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# OAR Box 1778 Prepped by Ollie Stewart



## Document

Number: 

# 223 ) 11-1- 3 Docket Number: 

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Sheet 223 of 276P. 2

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W . C . BECKJOR D STATION-UNI T 3 TH E FIRS T FUL L IMPLEMENTATIO NO F LIF E EXTENSIO

NRECOMMENDATION S

Barr yE . Pulskam

p ^.A w Cincinnat i Ga s & Electri c Compan y 

# r€i3

- V 3 

# A ' ^ X

ABSTRACT Agrea t man

yutilitie s acros s th e countr

yhav e include d Lif e Extensio n a s a n integra l par t o f thei r generatio n expansio n plans . Lif e Extensio n ha s temporaril yreplace d ne wconstruction . Mos t o f thes e utilitie s hav e adopte d a "phased " approac ht o Lif e Extensio n o f candidat e units . Th e Cincinnat i Ga s & Electri c Company' s W . C . Beckjor d Station-Uni t 3 i s the firs t generating uni t i n the countryt o complet e a "full " instea d o f "phased " lif e extensio n program . During a thirtee n wee k outag e whic hended in January , 1986 , al l lif e extensio n modification s recommende d a s a resul t o f extensiv e studie s wer e implemented . Atota l o f forty-nin e replacemen t and/o r modificatio n project s wer e performe d t o ad d approximatel y2 5 year s t o th e unit' s lif e a t a tota l cos t o f les s than SlOO/kW . The planning , coordinatio n an d projec t managemen t utilize d t o inspec t an d evaluat e th

e conditio n o f the unit , procur e materials , equipment , an

d contractor s an

d complet e th

e installatio n an

d startu

p ar e discusse d in detail . BACKGROUN

D *•" . C . Beckjor d Statio n i s locate d or . th e Ohi o Rive r nea r Ne wRichmond , Ohio , approximatel y1 7 mile s upstrea mfro mCincinnati , Ohio . Uni t 3 ha s a rated capacit yo f 12 8 MW an d wa s place d int o servic e i n 1954 . The uni t consist s o f _.&. * fron t fired singl e rehea t pulverize d coa l boile r an d a Genera l Electri c tander . compoun

d two flowturbine . Stea mcondition s ar e 180 0 psig/100 0 deg . F/100 0 deg . F . The uni t wa s conservativel ydesigned , well-built , an d ha s bee n well

maintained . It s hea t rate s an d availabilit yhav e bee n favorable . A n analysi s o f CGkE' s generatio n expansio n plan identifie d Uni t 3 a s th e prime candidat e fo r lif e extension .

STUDIE S Fo r thirt yyears , the plan t operators , maintenanc e an d othe r suppor t personnel 1 have worke d wit hthe unit . The yknowi t well ; the ykno wit s limitation s an d it s strong points . Theyhave a goo d idea o f wha t equipmen t i s o r i s no t suitabl e fo r anothe r twenty-fiv e years . Thi s knowledg e i s a valuabl e sourc e o f ir.forr.ation . I n ou r studies , i t va s use d t c buil d the foundatio n fo r our

ilP. 3

detaile d investigations . I t allowe d u s to focu s our resource s o n specifi c areas . Ou r preliminarystudie s ha d estimate d a cos t o f S89/ki . t o exten d th e lif e c f Uni t 3 . On e o f the mos t questionabl e area s in th e determinatio n o f remaining lif e i s turbine-generators , especiall yrotor s an d shells . W e realize d tha t thi s equipmen t i s highl yengineere d an d tha t muc ho f th

e informatio n require d t o properl yevaluat e thi s equipmen t i s proprietaryb yth e manufacturer , Genera l Electric . I n th

e cas e o f Uni t 3 , Genera l Electri c had bee n involve d i n ever y turbin e overhau l sinc e th e initia l startup . Fo r thes e reasons , G E wa s contracte d t o perfor ma lif e extensio n evaluatio n o f the turbine-generato r equipment . Thi s stud ywa s initiate d i n Septembe r o f 1983 , an d complete d i n February , 1984 . Th e G E stud

yo f the turbine-generato r supporte d our origina l estimate . Managemen t approva l wa s obtaine d in June , 1984 , t o procee d wit hlif e extension . Athirtee n wee k outag e wa s schedule d fo r th e fal l o f 1985 . Atea m wa s assemble d t o investigat e th e remaining area s o f the unit . Organizatio n o f th e stud ytea mi s show

n i n Figur e 1 . Th e Boile r Plan t stud y wa s conducte d b

you r in-hous e engineering personne l wit hassistanc e i n the evaluatio n o f hightemperatur e component s fro mBabcoc k & Wilcox . Electrica l equipmen t an

