Major Factors Affecting the Pump Performance

MAJOR FACTORS AFFECTING AFFECTING THE PUMP PERFORMANCE Pump or Pumping system is a major eupment in any pro!ess or po"er p#ants$ So t%e euipment s%ou#& opearate proper#y to gi'e (est output in terms o) per)orman!e$ Ho"e'er* t%ere t%ere are many )a!tors "%i!% in)#uen!e t%e pump per)orman!e$ Out o)  t%ose* t%e main +major, )a!tors "%i!% a))e!t t%e per)orman!e o) pump areImpe##er &esign Improper priming Insu))i!ient NPSH Re&u!e& !apa!ity .rong &ire!tion o) rotation C#ogging o) su!tion pipe#ine an& impe##er  Improper s%a)t a#ignment Pa!/ing trou(#es Noisy operation T%is arti!#e "i## e0p#ain t%ese points in s%ort$ IMPELLER DESIGN: 1a!/"ar& !ur'e& (#a&es* 234567 For"ar& !ur'e& (#a&es* 238567 Ra&ia# (#a&es * 239567 T%e )o##o"ing ta(#e pro'i&es a gui&e#ine )or pump per)orman!e "it% 'arious (#a&es$ • • • • • • • • •

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IMPR$PER PRIMING:  A## t%e air in t%e pipe #ine #ine s%ou#& (e e0pe##e& !omp#ete#y T%e pump s%ou#& (e prime& !omp#ete#y (e)ore starting Su!tion pipe s%ou#& (e :m (e#o" t%e #o"est "ater #e'e# It s%ou#& (e !omp#ete#y air tig%t E!!entri! re&u!ers s%ou#& (e use& i) ne!essary to a'oi& air po!/ets in pipe #ine INS%!!I&IEN' NPS(: NPSH9 +Patm;P',B +Patm;P',B g D %s D %)s NPSH &epen&s on t%e temperature o) t%e operating #iui& ariation a riation in "ater #e'e# is !onsi&era(#e D o"est #e'e# s%ou#& (e ta/en in to a!!ount )or NPSH &etermination Fri!tiona# #osses s%ou#& (e /ept minimum (y se#e!ting suita(#e &iameter$ &iameter$ It is !ommon#y a!!epte& t%e stati! %ea& in t%e pump "i## (e maintaine& as <$m )or "ater "it% a temperature o) :6; 367! NPSH a'aia(#e 8 NPSH reuire& RED%&ED &)P) &)P)&I'*: &I'*: One o) t%e main reason )or t%e re&u!e& !apa!ity is in!rease& %ea& Tota# %ea& 8 &esigne& %ea& Pump or t%e impe##er s%ou#& (e !%ange& to o(tain t%e rate& !apa!ity +R$NG DIRE&'I$N $! R$')'I$N: R$')'I$N: T%is !ause t%e rate& !apa!ity an& %ea& "i## not (e o(taine& Pump )ai#s o)ten to operate Reme&y arro" !ast is in&i!ate& in pump !asing o o !are s%ou#& (e ta/en "%i#e mounting t%e impe##er  &L$GGING $! S%&'I$N PIPELINE )ND IMPELLER: Su!tion pipe is !#ogge& (y some (ri!/s* "oo&s o)ten • • • •

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Strainer is !#ogge& (y paper* #ea'es To re!ti)y t%is pipe#ine s%ou#& (e inspe!te& perio&i!a##y IMPR$PER S()!' )LIGNMEN': It is &ue to misa#ignment o) motor an& pump s%a)t It resu#ts in t%e 'i(ration an& noisy operation To a'oi& t%is t"o s%a)ts s%ou#& (e a#igne& proper#y N$IS* $PER)'I$N:  Air #ea/age in t%e pump S%a)t misa#ignment resu#ting in t%e 'i(ration Ca'itations T%ey !an (e re&u!e& (y proper &ynami! (a#an!e o) t%e s%a)t an& impe##er  T%e !a'itations is re&u!e& (y proper#y &esigning t%e pump "it% suita(#e NPSH • •

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Consi&era(#e points "%i#e insta##ing !entri)uga# pumps at site to re&u!e 'i(ration "ant3#earn Septem(er 3* 36:<

