Part 21 Report - 1997-160

 
 

ACCESSION #:  9701290363



FRAMATOME

TECHNOLOGIES



Integrated Nuclear Services



                              January 24, 1997

                              JHT/97-6



Document Control Desk

U.S.  Nuclear Regulatory Commission

Washington, D.C.  20555-0001



Attention:     Steven M.  Matthews (Mail Stop 9 D4)



Subject:       Final Report of Potential Safety Concern on Material Used

               for Fabrication of Permanent Canal Seal Plate



Reference:     Letter from J.H.  Taylor FTI to USNRC, "Interim Report of

               Potential Safety Concern on Material Used for Fabrication

               of Permanent Canal Seal Plate," April 5, 1996, JHT/96-30



Gentlemen:



The purpose of this letter is to provide the final disposition on the

Preliminary Safety Concern relating to the use of material constructed

with welded angles that are not allowed by ASME A479 for the permanent

canal seal plate, a safety related component.  The concern was described

in the referenced letter.



The attached evaluation is based on the examination of material test

results data.  The material properties and structural integrity of the

weld have been evaluated and determined to be satisfactory.



It is concluded that there is no significant safety hazard associated

with the continued use of the welded material for the permanent canal

seal plate during power or refueling operations at CR-3 or ANO-1.  There

is no safety concern reportable under 10CFR21 for the two affected

plants.



3315 Old Forest Road, P.O.  Box 10935, Lynchburg, VA 24506-0935

Telephone: 804-832-3000 Fax: 804-832-3663

Internet: http://www.framatech.com



If you have any questions concerning this matter, please contact the

undersigned at 804/832-2817 or Robert Schomaker at 804/832-2917.



                              Sincerely,



                              J.  H.  Taylor

                              Licensing Services



JHT/RJS/mcl



c:   WF Jones - Framatome Technologies

     LM Lesniak - Framatome Technologies



EVALUATION OF PSC 1-96



Material Certification of Angle Material for Permanent Canal Seal Plate



Introduction



Upon receipt inspection of material purchased for use as angle material

in the fabrication of permanent canal seal plates for ANO-2 (1995), a

discontinuity was noted in one leg of the angle material.  The material

was determined to be fabricated by welding a flat bar material to a

standard angle.  This process is not allowed for material certified to

ASME SA-479.  The material was rejected for use in fabrication of the

canal seal plate for ANO-2.



However, in 1992/3 a similar angle material from the same supplier was

utilized to fabricate the permanent canal seal plates for CR-3 and ANO-1.

These seal plates were classified by the customer as safety related.  The

FTI (then BWNT) subcontractor for fabrication purchased commercial grade

materials with CMTR's.  FTI (BWNT) then upgraded this material to "safety

related" and certified as such.  The fabrication of the angle material

for CR-3 and ANO -1 has also been determined to be by a welding process,

contrary to ASME SA-479 standards.



Use of the welded angles does not adversely affect safety during normal

operation.  Reliance on the welded angles may be of concern when the

permanent canal seal plate fulfills its function of retaining water in

the reactor canal during refueling activities.  This latter concern was

the basis for filing a Preliminary Safety Concern.



Discussion



Correspondence with the fabricator and material supplier documents the

TIG automated welding process used to fabricate the angle pieces.  The

flat bar is of "close chemistry" and weld wire is used in the process.



The highest stresses that the angles see are those imposed during thermal

growth of the reactor vessel when the plant is operating.  The only loads

on the angles when it is performing a safety function is the weight of

the water in the flooded canal.



In order to evaluate the structural integrity of the welded angle piece,

tests were performed on a sample angle piece at CR-3, for hardness,

chemistry, and weld geometry.  Results of the testing are documented in

reference 1.  Hardness and chemical testing of the CR-3 canal seal plate

has shown the weld material to be similar to the type 304 stainless steel

base material.  Rockwell hardness values of the weld are similar to the

base metal and chemical analysis of the weld indicate a strong match with

type 304.  It is the conclusion of FTI Welding Engineering that the seal

plate angle weld is structurally and chemically sound.



Material test results data were examined by the Mechanical and Structural

Analysis Unit of



FTI Conclusions of that examination are documented in reference 2.



Evaluation of the Safety Concern



The stresses in the angle pieces are determined to be less when

performing its safety function than during normal power operation.  The

angle pieces have already been cycled through normal operation and a

refueling at CR-s and ANO-1.  Visual inspections have already taken place

and no unacceptable indications were noted.  The material properties and

structural integrity of the weld have been evaluated and determined to be

satisfactory.  There are no questions about other materials used in the

fabrication of the permanent canal seal plate.



Conclusion



Based on the above discussion it is concluded that there is no

significant safety hazard associated with the continued use of the welded

material for the permanent canal seal plate during power or refueling

operations at CR-3 or ANO-1.  There is no safety concern reportable under

10CFR21 for the two affected plants.



References



1.   FTI Document 51-1254895-00,01, "CR-3 Seal Plate Test Results",

     10/29/96 and 1/9/97.



2.   FTI Document 51-1258586-00, "CR-3 Seal Plate Stress Analysis

     Validation", 1/13/97.



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