ML19211C493
| ML19211C493 | |
| Person / Time | |
|---|---|
| Issue date: | 12/07/1979 |
| From: | Bennett G NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | Tiller R ENERGY, DEPT. OF |
| References | |
| REF-GTECI-A-09, REF-GTECI-SY, TASK-A-09, TASK-A-9, TASK-OR NUDOCS 8001110504 | |
| Download: ML19211C493 (5) | |
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DEC 7 1979 Mr. Robert E. Tiller, Director Reactor Operations and Frograms Division U.S. Department of Energy 550 Second Street Idaho Falls, Idaho 83401 h
Dear Mr.
The Nuclear Regulatory Comission is developing a program to obtain additional infomation on the behavior of pressurizer safety and relief valves under transient and accident conditions.
I am writing this letter to call your attention to this program and to determine if INEL is interested in being the systems integrator for the program.
Enclosed is a draft workscope which describes in general tems what NRC is interested in.
Basically, we see the need to:
1.
technically monitor and analyze the planned EPRI/ industry valve testing program, and collect and evaluate foreign information; 2.
develop or improve available flow discharge model(s), using the above information; and 3.
detemine the need for a valve testir.g program for NRC with the main focus to be on subcooled and two-phase discharge and on determining operability.
Included in this effort will be an assessment of the fluid / structural interactions with the valve and piping.
The systems integrator for this effort should have demonstrated capabilities to:
1.
operate system codes (e.g., RELAP, TRAC) and structural codes;
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2.
develop models for flow through valves; 3.
technically monitor and evaluate valve research; and 4.
manage a reasonably extensive testing program on full-scale valves, if this should prove to be needed.
1736 079 800111o s g
. DEC 71979 26bett E. Tiller If INEL is interested in this program we would appreciate receiving a draft program and budget proposal along with a discussion of the interest e d resources available at INEL to assist istC in this activity. A writte., response by Jesutry 1. 1980 would be appreciated.
y please feel free to call Milt Stolzenberg or me (both on FTS 427-4272; commercial (301/427-4272) if you require additional infoma_ tion.
sincereiy, Original Signed by Gary L Bennett Gary L. Bennett, Chief Research Support Branch Division of Reactor Safety Research
Enclosure:
Draft Workscope cc w/ enc 1:
W. Loewenstein. EPRI W. Layman, NSAC kmu hg) Jgj,,,,),! W,,,Oj',
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IfD C. Sullivan EPRI j\\ lr"d a L. J. Tharrondo, EG&G bec:
A. Thadani S. Hanauer J. 01shinski R. Mattson E. Brown W. Anderson C. Graves W, Vesely J. E. Richardson DISTRIBUTION SUBJ CIRC CHRON BRANCH RF GLB RF GLB CY MS CY HS CY 1736 080 J Y LST CY TEM CY The proposed workscope has been reviewed with NRR and will be RECORD NOTE:
Similiar letters to fonnally documented in a Research Request from NRR. DOE; F. R. My R. E. Tiller.
Engineering Center; G. C. werth, LLL; G. R. Otey, Sandia; N. E. Carter, PNL; and J.,A._ Kyger, ANL.
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NRC Form 3188 (4-79) NRCM 0240
ENCLCSURE DRAFT WORKSCOPE ON CONFIRMATORY RESEARCH i
RELATED TO THE BEHAVIOR OF SAFETY AND, RELIEF VALVES Information Needs 1.
Data are still needed to confirm the current procedure for estimating valve flow characteristics under subcooled or two-phase flow conditions.
(0.9 x Homogeneous Equilibrium Model).
2.
In addition, data are required to permit confirmation of the following:
a.
The valve operating characteristics for full opening, chatter, closing pressure.
b.
The effects of back pressure on valve capacity.
c.
Procedures for calculating valve reaction forces.
3.
It will be necessary to review and monitor the industry tests of functionability of safety and relief valves and associated piping systems. This is necessary to ensure that:
a.
Testing perfonned is adequate to qualify systems and valves, b.
Data obtained can contribute to information needs of Item 1 and 2 above.
c.
Extrapolation of representative tests are adequate to qualify systems and valves not tested.
Foreign research information on valves should be obtained and evaluated.
4.
The following phenomena and parameters should be evaluated based on test results, extrapolation of test results and on appropriate models:
a.
Flow Rate - cover full range of anticipated flow rates 1.
Fluid saturated steam two-phase saturated water subcooled water 2.
Conditions Pressure (psi)
Temperature 'F 500-600 100 (PORV only) 2300-2800 s 400-600 2800-3800 600-700 1736 081 3.
Ef'ect of Piping Configuration on Flow b.
Failure Mechanism 1.
Effects of Intermittent Water on Two-Phase Slugs; Efft.ct of Sudden Change in Density of the Fluid Reaching the Valve 2.
Effect of Upstream and Downstream Piping Configuration and Supports (Constraints) t
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Schedule NRC/NRR intends to proceed with ATWS rulemaking in early 1980.
A description of the industry test program and schedule of testing will be submitted by January 1,1980.
Sufficient data must be available by December 1981 to allow NRC to assess with reasonable confidence the adequacy of the proposed ATWS fixes.
We believe that by March 1980 there should be sufficient information from the industry test program as to what can be expected from this program.
At that time, planning for NRC-sponsored testing should begin if necessary.
Monitoring of industry programs plus evaluation of data will continue until the testing is complete, data has been evaluated, other plant configurations have been evaluated relative to the test data and models developed are confirmed.
This could be 6 months after the completion of testing.
program Requirements The research program should fulfill the above information needs. This program shculd include the following:
1.
Identify the model(s) that could be used to describe the flow through safety and relief valves as affected by the dynamics of valve disc motion. This should include steam, two-phase, and subcooled water discharge conditions.
2.
Compare calculations with experimental data from the tests in U.S. and abroad.
3.
Identify the error band of the present models, through comparison with test data, and improve the selected model if error band found to be too large.
4.
Verify the hydraulic load calculations in the valve associated piping and supports for both steady-state and transient tests.
5.
Classify potential valve failure modes associated with valve operation.
6.
Monitor industry test programs to comply with TMI Lessons Learned Short-Term Recomendations. This should include the following:
Review proposed test programs to ensure testing will provide informa-a.
tion to qualify safety and relief valves and associated piping systems.
b.
Determine whether additional test data could be obtained from industry tests to pennit verification of calculations of (2) and (3) above.
c.
Monitor and evaluate testing and collection of data.
d.
Monitor and evaluate application of test data to existing valves and systems other than specific application tested.
7.
Monitor and evaluate test data from foreign facilities for application to information needs.
8.
Determine need for additional testing depending upon projected results of U.S. and foreign tests.
9.
Identify corrective measures if failure modes associated with valve operatior are discovered.
Use of Results Models developed and confirmed by test data generated by the industry (and supplemented by additional testing if necessary) are required by the NRC to judge the adequacy and behavior of pressure relief valves and associated piping systems on PWR and perhaps BWR nuclear power plants.
1736 083