d structure s wer e als o evaluate d b yin-hous e personnel . Bechte l Associate s wa s contracte d t o perfor mth e lif e extensio n evaluation s o f balanc e o f plan t equipment . Bechte l wa s responsibl e fo r basicall yal l othe r equipmen t no t supplie d b

yeithe r th

e origina l boile r o r turbin e contracts . Thes e studie s wer e formall ykicke d of f in July , 1984 , an d wer e complete d i n February , 1985 , a s scheduled . Thi s demanding schedul e wa s complicate d b yth e nee d t o conduc t the inspectio n during a two-wee k period . Thi s require d specia l consideration s an d carefu l planning . Th e inspectio n wor k wa s carefull ystage d an d schedule d s o tha t th e uni t coul d be returne d to servic e withi n 2 4 hour s notic e i f require d fo r load . SCOP E O F WORK A s a resul t o f th

e study , 4 9 capita l improvemen t project s wer e identifie d for th e lif e extensio n outage . CG& E define s capita l project s i n accordanc e wit h Federa l Energ

yRegulatoryCommissio n guidelines . Alis t o f thes e refurbishmen t project s i s provide d in Tabl e I .

AMAJO R PROJEC T WITH AMINOR SCHEDUL E At the tim

e o f our inspections , th e outag e t o implemen t th e recommendation s o f thos e inspection s wa . les s than one yea r away . Actio n ha d t o be take n t o expedit e procuremen t o f lon g lea d tim e items . Ou r requirement s for obtaining competitiv e pricing coul d no t be compromise d and , befor e w e coui d procee d wit h an ypurchase , our evaluatio n an d ccs t justificatio n for th e replacemen t o r modificatio n ha

d to be approved . I t wa s obvious , tha t in orde r t o maintai n our commitmen t t o th e outag e schedule , we mus t utiliz e som e o f th e projec t control s normall yreserve d fo r major , newconstructio n projects .P. 4

WCB- 3 Lif e Extensio n Capita l Wor k Turbin e Relate d Bucke t Replacemen t ( 5 row? ) Stea m Sea l Conversio n K P Inne r Shel l Replacemen t Stati c Excite r Sto p Valv e Bypas s Valv e Installatio n Generato r Fiel d Rewin d Generato r Stato r Rewin d Starting & Loading Thermocouple s Misc . Contro l Improvement s Condense r Retubing Fin e Mes hScreen s Boile r Relate d Bunke r Replacemen t I D Fan Driv e Replacemen t Demineralize r Replacemen t Combustio n Control s Servic e Wate r Piping Replacemen t Wate r Sampling Room Annunciato r Replacemen t Boile r Ski n Casing Insulatio n Replacemen t Ignito r Replacemen t Feede r Moto r Replacemen t 'Secondar

yAi r Damper s PrimaryAi r Fan Replacemen t Sootblower s Replacemen t Secondar

ySuperheate r HighTemp . Header s (3 ) PrimaryReheate r Secondar

yReheate r Uninterruptibl e Powe r Suppl y Misc . Contro l an

d Pane l Equipmen t

Tota l Projec t cos t approximatel y513,000,000 , including al l engineering , overheads , an

d allowanc e fo r funds .

Tabl e I

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We ha d recentl yacquire d th e PREMI S critica l pat hmetho d scheduling program . I n the past , o n majo r projects , ou r scheduling wor k ha d alway s bee n handle d b y outsid e consultants . A s soo n a s w e wer e abl e t o identif ya potentia l replacemen t o r modificatio n fo r the outage , actio n wa s take n t o inpu t th e schedul e int o th

e PREMI S program . Ou r primar yconcern s a t thi s poin t wer e to : 1 . Orde r an

d receiv e al l material s an d equipmen t prio r t o th e firs t da

yo f the outage , an d 2 . Complet e al l engineering an d drafting in tim

e t o allo wfo r obtainin g competitiv e bids , an d 3 . Awar d installatio n contract s i n tim e t o allo wcontractor s t o prepar e detaile d installatio n schedules . On thi s project , ou r plan s wer e t o complet e al l engineering in-hous e fo r capita l projects . Man yo f ou r engineering personne l wer e unfamilia r wit h th e PREMI S program . T o expedit e the inpu t o f information , standar d form s wer e prepare d tha t liste d th e norma l step s i n th e engineering-procurement-drafting proces s i n ou r company . Th e enginee r simpl yha d t o fil l i n the estimate d tim e t o complet e eac hstep i n th e proces s and/o r fi x th e dat e whe n th

