ML18031A162

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Forwards Final Rept of Undersized Welds on safety-related Pipe Hangers
ML18031A162
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 04/06/1979
From: Curtis N
PENNSYLVANIA POWER & LIGHT CO.
To: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML17138A569 List:
References
NUDOCS 7904120263
Download: ML18031A162 (5)


Text

.0 REGULA TORY liVFORMATION D I STHIOUTION SYSTEM (R IPS)

ACCESSION IVBRo 7904120263 DOC ~ DA I'E o 79/04/06 NOTARIZED < NO DOCKET FAG IL:50 387 SUSQUEHANNA STEAM ELECTRIC S TATION UiVIT 1 PEtVNSYLVA 050003 50-388 SUSQUE<AiutuA STEAM ELECTRIC STATION UNIT 2 PENNSYLVA 0500 8 AUTH ~ NAtlF AUTHOR AFF IL I A SION C UR T IS F N ~

'TBT' PFNiNS YL V AN IA POWER tt L IGH T CO ~

HECIP,iVAME HECIP IENT AFFILIATION GRIEH FB ~ H ~ REGION 1 PHILADELPHIA OFFICE OF THE DIRECTOR

SUBJECT:

FORWARDS FlNAL HEPT Uf: UNDERSIZED 'r'ELDS ON SAFETY RELATED PIPE HANGFHS~

g 0-s8'7 8, DISTRIBUTION COOK: BDINS COPIES RE E IVES:L f ENCL J SIZE: 5+~~

TITLE: CONSTRUCTION DEFICIENCY REPORT (IOCFN50 ~ 555) ~

NOTES: +~D 5 +~ >~Cg F5' Rlt '&TOTS ~

RECIPIENT COPIES REC IP IENr COPIES IO CODE/NAME LTTH ENCL ID CODE/NAME LTTR ENCL AC T ION: 14 Ptl H<p46fZ. 1 1 15 BC tF @le g 1 1 20 LA C EE)g AD <MMc.c O INTERNAL: 0 1 02 NHC PDR 1 1 05 IHE 2 2 07 EOO 8 STAFF 1 1 08 tlP A 1 1 09 OEPY OIR DPM 1 1 10 QAB 1 1 11 STANORDS OFV 1 1 12 JDROANt E/IE 1 1 13F IELD COOR/ IE 1 1 16 AO FOR ENGR 1 1 17 AO PLANT SYS 1 1 17 AO REAC SFTY 1 1 19 AD SYS/PROJ 1 22 DIR DPM 1 23 OELD 1 1 EXTERNAL: 03 LPOR 1 1 04 NSIC 24 ACRS 16 lb

<PR 18 1ggg TOTAL IVUMt3ER OF COP IES REQUIRED: LTTR 39 ENCL 39

TWO NORTH NINTH STREET, ALLENTOWN, PA. 18101 PHONE: (215) 821 5151 NORMAN W. CURTIS Vice President Engineerin8 IL Ccnstrtrcticn 821-5381 April 6, 1979 RECULATQi<'( Dxitg FiLE gopy.

Mr. Boyce H. Grier Director, Region I U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 17406 SUSQUEiQuQlA STEAM ELECTRIC STATION FINAL REPORT OF UNDERSIZED WELDS ON SAFETY RELATED PIPE HANGERS DOCKET NOS: 50-387/50>>388 LICENSE NOS: CPPR-101/CPPR-102 ERs 100450/100508 FILE 840-4 PLA-343

Dear Mr. Grier:

This supplements our letters PLA-202 dated December 1, 1977, PLA-239 dated April 6, 1978, and PLA-316 dated February 2, 1979 and represents the final report relative to the subject deficiency which was reported under the provisions of 10CFR50.55(e).

The deficiency involved dimensionally undersized welds on safety related pipe hangers fabricated for the Susquehanna Steam Electric Station by ITT Grinnell, Warren, Ohio undex'echtel Purchase Order 8856-P-3. The nonconforming conditions represented a deviation from hanger detailed design drawings and required an extensive evaluation of the "as-fabricated" undersized welds.

Investigation of the problem revealed that the problem resulted, in part, from the fact that the specification for shop fabrication of hangers (8856-M-209) lacked specific criteria for the acceptance/refection of welds. This situation was corrected when, on October 18, 1977, Revision 11 of P.O. 8856-P-3 was transmitted to the supplier and pxovided a revised Specification 8856-M-.209 which included appropx'iate inspection acceptance criteria.

