ML20087G168
| ML20087G168 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 03/31/1982 |
| From: | MPR ASSOCIATES, INC. |
| To: | |
| Shared Package | |
| ML13309B380 | List: |
| References | |
| PROC-820331, TAC-44622, TAC-44623, NUDOCS 8403190351 | |
| Download: ML20087G168 (86) | |
Text
l r-ATTACHMENT B Revision 1
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EPRI PWR SAFETY AND RELIEF VALVE TEST PROGRAM GUIDE FOR APPLICATION OF VALVE TEST PROGRAM RESULTS TO PLANT-SPECIFIC EVALUATIONS INTERIM REPORT, MARCH 1982 (RESEARCH PROJECT V102)
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ABP E A4 MTM MP RFP AMD Prepared by:
MPR Associates, Inc.
1140 Connecticut Avenue, N.W.
Washington, D.C. 20036 Prepared fer:
Participating PWR Utilities and Electric Power Research Institute 3412 Hillview Avenue Palo Alto, CalifcInia 94304 EPRI Project Managers:
T. E. Auble J. F. Hosler PWR Safety and Relief Valve Test Program Nuclear Power Division 8403190351 840314
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Revision 1 PREFACE This guide has been developed to assist participating PWR Utilities in determining the applicability of the various test results from the EPRI program for their plant-specific evalu-ations. -The overall key to using the guide is to most closely match the valve / piping configurations tested by EPRI with actual plant installations.
In following this approach care should be taken not to overlook the results of any test for possible applicability, i.e.,
each test conducted on a representative valve type may have some generic or indirect applicability.
However, the closer the tie between specific EPRI tests and the plant installation, the more direct the applicability of the results.
It is expected that the approach developed in this guide will be useful for virtually all of the plant evaluations.
e
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Revision 1 TABLE OF CONTENTS I.
INTRODUCTION A.
Purpose of the Application Guide B.
Contents of the Guide II.
PROCEDURE TO BE FOLLOWED IN PLANT-SPECIFIC EVALUATIONS i
A.
Flow Charts for the Evaluations 1.
Evaluation of Valve Performance 2.
Evaluation of Piping / Support Adequacy B.
Workscopes for the Evaluations 1.
Utility 2.
Valve Manufacturer 3.
NSSS Vendor 4.
EPRI III.
EVALUATION OF TEST RESULTS FOR PLANT-SPECIFIC CONDITIONS A.
Identification of Pertinent Plant Parameters B.
Procedures for Evaluation of Test Results 1.
Safety valve Performance and Associated Piping / Support Adequacy 2.
Relief Valve Performance and Associated Piping / Support Adequacy l
C.
Identification.of Potential Prcblem Areas and Possible Alternatives to Address Undesirable Valve Performance l
IV.
SUGGESTED FORMAT FOR JULY 1, 1982 l'
PLANT-SPECIFIC SUBMITTAL V.
REFERENCES
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Revision 1 TABLE OF CONTENTS (Cont'd)
VI.
APPENDICES A.
Procedure for Calculation of Valve Back Pressure B.
Procedure for Calculation of Inlet Piping Pressure Effects C.
Procedure for Verification of Alternative Methods to be used in Evaluation of Piping / Support Adequacy D.
Procedure for Assessment of Applicability of Specific EPRI Safety Valve Tests E.
Load Combinations and Acceptance Criteria for the Safety and Relief Valve Piping Evaluation ii
., -. _ _ = _. _..
4 I
Revision 1
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I.
INTRODUCTION A.
Purpose of the Application Guide 2he purpose of the application guide is to provide a pro-cedure for utilities to follow in preparing plant-specific submittals in response to NUREG-0737 (" Clarification of TMI Action Plan Requirements")Section II.D.1-A, Requirements.
Specifically, JUREG-0737 requires the following:
1.
An evaluation of safety and relief valve function-ability for plant-specific operating and accident conditions.
2.
An evaluation of piping and support adequacy for
.plsnt-specific conditions.
In preparing the applicatien guide, it was assumed that the utilities would obtain assistance from the valve manu-l l
facturers and NSSS vendors in performing the required evaluations.
Specifically, it was assumed that:
1.
The utilities (with possible assistcnce from architect-engineers er other piping designers).will perform the eval-uations of piping and support adequacy.
2.
The valve manufacturers will perform the evaluations i
of valve performance.
4 Revision 1 4
3.
The NSSS vendors will perform the evaluations of overpressure protection system performance.
4.
The utilites will coordinate the overall evaluation effort and prepare the plant-specific submittal to the NRC.
The delineation of responsibilities outlined above is based on impressions gained throughout the program regarding which organization (s) was probably best suited to accomplish a
/
particular task.
It is recognized that some utilities may elect to perform more or fewer tasks than assigned in this guide.
The important point is that the guide highlights
-the tasks that need to be done and assigns them to an appropriate organization.
The participating utility has final control over both the scope of work details and the organization assigned.
The Application Guide is based on directly using test results from the EPRI program in the plant-specific evalu-ations.
Thus, in order to use the guide, one must estab-lish the one (or more) valve / piping configuration tested by EPRI which most closely matches the plant installation.
It is expected this approach will be useful for virtually all of the plant evaluations.
The guide assists in de-
-fining the limits of applicability of the EPRI data.
I-2
c Revision 1 C.
B.
Contents of the Guide The contants of the application guide are su==arized in the following:
Section II -- Procedure to be Followed in Plant-Specific Evaluations A.
Flow Charts for the Evaluations This section describes the overall approach to be followed in performing the evaluations of valve performance and piping / support adequacy.
B.
Workscopes for the Evaluatiens This section discusses the workscopes for the evaluations to be performed by the utilities, the valve manufacturers, the NSSS vendors and EPRI.
Section III -- Evaluation of Test Results for Plant-Specific Conditions A.
Identification of Pertinent Plant Parameters This section identifies the pertinent plant-specific safety and relief valve, inlet piping, discharge piping and valve actuation transient l
parameters to be assembled by the utilities for use in the evaluations,
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Revision 1 B.
Procedures for Evaluation of Test Results This section provides the procedures to be used in performing the evaluations of valve performance and piping / support adequacy.
For the valve per-formance evaluation, it provides guidelines for identifying applicable valve tests, a table to l
be used by the valve manufacturer to document valve performance characteristics, and a suggested set of acceptance crit, for. valve performance.
For the piping / support au,Jacy evaluation, it provides suggested guidelines for the evaluation and a suggested set of structural acceptance criteria.
C.
Identification of Potential Problem Areas and Possible Alternatives to Address Undesirable Valve Performance This section provides a listing of potential problem areas regarding valve performance and piping / support adequacy identified based on the results of the EPRI Safety and Relief Valve Test Program.
It also discusses possible alterna-tives to be considered by the utilities to address undesirable valve performance features.
a Section IV -- Suggested Format for July 1, 1982 Plant-Specific Submittal This section of the guide provides a suggested format for the July 1, 1982 plant-specific submittal to the NRC.
I-4
I Revision 1 Section V -- References This section provides a listing of the various EPRI Program' reports to be used by the utilities in per-forming the plant-specific evaluations.
Section VI -- Appendices A.
Procedure for Calculation of Valve Back Pressure This appendix outlines a suggested procedure and guidelines for the calculation of valve back pressure.
B.
Procedure for Calculation of Inlet F_ging Pressuro Effects This appendix provides a suggested procedure and guidelines for the calculation of inlet piping pressure effects.
C.
Procedure for Verification of Alternative Methods te Ee used in Evaluation of Piping / Support Adequacy This appendix provides a suggested procedure to verify the adequacy of the alternative methods to be used to evaluate the structural adequacy of the piping and supports.
D.
Procedure for Assessment of Applicability of Specific EPRI Safety Valve Tests e
This appendix outlines a procedure to assist in determining the applicability of EPRI safety valve tests to specific plant evcluations.
I-5
Rev.sion 1 E.
Load Combinations and Acceptance criteria for the Safety and Relief Valve Piping Evaluation This section provides recommended load combinations and acceptance criteria to be used by the utilities in evaluating the adequacy of the safety and re-lief valve piping and supports.
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I-6
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i Revision 1 II.
PROCEDURE TO BE FOLLOWED IN PLANT-SPECIFIC EVALUATIONS A.
Flow Charts for the Evaluations 1.
Evaluation of Valve Performance Safety valves The flow chart provided in Table II-l illustrates the overall procedure to be followed in performing the evaluations of safety valve performance.
The input for the evaluations consists of:
EPRI valve program reports as listed in Section V of this guide.
List of pertinent plant parameters as identified in Table III-1.
The evaluations to be performed consist of the following:
An evaluation of test results by the valve manufacturer to identify any potential problem areas regarding valve performance.
An evaluation by the NSSS vendor to identify any potential problem areas regarding overpressure protection system performance.
C.
Revision 1 An evaluation by the utility of possible alternatives to address undesirable valve performance featares.
The output from the evaluations consists of:
A report for submittal to the NRC which documents the results of the plant-specific evaluations.
This report would address the selection and schedule for implementation by the utility of any required modifica-tions to the valves and/or the overpressure protection system parameters.
Although not shown specifically in the tiow chart, a significant amount of interaction is expected to be required among the utility, valve manufacturer and NSSS vendor during the course of the evalu-ations.
Also, it ir expected that the utilities will assume the re:bonsibility for coordinating the overall evaluation effort.
8 II - 2
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Ravision 1
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Relief Valves The evaluation of relief valve performance should also be performed following the procedure shown in Table II-1.
