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1、数控火焰切割应注意的问题()CNCflamecuttingshouldpayattentiontotheproblem(2011-04-2118:19:32)Tags:.Flamecuttingaccuracyreferstotheerrorrelationshipiscuttingmachinefinishedworkpiecegeometryanddrawingsizecontrast,cuttingqualityreferstothesurfaceoftheworkpiececuttingsectionofroughmeltingcoll
2、apsedegree,incisionontheedgeoftheedge,whethertheedgeincisionslagandkerfwidthuniformity・Threebasicfactorsthataffectthequalityofflamecutting(gas,cuttingspeed,cuttingnozzleheight)1.Gas(1)oxygenandoxygenarenecessaryforcombustionofcombustiblegases・Inordertoprovidetherequiredenerg
3、yfortheignitiontemperature,andtheoxygenisnecessarytoburnafterbeingpreheatedtothepointofignition.Theoxygenusedforcuttingsteelmusthavehigherpurity,andgenerallyrequiremorethan99.5%.Someadvancedcountriesrequiremorethan99.7%purityofoxygen.Thestabilityofthegaspressureisalsocrucial
4、tothecuttingqualityoftheworkpiece・Ingeneral,thefollowingparameterscanbeoperated:Cuttingoxygenpressure7~8kg/cm2;Acetylenepressure>0.3kg/cm2;Preheatoxygenpressure3^4kg/cm2・(1)thereareacetylene,gas,naturalgas,propaneandsooninthef1amecuttingoff1ammab1egas・Someforeignmanufacturer
5、sstilluseMAPP,thatis,methane+ethane+propane・Generallyspeaking,highspeed,highcalorificvaluegascombustionisusedforsheetcutting;combustionvalueislow,slowcombustionofcombustiblegasismoresuitableforcutting,especiallywithathicknessofmorethan200mmsteelplate,suchastheuseofmediaornat
6、uralgascutting,andcuttingqualitywillgetto,justcuttingspeedslightlylower・(2)thef1ameadjustmentcanbeobtainedbythreekindsofflamecuttingbyadjustingtheratioofoxygenandacetylene:neutralflame(i.e.normalflame),oxidizingflame,reducingflame.Thenormalflameischaracterizedbytheabsenceoff
7、reeoxygenandactivatedcarboninitsreductionzone・Therearethreedistinctregions,withadistinctoutline(nearcylindrical)・Thecoreoftheflameisacetyleneandoxygen,anditsendsareuniformlycircularandbright.Theshellconsistsofreddishcarbonaceousdots・Thetemperatureoftheflamecoreis1000degreesc
8、entigrade・Thereductionzoneisoutsidetheflamecore,andthedistinctdifferencefro