ML20077F058
| ML20077F058 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 11/03/1994 |
| From: | Keaten R GENERAL PUBLIC UTILITIES CORP. |
| To: | Martin T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| 5000-94-0045, 5000-94-45, C311-94-2151, NUDOCS 9412130256 | |
| Download: ML20077F058 (14) | |
Text
,.
GPU Nuclear Corporation
_6 Nuclear
= = zos.
201-316-7000 TEi EX 136-482 Wnters Deect Dial Number.
(201) 316-7112 November 3.-1994 l
5000-94-0045 i
C311-94-2151
(
Mr. Thomas T. Martin l
Administrator, Region i U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406
Subject:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Docket No. 50-289 Response to Inspection Report 94-12 l
TMI-l Motor Operated Valve Inspection i
Dear Sir:
The NRC in the letter transmitting the TMI Unit 1 Motor Operated Valve Inspection Report 94-12 dated August 30, 1994, requested GPU Nuclear to submit the information described in Generic Letter (GL) 89-10 Supplement 6.
GPU l
Nuclear previously reported to the NRC in letter C311-94-2086 dated June 29, l
1994, the status of the TMI-l Generic Letter Program.
In addition, GPU Nuclear met with the NRC at Region I offices on October 20, 1994, to further discuss the NRC concerns regarding the TMI-l MOV Program.
GL 89-10 Supplement 6 requested a response from licensees who intend to extend their current schedule commitment.
GPU Nuclear is not requesting an extension but is submitting this response as requested in Inspection Report 94-12.
The 1
GPU Nuclear initial response to GL 89-10 for TMI stated that GPU Nuclear would implement the schedule for completing the recommendations within three refueling outages for TMI-l with the exception of not including 8R.
This co o' results in completion by the end of the TMI-l llR outage currently scheduled oS@
for September / October 1995.
-o
reduced due to revised design basis for two valves previously in the program.
M Static testing is complete on all 79 valves in the GL 89-10 program.
Where f
No feasible, in-situ dynamic testing has been performed on representative valves.
8@ %
M Evaluation of the dynamic test results is in progress in conjunction with i
review of industry data on similar valves.
I M
e Corrective action has been taken on several valves including; valve
.. 4 replacement, spring pack replacements, motor replacement, and EIM motor f
operators replacement on butterfly valves with Limitorque operators.
/ 4
4 r
Document Control Desk C311-94-2151 Page 2 Validation of the calculation assumptions is discussed in the attachments.
Voltage calculations have been completed including consideration of thermal effects. Design verification of these calculations is in progress.
Reverification of adequate motor torque is required after selection of the final valve factor.
After selecting valve factors based on test data or best available information, all valves received preliminary review to assure they are functional with their present setpoints.
Based on preliminary reviews, all valves are functional as indicated by available valve factor or torque margin. Some valves do not have desired margin to account for all uncertainties. The calculations reflecting revised assumptions, update of the allowable setpoints and identification of corrective actions will be completed by January 1, 1995.
If corrective actions are required, an operability determination will be completed.
Any additional corrective actions required as a result of updating the calculations will be scheduled to be completed by the end of the TMI IIR outage.
Trending, sampling and preventative maintenance program changes will be ma.de to support the TMI GL 89-10 M0V program.
The NRC will be notified by letter when the TMI GL 89-10 M0V Program items are completed.
If you have any further questions please contact Dennis Hassler, Licensing Engineer, at 717 4 48-8833.
Sincerely, h dd R. W. Keaten Director, Technical Functions DVH/mkk cc:\\. G. Evans - TMI Senior Resident inspector M
R. W. Hernan - Senior Project Manager E. M. Kelly - Chief, Systems Section, Division of Reactor Safety
C311 94-2151 ATTACHMENTS
SUMMARY
Attachment i Valves With Valve Factors Confirmed By In-Situ Dynamic Test i
Valves Justified By Grouping (TMI or Industry Data)
Valves Justified Without Data (TMI or Industry)
Explanation of Terms Valve Grouping Criteria l
I i
i i
i i
i
1 ATTACHMENT 1 l-VALVES WITH VALVE FACTORS CONFIRMED BY IN-SITU DYNAMIC TEST The 38 valves on Table I have been dp tested to at least 60% of design dp (except two valves, RR-V-1A and B). The dp test confirmed that the valves are functional at the present torque switch setting.
