ML19330B454
| ML19330B454 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 07/30/1980 |
| From: | Sylvia B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | Harold Denton, Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| 672A, NUDOCS 8008040042 | |
| Download: ML19330B454 (3) | |
Text
_
< 4 VIMOINIA EI sCTRIC AND Pownw CoxrAny Racunown VamorazA 20261 July 30, 1980 Mr. Harold R. Denton, Director Serial No. 672A Office of Huclear Reactor Regulation N0/RMB:smv Attention:
Mr. B. Joe Youngblood, Chief Docket No. 50-339 Licensing Branch No. 3 License No. NPF-7 Division of Licensing U. S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Denton:
CONTAINMENT PRESSURE BOUNDARY FRACTURE TOUGHNESS REQUIREMENTS NORTH ANNA UNIT NO. 2 The following additional information is provided in response to NRC questions concerning the material properties and operating conditions of the forged steel attachment plates used in the fabrication of the hot piping penetrations on North Anna Unit No. 2:
1.
The attachment plate material is a carbon steel forging ASTM No. A350-LFI-20.
2.
The largest forging is used on the piping penetration for the main steam lines and is approximately 6" x 9".
3.
The forgings were acceptably drop weight tested at -20*F in accor-dance with ASTM-E208.
The nil ductility transition temperature would, therefore, be below the test temperature of -20*F.
A copy of a detailed analysis report is attached showing the test results for a typical 6" forging.
4.
The minimum temperature of the forged attachment plate for the main steam and feedwater penetrations (largest forgings) during normal plant operations would be approximately 350*F and 230*F, respectively.
The forgings could reach a much lower temperature when the plant is at cold shutdown, however; the forging would be at a lower stress level under this condition.
If the penetration attachment plate were assumed to reach the minimum service water (cooling medium) design temperature of 30*F, a margin of 50*F would still exist above the tested NDT temperature. This exceeds the 30*F margin recommended in paragraph NE-2300 of ASME III.
It should be noted that it is highly unlikely that the service water temperature at the penetration coolers could ever reach 30*F and, in any event, the forged attach-ment plate would not reach this temperature since it is separated from the cooling water and heated by the containment ambient temper-ature.
8008040 0 8
visoix A Etscruic ano Powra COMPANY To Mr. Harold R. Denten, Dircctor ' Since the minimum possible temperature of the piping penetration materials is well above the nil ductility transition temperature, we feel that the supplied penetration materials are suitable for all anticipated plant conditions.
Please contact us if you require any additional information.
4 Very truly yours, s
B. R.
Ivia Manager - Nuclear Operations and Maintenance RMB/sav:SR2 cc:
Mr. James P. O'Reilly, Director Office of Inspection and Enforcement Region II Atlanta, Georgia 30303 i
h
L j
j
[
t 1
i i
i 1
>E t
c ZO
> rr (W
d Eg M,
3 wg Ig 3
f>E m
ct 6
w a
4 t
I i
C e
H
,lb I
I
]
.a.
_64>
?
?
I5 E
G Id c
o l
o o
(
4 w
N I
?
t I
'5
~
l 4
5 "a
{ be o
{
g y
Ek s
g r4 til.
l $m g
5 f hh
)
5 t 1 R
83 Z
p N
m 3
l m
3 k
4 m)
F y
y p
9 10 De
.4 O
E-e l
0 u
2 4 i,. *
\\
1 m
a 5
=
D 5
t* W 2
c' i
e a
o o
o e
o g u0
-I N
o p
g U
e
.O r.4 t+
8 5
E-e k
lZ!
g o
m I
a 93
- I m
z 4
i E @
M t 8
i a
g a
e
[
u o
- m. c.
o Ie o
s
==
8-O' N
O 5.
v-l (d
"O 4
I Qc
( 4 l
4}.
_C1 (f1 J
- 4. 4 1
e 5t3 u
cr x
a US "ii!I g
6 4
-1 m
a 3
O,.
1 gj g
5 C
i W
.si,~
"f
_a a
p g
,lf r.
o
.a J a' 9
r o
3 3ljijI R
5
". d 6 d
..r.
is 8
t M
l m
r e.
e s
a o
q o
n
.5 E
z.
IlI 4
4
- e. E g
W.
l1 r
3
,1 o
1 15$,
=R 8.nz 3 e
.syr n'S l
x a-E E
o I
$s c
E*
t O
i i
i m
g 5
b Q
Q Q
lL I
3 e
5 x
x x
a O
l 4..C
-O A
K at
=
...J.H -
A L
=
i o
o o
m o
e n
=
5 c.
e r
e e
n a
' ;9
,< M..
j 1:
a
~
n a
m Y
(, h.
gi
',)
'...T, a,P g,
g u
o s
- k r
CL u. ' ' t'.
./* _
9 l
l l
I I
3.
1
. - _ _ - - _..