Revision as of 23:02, 19 October 2019

Text

Informs of Necessary Change to Operating Procedures to Require Throttling Lhsi Pump Discharge Valves During Recirculation Mode of Pump Operation in Order to Assure That Lhsi Pump Cavitation Does Not Occur During ...
	ML19093B008
Person / Time
Site:	Surry
Issue date:	08/29/1977
From:	Stallings C; Virginia Electric & Power Co (VEPCO)
To:	Case E, Reid R; Office of Nuclear Reactor Regulation
References
	Download: ML19093B008 (12)
	v • d • e

/I (

e VIRGINIA ELECTRIC AND POWER COMPANY . 1£ rLECOPYi

. RIOHMOND,VIRGINIA 23261 3o, ---- ~ ..

.... ..

,;

..,

.*,.:.., ~ ~-- ;~ :

August 29, 1977 Mr. Edson G. Case, Acting Director Serial No. 374 Nuclear Reactor Regulation PO&M/ALH:das U.S. Nuclear Regulatory Commission Docket Nos. 50-280

__ , Washington, D.C. 20555 50-281 License Nos. DPR-32 Attention: Mr. Robert W. Reid, Chief DPR-37 Operating Reactors Branch 4

Dear Mr. Case:

During our meeting with your staff on Wednesday, August 24, we reported that there was adequate NPSH for the proper operation of the LHSI pumps, but a detailed investigation revealed that the. NPSH availab_le is inadequate to -pre-vent cavitation during the recirculation*mode of operation. When it was dis-covered that heat transfer assumptions-*were not the most conservative for NPSH

considerations of all safegiiard pumps pumping from the sump, our primary effort was directed toward analyzing the eftect on the RS pumps and assuring their c_ontinued operation following a loss of coolant accident. The results of this

~nvestigation were reported at our August 24, 1977 meeting.

Our extensive review of the adequacy of NPSH for the ~HSI pumps revealed two findings which had not been taken into consideration prior to our August 24, 1977 meeting. These were 1) a 3 ft. difference in elevation of the reference point used- to determine NPSH and 2) a maximum flow in. excess of that considered.

When these two findings are considered, it becomes necessary to change our operating procedures to require throttling the LHSI pump discharge valves during the recirculation mode of pump operation in order t~ assure that LHSI pump cavitation does not occur during any mode of operation following a loss of coolant accident. The injection phase of pump operation will not be affected by this change in procedure and it has been determined that the LHSI pumps will operate as designed and perform their intended function during the injection phase. It has also been determined that the maximum throttled flow (3500 GPM) is more than adequate to cool the core during the recirculation phase. A more detailed discussion of our findings and results of the analyses which support these findings are included in the attachment .to this letter.

The proposed procedure change has been reviewed by both the System and Station Nuclear Safety and Operation Committees and it has been determined that the change

~

COPY SENT RE.GiON .:J.t, A

(

e (

e VIRGINIA ;EU:CTRIC AND POWER COMPANY TO Mr. Edson G. Case Page No. 2 does not constitute an unreviewed safety question. Also, the proposed change will in no way affect the health and safety of the public.

Very truly yours,

-/~ .. J.')/) ,

(_£,,, /, . f /.

U,? JP?,*

-:L,>T., c...,.t..c/ / '- :,_ /,,:J_,,,

,-, ..

C.M. Stallings Vice President-Power Supply and Production Operations Attachment .-'

cc: Mr. James P. O'Reilly

e (- -

LOW HEAD SAFETY INJECTION PUMP NPSH INTRODUCTION In the event of a LOCA, the LHSI pumps initially inject cold borated water from the Refueling Water Storage Tank (RWST) into the reactor core. When the RWST level reaches the low-low set point the operator shifts LHSI suction from the RWST to t;lle containment sump. The LHSI discharge is then directed to the inlet of:the -High Head Safety Injection.(HHSI) pumps in addition to the existing flow path ~o the primary coolant loops via the cold legs. Approximately sixteen hours after the initiation of LOCA an additional discharge flow p~~h to the pri-

.,

mary coolant loop hot legs is also opened.

