ML20149J411
| ML20149J411 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 02/29/1988 |
| From: | GULF STATES UTILITIES CO. |
| To: | |
| Shared Package | |
| ML20149J406 | List: |
| References | |
| IEB-85-003, IEB-85-3, NUDOCS 8802230044 | |
| Download: ML20149J411 (47) | |
Text
. _ _ _ _ _ _ _
GRE STATES UTILITIES CCMPMN RTVER BDO STATICN IE BULIETIN 85-03 PROGFAM REPORT FEBRUAPY, 1988 egg 22gggg gg8"ygge G
1.0 Background and Introduction On Novmber 15, 1985, NBC issued IE Bulletin 85-03, Motor-operated Valve Ctmnon bbde Failures During Plant Transients Due to Inproper Switch Settings.
In response to the bulletin, Gulf States Utilities prepared and ccupleted the IE Bulletin 85-03 Program for the River Bend Station. This report is subnitted in etnpliance with Action Itm (f) of the bulletin to present results of the River Bend I&E Bulletin 85-03 M Program.
1.1 Program Objective he objective of the River Bend I&E Bulletin 85-03 Program was to assure that the switch settings on bW operators under the bulletin scope were selected, set, and maintained correctly so that the M 's will operate properly over the entire range of differential pressures that might be experienced across the valves during both normal operation and abnormal events within the design basis of the River Dend Station.
te program scope enempassed FW's in the High Pressure Core Spray (HPCS) and the Reactor Core Isolation Cooling (RCIC) systes. 'Nenty-one (21) F W's (7 HFCS and 14 BCIC) were identified based on plant specific design data end the utilization of the BWR Owners' Group Report NEDC-31322.
Table 1 presents a listing of the twenty-one (21) FW's, and Figures 1 and 2 provide sinplified systs diagrams to illustrate these bW's and their functions.
1.2 Program Inpleentation and Results he design review and calculations identified the proper switch setting requirments.
We testing program was designed to dmonstrate M operability by verifying that these requirments were met.
Some bW maintenance / adjustments were performed to further enhance MOV performance and readiness.
Detailed discussions on M testing, results, adjustments, and operability are presented on an individual bW basis in Appendia A of this report.
2.0 IE Bulletin 85-03 Compliance GSM rmpliance with requirermnts of IE Bulletin 85-03 is described below.
2.1 Bulletin Action (a) required a design review of each bulletin valve to establish the naximum differential pressure expected during valve operation in design basis events.
his review was ccupleted and the results were subaitted to the NRC in a letter dated October 2,
1986 (RBG-24508).
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'Ib ensure that the GSU review methodology was consistent with generic IMA design basis and operating philosophy, GSU participated as a meber in the BWR Omers' Group IE i
Bulletin 85-03 Cmmittee. Based on input frun the BWR l
Owners' Group Report,- NEDC-31322, GSU performed a plant specific review to:
- 1) identify the River Bend bulletin MOV's and the associated design basis, and 2) calculate maximtn valve differential pressures for design basis events. 'Ihe differential pressure calculation methodology was consistent with the conservative asstmptions and techniques in the Owners' Group Report NEDC-31322.
2.2 Bulletin Action (b) required a review to establish the correct switch settings based on differential pressure i
calculations perforned in Action (a). CEU cmpleted this t
review and established switch setting requirments based on the following criteria, a)
The open position limit switch is used to stop p travel in the open direction. Its setting is designed to ensure that the valve will reach an open position to allcw full flow and stop before it becmes backseated. 'Ihe open position limit switch is used cm all bulletin valves at River Bend to stop the valve in the open direction. 'Ihe position limit switch is not used at River Bend to stop any bulletin valve in the closed direction.
l b) Torque switch bypasses are used to prevent the p I
i frcm de-energitation by torque switch actation.
I River Bend's design philosophy is to byInss the torque I
switch for the safety direction (s) of the valve for 95% of valve travel to ensure that the valve will perform its safety function, i
Both the open position limit and the torque switch bypasces are operated by geared rotors.
These switches are set in accordance with River Bend Maintenance Procedure CNP-1253.
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c) 'Ibrque switches am used on River Bend bulletin MOV's to provide stop control in the closed direction and as backup to the open position limit switch to stop the a in the open direction. Settings for these torque switches were controlled by River Bend Maintenance Procedure CNP-1253 prior to the availability of thrust signature testing techniques.
CNP-1253 provides mininum and maximum torque switch settings that were based on torque switch calibration data provided by Limitorque, i
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d) Thernal overloads for all bulletin KN's are bypassed ktw1 the p is autmatically operated in design basis J
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events. The design of their control circuits provides this autamtic feature. If the notor trips due to the operation of the thermal overloads during a manual initiation, operations personnel nuy bypass the thenul overloads and restart the notor by holding the valve control switch in the desired direction of travel.
7hese criteria were verified by a review of design documents and torque switch settings vs. torque output data provided by Limitorque.
In addition, torque switch setting calculations wre performx! to determine required setpoints in stem thrust for use as the criteria in setting torque switches during thrust signature testing.
Based on the review of design documents, finitorque data, and calculations, all bulletin FW's were determined operable with respect to canpliance with the abwe stated criteria.
2.3 Bulletin Action (c) required dmonstration of valve operability by testing at calculated maximum differential pressures.
For cases where testing with maximum differential pressure cannot be practically performed, justification including alternative means of switch setting verification shall be provided.
The River Ibnd IE Bulletin 85-03 Program objective was to test the bulletin FW's at full flow maximum differential that could be achieved without jeopardizing equipmnt operability and plant safety. An engineering review cf the bulletin valves and the maximum differential pressure conditions was conducted to determine the best test method to verify correct switch settings. A major consideration in this review was whether or not it was practical or safe to establish systen conditions and configurations that would be required for full flow differential pressure testing. An engineering evaluation of the testing methods was also performed in view of the very low calculated differential pressures associated with som valves.
7hree test methods wre chosen:
- 1) Full flow differential pressure testing, 2) Differential pressure testing with hydrostatically established pressure, 3) 7hrust signature testing using signature analysis devices and techniques.
As a rhinimum, thrust signature testing was perforned for all bulletin valves.
Full flow differential pressare testing was performed on seven FN's (4 RCIC and 3 HPCS).
Hydrostatic differential pressure testing was Erzformed on tw HPCS F W 's and one RCIC F M. 7he testing methods and basis are presented in detail in the form of individual FW testing and operability simraries contained in Arpendix A, as well as in a tabular forwit in Appendix B.
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2.4 Bulletin Action (d) required procedures to ensure correct switch settings are maintained throughout the life of the plant.
Procedure CNP-1253 currently provides control of switch settings.
Based on this M progrm, CNP-1253 has been reviewd to ensure that switch setting values and instructions are clearly specified.
A torque switch balancing section was added to CNP-1253 as a result of this effort.
Since the torque switch trip points for the bulletin valves were verified with signature testing, River Bend will use signature testing techniques to re-verify proper switch settings for the bulletin valves after major maintenance affecting MW thrust settings and capabilities is performed. Such maintenance includes the adjustment or replacement of the torque switch, spring pack, actuator drive train, or valve internals.
2.5 Bulletin Action (e) required the subnittal of a written report to address results of Bulletin Action (a) and a program plan including the schedule for empletion of Actions (b) thrcugh (d). GSU met this requirment by a letter transnitted to the NRC on October 2,
1986 (RBG-24508).
2.6 Bulletin Action (f) required a written report of the above progrm. This report satisfies that requirement.
As requested, this report provides (1) a verification of the ccmpletion of IE Bulletin 85-03 requirements, (2) a sunmary of findings regarding valve operability prior to any adjustments, and (3) a sunmary of data required to evaluate the response to the bulletin, 3.0 7bsting Program and Results 3.1 Plow Testing Program the application of full flow testing was evaluated for each valve based on equipaent/ plant operating and safety constraints.
If full flow testing was determined inpractical, differential pressure testing with hydrostatic pressure was considered. For those MW's with low differential pressure thrust ecmponents, only static thrust signature testing was performed based on engineering evaluation.
Based on the above considerations, full flow testing was perforned for four (4)
Flow testing with hydrostatic pressure was performed on one (1) PCIC and two (2) HrCS valves.
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RCIC valves 13, 19, 22, and 59 were full flow tested prior to unit shutdown for the refueling outage. HPCS valves 1, 10, and 12 were full flow tested during the refueling outage.
Flow testing with hydrostatic pressure was performed c'uring the outage for RCIC 013, and HPCS 04 and i
15.
3.2 Signature Testing Program All the bulletin n's were signature tested, as a mininun under static conditions.
Signature = testing was aloo performed for one RCIC MOV and five HPCS M 's under differential pressure conditions.
The signature testing technique used in the River Bend 7bst Program provides measurment of spring pack novement for calculation of stem thrust associated with torque switch settings. The use of signature test data allows the detemination of available sts thrust provided by the torque switch settings to operate against differential pressure conditions. Motor current, and applicable limit swi*ches (position limit and bypasses) are also nonitored L
during the signature test.
l A signature testing systs offered by Inpell Corporatien was used on the bulletin M 's.
