ML20044D879
| ML20044D879 | |
| Person / Time | |
|---|---|
| Site: | 05200001 |
| Issue date: | 05/18/1993 |
| From: | Fox J GENERAL ELECTRIC CO. |
| To: | Poslusny C Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20044D880 | List: |
| References | |
| NUDOCS 9305210053 | |
| Download: ML20044D879 (6) | |
Text
g.
~
GE Nuclear Energy s e n k e.: c n n 173 Ct/?H Af%ot Sa'i
'!,c (A Ff 7.M May 18,1993 Docket No. STN 52-001
?
Chet Poslusny, Senior Project Manager Standardization Project Directorate Associate Directorate for Advanced Reactors and License Renewal Office of the Nuclear Reactor Regulation i
Subject:
Submittal Supporting Accelerated ABWR Review Schedule - Sample Pipe Break Analysis Report and Appendix 3L Modification
Dear Chet:
i Enclosed are SSAR markups of new Appendix 3L and the report GE-NE-123-E070-0493
" Sample Analysis for the Effect of Postulated Pipe Break ABWR Main Steam Piping". The Appendix 3L markups address NRC comments.
Please provide a copy of this transmittal to Shou Hou.
p Sincerely,
- /
Jack Fox Advanced Reactor Programs cc: Maryann Herzog (GE)
Norman Fletcher (DOE)
NDM 200012 9305210053 93053g.
[
.l
[DR.ADOCK 05200001
.gy}./
l PDR J
f.
./
/
'[
b E
3M4 PIPE RUPTTJRE EVALUATION b moment. angular deflection relationshipsl L-3I4.1 GENERAL APPROACH 4{:::
end DE) for any deflection for the case of a built in end. This equivalent force is -
j subtracted from the applied thrust force when There are several analytical approaches that U calculating the net energy.
may be used in analyzing the pipe / pipe whip restraint system for the effects of pipe rupture.
See Figures 5 2,5-3 and 5-4 for the models This procedure defines two acceptable approaches.
g described above.
I (1) Dynamle Time History Analysis With.E (2) Dynamic Time History Analysis with Simplified Model: A dynamic time history j Detailed Piping Model. In many cases it is f
i analysis of a portion of a piping system may 8 necessary to calculate stresses in the ruptured i
be performed in lieu of a complete system pipe at locations remote from the pipe whip analysis when it can be shown to be conservative by test data or by comparison jrestraint location. For example, the pipe in l
the containment penetration area must meet t-with a more complete system analysis. For.5 the limits of SRP 3.6.2. In these cases it is example, in those cases where pipe stressesf required the ruptured piping, the pipe need not be calculated, it is acceptable to supports, and the pipe whip restraints be model only a portion of the piping system as a modeled in sufficient detail to reflect its simple cantilever with fixed or pinned end or dynamic characteristics. A time history as a beam with fixed ends.
analysis using the fluid forcing functions at the point of rupture and the fluid forcing When a circumferential break is postulated, functions of each pipe segment is performed the pipe system is modeled as a simple to determine deflections, strains, loads to cantilever, the thrust load is applied structure and equipment and pipe stresses.
opposite the fixed (or pinned) end and the pipe whip restraint acts between the fixed end b
and thrust load. It is then assumed that all 3Y4.2 PROCEDURE FOR DYNAMIC deflection of the pipc is in one plane. As the TIME-HISTORY ANALYSIS WITH pipe moves a resisting bending momest in the SIMPLIFIED MODEL pipe is created and later a restraining force L,
at the pipe whip restraint. Pipe movement 3X'4.2.I Modeltag e(Piples SM-stops when the resisting moments about the
--W [/M5 EAT 3 L.de, E,1 A l
fixed (or pinned) cad exceed the applied r e n ;, p.p._ ;,, m m,-.;. ::r red thrust moment.