In the event of a major loss-of-coolant accident; the vapor pressure of the water in the containment sump supplying the LHSI pumps during the recirculation phase is closer to the containment pressure than the original analyses had previously indicated. This situation will result in inadequate NPSH at the LHSI pumps at specific times during the recirculation phase of long term core cooling if LHSI pump flow rate is not restri~ted.

j LHSI PUMP CHARACTERISTICS The pump manufacturer, Byron Jackson, was contacted to confirm the pump NPSH re-quirements. During the conversation, it was determined that the NPSH information which S & W obtained was referenced to a pump casing nozzle which Byron Jackson had been informed was 3 ft. above the pump suction nozzle center line. Figure 2 shows the NPSH information obtained from the pump curve and the NPSH corrected to the pump nozzle center line.* Therefore the NPSH required is 3 ft. more than pre-viously assumed.

Figure 3 is a record of the conversation with Byron Jackson.

ANALYSIS A review was made of the NPSH available to the LHSI pumps at the time that the suc-tion flow is transferred from the RWST to the containment sump. Table 1 lists the parameters used for the analysis.

Both normal and minimum safeguards were considered. All results indicated that while the switch-over point was earlier for normal safeguards there was an increas-ed NPSH of about 3 ft over the comparable minimum safeguards case. Therefore, the minimum safeguards condition is conservative for NPSH considerations.

Figure 1 shows a PSDER containment transient with minim'lllll safeguards. The NPSH resulting from this transient at the point of switchover and 15 min later is shown in Table 2.

(

- (

e For a LHSI flow rate of 3500 GPM, the NPSH available at the time of switchover is 16.5 ft. as indicated on Table 2. Figure 2 indicates a NPSH requirement of 17.0 ft. at 3500 GPM for water at 72 F. When correction is made for water at 169 F, the pump manufacturer has indicated a NPSH requirement of 16.0 ft. or less (telecon).

Further, test information indicates acceptable short-term pump operation at an available NPSH of 13 ft. Therefore, there is adequate NPSH to ensure LHSI pump operation at switchover as long as LHSI flow does not exceed 3500 GPM per pump.

As shown on Figure 1, there is a small but sharp increase in containment pressure immediately following switchover. Since the sump temperature continues to drop, the result of the pressure increase is an increase in avB.?-labr~NPSH of about 3 ft.

Table 3.show~ ,the safety injection flow required for decay "heat removal before and after the time of LHSI switchover. Since at these times conditions are relatively stable, the decay heat represents the energy being removed frQlll the reactor. Prior to switchover, there is adequate cold LHSI flow to remove all energy as sensible heat directly to the containment sump. Since there is little or no energy being added to the containment atmosphere, the containment atmosphere temperature, and thus the containment pressure, is controlled by the recirculation spray temperature.

Following LHSI switchover from 45 F RWST water to 169 F sump water, the flow is inadequate to remove all energy as sensible heat and some boiling must occur. The steam added to the containment atmoshpere ~ncreases the spray temperature, which accounts for the increase in contai!IIllent_'pressure.

As long as LHSI pump flow is restricted to a maximum of 3500 GPM per pump after the point of switchover, no NPSH problem will exist. Adequate long term cooling is pro-vided by 3500 GPM LHSI flow from the containment sump, since table 3 shows that this represents more than ten times the re~uired flow.

IMPLEMENTATION OF FLOW RESTRICTION

.The necessary flow restriction of the LHSI pumps can be implemented as an interim measure by manual manipulation of valves in the discharge lines.

The manual manipulation of valves was selected because:

a. Flow reduction is necessary for the recirculation mode and manual con-trol allows the most rapid implementation of flow restriction.

b. The available flow measurement devices can be used to monitor valve'move-ment.

c. The time available to initiate manual action (valve partial closure) is sufficient to eliminate the need for immediate operator response follow-ing a LOCA.