A technical description of the CATIS syste is provided in Appendix C.
l 3.3 Test Results Rased on differential pressure testing and signature r
- testing, all balletin MOV's were evaluated for operability.
Detailed test results, evaluation criteria, and operability discussions are provided in Appendix A.
The maxinun differential pressures given in the individual Appendix A E strearies were calculated based on asstriptions and techniques frm the EER Owners Group l
Report NEDC-31322. The mininun required sts thrust given was calculated using standard valve vendor equations and i
valve factors provided by Limitorque, and packing load data provided by the valve suppliers.
The maxinun j
available stm thrust given was calculated assuming 80% of the ncminal voltage to the motor.
i 2he mininun and maxinun thrust criteria were used as a reference to verify torque switch thrust trip points, i
They were not absolute criteria for determining valve l
operability because of conservatism and variability inherent in the calculation assunptions.
Each p was evaluated for operability based on a review and emparison of applicable data such as torque switch setting in 1
relation to Limitorque torque switch calibration data, l
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reasured thrust trip points in relation to running load and spring pack preload, full flow and differential pressure test data, etc.
hm specific operability criteria that wre used are discussed in the individual sumaries in Append 1>: A.
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7 TABLE 1 I
The RBS IE Bulletin 85-03 Program The mr,ximum expected differential pressures were provided to the NRC in our Cetober 2, 1986 letter and are tabulated here for convenience, e
F12CFIG6 dP_
dP E22*F001 16" Cato A/D CST Suction Valve (a) 131 r
E22*F004 10" Gate A/D Injection Valve 1423 1486 E22*F010 10" Globe A/D CST hst Return (a) 1431 i
E22*F011 10" Globe A/D CST h st Return (a) 1431.
E22*F012 4"
Gate A/D Min Flow Valve 1446 1608 E22*F015 20" Gate A/D Sup Pool Suction 94 17 E22*F023 10" Globe A/D Sup Pool Return (a) 1431 E51*F010 6"
Gate Velan CST Suction (a) 71 E51*F013 6"
Gate Velan Injection 1371 1546 E51*F019 2"
Globe Velan Min Flow Valve 1455 1469 E51*F022 4"
Globe Velan CST Test Return (a) 1430 E51*F031 6"
Gate Velan Sup Pool Suction 19 17 E51*F045 4"
Globe Velan Turb Steam Supply 1165 1165 E51*F046 2"
Globe Velan Inbe Oil Cooler 1386 (a)
E51*F059 4"
Gate Velan CST Test Return (a) 1430 E51*F063 8"
Gate Velan Inbd Steam Isol (a) 1165 E51*F064 8"
Gate Velan outbd Steam Isol (a) 1165 E51*F068 12" Gate Velan Steam Dischg V1v (a) 8 E51*F076
.75" Globe Velan Line Waming Viv (a) 1165 E51*F077 1.5" Globe Velan Vacuum Bkr Valve (a) 23 E51*F078 2.5" Globe Velan vacuum Bkr valve (a) 23 (a) The valve has no safety function in this direction.
MOV F004 CONDENSATE TD g /
kJ STORAGE TANK RX 77 (CST)
~
Aus>>>_
HOV HOV HOV z
F023 F010 F011 w2 w_a w_a V'M V3 V3 MOV F012 L2 73 HPCS RV F014 PUMP) s s s
v>9uJJJa SUPPRESSION I
)
POOL MOV MOV F015 VF016 VF002 F001 7
~
~
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Figure 1.
HPCS System P & ID
l CONDENSATE STORAGE TANK 1
(CST) s
-JJJJJ n kJ 07 F059 LUBE O!L COOLER f
1 7 HOV HOV ADV ADV MOV j, F022 F046 F066 F065
, F013 MOV F010 R
g PUHP W
RV V FC17 MOV O
[0g r,
O f-. VF011 o
SUPPRESSION POOL MOV F031 VF030 7
0 i
Figure 2.
RCIC System P & ID i
X LINE MOV F076 wa
- %e r,
HYV MOV C002 F045 RCIC TURBINE
./
s, MOV MOV VF040 F078 VF082 VF080 F077 Y~~1
~
t MOV F068 w_1 i11.
o SUPPRESSION POOL Figure 2 (Con' t).
RCIC System P & ID i
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APPDOIX A SW9RRY & MN 'IESI'DE, PESUIRS NO OPERMIIIJTY
'IESTING MO OPERhBILITY SLNGutY Valve ID:
E22*F001 Type & Size:
16" 150 lbs Anchor Darling Gate Operator:
Limitorque SMB-00-10 Motor:
480 VAC 1700 RPM 0.7 Hp Valve Function:
HPCS Suction Fran the CST ra rm1=ted Mari== Diffezetial Prmanner Closed /131 psi Open/N/A Minisama Requirsd Stamt ' thrust namad m Cifferential Pressure Pistm Effect, and Packing Ioad:
8439 lbs Maximaan Available Stena ' thrust namaa on 80% Available vbltage 11954 lbs Testing Perframwl and Basis:
A full flow thrust signat'1re test was conducted in which the M W was operated closed and open against differential pressure conditions duplicating those upon which the calculations were based.
mis differential pressure was acnieved by closing F001 as scon as F015 started to open with the HPCS pmp running. me flow test duplicated the design basia conditions by establishing a final differential pressure of 23 psi and an initial flow rate of 5000 gpn. me calculated differer.tial pressure of 131 psi was based on 17.3 psi (due to CST and suppression pool static head difference) + 113 psi (differentihl pressure associated with fluid deceleration due to valve closure),
he fluid deceleration differential pressure ccaponent could not be reasured becTuse of instrunentation limitations. However, che flw conditions and the stroke time used in the calculation were duplicated. me calculation was based on approxitately 5400 gpn and a stroke time 71.6 sec. We actual flow during the test was 5000 gpn and the stroke time was 74.56 sec. Thrust signature testing was performed at static conditions to detennine torque switch and limit switch actuations.
3 As Fbund Conditions:
'Ibrque switch settings of 1.0 and 1.0 were found which produced thrust trip points of 8.0 and 4.75 K1bs for the closed and open directions, respectively. Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Adjustau!nts/ Actions Performed:
We torque switch was balanced and settings adjusted frun 1.0 to 1.5 to obtain higher trip points.
As Ieft Otru11tions:
As-left torque switch settings of 1.5 and 1.5 produced thrust trip points of 9.5 and 11.8 Klbs for the closed and cpen directions, respectively.
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Valve ID: E22*F001 Crerabuity avelustian 'the M ms determined operable. W flow test was performed after the torque switch adjustraent. 'therefore, valve operability was verified for the as-left conditions. A review of the full flow signaturv data and the as-found data also indicated the M m s operable before the torque switch adjustment. A 4.36 K1bs spring pack preload as measured indicating an avallable thrust margin of 8.03 K1bs to close against the thrust L
requirement. Since t}r maximta thrust observed during valve closing for the full flow test was 5.7 Kib, the as-found available thrLat margin would have been adequate to close the valve against full flew conditions.
'the as-found open torque switch trip point (4.75 K1bs) had no operability inpact because the torque switch as bypassed for greater than 90% of stroke time.
Adjustments that wre made further enhanced valve performance by increasag the thrust margin as evidenced by the as-left data.
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7ESTING AE ORNRII.ITY SEDMUtY valve ID:
E22*F004 Type & Size: 10" 655 Lbs Anchor Darling Gate operai:or Limitorque SB-3-80 mtor 480 VAC 3380 RIH 10.3 Hp Valve Function:
HPCS Injection Valve Calculated Mart== Differintial Pressure: Closed /1486 psi open/1423 psi Mininam Required Staa Wrust Ramaa m Differential Pressuts, Pistm Eff').:t, and Packing Ioad:
_31_366 lb_s Mart== Available Stm Wrust Duned on 80% Availah1.e vbitage:
45760 lbs Testing Perfomed and ansim:
A differential pressure flow signature test was conducted in which the mV was operated open against a
hydros,tatic differential pressure of 1555 psi.
We flow test data indicated that the differential pressure accounted for atout 27,000 lbs of thrust during the first mments of valve opening.
Wis finding further validates the engineering calculation for thrust requir ments. Full ficw tetting of F004 could not be practicably performed because it is the injection valve to the reactor vessel. Brust signature testing was perforned at static conditions to determine torque switch and limit switch actuations.
As Found Cbnditions:
7brque switch settings of 2.1 and 2.0 were found which produced thrust trip points of 71.03 and 67 Klbs for the closed and open directions, respectively.
Both torque switch bypasses w re set at greater than 90% of their respective stroke times, a
Adjustments / Actions Iwrformd:
We torque switch settings were adjusted fran 2.1 and 2.0 (closed and cpen) to 1.5 (for both) to obtain trip point values that would be nore consistent with the calculated maxinum available thrust under degraded voltage conditions.
As Ieft Ciriditims:
As-left torque switch settings of 1.5 produced thrust trip points of 47.91 and 45.35 Klbs for the closed and open directions, respectiw ly.
