ML20128L289

Responds to NRC Re Violations Noted in Insp Repts 50-424/85-06 & 50-425/85-06.Engineering Review of Each Individual Filler Plate Not Required.Detailed Reasons Encl

ML20128L289
Person / Time
Site:	Vogtle
Issue date:	06/13/1985
From:	Foster D GEORGIA POWER CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
GN-639, NUDOCS 8507110304
Download: ML20128L289 (4)

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Georg>a Power Compary Route 2 Box 293A Waynesboro_ Georg'a 30830 Teiephone 404 554 9901. Ext 3360 404 724 8114. Eat 1360 m

D. O. Foster [h Vice Pres 4dert and Project t% soutrern erectnc system General Manage' June 13, 1985 Vogt'e Project United States Nuclear Regulatory Commission File: X7BG10 Office of Inspection and Enforcement Log: GN-639 Region II - Suite 2900 101 Marietta Street, Northwest Atlanta, Georgia 30323

Reference:

50-424/85-06, 50-425/85-06 Attention: Mr. J. Nelson Grace The Georgia Power Company wishes to submit the following additional information in response to your letter to Mr. R. J. Kelly dated May 16, 1985, and further to our response (GN-582, dated April 16, 1985) to USNRC Inspection Report 50-424, 425/85-06.

Your letter states that our response of April 16, 1985, does not completely address the violation identified in the NRC inspection report.

The NRC Staff Assessment of Licensee Response, attached to your letter,

- states that some pipe support filler plates and their welds are subjected to tensile and shear forces and, therefore, documentation of filier plate usage is required for as-built review by engineering because the filler plates are load bearing members.

The Georgia Power Company agrees that some filler plate installations are subjected to tensile and shear forces, but it is our position that engineering review of each individual filler plate installation is not required for the following reasons:

1. Division P5 of Construction specification X4AZ01 restricts the usage of filler plates less than 3/8 inches thick tn applications where the pipe strap loads are not transmitted thsgh the filler plate material. In this configuration, shown in 6tached Figure A, the filler plate is flush with the ends of the strap and the welds transmit the strap loads directly to the support steel. The weld size is increased by the thickness of the filler plate to maintain design strength. The filler plate is exposed only to bearing loads from the pipe; therefore, the filler plate is basically being used as a shim. Additionally, the filler plate ends serve as weld backings. Since this configuration is simply a shimming operation, there is no need to produce as-built records for individual installations for engineering review.

2. Larger filler plates (from 3/8 inch to 1 -1/2 inch in thickness) are required to be installed in a different configuration as shown in Figure B. Since these filler plates extend beyond the strap 8507110304 850613 PDR ADOCK 05000424 G PDR $50 l

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Page Two ends, the filler plate material is subjected to the support loads and is basically a structural element. However, existing engineering calculations substantiate that these thicker materials are stiff enough and have sufficient section to maintain stresses within design requirements when loaded to the maximum strap capacity.

Since the filler plate design using this- configuration is substantiated by engineering analysis, as-built documentation for engineering evaluation of individual installations is not required.

Relative to the position -in the NRC Staff Assessment of Licensee Response that filler plates used in pipe supports do not come under the tolerance criteria of . paragraph P5.6.4 of specification X4AZ01, we offer the following explanation. Filler plate usage in conjunction with pipe straps was intended to be a pre-approved installation option.

Although filler plate installation, whether used in a shimming operation i or as load bearing elements, is not specifically a tolerance, it is related in the context of achieving tolerances. Since installation i- options are provided throughout the specification and are not segregated

to a specific section, there is no inconsistency in including filler

-plate installation within the " Tolerance and Limitations" section of P5.6.4. In fact, coverage of this installation option in section P5.6.4

{ 'is. appropriate since it was not intended that the usage of filler plates, in the configurations discussed earlier, require additional documentation.

Georgia Power Company acknowledged the NRC violation in our response of April 16, 1985, because we were aware, as was the NRC inspector, that some pipe strap installations using filler plates were performed outside the current limitations of specification X4AZ01 and were in l the process of identifying these installations for resolution. The

-corrective actions relative to this concern are -described in the April 16,1985, -response and are continuing accordingly. Also, the violation j was acknowledged because the engineering calculations substantiating the use of filler plates as load bearing elements were . not available on site. These calculations are now available at the site for review.

In addition, the violation and the installation discrepancies mentioned above have provided sufficient justification to conduct an extensive review of the filler plate requirements of specification X4AZ01 l

l to clarify any areas which do not provide clear direction. This review

, has already been initiated and is expected to be completed by July 31, 1985.

This response contains no proprietary information and may be placed in the NRC Public Document Room.

i Your tr ly, e

D. O. Fostq REF/DOF/tdm Attachments

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' . .i Page Thr:e xc: U. S.' Nuclear Regulatory Commission Document Control Desk Washington, D. C. 20555 R. J. Kelly J. A. Bailey G. Bockhold R. E. Conway 0. Batum P. D. Rice G. F. Head H. H. Gregory C. S. McCall (OPC)

J. T. Beckham W. T. Nickerson E. L. Blake, Jr.

R. A. Thomas D. R. Altman (Shaw, et. al.)

D. E. Dutton D. L. Kinnsch (BPC) J. E. Joiner W. F. Sanders (NRC) J. L. Vota (W) (Troutman, et. al.)

R. H. Pinson L. T. Gucwa D. C. Teper (GANE)

B. M. Guthrie C. E. Belflower L. Fowler (LEAF)

E. D. Groover F. B. Marsh (BPC) T. Johnson (ECPG)

R. W. McManus G.~A. McCarley

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I A kA t &

FIGURE A

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m FIGURE _B d.