外文翻译--小动力掘进机在不同岩石面挖掘隧道的实验结果.doc
翻译部分英文原文AbstractInthispaper,theexperimentalresultsofa45-kWand15-troadheaderexcavatingagallerywithtwodifferenttypesofrockatthefaceusingtwodifferentcuttingheadsareshown.Itisprovedthattheroadheaderworksproperlywithbothcuttingheads.Incomparisonwithotherresultsintheliterature,theprincipalparameters,i.e.specificenergy,cuttingrateandtoolwear,areatalevelthatcanbeconsideredsatisfactorytakingintoaccountthelowpoweroftheroadheader.Ontheotherhand,theinfluenceofthenumberofpicks,whichisthemaindifferencebetweenthetwocuttingheads,ontheoperationalparametersisshown.2003ElsevierScienceLtd.Allrightsreserved.Keywords:Roadheaders;Cuttingheaddesign;Specificcuttingenergy;Cuttingrate;Toolwear1.Introduction:experienceinusingofroadheadersinamineThecoalbasinintheNWofSpain(Arecesetal.,1994)formsasynclineinwhichthecoalseamsaremoderatelyinclined(30358)attheNWfoldaxisandalmostvertical(70908)attheSEfoldaxis.CarboniferousmaterialoccursunderaflatPermianoverburden,150mthick.Theuseofroadheadersinthisminewasaconsequenceofmechanisationofthework.Coalminingbythelong-wallmethodwithpoweredroofsupportsmakesrapidadvanceoftheaccessroadsnecessary.Ontheotherhand,thetwoalternativesforminingverythickcoalseams,i.e.room-and-pillarinflatseamsandsublevelcavinginverticalseams,alsomakestheuseofroadheaderdrivinggalleriesinthecoalseamsnecessarySeveraltypesofroadheadersareusedinthemineforthesedifferentworks:a.Oneroadheader(Fig.1)of60tinweight,witha250-kWrippingcuttinghead,especiallydesignedforthistypeofmineinthecontextofresearchproject(Anon.,1991;Toranoetal.,1992;Torano,1994)withtheobjectiveofdrivinggalleriesof10-mcross-2sectionsincoalseamsof1.01.5minthickness(withapprox.50%ofthesectioninhardrockofuniaxialcompressivestrengthuptosc120MPa);b.Tworoadheaders(Fig.2)of24tinweight,witha110-kWrippingcuttingheadmainlyusedindrivinggallerieswithmediumhardrock(c60MPa)orincroom-and-pillarmining;c.Tworoadheaders(Fig.3)of12.5tinweightwithamillingcuttingheadof45kW,onlyusedinadvancingofgalleriesincoal(softrock);theconveyortypemeanstheroadheaderhasa2.8-mwidthandbecauseofthisitcanonlybeusedforadvancinggalleriesincoalseamsof3.0minthickness(mainlyintheminingmethodtermedsublevelcaving);andd.Oneroadheader(Fig.4)of15.5tinweightwitha45-kWmilling-typecuttinghead,developedwiththisnarrowdesignespeciallyforthismine(Toranoetal.,1997)foritsapplicationindrivinggalleriesin2.0-m-thickcoalseams(minimum1.70m)inwhichpreviousroadheaderscouldnotbeused.Thestudydescribedherewascarriedoutinthecontextofthisproject.Duringtheadvanceofgalleriesin2.0-m-thickcoalseams,itwassometimesnecessarytoexcavatetherockoftheseamwalls,thestrengthofwhichwasalmostoverthelimitofthecuttingcapacityoftheroadheader.Itwasdecidedtoinvestigateif,undertheseconditions,theoperationorcuttingparameterswereacceptableusingtwodifferentcuttingheadsinthetest.2.Testdescription2.1.TestobjectivesTheaimwastodeterminethepossibilityofdrivingthesegalleriesbymeansofa45-kWroadheader,comparingtwodifferentcuttingheadsexcavatingthesametypeofrockinsimilaroperatingcycles.Themaindifferencebetweenthetwocuttingheadswasthenumberofpicks:thefirstcuttingheadhad36picks,whilethenewonehadonly24(Fig.5).Becauseofthelowernumberofcuttingtoolsincontactwiththerock,thetorquetransmittedbythemotorwastransformedtoalargertangentialforceinthepick,whichallowshigher-strengthrocktobecut.Stressconcentrationisthemajorfactorinrockfragmentation.Theparameterstomeasure(accordingtoclassicstudiesonthistheme;FowellandMcFeat-Smith,1976;Gehring,1989)arethecuttingrate(volumeofrockexcavatedpertimeunitinm3/s),specificenergy(ener-3gynecessarytoexcavateaunitofvolumeinMJ/m3)3andthetoolwearorspecificpickconsumption(picksorpickmasslostexcavatingaunitofvolumeofrockinpicks/m3org/m3).Allparametersweremeasured33whentheroadheaderwasexcavatingcoalandrock,aswellaswhenitwasperformingotherpartsofthecycle.