RBG-45097, Requests Approval of Proposed Alternative to Second Interval Inservice Testing Program,Allowing One Time Extension of Test Interval for 20% of Full Set Main Steam Line Safety Relief Valves

Requests Approval of Proposed Alternative to Second Interval Inservice Testing Program,Allowing One Time Extension of Test Interval for 20% of Full Set Main Steam Line Safety Relief Valves

ML20211K657
Person / Time
Site:	River Bend
Issue date:	08/31/1999
From:	King R ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
RBF1-99-0242, RBG-45097, NUDOCS 9909080042
Download: ML20211K657 (10)

Text

p=

_-j Entirgy oporttions, Inc.

[. - River Bend Station 5485 U.S. Highway 61

-.1 ' ! "v~~) P. O. Box 220 y St. Francisville. LA 70775 Tel 225 336 6225 Fax 225 635 5068 Rick J. King Director Nuclear Safety Assurance August 31,' 1999 U. S. Nuclear Regulatory Commission -

- ATfN: Document Control Desk ,

. Washington, DC 20555

)

Subject:

River Bend Station Docket No. 50-458 License No. NPF-47 Second Interval Inservice Testing Program Request for Approval of Alternative  !

File No.: G9.5, G1.51 RBG-45097  !

RBF1-99-0242 I

Ladies and Gentlemen:

In accordance with the provisions of 10 CFR 50.55a(a)(3)(ii), approval of an attemative to the River Bend Station (RBS) second interval inservice testing program is requested. The proposed alternative, if approved, would allow a one-time extension of the test interval for 20% of the full set of main steam line safety relief valves. Operating Cycle 9 has been shortened from the normal eighteen months to approximately nine months. Accordingly, we propose to delay the set i pressure testing to no later than Refueling Outage 10 for the reasons described in the enclosed Valve Relief Request VRR-003. The RBS second interval inservice testing program was submitted in EOl's letter of December 2,1997 (RBG-44328/RBF1-97-0453). The applicable requirements and justification for the alternative are described in the relief request.

9909090042 990831 PDR ADOCK 05000458 P- PDR

1 Second Interval Inservice Testing Program Request for Approval of Alternative -

August 31,1999 RBG-45097 RBF1-99-0242 -

Page 2 of 2 Currently, Refueling Outage 9 is scheduled to begin on March 4,2000. To ensure that sufficient time remains in the event NRC disapproves the requested alternative, we request that the NRC's response be received no later than November 30,1999. ' At that time, if approval has not been received, plans to perform the set pressure testing must be finalized.

We have determined that there are no commitments in this letter. If NRC approves the alternative, the testing delineated in the relief request will be performed as described. If you have.any ques: ions, contact Patricia Campbell at 225-381-4615.

Sincerely, t /$

RJK/PLC d

enclosure cc: (w/ enc.)

U. S. Nuclear Regulatory Commission 1 Region IV

' 611 Ryan Plaza Drive, Suite 400 f

1 Arlington,TX 76011 NRC Resident Inspector P. O. Box 1050 St.Francisville,LA 70775  ;

i Mr. Robert J. Fretz U. S. Nuclear Regulatory Commission  ;

M/S 04-D-03 i Washington, DC 20555 i.

I River Bend inservice Testing Plan for INmps and Valves Interval 2, Revision 0 REQUEST FOR RELIEF VRR-003  ;

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I COMPONENT ID )

Main Steam Line Pressure Relief Valves:

B21-RVF041A B21-RVF041B B21-RVF041C B21-RVF041D B21-RVF041F B21-RVF041G B21-RVF041L B21-RVF047A B21-RVF047B B21-RVF047C B21-RVF047D B21-RVF047F B21-RVF051B B21-RVF051C B21-RVF051D B21-RVF051G l

CODE CLASS ASME Code Class 1 l CATEGORY ASME Code Category BC TEST REQUIREMENT:

ASME/ ANSI OMa-1988, Part 10, Paragraph 4.3.1, requires that safety and relief valves shall meet the inservice test requirements of Part 1. ASMF/ ANSI OM-1987, Part 1, Paragraph 1.3.3(b), requires that all valves of each type and manufacture shall be tested within each subsequent 5-year period, with a minimum of 20% of the valves tested within any 24 months.

