Sepon POX 2 Mechanical Seal System Failure Investigation

Summary

CJ Galeotti June 2014

What Happened?

2

•  Apparent Causes •  At approximately 1630hrs on 16th June 2014, the POX 2 autoclave was

shutdown on ESD due to high flow differential on the seal cooling system. •  Operations confirmed failure of AG205 (compartment 1), •  Duty Charge pump PU-488 was not maintaining system pressure for 12+hours

due to blocked inlet strainer •  Standby Charge Pump PU-487 was in manual and therefore would not

automatically start in response to system pressure

•  Underlying Causes •  Control logic not configured to override manual status on standby pump •  Alarm was not at sufficient level to alert operator to seal pressure condition •  Present process of filling Barrier Fluid tank allows entry of contaminants •  Lack of routine PM to service and inspect functional operation of Seal Support

system

POX 2 Seal System

3

What Happened? Further detail

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•  Upper Seal •  Stationary ring shattered, running face scored, it is suspected that this

failed @1207hrs on 16th June, venting seal chamber to atmosphere

What Happened? Further detail

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•  Lower Seal •  Stationary ring radial crack though

locating hole, running surfaces OK.

POX 2 Seal System

6

Other Items

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•  Accumulators discharged •  Seal Bearing defects •  Seal water system build-up

in pipes

RCA Actions

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Cause Ac)on Status DueDate FollowUpUser

Sealsystempressurelessthanautoclavepressurefor16hourspriortofailure Pressuretestremainingseals Complete 22-Jun-14 CraigHyaD

PumpPU-488suc)onstrainerblocked Flushoutandinspectcharging,circula)onandflushingsystemsonsealwaterskid,includingpipes,pumpsandfilters. Complete 22-Jun-14 AndrewDavid

Williams

PumpPU-488suc,onstrainerblocked Checktoseeifaccumulatorcanbere-charged.Re-chargeifOK Complete 22-Jun-14 AndrewDavidWilliams

NoPMforen)reSealSystemSkid DevelopaPMforthePOX2SealSystemsuchthatallelementsareinspectedandverifiedasopera)ngtoarequiredspecifica)on.ThefrequencyofthePMshouldbesetini)allytoatleast3months. Started 31-Jul-14 CJGaleoV

NoPMforen,reSealSystemSkid AddallMechsealbearingloca,onstoConMonvibra,onroute Started 26-Jun-14 CJGaleoN

Processofaddingglycerintosystemallowscontaminantstoentertank

Forthepresentsystem,installafilteronthemanualpumpusedtotopuptheBarrierfluidtanktopreventcontaminantsfromenteringinthefirstplace. Started 11-Jul-14 CraigHyaD

Processofaddingglycerintosystemallowscontaminantstoentertank

IncludeinSealSystemreview,theneedtohaveaimprovedsystemforstorageanddispensingofbarrierfluid Started 30-Jun-15 CJGaleoV

ControlSystemlogicdoesnotsupportoverrideofmanualstatus

ReviewControlsystemlogic,alarmandsetpointsforMechsealsupportskidinlinewithWCISnotesandM.Day'sobserva)ons.Ac)onshouldinclude:star)ngofstandbypumpandtheabilitytorevertittoautoifdutypumpcannotmaintainopera)onalparameters

Started 09-Jul-14 CJGaleoV

Anonaudiblecategory2Alarmwasgenerated Addalarmtosystemthatcon)nuestoAlertOperatorifSealpressurefallsbelowasafevalue Started 08-Jul-14 CJGaleoV