i-t ":: - '" resnam en = aaaa'"*d -
i-,m = S 2 ~- 8--d by = ~' " ; -
When a longitudinal break is postulated, the d S ;';' ; y
_.:~-3 = "A pipe system has both ends supported. To
. '--- ' x ;~ - M n ',
.L
.. 6. -
analyze this case, two simplifications are 5-2, 0 ",. '
- 0, M e > :_ de WWas made to allow the use of the cantilever model
- . C. ; f
- 27 The pipe whip restraint is described above. First, an equivalent point modeled as two components acting in series; the i
mass is assumed to exist at D (See Fig 5-4) restraint itself and the structure to which the instead of pipe length DE. The inertia restraint is attached. The restraint and piping characteristics of this mass. ss it rotates behave as determined by an experimentally or about point B, are calculated to be identical analytically determined force-deflection to those of pipe length DE, as it rotates r&
u. The structure deflect: as a simpic p
about point E. Second, an equivalent resisting linear spring of representative spring constant, force is calculated (from the bending i
rr.p u,, e 3X-3
l l
i INSERT 3L.4.2.1 a For many piping systems, all required informatien on their response to a postulated pipe rupture can be determined by modeling a portion of the piping system as a cantilever with either a fixed or pinned end. The fixed end model, as shown in i
Figure 5-2, is used for piping systems where the stiffness of the piping segment located between A and B is such that the slope of the pipe length, BD, at B, will be approximately zero. The pinned end model, as shown in Figure 5-3, is used for piping systems i
where the slope of the pipe length, BD, at B, is much greater than l
zero. The pinned end model is also used whenever it is not clear I
that the pipe end is fixed.
i A simplified cantilever model may also be used for a postulated E
longitudinal break in a pipe supported at both ends, as shown in Figure 5-4.
The pipe can have both ends fixed or have a pinned end at B and a fixed end at E, as shown in Figure 5-4. Section 3L. 4.l(l) discusses the simplification techniques used to allow the use of a cantilever model. A fixed end is used when the rotational stiffness of the piping at that location is such that the slope of the pipe at that end is approximately zero. A pinned end is
~
used when the pipe slope at that end is much greater than zero. If it is not clear whether an end is fixed or pinned, the end condition giving more conservative results should be assumed.
i 4
i f
i 4
F 6
i
d
)
t SIMPLIFIED PIPING M DELS W
M ("y jD
~/34
- ["["'
f
\\
y s
m
\\
ir
/
\\
}D
\\
- /*
i d
\\
64L* #NtitpN4 (
J gg mywe et a.m esus.n er suse aque
\\
fa
'g i
\\
l
\\
~
\\
d x
j.
e
/\\
e -g-l r
-\\
s:
~
N s
/
\\
t
(,
\\
c=-
I l
CVCu wha y
f g
e u. - a
~
b e
e
== e e
,e e
e s
1 E
i 1
~~-
\\ -
l7N/
g N ~[~~
j i
v_
x RR 35R I '
r U,
.dg l
m me e n
14 #,
l 4
~
- ~.
J.J v
/ w A,,
-6
[l i
r
5%Wtied Pipm3 Models j
Y/'
A I
/,
i 0
I B
s L
J f
Figure 51. Genent Representation of P:pe A
-l s
I i
. Fit!
II
'f B
C--
RESTRAINT 1
MODELED AS
[p i Flti v
V
}D B
C--
1 Figuro 5-2.
Representatron of BurII-In P:pe udk
'7S
/
a anuMt sent A
eit) v
/
D C==
RESTRAINT e
Ftti MODELED A$
((
[
v U
/'%
D i
j dB C--
~9A i
Figure 5 3.
Representation of Pinned-End Pope iskfh circunde<e.,tieI been k a
SIMPLIFIED PIPING MODELS A
g 8
C Fit)
D E
B C
D E'
lI RESTRAINT a
STRUCTURE N
s BEFORE THRUST DURING THRUST
- se ed et 8 ca be he) a f.~el.
B C
D B
C D
F(t) - FECUIV I
I F(t) - FEQUlv EQUlVALENT i
MASS
' j f EQUlVALENT i
MASS
\\
i BEFORE THRUST DURING THRUST f
l 8
c D
6 c
D
[F00- FreuW FO)-Feocio j
g T
A 1
P gooioALWT
/,
r MASS i
1 i
EQ984RLGAT m,,,
BEFoRE THRoST D#dN6 THMST l
Figa Ei-4 Rgrese4tix & Vye adk wk was sugated win 4 fonyhdWI bred l