ML17264A375
| ML17264A375 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 02/16/1996 |
| From: | Mecredy R ROCHESTER GAS & ELECTRIC CORP. |
| To: | Andrea Johnson NRC (Affiliation Not Assigned), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-95-07, GL-95-7, NUDOCS 9602260084 | |
| Download: ML17264A375 (19) | |
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CATEGORY 1
REGULAT(
INFORMATION DISTRIBUTION STEM (RIDS)
ACCESc)ION NBRe 9602260084 DOC ~ DATE+ 96/02/16 NOTARIZEDo YES DOCKET I FACIL':50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G
05000244
,AUTH.NAME AUTHOR AFFILIATION MECREDY,R.C.
Rochester Gas a Electric Corp.
RECIP.NAME RECIPIENT AFFiLIATION JOHNSONPA.R.
SUBJECT:
Submits response to GL 95-07, "Pressure Locking 6 Thermal Binding of Safety-Related Power-Operated Gate Valves."
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TITLE: Generic Ltr 95-07 Pressure Locking a Thermal Binding of Safety Rela T NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72).
05000244 E
RECIPIENT ID CODE/NAME NRR/DRPE/EATON JOHNSON,A INTERNA
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ROCHESTER GASANDE1ECTRIC CORPORAT1ON e 89 EASTAVENUE, ROCHESTER, N. Y 1dbf9-M01 AREA CODE716 5d'6-2700 ROBERT C. MECREDY Vice President Nudear Operations February 16, 1996 U.S. Nuclear Regulatory Commission Document Control Desk Attn:
Allen R. Johnson Project Directorate I-1 Washington, D.C.
20555
Subject:
180 Day Response to NRC Generic Letter 95-07 R.
E. Ginna Nuclear Power Plant Docket No. 50-244 Ref.(a):
Westinghouse Owners Group Correspondence WOG-95-320, Valve Categorization Criteria for Pressure Locking Thermal Binding (PL/TB)
(MUHP-6050), dated 10/19/95
Dear Mr. Johnson:
In accordance with the reporting requirements delineated by NRC Generic Letter (GL) 95-07, Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves, this letter represents Rochester Gas
& Electric (RG&E) Corporation's 180 day response to the information requested by GL 95-07.
GL 95-07 was issued to request that licensees perform appropriate evaluations of power-operated gate valves with regard to their susceptibility to the phenomena identified as pressure locking and thermal binding.
Within 90 days, each licensee was requested to identify the valves which were found to be potentially susceptible to pressure locking and/or thermal binding and provide acceptable bases for their operability or take appropriate action.
Within 180 days, each licensee was requested to evaluate the potentially susceptible valves and perform further analysis, and any needed corrective actions, to ensure that identified potentially susceptible valves are capable of performing their current licensing basis safety functions.
The categorization criteria developed by the Westinghouse Owners Group (WOG), shown above as Reference (a),
has been utilized to facilitate the performance of the attached evaluations.
The format of Attachments 1 and 2 follow these guidelines.
In accordance with GL 95-07, the following is submitted:
1.
The operational configurations of safety-related power-operated gate valves have been evaluated for the purpose of identifying potential susceptibility to pressure locking and/or thermal binding.
Results are enclosed as Attachment 1 ~
9602260084 9602ih PDR
" ADQCK 05000244I
'JC4~
trt 820 I</1>g
E 1
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1". Pi i
2 ~
Further analyses to ensure that the identified potentially susceptible valves are capable of performing their intended safety functions under all modes of plant operation, including test configurations, are enclosed as Attachments 2
and 3.
Attachment 3 includes justification for potentially susceptible valves identified in Attachment 2 to remain in their current configuration.
Very truly yours, Robert C. Mecredy KAM'tt418 Subscribed and sworn to before me o
this 16th day of
- ebruary, 1996.
I
(
Notary Pu lic DEBQRAH A.PIPERNI Notary Public m the State of New York ONTARIO COUNTY Commission Expires Nov. 23, 19'g7 xc:
Mr. Allen R. Johnson (Mail Stop 14B2)
Project. Directorate I-1 Washington, D.C.
20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 US NRC Ginna Senior Resident Inspector
Attachment 1
WOG POWERS)PERATED VALVEPL/TB SCREENING FOR GIMNA VALVE DESCRIPTION ACT.