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Valve ID: E22*F004 operability Evaluation:
The M was determined operable. The torque switch trip points provided more than adequate thrust to open and close the valve.
Although higher than expec'.ed thrust was observed, the M operated much below the operator's 140 Klbs thrust limit. %e as-found trip points were evaluated with respect to the calculated maxinun available thrust under degraded voltage. Wis evaluation demonstrated M operability based on the following.
Using torque switch settings vs torque values provided by Limitorque, recalculation of the stem factor was performed based on the actual measured trip points and torque switch settings.
Wis was valid since the torque switch tr;p points indicated a balanced torque switch. A revised stem factor of 0.01258 was calculated as follows. A torque switch setting of 2.1 would result in a torque trip point of 894 ft-lbs (based on the linear relationship that torque switch settings of 13/4 to 2 3/4 are equivalent to 704 to 1248 ft-lbs). This torque divided by the measured sten thrust is the revised stem factor (894/71030
.01258).
mis revised stan factor would change the
=
calculated maxinun available thrust under degraded voltage fran 47560 lbs to approximately (993/0.01258) 78.9 Klbs. Based on this, the M would have
=
tripped going closed under degraded voltage conditions.
For the open direction, the limit switch would stop the M. %erefore, the high torque switch trip point was inconsegaential.
Adjustments that were made further enhanced valve perfornance by decreasing operating stresses and making the torque switch trip points acre consistent with the calculated available thrust under degrwied voltage conditions.
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'11? STING MD OPERARTT. TTY SG99M Valve ID:
E22*E010 Type & Size: 10" 900 Ibs Anchor Darling Globe Operator:
Limitorque SMB-4-200 mtor:
480 VAC 1700 REM 13 Hp Valve Functicm:
HPCS Test Return to the CST Calculated Maxi== Differential Pressure: Closed /1431 psi Open/N/A Mini== Required Stan % rust Based on Differential Pressure, Piston Effect, and Packing Inxl:
91992 lbs Mav4== Available Sten Brust Baseci on 80% Available Voltrge:
169493 lbs Testing hiuuwd and Basis:
A full flow thrust signature test was conducted in which the bOV was operated closed against a differential pressure of 1090 psi which was the maximum that could be practicably obtained based on approved test procedures. he flow test maximized the differential pressure across F010 by isolating all fic9 paths frm the HPCS pump discharge except for the minimum f'ow line and the test return line, and by placing F011 (downstream of F010) in the full open position. This duplicated the design basis conditions with the exception of F012 (minimum flow) which was required open for punp protection during the test. trust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
As Pound enditicos:
7brque switch settings of 2.0 and 2.0 were found which produced thrust trip points of 182.7 and 192.93 Klbs for the closed and open directions, respectively. The bypass for the closed torque switch was set at 78% of stroke.
The bypass for the open torque switch was set at 9.5% of stroke time.
Adjustments / Actions hn-- 1:
We torque switch settings wert..:djusted frm 2.0 and 1.75 (closed and open) to obtain trip point wlues that would be nere consistent with the calculated maximum available thrust under degraded voltage conditions.
We bypass for the closed torque switch was reset to 94% of stroke time (frm 78%). This was done to give additional protection margin to ensure valve is near the closed position before the torque switch is trade ective. The bypass for the open torque switch was reset to 6% of stroke time (frm 9.5%).
%is was done to ensure the valve closed position light (red light to de-energizai does not de-energize until the valve is very close to being seated (both contacts en the same rotor).
As Ieft Otnditions:
As-left torque switch settings of 1.75 and 1.75 l
produced thrust trip points of 129.47 and 136.26 Klbs for the closed and open directions, respectively. he bypass for the closed torque switch was left at t
94% of stroke tine and the bypass for the open torque switch was left at 6%.
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Valve ID: E22*F010 Operability Evaluatim:
The bOV was detennined operable, h flow test data indicated that 83 Klbs was required to overcme a differential pressure of 1090 psi for closing. %erefore, the extrapolated thrust requirement for 1431 psi (design basis) _ is 1431/1090 X 83K = 108.9 Klbs, since thrust is linearly proportional to the differential pressure and the valve factor.
Based on this, the torque switch trip points provided nore than adequate thrust to open and close the valve.
Because as-found trip points showed higher than expected thrust, General Electric was requested to review the original stress analysis for inpact.
Their review indicated valve operability, but reccamended a visual inspection of the sten clanp key. The inspection of the stem clamp key and stem clamp revealed no apparent damage.
te torque switch settings were reduced to decrease ccmponent stresses, h as-left open torque switch bypass setting of 6% of stroke time has no inpact on operability because the torque switch setpoint is sufficiently high and the valve has no safety function to open.
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'IESTING APO OPERARTT. TTY SGNUE Valve ID:
E22*F011 Type & Size:
10" 900 lbs Anchor Darling Globe Operaku :
Limitorque SMB-4-200 Motor:
480 VAC 1720 RMI 13 Hp Valve FLmetim:
HECS Test Return to the CST f'almlated MaFine Differential Pressure Closed /1431 psi Open/N/A Minimm Required Stan Brust Raaarl on Differential Pressure, piston effect, and packing load:
91992 lbs Maximm Available Stan Wrust Raaerl on 80% available voltage:
169493 lbs Testing Perfnmari and Basis:
Flow testing data fran F010 was used to denonstrate F011 operability because both bm's were identical in design and application.
t urst signature testing was performed at static conditions to determine torque switch and limit sw ch actuations.
As Fourxl Canditims:
Torque switch settings of 2.25 and 2.25 wre found which produced thrust trip points of 132.33 and 130.65 Klbs for the closed and open directions, respectively. We closed torque switch bypass was set at 90%
of stroke. W e open torque switch bypass was set at 0.7% of stroke time. %e open position limit switch was set too close to the backseat resulting in 99.9 K1bs of sten thrust to the backseat.
Adjustments / Actions Pein -- i:
% e torque switch settings were adjusted frcm 2.25 to 2.1 (both closed and open) to obtain lower trip points.
%e open position limit switch was adjusted to eliminate backseating.
As left Conditims:
As-left torque switch settings of 2.1 and 2.1 produced thrust trip points of 111.27 and 113.83 Klbs for the closed and open i
directions, respectively. Backseating was eliminated.
Operability Evaluatim:
The FDV was determined operable. Based on F010 flow data,108.9 Klbs of thrust was required to close against 1431 psid.
Both as-found and as-left data indicated MOV operability. The as-found and as-left torque switch trip points provided nore than adequate thrust to open and close the valve.
The open tongue switch bypass setting of 0.7% of stroke time has no impact on operability because the torque switch setpoint is sufficiently high and the valve has no safety function to open. The as-found backseating condition did not affect operability since the valve was operated satisfactorily during thrust signature testing.
mis condition was also evaluated by General Electric. Weir review of the original stress analysis indicated the stress was below design and that valve operability was not affected. Adiustments that were made further enhanced valve performance by eliminating i ackseating and lowring operating stresses to the FM ccrrponents.
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'IESTING APO OPERARTT. TTY SGNUtY Valve ID:
E22*F012 Type & Size:
4" 900 lbs Anchor Darling Gate Operator:
Limitorque SB-0-25 Motor:
480 VAC 3400 RH4 3 Hp Valve Function:
HPCS Min Flow to the Suppression Pool Palm 1ated Maximm Differential Pressure: Closed /1608 psi Open/1446 psi Minimum Required Sten % rust Based
(
on Differential Pressure, Piston Effect, l
and Packing Ioad:
9878 lbs l
l Maximm Available Stem %Iust Based on 80% Available Voltage:
13349 lbs Testing Perfnmad and Basis:
A full flow thrust signature test was conducted in which the valve was closed and opened against a differential pressure of 1140 psi and 520 psi, respectively. mese differential pressure conditions were the maximum that could be achieved based on approved test procedures.
The flow test initially naximized the HPCS discharge line pressure by isolating all paths except for F012 to the suppression pool. F012 was required to be open for pmp protection. F023 was then throttled open, hence causing F012 to autmatically close. A differential pressure of 1140 psi was recorded across F012 after it was closed.
Maxinun opening differential pressure was achieved by closing F023, hence causing F012 to open.
520 psi was recorded prior to closing F023. %erefore, actual differential pressure that the valve opened against was higher than 520 psi.
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
As Found Chnditions:
Torque switch settings of 1.75 and 1.5 were found which produced thrust trip points of 20.39 and 5.3 Klbs for the closed and open directions, respectively. %e closed and open torque switch bypasses 3
were set at 85% of stroke times.
24 Klbs of backseating was observed.
Adjustments / Actions Pedon-i The open position limit switch was adjusted to elinunate valve backseating.
We torque switch settings were first lowered, then readjusted to the approximate original settings to ensure valve seat tightness.
As Ieft Corvittions:
As-left torque switch settings of 1.75 and 1.5 produced thrust trip points of 18.19 and 8.62 Klbs for the closed and open directions, respectively.
Due to the open position limit switch adjustnent which shortened the stroke times, the as-left bypass settings were 97% and 85% of stroke tinus for the open and closed torque switches, respectively.
