ML13317A526
| ML13317A526 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 02/28/1983 |
| From: | Baskin K Southern California Edison Co |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| TASK-03-06, TASK-3-6, TASK-RR NUDOCS 8303070079 | |
| Download: ML13317A526 (11) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 K. P. BASKIN TELEPHONE MANAGER OF NUCLEAR ENGINEERING.
February 28, 1983 (213) 572-1401 SAFETY, AND LICENSING Director, Office of Nuclear Reactor Regulation Attention:
Mr. D. M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Gentlemen:
Subject:
Docket No. 50-206 SEP Topic 111-6 Seismic Design Considerations San Onofre Nuclear Generating Station Unit 1 On February 17, 1983 we met with the NRC Staff to discuss issues related to the seismic reevaluation of piping at San Onofre Unit 1. The purpose of this letter is to document that our approach on these issues is as described in the enclosed pages which were provided at the February 17 meeting. With the exception of the method for evaluating seismic anchor movement stresses on piping as discussed in the enclosed pages, the criteria and methodology for the evaluation of piping and equipment at San Onofre Unit 1 are in accordance with the NRC Guidelines which were provided by letter dated September 20, 1982.
If you have any questions on this matter, please let us know.
Very truly yours, PD AOCX9 8322 PDR
.2
METHODS FOR COMBINATION OF SEISMIC ANCHOR MOVEMENT AND SEISMIC INERTIA RESPONSES OF PIPING o
DISPLACEMENT OF ADJACENT INDEPENDANT STRUCTURES USED FOR DEVELOPING SEISMIC ANCHOR MOVEMENT LOADS AND STRESSES o
LOADS DUE TO INDEPENDANT SEISMIC RESPONSES OF ADJACENT PIPES ON COMMON SUPPORTS o
LOADS DUE TO INDEPENDANT SEISMIC RESPONSES ON EACH SIDE OF AN ANCHOR, ABSOLUTE SUMMATION:
o SEISMIC ANCHOR MOVEMENT AND SEISMIC INERTIA LOADS o
SEISMIC ANCHOR MOVEMENT AND SEISMIC INERTIA STRESSES
ACCEPTANCE CRITERIA FOR SSE SEISMIC ANCHOR MOVEMENT STRESSES o
INCLUDED IN EQUATION 9 IF OMITTED FROM EQUATION 10 OR 11 o
EQUATION 9 ALLOWABLE LIMITED TO:
1,8SH FOR CLASS 1 2,4SH FOR CLASS 2/3 o
IF LIMITS OF EQUATION 9 ARE EXCEEDED DUE TO THE INCLUSION OF SSE SEISMIC ANCHOR MOVEMENT (SAM)
STRESSES AN AUGMENTED CLASS 2/3 EVALAUTION WILL BE PERFORMED.
EQUATION 9 FROM NC-3652 P90 + 75 MA + M-
- KSH, EQ. 9 4TN Z
MA = RESULTANT MOMENT LOADING ON CROSS SECTION DUE TO SUSTAINED LOADS MB = RESULTANT MOMENT LOADING ON CROSS SECTION DUE TO OCCASIONAL LOADS. FOR EARTHQUAKE, USE ONLY ONE HALF THE RANGE.
K =
1.8 FOR CLASS 1 EVALUATED USING CLASS 2 RULES 2.4 FOR CLASS 2/3 NOTE:
MB = MB (SSE SI)I + 1MB (SSE SAM)!