The reduction in flow would eliminate cavitation, thus providing assurance of long-term continued operation of the LHSI pumps.

The implementation is procedural and does not affect continued normal plant opera-tions. The LHSI pump reduced flow does not require any restrictions on normal plant operation.

(

e Under LOCA conditions, implementation of LllSI pump flow reduction does not jeo-pardize the safety function of the system ( ade.quate emergency core cooling water flow is maintained and single failure requirements are satisfied).

The reduction in LlISI pump flow is accomplished by partially closing discharge va-lves* at local valve stations outside the containment. The reduction in flow is initiated at the start of the recirculation mode via valves in the discharge of the LHSI pumps. The flow from each LHSI pump is l:illlited to a maximum of 3,500 GPM. At a subsequent time in the transient (_i.e., 16 hr.),* hot leg recirculation flow is established, necessitating a further reduction in cold leg flow in order to limit the total flow from each LllSI pump to a maximum of 3,500 gpm. The man-ual partial closure is monitored in the control room by using_installed LHSI pump flow meters. Communications between;J:.he individual manipulating the valve and the control room are required and available.

This method of LlISI flow restricticn is an interim measure only. It is planned to evaluate the entire spectrUI:1 of LOCA effects on LllSI pump and RS pump operation and propose a permanent long term solution which will assure adequate NPSH and system performance under all LOCA conditions.

SAFETY EVALUATION

..

A. Safety Implications -, The proposed modification does not affect normal power operation. The operation of safety related equipment during ac-cident conditions is affected~by the proposed modification since addi-tional procedures are required to limit LllSI pump flow during the recir-culation mode. Additional procedures are also required to assure the calibration of the LlISI flow'transmitters, monthly.

B. Review of the FSAR - Section 6 of the FSAR states that the LHSI pumps.

deliver a minimum of 3,000 gpm*and a-niaximum of 4,000 gpm each. The proposed modification requires that the LllSI pumps be limited to a maxi-mum of 3,500 gpm during operation in the recirculation mode. The pro-posed modification does not reduce the flow pelow the minimum stated in the FSAR.

C. Unreviewed Safety Question Evaluation

1. Neither the probablility of occurrence nor the consequences of an ac-cident or malfunction of equipment important to safety and previous-ly evaluated in the safety analysis report is increased. 'J.'.he mod-ifcation does not apply to the injection phase of LllSI and therefore the 10CFR50.46 ECCS analysis for peak clad temperature has not peen affected.

In addition, the long term cooling requirements for LlISI are met and therefore this phase of LOCA is not affected. The proposed modifica-tion does not affect the probability of occurrence of LOCA because plant parameters which could affect LOCA are not changed.

2. The possibility for an accident or malfunction of a different type than any evaluated previously in the safety analysis report is not created by the proposed modification. The operational mode of the

(

e te LHSI system as a result of this modification is within the design capability of the system.

3. The margin of safety as defined in the basis for any technical specification is not reduced by the proposed modification.

The operating parameters resulting from this modification are not discussed in the basis for any technical specification.

D. Smnmary - The propos~ modification assures that the LHSI pumps will be operable during ldng term cooling following*a LOCA by eliminating the liklihood of pump cavitation. The proposed modification does not cause LHSI flows to violate minimum flow rates required for emergency cooling operation in either the short or*long term.

(" - (-

/

TABLE 1 NPSH EVALUATION* PARAMETERS Break Type PSDER Single Failure Diesel Generator Initial Air Partial Pressure, psia 9.02

.,, .

Ihitial Containm.ent'Averag"e Temperature, F 125 Service Water Temperature 85 RWST Temperature, F 45 Usable Volume, gal 352,000 Volume Remaining When ,;

Spray Stops, gal 50,000 Volume Remaining When LHSI Suction is transferred to Sump, gal 25,000 6-Containment Free Volume 10 cu ft 1. 753 Spray Thermal Effectiveness, percent 100 Outside Recirculation Spray Flow, gpm 2,000 Inside Recirculation Spray Flow, gpm Below 11 ft NPSH 3,000 Above 11 ft NPSH 3,300

All Values Conservative for NPSH Considerations

( e ( e TABLE 2 NPSH AVAILABLE FOR LHSI PUMP AT 3500 GPM

1. Time at which LHSI suction is transferred to sump, 45 min Containment pressure, 10.5 psia 24.8 ft Vapor pressure of sump *:.water, 169 F - 13.9 ft

.-'.

