ML19261D535

Deficiency Rept on 790525:piping Elbows Constructed from Unspecified Matl.Elbows W/Heat Code W6719 Were Identified, Tested & Returned to Manufacturer

ML19261D535
Person / Time
Site:	Hartsville, Phipps Bend, Yellow Creek
Issue date:	05/25/1979
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19261D530	List: ML19261D529 ML19261D535
References
NUDOCS 7906190442
Download: ML19261D535 (3)

Text

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• ' O 0 0lD HARTSVILLE NUCLEAR PIANTS A AND B PHIPPS BEND NUCLEAR PLANT .

YELLOW CREEK NUCLEAR PLANT PIPE ELBOWS MADE OF UNSPECIFIEIT MATERIAL REPORT NO. 1 (FINAL)

' NCR's HNP-A-O'47, PBNP-015, AND TCNP-007 On April 25 and May 1, 1979, TVA notified NRC-0IE Region II Inspector, M. C. Hunt, that the subject NCR's for Phipps Bend and Yellow Creek Nuclear Plants, respectively, were potentially reportable. On May 24, 1979, TVA notified Inspector T. E. Burdette that the NCR for Hartsville Nuclear Plants A and B was reportable. This is the final report on the subject NCR's.

Description of Deficiency Piping fittings made by Tube Turns Division of Cheatron Corporation (Tube Turns) and supplied to TVA by Guyon Alloys Inc. (Guyon) were fabricated from a heat of U.S. Steel SA-234 pipe in which oil drill pipe became mixed. The oil drill pipe (API-SAC) is a high strength, brittle material containing molybendium and approximately twice the carbon content of SA-234. '!be nonconforming pipe fitting. are 4-inch schedule 40 elbows designated as SMLS ASME SA-234 Grade VPB material iros heat lot V6719.

A total of 82 questionable fittings were shipped to Phipps Bend Nuclear Plant from Nov. 13, 1978, through Dec. 27, 1978. Seven of these fittings were shipped to Yellow Creek Nuclear Plant on March 1, 1979, from the stock of 52 received at the Hartsville Nuclear Plant on November 15, 1978.

Cause of Deficiency U.S. Steel, Lorain Works in Lorain, Ohio, fabricated a heat of API-5AC pipe on which the heat identity number was incorrect by one digit giving it the same heat identity number of SA-234 material. U.S. Steel set the incorrectly marked material aside for remarking. However, some or all of the incorrectly marked material became mixed with the properly marked SA-234 material. All of this material was shipped to Tube Turns marked as heat lot W6719 and was fabricated into pipe fittings.

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This situation indicates that U.S. Steel had a breakdown in the identifi-cation and control of material portion of their QA program.

Safety Implications ,

One or more of the nonconforming elbows could have been used in any safety system requiring 4-inch piping had this situation remained uncorrected. The nonconforming elbows would have a higher probability of failure due to their brittleness. This failure in combination with a single active component failure could prevent a safety system from performing its intended safety function.

Corrective Actions A memorandum was sent on May 11, 1979, from the Director of Engineering Design to all TVA nuclear plant construction sites requesting that they examine their records for receipt of material with heat code W6719, and if they find any to initiate a nonconformance report. To date, the following actions have been taken:

Hartsville Nuclear Plant The 45 elbows of heat W6719 shipped to Hartsville excluding those shipped to Yellow Creek were identified in the receiving warehouse after noti-fication by an April 3, 1979, telecon with Guyon. These elbows were listed on an OS or D (over, short, or defective) report, segregated, and shipped back to Tube Turns on April 12, 1979.

• Phipps Bend Nuclear Plant A total of 82 fittings of heat W6719 were shipped to Phipps Bend. Since three of these fittings were installed in piping assemblies in the pipe shop, U.S. Steel sent a representative to the site to check each of the fittings. On April 11, 1979, the U.S. Steel representative spark tested each of the 82 fittings onsite and found one which was made of the non-conforming material. (Note: In this spark test the spark indicates the presence of molybdenum and high carbon content, approximately 0.40 percent, in the nonconforming material and the presence of silicon and low carbon, 0.20 percent, in the SA-234 material.) The one nonconforming elbow was taken back to U.S. Steel by the representative. The other 81 elbows will be used in future piping assemblies.

Yellow Creek Nuclear Plant The seven elbove of heat W6719 were identified, placed in nonconforming status, regregated, and are awaiting shipping instructions from Hartsville.

- These elbows will be shipped back to Tube Turns. The elbows will not be used in piping at Yellow Creek Nuclear Plant. .

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Means Taken to Prevent a Recurrence Discussions have been held between representatives of TVA and representatives of Guyon, Tube Turns, and U.S. Steel since identification of the deficiency.

U.S. Steel indicated they have discussed the problem in internal QA meetings emphasizing the importance of 100 percent accuracy in material identification and control. Also, U.S. Steel representativep are investigating the situation and will prepare an internal report which will contain recournendations of any possible corrective actions which could be taken in the area of material identification and control.

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