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, valve ID: E22*F012 4
Oparahi1ity Evaluation: - Se M was determined operable.
%ere was more tun adequate thrust in the closed torque switch trip points (20.39 K.as-found and 18.19 K as-left) to close the valve. Based on the flow data, a thrust. of
' 9.3 Klbs was observed during the test for overtoning the differential pressure effects..%e differential pressure that was overcame was the recorded differential pressure (1140 psi) plus the fluid deceleration differential pressure upwnt of -181 poi that was not recorded because of instrunent limitation.
21s deceleration cw w.ent was part of the total inaxinnan calculated differential pressure. %erefore, using an effective differential pressure of 1321 psi (1140 + 181) and the measured required thrust of 9.3 K1bs, a required thrust of 11.32 Klbe was extrapolated for a differential
' pressure of 1608 psi. Valve opening was assu m i because the torque switch was bypassed for 85% of stroke time. We backseating condition was evaluated by General Electric via a review of the original stress analysis. Wis review indicated valve operability and recormended a liquid penetrant test of the backseat in the next scheduled valve maintenance of F012. %e open position limit was adjusted to eliminate backseating.
We closed torque switch trip points of 20.39 and 18.19 K1bs were evaluated with respect to the calculated available thrust of 13349 lbs under degraded voltage.
his evaluation demonstrated M
operability based on a
recalculation of the stem factor using Limitorque-provided torque switch data and the as-found measured thrust. % e torque switch settings were 1.5 and 1.75 for the closed and open directions. Limitorque data indicated a 1 3/4 setting would. yield 144 ft-lbs for F012. Since the thrust data indicate a unbalanced torque switch, the stem thrust at 1.75 setting was calculated as (20.39 + 5.3)/2 = 12.84 K1bs. A new stem factor of 0.0112 was calculated based on (144/12840 = 0.0112). Using this stem factor, available thrust at degraded voltage was recalculated as 217.6/.0112 19403 lbs _ which
=
denonstrated that the as-left trip point would stop the M under degraded
- voltage, m
L t
B
)
L 9
1 j
TESTING MO CPERABILITY SGMAl&
Valve ID: E22*F015 Type & Size:
20" 150 lbs Anchor Darling Gate Operator: Limitorque SB-1-40 Motor:
480 VAC 3450 RIN 5.3 Hp valve Functim:
HPCS Suction frm the Suppression Pool MaM== Differential Pressure: Closed /17 psi Open/94 psi Mininun Required Stem % rust Based on Differatial Pressure, Pistm Effect, and Packing Ioad:
3967 lbs MaM== Available Stan Brust Based on 80% Availahie Voltage:
21281 lbs Testing h-D-- i and Basis:
A differential pressure flow signature test was conducted in which the M3V was operated open against a hydrostatic' differential pressure of 63.3 psi. %is was the maximum pressure that could be practically achieved because of proximity to the pump suction relief valve (RVF014) setpoint of 90 psig.
Thnist signature testing was performed at static conditions to determine torque switch and limit switch actuations.
As Pbund (bnditions:
Torque switch settings of 1.5 and 1.5 were found which produced thrust trip points of 18.8 and 19.04 Klbs for the closed and open directions, respectively. The closed and open torque switch bypasses were set at 94% and 96% of their respective stroke times.
Adiustments/ Actions hL-- 1:
The torque switch settings wre lowered slightly frm L5 to 1.4 (both closed and open) to obtain lower trip points.
As Ieft Conditions:
As-left torque switch settings of 1.4 and 1.4 produced thrust trip points of 14.81 and 14.86 Klbs for the closed and open directions, respectively.
Operability Evaluation: The MW was determined operable. The as-left closed torque switch trip point of 14.81 Klbs represented available thrust to operate against differential pressure since a spring pack preload of 6.41 K1bs was neasured.
%e as-left available thrust (14.81 Klbs) was significantly larger than the calculated differential pressure thrust requirment of 1226 lbs. The as-found torque switch trip points provided even nere margin (18.8 Klbs vs l225 lbs) to operate against design differential pressure conditions.
- djustments that were unde enhanced performance by decreasing valve operating stresses.
10
'ESTDIG ARO OPERARTT. TTY SEMRRY Valve ID:
E22*F023 Type & Size:
10" 900 lbs Anchor Darling Globe Graium:
Limitorque SMB-3-150 Motor:
480 VAC 1655 RPM 10 Hp Valve Function:
HPCS Return to Suppression Pool Iturium Differential Pressure:
Closed /1431 psi Open/N/A Mini== Required Stm % rust Raaarl m Differential Pressure, Piston Effect, and Packing Inad:
91930 lbs Maximm Avai]2hle Stm Brust Raasvi on 80% Available Voltage:
127,126 lbs Testing Perfnruad and Basis:
Flow test data fr m F010 was used to detonstrate operability for F023 because F010 and F023 were identical in valve design.
In addition, the flow test perforned for F012 required F023 to close against the maxinum testing differential pressure conditions, which further detonstrated bOV operability.
% rust signature testing was performed at static conditions to determine torque switch and limit switch actuations, As Found Conditions:
ToIque switch settings of 3.0 and 2.0 were found which produced thrust trip points of 104.9 and 123.87 Klbs for the closed ard open directions, respectively. The closed torque switch bypass was set at greater than 90% of stroke tine.
We open torque switch bypass was set at 7% of stroke time.
Adjustments / Actions Performed:
None As Ieft Conditions:
Same as As Found (bnditions.
Operability Evaluatim: The bOV was determined operable. %e torque switch
)
trip points were adequate to operate against expected differential pressure conditions. Based on F010 flow test data, it was conserv..tively calculated that approximately 108.9 K1bs would be needed to close against 1431 psid.
Although the F023 torque switch trip point was marginally smaller, total thrust (i.e.,
including inertial load) was 124 Klbs which would give additional assurance for valve closing.
F0V operability was further demonstrated by the F012 full flow test.
In the F012 flow test, test conditions detonstrated that F023 will close, although the differential pressure achieved was less than the calculated nuxinum.
The calculated maximum was based on a very conservative assumption that F012 had not yet opened when F023 closed. His assumption was proven unrealistic by the F012 flow test which danonstrated that as F023 started to close, F012 autmatically opened.
11
'IESTING MO OPEIRBILITY SDNUE Valve ID: E51*F010 Type & Size:
6" 150 lbs Velan Gate Operator: Limitorque SMB-00-10 letor:
125 VDC 1900 RPM 0.72 Hp Valve Function:
RCIC Suction frun the CST 61mlated Maximaan Diffierential Promette: Closed /71 psi Open/N/A Mini== Required Stm Thrust Based on Differential Pressure, Pistm Effect, and Packing Ioad:
3887 lbs Maxinaan Availahla Stan ihrust Based m 80% Available vbltage:
9024 lbs Testing Perfnrund and Basis:
Thrust signature testing was performed at static conditions to detemine torque switch and limit switch actuations.
No flow testing was performed because of the low differential pressure value and its asu:ciated low thrust requirment (529 lbs calculated).
This calculated differential pressure thrust requirement' represents less than 15% of the overall thrust requirment for valve closing. This basis is further supported by the as-found conditions shown below which indicate significant margins in both torque switch trip points to acccmodate design differential pressure conditions.
As Pbund Canditims:
Torque switch settings of 2.0 and 2.0 were found which produced thrust trip points of 8.03 and 10.04 K1bs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Adjustments / Actions Peu.G - 1:
None a
As Ieft Conditims:
Same as As Etund Conditions Operability Evaluatim: The FOV was determined operable.
A review of the as-found closed torque switch trip pint and maxinum running load indicated a thrust margin of at least 4280 lbs to close against the calculated thrust requirements of 529 lbs for differential pressure, and 176 lbs for line pressure. The open torque switch provided even nere nargin. The open torque switch trip point was evaluated with respect to the maximum available thrust under degraded voltage. It had no impact on F0V operability because the MOV would be stopped by the limit switch in the open direction.
12
'IESTI!G MD TERARTT. TTY S(M1ARY Valve ID:
E51*F013 Type & Size:
6" 900 lbs Velan Gate Operator:
Limitorque SMB-0-40 Motor:
125 VDC 1900 RPM 2.9 Hp Valve Functim:
RCIC Injection to the Reactor Maxi== Differatial Pressurt.:
Closed /1546 psi Open/1371 psi Mini== Required Sten % rust Based on Differential Pressure, Piston Effect, and Packing Ioad:
18594 lbs Maximnq Available Stan 'Ihrust Based m 80% Available vbltage:
19620 lbs Testing FwS-d and Basis:
A full flow test with notor anp signature was conducted in which the bW was operated closed and open against differential pressures of 800 and 890 psig, respectively.
Because of instrunent limitation, these recorded differential pressure data did not include approximately 175 psi of the fluid deceleration ccrnponent of the maxinun calculated differential pressure.