However, this evaluation should be more straightforward than the safety valve performance evaluation and it is expected that the utilities would perform the bulk of the evaluation.
2.
Evaluation of Pipina/ Support Adecuacy The flow chart provided in Table II-2 illustrates the overall procedure to be followed in performing the evaluations of piping / support adequacy.
The input for the evaluations consists of:
Verified computer codes for determination of hydraulic loads and EPRI valve program reports as listed in Section V of this guide.
List of pertinent plant parameters as identified in Table III-1.
The evaluations to be performed by the utility consist of the following:
An evaluation of the piping stresses and support loads using the EPRI-provided codes or other method which has been verified by comparison of predictions with EPRI test data provided in Reference 7.
A comparison of calculated eining stresses and loads with allowables and identification support of any potential problem areas.
II - 3
Revision 1 An evaluation of possible alternatives to address potential piping /suppcrt problem areas.
The output of the evaluations consists of a report for submittal to the NRC which provides the results of the plant-specific evaluations.
The report may include, if required, the selection and implementa-tion schedule of modifications to the piping and supports.
B.
Workscopes for the Evaluations Tables II-3 through II-8 summarize the workscopes for the various evaluations to be performed by the utility, the *talve manufacturer, the NSSS vendor and EPRI.
The tables are identified as follows:
Table Orcanization Evaluation II-3 Utility Safety and Relief Valve Performance II-4 Utility Piping / Support Adequacy II-5 Valve Manufacturer Safety Valve Performance II-6 Valve Manufacturer Relief Valve Performance II-7 NSS Vendor Safety and Relief Valve Performance II-8 EPRI Valve Performance and Piping / Support Adequacy II - 4
TABLE 11-I Revision 1 APPLICATION OF VALVE TEST RESULTS TO PLANT - SPECIFIC EVALUATIONS OF VALVE PERFORMANCE EPRI UTILITY VALVE M ANUFACTURER NSSS VENDOR ASSEMBLES PROVICES VALVE PERTINENT PROGRAM REPORTS PLANT INTCRMATICN TCR EVALUATIONS (gZZ TA,LZ III,l}
4 h
1r EVALUATES TEST EVALUATIS TEST RESULTS AND RESULTS A';D IDENTITIES ANY
'I0 ENTITIES ANY d
PCTENTIAL PRCBLEM PCTINTIAL PROBLEM ARIAS RICAROING ARIAS RE0AROING VALVE PERTCPp.AN0!
SYSTEM PERTCM'.ANCE ir 1r IDENTITIES IOINTITIES ALTIP2;ATIVE ALTIPJfATIVE VALVE SYSTEM / ANALYSIS MODITICATIONS' MODITICATIONS AS REOUIRED AS RIICIRED l
4 1r
- PROVIDES, EVALUATES ASSISTANCE gg;gpy;g;;ygg TO UTILITY IN
- -D AND SEMC S AS,EUATICN MCDITICATIONS U
REQUIRED
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1r SCHEDULES IMPLEMENTATION l
CT SELECTED MODITICATIC::S AS REQUIRED 1P PREPARES PLANT-SPECITIC SUBMITTAL TCR THE NRC II - 5
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Revision 1 TABLE 11-2 APPLIC.ATION OF VALVE TEST RESULTS TO PLANT - SPECIFIC EVALUATIONS OF PIPING ADEQUACY EPRI
' UTILITY f
ASSEMBLES PRCVIDES VERITIED COMPUTER CODE AND PERTINENT VALVE PROGRAM M
PLANT REPORTS TCR INTORMATION UTILITY EVALUATICNS (SEE TABLE III-1) 1r USING EPRI-PROVICE CODE OR CTHER VERIFIED METMCD EVALUATES STRESSES add SUPPCRT LCADS IN PIPING 1r E
CCMPARES LCADS AND STRESSES WITH ALLCWABLES AND IDENTITIES ANY POTENTIAL PRCELEM ARIAS i
l l
1r l EVALUTES, SELECTS AND SCHEDULES IMPLEMENTATION OF MODITICATIONS TO PIPING AND SUPPORTS AS REOUIRED PREPARES PLANT-SPECITIC SUBMITTAL i
FOR THE NRO 1
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Revision 1 0
TABLE II-3 WORKSCOPE FOR UTILITY EVALUATION OF SAFETY AND RELIEF VALVE PERFORMANCE The utility will perform the following 1.
Identify pertinent plant information listed in Table III-1, including:
Valve parameters Inlet piping parameters Discharge piping parameters Valve actuation transient parameters 2.
Evaluate alternative modifications identified by valve manufacturer and/or NSSS vendor and select modifications for implementation.
3.
Schedule implementation of selected modifications to valvas.
4.
Prepare plant-specific submittal for the NRC.
b II - 7
Revision 1
. TABLE II-4 WORKSCOPE FOR UTILITY EVALUATIONS OF PIPING / SUPPORT ADEQUACY The utility will perform the following:
1.
Identify pertinent plant information listed in Table III-1, including:
Valve parameters Inlet piping parameters Discharge piping parameters valve actuation transient parameters 2.
Using EPRI-provided code or other verified (by comparison with valve test results) method, evaluate stresses and support loads in inlet and discharge piping.
3.
Compare loads and stresses with allowable values and identify any potential problem areas.
4.
' Evaluate, select and schedule implementation of modifica-tions to piping and supports as required.
5.
Prepara plant-specific submittal for the NRC.
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Revision 1 TABLE II-5 WORKSCOPE FOR VALVF MANUFACTURER EVALUATION 0F SAFETY VALVE PERFORMANCE A.
Bases for Evaluation The following will be provided to the valve manufacturer for his use in the evaluations:
1.
Applicable EPR.T test program outputs.
Plant information listed in Table III-l 2.
B.
Scope of Evaluation The valve manufacturer will perform the following:
Define performance for as-installed valve ring settings 1.
based on:
EPRI test dara Valve manufacturer's test data Valve manufacturer's supporting analysis The evaluation should:
Determine which fluid conditions result in stable or unstable valve performance.
Establish valve performance characteristics (e.g., blowdown, lif t, flow opening timo, etc.).
Define performance for optimal valve ring settings in 2.
accordance with the steps identified in 1 above.
Recommend valve modifications to provide improved 3.
performance, if readed (e.g., to provide reduced blowdown, stable water performance, etc. ).
Document performance re::ommendations and bases for 4.
recommendations to the utilities.
1 II - 9
Revision 1 TABLE II-6 WORKSCOPE FOR VALVE MANUFACTURER EVALUATIONS OF RELIEF VALVE PERFORFJJ;CE A.
Bases for Evaluation The following will be provided to the valve manufacturer for his use in the evaluations:
1.
Applicable EPRI test program cutputs.
2.
Plant information listed in Table III-1 B.
Scope of Evaluation The valve manufacturer will perform the following:
1.
Establish valve performance characteristics (e.g., opening time, flow, closing time) 2.
-Recommended-valve modifications to provide improved performance, if needed.
3.
Document performance recommendations and bases for recommendations to the utilitics.
II - 10
Revision 1
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TABLE II-7
'WORKSCOPE FOR NSSS VENDOR EVALUATION OF SAFETY AND RELIEF VALVE PERFORFANCE
-A.
Bases for Evaluation The following will be provided to the NSSS vendor for his use in the evaluations:
1.
Applicable EPRI test program outputs.
2.
Plant information listed in Table III-1.
3.
Valve performance characteristics (e.g., blowdown, lift, flow, opening time, etc.), as established by the valve manufacturer.
B.
Scope of Evaluation The NSSS vendor will perform the following:
1.
Evaluate test results and document system acceptability or identify any potential problem areas regarding NSSS overpressure protection sys-tem performance.
2.
If potential problems are identified:
Identify alternative modifications to NSSS overpressure protection system and/or overpressure transient analysis parameters to resolve un-l l
acceptable performance.
Concur with system / analysis modifications selected l
t by utility for implementation.
l Prepare report which justifies acceptability of system / analysis modifications selected for implementation.
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Revision 1 i
1 TABLE II-8 WORKSCOPE FOR EPRI EVALUATIONS A.
Valve Performance 1.
Provide valve program reports for utility evaluations.
2.
Provide on-going assistance to utilities in the understanding and use of program outputs as required.
B.
Piping / Support Adequacy Provide verified computer code and valve program reports for utility evaluations of inlet and discharge piping and support adequacy.
The code provided by EPRI is to be used for the calculation of the time-dependent hydraulic loads applied by the fluid on the piping.
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II - 12
e Revision 1
(,
III.
EVALUATION OF TEST RESULTS FOR PLANT-SPECIFIC CONDITIONS A.
Identification of Pertinent Plant Parameters A list of pertinent plant parameters to be identified by the utility is provided in Table III-1.
Possible sources to be used by the utility in compiling the required in-formation are listed below:
1.
Plant Final Safety Analysis Report / Cold Overpressuri-zation Analysis Report 2.
Plant Technical Specifications 3.
Plant installation drawings and system isometrics 4.
Valve-Documentation and Nameplate Information 5.
Initial valve manufacturer's test data and periodic set pressure verification test data.
In addition, the EPRI valve program reports (see Section V) and the appendices to this guide should be useful as follows:
The test conditions justification report (Reference 3) and plant conditions justification report (References 4, 5 and 6) should be useful in assembling the valve actuation transient information.
Appendix A provides a procedure to be used for the l
calculation of valve back pressure.
l
' Appendix B provides a procedure to be used to calculate U
the inlet piping pressure drop associated with valve opening and pressure rise associated with valve closing.