Available due to sump* subcooling 10.9 ft Static head above pump centerline 13.1 ft Friction loss in suction line -7.5 ft Total available NPSH 16.5 ft j .

2. After switch to LHSI recirculation, 60 min Containment pressure; 12.5 psia 29.5 ft Vapor pressure of sump.water, 165 F 12.7 ft Available due to sump subcooling J 6. 8 ft Static head above pump centerline 13.1 ft Friction loss in suction line -7.5 ft Total available NPSH 22.4 ft

(

e (

e TABLE 3 SAFETY INJECTION WATER REQUIRED FOR DECAY HEAT REMOVAL 2,700 Seconds (End of Injection Phase) 153,000,000 Btu/hr Decay heat rate

-.-

-~-

Containment pressure at 10.5 psia Saturation temperature at 195 F Core Sensible heat removal From RWST T, 45 to 195 F 2035 gpm required 3,000 Seconds (Recirculation Phase)

Decay heat rate ,; 147,000,000 Btu/hr Containment pressure at 11.5 psia Saturation temperature at 200 F Sensible heat removal recirculating from sump T, 165 to 200 F 8,400 gpm required Boiling incore 165 F to 11.5 psia 290 gpm required

i ' I ! I e : ! I I

( e I j ! I i I i I I I I I I I t i i -: I I! I ! I ; j : I

' i i I i : I ' '

I I

1

'

1

! r i I I I

I I I I I I I I I I I I I I I I I : I I I I I I I I :

!

i

I I I I

I

' I I I !

i i :

i

'

i

!

.... ..,:

! I

!I"

! I I I

I

'II V I

*:

I

-

I /

i

!

I i

i t

I

! 1 I I ! I I I ' I : I I I I ! I I I ! ! I I_, nntJ- :, ,..., ** ,.,,,r, I I '

j I I I i I ! I I I I I I I I I Ii! I I ,1 I JI i ! i .' .- ... I : I I j j : : :

i ! I : : ! I i I I ! I I I I I I I ! I I i I I *-1' I I I i :-1 I I : I ! l I ! ' ! i I I I I I i i I i ; I i I I I I I I ' I i : ,* i I T I : i.:..** ; : I

l : ! t l I I I j 1 I I I I r- : I I I : ! i I I i I i I I I I I I ~ I I I : i I i I I I I I ! ! , ! ! I I ! : I I J j I

: l : I I ! I i I i '-* I I : I ! I I ! I I : I I I I i I I i I ! ! f I

I i I I ! ! i .,. ,-, I I i i I ' I i ! I I I I ' I , I : I ! ! ! I I 1. i ! l I I

' : : l l r 1 v1: II! 1:11 l!l! il I I! I ' I I J I i I I : i I ! i I I !

! l ! I 1

I i I j i

1

!~I I j-;-,

I!...

1""11 1

I I:

I I i 1 I I; 1 I

' i I I i I I

I I

i I !

I I i i !

I I I I ' I i j I l I ; ;

I I

! i

~

'

!

