ML20205C929

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Part 21 & Deficiency Rept Re Valves Installed Opposite to Direction of Flow,Per 10CFR21 & 50.55 Requirements.Item Being Tracked by MTS EAI B-5115 & Scheduled for Completion 881030
ML20205C929
Person / Time
Site: Vogtle Southern Nuclear icon.png
Issue date: 10/18/1988
From: Rice P
GEORGIA POWER CO.
To:
NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
REF-PT21-88-118-000, RTR-NUREG-0302, RTR-NUREG-302 GN-1500, PT21-88-118, PT21-88-118-000, NUDOCS 8810270022
Download: ML20205C929 (6)


Text

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, f Georgia R:wer Cor pany

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P.D. w . Georgia Power  !

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October 18, 1988

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j U. S. Nuclear Regulatory Commission '

, ATTN: Document Control Desk File: X78G03-M144

Washington, D. C. 20555 Log
GN-1500 l I

Reference:

Vogtle Electric Generating Plant - Unit 2; 50-425  !

Valves Installed Opposite to Direction of Flow I

, GPC Letter GN-1466 dated 6/29/88 In the referenced letter, Georgia Power Company notified the NRC of a potentially reportable condition involving certain Unit 2 valves <

which were inst 41ed opposite to the direction of flow. Georgia Power [

! Company has comy.w w its reportability evaluation on this subject t

and has determined that a reportable condition as defined by the l l reporting requirements of 10 CFR Parts 21 and 50.55(e) does exist. }
Based upon NRC guidance in NUREG-0302, Revision 1, and other NRC  ;

! correspondence, Georgia Power Company is reporting this condition  !

4 pursuant to the reporting requirements of 10CFR50.55(e). A sumary l j of our evaluation for Unit 2 is attached.  !

4 This correspondence contains no proprietary information and may be f;

! placed in the NRC Public Document Room.

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1 740 P. D. Rice

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xc: USRNC - Region II Suite 2900 l 101 Phrtetta Street, N.W. i Atlanta, GA 30323 l

H. G. Baker D. R. Altman C. W. Hayes  !

1 J. P. Kane J. A. Bailey R. W. McManus 2 R. H. Pinson G. Bocxhold, Jr. Sr. Resident (NRC)

E. D. Groover G. R. Frederick D. H. Smith (OPC)

C. T. Moore J. E. Swartzwelder J. E. Joiner (TSLA)

! R. A. Thomas A. B. Gallant NORMS j C. K. McCoy I

es10270022 891010 b

! POR ADOCK 05000425 <}(6 s PCC yg l

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EVALUATION OF A POTENTIALLY REPORTABLE CONDITION VALVES INSTALLED OPPOSITE TO DIRECTION GF FLOW ,

f Initial Report: On June 1,1988, Mr. C. W. Hayes, the Vogtle Quality  !

Assurance Manager, notified Mr. Charles Patterson of the USNRC-Region II, of a potentially reportable condition under  ;

10CFR50.55(e). The potentially reportable condition concerned certain ,

Unit 2 valves installed opposite to their required orientation relative l to the direction of flow.

[

Initial Condition: Piping and Instrument Diagrams (P&ID's) show  ;

the flow direction in each process ifne and check valve. The isometric drawings are the fabrication and installation drawings for the piping  !

systems and provide flow arrows for system flow. Construction then  ;

installs the valves with respect to the direction of flow as indicated e on the isometric drawings. l During system flushing and start-up testing three sets of three valves I were discovered to have been installed opposite to the direction j of the system fluid flow in Unit 2. During system flushing three t Dresser Industries one-inch check valves were found to b2 installed in the wrong direction. This occurred due to the vendor, Dresser Industries, shop stamping the flow arrows on the valves in the wrong i direction. This led to the installation of the valves in the direction '

opposite to the direction of system flow. Six valves were found I during start-up testing to be installed opposite to the direction of system flow. The flow arrows on the associated isometrics for I three of the valves ware not shown or were shown incorrectly. The i flow direction shown on the P&ID's was correct. The other three '

valves were Valcor solenoid valves installed in the wrong direction  !

by construction. The flow direction shown on both the PAID's and  :

!sometrics was correct, but a flow arrow was not shown on the valve. l Engineering Evaluation: Dresser Industries was questioned as to the cause and extent of the check valves having the flow arrows stamped  !

in the wrong direction. Their response dated June 13, 1988, stated {

that the three valves were part of a four valve production order.