Adding the 175 psi to the recorded differential pressure would result in an effective differential pressure of 975 psi for closing. W ese full flow differential pressure conditions wre the maximum that could be practicably obtained during the reactor shutdown /depressurization process for the refueling outage. We valve line-up for the test maximized the differential pressure betwen the RCIC punp discharge and the reactor by isolating all discharge flow paths except for l
minimum flow (F019) and the lube oil cooler (F046). The calculated maximum l
closing differential pressure was based on a conservative assunption that F019 i
had not started to open when F013 closed. This condition was not duplicated l
because it would have jeopardized punp operability.
A hydrostatic differential pressure thrust signature test was also conducted in which the FDV opened against differential pressures of 750 and 1450 psi.
Thrust a
signature testing was performed at static conditions to determine torque switch and limit switch actuations.
l As Found Conditim s:
Torque switch settings of 2.125 and 2.0 were found l
wttich produced thrust trip points of 18.97 and 16.45 Klbs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Ad_justments/Actims Performed:
None d
As Ieft Conditims:
Same as As Found Conditions Operability Evaluatim:
The F W was determined operable. The torque switch trip points wre adequate. Hydrostatic differential pressure test results also indicated that the valve could be opened against 1450 psid.
In addition, the static signature test results indicated an inertial load of greater than 12 K lbs attributable to the fast operation of the valve. Wis inertial load further ensures that the valve will close against design differential pressure conditions.
13
'IESTING APO OPERARTT. TTY SU99JtY Valve ID: E51*F019 Type & Size:
2" 1500 lbs Velan Globe Opei.aku.: limitorque SMB-00-10 Motor:
125 VDC 1900 RIN 0.72 Hp Valve Function:
RCIC Minimum Flow to Suppression Pool Mari== Differatial Pressure:
Closed /1469 psi Open/1455 psi Mini== Required Stan @ rust Based m Differential Pressure, Piston Effect, and Packing Ioad 5640 lbs Mari== Available Stan % rust Based on 80% Available Voltage:
9736 lbs
'riesting Perfn-d and Basis:
A full flow differential pressure test was conducted in which the tin was operated closed and open against a differential pressure of 1605 psi.
The test differential pressure was higher than the calculated maximum because test conditions established were nere conservative than the design basis assumticns. The differential pressure calculation was based on the assumption that F019 closed when flow in the main line was equal to the required mininum flow rate.
The actual flow test conditions established were that F019 closed with no other flow path except for the lube oil cooler flow.
Tnerefore, a test differential pressure higher than the calculated was obtained. Wrust signature testing was perforned at static conditions to determine torque switch and limit switch actuations.
As Pbund Conditims:
Torque switch settings of 1.25 and 1.25 mre found which produced thrust trip points of 5.73 and 4.97 Klbs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke tines.
Adjustments /Actims Perfuumzi None As left Conditions:
Same as As Found Conditions Operability Evaluation: We MN was determined operable.
A spring pack preload of 1.47 Klbs was neasured, which indicated an available thrust of 5.73 Klbs to close against the calculated differential pressure thrust requirmnnt of 2855 lbs.
We full differential pressure test further supports this conclusion.
l t
14
A Valve ID:
E51*F022 Type & Size:
4" 900 lbs Velan Globe i
Operator:
Limitorque SMB-0-10 Motor:
125 VDC 1900 RPM 0.72 Hp Valve Function:
RCIC Test Return to the CST May h m Differential Pressure:
Closed /1430 psi Open/N/A Minh= Required Staa 'Hirust Ramd on Differential Pressure, Pistcri Effect, and Packing Ioad:
12505 lbs Maxinaan Available Stan 'Dirust Ramvl on 80% Available Voltage:
17426 lbs Testing Bernwnmi and nania:
A full flow differential pressure test was conducted in which the MN was operated closed and open against a differential pressure of 1498 psi.
The differential pressure produced by the test was consistent with the calculated maxinun. We strall variance was attributable to expected reading errors associated with analog gauges. trust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
As Found Cbnditions:
Torque switch settings of 2.75 and 2.75 were found which produced thrust trip points of 15.1 and 16.72 K1bs for the closed and open directions, respectively.
%e bypass for the closed torque switch was set at greater than 90% of stroke time. We bypass for the open torque switch was set at 3% of stroke time.
Adjustments /Actims Fmnummh None As Inft Oonditions:
Same as As Found Conditions Operability Evaluation: The MN was determined operable. A cmparison of the torque switch trip point and the running load indicated an available thrust of approximately 11.6 Klbs to close against the calculated differential pressure thrust requirenent of 9395 lbs. The full differential pressure test further supports this conclusion.
The bypass setting for the open torque switch is per design since the valve has no safety function to open.
15
'IFEI'ING APO OPERABILITY S0MMARY Valve ID:
E51*F031 Type & Size:
6" 150 lbs Velan Gate Operatnr:
Limitorque SMB-00-10 Motor:
125 VDC 1900 RPM 0.72 Pp Valve Ibnction:
RCIC Suction frm the Suppression Pool calculated Maxinam Diffm.cutial Pressure:
Closed /17 psi Open/19 psi Minina= Required Stan Thrust namaa on Differential Pressure, Pistra Effect, and Pa': king Ioad:
3484 lbs Maxima Available Sten 'Ihrust Ramad on 80% Available vbltage:
9040 lbs Testing Perfmuad and nania:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow testing was performed because of the calculated low differential pressure thrust requirment of 126 lbs. This calculated differential pressure thrust requirement represents less than 4% of the overall thrust.Wt for valve closing. This basis is further supported by the as-found conditions shown below which indicate significant margins in both torque switch trip points to accmodate differential pressure conditions.
As Found Conditions:
Torque switch settings of 2.0 and 1.5 were found which produced thrust trip points of 6.51 and 8.84 K1bs for the closed and open directions, respectively. Both torque switch bypasses were set at greater than 90% of their respective stroke tines.
Adjustnents/ Actions Pm.nnw 1:
None As Ieft conditions:
Same as As Found (bnditions f
Operability Evaluatim:
'Ihe MN was determined operable. A cmparison of the torque switch trip point and the running load indicated an available thrust of approximately 4.8 Klbs to close against the calculated differential pressure thrust regttirement of 126 lbs and line pressure thrust requirment of 176 lbs.
1 1
l l
{
16
TESTING A!O OPERABILITY S[DMARY Valve ID: E51*F045 Type & Size:
4" 900 lbs Velan Gate Operator: Limitorque SMB-0-10 mtor:
125 VDC 1900 RPM 0.72 Hp Valve Punction:
PCIC Turbina Steam Supply Calculated Maximrn Differential Pressure: Closed /1165 psi Open/1165 psi Minim m Required Stem Thrust Based on Differential Pressure, Piston Effect, and Packing Icad:
10718 lbs Maxima Available Stem Wrust Based on 80% Available Voltage:
11582 lbs Testing Performed and Basis:
Thrust signature testing was perfonred at static conditions to determine torque switch and limit switch actuations.
!;o flcw testing was performed because the required dp conditions could not be practicably achieved. We calculated maximum differential pressure is based on the reactor being isolated and maintained at pressure by the reactor relief valves operating on their opening setpoint. However, since F045 was identical to F022 in design, a comparison of f1cw test data and static test data for F022 was performed to determine FW operability.
As Found Conditions:
Torque switch settings of 2.0 and 2.125 were found which produced thrust trip points of 9.13 and 10.92 Klbs for the closed and open directions, respectively. The bypass for the open torque switch was set at 95% of the stroke time. We bypass for the closed torque switch was set at 1% of the stroke tim.
l Adjustments / Actions Performed:
Since the closed torque switch setpoint was less than the calculated minimum requirenent, the torque switch i
setting was adjusted to obtain more available thrust. During this effort, the torque switch was renoved and balanced.
We spring pack was removed for inspection and cleaning, and subsequently re-installed.
An as-left test l
yielded acceptable results. During the switch setting review prowss, it was l
determined that the closed torque switch bypass should be set at 95% of the l
closing stroke to ccrrply with instruction drawing ESK-2u for Cat I FN's with l
a closing safety function. Condition Peport 87-1143 was issued to evaluate this condition.
The Condition Report evaluation determined that operability could only be affected if the valve had internal damage that increased the closing thrust requirenent.
Operability was assured by STP-209-3302 which opened and closed F045 under rated steam pressure conditions and by a review of valve operating history that indicated no known operational failures. To be consistent with the River Bend design philosophy, Fbdification Request 87-0697 was issued to revise the control circuit so that the closed torque switch will be bypassed for 95% of the closing stroke.
As Inft conditions:
As-left torque switch settings of 2.0 and 2.5 produced thrust trip points of 11.48 and 10.31 K1bs for the closed and open directions, respectively.
17
Valve ID: E51*F045 Operability Evaluation: The MN was detennined operable. The following basis was used. F022 was closed and opened against full flow differential pressure of 1498 psi without torque switch actuation.
Using the conservative asstmption that the F022 torque switch would trip at the differential pressure of 1498 psi and the available differential pressure thrust margin of 11600 lbs as measured under static conditions, it was calculated that a differential pressure of 1165 psi for F045 would produce a maxinun differential pressure thrust requirenent of 9021 lbs (i.e. 1165/1498 psi X11600 lbs). This was based on the fact that F022 and F045 were identical in design.