- 4. 6 4
Revision 1 B.
~ Procedures for Evaluation of Test Results 1.-
Safety valve Performance,nd Associated Piping / Support Adecuacy The procedure to be used to evaluate safety valve performance for plant-specific conditions is as follows:
Step 1 The utility.provides the assembled plant in-formation-(Table III-1) and the applicable EPRI valve test program output to both the valve manufacturer and the NSSS vendor.
i Step 2 The valve manufacturer identifies'the specific EPRI tests which are applicable for the plant-specific safety valve evaluation being performed.
An outline for conducting this type of evaluation is provided in Appendix D to this report.
Step 3 Based on the information provided by the utility (see. Step 1 above) and the valve manufacturer's own test data and supporting analyses. the valve manufacturer determines the valve performance
^
characteristics and completes the performance summary sheet provided in Table III-2 for both as-installed and optimal ring settings.
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Revision 1 Step 4 The utility performs an evaluation of safety valve inlet and discharge piping stresses and piping sup-port and valve loads.
Step 5 The NSSS vendor compares the valve performance characteristics listed in Table III-2 with the valve characteristics assumed in the FSAR (or other design) overpressure protection system analyses and identifies any conditions for which the actual and assumed valve performance characteristics are not consistent (see Table III-3 for performance characteristics to be considered).
Where not consistent, the NSSS vendor should judge the acceptability of the deviation and provide the basis for his judgment.
Step 6 The utility compares the safety valve piping / support loads and stresses with the allowable values and identifies any conditions for which the allowable l
values are exceeded (see Table III-3 for definition l
i of piping and support allowable loads and stresses).
L l
Step 7 i
The utility (with assistance from the valve manufacturer and NSSS vendor as required) identifies any conditions for which acceptable valve performance l
is not obtained.
The utility then evaluates III - 3 l
I
- Revision 1 possible alternatives which could provide acceptable valve performance and selects any needed modifications to be made to the valves or piping.
Step 8 The utility, valve manufacturer and NSSS vendor prepare reports which document their evaluations and justify the acceptability of any modifications selected for implementation.
2.
Relief Valve Performance and Associated Pipinc/ Support Adecuacy The procedure to be used to evaluate relief valve per-
-formance for plant-specific conditions is outlined in the following.
It is noted that these evaluations chould be straightforward and it is expected that the utility could perform the bulk of the evaluations.
Step 1 The utility assembles the plant information (Table III-1) and the applicable EPRI valve test program outputs.
Step 2 Based on the plant information and the EPRI valve test data, the valve manufacturer (or utility) determines the valve performance characteristics and completes the performance summary sheet provided in Table III-4.
This evaluation should consider any differences in the air and/or electrical supply and for pilot-operated valves the pilot vent discharge tubing for that in-stalled in plants compared to that tested.
III - 4
Revision 1 Step 3 The utility performs an evaluation of relief valve inlet and discharge piping stresses and piping support and valve loads.
Step 4 The NSSS vendor (or utility) compares the per-formance characteristics listed in Table III-4 with the valve characteristics assumed in the cold overpressurization analyses and identifies any conditions for which the actual and assumed valve performance characteristics are not consistent (see Table III-3 for performance characteristics to be considered).
Step 5 The utility compares the relief valve piping /
support loads and stresses with the allowable i
values and identifies any conditions for which the allowable values are exceeded (see Table III-3 for definition of piping and support allowable loads and stresses).
Step 6 The utility identifies any conditions for which acceptable valve performance is not obtained, l
and then evaluates possible alternatives l
i j
III - 5 l
(
Revision 1 which could provide acceptable valve performance and selects any needed modifications.
Step 7 The utility, valve manufacturer, and NSSS vendor prepare reports which document their evaluations and justify the acceptability of any modifications selected for implementation.
C.
Identification of Potential Problem Areas and Possible Alternatives to Address Undesirable Valve Performance Based on the results of the EPRI valve tests, it is apparent that there are some plant conditions which could result in valve performance characteristics which are not within acceptable limits (as currently defined).
As discussed in previous sections, the first step in addressing these poten-tial concerns is to perform analyses to attempt to demonstrate that the observed valve performance can be accommodated in the plant.
Should these efforts be unsuccessful, several alternatives are available to resolve these potential problems.
A list of potential problem areas and some possible alternatives.to be considered to address the undesirable valve performance is provided in Table III-5.
It should be noted that this list is not intended to be complete, but only to serve as a checklist or starting-point for the more detailed performance evaluations to be performed by the utilities, valve manufacturers and NSSS vendors.
III - 6
e Revision 1 2
Table III-6 provides a general summary of the safety valve test'results obtained.in the EPRI program.
Some considera-
_tions to be taken into account in evaluating off-normal valve. performance for.various conditions as noted in Table III-5 are discussed below:
Safetv Valves 1.
Performance with Steam Flow For virtually all safety valve / inlet piping.
combinations tested, ring settings were established in the EPRI tests which provided stable valve per-formance with steam inlet conditions.
- However, i
these ring-settings resulted in valve blowdown outside of normally accepted limits (i.e., greater than five percent).
Therefore, re-evaluation of selected NSS system overpressure transients should be performed by the NSSS vendors to show that in-f creased valve blowdown is acceptable.
Other poten-tial alternatives would be to utilize an alternative valve or shorten the valve inlet piping so that stable performance can be obtained with reduced
~
blowdown (i.e., near five percent).
2.
Performance with Subcooled Water Flow For some of the safety valves tested, the valves f-chattered with subcooled water inlet conditions.
III - 7 I
Revision 1 For these cases, if the fluid conditions for a specific plant include subcooled water, the utility /NSSS vendor could show that the subcooled j
water can be handled by other than safety valve actuation.
This could be accomplished by use of the PORVs to vent the flow (at a pressure less than the safety valve set pressure) or by op-erator termination of the transient.
Another possible solution is to utilize an alternative valve which performs in a stable manner with sub-cooled water or to modify the existing valve (e.g., using an assist device) to provide stable performance.
3.
Performance with Cold Loop Seals For the tests (with the spring-loaded valves) which utilized cold loop seals at the valve, a number of undesirable performance characteristics resulted, including large pressure oscillations in the upstream piping, delayed valve opening until loop seal clearing, and high pressures and loads in the discharge piping.
(Elevated temperature loop seal tests resulted in reduced piping loads.')
Possible alternritives to eliminate these undesirable per-formance features include draining the loop seal, heating the loop seal to near saturation or utilizing an alternative valve which provides better i
III - 8 L
F Rovision 1 s
performance with the loop seal.
However, before
~
a decision to drain or heat loop seals is made, careful consideration should be given to the potential consequences, e.g.,
increased potential for valve seat degradation and resulting steam /
hydrogen leakage.
Relief Valves Acceptable performance was obtained with most of the relief valves tested.
An off-normal result obtained was delayed valve closure for two of the relief valves (Dresser Electromatic and Target Rock) with fluid conditions that result from loop seal installations.
For plants which utilize these valves with loop seals, possible alternatives to consider include heating or draining of the loop seal, or utilizing an alternative valve which is less sensitive to the thermal transient.
However, before a decision to drain or heat loop seals is made, careful consideration should be given to the potential consequences of such operation as noted above.
d III - 9
Revision 1 TABLE III-l PLANT INFORMATION TO BE ASSEMBLIED BY UTILITY
-Following is a list of valve / piping information to be assembled by.the utility-for the evaluations:
1.-
Safety Valve Information Number of valves Manufacturer Type size (inlet, outlet, orifice)
Steam flow capacity (rated and maximum)
Design pressure and temperature Inlet flange rating Discharge flange rating Allowable applied load (should consider the applied load which resulted during testing)
Set pressure Accumulation (specified and existing, if available)
Blowdown (specified and existing, if available)
Ring settings (specified and existing, if available)
Original valve procurement specification original valve quality assurance package
~ Maintenance documentation package for valve 2.
Relief Valve Information Number of valves
' Manufacturer
+
Type-Size (inlet, outlet, orifice)
Steam flow capacity (actual)
Design pressure Design temperature Inlet flange rating Discharge flange rating Allowable applied load (should consider the applied loads which resulted during testing)
III - 10 L
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Ravicion 1 TABLE III-l (Cont'd)
Opening pressure (include all settings) i Closing pressure (include all settings)
Original valve procurement specification Original valve quality assurance package Maintenance documentation package for valve For air-operated valves:
Air supply system pressure and system schematic (tubing diameter, length, configuration, etc.)
For pilot-operated valves:
Electrical supply system voltage and current and wiring schematic Pilot vent path schematic (pipe diameter, length, configuration, etc.)
t 3.
Inlet Piping Information Design pressure Design temperature Configuration from pressurizer to valve (include an isometric
' drawing of the installation showing piping diameter, length and orientation)
Pressurizer nozzle configuration Loop seal (include volume and temperature of water in loop seal)
Piping supports (show location on isometric and list type and capacity of individual supnorts in a table)
Steady-state flow pressure drop (including velocity head) (1)
Acoustic wave pressure amplitudeTl) l f
4.
Discharge Piping Information Design pressure i
Design temperature l
Configuration (include an isometric drawing of the installation showing piping diameter, length and orientation)
Pressurizer relief tank design pressure Piping supports (show location on isometric and list type and capacity of individual supports in a table)
Note: (1)
See Appendix B, applies to safety valves only.
1:
t-III - 11 l
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Revision 1 TABLE III - 1 (Cont'd) i 5.