This 20% shall be previously untested valves, if they exist.

River Bend Inservice Testing Plan for Pumps and Valves Interval 2, Revision 0 REQUEST FOR RELIEF VRR-003 ASME/ ANSI OM-1987, Part 1, Paragraph 3.3.1.1, requires the following:

(a) visual examination; (b) seat tightness determination; (c) set pressure determination; (d) determination of compliance with the owner's seat tightness criteria; (e) determination of electrical characteristics and pressure integrity of solenoid valves (s);

(f) determination of pressure integrity and stroke capability of air actuator; (g) determination of operation and electrical characteristics of position indicators; (h) determination of operation and electrical characteristics of bellows alarm switch;* and (i) determination of actuating pressure of auxiliary actuating devise sensing element, where applicable, and electrical continuity.

• RBS valves do not contain Bellow Alarm Switches; therefore,"h"is not applicable.

ALTERNATE TESTING:

A one-time alternative testing schedule would apply for operating Cycles 9 and 10. Due to a modified core design, Cycle 9 is scheduled to be a nine-month cycle. Cycle 10 is scheduled to be an eighteen-month cycle (RBS normally operates on an eighteen-month cycle). The plant  ;

operating time would be approximately 27 months, with the calendar time being approximately 30 months. This is an operating period of approximately three months, or 12.5%, longer than the 24 months period specified in OM Part 1. For each of the Main Steam Line Pressure Relief Valves listed above, the following tests listed in OM Part 1, Paragraph 3.3.1.1, would be performed during both Refueling Outage 9 and Refueling Outage 10:

(a) visual examination; (e) determination of electrical characteristics and pressure integrity of solenoid valves (s);

(f)(partial) stroke capability of air actuator; (g) determination of operation and electrical characteristics of position indicators, and (i) determination of actuating pressure of auxiliary actuating devise sensing element, where applicable, and electrical continuity.

l

River Bend Inservice Testing Plan for Pumps and Valves Interval 2, Revision 0 REQUEST FOR RELIEF VRR-003 For the Main Steam Line Pressure Relief Valves listed above, no later than Refueling Outage 10 (currently scheduled for September 2001), a minimum of 20% of the valves will be tested for the following tests listed in OM Part 1, Paragraph 3.3.1.1:

(b) seat tightness determination; l (c) set pressure determination;  !

(d) determination of compliance with the owner's seat tightness criteria; and l

(f) (partial) determination of pressure integrity. i BASIS:

River Bend has sixteen Crosby 8XRX10 main steam Safety Relief Valves (SRVs). The SRVs are the balanced type, spring-loaded, safety valves provided with an ate.~ ei:ny power-actuated device, which allows opening of the valve even when the pressure is less than the safety-set pressure of the valve.

In the past, undesirable performance of safety relief valves installed in operating Boiling Water Reactors (BWRs) was associated principally with multiple-stage pilot operated SRVs. The newer, power-operated safety valves, such as those installed in the RBS main steam lines, employ significantly fewer moving parts wetted by the steam, and are, therefore, considered an improvement over the multiple-stage pilot operated SRVs used in the industry.

The safety-related functions of the SRVs are as follows:

(1) to open under the spring set pressure (safety mode of operation) when the system static inlet pressure is at or exceeds the setpoint setting within the SRV setpoint tolerance; and (2) to open and remain open as actuated using the electro-pneumatic actuator that is installed on the valve (relief mode of operation).

These modes of operation satisfy the ASME Code overpressure protection requirements and the Automatic Depressurization System (ADS) requirements of the plant.

