCI Terry Turbine 78-13 Inoperability of Multiple 7/10/78 All Holders of Service Water Pumps Reactor OLs and cps except for plants located in: AL, AK, CA, FL, GA, LA, MS, SC 78-14 HPCI Turbine Reversing 7/12/78 All Holders of BWR Cha=ber Hold Down Bolting OLs or cps for plants with a HPCI Terry Turbine excepting Duane Arnold and Monticello 78-15 Checkvalves Fail to 7/20/78 All Holders of Close In Vertical Reactor OLs or cps Position Enclosure Page 2 of 3
IE Circular No. 79-04 March 16, 1979 LISTING OF IE CIRCULARS ISSUED IN LAST TWELVE M0bTHS Date of Issued To Circular Subject Issue No.
78-16 Limitorque Valve 7/26/78 All Holders of Reactor OLs or Actuators cps 7-17 Inadequate Guard Training /
10/13/78 All Holders of Qualification and Falsified and applicants for Reactor OLs.
Training Records 7-18 UL Fire Test 11/6/78 All Holders of Reactor OLs or cps 78-19 Manual Override (Bypass) 12/28/78 All Holders of of Safety Actuation Signals cps 79-01 Administration of 1/12/79 All Medical Unauthorized Byproduct Licensees except Material to Humans Tel. therapy Medical Licensees and each Radiopharmaceutical Suppliers 79-02 Failure of 120 Volt Vital 2/16/79 All Holders of AC Power Supplies Reactor OLs and cps 79-03 Inadequate Guard Training-2/23/79 All Holders of Qualification and Falsified and applicants Training Records for Special Nuclear Material Licenses in Safeguards Group 1 Enclosure Page 3 of 3