ENS 44445

v t e ENS Event
05:00 Aug 28, 2008
Title	Replacement Diaphragm Failures Due Inadequate Cure and Operation Over Maximum Pressure
Event Description	Fisher was recently notified by Luminant, Comanche Peak SES of two replacement diaphragm failures. These diaphragms had been in service for approximately 3.1 years. The diaphragms lost frictional flange retention in a progressive type failure which transferred retention stress to the bolt/diaphragm interfaces and caused localized stresses great enough to initiate rupture. Rupture propagation occurred catastrophically in multiple directions and rapid loss of actuator pressure resulted and consequently, opening of the valve. This is applicable to all Fisher size 80, type 657 and 657NS sliding stem valve actuators sold to the nuclear industry by Fisher Controls International LLC that are equipped with nitrile/nylon diaphragms (Fisher part number 1R6375X0072). It is unknown what plants in addition to Comanche Peak are affected by this report.

ENS 44445 +/-
Where
Fisher Controls International, Llc Marshalltown, Iowa (NRC Region 3)
Organization:	Emerson Process Management
Reporting

10 CFR 21.21
Time - Person (Reporting Time:+8.8 h0.367 days <br />0.0524 weeks <br />0.0121 months <br />)
Opened:	Matthew Farrell 13:48 Aug 28, 2008
NRC Officer:	Jason Kozal
Last Updated:	Aug 28, 2008
44445 - NRC Website
v • d • e

v t e Emergency Notification System
Fisher Controls International, Llc with 10 CFR 21.21, Notification of failure to comply or existence of a defect and its evaluation
WEEKMONTHYEAR2008-08-28T05:00:00 [Table view]
[ENS list for Fisher Controls International, Llc]

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