However, only three of the four valves were shipped to Plant Vogtle.

The fourth valve was rejected during hydrotest and was not shipped.  :

These valves are Dresser type 7440W. The root cause of this flow  !

arrow stamping error was determined to be a vendor mistake. Dresser j also identified other type 7440W valves supplied to Plant Vogtle.

These were evaluated for Unit 2 as part of the broadness review  :

discussed later.

The root cause for three of the other valves being installed backwards was detemined to be incorrect or missing flow directions shown on i the isometric drawings. This was attributed to either an incorrect j interpretation of system flow from the P&ID onto the isometric, or i branch and miniflow lines on the isometric which did not have a flow l arrow associated with them, i i

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The root cause for the three Valcor valves being installed backwards was determined to be less than obvious flow direction indication on the valve and installers apparently unfamiliar with the flow indication given. The Valcor valves were stamped with "IN" on one end of the valve, but not with a flow arrow on the valve body as is normal practice for most other valves. It is postulated that the installers were not familiar with this type marking, did not see the inlet indication on the valves, and installed them in the same manner as globe valves (with flow under the seat). However, the valves should have been installed with flow over the seat.

Broadness Review: Tr.e Unit 2 Dresser type 7440W check valves were evaluated to detennine if the flow arrow had been stamped in the wrong direction. This evaluation involved either flow verifying the check valves or visually veri fying that the internals were installed for flow ir the same direction as the flow arrow. This review concluded that of the 59 Dresser type 7440W valves identified on Unit 2. only the three valves identified originally had the flow arrow stamped in the wrong direction.

A review was also conducted to detennine if any other safety related valves were installed opposite to the direction of system flow due to incorrect or missing flow directions on the isometric drawings.

The review consisted of:

1.0 Elimination of the following valves from further review.

1.1 Gate, ball, plug valves - Installation of these valves in either direction will not impact the flow or performance of the valve.

1.2 Check valves - Installation of check valves in the opposite direction will be detected during the system testing.

1.3 Relief valves -

Due to the configuration of relief valves, installation is not physically possible in the reversed direction.

1.4 Vendor preassemblies which include valves -

The isometric drawings are not used for installation of preassembled skids, panels, or equipment.

1.5 Vent and drain valves - The P&ID's and isometric drawings do not show process line flow direction for vent or drain valves.

The constructor installs these valves with the direction of flow away from the header.

2.0 Test connection valves - These valves were reviewed and accepted on a case-by-case basis.

3.0 Identification on the P&ID's of the remaining safety-related valves not eliminated above.

4.0 Comparison of the system and valve flow direction on the P&ID's and the installation isometric drawings for these safety-related valves.

5.0 Walkdowns to verify the actual installed conditions if the system or valve flow directions shown on the isometric drawings were missing, unclear or did not agree with the P&ID's.

6.0 Evaluation of engineering data to determine acceptability of the installed condition for the valves which were found to be installed backwards. The suppliers of valves found to be installed opposite to the direction of ficw were also contacted for information relating to the capability of these valves to perform their intended function for the life of the plant.

The results of this review concluded that a total of 29 valves were installed opposite to the direction of flow, and one valve was installed correctly, but the flow direction shown on the isometric was incorrect. The engineering evaluation of these valves concluded that 12 valves are technically acceptable as is, but the remaining 17 valves are required to be reworked and installed with the proper direction of flow.

All of the Unit 2 Valcor solenoid valves were inspected to confirm that they were installed consistent with the P&!D's. Of the Valcor solenoid valves identified on Unit 2, no others besides the three discussed above were found to be installed opposite to the direction of flow shown on the Pa!D's.

Analysis of Safety Implication: The three Dresser check valves with the incorrect flow arrow were installed in the nitrogen supply lines to steam generators #1, 2, and 3. During plant operation, the nitrogen supply lines are isolated from the steam generators by two normally closed manual globe valves downstream of the check valves. When the steam generators are not in service, the globe vsives are opened to provide nitrogen blanketing to prevent the ingress of oxygen while the steam gene . ators are in wet layup conditions. This is to protect the internals of the steam generators from corrosive attack. Thus the affected check valves would not have had an impact on plant safety during nomal operation or accident conditions. This situation is not considered reportable under 10CFR50.55(e) or 10CFR21.

