Cosen C3 User manual

COSEN SAWS
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C3
NCFullyAutomatic
HorizontalBandsaw
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(Non‐CE&CEModels)
InstructionManual
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ThePinnacleofCuttingPerformance
CosenMechatronicsCo.,Ltd.

i
NOTE:
Read this instruction manual carefully to familiarize yourself with the installation, operation
and maintenance of your COSEN bandsaw machine.
Operate the machine following the procedures described in the manual to prevent personal
injuries or machine damage.
Keep this manual handy and refer to it whenever you are uncertain of how to perform any of
the procedures.
For technical support or parts purchase, please contact your nearest COSEN representative or
our service center:
For US, Mexico, and Canada:
email: [email protected].
phone: [phone]
toll free: 1-877-SAWING1
fax: [phone]
For service in other countries:
email: [email protected]
phone: [phone]
fax: [phone]
Instruction Manual: C3
NC Fully Automatic Horizontal Bandsaw
Ver. 8 2017/06/13
©2013 by COSEN MECHATRONICS CO., LTD.
No part of this publication may be photocopied or otherwise reproduced without the prior written permission of COSEN.
Printed in Taiwan
FROM THE MANUFACTURER
Thank you for your purchase of COSEN’s bandsaw machine and your trust in the
COSEN brand.
We are excited to have you as our valued customer and look forward as much as
you do to the accelerated productivity, long-lasting endurance and superb
cost-effectiveness this machine is about to bring to you.
To ensure you are fully utilizing our machine and being advantaged in every possible
way, please do take your time and read through this instruction manual.
Any comment or suggestion in making our service better, please do not hesitate to
let us know. Thank you again!

ii
Safety rules


Makesureyourworkareaiscleared
ofuninvitedpeopleandobstacles
everytimebeforeyoustart
operatingthemachine.
Neverwearglovesorlooseclothing
whenoperatingthemachine.Itmay
leadtoseriousinjuryiftheyare
caughtintherunningmachine.Wrap
orcoverlonghair.

Useawater‐solublecuttingfluidon
thismachine.Oil‐basedcuttingfluids
mayemitsmokeorcatchfire,
dependingonhowtheyareused.

iii
Safety rules

Nevercutcarbonoranyother
materialthatmayproduceand
disperseexplosivedust.Itispossible
thatsparksfrommotorsandother
machinepartswilligniteandexplode
theair‐bornedust.

Makesureanyuseoffireis
prohibitedintheshopandinstalla
fireextinguisherorotherfirecontrol
devicenearthemachinewhen
cuttingtitanium,magnesium,orany
othermaterialthatproduces
flammablechips.Neverleavethe
machineunattendedwhencutting
flammablematerials.

Neveradjustthewirebrushor
removechipswhilethesawbladeis
stillrunning.Itisextremely
dangerousifhandsorclothingare
caughtbytherunningblade.

Nevertouchtherunningsawblade
withglovesornot.Itisdangerousif
yourhands,clothingorglovesare
caughtbytherunningblade.

iv
Safety rules

Stopthesawbladebeforeyouclean
themachine.Itisdangerousifhands
orclothingarecaughtbytherunning
blade.

Neverstartthesawbladeunlessthe
workpiecehasbeenclampedfirmly.
Iftheworkpieceisnotsecurely
clamped,itwillbeforcedoutofthe
viseduringcutting.

Takepreventivemeasureswhen
cuttingthinorshortpiecesfromthe
worktokeepthemfromfalling.Itis
dangerousifthecutpiecesfall.

v
Safety rules

Userollertablesatthefrontandrear
sidesofthemachinewhencutting
longwork.Itisdangerousifthework
piecefallsoffthemachine.

Neversteporstandontheroller
table.Yourfootmaysliportripon
therollersandyouwillfall.