No Comment 

For proper )un!tioning o) t%e !entri)uga# pumps in any p#ant t%e )o##o"ing points nee& to (e ta/en !are "%i#e insta##ing$ &eck-./ e s-e be1"re -.salla-".: Ma/e sure t%e )oun&ation !on!rete is o) su))i!ient strengt%$ On#y p#a!e t%e pump set on a )oun&ation "%ose !on!rete %as set )irm#y$ On#y p#a!e t%e pump set on a %orionta# an& #e'e# sur)a!e$ Re)er to t%e "eig%ts gi'en in t%e Pump genera# arrangement +GA, &ra"ing$  A## stru!tura# "or/ reuire& must %a'e (een prepare& in a!!or&an!e "it% t%e &imensions state& in t%e out#ine &ra"ingBgenera# arrangement &ra"ing$ I3r"3er -.salla-". -. 3"e.-all4 e53l"s-ve a"s3eres: Comp#y "it% t%e app#i!a(#e #o!a# e0p#osion prote!tion regu#ations$ O(ser'e t%e in)ormation in t%e &ata s%eet an& on t%e name p#ates o) pump an& motor$ I.sall-./ e 3u3 assebl4:  A#"ays insta## t%e pump set in %orionta# position to ensure proper se#);'enting o) t%e pump$ Re)er Fig$ :• • • • •

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!-/6 7: !-/ure s"w-./ e 1"u.da-". "1 3u3 Position t%e pump on t%e )oun&ation an& use a spirit #e'e# to a#ign s%a)t an& & is!%arge no#e$ Permissi(#e &e'iation- 6$3 mmBm$ I) reuire&* use s%ims +3, to a&just t%e %eig%t$ Fit s%ims (et"een t%e (asep#ateB)oun&ation )rame an& t%e )oun&ation itse#) a#"ays insert t%em to t%e #e)t an& rig%t o) t%e )oun&ation (o#ts an& in !#ose pro0imity to t%ese ( o#ts$ For a (o#t;to;(o#t !#earan!e 8 ?66 mm* insert a&&itiona# s%ims %a#)"ay (et"een t%e a&joining %o#es$ A## s%ims must #ie per)e!t#y )#us%$ Insert t%e )oun&ation (o#ts +=, into t%e %o#es pro'i&e&$ Use !on!rete to set t%e )oun&ation (o#ts +=, into t%e )oun&ation$ .ait unti# t%e !on!rete %as set )irm#y an& t%en a#ign t%e (asep#ate$ Tig%ten t%e )oun&ation (o#ts +=, e'en#y an& )irm#y$ Grout t%e (asep#ate using #o";s%rin/age !on!rete "it% a stan&ar& parti!#e sie an& a "aterB!on!rete ratio o)  6$>$ Pro&u!e )#o";a(i#ity "it% t%e %e#p o) a so#'ent$ For #o";noise operation t%e pump set !an (e mounte& on 'i(ration &ers upon !on)irmation (y t%e manu)a!turer$ In t%is !ase* on#y )asten t%e )#e0i(#e e#ements at t%e (asep#ate a)ter t%e piping %as (een !onne!te&$ E0pansion joints !an (e )itte& (et"een pump an& su!tionB&is!%arge #ine$ O(ser'e t%e permissi(#e )or!es an& moments at t%e pump no#es$

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Ta/e appropriate measures to !ompensate t%erma# e0pansion o) t%e piping$ T%e su!tion #i)t #ineBsu!tion %ea& #ine %as (een #ai& "it% a risingB&o"n"ar& s#ope to"ar&s t%e pump$ T%e nomina# &iameters o) t%e pipe#ines are at #east eua# to t%e nomina# &iameters o) t%e pump no#es$ To pre'ent e0!essi'e pressure #osses* a&apters to #arger &iameters %a'e a &i))user ang#e o) appro0imate#y ?7$ T%oroug%#y !#ean* )#us% an& (#o" t%roug% a## 'esse#s* pipe#ines an& !onne!tions +espe!ia##y o) ne" insta##ations,$ 1e)ore insta##ing t%e pump in t%e piping* remo'e t%e )#ange !o'ers on t%e su!tion an& &is!%arge no#es o) t%e pump$ Use a )i#ter "it% #ai&;in "ire mes% +mes% "i&t% 6$> mm* "ire &iameter 6$3> mm, o) !orrosion;resistant materia#$ Use a )i#ter t%ree times t%e &iameter o) t%e piping$ Coni!a# )i#ters %a'e pro'e& suita(#e$ T%e 'o#ute !asing an& !asingB&is!%arge !o'er ta/e on t%e same temperature as t%e )#ui& %an&#e&$ Ma/e sure t%e spa!e (et"een t%e !asing !o'erB&is!%arge !o'er an& t%e (earing !o'er is su))i!ient#y 'ente&$ Ne'er !#ose or !o'er t%e per)oration o) t%e (earing (ra!/et guar&s$ Ne'er insu#ate t%e !asing !o'er an& t%e (earing (ra!/et$ Ma/e sure t%at t%e !oup#ing is !orre!t#y a#igne& at a## times$  A#"ays !%e!/ t%e !oup#ing a)ter t%e pump %as (een insta##e& an& !onne!te& to t%e piping$  A#so !%e!/ t%e !oup#ing o) pump sets supp#ie& "it% pump an& motor mounte& on t%e same (asep#ate$ Re)er Fig$ 3$