TYPE GATE TYPE NORMAL POSnON
- 2. FUNCTION gf either answer b NO, vdve b non suscepblrb) 3.COMPONENT DEQGN FOR PRESSURE LOCK gf YES, valve is not susceptible to PL)
- 4. COMPONENT DEQGN FOR THERMALBIND gl YES, vahre b not
~capt'ble to TB)
Open Sdety Ftstction)
Ever dosed during norm or abnonn operation)
Sa5d Wedge)
Double or Pwaibl Disc Gato7 Valve Susceptibb to Pfesstxc Locking7 Valve Susceptibb to Themal Binding) 738A/8 749A/8 Comp Ccogng Water Comp Cooling Water CCW to RHR Heat Exchanger CCWto RCPs MOV SCUD MOV FLEX CLOSED OPEN YES HO YES HIA YES NIA NIA NO NIA NIA 769A/8 813/814 817 313 8 BOA/6/C/D 898 A/8 3604 P/3 60 6A Camp CooEng Water Comp Caoling Water Comp Cooling Water Chem/Vd Contrd Containment Spray Containment Spray Main Steam CCW from RCPs CCW ta Reactor Support Coolers CCW to Cont oinmcnt Seal or Excess Letdown Rensn Containment Spray PNnp Dbchwge RWST to CS and S Pumps Main Steam to TDAFWPump MOV FLEX MOV FLEX MOV FLEX MOV DOUBLE MOV DOVBLE MOV DOUBLE MOV FLEX OPEN OPEN OPEN OPEN CLOSED OPEN CLOSED NO NO YES NO YES NIA MIA NIA NIA YES HIA YES NIA NIA NIA MIA NO NIA NO NIA NIA NIA NIA YES NIA HO NIA NIA NIA NIA YES HIA YES NIA NIA NIA HIA HO HIA YES 616/618 704 A/8 860A/8 862A/8 868 1813A/8 841/886 867A/8/C 871A/8 1816A/8 9748 Rcsid Heat Removal Resid Heat Removal Resid Heat Removal Resid He>> Removal Resid Heat Removal Safety In)sedan Safety In)codon Safety Injccdon Safety Injection PORV Block Valves RHR Pump Suction RHR Pump Suction from Canto@ment Saanp RHR to Reactor Vessel Deluge RHR Pump Suction from RWST RCDT Pump Sucuan from Cantalnment Sump Q Accurrxfotor Dbcharge RHR Pump Discharge to Q Pumps S Pump C Discharge Q Pump C Suction SAFW Pump D Emergency Dbchorge MOV DOVBLE MOV DOUBLE MOV DOUBLE MOV FLEX MOV DOUBLE MOV DOUBLE MOV DOUBLE MOV DOUBLE MOV FLEX MOV DOUBLE MOV FLEX OPEN OPEN CLOSED CLOSED OPEN CLOSED OPEN CLOSED OPEN OPEN OPEN YES YES YES YES MO HO YES YES YES YES HO YES YES YES YES MIA HIA NO YES YES YES MIA NO NO NO NIA HIA NIA NO NO NO NIA YES YES YES NIA NIA NIA YES NO YES NIA YES YES YES YES NIA NIA NIA YES YES YES NIA NO NO YES NIA NIA NIA YES NO M/A 4616/4818 4683 4864 Service Water Service Water Scnrice Water Auxigary BtaMing SW lsd ation SW to AirCorxfidaning Coolers SW to Turbine Bulding MOV FLEX MOV FLEX MOV FLEX OPEN OPEN OPEN YES NO NO YES NIA HIA HO NIA NIA MO NIA NIA YES NIA NIA YES NIA NIA 487O Senrice Water SW to Ttxbina Bulding MOV FLEX OPEN MO HIA NIA MIA MIA NIA
0 0
1
Attachment 2
WOG SYSTEM LEVEL SCREENING FOR Pt/TB SUSCEPTIBLE VALVES FOR GINNA Valve 7A.PRESSURE LOCKING-HYDRAUUC EFFECT 7B.PRESSURE LOCKING.THERMAL EFFECTS BA.THERMALBIHDiNG-WEDGE EFFECT BB.THERM BINDIHG-STEM EFFECT COMP.