e step ha

d to be complete . Thes e form s greatl ysimplifie d th e schedul e formatio n process . Onc e the PREMI S schedule s wer e input , th e critica l path s wer e identifie d an d w e wer e abl e t o concentrat e ou r effort s o n thos e items i n trouble . CONTRACTOR S I t ha s bee n ou r experienc e tha t th e fewe r contractor s o n th e jobsite , th

e easie r i t i s t o contro l the project . Limiting th e contractor s als o limit s th e "finger-pointing " an d simplifie s coordination . Fo r thi s project , installatio n contractor s wer e chose n fo r the following wor k packages : Turbine-Generato r Boile r Electrica l Piping Condense r Asbesto s Remova l Insulatio n Beside s th

e capita l wor k involve d in th e lif e extensio n project , ther e wa s a larg e amoun t o f maintenanc e wor k identifie d b ythe plan t tha t had t o b e include d i n the wor k packages . Thi s require d a clos e workin g relationshi p betwee n engineerin g an d plan t personne l relate d t o the outage . Th e turbine-generato r installatio n contrac t wa s awarde d t o Genera l Electric . Muc ho f thi s work , especiall yservic e sho p work , wa s awarde d o n a fir mpric e basis . Lat e i n the outage , problem s wer e foun d wit hth

e stato r winding s in th e generator . Nationa l Electri c Coi l wa s contracte d t o manufactur e an d inst.-.il th

e ne wstato r winding s withou t impactin g th e outag e schedule . Competitiv e bid s wer e obtaine d fo r th e boile r work . Babcoc k & Wilco x wa s successful . Thi s scop e o f wor k wa s b yfar th

e mos t extensiv e o f th e project . B-.'-. ' wa s als o successfu l supplie r o f al l o f th e boile r materia l being installe d in thi s wor k package . Thi s offere d a grea t advantag e sinc e w e wer e abl e to negotiat e a singl e sourc e responsibilit yfrc m3&W for bot hmaterial s an d inst_L l laticn . 

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Thi s projec t involve d th e remova l o f asbesto s bearing insulatio n fro mth e entir e boiler , (ove r 15,00 0 sq . ft.) . Bot hth e remova l an

d th e replacemen t wer e performe d on fir mprice , competitiv e bi d contracts . R . E . Krami g Co . o f Cincinnati , Ohi o performe d th e removal . Powerhous e Equipmen t o f Akron , Ohi o performe d the replacement . Al l electrica l wor k wa s assemble d int o a packag e an d awarde d t o a loca l contractor , Watson-Flagg . Likewise , al l piping wor k (excep t fo r boile r related ) wa s assemble d i n a packag e an d awarde d b

ycompetitiv e bi d t o a loca l piping contractor , Mechanicals , Inc' . Th e condense r retubing an d installatio n o f I D fa n drive s (bothin seclude d area s o f th e plant ) wer e bi d separatel yan d awarde d t o a loca l contractor , Enerfab . Eac ho f the installatio n contractor s wer e require d t o provid e detaile d schedule s withi n severa l week s o f award . Thes e ba r chart s wer e require d t o includ e eac hstep o f th e installatio n proces s an d me n pe r shif t pe r da yfo r eacho f thes e steps . Thi s dat a became th e basi s fo r th

e projec t outag e schedule . Prio r t c award o f the installatio n contract s o n thi s project , ou r managemen t negotiate d an agreemen t wit hth e Nationa l Maintenanc e PolicyCommitte e fo r craf t labo r o f signator yunion s t o wor k a t 9 0 percen t o f ful l scal e wages . Thi s resulte d i n a considerabl e saving s i n installatio n cos t fo r thi s project . TH E OUTAG E TEA

M A s wit han

ymajo r project , a fiel d engineering staf f i s necessaryt o supervis e constructio n an

d administe r the contractors . Whe n our las t ne wuni t wa s completed , our norma l fiel d constructio n staf f wa s reassigned . Ane wtea m wit hspecia l characteristic s had t o b e assemble d fo r thi s project . Thes e specia l characteristic s fo r the Outag e Teamwere : 1 . Aclea r understanding o f existing plan t operation s an d goo d workin g relationship s wit hplan t personnel . 2 . Afamiliarizatio n wit hth e modification s an