' I

! i I I ; ft. J ! In ';'\. I ! : I I I I I I I I I ! ! I I I I : I I ! I 1 I ! I VI i I

! : ; I I ,_,, ! ~ 1

- I I I I , I I I : : I I I ; I I ! ; I I I I I -i

! I ; If i .... / l l I I I ! I l ' ' : I I I I j I I I ! ! I I I I ! I I

! I ; I I I I ! I

! I 1"1'"' I I ~I 1....:1 I I ! i ' I I I Ii I I I I I i ! I I ! ! I : i I I I 1 lt*Jt., 1--: I i I I ; 1 I I I I , I I ' I I I I ! ! I I ! 1...-: l

I I I i ! , '-1 ;1, ! 1 I I I : 1 : , I I I : , I l I "\: ' : ! r I ~

I I I I 1 11, I I,:- ! ! I ! : I I I i I I I i ! ! : I I ; I "':' I I : I 1 fo-- ! I .1,1 I I

: -..i I*,~ I ! I I I I I I I I i I i I ! I I I ,q.: : I ! I ! ! i ! ~: i I I ti ! i I IL i 1UI t~ I Ii! Lf 11 ! ! ! Ii ! I ; I ! I ~ I i I I i ! I ! -! . - ' I l':J,i I I

- -

fl ! : ; :- I_...,. I i I i i I , I I i I I I I i I I I I i ~ ! i : ! l l ' '\JI o*

! ! : Ii -

I .;

I

, *tn,

~I ;

~

I

,

I 1 : ,

'

, ,

Ii

, 1

!

1 1 i I 1

11

,

I 1

11.,1

, ,

I I ;

I ,,

"' ! :

i I

I !

I

!

I I

..,.,

UI:

'

CX) : I I i : ; ! I

. ,, .

- ~. I I I t-,..*

0 ! !

I ! ;

! i I , .,

i 1 _-

I :~

i I I

; -'--1 I i ~ I I I I I i

I I i-..1. I i

i I

, I i I

! I I I I I I ' i

, I ! I I I I I I I i i i I I

i I I

/

I I I

I i i i i I : I I i I

i i

!

I j

i ~, J : I I I I

!

1

! :

I I i :

i

!

i f I I

1"'-1'1 I

'1:: , I t :

I.O

'<t. i : i I ( :.., i I --, ! ~1 ! : i ! 1 I 1 ! I 1 1 I 1 .,. II I i I J I I I i \ i I I I I I ,, ! -. ' i ! ' ! I I i I i/ I I I *°'"' I ; I I I I I i i '"""'-* : I

'I 1 £1 ! i I ; I, i I ,., 1 I I ~I i ! I ! -:-:: : :

I I

I

I 1

I iA I I I 1 ' I 1

I

! I

'

-, I I I I

I

' I I

,.....,i

' I : 1,i11"'-a.. ! I~ I **r; I

111 1111 *-IN I: Ii I I I I I I ., I I I I i I i I I / t I I : ! ! !_ ~ --~ I I ! r ! ! I I ! 1fll *1 I I I \ I : I I ! i I ' I I I i I I I ! I I

-,L ' I /: ' " " '\I ! I I I : I , ' I A }/1 I I I I I I 1 ' '\a I I I i ' i I

! i r~,......_ '!- I-ii 1!!, I!~-../., I I ii.! llli *'\ II i, I ' I u: i I

' ' I ! ' - 1 ..._) I ! I I I I ' I "<Jf I l I I 111 1 i I ! I' I ! 1 I i ! I I I i ' I 1i 1, I > I II I \ 1 I I I i i I I : I 'l /I I I I I "" I I I I I "\.I I ! I 1 ' i 'I!, I !

! i I I I 1 ; 1-:- I I ! ! I I I I !-I~/! 1**1 I I i : IN I I I ! 'I I Ii I I I I I I I : I : I I , i ' I I I I I i i !, I I i :J,'.I. : i i I I I I ..- I i I I I , ,1 1 I i I : I ! i I I ! : ! I I I ! I I ' I ; ! I ; I "-*7: I i I I ! I I I~ ' I I I ' ! I I ' I ( I t: I I I

I ! : I I I I ! I! I ' I I I I -! '-' 1 .i I ! 1 I I '":1 I Ii I I I : I ! ' : I ii~ 1 I

! 1 I : , I I , i i I I I I I i : 1 ~*! / ! *i I I I I I : 11 .- I I I i ! I I I '\ 1 1 ; ! I I Al, I I