Valve Actuation Transient Information FSAR Transients Pressure (opening, peak, closing)
Temperature Pressurization rate at valve opening Maximum back pressure (2) (steam condition)
Fluid range (e.g.,
saturated steam, saturated water, steam to water transition, subcooled water)
Valves actuated (number and type)
III Cold overpressure Transients Pressure ranges (opening, peak, closing)
Corresponding temperature ranges Pressurization rate at valve opening II Maximum back pressure (steam condition)
Fluid range Valves actuated (number and type)
Extended High-PremFure Injection Transients Pressure range (opening, peak, closing)
Corresponding temperature range Initial pressurization rate l
Maximum back pressure (2) (steam condition)
Fluid range Valves actuated (number and type) i L
i Notes:
(1)
Applies to relief valves only (2)
See Appendix A l
l l
III - 12
Revision 1
~.
TABLE III-2 SAFETY VALVE PERFORMANCE
SUMMARY
SHEET A.
Parameters for Safety Valve Installation in Plant The follewing parameters are to be tabulated for the plant installation.
They are to be used to identify the tests with the representative valve / piping configuration most nearly corresponding to the plant configuration.
1.
Safety Valve Manufacturer
-Type Size 2.
Inlet Piping Piping length Piping diameter Dry or loop-seal 3.
Discharge Piping Back pressure range (for steam actuation) 4.
Inlet Piping Pressure Drop (Steam Actuation)
Steady-state Acoustic (after loop seal discharge) 5.
Applicable Test Numbers (Selected by comparing preceding information with EPRI test data) 6.
Valve Ring Settings Ring Settings i
l As-Installed Optimal Ring l
Upper Middle Lower l
l III - 13 l
Revision 1 i:
TABLE III-2 (Cont'd) l l
B.
Valve Performance Summary y
.The following valve performance characteristics are to be determined from the data for the applicable tests for both as-installed and optimal ring settings.
1.
Behavior Mode Fluid Condition Stable Chatter l Other Saturated steam Loop seal Transition-Water
- 650'F
- 550*F
- 400*F 2.
Performance Characteristics
- Flow Closing Fluid Opening Opening Capacity Pressure Condition Pressure (psia)
Time (sec)
(lb/sec)
(psia)
Saturated steam Loop seal i
Transition i
Water
- 650*F
- 550'F
- 400*F In addition, determine maximum back pressure for saturated steam condition.
III - 14
9 Revision 1 TABLE III-3 DEFINITION OF ACCEPTABLE PERFORMANCE FOR SAFE 2Y AND RELIEF VALVES AND
_IN,LET AND DISCHARGE PIPING Following is a definition of acceptable performance for safety and relief valves an-inlet and discharge piping:
A.
Safety Valves 1.
valves open and close in a stable manner.
(A minimum amount of valve chatter or flutter is permitted pro-vided no change in critical valve dimensions or wear of seating surfaces results.) See Note (1}.
2.
Valve performance characteristics are consistent with FSAR (or other design) overpressure analysis assumptions, including:
opening pressure opening time flow capacity closing pressure (i.e., blowdown)
B.
Relief Valves Valve performance characteristics are consistent with cold overpressurization analysis assumptions, including:
opening time flow capacity closing time i
l C.
Inlet Piping (see Note 2) l Piping stresses during valve discharge transient 1.
less than design stresses.
[
2.
Piping support loads less than design loads.
3.
Applied load on valve less than design load.
(The design loads should consider the applied loads which resulted during testing.)
It should be noted that when valve chatter occurrec curing non-(1) loop seal tests, the valve was assisted open to terminate the Therefore, the degree of valve internals degradation event.
during an actual in-plant event under similar conditions may be more severe than was observed in the testing.
Lomd combinations and allowable piping stresses and l
(2) support loads listed in Appendix E.
l III - 15 i
l
Revision 1 TABLE III-3 (Cont'd)
D.
Discharge Piping (see Note 1) 1.
Piping stresses during valve discharge transient less than design stresses.
2.
Piping support loads less than design loads.
~3.
Maximum pressure less than maximum acceptable valve back pressure.
4.
Applied load on valve less than design load.
which resulted during testing.)(The design loads should c
{
(-
}
r 3
(1)
Load combinations and allowable piping stresses and support loads listed in Appendix E.
b
Q."
Revision-1 TABLE III-4 RELIEF VALVE PERFORMANCE
SUMMARY
SHEET A.
Parameters for Relief Valve Installation in Plant The following parameters are to be tabulated for the plant installation.
They are to be used to identify the tests with the representative valve.
1.
Relief Valve Manufacturer Type Size 2.
Inlet Piping Dry or loop-seal 3.
Valve Operator Air supply system details or electrical voltage / current Other (size, force capacity) 4.
Applicable Test Numbers III - 17
Rsvision 1 TABLE III-4 (Cont ' d )
B.
Valve Performance Summary The following valve performance characteristics are to be' determined from the data for the applicable tests.
Fluid Opening Flow Condition Time (sec)
Capacity (1b/sec)
Closine Time (sec)
Saturated steam Water Seal Transition
- Steam to water
- Nitrogen to water Water (at high pressure set-point)
- Maximum temperature
- Minimum temperature Water (at low pressure set-point)
- Maximum-temperature
- Minimum temperature III - 18
Revision 1 C.
TABLE III-5 LIST OF POTENTIAL PROBLEM AREAS AND
[
POSSIBLE ALTERNATIVES TO ADDRESS UNDES1RABLE VALVE PERFORMANCE Potential Problem Areas Possible Alternative Safety Valves and Associated Pipinc
- 1. Valve blowdown required Re-analyze selected NSSS system to provide stable valve overpressure transients to show performance for steam flow that increased valve blowdown is is not within FSAR/ Tech acceptable from the standpoint of Spec limits, plant operation considerations.
(Noto, since all plants are de-signed to accommodate losses of reactor coolant resulting from a range of possible size openings in the reactor coolant system, it is apparent that increased valve blowdown is not a safety concern.)
Utilize alternative valve which provides stable performance with smaller blowdown.
Relocate valve closer to pressur-izer to allow stable performance to be obtained with reduced blowdown.
- 2. Valve chatters with subcooled Show that subcooled water condi-water flow conditions and tions can be handled by other i
blowdown cannot be adjusted than safety valve actuation,
~
to provide stable valve e.g., operator action or use of performance PORVs.
I:
Utilize alternative valve which performs in a stable manner with subcooled water, (e.g.,
Framatome/ Crosby 6M6, or Target Rock 69C) or utilize an auxiliary lift device with the existing valve.
F III - 19
Pevision 1 4:
TABLE III-5 (Cont'd)
Possible Alternative Potential Problem Area
- 3. With cold loop seal arrangement, Provide a drain at low point
. valve provides unacceptable per-in loop seal piping back to water accumulation (prevent the pressurizer to formance,'e.g.: _
l).
pressure oscillations (water-hammer) in upstream piping Provide heaters to increase temperature of loop seal delayed valve opening until water to near saturatiop) loop seal clears (approximately 650*F).
high pressures and loads in Utilize alternative valve discharge piping which provides better performance with loop seal.
Relief Valves Provide a drain at low point With cold loop seal arrangement, in loop seal pipine to prevent valve closure following discharge water accumulation (l).
is delayed Provide heaters to increase temperature of loop seal water. (1)
Utilize. alternative valve which is less sensitive to the thermal transient.
Before a decision to drain or heat the loop seals NOTE:
(1) is made, careful consideration should be given to the potential for valve seat degradation and result-ing steam / hydrogen leakage.
III - 20
Revision 1
't TABLE III-6 EPRI PWR SAFETY AND REllEF VALVE TEST PROGRAM SAFETY VALVE TEST RESULTS
SUMMARY
(1)
(CRITERIA: STABLE PERFORMANCE /NO CHATTER)
TESTED VALVES INLET FLUID CONDITIONS STEAM LOOP SEAL TRANSITION WATER 6S0 F 550 F 400cp 0
0 e
DRESSER 31739A YES N/A YES YES YES YEs P)
SHORT INLET LONG INLET YES YES (4)
YES YES NO e
DPISSER 31709NA YES N/A YES YES YES NO
-SHORT INLET LONG INLET (3)
NO e
CROSBY 3X6 YES N/A YES YES NO SHORT-INLET LONG INLET' YES YES NO e
CROSBY 6M6 YES YES YES YES NO LONG INLET
.e TARGET ROCK 69C YES YES YES YES( 6 )
YES ( 6 )
YES(6)
LONG INLET e
CROSBY 6N8 YES N/A YES YES NO
.LONG INLET s
FRAMATOME/ CROSBY YES YES YES YES YES YE!
6M6 LONG INLET summary is for valve performance after reference test ring NOTES:
The settings had been established and does not generally reflect (1) ex-pected performance with current in-plant ring settings.
(2)
Indicates the condition is not applicable to the valve / piping combination tested.
Plants which utilized this valve / piping combination have been (3) modified and now have a short inlet.
l (4)
Chatter observed on loop seal portion of test.
The valve had a limited lift and did not relieve the transient.
(5)
(6)
Observed inlet pressure fluctuations indicated possible valve flutter.
III - 21
Revision 1 IV.
SUGGESTED FORMAT FOR JULY 1, 1982 PLANT-SPECIFIC SUBMITTAL A suggested format for the July 1, 1982 plant-specific submittal to the NRC is provided in the following.
It should be noted that the submittal outline is provided only as a general guideline for utility consideration and it is recognized that more or less information may need to be included in a particular plant-specific submittal.