!-/6 2: &eck-./ e s3acer843e c"u3l-./ w- a d-al /au/e •

Mar/ t%e insta##ation position o) t%e !oup#ing (y &otting mar/s +(a#an!ing !on&ition,$

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Remo'e t%e !oup#ing spa!er$

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.%i#e t%e pumps !oup#ing is &isengage&* a#so !%e!/ t%e &ire!tion o) rotation$

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C%e!/ t%e a#ignment o) t%e !oup#ing %a#'es "it% a &ia# gauge +see Fig$ 3,$ A&missi(#e run;out o) !oup#ing )a!e +a0ia#, ma0imum 6$: mm$ A&missi(#e ra&ia# &e'iation* measure& o'er t%e !omp#ete !ir!um)eren!e* ma0imum 6$3 mm$  A)ter %a'ing insta##e& t%e pump set an& !onne!te& t%e piping* !%e!/ t%e !oup#ing a#ignment an&* i) reuire&* re;a#ign t%e pump set +"it% t%e motor,$ Any &i))eren!es in s%a)t !entre %eig%t (et"een t%e pump an& t%e motor are !ompensate& (y means o) s%ims$

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C%e!/ t%e !oup#ing a#ignment$

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Uns!re" t%e %e0agon %ea& (o#ts at t%e motor$

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Insert s%ims un&erneat% t%e motor )eet unti# t%e &i))eren!e in s%a)t !entre %eig%t %as (een !ompensate&$ Re)er Fig$ K$

!-/6 : Pu3 Se w- S- •

Re;tig%ten t%e %e0agon %ea& (o#ts$

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C%e!/ t%at t%e !oup#ing an& s%a)t !an easi#y (e rotate& (y %an&$

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 A#"ays operate t%e pump set "it% a !oup#ing guar&$ I) t%e !ustomer spe!i)i!a##y reuests not to in!#u&e a !oup#ing guar& in en&ors &e#i'ery* t%en t%e operator must supp#y oneL O(ser'e a## re#e'ant regu#ations )or se#e!ting a !oup#ing guar&$

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Reinsta## t%e !oup#ing guar& an& step guar&* i) any$

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C%e!/ t%e &istan!e (et"een !oup#ing an& !oup#ing guar&$ T%e !oup#ing guar& must not tou!% t%e !oup#ing$

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C%e!/ t%e a'ai#a(#e mains 'o#tage against t%e &ata on t%e motor name p#ate$

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Se#e!t an appropriate start;up met%o&$

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C%ange t%e motors &ire!tion o) rotation to mat!% t%at o) t%e pump$

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O(ser'e t%e manu)a!turers pro&u!t #iterature supp#ie& "it% t%e motor$ Ne'er !%e!/ t%e &ire!tion o) rotation (y starting up t%e un)i##e& pump set$ Separate t%e pump )rom t%e motor to !%e!/ t%e &ire!tion o) rotation$

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Ne'er insert your %an&s or any ot%er o(je!ts into t%e pump$ C%e!/ t%at t%e insi&e o) t%e pump is )ree )rom any )oreign o(je!ts$ T%e !orre!t &ire!tion o) rotation o) motor an& pump is in !#o!/;"ise &ire!tion +seen )rom t%e motor en&,$ I) t%e &ire!tion o) rotation is in!orre!t* !%e!/ t%e !onne!tion o) t%e motor an& t%e s"it!%gear* i) any$

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