LEVEL SCREENING Dedgn Feature that mitigates PfeSSVC fockf Exposed to high pressve fluid and N PIPhlg potcf¹i4gy dcpressvizcd pflor 'to
~ctuation)
Not normally cxposcd to hgh pressve ffdd but potentially 4xposod 'to high pressvo fiuid due to fcafvge and potendaffy depressurftcd pflofto actuationf ls valve susceptible to PL due to Hydrauyic Effectsf Valve st<<n at or bdow horltant at 7 Body temp.
increase due to fluid in attached piping7 Body temp.
increase due to external sovcorf Body tcinp.
increase gf4atef than nornlal ambient swings7 ls va/vo susceptible to PL due to Thermal Effectsf is valve dosed hot followed by sigdfic<<¹ coofdown
~nd then lequi ed to opcnf ls hot valve reqdred to dose whTC
~ystem/valve
<<4 cooling down snd than reqdred to open after cooledf Can ~
<<grificant tefnp<<atv4 gf<<fieflt develop
~cross the valv4 aftsf it fs dosed and than the valve is roqiafod to open7 ls valve suscept to TB due to Wedge Effect 7 ls valve closed hot with rle af'ter cooling arid than roqvfod to opcnf ls the vahie reqdred to dose whle the system
<<xl valve are cooling down ard then signaled to op4n before c<<n plctely cooled down7 is vahre sue ccpt to TB due to Stem Effect7 73SA/8 NIA HIA NIA HIA NIA NIA NIA NIA NIA NO NO NO NO NO NO NO 8 60A/8 IC/D 3604A 3606A NO NO YES NO YES NO HO NO NO NO NO YES NO YES NO YES NIA NO NIA HO NIA NO NIA NO NIA YES NIA NO NIA YES 616 618 YES HIA NIA NIA HIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA 704A/8 NO NO HO NO NO NIA NIA NIA N/A NIA NIA NIA 860 A/8 862A/8 867A/8 IC YES NO NO NIA YES NIA YES NO NIA YES YES HIA HO NO NIA NO NO NIA YES HO HIA YES NO NIA YES NO NIA NO NIA NIA NIA NIA NIA NIA NO N/A NIA NO HIA NIA NO NIA NIA NO NIA 87 1 A/8 YES NO YES NO NO HO NO NO NO NO HO NO NO NO NO 1816A 18168 NO NO NO NO NO NO NIA NIA NIA NIA NIA NIA NIA 4816 4818 NO NO NO NO NO HO NO NO NO NO NO
Attachment 3
This attachment shall summarize the bases for justification for continued operability for the power-operated gate valves identified as potentially susceptible to pressure locking and/or thermal binding including any assumptions.
The criteria developed by the WOG has been employed in the preparation of this evaluation summary.
738Ag 738B These motor-operated gate valves have solid wedge discs and are therefore not susceptible to pressure locking.
These valves are normally-closed component cooling water supply valves to the RHR heat exchangers.
These valves are not subject to significant temperature changes and are not "hot" when in operation.
Component cooling water to the RHR heat exchanger is typically less than 1004F resulting in no significant temperature gradients.
There are no potential steam sources that could produce high ambient temperature.
Therefore, these valves are not susceptible to thermal binding.
860Aq 860Bq 860Cq 860D; These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
These valve serve as the discharge isolation for the containment spray pumps.
The need has been postulated to re-open these valves during the sump recirculation phase.
This would require opening the valves prior to spray pump start.
Conservatively assuming that the valve bonnet is trapped with the spray pump shutoff head plus RWST static head
( 282.9 psig) and conservatively assuming that the downstream spray piping drains down via the leaking parallel spray valve the calculated thrust to overcome this pressure differential is 4758 lbs.
(Enclosure 1).
The minimum available thrust under degraded voltage conditions is 5901 lbs.
Therefore, these valves are not.
susceptible to pressure locking.
Page 1
of 5
4 I
1
3504Ai 3505A These motor-operated gate valves have flexible wedge discs and serve to provide main steam to the turbine-driven auxiliary feedwater pump.
These valves are maintained closed and are required to open to supply steam to the turbine.
These valves are located at the peak of a riser in the horizontal position with the valve stem pointing upwards thus minimizing the possibility of condensed liquid collecting in the bonnet.
