ileontheleftthecoalwascstrong(σc=–MPa)withoutrockbetweenthem.CTheleftwallwasofsiltstone(sometimessandstone)withacompressivestrengthofssMPa,fracturecspacingofσc=–cmandanRMR(RockMassRatio,Bieniawski,)valueofapproximately–.TheSiOcontentintherockwasandthemeangrainsizemm.TheSchimazekindexwasatanaveragevalueofFs.N/mm.Therightwallwasalsosandysiltstone,butmorefracturedanditbrokebecauseofthediscontinuitieslicationindrivinggalleriesin.-m-thickcoalseams(minimum.m)inwhichpreviousroadheaderscouldnotbeused.Thestudydescribedherewascarriedoutinthecontextofthisproject.Duringtheadvanceofgalleriesin.-m-thickcoalseams,itwassometimesnecessarytoexcavatetherockoftheseamwalls,thestrengthofwhichwasalmostoverthelimitofthecuttingcapacityoftheroadheader.Itwasdecidedtoinvestigateif,undertheseconditions,theoperationorcuttingparameterswereacceptableusingtwodifferentcuttingheadsinthetest..Testdescription..TestobjectivesTheaimwastodeterminethepossibilityofdrivingthesegalleriesbymeansofa-kWroadheader,comparingtwodifferentcuttingheadsexcavatingthesametypeofrockinsimilaroperatingcycles.Themaindifferencebetweenthetwocuttingheadswasthenumberofpicks:thefirstcuttingheadhadpicks,whilethenewonehadonly(Fig.).Becauseofthelowernumberofcuttingtoolsincontactwiththerock,thetorquetransmittedbythemotorwastransformedtoalargertangentialforceinthepick,whichallowshigher-strengthrocktobecut.Stressconcentrationisthemajorfactorinrockfragmentation.Theparameterstomeasure(accordingtoclassicstudiesonthistheme；FowellandMcFeat-Smith,；Gehring,)arethecuttingrate(volumeofrockexcavatedpertimeunitinm/s),specificenergy(ener-gynecessarytoexcavateaunitofvolumeinMJ/m)andthetoolwearorspecificpickconsumption(picksorpickmasslostexcavatingaunitofvolumeofrockinpicks/morg/m).Allparametersweremeasuredwhentheroadheaderwasexcavatingcoalandrock,aswellaswhenitwasperformingotherpartsofthecycle...DescriptionoftheexcavatedfaceThecoalseamminedbythesublevelcavingmethodwasverticalanditsaveragethicknesswas.m.Withtheaimofcarryingoutthetestintheworstconditions,thetestzoneusedwasinanareawithaseamthicknessoflessthan.m.Athree-segmentsteelsetsupportwasused,thegallerybeingof.minwidthatthelowpartand.mhigh.InFig.sketchesoftheexcavatedfaceswiththe-pick(.m)and-pickcuttingheads(.m)areshown.Thecoalseamwas.and.mthick,respectively.Itwasformedbytwoveins:ontherightthecoalwassoft(σc＜MPa),whileontheleftthecoalwascstrong(σc=–MPa)withoutrockbetweenthem.CTheleftwallwasofsiltstone(sometimessandstone)withacompressivestrengthofssMPa,fracturecspacingofσc=–cmandanRMR(RockMassRatio,Bieniawski,)valueofapproximately–.TheSiOcontentintherockwasandthemeangrainsizemm.TheSchimazekindexwasatanaveragevalueofFs.N/mm.Therightwallwasalsosandysiltstone,butmorefracturedanditbrokebecauseofthediscontinuities似，大约是kW，但是工作用时间少了，同时可以观察到过量负荷持续了一个更长时间。在这个过程中，挖掘环有点轻微不同，有两个时间在右壁岩石上挖掘，第一个是在挖完软煤层后，第二个是在工作最后，巷道轮廓最终被挖掘出来时候。个新掘进头在工作完成之前重克，工作完成之后重为克，总共磨损了克。.结果.、特性切割能和切割速率用两个分析方法为两个不同截割头结果进行分析，第一，对分开不同类型岩石进行挖掘结果进行比较，第二，比较三个途径前进.m全部结果。第一个途径结果可以通过表.和表.观察出来，在计算中，当截割头在工作面上切割时候其它操作已经被分开考虑。变量包括：断面面积S（m）,掘进距离A（m），时间t（min），平均功率P（kW），在工作期间消耗，能量消耗E（MJ），切割速率CR和特性切割能SE（MJ/m）。在图.和图.，是功率需求方块图，两种类型岩石被选为例子，软煤和左壁岩石。