ML20024G319
| ML20024G319 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point, Monticello  |
| Issue date: | 12/10/1971 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Wachter L NORTHERN STATES POWER CO. |
| Shared Package | |
| ML20024G313 | List: |
| References | |
| NUDOCS 9102110292 | |
| Download: ML20024G319 (2) | |
Text
-_
a s.
i December 10, 1971-l1r uY;
.1 Northern States Power Company
~ Docket No. 50-263
't ATIK Leo Vachter, Vice President 4
Pou r Producties 419 Nicollet Annue Minneapolis, Minneesta 53401 -
Centleman:
The following was ser.t to you by telegram on December 9,1971.
We recently received information from the Florida Power and-Light Conpany of an occurrence during preoperational testing of the Turkey Point 3 Westinghouse. pressurized water reactor that may relate to performance of the stesa supply system at your facility.
The information is as follows:
During hot functional testinp, of the unfueled reactor, three of four reifef valves wore catastrophically ajected from two main steam line headers, to which they vero counted. The failed headers vera 12-inch dinnetor, spool pieces fabricated-by the Dravo Corporation, Marietta, Ohio, from Schedule 60
-(.562-inch vall thickness) A106, Grade B carbon steel pipe p
nanufactured by U, S. Stoel, Lorain Works, forain, Ohio, s:ounted i
horizontally,1800 from each other, on the two sides of the
~
g main steam ifne. The headers were hydrostntically tested at 1356 psin under cold conditionn prior to hot functional testing.
On one side of the main steen line, the failure occurred in i'
the vicinity of the heat affected -sono of the weld which joins i
the riser to the header and appears to be largely_ confined to the 12-inch header. On the other side of the main steam line, the failure apparently originated in a sinflar manner and propagated through the pipe header causing catastrophic damage I
to the header assembly. The secondary system was at 990 psig and 545cF and the primary system at 2231 psig and 546.6 F st is
+
. n,-
f I
g
- \\
9102110292 720117 PDR ADOCK 05000263 p
,A f
^ '
- ,u,,,,
2-December 10, 1971 Northern States Power company the time of the' header failure. These systems had been at their respective pressures and temperatures for nine days. No
' 5,,,
transient conditions were reported to have existed in these systems at the time of failure.
The failed header assemblies each consist of two valves mounted vertically in a dead-end,12-inch diameter pipe projecting at a 90*
horizontal angle from the main steam line. The two headers are mounted at 1800 to each other on the opposite sides of the main steam line. The head 6rs were designed to meet Section 1 of the ASME Code by the Bechtel Corporation.
For your reactors which are licensed to operate, it is requested that you provide this office within ten days, in writing, as to whether headers as described above are installed in the steam lines of your facility.
a Should you have any questions eencerning this matter, we will discuss them with you.
Sincerely yours, 1
Boyce H. Criar Regional Director bec w/1tr dtd 12-17-71:
3 J. G. Keppler, CO e
L. Kornblith, CO R. H. Engelken, CO P. A. Morris, DRL CO Files DR Central Files PDR
/
Local PDR NSIC R. L. Shannon, DTIE
. 1
.I I
k O
p 9
)
e-4
-, - - -.,