Safety Mode:

RBS Technical Specification 3.4.4 requires that five SRVs be operable in the Safety Mode, and an additional four SRVs (other than the five SRVs that satisfy the safety runction) must be operable in the Relief Mode. These requirements are only applicable tcane capability of the l

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River Bend Inservice Testing Plan for Purnps and Valves

, . Interval 2, Revision 0 REQUEST FOR RELIEF VRR-003 SRVs to mechanically open to relieve excess pressure. Analysis results show that with a minimum of five SRVs in the safety mode and four SRVs in the relief mode operable, the ASME Code design limit for the reactor coolant system of 1375 psig is not exceeded.

For overpressure SRV operation (self-actuated or spring lifl mode), the spring load establishes the safety valve opening set point pressure. The safety function of the SRV is a backup to the relief mode, as all relief mode settings are below the safety mode set points.

ReliefMode:

The relief mode of operation is initiated when an electrical signal is received at any one of the solenoid valves located on the pneumatic actuator assembly. The solenoid valve (s) opens allowing pressurized air to enter the lower side of the pneumatic cylinder's piston, pushing the piston and rod upwards. This action pulls the lifting nut upward via the lever arm mechanism and opens the valve, allowing inlet steam to discharge through the SRV even if the inlet pressure is equal to zero. All sixteen SRVs are dc::igned to be operated in this mode.

To meet the requirements of OM-1987, Part 1, Paragraph 3.3.1.1, Items (b), (c), (d), and (f)

(partial -- determination of pressure integrity), the selected SRVs must be removed and bench tested. Paragraph 3.3.1.1, Items (a), (e), (f) (partial -- stroke capability of air actuator); (g), and (i), where applicable, and with electrical continuity, can be performed with the valve installed in the system and without causing unnecessary challenges to safety systems.

In the past RBS has satisfied testing requirements by installing a full complement of pre-tested valves in place of valves that had been in service. The removed valves are set pressure tested within 12 months of removal from the system in accordance with OM-1987, Part 1, Paragraph 1.3.3.1 (c)(2). The last full replacement was made during Refueling Outage 8, which ended in July 1999.

Refueling Outage 9 is scheduled for March 2000, which will be approximately eight to nine months from the end of Refueling Outage 8. RF10 is currently scheduled for September 2001, which would be approximately 27 months from the end of Refueling Outage 8. If OM-1987, Part 1, Paragraph 3.3.1.1 (b), (c), (d), and partial (f) are not performed during Refueling Outage 9 on four SRVs (16 x 20% = 3.2), the Code requirement to test 20% of the valves within any l

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River Bend inservice Testing Plan for Pumps and Valves l

Interval 2, Revision 0 REQUEST FOR RELIEF VRR-003 24-month period would be exceeded by approximately 3 months (reference OM Part 1, Paragraph 1.3.3(b)).

' Additionally, RBS has submitted a request to the NRC to approve a Power Uprate of approximately 5% (reference letter dated July 30,1999). As part of the implementation of the full uprated power, the SRVs must be modified with set point adjustments. Pending NRC approval, the implementation of the full power uprate for RBS will be prior to startup from Refueling Outage 10. As part of the request for power uprate, a change in the set points for the SRVs and a change in the tolerance for the set points are proposed. A set pressure tolerance of

+/- 3%, with valves reset within +/- 1%, was proposed. The current tolerance is +0%, -2%.

The alternative testing will extend the "20% of the valves within any 24-month period" to "20%

of the valves within any 30 months" for Cycles 9 and 10 only. No later than during Refueling Outage 10, the OM Part I requirement to set point test 20% of the valves will be met (specific items of Paragraph 3.3.1.1 are listed above).

The only way to meet all of the testing requirements would be to remove and test SRVs that were installed for only eight to nine months, or approximately one half of a normal operating cycle. ,

-Removing SRVs and shipping them to a test facility is difficult and costly in terms, not only of the resources involved in removing the valves, shipping them, reinstalling the valves or installing L pre-tested ' replacements, but the possible extension to a planned short refueling outage after a j short operating cycle. This is an unnecessary burden in light of the history of the set pressure

- testing of these valves.

