Alfa Laval ALS - Page 67

6Technicaldata
Alldimenstionsinmmunlessotherwisestated.
Pr Pr
Pr
ocedur ocedur
ocedur
e: e:
e:
1.Alignmentoftheshaftiscarriedoutinstepsfromthebearingframe/gearmotoranddowntotheshaftend.
2.Iftheshafthasbeenexposedtounevenheataround“A”(duetoweldingofshaftconnectionorweldingofpropeller
ontoshaft)apossiblebendcanbeintroducedaround“A”.
3.Thedialindicatorislocatedabout500-2000mmbelow“A”(butabovethenextbend“B”)andtheshaftisrotateduntil
theshaftispointingtotheleftasshownonthepicture.
4.Theweldingtorchisusedontheoppositesiteofthebend(therightsideoftheshaftinthisexample)about25-50mm
furtherupordownfromtheweldingarea“A”.Theweldingtorchispositionedveryneartheshaftsurfacewithoutmovingit
andthesurfaceoftheshaftisrapidlyheatedup(1-10secondsdependingonshaftbend)untilaØ2-10mmredspotis
observed.Observingthedialindicatortheshaftwill,duringtheheatingprocess,bendevenmoretothewrongdirectionbut
duringcoolingitbendsbacktoa“more”alignposition.
5.TheshaftiscooleddownwithcompressedairuntilthetemperatureofthepartoftheshaftaroundAisthesameastherest
oftheshaftandthesurroundingtemperature(2-10minutesdependingonamountofheatintroduced).
6.Step3),4)and5)arerepeateduntilthealignmentisaccordingthespecified“U”(whichisafunctionofspeedand
Agitatortype).
7.Thenextposition“B”wheretheshafthasbeenexposedtounevenheatislocated(duetoweldingofshaftconnection
orweldingofpropellerontoshaft).
8.Thedialindicatorislocated500-2000mmbelow“B”(butabovethenextbend)orattheshaftendiftheshaftdoesnothave
anyotherbendsandtheshaftisrotateduntiltheshaftispointingtotherightasshownonthepicture.
9.Theweldingtorchisusedontheoppositesiteofthebend(theleftsideoftheshaftinthisexample)about25-50mmfurther
upordownfromtheweldingarea.Theweldingtorchispositionedverynearshaftsurfacewithoutmovingitandthesurface
oftheshaftisrapidlyheatedup(1-10secondsdependingonshaftbend)untilaØ2-10mmredspotisobserved.
10.TheshaftiscooleddownwithcompressedairuntilthetemperatureofthepartoftheshaftaroundAisthesameastherest
oftheshaftandthesurroundingtemperature(2-10minutesdependingonamountofheatintroduced).
11.Step8),9)and10)arerepeateduntilthealignmentisaccordingthespecified“U”(whichisafunctionofspeedand
Agitatortype).
12.Thespotareaswheretheshafthasbeenheatedandalignedusingtheweldingtorchmustbecleaningusingchemical
picklingandormechanicalabrasivepolishing.
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