根据操作不同进行切割，我们可以在方块图上看到频率出现最高功率是kW。在齿掘进机切割第一个途径，它在最后切割左边岩石壁，而且不要求其它操作。表.和表.反映了整个三个过程结果，图.是所有情况整个过程方块图。在一个整个工作周期中那个可以被称为是典型，两个掘进头切割速率都达到了m/h，这个结果符合其它研究结果（summarisedinCornejo；；Torano；）。这是掘进机在抗压强度σc=MPa半煤岩中掘进速率。如果巷道整个断面都是抗压强度σc=MPa岩石，掘进机要达到这个切割速率话它就需要kW功率，如果只有部分断面是岩石，也可以用kW掘进机。通过分析切割速率在不同岩石中达到值也可以得到相同结论。结果是切割岩石（净效率m/h或者考虑其它操作总效率为m/h），切割煤（净效率m/h或者考虑其它操作总效率为m/h），这些也符合其它研究成果。有意思是使用齿掘进机比齿掘进机效率高了超过，符合最近经验（Pichler,）。说到特性切割能，可以进行同样考虑。当在典型工作范围中，发现有价值东西可以同时用于两种类型掘进头。.—.MJ/m数据和过去研究相符合。这个大约是切割抗压强度σc=MPa，半煤岩含量＜岩石（Cornejo；）特性切割能。这个规律运用与其它类型岩石，软岩石和煤为.MJ/m，硬岩石为—MJ/m，都和其它研究在同一水平上（也许在煤特性切割能上有稍微有一点高）。在同样条件下，齿掘进机要好一点，消耗能量比齿掘进机大约少（符合Pichler；）。图.挖掘软煤层时功率需求（前齿后齿）图.挖掘左壁岩石时功率需求（前齿后齿）.、工具磨损（截齿消耗）在这个测试中，不能直接得到截齿消耗，因为切割这么小体积岩石不可能把截齿用完了，然而在测试时候，大众损失允许我们估计在哪个速率下，哪个掘进头会比另外一个掘进头用坏较大数目截齿。结果显示在表.从表.可以得出齿掘进机工具磨损比齿掘进机高出大约。考虑截齿总质量（大约g），假设它磨损掉总质量—就没有用了。.—.g/m消耗等同于.—.picks/m和.—.picks/m，这些数据和发表结果是一致（当特性切割能为—MJ/m时，.—.picks/m消耗正常）。这个结果也符合这台掘进机天天使用情况，齿掘进机消耗截齿比齿掘进机消耗高出，如表.所示。这个截齿消耗水平比软煤挖掘消耗要高（miningpotash,Ortega,,orminingcoal,Bermudez,)。然而它没有超过再次使用这台掘进机挖掘同样巷道做示范时挖掘岩石水平（Anon；）图.在三个过程中功率需求（前齿后齿）.结论从进行测试和从煤矿中得到经验,可以推出下列结论：、分析仅仅是挖掘岩石情况，齿掘进机切割速率比齿掘进机大约高出—，而且特性切割能明显低一些。、分析一般切割环也就是整个断面全部挖掘，齿掘进机切割速率比齿掘进机大约高出，而且需要更少特性切割能。、齿掘进机一个缺点是它工具消耗比齿掘进机高—。、齿掘进机另外一个观察到缺点是工作效率不高，其振动在掘进机中是处于比较高水平。一般说来，掘进机使用比较少齿截割头，将包含在较高切割速率和较大截割头消耗有一个平衡点，在这个事例煤矿中，使用齿掘进机优点是显然（因为切割速率比齿掘进机高，也就是每个月多挖掘—m，而仅仅多用了—个截割齿）。另一方面，可以推出下列一般结论：、因为在使用两种掘进头时候，所有操作因素都在正常水平上，所以可以用这种小功率掘进机来挖掘.m厚带坚硬岩石煤层巷道（还有其它优点，如少投资和小设备）。证明了在岩石切割抗压强度高达σc=MPa时（断面中岩石比例＜），使用掘进机挖掘小断面巷道和隧道是可行（Holeman，），这种应用将有利于在构造为一些弱岩石层和沉积岩普通隧道挖掘掘进机作为一种选用设备。licationindrivinggalleriesin.-m-thickcoalseams(minimum.m)inwhichpreviousroadheaderscouldnotbeused.Thestudydescribedherewascarriedoutinthecontextofthisproject.Duringtheadvanceofgalleriesin.-m-thickcoalseams,itwassometimesnecessarytoexcavatetherockoftheseamwalls,thestrengthofwhichwasalmostoverthelimitofthecuttingcapacityoftheroadheader.Itwasdecidedtoinvestigateif,undertheseconditions,theoperationorc中文字翻译部分英文原文AbstractInthispaper,theexperimentalresultsofa-kWand-troadheaderexcavatingagallerywithtwodifferenttypesofrockatthefaceusingtwodifferentcuttingheadsareshown.Itisprovedthattheroadheaderworksproperlywithbothcuttingheads.Incomparisonwithotherresultsintheliterature,theprincipalparameters,i.e.specificenergy,cuttingrateandtoolwear,areatalevelthatcanbeconsideredsatisfactorytakingintoaccountthelowpoweroftheroadheader.Ontheotherhand,theinfluenceofthenumberofpicks,whichisthemaindifferencebetweenthetwocuttingheads,ontheoperationalparametersisshown.ElsevierScienceLtd.Allrightsreserved.Keywords:Roadheaders；Cuttingheaddesign；Specificcuttingenergy；Cuttingrate；Toolwear.Introduction:experienceinusingofroadheadersinamineThecoalbasinintheNWofSpain(Arecesetal.,)formsasynclineinwhichthecoalseamsaremoderatelyinclined(–)attheNWfoldaxisandalmostvertical(–)attheSEfoldaxis.CarboniferousmaterialoccursunderaflatPermianoverburden,mthick.Theuseofroadheadersinthisminewasaconsequenceofmechanisationofthework.Coalminingbythelong-wallmethodwithpoweredroofsupportsmakesrapidadvanceoftheaccessroadsnecessary.Ontheotherhand,thetwoalternativesforminingverythickcoalseams,i.e.room-and-pillarinflatseamsandsublevelcavinginverticalseams,alsomakestheuseofroadheaderdrivinggalleriesinthecoalseamsnecessarySeveraltypesofroadheadersareusedinthemineforthesedifferentworks:a.Oneroadheader(Fig.)oftinweight,witha-kWrippingcuttinghead,especiallydesignedforthistypeofmineinthecontextofresearchproject(Anon.,；Toranoetal.,；Torano,)withtheobjectiveofdrivinggalleriesof-mcross-sectionsincoalseamsof.