I.
DESCRIPTION OF SAFETY AND RELIEF VALVE INSTALLATION This section should provide a summary description of the overall valve installation.
In addition, this section should provide a list of key plant parameters as listed in Table IV-1, including:
-Safety valve parameters Relief valve parameters Inlet piping parameters Valve actuation transient parameters II.
RESULTS OF PLANT-SPECIFIC PERFORMANCE EVALUATIONS A.
Safety and Relief Valve Performance This section should discuss the following:
1.
Evaluation of pertinent test results and identification of conditions which could result in unacceptable valve performance.
2.
Identification of modifications selected for implementation to provide acceptable performance.
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Revision 1 B.
Inlet and Discharge Piping Adecuacy This section should discuss:
1.
Evaluation of stresses and support loads in inlet and discharge piping and identification of any overstressed piping or overloaded supports.
2.
Identification of modifications required to provide acceptable stresses and loads in piping and supports.
III.
CONCLUSIONS IV.
REFERENCES This section should include a listing of all references utilized in the evaluations,' including:
A.
Safety and Relief Valve Test Reports b.
Valve Selection / Justification Report C..
Plant and Test Condition Justification Reports D.
Discharge Piping Load Model Report V.
APPENDICE$
The following appendices should be included:
A..
Summary of report by valve manufacturers which justi-fies the acceptability of valves or the modification (s) selected for implementation.
B.
Summary of report by NSSS vendor wntch justifies the
[
acceptability of the existing system or modification (s) selected for implementation.
IV - 2
Rsvinion 1 C.
Summary results of calculations of inlet and discharge piping loads and stresses.
D.
Schedule for evaluation and implementation of modifications (if modifications are required).
9 3
IV - 3
Revision 1 TABLE IV-1 LIST OF KEY PLANT PARAMETERS 1.
Safety Valve Information Valve Parameters-Number of valves Manufacturer Type Size (inlet, outlet orifice)
Rated capacity (steam)
Inlet Pipine Parameters Diameter Length Type (dry, loop seal /terperature)
Actuation Transient Parameters Fluid range (e.g., saturated steam, saturated water, subcooled water,.etc.)
Maximum back pressure (steam condition)
I
-2..
Relief Valve Information Valve Parameters Number of valves Manufacturer Type Size (inlet, outlet, orifice)
Capacity (steam)
IV - 4
t' Revision 1 4-TABLE IV-1 (Cont'd)
Inlet Piping Parameters Type - (dry, loop seal / temperature)
Actuation Transient Parameters Fluid range (e.g., saturated steam, saturated water, subcooled water, etc.)
Maximum back pressure (steam condition) 1 e
IV - 5
Ravision 1 V.
REFERENCES Following is a list of reports issued by EPRI to document the Also noted results of the safety and relief valve test program.
are the draft and final ~ publication dates of the report and the f
' data when the report will'be submitted to the NRC via the PWR 2
utilities.
Report Date Draft Final Submitted to NRC EPRI Report 1..
Safety and Relief Valve Test 3/1/82
'4/1/82 4/1/82 Report 2.
Valve Selection / Justification 9/81 12/81 4/1/82 Report 3.
Test Condition Justification 3/5/82 4/1/82 4/1/82 Report 4.-
B&W Plant Fluid Condition 10/8/81 3/17/82 4/1/82 Justification Report 5.
CE Plant Fluid Condition 11/18/81 3/10/82 4/1/82 Justification Report 6.
W Plant Fluid Condition 10/8/81 1/29/82 4/1/82 Justification Report 7.
Application of RELAPS/ MOD 1 for Calculation of Safety and Relief Valve Discharge Piping Hydrodynamic Loads'(includes Discharge Piping Datal-3/5/82 4/1/82 4/1/82 8.
Marshall Relief Valve 8/81 10/81 N/A Test Report 9.
Wyle Phase II Relief 9/81 12/81 N/A Valve Test Report 10.
Wyle Phase III Relief 3/9/82 4/1/82 N/A valve Test Report 11.
CE Safety Valve Test Report 6/1/82 7/1/82 N/A N/A Not Applicable.
These reports contain supplementary information.
r' n--
A R';vician 1 I
a
)
z i
b VI.
APPENDICES i
i-l' t
i i
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"v
Revision 1 APPENDIX A PROCEDURE FOR CALCULATION OF VALVE BACK PRESSURE
,u Rovision 1
'i '
i
-A.
Purpose The purpose of this appendix is to provide a suggested procedure and guidelines for the calculation of safety and relief valve backpressure for the plant.
This backpressure is to be compared with the test backpressure as discussed in Appendix D.
B.
Discussion Because of the sensitivity to back pressure exhibited by the safety valves in the EPRI test program, it is recom-mended that the plant back pressure be calculated on a l
realistic, rather than conservative, basis.
Therefore, it is suggested that a hydraulic code such as RELAP or
=
similar method be utilized.
In this regard, EPRI
_ ~has funded / developed a steady-flow hydraulic code specifically for determining valve backpressures.
Further-information regarding this code can be obtained from EPRI.
lit is suggested that back pressure calculations be performed assuming simultaneous actuation of either all safety valves or all relief valves on steam.
Also, use the maximum valve' flow rates as determined by the valve manufacturer.
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Revision 1
-~ l The computed steam backpressures are to be compared to those developed during EPRI steam tests to assess applicability.
EPRI liquid testing was performed with the same discharge piping backpressure orifice as was utilized during a specified steam test.
The backpressures developed during the liquid tests correspond to those expected in a plant having the same " steam" backpressure as was developed during the specified steam test.
Therefore, if the steam backpressure developed exceeds the expected in-plant steam backpressure, the corresponding liquid backpressures de-veloped will exceed those expected in the plant under
.similar conditions.
A-2
7-.
R3 vision 1 I, h[
~
, r.
APPENDIX B PROCEDURE FOR CA',CULATION OF INLET PIPING PRESSURE EFFECTS
Revision 1
!5 A.
Purpose 7
The purpose of this appendix is to provide a procedure for determining the' inlet piping pressure drop associated with spring-loaded safety valve opening for the plant safety valve installation.
This plant pressure drop is to be compared with the test pressure drop as discussed in Appendix D.
3 B.
Discussion
'The procedure described below is only applicable to high-quality steam-filled inlet piping installations which have a constant flow area.
The method consists of calculating
'the inlet piping pressure drop due to flow pressure drop and acoustic wave propagation.
1.
Inlet Piping Flow Pressure Drop (SPF.)
The flow pressure drop is given by, (k+1+fL)g2 5
=
29 #A c
- where, l
expansion or contraction loss coefficient.
k
=
(dimensionless) friction factor (see Reference 1) (dimensionless) f
=
L piping equivalent length / diameter considering 5
effects of fittings and friction (see Reference 1 for pertinent data) (dimensionless) maximum valve flow rate for steam (as established A
=
by the safety valve manufacturer) (lb/sec) 2 9e gravitational constant (32.2 lb-ft/lb-sec )
steamgensityatnominalvalvesetpressure o
=
(1b/ft )
l 2
inlet piping flow area (ft )
l A
=
l i
Revision 1 2.
Acoustic Wave Amplitude (aPgg) t The acoustic wave amplitude is calculated based on information in Reference 2.
There are two situations
~
~
to consider:
- If T
< 2 L/a, gp aM AP y gg g
c
- If T
>2L/a, op O NI ge Top
- where, a = steam sonic velocity at nominal valve set pressure (ft/sec)
L = inlet piping length (f t)
T
= valve opening time for steam inlet conditions op as established from the EPRI testing effort is 10 msec for the Crosby safety valves and 15 msec for the Dresser safety valves.
The other variables are the same as defined in the
(
previous section.
3.
Plant-Specific Pressure Drop The plant-specific pressure drop associated with valve opening is equal to the sum of the friction pressure drop l
(AP ) and the acoustic wave amplitude (APgg) as determined F
above.
For certain test valves, valve reopening and/or chatter was observed on valve closure.
For similar valve / installations, the pressure rise associated with valve closure may have to be evaluated.
I C.
References 1.
Flow of Fluids through Valves, Fittings and Pipe, Crane Co., Technical Paper No. 410, 1981.
2.
Waterhanner Analysis, John Parmakian, Dover Publications, Inc., 1963.
7 R
l Rovision 1 D.
Sample Problem Fo, lowing is a sample calculation of plant-specific pres-l sure drop for an assumed safety valve / inlet piping configuration, i
1.
Flow Pressure Drop An isometric of the assumed inlet piping configuration is provided in Figure B-1.
The flow pressure drop is 6.
given by, (k+1+fL)A2 6
APy y
=
2ge:A
- where, 0.5(1)*(sudden contraction at pressurizer k
=
nozzle)
III
.016 f
=
b jf
'+ 6 x 30(1) + 2 x 16(1) = 289.8
=
D 3 (2) (saturated steam at 2500 psia) 7.65 lb/ft c
=
A
.=
0.147 ft2 345,000 lb/hr 95.8 lb/sec
=
A
=
3600 sec/hr The flow pressure drop is, 2
(0.5 + 1 +.016 x 289.8) x 95.8 3p 2
64.4 x 7.65 x.147 x 144 36 psi APy
=
- Numbers in parentheses denote references listed at the end of this sample problem.
B-3
Revision 1 8
7'10" 6'10" SAFETY VALVE PRESSURIZER 2'1" 6'10" NOZZLE 2'3" 4'2" 3'7" PRESSURIZER
- TOTAL PIPE LENGTH = 33'7"
- PIPE DIAMETER = 6" SCH. 160 (5.189" INSIDE DIAM.)
