ML20064D247

Interim Rept of Significant Deficiency 9 Re Noncompliance W/ Weld Requirements for HVAC Seismic Support Hangers to Embedded Plates & Lack of Preheating

ML20064D247
Person / Time
Site:	Waterford
Issue date:	09/29/1978
From:	LOUISIANA POWER & LIGHT CO.
To:
Shared Package
ML20064D211	List: ML20064D208 ML20064D247
References
NUDOCS 7811010033
Download: ML20064D247 (4)

Text

.,

4 u

LOUISIANA POWER & LIGHT COMPANY WATERFORD SES - UNIT No. 3 1.

F INTERIM REPORT OF SIGNIFICANT DEFICIENCY NO. 9 REPORT OF NONCOMPLIANCE TO WELDING REQUIRDENTS FOR HVAC SEISMIC SUPPORT HANGER TO EMBEDDED PLATES I

l l

l l

l

\

l September 29, 1978

.7) '

• • Wf \ {

.w ,

Pags 1 Introduction This report is submitted pursuant to 10CFR50.55(e). It describes deficiencies with regard to the welding of HVAC Seismic Support Hangers to Embedded Plates at Waterford Unit 3.

Background

As a result of a review of the American Welding Society - Structural Welding Code, it has been determined that 425 HVAC seismic support hangers at the Waterford 3 Steam Electric Station have been welded to embedded plates with-out applying the required preheat to the plates. The welding was performed by The Waldinger Corporation at various elevations in the Reactor Auxiliary and Fuel Handling Buildings utilizing E-6011 series electrodes. As identified in the Struerural Welding Code - AWS Dl.1-75, metals with a thickness over 3/4" to 1-1/2" must be preheated to 150 degrees F when an E-60XX series electrode is used.

A "Stop Work Order" was issued by Ebasco Management on June 19,1978, on the l use of E-60XX series electrodes.

1 Mr. A.E. Henderson of Louisiana Power & Light Company, 142 Delaronde Street, New Orleans, Louisiana, notified Mr. R.C. Stewart of the NRC on July 11, 1978, of this potential significant construction deficiency.

The "Stop Work Order" was rescinded on June 20, 1978, upon review of Waldinger's revised welding inspection and installation procedures. Shielded metal are welding of the HVAC support hangers to the embedded plates resumed utilizing only E-7018 serias electrodes (per procedure).

Ebasco Quality Assurance initiated Nonconformance Report W3-957 on June 20, 1978, describing the deficiency.

Discussion On June 16, 1978, upon review of the American Welding Society - Structural l Welding Code AWS 01.1-75, it was determined that 425 HVAC duct seismic support l $ hangers at Waterford 3 Steam Electric Station were welded to embedded plates -

(1 inch to 1-1/2 inch thick) without applying preheat to the plate as required by the Code. The 425 seismic supports, material specification ASTM A36, are located at various elevations in the Reactor Auxiliary Building (402 supports) and the Fuel Handling Building (23 supports) as identified in attachments to Nonconformance Report W3-957. The welding was performed by The Waldinger Corporation, the HVAC Contractor, utilizing E-60ll series electrodes as iden-tified in their Weld Specification No. PQW-1. In accordance with Structural Welding Code AWS Dl.1-75, ASTM A36 metals with a thickness of over 3/4 inch to 1-1/2 inch must be preheated to 150 degrees F when an E-60KX series elec-trode is used.

Failure to preheat these plates is a direct violation of the HVAC Contractor's Weld Specification No. PQW-1 and Structural Welding Code AWS Dl.1-75.

Pega 2 At the time of discovery of this deficiency, overall construction of Waterford 3 was 44.6 percent complete and the HVAC seismic support in-stallation in the Reactor Auxiliary Building and Fuel Handling Build-ing was 41 percent and 32 percent complete, respectively.

ANALYSIS OF SAFETY IMPLICATIONS As of this writing, this deficiency is classified as reportable be-cause of the extensive engineering evaluation needed to determine the significance of the deficiency under 10 CFR 50.55(e). This deviation is a departure from the technical requirements of AWS Dl.1-75. If the current engineering evaluation determines that the HVAC seismic support welds are defective, a major degradation of essential safety related HVAC equipment (e.g. , Control Room Air Conditioning System, Controlled Ventilation Area System) could result during a seismic event if the identified welds are left uncorrected.

CORRECTIVE ACTION To prevent recurrence of this deficiency on an immediate and long term basis, the HVAC Contractor has revised his Weld Specification No. PQW-1 and Structural Support Ranger Field Work Procedure No. FWP 7.2-1 to allow only the use of E-7018 series electrode for the hanger to embedded plate weldment. The Contrattor has also revised his Inspection Procedure FQCP 10.2-3 to provide a ' check point" for preheat prior to welding.

A limited Stop Work Order is in effect regarding weldments to materials with thicknesses over 1-1/2 inch. As identified in the limited Stop Work Order:

No weldments to material in excess of 1-1/2 inch will be allowed until an approved welding precedure has been developed delineating preheat parameters as specified in AWS D1.1-1975.

In order to establish a basis for the acceptability of weldments on the

- 425 HVAC seismic support hangers described in this report, the following investigation and qualification testing will be performed:

1) Macro-Etching Tests on Representative Welds The Ebasco Materials Applications Department is in the process of selecting Longitudinal - Bead ald - Underbead - Cracking Test Samples as a basis for evaluating the severity of the problem.

This test approach was developed by the Battelle Memorial Institute and is a widely accepted method for testing the sensitivity of steels to underbead cracking.

In order to provide results which would prove the acceptability of all of the heats of materials involved, Ebasco Materials Applications is procuring various heats of material with chemistry and carbon equiva-lents representative of the upper to .45 range of carbon equivalencies permitted by ASTM Specification A-36.

• Page 3

2) Magnetic-particle Testing (MT) of Existing Welds A program is currently being developed to perform and evaluate mag-netic particle tests on in-place HVAC seismic supports. The tests will be performed in accordance with requirements to be established and documented by the engineer (Ebasco).

Based on the conclusions obtained from evaluations of the above tests, and any further investigations or tests and/or corrective action which may be required, this section of the report will be updated in the final report to be issued on or before December 31, 1978.

l l

e

, - - - - - - y . . , - _ - - ,,,.--..-r- - - . . , - -