If rapid depressurization were to occur, the affected steam line would be considered faulted and there would be no need to open the valve.
The valves are maintained "hot" since they isolate the main steam header and are relatively close to it.
Therefore, these valves are not susceptible to pressure locking.
These valves may be closed after opening and then re-opened,
- however, no significant cooling down of the valve or system would occur if the valves were'xpected to be needed to be re-opened.
This would occur to balance steam loads and no problems have been experienced in the past.
The building temperature may reach 212'F due to high energy line break,
- however, due to the valves close proximity to the unfaulted steam line, no significant temperature gradient would occur.
Therefore, these valves are not susceptible to thermal binding.
515@
516 These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
These valves serve as block valves for the pressurizer power-operated relief valves; These valves were modified in 1989 with upstream discs that have vent holes to equalize pressure
- and, therefore, these valves are not susceptible to pressure locking.
704Ai 704B These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
These normally-open valves serve as suction isolation for the RHR pumps.
These valves are in the Auxiliary Building sub-basement and are isolated from external significant heat sources.
These valves are not exposed to high pressure fluid nor are they subject to rapid depressurization, therefore, these valves are not susceptible to pressure locking.
Page 2
of 5
850Aq 850B These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
These normally-closed valves serve as RHR pump suction valves from the containment sump.
These valves were subjected to a pressure locking event in 1969 and have since been modified, in 1970, to include bonnet vents to the RHR pump suction side of the valve.
Therefore, these valves are no longer susceptible to pressure locking.
852Ai 852B These normally-closed, motor-operated gate valves have flex wedge discs and serve as RHR supply to the reactor vessel deluge.
These valves have been evaluated as being susceptible to both pressure locking and thermal binding.
Analyses of these conditions have been performed and the valves have been found to possess sufficient thrust margin to overcome the calculated effects due to PL/TB.
These analyses have been reviewed by NRC MOV Program Inspection Teams and, with minor comments, have generally found to be acceptable.
Therefore, these valves are not susceptible to pressure locking and/or thermal binding.
857Aq 857Bq 857C These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
I These normally-closed valves serve as RHR pump discharge to the SI pumps.
These valves could experience backleakage from the RCS during the post LOCA injection phase which could pressurize the RHR system to a conservatively estimated 614.7 psig.
In response to this condition, plant operating procedures specify instructions for venting the piping.
This activity vents the piping but not the valve bonnets.
Using conservative pressure
- values, the required thrust to unseat the valves is calculated to be 8840 lbs.
(Enclosure 2).
The limiting available thrust at this time is 9027 lbs.
Therefore, these valves are not susceptible to pressure locking.
Page 3
of 5
871Ai 871B These normally-open, motor-operated gate valves have flex wedge discs and serve as discharge valves for SI Pump C.
During the injection phase, these valves are not subject to significant temperature changes and are not "hot" when in operation since injection water is supplied from the RWST.
During the recirculation phase, SI pump discharge temperature is less than 2004F and gradually decreasing resulting in no significant temperature swings.
These valves would not be closed "hot", allowed to cool and then re-opened.
There are no potential steam sources that could produce high ambient temperature.
Therefore, these valves are not susceptible to thermal binding.
A scenario has been identified where one of these valves may be closed and then require re-opening while SI Pump C is stopped.
The effects of pressure locking may cause resistance to re-opening unless SI Pump C is restarted.
However, the conservatively calculated thrust to overcome pressure locking forces is 4735 lbs. which is much less than the available thrust (Enclosure 3).
Therefore, these valves are not susceptible to pressure locking.
1815Ag 1815B These motor-operated gate valves have double discs
- and, therefore, are not susceptible to thermal binding.
These valves serve as suction to SI Pump C from the RWST.
The only pressure available to these valves is the static head from the RWST, therefore, these valves are not susceptible to pressure locking.
4615'616 These normally-open, motor-operated gate valves have flex wedge discs and serve as the service water isolation for safety-related loads in the Auxiliary Building.
These valves would close and then re-open upon SI actuation.
These valves are not subject to significant temperature changes and are not "hot" when in operation.
Service water to the Auxiliary Building is always less than 90'F resulting in no significant temperature gradients.
There are no potential steam sources that could produce high ambient temperature.
Therefore, these valves are not susceptible to thermal binding.
