BATANGAS STATE UNIVERSITYCOLLEGE OF ENGINEERING, ARCHITECTURE AND FINE ARTSCHEMICAL AND FOOD ENGINEERING DEPARTMENTWRITTEN REPORTCOMPRESSORSSUBMITTED BY:LLANES, JENINA ROSA P. SUBMITTED TO:ENGR. KRISTINE MAY H. ESCALONA

INTRODUCTION The compressor industry has emerged from the decade of the 1980s right sized stream!ined and computerized" #anagement trends inc!ude a $roadening of responsi$i!ity for a!! departmentsto order to satisfy these ne% responsi$i!ities maintenance opeartions and engineering personne! need continuous re&ie% of compressor types c!assi'cations and app!ications" D()INITION *ND O+(R*TION )ans $!o%ers and compressors are machine designed to de!i&er gas at a pressure higher than that origina!!y e,isting" +ressure rise %or-ing pressurespeci'c speed and mechanica! design form the $asis of di.erentiation and c!assi'cation" The methods emp!oyed to achie&e compression are/ Trap consecuti&e 0uantities of gas in some type of enc!osure reduce the &o!ume this increasing the pressure then push the compressed gas out of the enc!osure Trap consecuti&e 0uantities of gas in some type of enc!osure carry it %ithout &o!me change to the discharge opening compressing the gas $y o&ercoming $ac- 1o% from the discharge system and pushing the compressed gas out of the enc!osure Compress the gas $y the mechanica! action of rotating impe!!ers or $!aded rotors that impart &e!ocity and pressure to the 1o%ing gas" *dditiona! &e!ocity energy in the gas is con&erted to pressure in an ad2acent stationary di.user or $!ade (ntrain the gas in a high &e!ocity 2et of another compati$!e gas and con&ert the high &e!ocity mi,ture into pressure &ia a di.user)*N 34O5(R CO#+R(66OR DI))(R(NTI*TION5hi!e di.erentiation of dynamic compressor types is possi$!e uti!izing dimensiona! ana!ysis is more common to !osse!y c!assify these machines $y the pressure rise they produce" )ans produce a pressure rise of 0"78 psi to 9"0 psi 3!o%ers produce a pressure rise of 1"0 psi to 8"0 psi Compressors produce a pressure rise greater than 8"0 psi COMPRESSORCompressors are used to hand!e !arge &o!umes of gas at pressure increases from 10"97 -+a :1"8!$g;in7< to se&era! hundred -+a :!$g;in7IT O) T=( I#+(44(R* centrifuga! compressor impe!!er can ha&e three types of $!ades at the e,itof the impe!!er" These are.!r,#r/-$ur0(/, #$+,#r/-$ur0(/,andr#/--#/(). F!r,#r/-$ur0(/ -#/() are not often used in a centrifuga! compressorFsimpe!!er $ecause of the &ery high?&e!ocity discharge at the compressor that %ou!dre0uire con&ersion of high &e!ocity to a pressure head in a di.use %hich isaccompanied $y high !osses" R#/- -#/() are used in impe!!ers of high pressureratiosincestress!e&e!sareminima!"B#$+,#r/-$ur0(/$!adesgi&ethehighesteHciency and the !argest operating margin of any of the &arious types of $!ades inan impe!!er" Pr!$()) $!"1r())!r)ha&e impe!!ers %ith &ery !o% pressure ratio impe!!ers andthus !arge surge?to?cho-e margins" The common method of c!assifying process?typecentrifuga! compressors is $ased on the num$er of impe!!ers and the casing design"S($t&!'#-&2(/$#)&'*t31()ha&eimpe!!ers that areusua!!ymountedonthee,tended motor shaft and simi!ar sections are $o!ted together to o$tain the desirednum$erofstages"C#)&'* "#t(r-iseitherstee! orcastiron" Thesemachinesre0uireminimumsuper&isionandmaintenanceandare0uiteeconomicintheiroperating range" The %!r&2!'t#--3 )1-&t-t31(ha&e casings sp!it horizonta!!y at the midsection andthe top" The $ottom ha!