ML20108B549
| ML20108B549 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 10/22/1984 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NCR-2551, NUDOCS 8411160100 | |
| Download: ML20108B549 (2) | |
Text
P o
u, TENbtgggggVALLEY AUTHORITY AStrhNo6cd Eksisscc 374o 400 Ch'sth et Tower II e
BLRD-50-438/83-63 BLRD-50-439/83-57 U.S. Nuclear Regulatory Commissicn Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, Suite 3100 Atlanta, Georgia 30323
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - ORIENTATION OF ASCO SOLEN 0ID -
OPERATED VALVES - BLRD-50-438/83-63, BLRD-50-439/83 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector Linda Watson on November 30, 1983 in accordance with 10 CFR 50.55(e) as NCR 2551. This was followed by our interim report dated December 28, 1983 Enclosed is our final report.
If you have any que. m ons concerning this matter, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Manager Nuclear Licensing Enclosure cc:
Mr. Richard C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure) l Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 l
8411160100 841022 OPtycqbCQPg PDR ADOCK 05000438 S
PDR An Equal Opportunity Employer
ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 ORIENTATION OF ASCO SOLEN 0ID-OPERATED VALVES NCR 2551 10 CFR 50.55(e) REPORT BLRD-50-438/83-63, BLRD 50-439/83-57 FINAL REPORT Description of Deficiency Pilot solenoid valves are used in the air line to a pneumatic control valve air diaphragm for the purpose of relieving the pressure on the diaphragm to allow a spring to force the control valve to its failure mode.
The solenoids are normally mounted on the control valve by the control valve manufac turer. Certain solenoid models manufactured by the Automatic Switch Company ( ASCO) require a specific mounting orientation to assure correct operation. Several valves were found installed at Bellefonte with the solenoids not oriented in the required position. Specifically, the control valve manufacturer (Copes Vulcan, Incorporated) had assumed the control valve would be installed in the piping with its diaphragm actuator vertical and oriented the solenoid for this installation. Unfortunately, due to surrounding hardware interferences, some of the control valves could not be installed with their actuators vertical but instead were installed with the actuators horizonta). As a, consequence, the solenoids ara not oriented to permit proper operation.
The cause of the deficiency can be attributed to a failure by the designers to recognize that certain pilot solenoid valves have specific orientation limitations and that either the control valves should have been installed in the piping to correctly crient the solenoid valves or solenoid mounting brackets should have been redesigned as required to correctly crient the solenoids.
Safety Implications Orientation of control valves in a position other than that required by the vendor due to solenoid positioning could result in the inability of the valve to properly function. Further, this failure to operate may not be apparent to the operator so that corrective measures could be taken in a timely manner. Therefore, this deficiency could adversely affect operation of the plant.
Corrective Action Mounting brackets for the solenoids were either redesigned or remounted to give correct solenoid orientation. The manufacturer's valve drawings were revised as necessary to instruct TVA's Office of Construction (CONST) of the mounting bracket redesign or orientation diange by engineering change notice (ECN) 2878. Final drawing issue under ECN 2878 was completed May 8,1984.
CONST work will be completed by August 1, 1985.
l I
)
!l Ou s&n w w u
~
Tha acticn t _ ken to prevent recurrenca involved instructing the dtsigntes responsible for determining control valve orientation in piping to denote on all future control valve manufacturer's drawings the position that the valve will assume when installed in the piping. This will allow the manufacturer to correctly crient the accessories (including pilot solenc:ds) based on the actual valve installation rather than an " assumed" installation.
--O+
"')
k-e y
,p I
.s O
I a.
i
':-4abedi45#:-[-t .
%%3d d
[. ws'w.we Q, w.. d
-