' ! ! I I I I i I l I I I I i i it.I T I i 1 I i I I I I t i 1 {I I j i I j 1 ! ! '\. I I i ! I ._ I I i l i 1 I I t I I i I I I i :,l'.J i i I ! l f 1 I I I i i t 1 I i , 1 ! 1 t .,: 1 ! I I 1 i i ! I I I 1 I i I I I I ! l. *-z I i I I i I I I i I , .,. 11 I ! 1 I I I I i I '\ ' I ! : i I 1;-; I :

1 I : ! I I i I i I I I I I ! 'T I* I I I i I I I !""t. I , I I I i I I i i'\1 I I I I I.~ I l I l I I I I I I ! I : I I / i I I ' , I I i I I I /I I I I I I I I '\ I ! ".J I I * "°'! ! I

, I I I ! i ; I I /' I I I I I I! I I L: l : I I I I I I ' '\I '"'I I -; ~ I I

' I I I I I I I I I I i I i I I I I I I , i I I I i ~ Ii Tl ! I I ! I i i i I : - 1 I ~ I I I I I I 1 I I I 1 I I I I I I/ I I' ! i I I I I I I I 1,.11' I I Ii i I I I I , ._I I .l... I I I ! : I I I , I ,111 IIYI 1111 1;11 11,1 11.:..ll,I' I I 1111 ill! '!oJ 1 1 ~ 1

!!

: I I I ! I I I Y! i ! I I I I , I I I I 1- T?*'I' 1 I i I I I I I I I I I I I i : I ! ,.._-, I i I I I 1 t I ! I/; I ! I I I ! l I ~ I I ! \ :..._, *:~ ! ! i i I I l I I : ! I I ' I "'-ii! \

I ! l i ! 1 ./: ! I I I i ! I I ! I ; ! i I \ I ,./1 I I l 1 I l I I I I I I I : n... I! 1 !

I i I ,{ 'r,.;;,. I I

' : i I I I I I I I I I i i I !/ I I I I I I I/ I I I I I i I I

i ' I I I '

, i I I 0:. ,r. ..,,. . .,~-+,-+-+-1-+-~,-+-+-~1--+-+I I I I I I i I I I ! ! I I i ! I '

-1~,---,_.._,_,-+1-1-+-,-+--+l-+l--+-+-1-o---;-1,-....11--+*\.I-~!~!-+,-<

..... I I i i I I I/, I I ! I I I : : I I i ! .... -./ I : i i ! I I i ! I i I I I i : : I ' ,.... !

, I I f I ! ! I I l 1 1 l ; I : I ( .. - ; i 1 i I I I l : I l ! ! I I I 1 ; I : I l I I ' I ! ., ; I I I I I I i I : ! /: ! I i I ; I : ! I : I I ! ! I I ! j I I' I 1 : i I I i l.l'i : I I I I I , ! I I , : I ' ...-, i i I I i I I ! I i : i I I ! 1 I -'"I' i '

I !

i I I '

! ; I I t I !

I I I I

! J 11 I I I I

! I I I

I

;

I I l I/*\!

! ,., : I I I I l i I I I I

! ! I i ! :

I i I I I I

I I I !

! i I I i i I '

I I I I r I I I i j i

i I I

--

,;, - i ;

....:' I

! !

' I I '

i I i i I I j I : I I : I I I I II : ; I I : I I I : I ! j I l ! I f 1 .,.,,,,,,..., I I ! i ! ! / ! I I I I ' I 1 I ! I I ! I , 'I i j ! , i i I i i I ! I I* ,_,r i ' i ! i I I I I I I I ! I ' ! I I I I i I I : I !

