ML17032A080

Engine Systems, Inc., 10CFR21 Reporting of Defects and Non-Compliance, Report No. 10CFR21-0114, Rev. 0

ML17032A080
Person / Time
Site:	Perry, Vogtle
Issue date:	12/30/2016
From:	Woolard S Engine Systems
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
10CFR21-0114
Download: ML17032A080 (6)

Text

ENGINE SYSTEMS, INC. 175 Freight Road Rocky Mount, NC 27804 December 30, 2016 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Telephone: 252/977-2720 Fax: 252/446-1134

Subject:

1 OCFR21 Reporting of Defects and Non-Compliance -Engine Systems, Inc. Report No. 10CFR21-0114, Rev. 0 Subcover Assembly, P/N 1A-7846

Dear Sir:

The enclosed report addresses a reportable notification of an Enterprise emergency diesel generator subcover assembl, P/N 1A-7846 .. A copy of the report has been mailed to our affected nuclear customers. Please sign below, acknowledging receipt of this report, and return a copy to the attention of Document Control at the address above (or, fax to number 252/446-1134) within 10 working days after receipt. Yours very truly, ENGINE SYSTEMS, INC. Susan Woolard Document Control Please let us know if ANY of your mailing information changes -name of recipient, name of company/facility, address, etc. Mark the changes on this acknowledgment form and send to us by mail or FAX to the number above. RECEIVED:---------93 DATE: Quality Performance With Pride

Report No. 1 OCFR21-0114 Record of Revisions Page: 1 of 1 REV DATE PAGE DESCRIPTION 0 12/28/16 Initial issue.

COMPONENT: Subcover assembly, P/N 1A-7846. SUMMARY: Report No. Revision: Date: Page: 10CFR21-0114 0 12/28/16 1 of 3 Engine Systems Inc. (ESI) began a 1 OCFR21 evaluation on November 18, 2016 upon notification of an issue with a subcover assembly at Perry Nuclear Plant. Attempts to install the subcover on their Enterprise diesel engine revealed two issues that prevented successful installation. First, one of the bolt holes was not fully machined through the entire depth of the subcover. Though the bolt could be inserted into the top of its corresponding hole, it would not pass completely through. The second issue was an interference between the rocker arm shaft and its mating pedestal. It was found that incomplete machining of the pedestal prevented the shaft from sitting flat on the pedestal. The evaluation was concluded on 12/21 /16 and it was determined that this issue is a reportable defect as defined by 1 OCFR21. The figures and photos below and on the following page provide visual detail of the deficiencies. Item #2: Location of incomplete machining of pedestal Item #1 : Location of inadequately drilled bolt hole Figure 1: Outline Drawing of Subcover Item #2: Photo 1: Visual Depiction of Inadequately Drilled Bolt Hole Correct Machining (note radius) Figure 2: Ideal Pedestal Machining CC.TAlL 'Y' Report No. Revision: Date: Page: 1 OCFR21-0114 0 12/28/16 2 of 3 Photo 2: Attempted Bolt Install Photo 3: Actual Machining DISCUSSION: Report No. Revision: Date: Page: 10CFR21-0114 0 12/28/16 3 of 3 The subcover is a device that is fastened to the top of the cylinder head and provides support for the rocker arms and rocker shafts and encloses the valve stem area. There is one subcover per cylinder head and thus for a model OSRV-16-4 Enterprise engine there are 16 subcovers. Failure of a subcover would impact the ability of either of the corresponding rocker arms to provide the mechanical force to actuate the intake and exhaust valves. Without valve actuation, that particular power assembly would be unable to generate power which would reduce the output of the emergency diesel generator (EOG). Failure of the EOG to produce its nameplate rated power could prevent the safe shutdown of the nuclear power plant during an emergency situation. The issue regarding the inadequately drilled bolt hole would be detected during installation since it would prevent the bolt from passing through the hole. Therefore, it is determined this issue would have no impact on operability since the cover could not be installed with an incompletely drilled bolt hole. With regard to the incompletely machined pedestal, there is the potential that a customer could install the rocker arm shaft without detecting this issue. In this situation, the shaft will partially fit on the pedestal and the bolt will thead into subcover; however, the shaft will not seat fully on the pedestal. This prevents full contact with the pedestal and inhibits adequate preload throughout the bolted joint. If a customer were to install the rocker arm shaft (with mating rocker arms, pushrods, etc) onto the engine without realizing this issue, operability and durability of the engine would be compromised. This could present a substantial safety hazard. AFFECTED USERS AND SHIPMENTS: All of the subcovers listed below are subject to the pedestal machining discrepancy and may subject to the inadequately drilled bolt hole. ESI Sales Order Order Date Customer Customer PO Quantity ESI Certification Shiooed Date 8001930 12/19/2011 First Energy -Perry 45307431 4 1/30/2013 (qty 1) (AFW#3168) 7/27/2013 (qty 3) 3006881 (qty 14) 2/4/2010 Korea -Yonggwang Y090528171 15 7/27/2013 (qty 14) 8001963 (qty 1) 10/18/2013 (atv 1) 3009694 2/23/2012 Korea -Yonggwang NY G 1-02 MOOO 7 -550 2 7/27/2013 3009847 4/5/2012 First Energy -Perry 45389292 8 7/27/2013 (qty 5) 9/27/2013 (qty 3) 3009695 2/23/2012 Korea -Yonggwang Y050089101 2 10/18/2013 3015101 12/29/2015 Georgia Power -Vogtle SNG10122963 2 4/21/2016 CORRECTIVE ACTIONS: Customers may elect to perform corrective machining to restore the subcover to its design dimensions. Otherwise, return the affected subcovers to ESI for inspection and rework. If customer rework is desired, perform the following: a) Inspect for the bolt hole (item #1 ). If rework is necessary, drill through to a diameter of 13/16". b) For the incomplete machining of the rocker arm pedestal (item #2), first remove the installed dowel which has 0.000" to 0.001" clearance. Then machine a 2" radius relief at the affected area. All other dimensions such as pedestal height shall remain unchanged. The root cause analysis determined the cause to be machining errors that were not detected during ESl's dedication activities. As subcovers are returned, they will be re-machined at the vendor's facility, inspected by ESI, and returned to customers within 60 days of receipt. ESI will also incorporate revisions to the dedication report prior to the supply of any new or reworked subcovers to further clarify the inspection of these features during the dedication process, thereby preventing reoccurrence.