Turnofftheshopcircuitbreaker
switchbeforeperforming
maintenanceonthemachine.Posta
signindicatingthemachineisunder
maintenance.


vi
T
able of Contents

Section1–SafetyInformation1‐1
SafetyInstructions…………………………………………………………………………………………………….. 1‐1
SafeguardDevices……………………………………………………………………………………………………… 1‐3
EmergencyStop………………………………………………………………………………………………………… 1‐4
Illustration:EmergencyStop……………………………………………………………………………………… 1‐5
SafetyLabels…………………………………………………………………………………………………………….. 1‐6
Illustration:SafetyLabels………………………………………………………………………………………..… 1‐9
HearingProtection…………………………………………………………………………………………………….. 1‐10
CECompliance………………………………………………………………………………………………………….. 1‐10
RiskAssessment……………………………………………………………………………………………………….. 1‐10
Section2–GeneralInformation2‐1
Specification……………………………………..……………………………………………………………………..2‐2
MachinePartsIdentification……………………………………………………………………………………… 2‐3
FloorPlan…………………………………………………………………………………………………..……………… 2‐4
Section3–Moving&Installation3‐1
Location&Environment………………………………..………………………………………………………….. 3‐1
Unpacking&Inspecting……..……………………………………………………………………………………… 3‐2
Lifting…………………………………………..………………………………………………………………….………… 3‐3
Picture:LiftingPoints…………………………………………………………………….………….3‐5
RemovingShippingBracket…………………………..……………………………………………….………….. 3‐6
Cleaning…………………………………………..…………………………………………………………….………….. 3‐6
Installing…………………………...………………………………………………………………………….…………… 3‐6
SupplyingHydraulicOil…………………………………………………………………….…………… 3‐6
SupplyingCoolant………..………………………………………………………………….…………… 3‐7
ConnectingElectricPower……………………………………………………………….……………. 3‐7
Leveling&Anchoring…………………………………………………………………….………………. 3‐8
InstallingRollerTable(Optional)………………………………………………….………………… 3‐9
InstallingFireControlDevice…………………………………………………………………………… 3‐9
Relocating………………………...…………………………………………………………………….………………… 3‐9
Section4–OperatingInstructions4‐1
SafetyPrecautions…………………..…………………..……………………………………….………………….. 4‐2
BeforeOperating…………………………..…………………………………………………………………………… 4‐3
ControlPanel……..……………………………………..………………………………………….…………………… 4‐4
ControlPanel………………….………………………………………………………………………..…… 4‐4
ControlButtons……………………………………………………………………………………….…… 4‐5

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able of Contents
BladeDescendPressure&Speed………..…………………………………………………….…. 4‐7
HMITouchScreen&Functions…………………………………………………………….………. 4‐7
HMIErrorCodes………………………..……………………………………………………….………… 4‐20
StandardAccessories………….………………………..……………………………………………….………….. 4‐21
OptionalAccessories…….…….………………………..…………………………………………….…………….. 4‐24
Unrolling&InstallingtheBlade…………………………………………………………………….…………… 4‐26
AdjustingWireBrush………..……………………………………………………………………….……………… 4‐28
AdjustingSawArm……………..……………………………………………………………………….……………… 4‐28
AdjustingBladeSpeed………..………..…………………………………………………………………………… 4‐29
Breaking‐IntheBlade………..………..…………………………………………………………………..………… 4‐29
PlacingWorkpieceontoWorkbed………………………..……..………..…………………………………… 4‐29
PositioningWorkpieceforCutting………..………..………………………………….……………………… 4‐30
WithoutUsingAutomaticFirstCutFunction…………………………………………………. 4‐30
UsingAutomaticFirstCutFunction………………………………………………………………… 4‐31
AdjustingCoolantFlow………..………..…………………………………………………………………..……… 4‐32
Test‐RunningtheMachine....………..……………………………………………..…………………………… 4‐33
CuttingOperation………..………..……………………………………………..…………………………………… 4‐34
UsingTopClampforBundleCutting…………………………………………………………………………… 4‐35
TerminatingaCuttingOperation………..………..…………………………………….……………………… 4‐36
Section5–ElectricalSystem5‐1
ElectricalCircuitDiagrams……….…………………..…………………………………………………………..5‐1
Section6–HydraulicSystem6‐1
HydraulicDiagrams……….…………………..……………………………………………………………………….. 6‐1
Section7–BandsawCutting:APracticalGuide7‐1
Introduction……………………….…….…………………..………………………………………………………….. 7‐1
SawBladeSelection………………….…………………..………………………………………………………….. 7‐1
SomeSawingPractices…………….…………………..………………………………………….……………….. 7‐4
SawPitchSelection……………………………………………………………………….……………… 7‐4
MaterialSizeandSawPitch………………………………………………….….…………………… 7‐4
Section8–Maintenance&Service8‐1
Introduction……………………….…….…………………..………………………………………………………….. 8‐1
BasicMaintenance………………….…………………..…………………………………………….……………..8‐1
MaintenanceSchedule…………….…………………..…………………………………………………………..8‐1
BeforeBeginningaDay’sWork……………………………………………………………………… 8‐2
AfterEndingaDay’sWork…………………………………………………….………………………8‐2
EveryMonth………………………………………………………………………….……………………… 8‐2