Page 4
of 5
Rapid depressurization of adjacent piping is possible,
- however, if this were to occur, there would probably not be a need to open the affected valve.
Additionally, system pressure is relatively low (less than 70 psig),
and the GL 89-10 MOV Program ensures operation against a differential pressure of 95 psid.
Therefore, sufficient operability margin exists to ensure safety function performance, and these valves are not susceptible to pressure locking.
Page 5
of 5
" "'""'blationSheet Date: I~'/'f Sheet:~2.
Chk:
Date: 'lt I
Rev. No.: 0 I))ttachment 3,
8 Gale. No.: 94108-C-1 By: Steve Greer 3.2.3 VALVE860 A Ec B>C,D(6x4x6 300 ¹ Anchor/Darling DD gate)
Calculate the value of thrust required to liftthe valve 860 A,B,C 8 D offits seat during the limiting pressure differential specified in section 3.1.3. See ref. 5.10 for design input Disc Mean Seat Diameter" Stem Diameter Bonnet Pressure Pressure Upstream (pump side)
Pressure Downstream(Rx side)
Stem/disc Weight" D p '= 4.5 in D S
.'= 1.375 in P B
'.= 282.8 psi P US '3'6 P pS:= 37. psl F WIbf Stem Factor Packing Friction Load Disc Seat Angle Friction Coefficient Closing Thrust-
"Assumed value FS:=.0151 ft F PF:= 1000 Ibf
):= 00 deg C '4000 Ibf Stem Area:
)i D S AS:=
4 AS=1.48 in2 nDp DiscArea: Ap'.=
4 A p =15.9
~in
~ 2 Stem Differential Pressure Load:
F stem:= P B AS F stem = 420 ~Ibf Disc Differential Pressure Load:
( '
US P DS) II A D FDP:
cos()) + Ii sin())
F pp = 3936
~Ibf Sealing Load:
(T D P pp) (S ccs()) s)n()))
F seal 'in()) + Ii cos(())
F seal = 13000'Ibf USE F
I '
'Ibf from ATI. C MOVtest
=Tbtque Reaction Factor:
TRF:=
Dp TRF = 0.96 FW+ F PF F stem+ F DP+
seal T'-
TRF EQ (1)
Required Thrust T = 4758
~Ibf Limitingavailable thrust from MOVtesting equals 9027 Ibf. for weaklink and 1101 6 for motor stall (see attch. C) which is sufficient to overcome the required thrust.
.ttachnent 3, Fnclosare 2
~
~
Gale. No.: 94108-C-1 By: Steve Greer Rev. No.: 0 Chk:
Ca Ulation Sheet Date: ~/'~ Sheet: 2-0 Date: ~II I 'F(
3.2.2 VALVE857 A, B sr, C(6x4x6300¹Anchor/Darling DD gate)
Calculate the value of thrust required to liftthe valve 857 A,B 8 C offits seat during the limiting pressure differential specified in section 3.1.2. See ref. 5.10 for design input.
Disc Mean Seat Diameter-Stem Diameter Bonnet Pressure Pressure Upstream (pump side)
Pressure Downstream(Rx side)
Stem/disc Weight" D D
.'= 4.25 in D S
'.= 1.375 in P B
.'= 614.7 psi P US
'.= 147. psi P DS
'.= 2.9 psi F W'0ibf Stem Factor Packing Friction Load Disc Seat Angle Fiiction Coefficient Closing Thrust "
"Assumed value FS:=.0151 ft F PF:= 1000 Ibf
):= 0 deg T C '4000'Ibf DS~
Stem Area:
A S '.=
4 A S = 1.48 ~in
~ 2 i(DD DiscArea: A D'.=
4 AD = 14.19
~in Stem Differential Pressure Load:
stem
"stem =9 Disc Differential Pressure Load:
('
PUS PDS)'F'AD FDP cos(4) + Ii sin())
F DP = 7657'Ibf Sealing Load:
(T C "FF) (e <<e(t> aa(<))
F seal 'in()) + Ii cos())
F seal = 13000
~Ibf USE F seal
= 669 lbf from ATT. C MOVtest "W+" PF "stem+ F DP+ F seal T:
Torque Reaction Factor:
Required Thrust T = 8840
~Ibf Limitingavailable thrust from MOVtesting equals 9,027 Ibf. for weaklink and 11,394 for motor stall (see attch. C) which is sufficient to overcome the required thrust.