d equipmen t t o be installed . Th e outag e lengt hdi d not ' allo wtim e fo r someon e t o b e trained . 3 . Th e tenacit ynecessaryt o effectivel ymanag e contracto r personnel . 4 . Awillingnes s t o devot e lon g hour s t o the project . Fulfilling thes e objective s require d a mi x o f engineering an d plan t personnel . Ou r Genera l Engineerin g an d Electri c Productio n Department s eac hcontribute d individual s t o th e Outag e Team . Temporaryreassignment s wer e made . Th e Outag e Coordinato r wa s brough t i n fro manothe r generating plant , thereb y allowing fo r hi s undivide d attentio n t o the project . Th e organizatio n i s show n i n Figur e 2 . Th e Outag e Coordinato r wa s directl yresponsibl e for the outag e work . Hi s tear , o f Fiel d Engineer s wer e th e singl e sourc e contact s fo r the contractors . I t wa s th e responsibilit yo f the Lif e Extensio n Projec t Leade r t o procur e equipmen t an d contractors . I t wa s th e Outag e Coordinator' s resDonsibilit vt o se e tha t th e contract s ar e carrie d out .P. 7

Th e Outag e Tea

mwa s locate d i n a roo mof f th

e Turbin e Roo

mfittingl ycalle d "Outag e Central" . A n outag e board 3 5 foo t lon g b y8 fee t hig

h(se e Figur e 3 ) displaye d al l schedule s fo r boile r an d balanc e o f plan t equipmen t installations . Asmalle r boar d on th e opposit e wal l displaye d turbin e work . Thes e board s wer e th e foca l poin t o f dail ycontracto r meetings . Eac hmorning a t 8:30A

M al l contracto r representative s groupe d t o discus s progres s fro mth e proceeding da

yan d activitie s t o tak e plac e tha t day . I f activitie s schedule d fo r th e previou s da

ywer e no t complete d a s scheduled , the ywer e move d bac k an d thei r impac t o n othe r operation s an d the overal l schedul e coul d b e assesse d immediately . Thes e meeting s coul d b e intimidating an d wer e an effectiv e tool . Th e discussio n o f dail yactivit yb yeac hcontracto r wa s ver yeffectiv e i n minimizin g lac k o f coordinatio n problems . The contractor s wer e als o responsibl e fo r reporting thei r manpowe r level s a t thes e meetings . TH E OUTAG E Th e outag e wa s schedule d fo r Octobe r 25 , 198 5 thru Januar y25 , 1986 . Th e firs t 1 5 day s o f the outag e wer e used exclusivel yfo r asbesto s insulatio n removal . Th e entir e boile r are a fro mas hhoppe r t o penthous e wa s enclose d wit hplasti c sheeting an d place d unde r a negativ e pressure . Th e insulatio n remova l contracto r worke d thre e 8-hou r shift s pe r da

yfo r thes e 1 5 day s an d complete d al l wor k a s scheduled . Eight ylarg e dumpster s o f materia l wa s removed . Durin g thi s work , w e maintaine d fiel d engineer s a t the sit e aroun d the cloc k t o ensur e th e wor k remaine d o n schedul e an d wa s complete d i n accordanc e wit happlicabl e safet yregulations . During thes e 1 5 days , the Boile r Roo mo f the uni t wa s closed of f t o al l othe r personnel . A s a result ; othe r contractors , sucha s th e boile r an

d piping contractors , coul d no t begi n wor k unti l Novembe r 11 , 1985 . Th e outag e wen t well . Job s initiall yconsidere d crucia l an d clos e t o impossible , suc ha s th e boile r ski n casing , wen t ver ywell . Al l contractors , wit hthe exceptio n o f the turbin e contractor , wer e originall yschedule d fo r on e o r tw

o 8-hour shifts . Th e turbin e wor k wa s don e o n tw o 10-hour shifts . I t wa s onl yduring th e las t wee k o f the outag e tha t limite d overtime became necessary . Thre e occurrence s too k plac e during th e outag e whic hhad grea t potentia l fo r upsetting th

e schedule . Eac hoccurrenc e wa s deal t wit haccordingl yan d adjustment s mad e t o compensate . As a result , th e schedule d completio n dat e remaine d unaffected . Thes e occurrence s ar e describe d below . 1 . As mentione d earlier , th e stato r rewin

d wa s foun

d t o b e in need o f rewinding . Coil s wer e manufactured , installe d an d tested withi n 8 week s o f award . 2 . Th e mai n stea

man d ho t rehea t line s wer e foun d t o be severel y exfoliated . Withi n 1 0 day s o f a decisio n t o aci d clean thi s piping , the cleaning systemconnection s wer e fabricate d an d installed , th

e cleaning completed , an d th e temporar

y connection s wer e removed . Tota l cos t o f thi s wor k wa s slightl yove r 5100,000 . Th e turbin e an d boile r contractor s wer e slightl ydelayed , however , a weeken d o f overtime brough t the mbac k o n schedule . 3 . Difficultie s in electrica l testin g an d delay s in releas e fo r testing . Adjustment s wer e mad e i n testin g responsibilities , wor k hour s an

d overtime t o compensate .