–.minthickness(withapprox.ofthesectioninhardrockofuniaxialcompressivestrengthuptosσc≈MPa)；b.Tworoadheaders(Fig.)oftinweight,witha-kWrippingcuttingheadmainlyusedindrivinggallerieswithmediumhardrock(σc≤MPa)orincroom-and-pillarmining；c.Tworoadheaders(Fig.)of.tinweightwithamillingcuttingheadofkW,onlyusedinadvancingofgalleriesincoal(softrock)；theconveyortypemeanstheroadheaderhasa.-mwidthandbecauseofthisitcanonlybeusedforadvancinggalleriesincoalseamsof.minthickness(mainlyintheminingmethodtermedsublevelcaving)；andd.Oneroadheader(Fig.)of.tinweightwitha-kWmilling-typecuttinghead,developedwiththisnarrowdesignespeciallyforthismine(Toranoetal.,)foritsapplicationindrivinggalleriesin.-m-thickcoalseams(minimum.m)inwhichpreviousroadheaderscouldnotbeused.Thestudydescribedherewascarriedoutinthecontextofthisproject.Duringtheadvanceofgalleriesin.-m-thickcoalseams,itwassometimesnecessarytoexcavatetherockoftheseamwalls,thestrengthofwhichwasalmostoverthelimitofthecuttingcapacityoftheroadheader.Itwasdecidedtoinvestigateif,undertheseconditions,theoperationorcuttingparameterswereacceptableusingtwodifferentcuttingheadsinthetest..Testdescription..TestobjectivesTheaimwastodeterminethepossibilityofdrivingthesegalleriesbymeansofa-kWroadheader,comparingtwodifferentcuttingheadsexcavatingthesametypeofrockinsimilaroperatingcycles.Themaindifferencebetweenthetwocuttingheadswasthenumberofpicks:thefirstcuttingheadhadpicks,whilethenewonehadonly(Fig.).Becauseofthelowernumberofcuttingtoolsincontactwiththerock,thetorquetransmittedbythemotorwastransformedtoalargertangentialforceinthepick,whichallowshigher-strengthrocktobecut.Stressconcentrationisthemajorfactorinrockfragmentation.Theparameterstomeasure(accordingtoclassicstudiesonthistheme；FowellandMcFeat-Smith,；Gehring,)arethecuttingrate(volumeofrockexcavatedpertimeunitinm/s),specificenergy(ener-gynecessarytoexcavateaunitofvolumeinMJ/m)andthetoolwearorspecificpickconsumption(picksorpickmasslostexcavatingaunitofvolumeofrockinpicks/morg/m).Allparametersweremeasuredwhentheroadheaderwasexcavatingcoalandrock,aswellaswhenitwasperformingotherpartsofthecycle...DescriptionoftheexcavatedfaceThecoalseamminedbythesublevelcavingmethodwasverticalanditsaveragethicknesswas.m.Withtheaimofcarryingoutthetestintheworstconditions,t        中文4757字翻译部分英文原文AbstractInthispaper,theexperimentalresultsofa45-kWand15-troadheaderexcavatingagallerywithtwodifferenttypesofrockatthefaceusingtwodifferentcuttingheadsareshown.Itisprovedthattheroadheaderworksproperlywithbothcuttingheads.Incomparisonwithotherresultsintheliterature,theprincipalparameters,i.e.specificenergy,cuttingrateandtoolwear,areatale

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