Having established the necessary inspection criteria for future production of pipe hangers, an extensive reinspection program for all hangers produced by ITT Grinnell prior to October 18, 1977 was instituted by Bechtel OC at the SSES construction site on December 1, 1977 and was devised to prevent the

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Mr. Boyce H. Grier April 6, 1979 installation of nonconforming hangers; to verify the supplier's compliance to the new fabrication and inspection requirements; and to provide orderly controls for continuing construction installation activities. Visual inspections by Bechtel QC confirmed the acceptability of all Q-listed hangers shipped by ITT Grinnell after 10/18/77.

On December 12, 1977, the Bechtel inspection effort was directed towards all hangers at SSES which had been fabricated prior to the October 18, 1977 date.

All welds on pipe supports and hanger components were examined by Bechtel in accordance with Article 9 of ASME B&PV Code Section V-1971 and the following ANSI Standard B31.1 visual acceptance criteria:

~ Unacceptable indications (1) Cracks - external surface.

(2) Undercut on surface which is greater than 1/32 inch deep.

(3) Weld reinforcement greater than that specified in a table in Para. 127.4.2 of the ANSI B31.1 Standard.

(4) Lack of fusion on surface.

(5) Incomplete penetration (applies only when inside surface is readily accessible).

~ Fillet weld minimum dimensions as specified in ANSI B31.1-1973.

As necessary, during the Bechtel inspection effort, which was undertaken on 12/12/77 and concluded on 3/15/78, welds which did not meet specification requirements were reworked.

On March 15, 1978 Bechtel QC concluded the primary inspection function and ITT-Grinnell quality'ontrol personnel assumed the inspection function on-site employing the same (Bechtel) visual inspection acceptance criteria. Prior to initiating the inspections, Grinnell's QC Program was submitted to and approved by Bechtel Engineering.

At the outset of ITT-Grinnell's inspection effort, Bechtel QC held a preparatory meeting with ITT-Grinnell and established Bechtel QC surveillances, reviews and witness and hold points. (Bechtel QC documents its activities on Field Inspection Reports which are prepared weekly.)

There is a computer listing of pipe hangers which has been modified to provide a record of all the safety-related pipe hangers affected. The listing provides columns designating the hangers which, as determined by the Bechtel survey, have been judged acceptable or have been designated as requiring rework. These records have been updated to reflect where rework'as accomplished and the status of the acceptability of the welds affected. These records reflect the interim (12/1/77 to 3/15/78) Bechtel inspection and rework effort.

Mr. Boyce H. Grier April 6, 1979 Records of ITT-Grinnell's activities are maintained in accordance with its QC Program. The records of Bechtel and ITT-Grinnell inspections are being kept as separate documents. Both sets of records contain similar pertinent information.

In conjunction with its inspection effort, ITT-Grinnell prepared the attached report of the results. and an analysis to verify the adequacy of the Susquehanna Project's hangers which were fabricated by ITT Grinnell in the fulfillment of Bechtel Purchase Order i/8856-P-3-AC Rev. 12. This report has been reviewed and accepted by Bechtel Engineering who have stated:

"In summary the conclusions of the report substantiate the adequacy of the Q-Listed hangers in question because:

(a) All Q-Listed hangers shipped prior to 10/18/77 were inspected for undersized welds as well as for compliance with the revised specification requirements for visual weld acceptance criteria.

(b) All Q-Listed hangers with undersized welds were analyzed in the "as-fabricated" condition to determine stress levels of the undersized welds.

(c) None of the Q-Listed hangers with undersized welds were found to have weld stresses that exceeded the agreed upon allowables.

(d) The ITTWrinnell analysis of the undersized welds in the Q-Listed hangers has demonstrated that this condition does not present a safety hazard because none of the welds were over-stressed."

Presently, hangers in fabrication at the supplier's plant~ being produced in accordance with Bechtel Specification 8856-M-209, Rev. 7, are of acceptable quality. We therefore conclude that additional corrective measures to preclude recurrence are not necessary.

Very truly yours, N. W. Curtis Vice President-Engineering & Construction ARS:mcb cc: Mr. J. G. Davis (15)

Acting Director-Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. G. McDonald, Director (1)

Office of Management Information & Program Control U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. Robert M. Gallo U. S. Nuclear Regulatory Commission P.O. Box 52 Shickshinny; PA 18655