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The outag e wa s complete d on schedule . O n Januar

y25 , 1986 , a t 9:37A M the generato r rela

ywa s closed . On Januar y27 , 1986 , a col d spel l hi t the Cincinnat i are a an

d th e uni t wa s used t o produc e ove r 10 0 MW' s (7 5 percen t o f ful l load ) t o mee t th e systemdemands . Generato r vibratio n a t th e firs t critica l wa s unacceptable . Afte r severa l balanc e attempts , th e rewoun

d fiel d wa s removed an d balance d a t lowspeed o n site . Mi d plan e balanc e wa s require d t o reduc e vibration . Thi s fiel d removal , balance , an d replacemen t wor k took on e wee k afte r the uni t wa s finall yremove d fro mservice . COMPAN Y LABOR EFFORT CG& E labo r effort s wer e monitore d throughou t th e entir e projec t fro mstud y thru the ful l implementatio n o f lif e extensio n recommendations . Al l bu t on e o f the job s in thi s projec t wer e engineere d b yin-hous e engineerin g personnel . Al l fiel d engineering , drafting , an d electrica l testing wa s complete d b you r compan ypersonnel . Asummar yo f th

e hour s i s show

n i n Tabl e I I below :

Tabl e I I Summar yo f Compan

yLabo r WCB- 3 Lif e Extensio n Descriptio n Manhour s Engineering (stud

yonly ) 5,90 0 Engineering o f Modification s (incl . fiel d eng'rg. ) 13,80 0 Draftin g 8,20 0 Scheduling 1,10 0 Electrica l Testin g 8,40 0 Plan t Suppor t 1,60 0 Tota l 39,00 0 Figur e 4 compare s monthl ymanpowe r requirement s t o majo r event s i n th e schedule . CONCLUSION Ou r wor k i s complet e o n Uni t 3 . Al l modification s require d fo r lif e extensio n hav e bee n implemented . We can wal k awa yfro mth e uni t wit hreasonabl e assuranc e o f it s operating reliabl ythru th e extende d lif e period . The outag e wa s a grea t success . I t wa s complete d o n tim e an d withi n budget , an d a t a cos t o f les s than $100/kW . We'v e learned fro mour experienc e an d ar e implementing change s no wfo r our nex t outag e on WCB- 2 i n October , 1986 . Thi s wil l b e anothe r ful l implementatio n o f lif e extensio n recommendations . Th e PREMI S progra

mwil l b e used to schedul e no t onl ythe engineerin g an d procurement , bu t the actua l outag e wor k itself . Throughcarefu l planning fo r completio n o f eac hite mprio r t c contracto r bidding , w e hop e t o greatl yreduc e our electrica l testing an d contracto r overtime . Wor k scope s ar e being detaile d far in advanc e o f th e outag e t o minimiz e extr a work . W e ar e capitalizing or . our experienc e t o reduc e our engineerin g an d drafting efforts . Majo r scop e change s suc ha s th e rewin d o f th e generato r stato r an

d aci d cleaning o f th e mai n stea

man d ho t rehea t lin e ar e beingP. 9

planned . Ou r fiel d engineering personne l wil l b e bette r supporte d wit h assistanc e t o provid e bette r cos t contro l an d cos t reporting . ACKNOWLEDGEMENT S Presentatio n o f thi s pape r i s no t complet e withou t acknowledgemen t t o th e hundred s o f individual s wh o mad e thi s lif e extensio n projec t a success . Everyon e involved ; th e engineers , draftsmen , craf t labor , technicians , clerk s an d typist s playe d an importan t rol e i n the fina l outcome . Specia l recognitio n i s give n t o th e Outag e Team , whos e unselfis hdedicatio n t o th e projec t mad e the piece s al l come together .

REFERENCE S Pulskamp , B.E. , "Lif e Extensio n o f W . C . Beckor d Statio n - Unit s 1 , 2 & 3" , Electri c Powe r Researc hInstitut e Fossi l Plan t Lif e Extensio n Workshop , June , 198 4

4 4P.1 0



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GENERA L ELECTRI C 1

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BABCOC Kt i WILCO X| PROJEC TLEADE R

BALANC E O fPLAN T SPONSO R

. BECHTE L RECTRICA L EQUIPMEN T SPONSO R STRUCTURE S AN B ARCHITECTUR E SPONSO R

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