- FITTINGS.
6, 90* ELBONS 2, 45* ELBOWS
-CROSBY 4M16 SAFETY VALVE
~
345,000 lb/hr RATED CAPACITY
.010 SEC OPENING TIME SAFETY VALVE INLET PIPING CONFIGURATION FIGURE B-1 9-4
Revision 1 3:
2.
Acoustic Wave Amplitude For the configuration in Figure B-1, the parameters
- are,
.010 sec T
=
p 2L 2 x 33.6 ft
.052 sec
=
1300 ft/sec(3)
<fb, Since Top a$
APAW "
g{A 1300 x 95.8 3~p AW 32.2.x.147 x 144 183 psi SPgg =
3.
Plant-Specific Pressure Drop The plant-specific inlet piping pressure drop is given by, LPp + aP g AP
=
A 36
+ 18 3 = 219 psi AP
=
4.
References (1)
Flow of Fluids through Valves, Fittings and Pipe, Crane Co., Technical Paper No. 410, 1981.
(2)
ASME Steam Tables, 1967.
(3)
"A Pressure Pulse Model for Two-Phase Critical Flow and Sonic Velocity," ASME 68-WA/HT-8.
B-5
a 5
fi._ _ '
E.
Test Valve / Inlet Pipe Configuration Inlet Piging Pressure Drop Following are Tables B.1 through B.6 entitled " Safety Valve Description and Inlet Piping Configuration".
These tables provide a description =of the tested safety valves and the inlet piping configurations on which the valves were mounted.
The information contained in these tables are the same as the information contained in Tables 3.1.1.a through 3. 6.1.a of Reference 1 (see Sec-tion V) with the addition of the calculated transient pressure drop for each test inlet pipe configuration.
4 The transient pressure drops listed in each table are the
~
calculated upstream pressure drops associated with valve opening for each test valve / inlet pipe configuration.
Opening (Pop) times used to calculate the pressure drop are defined in footnote (1) of the tables.
These opening times were established based on the opening times measured in the EPRI/PWR Safety and Relief Valve Test Program.
The test data indicated that an opening time of 15ms for all of the Dresser safety valves tested and an opening time of i
10ms for all of the Crosby safety valves tested were typi-cal of the fastest opening times measured.
B-6 I.
Li -
Since the test valves were selected to represent all participating PWR plant safety valve designs and the data indicated opsning times which were consistent across the test valves, it is suggested that the opening times defined for each manufacturer's safety valve tested be used for the valve manufacturer's designs which were not tested.
I l
l l
t '
l B-7
~
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iA
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EPRI/CE SAFETY. VALVE TEST PROGRAM TABLE B.1 SAFETY VALVE DESCRIPTICN AND INLET PIPING CONFIGURATION' DRESSER 31739A SAFETY VALVE Valve Description Inlet Piping Configuration '
"D" Length, in.
I.D., in.
Manufacturer Dresser Industries Nozzle 17 6.813 Type Spring loaded Safety Valve Model No.
31739 A Venturi 38 6.813 Serial No.
BN-04372 Drawing No.
4CP-2432 Rev. 9 Pipe 11 6.813 Body Size (inlet / outlet) 2h in./
6 in.
Reducer 6
6.813/3.152 Bore Area 2.545 in.2 Orifice Designation 3
Loop Seal Straight 60 3.152 as Design Set Point Pressure 2500 psig Gends 4-900 6 in. radius Design Blowdown 5
percent Reducer 4
3.152/2.125
=
Rated Flow 297845 lb/hr. Rated Lift 0.45 in.
Inlet Flange 6
2.125 Internals Type:
Not applicable Transient Pressure Drop (1) 454 psi Ring Setting Reference Position:
Inlet Piping Configuration "C"
The ring setting positions refer to the number of Length, in.
I.D., In.
notches relative to the following surfaces; Nozzle 17 6.813 Upper Ring - top holes in the guide Middle Ring-seat plane Venturi 38 6.813 Lower Ring - seat plane Pipe 11 6.813 (1) This is the calculated transient upstream Reducer 10 6.813/2.125 pressure drop associated with valve opening for this valve / inlet piping Pipe Not applicable configuration. The pressure drop was calculated based on an opening time of Inlet Flange 6
2.125 15 msec.
Transient Pressure Drop (1) 54 psi
E
~
EPRI/CE SAFETY VALVE TEST PROGRAM-TABLE 8.2 SAFETY VALVE DESCRIPTION AND INLET PIPING CONFIGURATION DRES$tR 31709NA l
Valve Description.
Inlet Piping Configuration "A"
Length, in.
I.D., in.
4 Manufacturer Dresser Industries Nozzle 17 6.813 l
Type
. Spring Loaded Safety Valve Model No.
31709A Venturi 38 6.813 i
Serial No.
8007681 j
Drawing No.
4CP-2332 Rev 11 Pipe 6
6.813 Body Size (inlet / outlet) 6 in./
8 in.
Reducer 6
6.813/4.897 Bore Area 4.34 in.2 Orifice Designation N
Loop Seal Straight 48 4.897 y
Design Set Point Pressure 2500 psig Bends 2 Bends'1800, 9" radius 2
Design 810wdown 5
percent Reducer not applicable Rated Flow 5079181b/hr. Rated Lift 0.588 in.
Inlet Flange 11 4.897 Transient Pressure Drop (1) NOT AVAILABLE Internals Type:
not appilcable i
Inlet Piping Configuration "B"
l Length, in.
I.D., in.
j Ring Setting Reference Position:
The ring setting positions refer to the ninnber of 17 6.813 notches relative to the following surfaces; Nozzle 38 6.813 Upper Ring - top holes in the guide Venturi l
Middle Ring-seat plane lower Rinq - seat plane Pipe 6
6.813 (1) This is the calculated transient upstream Reducer 6
6.813/4.897 pressure drop associated with valve opening j
for this valve / inlet piping configuration.
Pipe not applicable The pressure drop was calculated based on j
an opening time of 15 msec.
Inlet Flange 11 4.897 l
Transient Pressure Drop (1).E& ps i
EPRl/CE SAFETY VALVE TEST PROGRAM TABLE B.3 SAFETY VALVE DESCRIPTION AND INLET PIPING CONFIGURATION FOR Tile CROSBY llB-BP-86 3K6 (STEAM INTERNALS) l Valve Description Inlet Piping Configuration "F"
Length, in.
I.D., in.
Manufacturer Crosby Valve and Gage Nozzle 17 6.813 Type Spring Loaded Safety Model No.
IIB-BP-86 3K6 Venturi 38 6.813 Serial No.
None Drawing No.
SK-3658-V Pipe 6
6.813 j
BodySize(inlet / outlet) 3 in./
6 in.
Reducer 6
6.813 i
Bore Area 1.841 in.2 j
Orifice Designation K
Loop Seal Straight 54 3.152
]
in Design Set Point Pressure 2485 psig
' Bends 4-900 6 inches radius
]
g Design Blowdown 5
Percent Reducer 4
3.152/2.624 J
j Rated Flow 212.182 lb/hr. Rated Lift 0.382 in.
Inlet Flange 7
2.624 Internals Type:
Steam Transient Pressure Drop (1) 321 nst Ring Setting Reference Position:
Inlet Piping Configuration "E"
Length, in.
I.D., in.
l The ring setting position refers to the number of notches relat'ive to the bottom of the ring disc.
Nozzle 17 6.813 2
(1) This is the calculated transient upstrean Venturi 38 6.813 pressure drop associated with valve opening for this valve / inlet piping configuration.
pipe 6
6.813 The pressure drop was calculated based on 1
an opening time of 10 msec.
Reducer 10 6.813/2.624 4
2.624 Pipe 7
2.624
]
Inlet Flange i
Transient Pressure Drop (1) 56 psi i
i i
EPRI/CE SAFETY VALVE TEST PROGRAM TABLE B.4 SAFETY VALVE DESCRIPTION AND INLET PIPING CONFIGURATION FOR THE. CROSBY HB-BP-86 3K6 (LOOP SEAL IrlTERflALS)
Valve Description Inlet Piping Configuration "F"
I Length, in.-
1.D., in.
Manufacturer Crosby Valve and Gage Nozzle 17 6.813 l
J Type Spring Loaded Safety Model No.
HB-BP-86 3K6 Venturi 38 6.813 Serial No.
None j
Drawing No.
SK-3658-V Pipe 6
6.813 Body Size (inlet / outlet) 3 in./
6 in.
Reducer 6
6.813/3.152 Bore Area 1.841 in.2 l
Orifice Designation K
Loop Seal Straight 54 3.152 Design Set Point Pressure 2485 psig Bends 4-900 6 inches radius 8
Design Blowdown 5
percent Reducer 4
3.152/2.624 M
0.382 Rated Flow 212,182 lb/hr. Rated lift in.
Inlet Flange 7
2.624 Internals Type:
Loop Seal Transient Pressure Drop (1) 3gj_pyg l
Inlet Piping Configuration _
"E" i
Ring Setting Reference Posttion:
tength, in.
1.D., in.
The reported measurements are relative to i
l the bottom of the disc ring.
Nozzle 17 6.813 I
38 6.813 l
(1) This is the calculated transient upstream Venturi j
pressure drop associated with valve opening 6
6 813 for this valve / inlet piping configuration.