Valve factors will be determined from these tests to ensure thrust windows are correct for future testing.
Back calculated valve factors will be incorporated into the switch settings as follows:
l.
l Determine valve factor and, if required, recalculate thrust requirement a.
for the new valve factor, l
b.
Apply margins for Torque Switch (TS) repeatability,-Load Sensitive Behavior (LSB), Time Related Stem friction degradation, and test i
equipment accuracy.
(The initial setting programmatically used a 25%
margin for those factors).
l c.
Determine allowable maximum thrust based on weak link limits.
d.
Determine the new thrust band based on the revised thrust calculation and specific margins.
e.
Verify that the as left thrust at TS trip is in the allowable thrust band.
f.
Verify motor torque at degraded grid voltage is adequate.
These actions will be complete ty January 1,1995.
1 Validation of assumptions:
Valve Factor: To the extent practical valve factor was determined from dynamic tests.
Stem Coefficient of Friction (C0F): The stem C0F used in the calculation was 0.2.
The C0F on some valves appear to be higher than 0.2, particularly on rotating rising stem valves. The data taken in some cases does not provide a direct and accurate measurement of C0F.
C0F was estimated based on generic i
spring pack curves; therefore, a C0F of 0.2 is considered to be a reasonable assumption.
The valves have been set up based on the actual C0F to provide the required thrust within the original allowable Torque Switch Setting band. A sampling program has been established to further validate 0.2 as an appropriate value for C0F and to assess stem lubrication degradation over the maintenance interval.
Load Sensitive Behavior (LSB):
Values for LSB were determined from these valves that were dynamically tested and will be applied to the remaining valves.
LSB will be factored into the torque switch setting in two parts.
The calculated required thrust will be increased using a multiplier.
The second part of the LSB correction will be included as a random variable and will be combined with the other random effects.
Stem Lubrication Degradation: A correction will be applied to account for potential increase in friction over the lubrication interval. The sample program will provide data to assess whether the correction is appropriate.
TABLE 1 - VALVES COMPLETE BY DIFFERENTIAL PRESSURE TEST (FULL OR EXTRAPOLATED)
VALVE i TYPE SIZE j POSITION
! DESIGN DESIGN DESIGN' AVAILABLE AVAILABLE RISK TEST VALVE TAG l
!NORMAli SAFETY l BASIS BASIS BASIS VALVE VALVE FACTOR DP FACTOR-NO j
l ACTION l OPEN DP DP FLOW FACTOR FACTOR (4)
O/C i
(5)
CLOSE (GPM)
OPEN CLOSED (6) l l
(1) (3)
_ (2) (3)
,_.33. NO DP EFF BS-V-2B GATE {
4' CLOSEDjOPEN 33 33 1500 12.471 3.023 L_OW_. _
43 NO DP EFF BS-V--3A _ {1 GATE _ ]l_ 12 OPEN fCLOSE.;
_ 18 i
1500 1.171 LOW 18 iS00 _
_7.226 2.870 l_OW__
_ 116 0.51/0.53
_ 43_ [
10 OPEN_ jOPEN_j 43 CO _V_--14Bj GATE _ 12 J CLOSED _ j O_ PEN _
1.083
.162.611. MEDIUM. _ _ _ _
164
.50 l
_39, ___ 1 L _ 3300
_ _ 3.643
. _ 1.034fHIGH 37 N_O DP EFF DH-V-3 _ j _ GATE j _
DH-V-6A GATE 14 CLOSED jO/C
_ _37,
_.37
. 4700 2.671 0.722. H_lG_H_ _
._.__ 37] NO DP EFF 4700
_ _2.778 Di-i-V-6B GA(
14l CLOSED jO/C 37i 37 D H_-- V-78
._ GATE,
14 CLOSED lOPEN j
218!.