Of the 29 valves installed opposite to the direction of flow due to incorrect or missing flow arrows on the isometric drawings, one has a potential for impact on plant safety. Valve 2HY-190A f a the train A Chemical and Volume Control System (CVCS) centrifugal charging pump discharge flow control valve for safety grade cold shutdown.

This solenoid-operated globe valve provides flow control of borated water from the centrifugal charging pump to the reactor coolant system during boration to cold shutdown concentration. It also controls makeup for primary system contraction due to cooling while the safety grade cold shutdown is performed. When installed backwards, valve 2HV-190A may not be capable of regulating the charging flow as required for safety grade cold shutdown. Assuming the loss of train B, this could potentially impact the capability to prevent or mitigate consequences of accidents.  ;

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The three Valcor solenoid-operated valves identified to have been installed backwards, also have a potential impact on plant safety.

Valves 2HV-10951, 10952, and 10953 are 3/4 inch Valcor solenoid-operated globe type isolation valves for the samole lines from the safety injection system accumulators. These valves are opened from the main control room so that samples may be taken from the accumulators for checking the boric acid concentration. They are located inside containment and also serve as containment isolation valves. Each sample line goes through containment to level B of the Auxiliary Building where a locked closed valve serves as the l

other isolation valve. These globe valves fail closed on loss of power. The valve closure is achieved by a spring with the fluid t pressure assisting for a tight seal. The reversed installation may I result in valve seat leakage. This potential valve seat leakage l combined with a single failure of the other isolation valve would

( result in a small but unisolable leak into the Auxiliary Building.

l Georgia Power Company is conservatively considering the four globe valves a substantial safety hazard as defined by 10CFR21 and a significant deficiency as defined by 10CFR50.55(e) since the ability of the containment to perform its function could potentially be compromised and the capability to prevent or mitigate the consequences of accidents could potentially be impacted.

I Evaluation of a Quality Assurance Program Breakdown: The three Dresser l check valves which had an incorrect flow arrow stamped on the valve l body were found to have been from the same production order. All i other Dresser valves of the same type on Unit 2 were reviewed. No l additional valves were identified with incorrect stamping. The

! incorrect stamping was isolated to one production order and is not l considered a significant breakdown in the Dresser Industries QA program f or Vogtle.

i l The root cause for the 29 valves being installed incorrectly has l been attributed to incorrect or missing flow directions shown on l the isometric drawings. Eleven valves were installed wrong due to

! incorrect flow directions on the isometric drawings. Seventeen valves l were installed opposite to the system flow direction in situations where no flow direction was shown on either the isometric or the continuation isometric d rawing. Field engineering, craft and QC made mistakes interpreting inadequate information on some drawings as to flow direction for the valves. Considering the total valve t population of approximately 3500, we conclude that there was not I a significant breakdown of the Project Quality Assurance Program.

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Three Valcor solenoid valves were found to be installed backwards due to craf t error in determining the flow direction for thi.tse valves.

Yalcor valves are marked to indicate the inlet side of the valve instead of flow direction arrows stamped on the valve body. Three Yalcor valves were installed backwards, all other Valcor valves were found acceptable. This is not considered to be a significant breakdown of the Project Qaality Assurance Program.

Conclusion:

It has been concluded that installation of the four globe valves discussed above opposite to the direction of flow could potentially have adversely affected the safety of operations.

Therefore, this condition is considered to be reportable under the requirements 10CFR50.55(e) and 10CFR21. Based on guidance in NUREG-0302, Revision 1, concerning duplicate reporting of an event, Georgia Power Company is reporting this condition per the criteria of 10CFR50.55(e).

Corrective Action: The three Dresser Industries one-inch check valves have been reworked so that the flow arrow and valve internals are consistent with the system flow.

The seventeen valves which were installed backwards due to the isometric drawings and were not acceptable, have also been reworked so they are installed with the system flow. The isometric drawings associated with these valves were revised to clearly reflect the correct flow direction.

The three Valcor solenoid valves which were installed backwards have also been reworked so that they are now installed correctly.

Those invol"ed with the incorrect installations will be advised of these conditions and instructed on how to prevent recurrence. This item is being tracked by MTS No. EA! B-5115 and is scheduled to be completed 10/30/88