Pipe i
i The pressure drop was calculated based on 10 6.813/2.624 l
an opening time of 10 msec.
Reducer 4
2.624 pipe
.624 Inlet flange Transient Pressure Drop (1) 56 psi
- 6 I
EPRl/CE SAFETY VALVE TEST PROGRAM TABLE B.E-3 SAFETY VALVE DESCRIPTION AND INLET PIPING CONFIGURATION FOR THE CROSBY HB-BP-86 6:16 (LOOP SEAL INTERNALS)
Valve Description Inlet Piping Configuration "G"
Tength',in.
I.D., in.
l Manufacturer Crosby Valve and Cage Company Nozzle 17 6.813 4
l Type Spring Loaded Safety Valve l
Model No.
HB-BP-86 6M6 Venturi 38 6.813 i
Serial No.
N56%4-00-0086 Drawing No.
Crosby DS-C-56964 Rev. C Pipe 13 6.813-tn l
Body Size (inlet / outlet) 6 in./
6 in.
Reducer 6
6.813/4.897 Bore Area 3.644 in.2 Orifice Designation M
Loop Seal Straight 48 4.897 Bends 2-1800 9 in. radius Design Set Point Pressure 2485 psig Design Blowdown 5
percent f
Rated Flow 420,006 lb/hr. Rated Lift 0.538 in.
Internals Type: Loop Seal ducer Not Applicable Ring Setting Reference Position Inlet Flange 10 4.897 The ring setting position refers to the number of notches relative to the bottom of the disc ring.
Iransient Pressure Drop (1) 251 ngi (1) This is the calculated transient upstream pressure drop associated with valve opening for this 1
I l
valve / inlet piping configuration.
The pressure drop was calculated based on an opening time of 10 msec.
l
EPRl/CE SAFETY VALVE TEST PROGRAM TABLE B.6
.'t SAFETY VALVE DESCRIPTION AND INLET PIPING CONFIGURATION FOR THE CROSBY HB-RP-86 6N8 (STEAM INTERNALS)
Valve Description inlet Piping Configuration "H"
Length, in.
I.D., in.
i Manufacturer Crosby Valve and Gage Company Type Spring Loaded Safety Valve Nozzle 17 6.813 Model No.
HB-BP-86 6N8 Serial No.
N61894-00-0006 Venturi Not Appilcable Drawing No.
Crosby DSC-61894 Rev. D Pipe 9
6.813 Body Size (4.381 inlet / outlet) 6 in./
8 in.
Bore Area in.2 Reducer 6
6.813/5.189 I
Orifice Designation N
Pipe 76 5.189 Design Set Point Pressure pans psig Inlet Flange 7
5.189
[
Design Blowdown 5
oercent w
Rated Flow 504.962 lb/hr. Rated lift n son _in, j
Internals Type:
Steam Transient Pressure Drop (1) 270 psi j
Ring Setting Reference Position:
j The ring setting position refers to the number of notches relative to the bottom i
of the disc ring.
i l
I (1) This is the calculated transient upstream pressure drop associated with valve opening for this valve / inlet piping configuration.
The pressure drop was calculated based on 4
an opening time of 10 msec.
3 i
i i
1 1
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Revision 1 APPENDIX C PROCEDURE FOR VERIFICATION OF ALTERhATIVE METHODS TO BE USED IN EVALUATION OF PIPING / SUPPORT ADEQUACY
Revision 1 As discussed in Section II of this guide, the utility may elect to use an alternative method to perform the evaluation of piping / support adequacy.
In this event, it is recommended that th's adequacy of the alternative method be verified by comparison with the EPRI test data provided in Reference 7 (see Section V).
This can be accomplished by one of the following approaches:
By. direct comparison between the analytical method pre-dictions and the data measured in the CE Facility tests.
By cpmparison between the hydraulic forcing function determined by the alternative method with the forcing function determined by the EPRI-provided code (RELAP5).
Revision 1 4
APPENDIX D PROCEDURE FOR ASSESSMENT OF APPLICABILITY OF SPECIFIC EPRI i
SAFETY VALVE TESTS
Revision 1 A.
Purpose The purpose of this appendix is to provide a procedure for use by the valve manufacturers (or utilities) in assessing the applicability of specific EPRI tests to plant safety valve installations.
This procedure is based on directly using test results from the EPRI program in the plant-specific evaluation.
Thus, the key is to establish that one or more of the represen-tative valve / piping configurations tested by EPRI closely matches the plant installation.
It is expected this approach will be useful for virtually all the plant evaluations.
B.
Discussion The results of the EPRI safety valve tests indicate that there are a number of key parameters which effec-tively control the response of the safety valves.
These parameters are:
-Valve ring settings (for spring-loaded safety valves only)
Discharge piping backpressure Inlet piping pressure effects associated with valve opening (for spring-loaded safety valves only)
f I-Revision 1 i
l Inlet fluid conditions (e.g., saturated steam, saturated water, subcooled water).
A suggested procedure for assessing the applicLbility of specific EPRI tests to various plant installations is provided in Table D-1.
This procedure involves following four steps to determine the applicability of a particular test or test series.
Note that if tests are not found to be directly applicable to the plant valve evaluation, the EPRI test data base combined with other existing test data and/or analysis would have te be used to establish the expected valve performance in the olant.
C.
Sample Evaluation Table D-2 provides the results of a sample test appli-cability assessment for a Dresser safety valve, Model 31759A using test data for Dresser safety valve Models 31739A and 31709NA.
This case is the more complex of the two options identified in Table D-1:
a valve not directly tested, but one for which the valve manufacturer can identify ring settings which provide i
similar performance.
Further, the evaluation requires comparison to two different representative valve / piping configuration tests to assess the expected performance of the valve.
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D-2 s
Revision 1 The results of the sample evaluation are discussed in
'the following:
Test 1 -- The test is directly applicable because o
the valve ring settings, plant backpressure, inlet piping pressure and fluid condition requirements specified in Table D-1 are satisfied.
o Test 2 -- The test is directly applicable because the valve ring settings, plant backprossure, inlet piping pressure and fluid condition requirements specified in Table D-1 are satisfied.
o Test 3 -- This test is not directly applicable because the plant backpressure is greater than the test backpressure.
I o
Test 4 -- This test is not directly applicable because the plant inlet piping pressure drop is greater than the test inlet piping pressure drop.
I D-3
Revision 1
.e 4
Test 5 -- Tnis test is not directly applicable because the plant valve ring settings do not correspond to those specified by the valve manufacturer to provide similar performance to the test valve.
Test 6 -" This te=t is directly acclicable becmtse the valve ring settings, plant backpressure, inlet piping precrure and fluid condition requirements speci-fied in Table D-1 are satisfied, In this sample assessment, the Dresser Model 31759A safety valve is determined to provide acceptable performance for steam inlet conditions (at a plant backpressure of 400 psia and an inlet piping pressure drop of 150 psi), and unacceptable performance for 550*F water inlet conditions.
Based on the six tests listed in Table D-2, no direct indication can be obtained of the safety valve performance for the 650*F and 450*F water inlet conditions.
However, frou a l
review of the safety valve test results summarized in l
Table III-6 of this guide, it is apparent that valve performance would be acceptable for 650*F water and unacceptable for 450*F water.
I i
D-4 l
Revision 1 TABLE D-1 PROCEDURE FOR ASSESSMENT OF APPLICABILITY OF SPECIFIC EPPI TESTS
- STEP A -- VALVE RING SETTINGS For Valves Tested in the EPRI Programt 1.
Are the ring settings for the plant valve the same as for tha tested valve?
2.
If the answer to the above question is yes, proceed to Step B.
3.
If the answer to the above question is no, the test is not directly applicable to the plant evaluation.
For Valves not Tested in the EPRI Programt 1.
Is the plant valve represented by a test valve per Reference 2 (see Section V)?
2.
Do the ring settings for the plant valve correspond to those specified by the valve manufacturer to obtain similar performance as observed for the test valve?
3.
If the answers to Questions 1 and 2 are both yes, proceed to Step B.
4-If the answer to either Question 1 or 2 is no, the is not directly applicable to the plant test evaluation.
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I D-5 i
_ ~ _.
Revision 1
.. a TABLE D-1 Cont'd
- STEP B -- DISCHARGE PIPING BACKPRESSURE (See Appendix A for the procedure f o.
calculating plant backpressure) 1.
Is the plant backpressure less than the backpressure in the test?
(This comparison should be made for steam discharge condition as discussed in Appendix A.)
2.
If the answer to the above question is yes, proceed to Step C.
-3.
If the answer to the above question is no, the test is not directly applicable to the plant evaluation.
(How-ever, if unacceptable valve performance was observed in the test, it is highly probable that unacceptable valve performance would also result at the plant backpressure condition.)
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i D-6 f
Revision 1 7
TABLE D-1 (Cont'd)
- STEP C -- INLET PIPING PRESSURE EFFECTS *
(See Appendix B for the procedure of calculating plant inlet piping pressure effects) 1.
Is the plant inlet piping pressure drop due to valve opening less than the corresponding value for the test?
(This comparison should be made for the steam discharge condition as discussed in Appendix B.)
2.
If the enswer to the above question is yes, proceed to Step D.
3.
If the answer to the above question is no, the test is not directly applicable to the plant evaluation.
(However, if unacceptable valve perforamnce was observed in the test, it is also highly probable that unacceptable valve perfor-mance would also result at the plant inlet piping pressure drop condition. )
The procedure outlined in this step should only be used for those plant installations which have the same or smaller valve nozzle and the same inlet nominal piping diameter as those tested.
