ML20072C507

Final Significant Const Deficiency Rept 61 Re Linear Crack in SA213 Stainless Steel Tubing.Initially Reported on 820831.Defects Result of Processing Rather than Metallurgical Composition.Vendor QA Program Improved

ML20072C507
Person / Time
Site:	Waterford
Issue date:	03/01/1983
From:	Maurin L LOUISIANA POWER & LIGHT CO.
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
10CFR-050.55E, 10CFR-50.55E, W3I83-0068, W3I83-68, NUDOCS 8303080461
Download: ML20072C507 (8)

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k, b lf k___(?k t f, LOUISIANA 242 onAnoNoe sincer Y POWER & LIGHT P O BOX 6008 NEW OnLEANS. U IJIS'IANA 70174 * (504) 366-2345

$?0$EsE March 1, 1983 t. v. MAunin Vice President Nuclear Operations W3183-0068 Q-3-A35.07.61 Mr. John T. Collins, Regional Administrator Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012

SUBJECT:

Waterford SES Unit No. 3 Docket No. 50-382 Significant Construction Deficiency No. 61 "Lineer Crack In Stainless Steel Tubing" Final Report

REFERENCE:

LP&L letter W3I82-0021 dated August 31, 1982, L. V. Maurin to John T. Collins

Dear Mr. Collins:

In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Final Report of Significant Construction Deficiency No. 61,

" Linear Crack In Stainless Steel Tubing."

If you have any questions, please advise.

Very truly yours, i $h/

L. V. faurin LVM/ MAL:keh cc: 1) Director 3) E. L. Blake Office of Inspection & Enforceme.mt U. S. Nuclear Regulatory Commission Washington, D. C. 20555 (with 15 copies of report)

2) Director 4) W. M. Stevenson Office of Management Information and Program Control U. S. Nuclear Regulatory Commission Washington, D. C. 20555 (with I copy of report) h 8303080461 830301 gDRADOCK 05000382 PDR

FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 61 LINEAR CRACK IN STAINLESS STEEL TUBING INTRODUCTION

This report is submitted pursuant to 10CFR50.55(e). It describes defects in 1/2" diameter stainless steel tubing SA213 Type 316. This tubing has been installed in some instrumentation lines at Louisiana Power & Light Company Waterford No. 3 This problem is considered reportable under the requirements of 10CFR50.55(e).

To the best of our knowledge, this problem has not been identified to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION Mercury Company of Norwood Incorporated discovered a 1 1/4 inch long defect (crack) which exhibited several branches during attempts to pressurize the line to instrument PT-RC-0173 for Hydrostatic Test M-262 on the reactor vessel coolant instrument lines. This through wall defect was found in the 1/2" diameter stainless steel tubing material manufactured by Sandvik Corporation of <

l Scranton, Pennsylvania.

The defective tube was sectioned and subjected to macroscopic and liquid i

penetrant examinations by Ebasco Services Incorporated. A second defect which i did not penetrate the tube wall was found on the-tube ID surface approximately 8 I

inches from the through wall defect. This defect and the through the wall defect appeared to be manufacturing related and because of the safety class of the material Sandvik's manufacturing personnel were informed of the problem.

Based upon a metallurgical investigation conducted by Ebasco Services and Sandvik Corporation, the following conclusions were reached:

1. The chemical analyses and metallurgical samples indicate that the material complies with the requirements of SA 214 Type 316 with respect to composition, ferrite content, nonmetallic inclusion content and l distribution. The analyses also indicates that no mixing of material heats occurred.

2. The cause of the defects was localized overheating of the billet material prior to extrusion of the tube hollow. This localized overheating resulted in partial melting and cracking of the billet material. During subsequent extrusion and cold forming operations the defective area was elongated resulting in the defects found in the material installed at the site.

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3. Defects such as the two (2) found in the Waterford 3 Instrumentation Tubing caused by hot metal tears usually are of sufficient depth and exhibit such characteristic abruptness and raggedness as to be detectable by eddy current testing. This through wall defect should have been detected during production by hydrostatic testing.

4. The production documentation for Heat 466023 Work Order 41952, which contained the defective tube, showed no rejects for hydrostatic testing

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(2500 psi on 5/9/81) or eddy current testing (performed on 5/11/81). Due to these facts the tube material from the suspect heat and work order were not considered to have been adequately tested for integrity.

l SAFETY IMPLICATIONS Tubing from Heat No. 466023 Work Order 41952 has been installed in the Reactor Coolant, Safety Injection, Emergency Diesel Generator System and other Safety Related Systems in which ASME Section III and B31.1 are applicable. These systems include Class IE instrument installations. Failure of a tube from this heat of material installed in a Class IE instrument loop may result in an inability of the loop to perform its safety function. Therefore, corrective action described herein is required for safe operation and shut down of the plant.

l CORRECTIVE ACTION i

Sandvik's metallurgical analysis of the defective material concluded that the defects were the result of a processing rather than a metallurgical composition problem and were localized in one (1) tube. An analysis and statistical review of the NDE failure rate at Sandvik's facilities was performed by Ebasco Quality Assurance and found to be acceptable.

