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Engine Systems Inc. (ESI) began a 10CFR21 … Engine Systems Inc. (ESI) began a 10CFR21 evaluation on 12/20/11 upon notification of an issue with four subcover assemblies at Perry Nuclear Power Plant. It was reported that Perry was performing a maintenance activity whereby they were replacing four cylinder head subcover assemblies on their Enterprise diesel engine. During installation, it was noted that qty. 2 of 11 bolt holes were missing an upper mounting pad. This was visually apparent once the customer attempted to install the bolts, which have a 6" length. The two areas missing the upper landing pad did not have an area for the underside of the bolt head to rest upon. </br>The evaluation was concluded on 2/17/12 and it determined that this issue is a reportable defect as defined by 10CFR21.</br>DISCUSSION:</br>Lack of the mounting pads alone will not result in a failure, however if a customer attempts to install the subcover without recognizing the missing material, there is the possibility that two of the eleven hold down bolts will provide no clamping function. This may result in loosening of the subcover mounting which could allow the cover to separate from the cylinder head.</br>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 DSRV-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 (EDG). Failure of the EDG to produce its nameplate rated power could prevent the safe shutdown of the nuclear power plant during an emergency situation.</br>AFFECTED USERS AND SHIPMENTS:</br>ESI has supplied subcovers with the incorrect mounting pad to the following customers (in USA):</br>Perry; Qty: 4; Date: October 2011.</br>Note: The subcovers returned by Perry are the subject of this evaluation.</br>CORRECTIVE ACTIONS:</br>Customers may elect to justify use of a shorter bolt to facilitate installation of in-stock covers. Otherwise it is ESI's recommendation that customers return the subcovers for replacement.</br>The root cause analysis determined that the cause of this issue was that the pattern for the casting is missing the portions that would ultimately form this upper mounting pad. In addition, the machining drawing was unclear in showing these locations. As a result, ESI's inspections did not specifically check for these locations and the non-conforming subcovers were shipped to the customer.</br>The pattern is now being corrected to ensure the presence of the upper mounting pads. Also, ESI's dedication report is being revised to add specific checks to inspect for the presence of these pads. This will be completed prior to any future shipments of this item.rior to any future shipments of this item.
05:00:00, 17 February 2012 +
47,685 +
17:21:00, 22 February 2012 +
05:00:00, 17 February 2012 +
Engine Systems Inc. (ESI) began a 10CFR21 … Engine Systems Inc. (ESI) began a 10CFR21 evaluation on 12/20/11 upon notification of an issue with four subcover assemblies at Perry Nuclear Power Plant. It was reported that Perry was performing a maintenance activity whereby they were replacing four cylinder head subcover assemblies on their Enterprise diesel engine. During installation, it was noted that qty. 2 of 11 bolt holes were missing an upper mounting pad. This was visually apparent once the customer attempted to install the bolts, which have a 6" length. The two areas missing the upper landing pad did not have an area for the underside of the bolt head to rest upon. </br>The evaluation was concluded on 2/17/12 and it determined that this issue is a reportable defect as defined by 10CFR21.</br>DISCUSSION:</br>Lack of the mounting pads alone will not result in a failure, however if a customer attempts to install the subcover without recognizing the missing material, there is the possibility that two of the eleven hold down bolts will provide no clamping function. This may result in loosening of the subcover mounting which could allow the cover to separate from the cylinder head.</br>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 DSRV-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 (EDG). Failure of the EDG to produce its nameplate rated power could prevent the safe shutdown of the nuclear power plant during an emergency situation.</br>AFFECTED USERS AND SHIPMENTS:</br>ESI has supplied subcovers with the incorrect mounting pad to the following customers (in USA):</br>Perry; Qty: 4; Date: October 2011.</br>Note: The subcovers returned by Perry are the subject of this evaluation.</br>CORRECTIVE ACTIONS:</br>Customers may elect to justify use of a shorter bolt to facilitate installation of in-stock covers. Otherwise it is ESI's recommendation that customers return the subcovers for replacement.</br>The root cause analysis determined that the cause of this issue was that the pattern for the casting is missing the portions that would ultimately form this upper mounting pad. In addition, the machining drawing was unclear in showing these locations. As a result, ESI's inspections did not specifically check for these locations and the non-conforming subcovers were shipped to the customer.</br>The pattern is now being corrected to ensure the presence of the upper mounting pads. Also, ESI's dedication report is being revised to add specific checks to inspect for the presence of these pads. This will be completed prior to any future shipments of this item.rior to any future shipments of this item.
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00:00:00, 22 February 2012 +
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02:04:49, 2 March 2018 +
17:21:00, 22 February 2012 +
5.515 d (132.35 hours, 0.788 weeks, 0.181 months) +
05:00:00, 17 February 2012 +
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