As the F045 as-left data indicated, there was an available thrust of 9.18 K1bs in the torque switch trip point to acccmodate differential pressure requirements.
Since this available thrust was greater than the maxinun of 9021 lbs that may be required as validated by flow test data for F022, the as-left setpoints for F045 would ensure valve operability.
Although the as-found closed torque switch trip point was marginally less than the calculated mininun, a total thrust (i.e., including inertial thrust) of 14.10 Klbs was measured. his provided an available margin of 10.82 K1bs to close the valve against differential pressure conditions which could require as a maxinun, 9021 lbs of thrust as analyzed in the basis above.
In addition, the safety closing function that the valve performs is to shut dcwn the RCIC turbine, which would have been effectively accmplished even if it is assuned that valve did not close with total seal tightness. We open torque switch trip point is of no concern since it is bypassed for 95% of stroke time.
Adjustments that were made further enhanced valve performance by increasing the thrust margin and providing additional torque switch bypass time in the closed direction.
)
18
'IESTING MO OEERABILITY SG9RRY Valve ID: E51*F046 Type & Size:
2" 1500 lbs Velan Globe Opturw1. : Limitorque SMB-00-5 Motor:
125 VDC 1900 PIM 0.36 Hp Valve Function:
RCIC Inbe Oil Cooler Calculated Maxim = Differential Pressure: Closed /N/A Open/1386 psi Minin= Rtquired Stan Brust Based on Differential Pressure, Piston Effect, and Packing Ioad:
5078 lbs Maximana Available Stan % rust Based on 80% Available Voltage:
9690 lbs Testing Perfn-d and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow testing was performed because valve operation in the safety direction (i.e., open) is assured due to the torque switch bypass setting of 89%.
With the torque switch bypassed, the bOV can develop 12112 lbs of thrust at normal voltage and at least 9690 lbs of thrust under degraded voltage.
mis thrust capacity is significantly larger than the calculated minimum thrust requirement of 5078 lbs. Based on this conservative margin, flow testing at differential pressure conditions xmld not provide any significant additional assurance of valve operability.
As Found e nditions:
'Ibrque switch settings of 1.0 and 1.0 were found which produced thrust trip points of 5.21 and 6.63 K1bs for the closed and open directions, respectively. The bypass for the open torque switch was set at 89% of the stroke time. %e bypass for the closed torque switch was set at 9%
of the stroke tinn.
Adjustments / Actions Perfn-de None y
As Ieft Conditions:
Same as As Ebund Conditions Operability Evaluation:
We bOV was determined operable.
A cmparison of the torque switch trip points with the running load indicated a thrust margin of about 5 K1bs to close against the calculated differential pressure thrust requirment of 2694 lbs, and a thrust margin of 6.4 K1bs to open against l
differential pressure. The open torque switch bypass setting of 89% of stroke time further assures valve capability to open.
19
msrns Am wmmncrrr Sumer Valve ID: E51*F059 Type & Size:
4" 900 lbs Velan Gate Ci=ai.ur: Limitorque SMB-0-10 Motor:
125 VDC 1900 RFM 0.72 Hp Valve Function:
RCIC h st Peturn to the CST N1mlated Maxinaam Differeratial Pramarre:
Closed /1430 psi Open/N/A Minium Required Stan % rust Based on Differential Pressure, Piston Effect, and Padting Ioad:
9469 lbs Maxinem Available Stent % rust Haaad on 80% Available Vbltage:
9782 lbs Testirx1 Pernmnad and Basis:
A full flow testing differential pressure test was conducted in which the FOV was operated closed and open against a differential pressure of 1498 psi. h differential pressure produced by the test was consistent with the calculated maximtzn.
We minor variance was attributable to expected reading errors associated with analog gauges. trust signature testing was performed at static conditions to determine torgw switch and limit switch actuations.
As Pbund Conditions:
Torque switch settings of 2.0 and 2.0 were found which produced thrust trip points of 8.08 and 9.72 K1bs for the closed and open directions, respectively, h bypass for the closed te v e switch was set at greater than 90% of stroke time. We bypass of the open torque switch was set at 2.7%.
Adjustments /Acticms Perfonned None As Inft Conditions:
Same as As Found Conditions operabil.ity Evaluation:
The MOV was determined operable. The flow test verified that the measured thrust margin (trip point minus running load) was adequate to close the valve under design differential pressure conditions.
l l
20
'IESTING AE OPERARTT. TTY SE79RRY Valve ID: E51*F063 Type & Size:
8" 600 lbs Velan Gate GWe^ ic: Limitorque SMB-1-60 Motor:
480 VAC 3405 REN 7.8 Hp w
Valve Function:
RCIC Steam Supply Inboard Isolation calmlated Maxi== Differential Pressure: Closed /1165 psi Open/N/A Minin= Required Stan % rust Ramad on Differential Pressure, Pistm Effect, and Packing Ioad:
22092 lbs Mexinman Available Stan % rust Based on 80% Available Voltage:
26972 lbs
'ieshing Terfonned and Basia:
hrust signature testing was performed at static conditions.
Flow testing was not feasible in that the maxinun differential pressure of 1165 psi cannot be established. We calculated maxinum differential pressure is based on the reactor being isolated and maintained at pressure by the reactor relief valves operating on their opening setpoint, and a down stream break that results in near atnospheric pressure when the valve is nearly closed. This valve is normily open and is required to close only to isolate a design basis down stream line break.
As per the bulletin, valve testing under conditions simulating a break in the line containing the valve is not required.
As Found Conditions:
'IbIque switch settings of 1.5 and 1.5 were found which produced thrust trip points of 11.5 and 11.77 K1bs for the closed and open directions, respectively. Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Adjustments /Actims Pesie-i The torque switch settings were first increased to limiter plate values to increase the thrust margin.
Based on retest, it was determined that there was still inadequate thrust in the torque switch trip points. A new spring pack was installed based on input frm Limtorque. Acceptable test results kere obtained.
As Ieft Conditims:
As-left torque switch settings of 1.75 and 1.75 produced thrust trip points of 23.96 and 17.11 Klbs for the closed and open directions, respectively.
Operability Evaluation:
Although the as-found torque switch settings were within the range specified by Limitorque, the actuator did not produce the expected thrust trip points for the torque switch settings. Condition Report CR 88-0082 was issued to evaluate the thrust trip points found. At the time of condition discovery, the plant was shut down for refueling and the PCIC systm was inoperable and not required by 'Ibchnical Specifications.
During plant operation, the TV was operated successfully in tests performed under the ISI progrem. 'Ihe spring pack was rmoved for inspection and me?surments of the Belleville washers taken to verify that the proper spring pack was inatalled. No apparent physical damge was found, although it was apparent frm the test results that the spring pack had relaxed. A new spring pack was installed and the as-left test achieved satisfactory results.
21
'IESTING APO OPERABILITY SG9RRY Valve ID:
E51*F064 Type & Size:
8" 600 lbs Velan Gate Operator:
Limitorque SB-1-60 Petnr:
480 VAC 3405 RPM 7.8 Hp Valve Function:
RCIC Steam Supply Outboard Isolation almlated Maxismi Differstial Pressure: Closed /1165 psi Open/N/A Minin== Required Stm 2 rust Ram =1 on Differential Pressure, Piston Effect, and Packing Ioad:
22092 lbs Maxinaan Available Stm %Iust Ra==1 on 80% Available Voltage:
26972 lbs Testing Perfnrnwwl and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
Flow testing was not feasible in that the maximtrn differential pressure of 1165 psi cannot be established. We calculated maximum differential pressure is based on the reactor being isolated and maintained at pressure by the reactor relief valves operating on their opening setpoint, and a down stream break that results in near atmospheric pressure where the valve is nearly closed. mis valve is normily open and is required to close only to isolate a design basis down stream line break. As per the bulletin, valve testing under conditions simulating a break in the line containing the valve is not required.
As Pbund Cbnditions:
'Ibrque switch settings of 1.5 and 1.5 kere found which produced thrust trip points of 28.22 and 23.38 Klbs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke times.
,i Adjustments / Actions Perfouned:
None As Ieft Canditions:
Same as As Found Conditions operability Evaluaticn:
The FW was determined oper blo. The torque switch trip points provided more thrust than the calculated minimum requirement. The as-found closed torque switch trip point was evaluated with respect to the l
calculated mximum available thrust under degraded voltage. We evaluation indicated FM operability because the calculation assumd a stem factor that was based on a conservative coefficient of friction between the sta and sta nut. Using the torque c' data provided by Limitorque, the as-found 1.5 setting wuld give a tc trip point of 350 ft-lbs. Using this and the l
average measured trip point irust of 25.8 Klbs, a revised sta factor of l
0.0135 is calculated.
If this revised sts factor is used, the degraded l
voltage calculation muld yield a maximum available thrust of 31965 lbs.
In addition, the valve only has a safety function to close (i.e., steam line isolation in the event of a down stream break).
Under this scenario, the valve will not be required to open after it performed its safety function.