As a result of this incident, Sandvik's quality program at Scranton, Pennsylvania was further strengthened to guard against a possible reoccurrence by upgrading the Q.A. Program from information developed from internal investigation of this incident.

All tubing with Heat No. 466023 installed at Waterford III has been identified, hydrostatically tested to meet ASME SA213 and SA450 where required per Ebasco's Engineering disposition.

Nonconformance Reports W3-3919 and W3-4014 were initiated to track, document and control the disposition for corrective cetion. Corrective action is completed and all documentation for Nonconformance Reports W3-3919 and W3-4014 have been reviewed, accepted and closed.

This report is submitted as the Final Report.

4 FINAL REPORT SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 61 LINEAR CRACK IN STAINLESS STEEL TUBING INTRODUCTION This report is submitted pursuant to 10CFR50.55(e). It describes defects in 1/2" diameter stainless steel tubing SA213 Type 316. This tubing has been installed in some instrumentation lines at Louisiana Power & Light Company Waterford No. 3 This problem is considered reportable under the requirements of 10CFR50.55(e).

To the best of our knowledge, this problem has not been identified to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION Mercury Company of Norwood Incorporated discovered a 1 1/4 inch long defect (crack) which exhibited several branches during attempts to pressurize the line to instrument PT-RC-0173 for Hydrostatic Test M-262 on the reactor vessel coolant instrument lines. This through wall defect was found in the 1/2" diameter stainless steel tubing material manufactured by Sandvik Corporation of Scranton, Pennsylvania.

The defective tube was sectioned and subjected to macroscopic and liquid penetrant examinations by Ebasco Services Incorporated. A second defect which did not penetrate the tube wall was found on the tube ID surface approximately 8

! inches from the through wall defect. This defect and the through the wall I defect appeared to be manufacturing related and because of the safety class of the material Sandvik's manufacturing personnel were informed of the problem.

Based upon a metallurgical investigation conducted by Ebasco Services and Sandvik Corporation, the following conclusions were reached:

1. The chemical analyses and metallurgical samples indicate that the material complies with the requirements of SA 214 Type 316 with respect to composition, ferrite content, nonmetallic inclusion content and distribution. The analyses also indicates that no mixing of material heats occurred.

2. The cause of the defects was localized overheating of the billet material prior to extrusion of the~ tube hollow. This localized overheating resulted in partial melting and cracking of the biller material. During subsequent extrusion and cold forming operations the defective area was elongated resulting in the defects found in the material installed at the site.

l

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( 4* .

[

t 3. Defects such as the two (2) found in the.Waterford-3 Instrumentation Tubing caused by hot metal tears usually are of sufficient depth and exhibit such characteristic abruptness and raggedness as to be detectable by eddy current testing. This through wall defect should have been detected during production by hydrostatic testing.

l 4. The production documentation for Heat 466023 Work Order 41952, which l contained the defective tube, showed no rejects for hydrostatic testing j (2500 psi on 5/9/81) or eddy current testing (performed on 5/11/81). Due i to these facts the tube material from the suspect heat and work order were I not considered to have been adequately tested for integrity.

SAFETY IMPLICATIONS Tubing from Heat No. 466023 Work Order 41952 hcs been installed in the Reactor

( Coolant, Safety Injection, Emergency Diesel Generator System and other Safety Related Systems in which ASME Section III and B31.1 are applicable. These systems include Class IE instrument installations. Failure of a tube from this

! heat of material installed in a Class 1E instrument loop may result in an inability of the loop to perform its safety function. Therefore, corrective i action described herein is required for safe operation and shut down of the plant.

l l CORRECTIVE ACTION Sandvik's metallurgical analysis of the defective material concluded that the defects were the result of a processing rather than a metallurgical composition problem and were localized in one (1) tube. An analysis and statisticci review of the NDE failure rate at Sandvik's facilities was performed by Ebasco Quality Assurance and found to be acceptable.

As a result of this incident, Sandvik's quality program at Scranton, Pennsylvania was further strengthened to guard against a possible reoccurrence by upgrading the Q.A. Program from information developed from internal investigation of this incident.

All tubing with Heat No. 466023 installed at Waterford III has been identified, hydrostatically tested to meet ASME SA213 and SA450 where required per Ebasco's Engineering disposition.

Nonconformance Reports W3-3919 and W3-4014 were initiated to track, document and control the disposition for corrective action. Corrective action is completed and all documentation for Nonconformance Reports W3-3919 and W3-4014 have been reviewed, accepted and closed.

This report is submitted as the Final Report.

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