The attached table gives the results of the set pressure testing for the SRVs installed during Cycles 5,6, and 7 (Cycle 8 SRVs have not yet been tested). As shown, of the 48 tests, only four of the set points were higher that the accep;ance criteria, and only one of these four was higher than 1% above the specified set point.. While several set points were found below the -2%

l acceptance criteria, the safety significance oflifting at a lower pressure is low because the primary function of the valves is to protect the reactor coolant system from overpressure. The data support the premise that the longer period of time (approximately three months) would not tend to cause the set points to drift to a value significantly above the acceptance criteria.

Additionally, analysis has been completed that supports an increase in the set point tolerance of the valves as part of the power uprate project (see discussion above). As such, even a drift up to 3% above the set point would have no impact on public health and safety.

River Bend inservice Testing Plan for Pumps and Valves interval 2, Revision 0 REQUEST FOR RELIEF VRR-003 i

With all of this supporting basis, compliance with the current OM Part I schedule of 24 months for set pressure testing at least'20% of the currently installed SRVs, versus performing the testing I after approximately 27 months of operation, would impose an unecessary hardship and burden I without a compensating increase in the level of quality and safety. The alternate testing proposed above will provide assurance that public health and safety are not compromised. Accordingly, the alternate testing proposed above is requested pursuant to 10 CFR 50.55a(a)(3)(ii). I

REFERENCES:

1. ASME Section XI,1989 Edition (no addenda) 2 ASME/ ANSI Oma-1998, Part 10

3. ASME/ ANSI OM-1987, Part 1

4. RBS USAR Section 5.2, Integrity of Reactor Coolant Pressure Boundary

5. Crosby Instruction Manual for HB-65-DF, Safety Relief Valve [ Pub. I-l1070]

6. RBS Tech. Spec. 3.4.4, Safety / Relief Valves (S/RVs)

7. RBS TRM, TR3.3.6.4, Relief and Low-Low Set (LLS) Instrumentation

8. RBS Letter RBG-45077 (RBF1-99-0215)," License Amendment Request 99-15, Changes to Technical Specifications for Power Uprate of River Bend Station," dated July 30,1999.

. APPROVAL:

Pending NRC Approval l

ATTACHMENT: 1 Safety Relief Valve Testing History i

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River Bend Inservice Testing Plan for Pumps and Valves

, , Interval 2, Revision 0 I REQUEST FOR RELIEF VRR-003 Attachment Safety Relief Valve Testing History Valve No Serial No Date Name Plate SP As Rec SP Pass / Fall SP

.B21-RVF041_LJN_63800.-00-0112j 4/26/951 1165[ 1136, Failed (-2.5%) l 4/20/95j_ f B21 RVF051B[N83800-00-0123 ' 11901 1194 Failed (+0.34%)'

B21- l N63800-00-0121 4/24/95 1190 1168; Pass RVF051 G ,_ .{ _ _ _ _ _ . j ___g B21-RVF051C!N63800-00-0120 i _ _ . _ _ _4/19/95 1190_____ 1173; Pass B21- :N63800-00-0111 i 4/25/95 1165 1146 Pass RVF041G_ _ .{ _ _ . _ _ l B21-RVF041C;N63800-00-0109 ! ~

4/22/95 1165 1151 Pass B23!R VF0iiffN638d6 0 -0I07 l 4/27/s5 1165 1175fFailed (+6~5d*5)"

B i-RVFf45D N63800-00-0106 ' 4/25/95 1165 1152 Pass

'B25RVFOI7EN535Dd! ~~

0 f05U i 4/5dl95 1180 1158 Pass

'B25R9FOI7Ci A63800 00-0D98Y 4/22 95- iib 0T 1149$Faifed~ (!

^

2 ~63 5)~

B2I~R9F547{N55800}00[6097[ 4/26I95 . _1il80'j 1155iFaiIkd 62 37Q B21-RVF047F;N63800-00-0095 l _4/26/95 1180l 1153IFailed ( 2.3%)

B 1 1175lPass

~ 5IXVF657 DIN 63ls00[0_l0 0 81] 1186[

B21-RVF051D N63800-00_-004_7j 7/25 4/26/95 95(( 119_0j 1182! Pass 821-RVF041AI_N63800-00-0040 l 4/23/95 1165I 1146 1I551[ Pass

~

'B21T ~ R 9F045F]N538D600%059 ~

l 4/25/95- 1165l Pass B25RVF64fAjN55500-02{6033j 4/21/97 1165{ 1184!Failedj+.1.63%).