Chk:
Rev. No.: 0 Attacl.
t 3, Pnclosure 3
a Gale. No.: 94108-C-1 By: Steve reer calculation Sheet Date: ~/'/ 5& Sheet: ~+
Date: li l ~
3.2.4 VALVE 871 A & B (3"15'elan FW gate)
Calculate the value of thrust required to liftthe valve 871A/B offits seat during the limiting pressure differential specified in section 3.1.4. See ref 5.11. for design input.
Disc Mean Seat Diameter Stem Diameter Hub Diameter Bonnet Pressure Pressure Upstream (pump side)
Pressure Downstream(Rx side)
Stem/disc Weight **
D D.'=2.875 in D S.'=1.125 tn D H '.=1.625 in PB.'=1533.0 psi PUS'3.0psi P DS '= 33.0psi F W.'=20 Ibf Stem Factor Packing Friction Load Disc Seat Angle Friction Coefficient Closing Thrust Poisson's Ratio "assumed value FS:=.0116 ft FPF '.=1000 Ibf
$ :=5 dcg TC.'=8000 Ibf v =.3 DS 2
Stem Area:
AS.'=
4 A S =0.99'in
~ 2 DD Seat Radius a.'=
2 a = 1.438'in DH Hub radius ro'.=
2 r0=0.813 in Since the valve is a flexwedge calculate the advantage provided by the hub diameter b:=ro Calculate geometry factors IAWRef 4 Table 24 case 2d C3. + 1 In + 1 1
64 2
4 2
2 ro ro ro ro a
+4 4 2+ In 1
a a
a a
ro 1-
~ 1+2 In 2
4 1
L 17 ',=-.
4 4
2 1-v 0
0 a
I+(1+ v) ln 1
4 1
a a
ro 1
b 2 C8.'=-
+v+(1-v) 2 1
a Calculate the unit force acting on the hub circumpherence due to the differential pressure acting across the upstream and downstream discs (ref 4 table 24 case 2d)
Upstream Disc:
C2 L17-C8 L 11 Uses' B Us)'>>"
3' Q bus 726 Ibf C2 L17-C8L 11 Ocsmsireem Disc:
QSS,.=(PB - PUS)>>.
C2C9-C3 C8 Calculate the net unit force acting on the hub from the disc differential pressure Q bhubnct '
bus Q bds Ibf Q bds =726 Ibf Q bhubnct
achment 3, Fnclosure Gale. No.: 94108~1 By: Stev Greer Rev. No.: 0 Chk Calculation Sheet Date: II t'~Sheeh~2-Date:
l Calculate the unit force acting on the hub circumference due to the differential pressure acting across the hub area, treated as a line load due to hub stiffness nb Hub Area:
~bhub'PUS PDS)'nb Translate the hub unit force to the disc seat (see ref 4 table 24 case 1b8 2d) 1bf Q bhub b
B US 2('-
)
Q aus =-323 111 b
B DS 2
Q.e"=Qbe'
('-'
a 2a a
ro
< ahub '= (< bhub+ <bhubuet)'bf Q d =-323' 111 1bf Q ahub Total differential pressure force acting on the disc seat:
F itha
'.= (Q aua+ Q aita+ < ahab)'2 ea F d~
5839'1bf Translate to stem force due to differential pressure
-F disa
'11 FDP '=
~<4)+
1 'W4)
F Dp 2808
~Ibf F stem.'=PB AS F stem 1524 lbf 2pFS TRF:= 1-DD TRF = 0.952 Calculate the sum of all the stem forces Calculate the remaining stem thrust terms Stem Differential Pressure Load:
Torque Reaction Factor:
Sealing Load:
(Y C
~ pta)'(e ~It)- aiutk))
F seat:=
sin($) + 11 eos($ )
F sea1 =4915'1bf USE F ~g.'=2202..1bf from ATT. C MOVtest FW+FPF Fstem+FDP+Fseal T:=
TRF EQ. (1)
Total Required Thrust T =4735
~Ibf Umiting available thrust from MOVtesting equals 13267 Ibf. forweaklink and 14846 for motor stall (see attch. C) which is sufficient to overcome the required thrust.
Qi