For other cases, a different evaluation method may be required.
In this regard, EPP!
has funded / developed an analytical method that can be used for these evaluations.
Further information regarding this method can be obtained from EPEI.
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l l
l D-7
r Revision 1
~
TABLE D-1 (Cont'd)
STEP D -- INLFT FLUID CONDITION 1.
Is the inlet fluid condition for the plant (see list in Table II-l of.this guide) the same as the inlet fluid condition for'the test?
- 2.
If the answer to the above question is yes, the applicability' assessment is complete and the test is determined to be applicable to the plant evaluation.
3.
If the answer to the above question is no, the test is not directly applicable to the plant evaluation.
i D-8
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TABLE D-2 SAMPLE TEST APPllEABILITY ASSESSENTS ***
i.
PLANT A TEST 1 TEST 2 TEST 3 TEST 81 TEST 5 TEST 6 VALVE MAKE/MODEL DRESSER DR31739A DR31709NA DR31739A. DR31739A DR31739A DR31739A 31759A RING SETTINGS
+X,-Y,+Z*
4818, 8 0, 450,-27,
+818, 810, 4:18, i 0,
+100,-30,
+818, 810, 1
+11 410
+11
+11
-10
+11 CACKPRESSURF
~
300**
(S1EM) (PSIG) 8:00 650 600 300 650 650 INLET PIPING PRESSURE UROP (PSI) 150 250 300 250 40 250 250 INLET
- STEAM, FLUID EOND.
WATER STEAM STEM STEAM STEAM.
STEM WATER 8
(550 F)
(650,550-,
ii00 F)
OBSERVED PERFORMANCE N/A GOOD GOOD GOOD GOOD BAD.
BAD 7g TEST APPLICA3tE?
N/A YES YES No NO NO YES e
RING SETTINGS RECOPO4 ENDED BY VALVE VENDOR BASED ON PEVIEW OF EPRI TEST DATA SIMILAR PERFORMANCE TO THE 31739A AND THE 31709NA TEST VALVES.
SAME DISCHARGE PIPE ORIFICE USED WilICH RESUtTED IN A 650 PSIG BP DN STEAM VALUES SHOWN FOR ILLUSTRATION ONLY, ACTUAL VA;.9ES SliollLD BE OBTAINED FROM REFERENCE 1 (SEE SEC THE INLET PIPING PRESSURE DROP INFORMATION IS CONTAINED IN APPENDIX B (PARAGRAPH E 1
FE n-
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- Revision 1 t
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APPENDIX E LOAD COMBINATIONS AND ACCEPTANCE CRITERIA FOR THE SAFTTY AND RELIEF VALVE PIPING EVALUATION E
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1 Revision 1 Y
.A.
' Purpose The purpose of this appendix is to provide suggested load combinations and acceptance criteria for the pressurizer safety and relief valve piping system.
During'the course of the EPRI valve program, an ad hoc group was established to help insure analysis consistency regarding discharge piping.
The recommended load combinations and
. acceptance criteria provided in the following section were developed by this group and are being suppli'd to you for your consideration.
B.
Discussion The recommended load combinations and acceptance criteria for the precsurizer safety and relief valve piping system and supports are shown in Tables 1, 2A and 2B.
Tables 2A and 2B are for the discharge, or downstream, piping and supports.
Table 2A applies to the portion for which seismic requirements apply.
There are two possible approaches to this requirement.
The entire downstream portion may be seismically designed, in which case, only Table 2A need be used.
If only a portion of the down-stream system is seismically designed (e.g., to the first downstream anchor, or enough supports and piping to ffectively isolate the seismic and non-seismic portions), then Table 2A would apply for that portion, while Table 2B would apply to the rest of the downstream system.
(-
R3 vision 1 For the seismically designed downstream piping and supports, less restrictive allowables are suggested.
Since satisfac-tion of allowable. valve loading is part of the acceptance
. criteria, this would appear to be acceptable.
For the non-seismically designed portion of the downstream
- piping, it is recommended that the pipe support system be seismically designed to assure overall structural integrity of the system.
It is suggested that Service Level D limits be-applied for all pipe support load combinations contain-t ing OBE or SSE.
e E-2
m TABt.E 1 LOAD COMBINATIONS AND ACCEPTANCE CRITERI A FOR PRESSURIZER SAFijTY AND RELIEF VALVE PIPING AND SUPPORTS - CLASS ILPORTION Service Stress Plant / System l
Combination Operating Condition I,oad Combination i.imi t A
1 Normal N
B N + OBE + SOT 2
Upset g
4 N + SOT 3
Emergency E
D 4
Faulted N + MS/FWPB or DBPB
+ SSE + SOTp D
g 5
^
Plants without an FSAR may use the proposed criteria contained in Tables 1-3.
Plants with an FSAR may use their original design basis in conjunction with NOTES:
1.)
the appropriate system operating transient definitions in Tabic 3; or they may use the proposed criteria contained in Tables 1-3.
See Table 3 for SOT definitions and other load abbreviations.
2.)
if setpoints are signifi-(and discharge sequence 3.)
The bounding number of valvesfor the applicable system operating transient. defined in Table l
cantly dif ferent)
Verification of functional capability is not required, but allowable loads 3 should be used.
l 4.)
and accelerations for the safety-relief valves must be met.
gr l
Use SRSS for combining dynamic load responses.
k 5.)
O a
6 t
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TABI.E 2A LOAD COMBINATIONS AND ACCEPTANCE CRITERIA FOR PRESSURIZER SAFETY AND RELIEF VALVE PIPING AND SUPPORTS - SEISMICAT.I.Y DESIGNED DOWNSTREAM PORTION Service Stress Plant / System Combination Operating Condition Load Combination 2 Limit 1
Normal N
A 7
Upset N + SOT B
g 3
Upset N + OBE + SOT C
g 4
Emergency N + SOT C
E 5
Faulted N + MS/FWPB or DBPB D
+ SSE + SOTp 6
Faulted N + LOCA + SGE + SOT D
p Plants without an FSAR may use the proposed criteria contained in Tables 1-3.
NOTES:
1.)
Plants with an FSAR may use their original design basis in conjunction with the appropriate system operating transient definitions in Table 3; or they may use the proposed criteria contained in Tables 1-3.
2.)
This table is applicable to the seismically designed portion of downstream non-Category I piping (and supports) necessary to isolate the Category I portion from the non-seismically designed piping response, and to assure acceptable valve loading on the discharge nozzle.
3.)
See Table 3 for SOT definitions and other load abbreviations.
4.)
The bounding number of valves (and discharge sequence if setpoints are significantly p
different) for the applicable system operating transient defined in Table 3 should r.
be used.
Verification of functional ca; - 'ility is not required, but allowable loads and 5.)
s accelerations for the safety // cilef valves must be met.
6.)
Use SRSS for combining dynamic load responses.
F TABLE 2B Revisien 1 LOAD COMBINATIONS AND ACCEPTANCE CRITERIA FOR PRESSURIIER SAFITY AND RELIEF VALVE PIPING AND SUPPORTS -
NON-SEISMICALLY DESIGNED DOWNSTREAM PORTION PIPING Service Plant / System Combination Operating Condition Lead Combination Limit 1
Normal N
A N + SOT B
2 Upset g
N + SOT C
3 Emergency g
4 Faulted N + SOT D
F SUPFORTS 1
Service Plant / System Combination Operating Condition Load Combination Limit A
1 Normal N
N + SOTg 2
Upset N + OBE + SOTg C
3 Upset C
N + SOTE
'4 Emergency 5
Faulted N + MS/FWPB or D
DBPB + SSE + SOTF
+ SOTF Plants without an FSAR may use the proposed criteria con-Plants with an FSAR may use their NOTES:
1.)
-tained in Tables 1-3.
original design basis in conjunction with the appropriate system operating transient definitions in Table 3; or they may use the proposed criteria contained in Tables 1-3.
l Pipe supports for the non-seismically designed down-stream piping should be designed for seismic lead combinations 2.)
to assure overall structural integrity of the system.
The bounding number of valves (and discharge sequence if 3.)
for the applicable setpoints are significantly different) system operating verification of functional capability is not required, but allowable loads and accelerations for the safety /
4.)
relief valves must be met.
Use SRSS for combining dynamic load responses.
5.)
Revision 1 TABLE 3 DEFINITIONS OF LOAD ABBREVIATIONS N
= Sustained Loads During Normal Plant Operation SOT
= System Operating Transient III SOT
= Re)4,ef Valve Discharge Transient g
= Safety Valve Discharge Transient (
SOTE SOT
= Max (SOTU; SOTg); or Transition Flow F
= Operating Basis Earthquako SSE
= Safe Shutdown Earthquake MS/FWpB = Main Steam or Feedwater Pipe Break DBPB
= Design Basis Pipe Break LOCA
= Loss of Coolant Accident (1)
May also include transition flow, if determined that required operating procedures could lead to this con-dition.
(2)
Although certain transients (for example loss of load) which are classified as a service level B conditions may actuate the safety valves, the extremely low probability of actual safety valve actu-ation may be used to justify this as a service level C condition with the limitation that the plant will be shut down for examination after an appropriate number of actuations (to be determined on a plant specific basis).
t NOTE:
Plants without an FSAR may use the proposed criteria contained in Tables 1-3.
Plants with an FSAR may use their original design basis in conju'nction with the appropriate system operating transient definitions in Table 3; or they may use the proposed criteria con-l tained in Tables 1-3.
I
~., - _, -. -.
-