WHERE SSE SI = SSE SEISMIC INERTIA SSE SAM = SSE SEISMIC ANCHOR MOMEMENT
AUGMENTED CLASS 2/3 METHOD o
MAXIMUM INTENSIFIED STRESS RANGE WILL BE CONSERVATIVELY LIMITED TO 100 KSI o
THERMAL STRESSES WILL MEET THE REQUIREMENTS OF EQUATION 10 OR 11 o
SEISMIC INERTIA STRESSES WILL MEET THE REQUIREMENTS OF EQUATION 9
AUGMENTED CLASS 2/3 METHOD o
CALCULATION OF INTENSIFIED STRESS RANGE
~iS LIMIT SWT + SLP + STH + SSSE + SSSE 100 KSI SI SAM SWT + SLP + 2 SSSE + SSSE 100 KSI SI SAM WHERE:
SWT = WEIGHT STRESS SLP = LONGITUDINAL PRESSURE STRESS STH = THERMAL STRESS RANGE SSSE = SSE SEISMIC INERTIA STRESS, 1/2 STRESS RANGE st (MODIFIED TO INCLUDE FULL l )
SSSE = SSE SEISMIC ANCHOR MOVEMENT STRESS, SAM 1/2 STRESS RANGE (USING FULL.L )
EXPLANATION OF SEISMIC ANCHOR MOVEMENT CRITERIA
AUGMENTED CLASS 2/3 METHOD o
USING THE MARKL S-N CURVE, APPROXIMATELY 100 MAXIMUM STRESS CYCLES ARE AVAILABLE AT THE 100 KSI STRESS LEVEL o
LIMITING THE INTENSIFIED STRESS RANGE TO 100 KSI ASSURES THAT THE CUMULATIVE USAGE FACTOR WILL BE LESS THAN 1.0 BECAUSE THERE ARE LESS THAN 100 MAXIMUM STRESS CYCLES DUE TO THE EARTHQUAKE o
EQUATION 9 WITH INCLUSION OF SSE SAM HAS BEEN SHOWN TO AUTOMATICALLY SATISFY THE REQUIREMENTS OF THE AUGMENTED CLASS 2/3 METHOD (EVEN WITH THE 100 KSI INTENSIFIED STRESS RANGE LIMIT)
NUMBER OF CYCLES 10 102 103 115 106 10 3.
IICLA SS 1D ESIPG3N PATIGJE 'CURVE, IRDUCED II BY K FOR A106 GrB MATERIAL.-I......
/ALUES CLASS 1 DESIGN FATIGUE CURVE OF s
(KSI)I a
iIII..IiI~I'
-1 ACLASS 2/3 QUATIN (11) IMIs 1Y FORA10 II 100 ATarkl FATIGUE CURVE rE COMPARISON OF AUGMENTED CLASS 2/3 FATIGUE LIMITS ITII CLASS DESIGN FATIGUE CURVE
AUGMENTED CLASS 2/3 METHOD o
VERIFICATION THAT LIMITING THE INTENSIFIED STRESS RANGE TO 100 KSI ASSURES A CUMULATIVE USAGE FACTOR OF 1.0 OR LESS o
PER SRP 3.7-3 NUMBER OF MAXIMUM STRESS CYCLES DUE TO EACH EARTHQUAKE IS 10 EVENT S
N N
D= N NORMAL OPERATING 30,000 36,327 7,000.
.19 SSE EARTHQUAKE 100,000 100 10
.10 CUMULATIVE USAGE FACTOR =
.29 EVENT S
N N
D= N NORMAL OPERATING 30,000 36,327 7,000
.19 SSE EARTHQUAKE 100,000 100 60
,60 CUMULATIVE USAGE FACTOR
=
.79
ACCEPTANCE CRITERIA FOR SSE SEISMIC ANCHOR MOVEMENT STRESSES o
USE OF AUGMENTED CLASS 2/3 METHOD BUT CONSERVATIVELY LIMITING THE MAXIMUM INTENSIFIED STRESS RANGE TO 100 KSI o
IF SSE SAM STRESS IS INCLUDED IN EQUATION 9 THE REQUIREMENTS OF THE AUGMENTED CLASS 2/3 METHOD ARE AUTOMATICALLY SATISFIED o
USAGE FACTORS NEED NOT BE CALCULATED SINCE LIMITING THE MAXIMUM INTENSIFIED STRESS RANGE TO 100 KSI PROVIDES FOR APPROXIMATELY 100 MAXIMUM STRESS CYCLES