218 954_
1.656 0.626, HIGH _
212
.45/.36 IC-V-2 GATE !
6 OPEN lCLOSE ~
144 144 40 1.025 1.094.. LOW
_[
142 0.25- 0.28 MS-V- 2A_
_ GATE 12 OPEN_ {CLOSE 1
50.6 (9).
149.692 5.150 LOW M S -- V-- 2.B.
GATE 12 OPEN, jC_ LOSE 1
50.6 (9)l 142.782_..
_. 5._601_LOW
_(7)
(8)
...(7).
(8)
RB-V-2A _
GATEj.
2;OPEN _]O/C 3118 3118l 105j 0.840 0.490 LOW _
2976.. 0.12 -0.20 MU-V-36 GATE _p 2 OPEN iO/C 3118 3118; 105j 0.856 0.3_6 LOW 5
GATE ;
8 OPEN
{CLOSE 61 61j 1700l 1.400 iM53 LO R
_ 2976, 0.22- 0.30 MU-V-37 61' O.28 61!
61 1700j 0.628 0.684 LOW
__ 61 0.26 RB-V-7 GATE i 8 OPEN_
jCLOSE RR--V-3 C GATE 12jOPEN
- OPEN, 53_
53 3200 1.455,.
_0.735 LOW
]82 ( ~0.20f 0.41 RR--V-3 A GATE 12 OPEN OPEN 531 53 32001 1 451 0.864 LOV[
_ 82 0.81/0.57_
RR-V-4A
. GATE
__12 CLOSED. _OP_EN _
124 124 3_200 0.628 0.594_. LOW __
_124 0.28/0.24
_124 0.36/0.36-_
RR-V-4D GATE 12, CLOSED OPEN
_ _124
_124 3200 0.628 0.490 LOW 12. CLOSED
.OPEN_
RR--V--4C_ _ _ I GATE 124 124 3200 0.638 0.528 LOW 124 0.30/0.32 2224 2224l 1
2.224 1.424 MEDIUM TO LOW CA-V-3 GLOBE 1l CLOSED O/C
~
2.093_ LO7 -
~'
2183 NO DP EFF CA-V-4A _
GLOBE 1 CLOSED' O/C 1050 1056[
1 3.444
~ i6 NO DP NFF 9
CA-V-13 GLOBE 0.5 CLOSED. O/C 2374 2374 1
_2.834_
1.604 LOW.,
2182 pO DP EFF CF-V 2A.
GLOBE L 1 CLOSED CLOSE 630 630 5
6.133 4.740 LOW 600 NO DP EFF CF-V-2B GLOBE 1 CLOSED CLOSE 630 630 5
5.544 5.506 LOW 600 NO DP EFF MU-V-16A GLOBE 2.5 CLOSED O/C 3118 3118 274 2.171 1.549 MEDIUM 2429 NO DP EFF NiU-W 16C GLOBE 2.5 CLOSED O/C 3118 3118 274 2.092 0.918. MEDIUM 2429 NO DP EFF FfC3Vf4 GLOBE
_ 1.5 CLOSED CLOSF 182 182 190 39.901 9.832 MEDIUM TO LOW 173 NO DP EFF RC-V-28 GLOBE 1 CLOSED OPEN 2450' 2450
' (10)
~7.045 2.296 'M$DiUM TO (.OW
' 2265' NO D'P EFF SUPP6DP
i TABLE 1 - VALVES COMPLETE BY DIFFERENTIAL PRESSURE TEST (FULL OR EXTRAPOLATED)
VALVE TYPE SIZE -
POSITION DESIGNj DESIGN DESIGN + REQUIRED AVAll.ABLE RISK TEST VALVE TAG NORMAL SAFETY BASIS BASIS BASIS TORQUE TORQUE FACTOR DP
' FACTOR NO ACTION DP DP FLOW FT-LBS FT-LBS (4)
.O/C.
(5)
OPEN CLOSE (GPM)
@TST
-(6)
(PSI)
(PSI) 4 DR-V--1 A '
B' FLY 20 CLOSED OPEN 53i 53 8000 583
~753~ I-ilGil~ ~
'49" DR--V-1 B _
B" FLY 20' CLOSED OPEN.