I ! I I I ! I I I : I ' I I I I l'1 ' I I I I : I I : I I : I ! I I I I I I I I i ! i l I I I I I I I I : I I l : I ; I I I l,"'1'" : I ; I I ' I I i I I I I I ! I I I I i I : I I I ' I ! I I I I I I l : , ! I ! I I I ! ! i ; I i I I I I I I i I I I , I ! I I ; I , : I I ! ; i ;

I : I I : I I I i I i I : I ' ' ! I I I i I I ! I I I I I I I I I I I I I I I i i I I I I I ' , ! I I ! I ' I i , I I i I ! I I I I I , I ! I ! I I I I I I I 1 I ,~,, I I

' I i i ! I t I I i i I ! , ! I I I ! i I : I I I I I I I I I 1 I I ! I ! I i : i I I

! I i r I I ! l I : 1 l I ,i 1 1 I i I I I I I ! I I l I i I l i i i :

, I i 1.. 1 : I I ! i I I ; I : I i i'"' ! I I I i I I ! j : I : : - ; ! I I I I I I~! ... I I I I I I : ; I : ! ; - JI ! l I I I . ' ,; I I ) ---* ! i I I I- i I : ! I I* I I I I, i I I ; I :

1

! I ! i 1 : l *: I 1 l I I

' '

i '- I !

I

!

I I :

'

, I I

I

'

! I I I ~' I I I I ' I ! I I I : ! I ; I ! : I ! I I ) J ! I I I I I I I ! I ,' I . i I I I i

I I ! i I I ! ._J i J.n I ,.,.,. l...,,1 ~.Jr~~I I I i I i I

' ': ' I ' I I ; ...- Cil ! I ;

I I i j ! i I : ! ! : i ' I I I I I I ' ' I ! ; i I 1 I i I I I I i ! I I I I I ! I 1 I I ! I I

! ! ! ! : ! I ' ' : I I I : I i ! I I i ! i ! ' : I I I

! I : i i I I : ! i ;

i I i ! I I i ; 1 i I

I I I ! 1 \ I I ! I I I" I ; : .\ I I '

If' I 1 I ! I ; ! I I I I ! I I : ; I I I I f I ! 1 !1, , I j '. : *I I I I 1. I I I I j I 1~,1 ! 1 : : i I I

! I I i I I I ! ; t I i 'Ir-: ,' 1 i ! j -/ I I I I I I I ' I ' r i : I ! I / i I : I / ;

I I I I I ; !

_,,C!' '* I I I !

! ; : i I !

i I ! I I I ' i 1 i l I

l 1 i .* ,. 1- - I - ~ - - -i :--: " I -, I I ! I

/ 1 l I ,I j ! ; I I I i ! I 1 I I I I I : ' I i i

' I i i i : i : I ' : I I i \ -I 1 ! I

10 X 10 TO THE INCH* 7 X 10 INCHES KEUFFEL 6: ESSER CO. MADE IN U.S.A 46 0780

-** - -- -

I - - -* ~ - - - * *

--l-- --~---- -* .. -- ----1--

-* *- - *- * ~ -C) ~!5 I~ --**- -* * - --~-1--. - - -l(i.1, t:: 1~- - -- - - -- - -- *- .I J, i ~ l - *- -* -* *- i 2 r, rilrl"

- - *-*--***- *- -- ---- - - ---- _ ,_ -k..... .* L- --- . - --1-- - - *- . - --l-- -- - -- - - L- -----------

- -- - ---- -

-- - - -,- . - - . - - - -- -* - .*. 1--. -- - - - - -* - -* .. - l- . --1---- ****- -* - - _,_ - -* -- - - *- -* ( - __ ,_ -* *-* - -

--l.-l-j._...__~- -- _ - - - --- - - - __ ! *.* l *-. - l --

- -~ - --

--- . - -- ..-. - - ~ *- --* - -,-f--+--1--1-1-1 i- - i-~ .=- _L_ -L- _:_~.1. . --~----~'...

-

_-~f-,_ -.-. i-_-,:i:_~_l;;.1--~=-::_f-~:-*:_~~--~~- --*-=.

r- __ ,-- --- -

L.___._ 1-- - -- - - .. -L- - - ** - ** - I - - - - - ,* *- - .

