ML15236A314
| ML15236A314 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 08/23/2015 |
| From: | Beltz T Plant Licensing Branch III |
| To: | Kish H, Scarpello M American Electric Power, Indiana Michigan Power Co, (Formerly Indiana & Michigan Power Co) |
| References | |
| TAC MF6639 | |
| Download: ML15236A314 (4) | |
Text
1 NRR-PMDAPEm Resource From:
Beltz, Terry Sent:
Sunday, August 23, 2015 7:41 PM To:
'Michael K Scarpello'; hlkish@aep.com Cc:
Alley, David; Tsao, John; Pelton, David
Subject:
Donald C. Cook Nuclear Plant, Unit 2 - Proposed Alternative to the ASME Code,Section XI, Repair Requirements Attachments:
Socket weld.docx Michael and Helen, The NRC staff has requires additional clarification related to your August 23, 2015, request associated with the Indiana Michigan Power Company (I&M) proposed alternative to the American Society of Mechanical Engineers (ASME) Code,Section XI, repair requirements to apply a weld overlay, with a deviation from ASME Code Case N-666, to a defect in the boric acid makeup system piping. Please refer to the attached document regarding socket welds.
Item C-1 (two drawings on left) are slip-on flanges. Item C-2 (single drawing on right) is flange socket weld.
Item C-3 is another socket weld. The August 23, 2015, application indicates the affected component is socket weld FW-17. However, based on the attached drawings, the drawing supplied in Section 7 of your application does not clearly represent a socket weld. This, at the very least, indicates that the I&M may require two alternatives from the code case: 1) a mechanism other than fatigue, and 2) apply socket weld code case to a weld that is not a socket weld.
Therefore, the NRC staff requires a better drawing of the subject component to clearly indicate if it is a slip-on flange or a socket weld flange. In other words, if this is a socket weld then a better drawing is requested. If it is not a socket weld, then you need to revise your request to reflect that the weld in question is not a socket weld and provide further discussion regarding that alternative to the code case.
Please let me know if you have any additional questions.
Sincerely, TERRY A. BELTZ, SENIOR PROJECT MANAGER U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Mail Stop: O-8D15 Phone: (301) 415-3049 Terry.Beltz@nrc.gov Confidentiality Notice: This email message, including any attachments, contains or may contain confidential information intended only for the addressee. If you are not an intended recipient of this message, be advised that any reading, dissemination, forwarding, printing, copying or other use of this message or its attachments is strictly prohibited. If you have received this message in error, please notify the sender immediately by reply message and delete this email message and any attachments from your system.
Hearing Identifier:
NRR_PMDA Email Number:
2330 Mail Envelope Properties (5114639e6b7b472290b79cf680bf418b)
Subject:
Donald C. Cook Nuclear Plant, Unit 2 - Proposed Alternative to the ASME Code,Section XI, Repair Requirements Sent Date:
8/23/2015 7:40:44 PM Received Date:
8/23/2015 7:40:45 PM From:
Beltz, Terry Created By:
Terry.Beltz@nrc.gov Recipients:
"Alley, David" <David.Alley@nrc.gov>
Tracking Status: None "Tsao, John" <John.Tsao@nrc.gov>
Tracking Status: None "Pelton, David" <David.Pelton@nrc.gov>
Tracking Status: None
"'Michael K Scarpello'" <mkscarpello@aep.com>
Tracking Status: None "hlkish@aep.com" <hlkish@aep.com>
Tracking Status: None Post Office:
HQPWMSMRS05.nrc.gov Files Size Date & Time MESSAGE 2345 8/23/2015 7:40:45 PM Socket weld.docx 129200 Options Priority:
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Recipients Received:
NC-3660 DESIGN OF WELDS NC-3661 Welded Joints NC-3661.1 General Requirements. Welded joints shall be made in accordance with NC-4200.
NC-3661.2 Socket Welds28 (a) Socket welded piping joints shall be limited to pipe sizes of NPS 2 (DN 50) and less.
(b) Socket welds shall comply with the requirements of NC-4427.
(c) Drains and bypasses may be attached to a valve or a fitting using socket welded joints up to a maximum of NPS 4 (DN 100).
NC-3661.3FilletWeldsandPartialPenetrationWeldsforBranchConnections29 (a) Filletweldsandpartialpenetrationwelds maybeusedwithinthelimitationsofNC-3643.1(c).
(b) Forfilletwelds,thesizeoftheweldshallbe specifiedonthedesigndrawings.
(c) Forpartialpenetrationwelds,thesizeofth eweld,thedepthoftheweldgroove,andthegroov eangleshall be specifiedonthedesigndrawings.
28 Socket welds should not be used where the existence of crevices could accelerate corrosion.
29 Fillet and partial penetration welds should not be used where severe vibration is expected.
FIG.NC-4427-1 FILLETANDSOCKETWELDDETAILSANDDIMENSIONS Sizeofweld Theoreticalthroat SurfaceofverticalmemberC onvexfilletweld Surfaceof horizontalmember Theoreticalthroat SurfaceofverticalmemberC oncave filletweld Sizeofweld (a) EqualLegFilletWeld[Note(1)]
Theoreticalthroat SurfaceofverticalmemberC onvexfilletweld Theoreticalthroat SurfaceofverticalmemberC oncave filletweld Surfaceof horizontalmember (b) UnequalLegFilletWeld[Note(2)]
x,min.
x,min.
tn x,min.
x,min.
tn whicheverissmaller 1/16in.(1.5mm)approxb eforewelding Frontandbackweld Faceandbackweld (c-1)Slip-OnFlange[Note(3)]
(c-2)SocketWeldingFlange[Note(3)]
Cx tnnominalpipe wallthickness 1/16in.(1.5mm)approx.
beforewelding NOTES:
(1) Thesizeofanequallegfilletweldistheleglengthofthelargest inscribedrightisoscelestriangle.Theoreticalthroat= 0.7x sizeofw (2) Thesizeofanunequallegfilletweldistheshorterleglengthofthelargestri ghttrianglethatcanbeinscribedwithinthefilletweldcross-section.
(3) x,min.=1.4tnorthethicknessofthehub,whicheverissm aller,butnotlessthan1/8in.(3mm),wheretn= n ominalpipewallthickness (4) Cx,min.=1.09tnwheretn= nominalpipewallthickness (c-3)SocketWeldingFittings[Note(4)]
x,min.
x,min.
t tnor1/4in.(6mm),which everissmaller tnor1/4in.(6mm),