洛氏硬度计英文说明书

第第4页共4页Abriefintroductionto150ARockwellhardnesstesterRockwellhardnesstesterisauniversalizedapparatusforRockwellhardnessdetermination.ItcanbeusedinthetestofRockwellhardnessofvariousmaterials.Theapplyingspeedoftestpressurecanbeadjustedbyabufferingdeviceandthechangeofpressureisobtainedbyturningofapressureselectinghandwheel.Operationofthetesterisquiteeasy,whiletheperformanceisstable,andthusthetestercanbeusedinawiderange.WorkingprincipleoftheRockwellhardnesstesterThetestprocedureemploysaconicaldiameterindenterorballindenterofacertaindiametertopressintospecimen,aninitialtestpressurepoandamaintestpressureP1willbeappliedontheindenterinsequence,andthetotalpressure（P0+P1）willbekeptforacertainperiod,thenthemainpressureistoberemoved,onlytheinitialpressurewillbeleft.Adifferencebetweentheindentdepthh1bythistimeandtheindentdepthh0undertheactionofinitialpressureisrecordedasapermanentincrementofindentdepth.Every0.002mmofthisincrementrepresentsaunitofRockwellhardness.Thisisaquicktestandonlytrivialindentwillbecaused.Soitiswidelyusedtodeterminethehardnessofspecimen.CalculationFormulaofRockwellHardness.HRA(C)=100-e/0.002HRB=130-e/0.002TechnicalspecificationsofthehardnesstesterInitialpressure:98.07N.Tolerance:±2%Totalpressure:588.4N,980.7,1470N.Tolerance:±1%SpecificationofindenterConicaldiamondRockwellindenter,diameter1.5875mmballindenterMax.Heightofspecimen:170mmDistancebetweencenterofindenterandthecolumn:165mmOverallsizeofthetester(L*W*H):510*212*700Totalweightofthetester:85kg(approx.)Repeatability&ToleranceofRockwellHardnessDisplayValue.Scale HardnessofStandardBlocks20HRA-≤75HRA20HRB-≤45HRB>80HRB-≤100HRB

DisplayTolerance±2HRA±1.5HRA±4HRB±3HRB±2HRB

AllowableDisplayRepeatability≤0.02(100-H)or0.8Rockwellunitb)≤0.04(130-H)orRockwellunitb)CC20HRC-≤70HRC±1.5HRC≤0.02(100-H)or0.8Rockwellunitb)WhereHisthemeanhardnessvalue.Takethelargeoneofthesetwovaluesasbasis.InstallationofthetesterWorkingconditionsofthetesterUnderambienttemperature.i.e.between10-30oCTherelativehumidityintestroomshallnotbeover65%InanenvironmentfreefromvibrationNocorrosivemediuminsurroundingTesterunpackingRemovenails,openthepackingboxcoverandtakeoutallcushionmaterials.RemovetheaccessoryboxLoosenthefournutsonthebottomofthepackingbox.ThenlifttheboxupwardandremoveitLiftthebottomplate,unscrewthetwoM10boltsunderthebottomplatewithaspanner,toseparatethehardnesstesterfrombottomplate,allstepsshallbedoneinasafemanner.Afterunpackingthetestershallbeplacedonastablebenchwithlevelnessdeviationlessthan1mm/m.Aholeshallbedrilledatanappropriatelocationonthebenchtoenabletheliftingscrewtooperateproperly.Afterthehardnesstesterisproperlyplaced,removethetopcover.Unitethefasteningwhitegauzetapeontheextensionrod,andthenpromptlyplacethetopcovertopreventdustfromcomingintothetester.Opentherearcoverandremovethewhitegauzetapeonmoveableparts.Wipeofftheanti-rustoilontheliftingscrewandapplysomethinlubricatingoilinstead.InstallationofweightsScaleTestPressureGraduationN.AppliedWeightsHRA588Hanger+WAHRB980Hanger+WA+WBHRC1470Hanger+WA+WB+WCProperuseofthetesterPreparationspriortotheuseSurfaceofthespecimentobetestedmustbesmoothandclean,freefromdirt,scalingindentationorsignificantmarksresultedfrommachining.Min.thicknessofthespecimenshallbe10timeslargerthanthedepthofindenture.Noobviousdeformationshallbeseenonbackofthespecimenafterhardnesstest.Therelationshipbetweenmin.thicknessofthespecimenanditshardnessareshowninthefollowingtable.Thespecimentobetestedshallbeplacedinstablestateontopoftheteststock.Itshallbefixedduringthetestprocess.Ensurethatthetestpressureisperpendicularlyexertedonthe。Incaseofacylindricalshapespecimentobetested,theVtypeteststockshallbeusedandoffsetneedstobemadetothevalues.Offsetforcylindricalshapespecimenshallbeapositionvalue.OffsetsforRockwellhardnesstestwhendiameterofthespecimenislessthan38mm.HardnesstesteroperationprocedureChooseascaleaccordingtotable2basedontheroughhardnessofthematerialtobetested.Turnthepressureselectinghandwheelclockwisetosetthetotalpressure.Whenusethediamondindenter,presstheheadofdiamondwithmiddlefingerandgentlypushitintotheholeonindenterrodtillitrestsneatlyonthesupportingsurface,thenslightlytightentheindenterlockingscrewandplacethespecimenonteststock.Rotatetheturnwheelclockwisetolettheliftingscrewmoveupward,ensuringthatthespecimentobetestedslowlycontactwiththeindenterwithnoimpacttilltheshortpointeronthecentigradepanelturnfromblackpointtoberedone.Andbythistimethelongpointershallhavepassedthreeturnsandpointtoposition"C"(orposition"B"incaseofHRBdetermination),thisindicatesthattheinitialtestpressureof98.07Nisachieved.Thedeviationoflongpointershallnotexceed5grades.Otherwisethepointershallnotbeallowedtoturnback;insteadthetestspotshallbechangedtorestarttheoperation.Rotatethegraduationdialtosetthepointeronposition"C".Pushthepressureapplyinghandleslowlybackwardandensurethatthemainpressureshallbewhollyexertedin4-6seconds.Thetotalpressureholdingtimeperiodis5seconds,afterthenpullthepressureapplyinghandlesteadilyforwardin2-3secondstoremovethemainpressureandonlytheinitialpressureisleft.Thevaluepointedbythelongpointeroncentigradepanelatthistimeshallbetaken as the determined hardness value of the specimen (in case of determination,valueshallbereadfromtheinnercircle)Rotatetheliftingwheelcounter-clockwisetolowertheteststock.RepeataboveprocedureatvariousspotsScaleIndenterScaleIndenterInitialPressure(N)TotalPressure(N)ApplicationsADiamondindenter,Conicalangle120o588hard alloy, carbide, surfacequenchedsteel,carburizingsteelDSpherical radius atthinsteel sheet,vertex0.2mm980surfaceC1471quenchedsteelquenchedsteel,temperedsteel,hardcastironcast iron, aluminum, magnesiumF588alloy, bearing alloy annealedBBallindenterdiameter1.5875mm(1/16in)98.07copperalloy,mildsteelsheetmildsteel,aluminumalloy,copper980alloy,malleablecastiron,G1471annealedsteelphosphorusiron,berylliumbronze,malleablecastironH588980aluminum,zinc,lead,etc.EBallindenterdiameter3.175mm(1/8in)F1471bearingalloy,tin,hardplasticsandothersoftmaterialsInexecutionofthehardnesstesteroperationproce