&es are $o!ted and do%e!ed togetherB#rr(- $#)&'*) are used for high pressures in %hich the horizonta!!y sp!it 2oint isinade0uate" This type of compressor consists of a $arre! into %hich a compressor$und!e of mu!tip!e stages is inserted" COMPRESSOR CONFIGURATIONToproper!y designacentrifuga! compressoronemust-no% the operatingconditions? the type of gas its pressure temperature and mo!ecu!ar %eight" Onemust a!so -no% the corrosi&e properties of gas so that proper meta!!urgica! se!ectioncan $e made" Eas 1uctuations due to process insta$i!ities must $e pinpointed sothat the compressor can operate %ithout surging"6ome factors to $e considered %hen se!ecting a con'guration to meet p!ant needsare/1" Intercoo!ing $et%een stages can considera$!y reduce the po%erconsumed"7" 3ac-?to?$ac-impe!!ersa!!o%for a$a!ancedrotor thrust andminimizeo&er!oading the thrust $earings"9" Co!d in!et or hot discharge at the midd!e case reduces oi!?sea! and!u$rication pro$!ems"D" 6ing!e?in!et or sing!e discharge reduces e,terna! piping pro$!ems8" 3a!ancep!anes that areeasi!yaccessi$!einthe'e!dcanapprecia$!yreduce 'e!d?$a!ancing times"@" 3a!ance piston %ith no e,terna!!ea-age %i!!great!y reduce %ear on thethrust $earings"A" =otandco!dsectionsof thecasethataread2acenttoeachother%i!!reduce therma! gradients and thus reduce case distortion"8" =orizonta!!y sp!it casings are easier to open for inspection than &ertica!!ysp!it ones reducing maintenance time"9" O&erhung rotors present an easier a!ignment pro$!em $ecause shaft? enda!ignment is necessary on!y at the coup!ing $et%een the compressor andthe dri&er" 10"6ma!!er high?pressurecompressors that dothesame2o$%i!! reducefoundation pro$!ems $ut %i!! ha&e great!y reduced operationa! range" IMPELLER FABRICATIONCentrifuga! compressor impe!!ers are either shrouded or unshrouded"O1(',)%r!u/(/&"1(--(r)aremain!yusedinsing!e?stageapp!icationsaremade$yin&estment?casting techni0ues or $y three?dimensiona! mi!!ing" R&0(t(/ &"1(--(r)%ere used in the 19@0s I they are &ery rare!y used no%" #ateria!s for fa$ricating impe!!er are usua!!y !o%?a!!oy stee!s" M!'(- K-455 isemp!oyedinha!ogengasatmospheresando,ygencompressors$ecauseof itsresistance to spar-ing" T&t#'&u" &"1(--(r) ha&e $een app!ied to ch!orine ser&ice"A-u"&'u"-#--!3&"1(--(r)ha&e$eenusedingreat num$ers especia!!y!o%ertemperatures" A6IAL FLOW COMPRESSORSA7- 8!, $!"1r())!r)are used main!y as compressors for gas tur$ines"They are a!so used in the stee! industry as $!ast furnace $!o%ers and in the chemica!industry for !arge nitric acid p!ants" They are main!y used for app!ications %here thehead re0uired is !o% and the 1o% !arge)igure10?AAsho%satypica! a,ia!?1o%compressor" Therotatinge!ementconsists of a sing!e drum to %hich are attached se&era! ro%s of decreasing?height$!ades ha&ing airfoi! cross sections" 3et%een each rotating $!ade ro% is a stationary$!ade ro%" *!! $!ade ang!es and areas are designed precise!y for a gi&enperformance and high eHciency" The use of mu!tip!e stages permits o&era!! pressureincrases up to 90/1" The eHciency in an a,ia! 1o% compressor is higher than thecentrifuga! compressor" The a,ia! 1o% compressors used in gas tur$ines &ary depending on the typeof tur$ines" The industria!?type gas tur$ine has an a,ia! 1o% compressor of a ruggedconstruction" Theseunits ha&e$!ades that ha&e!o%aspect ratio:RC$!adeheight;$!ade chord< %ith minimum stream!ine cur&ation and the shafts are supporton s!ee&e?type $earings" The &'/u)tr- *#) tur&'( $!"1r())!r has a!so a !o%erpressureratioper stage:stageCrotor Jstationary$!ade< gi&inga!o%$!ade!oading" This a!so gi&es a !arger operating range than its counterpart the aero a,ia!gas tur$ine compressor $ut considera$!y !ess than the centrifuga! compressor"Thea,ia! 1o%compressorsin#(r! *#) tur&'()are hea&i!y !oaded"Theaspect ratio of the $!ades especia!!y the 'rst fe% stages can $e as high as D"0 andthe e.ect of stream!ine cur&ature is su$stantia!" The stream!ine con'guration is afunction of the annu!ar passage area the cam$er and thic-ness distri$ution of the$!ade and the 1o% ang!es at the in!et and out!et of the $!ades" The shafts on theseunits are supported on antifriction $earings :ro!!er or $a!! $earings