53 53 l8000 583
[541 'l-llGH] ~
~~
~49 54 NR-V-1A B' FLY 16 OPEN JOPEN 54 54 6000 388 488 MEDIUM- ~~'
~54
'~
~
585
~
~ '52i" iVf$DiDigi
^
NR--9-i B~
B'Fij
~ i6jOPsN OPnN ~
54
'54 6000~
~ 58 4
$biOW ~~
-' B'FL [i6 OPEN
~~~56%~ DIN
~' ~ { 754
'B' FLY DPNN ~
T54 !
54 ~ '600d 3
Nii1~9-i6' 30 CLOSED CLOSE 57 57 6000 1600 3215 I_
30 Nii1Vi4A NR 91hB
' B'FL ~ ~ ~30'6LdSED CLOsE 57'
~
'57i~~6000
'~
~i666'
'~~529I' LDW
~ ~ ~ ~ ~
~ ~ ~YO '
~ ~
Z
~
~~
~
FIR}9--i
~ B'l% '.
~ I6 ' Cl_D_ sed OP$N~
'131
~ 13i 69D0
[745 ]~
]0d5 i.O{ ~
I ~ 65 ]
16 CLOSED OPEN 131 131 6900 745 899 LOW
.63l RR-V-1B B' FLY
'iO CLOSED CLOS 8D l. 141i 14i 9600'
~?20
'284 LDih ~
'127i' RR-V-5~~
B'FL (1) - Calculated based on motor torque at undervoltage adjusted for thermal effects (2) - Calculated based on as-left closing thrust at torque switch trip (3) - Calculated values have not been adjusted for accuracy, LSB or other factors effecting margin (4) - This is the priority ranking as listed in the TMI Program Description (5) - O/C indicates that the valve has a dual safety function (6) - NO DP EFF indicates that the thrust signature did not show DP effects (7) - The DP was not directly measured but by calculation of system parameters it was above the design basis DP.
(8) - Since the actual test DP is unknown the valve factor O/C cannot be calculated. The test results were acceptable and the valve is considered functional.
(9) - 500 CU. FT./HR STEAM (10) - 9500 CU. FT./HR STEAM AND NON-CONENSIBLE GAS SUPP6DP
=
. ATTACHMENT 2 VALVES JUSTIFIED BY GROUPING (TMI or INDUSTRY DATA)
The 31 valves listed in Table 2 are valves that were not differential pressure tested but are similar to either TMI valves or industry valves that have been differential pressure tested.
The valve factor will be determined from TMI, EPRI, and industry data.
Available valve factors open and close have been calculated for the gate and globe (including stop check) valves.
The available valve factors will be the basis for the design basis capability assessment.
GATE VALVES Seven (7) of the 17 gate valves have an opening safety function.
Six (6) of the valves have an available valve factar open of 0.907 or higher.
The 0.907 is much higher than any open valve factors noted at IMI or expected from EPRI or industry data.
The available valve factor open for RR-V-4B is 0.639 which is similar to available valve factors for identical valves that have been differential pressure tested.
Twelve (12) of the 17 gate valves have a closing safety function.
Eight (8) of the valves have an available valve factor close of 0.733 or higher.
The 0.733 is much higher than any close valve factors noted at TMI or expected from EPRI or industry data. The other four (4) valves have available valve factors close ranging from 0.542 to 0.677.
These valve factors are above the valve factors for similar valves from EPRI or industry testing.
GLOBE VALVES All 12 of the globe valves have available valve factors both open and close of over 1.1.
All of the globe valves are in non-blowdown service and the appropriate area (guide or seat) has been used to determine the required thrust. A valve f actor of 1.1 is accepted for non-blowdown service globe valves.