B21-RVF041B:N63800-02-0034 : 5/7/97 1165 1154lPass l

.B21-RVF041D B21 -RVF 'N63800-02-0036 04_1_C_y6_3800-02-0_03_5j[ 4/2_8/97 _ 116_5 _1139]Failedlf.~53Q g

5/8/97 11651 1175 Failed (+0.86%),

B21-RVF041F lN63800-02-0037 , 5/2/97 11_60jPass _ ._. _

1165[ _

B21- ;N63800-02-0038 l 4/25/97 1125l Failed (-3.43%)

RVF041G 1165l l  !  : I 5fi! VF041L R [N63800-02-0110 i 5/7/97 1165I 1144IPass ~

B2T-~RVF64fAlN6380d~-Of~0041N ~

4/23I97 iib 0f 1145iFaii~e~d (-3T53"f)'

~

l B2T-RVF6I7FA658d6%2 0dds-[

~

4/24I97" ~iT8d" 11A5IFaliid (-312*Ai~

B2T-RVF047CiN63806!02 ~-~0043 i 4/25/97 1186~~~1552iFailed (-2!37) ~~~ l IB25~RI/F0d7DlN63800T~! O2 00441 4/5DI97 ~~

118d 114f[ Failed (-3.22%)_ '

1 4/29/97" 1 550I T132l Failed (-4.0%)

fBiiMVF647FTN63800-02

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0

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60iST 4/2'6 97 11_90{ _fi49]Faifed]~5~44(

I'B25-R'VF 5}B]6380D! i[ 0d61 B21-RVF051C : N63800-02-0115 4/30/97 1190l 1179jPass B25-h9i-D5ID'Nd356~0  ! 62-dii7E

~ 4T22797 1190j__1161[ Failed (-2744%j] l B21- ;N63800-02-0118 ; 5/2/97 1190j 1167l Pass _ _.

RVF051G  ! ~~

Bli~RVF64TF7N55Ed IDE~ 639 I 8/26/98; 1165~ iiS3fPass -

B2T'RVF04i lN63860  ! 06 046'I~~8I2sI98[ ii65" tis 6IP' ass" ~ ~l i B25RVFD5iDj@pd}60{DUA7 1 s/25798} 1190~ 11771 Pass I

Safety Relief Valve Testing History Valve No Serial No Date Name Plate SP As Roc SP Pass / Fall SP

,821-RVF047DjN63800-0_0-008Q 8/29/98 1180, 11_53}Faile_dj-2.29%)_

.B21-RVF047FjN63800-00-0095j 8/21/98 1180 _1_155! Failed (-2.1% )_

B21-RVF047A 8/24/98 1180 1157 Pass

'Bli-RVF I7C)[N63800-00-0097 iS6380d ~60 Od98"i

~

8 28I98

~~

iTs0l 1iS4 Pais B21-RVF047 BIN 538Dd~ 0 did'0 8T25798 1180} 1152 Failed (-2.4% )

Bj((R FM{D]N638p@@j 6 8/59I98 1165} ii37 Failed (~-'2T4%T~

B21-RVF041 bin 63800-00-0107 i 8/18/98 11651 1125 Failed (-3.4% ) ~

B21-RVF041CIN63800-00-0109 8/31/98 1165 1154 Pass ~

821- lN63800-00-0111 8/2dI58 1155 114TPass 2- 8g9798 1165 11403ailid}(}-2[i{

.B21-RVF _ 55356d% doi [2]I N_63800-00-0120 ! 8/27/98 1190 1141 . Failed (-4.1%_ )_.

B21- lN63800-00-0121 i 8/19/98 1190 1183 Passed RVF051G  ! I B51-R9FdisfB]N63800-00-0123 I 8/27/98 1190' 11601 Failedj-2.5%_)_. ]

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