22 1
'IESTING APO OPERARTT TTY SG9RRY Valve ID: E51*F068 Type & Size:
12" 150 lbs Velan Cete Operator: Limitorque SMB-0-15 mer:
125 VDC 1900 RPM 1.8 Ep Valve Functim:
RCIC Turbine Steam Exhaust Isolation tw1mlated Maxi== Differential Pressure: Closed /8 psi Open/N/A Min 4== Ibquired Stm 'Ihrust Baaari cm Differential Pressure, Pistcm Effect, and Packing Ioad:
5825 lbs Max 4== Available Stm 'Ihrust Maaari m 83% Available Voltage:
10889 lbs Testing Perfnreart and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow was performed becauce of the expected low differential pressure and line pressure thrust requirment (735 lbs calculated).
As Found Cbnditions:
Torque switch settings of 3.0 and 3.0 were found which produced thrust trip points of 12.63 and 14.45 Klbs for the closed and open directions, respectively. Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Adjustments / Actions Performed:
None As Ieft Conditions:
Same as As Found Conditions Operability Evaluation:
The bW was determined operable. The torque switch trip points provided more than adequate thrust to close and open the valve.
%e as-found closed torque switch trip point was evaluated with respect to the o
calculated maximum available thrust under degraded voltage.
te evaluation indicated bm operability because the calculation asstrmd a stem factor that was based on a conservative coefficient of friction between the stem and the sta nut.
Using the torque output data provided by Limitorque, the as-found 3.0 torque switch setting smuld give a torque trip point of 173.5 ft-lbs.
Using this and the average measured trip point thrust of 13.54 K1bs, a revised stem factor of 0.0128 is calculated.
If this revised stm factor is used, the degraded voltage calculation would yield a maximum available thrust of 13195 lbs.
23
'IESTING AE OPERAR1TJTY StMERY Valve ID: E510F076 Type & Size:
0.75" 1500 lbs Velan Globe Cr - &L.u.: Limitorque SMB-000-2 mtor 460 VAC 1700 RPM 0.115 Hp ri Valve Functicm:
RCIC Steam Line Warming Valve calculated Maxinan Differential Pressure: Closed /1105 psi Open/N/A Mininne Required Stm Wrust Raaad on Differential Pressure, Piston Effect, and Packing Ioad:
2393 lbs Maxinaam Available St m % rust Based on 80% Available vbltage:
3636 lbs Testing Perfnnmad and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow testing was performed because of the expected low thrust requirement due to the small valve orifice area. The calculated differential pressure thrust requirement of 393 lbs accounts for 16% of calculated total thrust requirement.
As Pbund Cbnditicms:
Torque switch settings of 3.5 and 3.0 were found for the closed and open directions, respectively.
Signature testing yielded inconclusive results regarding torque switch thrust trip points.
Corrective actions were taken as described below. Satisfactory retest data was obtained (see As Ieft Conditions).
Adjustments / Actions Perfnmad:
We operator was disassabled to access the torque switch and spring pack. he torque switch and the spring pack were rmoved and inspected. Degradation of the torque switch contacts was noted, and the torque switch was replaced.
Because the mv was located in a radiation area very difficult to access (in the drywell), it was decided that additional maintenance should be performed while the operator was already disassabled. As an added measure to assure valve operability, the spring pack, limit switch ass m bly, and the actuator internals were replaced.
As Ieft Conditicms:
As-left torque switch settings of 3.5 and 3.0 produced thrust trip points of 3.65 and 3.87 Klbs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Operability Evaluation:
he mV was determined operable.
This evaluation was based on the satisfactory LLRT that was performed prior to the signature testing. The mV was electrically operated closed and the LLRT performed.
Satisfactory LLRT results indicated the valve was able to close satisfactorily against at least 84% of the total thrust requirments prior to the signature test.
As-left data indicated nore than adequate thrust in the trip points to close and open the valve.
24
'IESTING AE TEIRBILITY SD9RRY Valve ID: E51*F077 Type & Size:
1.5" 600 lbs Velan Globe Optu d' u.:
Limitorque 94B-000-2 Motor:
480 VAC 1700 RPM 0.125 Hp
- u Valve Functicn:
Vaccum Breaker Valve t'almlated Maxi== Differential lhas=2re: Closed /23 psi Open/N/A Mini== Required Stem 'Ihrust Based cn Differatial Pressure, Piston Effect, and Packing Ioad:
2413 lbs Maxi =m Available Staa 'Ihrust Based on 80% Available Voltage:
3200 lbs
'Desting Performed and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow testing was performed because of expected low differential pressure thrust requirment of 28 lbs.
As Fr.und Cbnditions:
'Ibrque switch settings of 1.25 and 1.25 were found which produced thrust trip points of 3.92 and 3.13 K1bs for the closed and open directions, respectively.
Both torque switch bypasses were set at greater than 90% of their respective stroke times.
Adjustments /Acticms ruimed:
None As Inft Otniiticms:
Same as As Found Conditions operability Evaluation:
'Ihe hW was determined operable. The torque switch trip points provided nore than adequate thrust to close and op2n the valve.
Because a spring pack preload of 1.25Klbs was measured, the closed torque switch trip point of 3.92 Klbs represented available thrust to operate against i
the calculated differential pressure thrust requirement of 28 lbs. 'Ihe closed torque switch trip point was evaluated with respect to the calculated available thrust under degraded voltage.
'Ihe evaluation indicated FW operability because the calculation assurted a conservative coefficient of friction between the sta and the stem nut. Using the torque output data provided by Limitorque, the as-found 1.25 setting wuld give a torque trip point of 25.5 ft-lb.
Using this and the reasured trip point thrust of 3.92 K1bs, a revised stm factor of 0.0065 is calculated.
If this revised stm factor is used, the degraded voltage calculation muld yield a maximum available thrust of 4923 lbs.
25
'IESTING MO OPERABILITY S[M4ME Valve ID: E51*F078 Type t Size:
2.5" 600 lbs Velan Globe Operator: Limitorque SMB-000-2 mtor:
480 VAC 1700 RPM 0.125 Hp Valve Functim:
Vacuum Breaker Valve Calculated Mariam Differential Pressure: Closed /23 psi Open/N/A Minime Requirs! Stan 'Ihrust Raami on Differential Pressure, Pistrm Effect, and Packing Ioad:
1707 lbs Maxim m Ayn11ahle Sten % rust Raami on 80% Avn11ahle Vbitage:
3364 lbs Testing Pers--- i and Basis:
Thrust signature testing was performed at static conditions to determine torque switch and limit switch actuations.
No flow testing was performed because of the expected low differential pressure thrust requirement of 125 lbs which accounts for 7% of the total thrust requirement.
As Fcond Canditim s:
Torque switch settings of 2.0 and 2.0 were found which produced thrust trip points of 1.71 Klbs and 950 lbs for the closed and open directions, respectively.
The open torque switch bypass was set at greater than 90% of stroke time. %e closed torque switch bypass was set at 71% of stroke time. 1.26 Klbs of backseating was observed.
Adjustments /Actims Perfnr=w1:
The open limit switch was adjusted to eliminate backseating.
We red indication light contact (rotor 3) was adjusted frm 76% to about 95% of full closed.
As Ieft conditions:
The torque switch settings and thrust trip points, and the bypasses here the same as As Found.
We backseating condition was eliminated.
Operability Evaluatim The br# was detexmined operable. 'Ibrque switch trip points provided for nore than adequate thrust to close and open the valve.
Since a spring pack preload of 660 lbs was measured, the closed torque switch trip point of 1.71 Klbs represented available thrust to close the valve against the calculated differential pressure thrust requirment of 125 lbs.
We closed torque switch bypass setting of 71% of stroke time did not affect operability because the valve was stroked closed satisfactorily, indicating that the torque switch was rrore than adequate to operate against the packing load which was below the spring pack preload.
Since the packing load represents 93% of the total calculated load, the valve would easily close against the differential pressure thrust requirement even with the bypass set at 71%. We adjustments that were trade further enhanced FDV perfontance by eliminating the backseating.