BUTTERFLY VALVES The two (2) butterfly valves have an as-left torque at torque switch trip of at least 10% above the vendor recommended torque.
e TABLE 2 - VALVES JUSTIFIED WITH BEST AVAILABLE DATA VALVE
, TYPE SIZE j POSITION DES!GN i DESIGN DESl'3N AVAILABLE ' AVAILABLE RISK TAG l
! NORMAL ' SAFETY BASIS BASIS BASIS VALVE VALVE FACTOR-ACTION DP DP FLOW FACTOR FACTOR-(4)
NO l
OPEN CLOSED (5)
OPEN CLOSE (GPM) i l
[
(PSI)
(PSI)
(1) (3)
(2) (3)
BS-V-2A GATE i 4 CLOSED 10 PEN 33 33-1500 12.783 5.690 LOW BS-V-3B GATE !
10 OPEN
!OPEN 43' 43 1500 t.054 i.583 l LOW
~
CD V-14A GATE I 12,OPEN ICLOSE 18 18 1500
'1.122 1.749 i LOW CO-V-111 B GATE i 4' OPEN
!CLOSE j
26 26 0
_ 13.13d
[7.780 [69f/
~
CO-V-ill A GhTE. l
'4iOPEN
!CLOSE f
26 25' O
7.302. LOW 3.967 Dif-Vf7A' ~
GATE
' 'd ' CLOSED ~!OPEN 218 218f 954 1.695 0.525 HIGH EF-V-2A GATE 6iOPEN
)O/C 653 6531 550 0.907i 0.798 LOW.
EF-V-2B G TE 6 OPEN iO/C
}
653j 653l 55d
.910I 6,816 LOVV
~
2401 580!
3100
! 2.d29
'O.570 ME61UM TO LOW FW-V--92A GATE 6'OPEN
- CLOSE I
FW -V-928 GATS 6 OPEN CLOSE 240I 550!
310d 1.695 d.579IiONDIUh4 TO LOW
~
NS-9-- T GATE !
8 OPEN CLOSE
'80 80!
832
~~d.528' 6.577 i_dVV
~ ~ ~ ~
NS-Vf15
,G^TE[
5 OPEN CLOSE.
50 158 832 1'638' O.542 iOp
~
3 NS-V-35
. GATE j _
8 OPEN CLOSE 80 80; 832 1.214,
1.261 LOW i
CLOSE l
2367 2367 (6) 1.142 0.733. ! MEDIUM TO LOW RC -_V -- 2 _. _
GATE 2.5.OPEN OPEN_
53, 3200!
0.639
-0.528 LOW 1.093 LOW R R V-- 3 B_ _ _
_ G AT E 12 0.P E N.
53 3200; 1.469 7
7 7.
..T CLOSED CL6SE i
~ 124j
~ 163 30i
- 0.624 l 5.06f iiEDiuu 124 RR_-V-4B GATE 12: CLOSED OPEN 16si 1
SUPP6lD
.~.
TABLE 2 - VALVES JUSTIFIED WITH BEST AVAILABLE DATA POSITION DESIGN DESIGN DESIGN
. AVAILABLE AVAILABLE RISK VALVE i TYPE SIZE TAG NORMAL SAFETY BASIS BASIS BASIS VALVE VALVE FACTOR l
NO ACTION DP DP FLOW FACTOR FACTOR (4).
(5)
OPEN CLOSE (GPM)
OPEN CLOSED l
(PSI)
(PSI)
(1) (3). _. _(2) (3).
BS-V-1A GLOBE.