~-~-=~= *=-~-~

-i---f---1---'--*---

~L= =~.~~~-L=I= :~I=,=~=-=- ~~:=~-L-

l.--i.,_i-*---*-i--.--1--------- ~-

--~--~-1---~. --~--- ~-------------- j

)

e

~-

- *- . 1.. - ..

e ""' ..

1*--

ii

-- - - - f-- *- - I--**- -- - *- -- -- *-~-i.. *. -- - *- . -- - f - *- l7~ *- -

_,_ . l, .-1----------L--- *---(- --1---f----- -+--( ____ --1-- . . . . . . -.L- ___ _

~ ::::::*_::::::*:::*:::*:~*:::.:::::: ==:::::::::~_:::: .: : ~. ~-; __ ,=*:::~*= :::::::.~ - -*** -' ,_ -- -- *--* ---- -*- -~ *-**-- -- - . -*'- - -- - . *- -

...,. *- *- 1-- -- - - *- - - *- -* - - - - -- -* tJ ..... - .. -* ... -- **t-- - -- L._ - - - * .*. - - - - - -- -- -- -* _.__ ** -

1---l-- - - -- - -* - **- *--1-- -* -- ... L ..

I~

- - - ~ ';** - _,_ 1-- **-+- -- . - L- - - - *. - - -* -- *- - ~ - -* -- - *- - - **- *- --L-- - - -- - --

__ i._ - - ,.... - - *- - - - *- -- -- .. -* .... *- -- -- - - -

- - * - - - --~----- -*-~-- ------1----1--**-+-- __ 1-1.._, _ _ 1 - - l - l - - - - 1 - t - f - - - * - * * - * - - - - ____ 1_ ---- *-'-

- - -- _,_ -- *-'-- .** 1.. . 1._ - -- - -- --L- -* -*- - -- - - --1--* - -- __ ,_ -* - .

,_ ___ ,_

L- -- - ,*

-- _L..__.

-- --- --* --- .. - - *- -- ---- --- -----~ ....

- ---*-*- - ___ ,___ -- -* ----

- **- _L__ * . . * -- * * ' - - - * *.. - *-** - -- *- -* -- - *- ---- -*- --- *- -- ..

I I

... c*e FIGURE 3 NOTES OF TELEPHONE cmrvERSATION .,

DATE Augnst 26, J 977 TIME___.l=l;;.;;.:....

30.;....;.;A=.M;;..;..;;.....__ OOTGOING *J.C.------

~

BE'IWEEN* J, H, NOBU: OF S & W Bob Robinson OF S&W Marco Avila OF Byron Jackson

-~.:_

,

OF *213-587-6171 SUB.Jl,6T Surry IBSI Pump- Test

SUMMARY

MA described the test rig. Since the actual pump casing was not available, a substitute casing was used. NPSH was measured just outside the inlet to the ca.sing. The pump impeller center line was 10 ft-2 1/2 in. below the point of NPSH measurement. Since; the NPSH was measured outside the entrance, the test point included entrance and velocity losses. I asked about pump operation with cavitation. MA replied that ~he test had included a point with 3 ft less NPSH.

He would not have concern about operating at this point for an hour or two*but I.1* would have concern over days. I ask-ed a-bout ..a. ~duction in NPSH -due to a water I

temperature of about 165 F instead of the test temperature of. COPY TO ALL PEESONS IUVOLVED 72.F. MA replied that there would be at_ least a 1*ft reductio IN CONVERSATION PLUS:

but he could not say whether it would be as great as 2 ft. I asked about the NPSH curve shown on the pump curve transmitted to S&W from Wo MA replied that the information available to him at the time. the curve was*drawn indicated a field nozzle in the*casing 3 ft-above the center line of the pump impeller.

The NPSH was corrected to this nozzle location.

ML19093B008: Difference between revisions

Revision as of 23:02, 19 October 2019

Text

Dear Mr. Case:

SUMMARY

Navigation menu

ML19093B008: Difference between revisions

Revision as of 23:02, 19 October 2019

Text

Dear Mr. Case:

SUMMARY

Navigation menu

Search