26
O APPD OIX B
'IEErr PROGRAM 'IO GMNS' IRA'IE VALVE TERMIILI'IY
APPDOIX B TEST PROGRAM 70 DDONSTRATE VALVE OPERABILITY FOV ID SIZE /TY_PE ME7 HOD CONENTS E22*F001 16" GTE FULL FIN SIGNAWRE TEST COLLE:T DYNAMIC SIGRWRE DATA E22*F004 10" GIE HYDROSTATIC dP SIGRWRE COLLECT SIGNAWRE DURING TEST TEST E22*FV10 10" GLB FULL FIN SIGR7URE TEST COLTJET DYNAMIC SIGRWRE DATA E22*F011 10" GLB STATIC SIGRWRE TEST IDD7fICAL TO E22*F010, SET TORQUE SWI'IU{ BASED UPON E22*F010 FIN TEST DATA E22*F012 4" GTE FULL FIN SIGRWRE TEST 00LUrr DYNAMIC SIGRWRE DATA E22*F015 20" GIE HYDROSTATIC dP SIGRWRE COLLECT SIGRWRE DURING TEST TEST E22*F023 10" GLB STATIC SIGR7URE TEST IDENTICAL TO E22*F010, SET TORQUE SWI70i BASE UPON E22*F010 FIN TEST DATA E51*C002 4" GLB NO TEST REQUIRW SPRING CIN URE-FOR SAFETY E51*F010 6" GTE STATIC SIGRWRE TFST DGIhTERING ANALYSIS BASE ON IN THRUST CONTPIBUTICN DUE TO DIFFEREtfrIAL PRESSURE E51*F013 6" GTE FULL FT4W TEST WITH COLLECT SIGO.WRE DATA DURING AMPS M O HYDROSTATIC dP TEST TEST E51*F019 2" GLB FULL FTG TEST WITH AVPS REVID1 CURRENT DATA TAKDi DURING FUIL FT G TEST E51*F022 4" GLD EF.', F72 TEST WITH JWPS REVIEW CURRENT DATA TAKDi DURING FULL Fim TEST E51*F031 6" GrE STATIC SIGRTURE TEST hNGINEERINGANALYSISBASECN Im THRUST CGmummCu DuE TO DIFFEPINTIAL PRESSIR' E51*F045 4" GLB STATIC SIGRWRE TEST IDD7TICAL 70 E51*F022, BUT STEAM E7 m VS WATER 1
APPENDIX B TEST PROGRAM 'IO DDONSTPATE VALVE OPERABILITY MJV ID SIZE / TYPE MEmn CO MENTS E51*F046 2" GLB STATIC SIGRWRE TEST ENGINEERING ANALYSIS - GLOBE VALVE WTIE PRESSURE UNDER 'IEE SEAT AND SAETIY REIATED 'IO OPEN ONLY E51*F059 4" GTE FULL FIN TEST WTIH AMPS RLVIEW CURRENT DATA TAKEN DURING FT.1LL FIN TEST E51*F063 8" GTE STATIC SIGRWRE TEST STEAM ISOLATICH VALVE-BULILTIN DOES NOT REQUIRE TESTING 'IO SIMUIATE A LINE BREAK E51*F064 8" GIE STATIC SIGRWRE TEST STEAM ISOIATICH VALVE-BULILTIN DOES NOT RDQUIRE TESTING 'IO SDUIATE A LINE BREAK m
E51*F068 12" GTE STATIC SIGRWRE EST ENGINEERING ANALYSIS BASED CN IN 'IERUST CONTRIBUTICN DLE 'IO DIFFERENTIAL PRESSURE E51*F076
.75" GLB STATIC SIGRWRE 'IEST STEAM LINE WABMING-BULIETIN DOES NOT RB2UIRE TESTING 'IO SDUIATE A LINE BREAK E51*F077 1.5" GLB STATIC SIGRWRE TEST ENGINEERING ANALYSIS BASED CN 1M 'IERUST CONTRIBUTICN DUE 'IO DIFFERENTIAL PRESSURE i
E51*F078 2.5" GLB STATIC SIGNAWRE TEST ENGINEN ANALYSIS BASED CN IN 'IERUST CCNIRIBUTIGI DLT 'IO DIFFEFENTIAL PRFESURE 1
2
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APPD OIX C SIGNMURf!l 1ESTDG USING TfE OMTS PDV SYSIIM I
1.0 Signature % sting Methodology Impell's OATIS MOV system (Operations Analysis and h sting Interpretive Systs) was utilized to test (i.e., collect data for) the GSU bulletin M 's.
The system's basic function was to measure / calculate sts load developed by the mtor operator and setpoints associated with controlling the operation of the M.
1.1 General The specific design of the Limitorque operators allows the calculation of sts loads by measurement of spring pack novment within the motor operator.
By measuring valve sta loading and spring pack nov ment simultaneously, a correlation of the two parameters is established.
he correlation is applied to the spring pack novment data obtained during valve operation to derive a sts thrust versus stroke time profile, mtor current, and limit and torque switch operation data are also obtained during valve operation to determine the notor current profile and the times at which the switches are actuated. We sensors used for obtaining the aformentioned data are: 1) a load cell that is mounted on top of the valve operator housing; 2) a linear displacment probe that is nounted on the spring pack cap or capcover; 3) an amp probe that is clanped around the notor lead; and 4) test leads that are clipped to the geared limit switch contacts and connected to RF sensors that are clanped around the torque switch wires.
1.2 Principles of M Operation he Q\\ TIS M systs is based on the specific desigi of Limitorque SMB/SB operators.
We following describes their typical operation.
Refer to Figure 1
for illustration.
The electric motor has a helical pinion mounted on its shaft extension.
%is pinion drives the wm shaft clutch gear which is engaged with the korTn shaft clutch.
his piece is splined to the wom shaft. he kom is l
splined to the wom shaft and when it is rotated, it turns the kom gear. %e kom gear has two lugs cast onto the top portion which engages the two lugs on the drive sleeve.
Wese lugs are spaced so that when the kom gear begins to turn during notor operation, there is a certain anount of lost notion before the lugs engage and cause the hanner blow effect within the operator.
d 1
4 As soon as the wom gear lugs engage, the drive sleeve being splined internally with the stem nut, causes the stem nut to rotate and open or close the threaded sta of the valve.
We stm nut is threaded to fit the thread of any rising stem velve.
%e sequence of typical gate valve closing is as follows:
he m tor transmits rotary torg.ie through the helical gearing and then through the second reduction worm and worm gear.
The worm gear drives the sta nttt.,,
Botation a threaded nut creates linear notion of the valve stem and resultant valve movment.
When the valve closes, the dice la pressed "into the valve seat, thus seating ~the valve.
Since the valve is seated, the disc no longer can move in a dovuard direction. However, the motor drive still continue's to rotate ury3er increased load conditions.
Instead of the worm gear continuing-to rotate, the worm actually threads itself along the worm gear as
~
the,sprjng pack is empressed. The wrm rides ' on a precision spline which permits this axial mvement.
Movment of the wom trips the torque switch which breaks the electrical mtor circuit. The mechanical self-locking feature, inherent to the worm gear dasign, maintains valve seating force and assures a i
tight valve until the E V is energized in the "Open" direction.
1.3 OATIS mv Testing and Analysis Details Stm Ioad Data Stem load calculations require that a parameter directly relating to stcm load be monitored for the entire valve stroke.
We parameter is the spring pack movment.
Because of the Limitorque design, the mvment of the kom is proportional to the load being delivered to the valve stem. OATIS E V utilizes a LVDT to monitor this movment.
1b correlate stem load to spring pack mveent, a method to measure actual stem load is required. CATIS M V utilizes a ec Tpression load cell against which the valve 2
is electrically operated in the open direction during the spring pack calibration stroke. As the valve sta impacts the load cell, load data and spring pack novment data are collected. We measured load and the spring pack displacment data are evaluated to establish the stm load / spring pack correlation.
Motor Current Data Mor.or current is measured for the valve stroke to provide secondary indication of MOV mechanical load condition. No thrust calculations are based on measured notor current.
We motor current signature also provides indications of motor performnce, and contactor drop out tim information, etc.
Svitch Operation Data Switch actuations are detected to provide infonraticn regarding proper settings, trip times, and switch functionability.
Geared limit switches pluviding the torque switch bypass functions and position limit functions are nonitored to determine actuation times relative to stroke time. We torque switch is monitored to determine trip times which are correlated to sts thruct.
Data Acquisition Data is autcrnatically obtained for the above parameters concurrently during any one stroke f1.0.
all data relating to the open stroke is captured during the stroke). We same applies to the closed stroke, and the spring pack calibration stroke.
A minimum of 4000 points per parameter is captured during any one of the o
above three strokes.
Data obtained by the OATIS MOV sensors are processed to achieve specific characteristics necessary for inpat to the ccr puter. The signal conditioning process includes excitation for passive sensors, signal anplification and ranging, and analog to digital conversion to reake the output frcrn the sensors ccrnpatible with the readout device (i.e. ccr:puter).
We mtputer and specially developed software are used to 1) control data acquisition, 2) store the acquired
- data, 3) assist the user in data evaluation, 4) calculate critical parameters, and 5) provide graphic (signatures) and written reports of the acquired and analyzed data.
3
A Data Analysis Data is converted into engineering units and can be riisplayed on graphs (signatures).
Calculations are performed to:
Correlate spring pack displacanent data to measured stem load via a second order polyncmial curve fit.
Convert spring pack displacenent data frun the valve strokes into stem load.
Determine critical MOV parameters relating to sten thrust, geared limit switch, and torque switch setpoints.
4 i
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L Valve Sten Helical Pinion Upper Bearing Gear Thrust Cover Bolts Wom Drive Wom Gear Lugs Gear Sleeve
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F~~,.
W
,1 3
q Q
<t
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t e
y
.f
~.
i Worm Shaft t
s.
Clutch Gear 2
Wom Shaft 6
h Clutch O
Li. wit Switch Drive Gear Torque Sp ing Switch Pack Spring Pack Cap Wom Drive and Dust Cover Shaft WO" CUTAWAY VIEW OF SMB-0 LIMITORQUE MLVE CONTROL X7 m
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