8. CLOSED
.O/C 270 270 1500 2.112 1.776 L.OW 2__
BS-V-1B GLOBE 8 CLOSED O/C 270 270
.1500 2.049 2.332 LOW _
C5_kQ$fB[ ' GLOBE
__[ CLOSED ' b/C.
]O5U
__1050 1 [ [3d52][ 2.21} [Op
~
p MU-V-2A GLOBEl' 2.5 OPEN CLOSE
{
2377 2377 70j 2.116 1.401 MEDIUM 5377
-2577
~ ~ 6 ~ ~2 05i ~
~ i.~55i Tj5diUMI
' ~ ~ ~
l OIO-VZ~2B '
GLd55 21 dPEN
'CLb5E 7
~
t MKphM G_ LOB 5. _ } 2.5 C'LdSED O/C ~
31i8
_3118
~ ~
[2}4 ~]
2.187~~ 'i @55 ' M5biU~Mi [][
~
@$ d25 G[dBE
~
~
t 3118 274 2.092 1.523. MEDIUM 2.5 CLOSED O/C 3118 MU-V-16D (( GLOBE [_[j[O' PEN [CLDSE
_1.i o fio 20 47.954 18.791 MEDIUM RC-V-3 GLOBE 2.5 OPEN O/C 120 WDG-V~13 G[ dE~
2 CLO5ED CLOSE
'55
~
120 190 45.618 8.496 MEDIUM TO LOW
~
55
'(V)
[id'.745 [~ ~ fM55 MNDIUE!. ~
~
i OPEN 35 35 824 24.366
-5.337 HIGH MU-V-14A STCHK 6 CLOSED '
OP EN. _.
35_
35_
. _24_
_ _24.754
' ~
' 5[65_5_.
HiG_l_i_
M_U._ Z -148 S_ T_ _C H K 6 ' CL._O55D 8
_.V_
_q_.
f REQUIRED AVAILABLE TORQUE TORQUE-FT-LBS FT-LBS
@TST t _.._
256 AH_ _ _ _ _..1B B' FLY j. _ 48 CLOSED C L_O S E.
1 25
,(8) 281 MED_ LUM AH-V-1C B' FLY l 48 CLOSED lCLOSE 1
25-(8) 256 296 MEDIUM (1) - Calculated based on motor torque at undervoltage adjusted for thermal effects (2) - Calculated based on as-left closing thrust at torque switch trip (3) - Calculated values have not been adjusted for accuracy, LSB or other factors effecting margin (4) - This is the priority ranking as listed in the TMI. Program Description (5) - O/C indicates that the valve has a dual safety function (6) - 1.11x10 ^ 5 lbs/hr steam (7) - 200 CU. FT./HR GAS (8) - 14,000 SCFM SUPP61D
^
ATTACHMENT 3 VALVES JUSTIFIED WITHOUT DATA i
(TMI or INDUSTRY)
The ten (10) valves listed in Table 3 are valves that were not differential pressure tested and for which EPRI or industry data has not been located to determine valve factors.
Available valve factors open and close have been calculated for the valves.
The available valve factors will be the basis for the design basis capability assessment.
GATE VALVES Six (6) of the 10 gate valves have an opening safety function. All of the valves have an available valve factor open of 1.858 or higher. The 1.858 is much higher than any open valve factors noted at TMI or expected from EPRI or industry data.
)
Eight (8) of the 10 gate valves have a closing safety function.
These valves have an available valve factor close of 0.649 or higher.
The 0.649 is much higher than any close valve factors noted at TMI or expected from EPRI or industry data.
4
TABLE 3 - VALVES WITH NO BEST AVAILABLE DATA VALVE TYPE SIZE POSITION DESIGN DESIGN DESIGN AVAILABLE AVAILABLE RISK TAG NORMAL SAFETY BASIS BASIS BASIS VALVE VALVE FACTOR f
NO ACTION DP DP FLOW FACTOR FACTOR (4)
OPEN CLOSE (GPM)
OPEN CLOSED (5)
(PSI)
(PSI)
(1) (3)
(2) (3) _ _
CF-V-1A GATE
_ 14 OPEN CLOSE_
(6) 633 100
_0 1.036
__ 6.625 LO_ _W _
CF-V-1B GATE.
__ _14 OPEN_._
CLOSE__ (6) 633 _ _100 __.0 _ _ 0.949 4.474. LOW i
DH-V-1 GATE 12 CLOSED OPEN 376 184 3300 1.858 1.366 MEDIUM GATE 12 CLOSED OPEN 376 184 3300 1.990 1.845 MEDIUM DH-V-2 ~~
G T5
- ~id Ci_D5E5 UIC" ~ ~ ~
~ 65'
~ 54
~ 556U
~
2.380 4.636 MEDIUM DNi9-4A 1
5 DH-V-4B GATE to CLOSED O/C 508 184 3300 2.281 ;
1.613 MEDIUM g ;9 g -t g g -
iA 0)~55~
O/5~~'
~~ ~55 ~ ~55 ~~~5505 ~~~ ~5350' 1.496 LOW DH-V-58 GATE 14 OPEN O/C 35 35 3300 2.230 0.998 LOW fQQ~_Gl'~5A 55T5~ ~ ~5U Uf)5N Di~d55~
~'100
~55U ~15605
~~
'5~554 1649 MEDIUM TO LOW
~
FW-V-58 GATE-20 OPEN CLOSE
- 100, 580 13000 2.699 0.894 MEDIUM TO LOW (1) - Calculated based on motor torque at undervoltage adjusted for thermal effects (2) - Calculated based on as-left closing thrust at torque switch trip (3) - Calculated values have not been adjusted for accuracy, LSB or other factors effecting margin (4) - This is the priority ranking as listed in the TMi Program Description (5) - O/C indicates that the valve has a dual safety function
]
(6) - This is an operational DP, the valve has no open safety function.
SUPP6NID
~ ATTACHMENT.4 EXPLANATION OF TERMS 1.
Valve Tag No - TMI valve tag number l
2.
Type - Valve type - gate valve or globe valve 3.
Size - Valve size in inches 4.
Position Normal - Valve normal position during plant operation 5.
Position Safety Action - Valve position after performing its safety function 6.
Design Basis DP Open - The calculated design basis differential pressure that the valve has to open against 7.
Design Basis DP Close - The calculated design basis differential pressure that the valve has to close against 8.
Design Basis Flow - The design basis flow at toe design baais differential pressure 9.
Available Valve Factor Open - A measure of the motor operator capability in the open direction based on motor undervoltage torque.
The standard industry thrust equation is used bat, instead of assuming a valve factor and solving for thrust, the thrust is determined from the motor undervoltage torque and the equation is solved for a valve factor which corresponds to that thrust output.
The available valve factor open is calculated as follows:
Thrust Open Calculated
- (Motor undervoltage torque
- Pullout ef ficiency)/ Stem f actor Available Valve Factor Open
- (Thrust-Packing load + Piston ef fect)/(Valve seat area *CP) 10.
Available Valve Faccor Close - A measure of the motor operator capability in the close direction based on the as-left thrust at torque switch trip. The standard industry thrust equation is usea but, instead of assuming a valve factor and solving for thrust, the thrust at torque switch trip is used and the equation is solved for a valve factor which corresponds to that thrust output. The available valve factor close is calculated as follows:
Available Valve Factor Close
= (Thrust STST Close-Packing load-Piston)/(Valve seat area *CP) 11.
Risk Factor - The priority ranking as listed in the TMI MOV Program Description 12.
Test DP - The differential pressure from the differential pressure test
ATTACHMENT 4 (Cont'd) 13.
Valve Factor 0/C - This is the back calculated valve factor from the differential pressure test open (0) and close (C).
N0 DP EFF indicates that the thrust trace did not show any thrust increase due to differential pressure 14.
Required Torque Ft-Lbs - The vendor required torque to operate the valve against the dp 15.
Available Torque Ft-Lbs @ TST - This is the as left value after testing i
l ATTACHMENT 5
)
VALVE GROUPING CRITERIA If a specific valve is not dynamically tested, the valve factor will be j
confirmed by utilizing data from dynamic tests of similar valves at TMI, other utilities or EPRI tests. At least 30% of the valves in the group must be tested with a minimum of two valves tested to establish a valve factor for the group.
Attribute Criteria Valve Type Same type: Gate, globe, butterfly Manufacturer Same manufacturer Configuration Gate valves must have same disc configuration, flex, solid, split, double or parallel Size Within 4 inches of the untested valve Pressure rating Same rating Mateiial Body, guide, disc and seating surface materials must be the same.
Test differential At least 60% of the TMI design dp pressure Valve factors measured by in-situ tests have a wide variation. Selection of the bounding valve factor is unrealistic in some cases. The valve factor will be selected by engineering judgement.