viii
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able of Contents
EveryThreeMonths………………..…………………………………………….……………………… 8‐2
EverySixMonths……………….………………………………………………….……………………… 8‐3
StorageConditions…………………………....………..…………………………………………………………..8‐3
TerminatingtheUseofMachine……..…………..…………………………………………………………..8‐3
OilRecommendationforMaintenance……………………………………………………………………..8‐4
Section9–Troubleshooting9‐1
Introduction……………………….…….…………………..………………………………………………………….. 9‐1
Precautions………………….…………………..…………………………………………………………………….... 9‐2
GeneralTroubles&Solutions………………………..………………………………………………………….. 9‐2
MinorTroubles&Solutions………………………..………………………………………………..…………..9‐3
MotorTroubles&Solutions………………………..…………………………………………………..……….. 9‐3
BladeTroubles&Solutions………………………..……………………………………………………………..9‐4
SawingProblems&Solutions………………………..………………………………………………………….. 9‐5
Re‐AdjustingtheRollerTable………………………..………………………………………………………….. 9‐6
Section10–Parts10‐1
SparePartsRecommendations…………………..…………………………………………………………….. 10‐1
PartList…………………..…………………………………………………………………………………………………. 10‐2
Section11–Warranty11‐1
Warranty…………………..……………………………………………………………………………………………….. 11‐1
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

1‐1
Section1
SAFETY
INFORMATION

SAFETYINSTRUCTIONS
SAFEGUARDDEVICES
EMERGENCYSTOP
SAFETYLABELS
HEARINGPROTECTION
CECOMPLIANCE
RISKASSESSMENT

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Safetyisacombinationofawell‐designedmachine,operator’sknowledgeaboutthemachineand
alertnessatalltimes.COSEN’sbandmachinehasincorporatedmanysafetymeasuresduringthe
designprocessandusedprotectivedevicestopreventpersonalinjuriesandpotentialrisks.Warning
labelsalsoserveasaremindertotheoperator.

Throughoutthismanual,youwillalsoseevarioussafety‐relatedsymbolsindicatingimportant
informationthatyoushouldtakenoteofpriortouseofthemachineorpartofitsfunctions.These
importantsafetyinstructionsdonotcoverallpossiblesituationsthatmightoccur.Itisyour
responsibilitytotakecautionandfollowproceduresstatedinthismanualwheninstalling,
maintainingandoperatingyourmachine.Cosenwillnotbeliablefordamagesresultingfrom
improperuse.


SAFETYINSTRUCTIONS
Whattheiconsandsignsinthisusermanualmean:

ThisiconmarksDANGER;hazardsorunsafepracticesthatmayresultinsevere
personalinjuryordeath.

ThisiconmarksWARNING;hazardsorunsafepracticesthatmayresultin
personalinjuryordamagetothemachine.

ThisiconmarksCAUTION;informationthatshouldbereadbeforeusetoprevent
damagetothemachine.
Supplementaryinformationtotheproceduresdescribedinthismanual.
Callyourlocalagentorourservicecenterforhelp.

1‐2


Thismanualhasimportantsafety
information.Readthroughitcarefully
beforeoperatingthismachinetoprevent
personalinjuryormachinedamage.Learn
theoperation,limitationandthespecific
potentialhazardspeculiartothisband
saw.

Donotoperatethismachineunlessitis
completelyassembled.

Makesurethepowerswitchisoffbefore
plugginginpowercord.

Disconnectthepowercordbeforemaking
adjustment,maintenanceorblade
changes.

Keepallguardsandshieldsinplacebefore
installingorstartingupthemachine.

Wearproperapparelduringoperation
andwhenservicingthemachine.
Keepunauthorizedpersonnelaway.

Donotreachoverorstandonanypartof
themachine.

Neverholdthematerialbyhandfor
cutting.Alwaysusetheviseandmake
surethematerialisclampedsecurely
beforecutting.

Itisdangeroustooperatethemachine
whenthefloorisslippery.Keepthefloor
cleananddry.Checkforice,moisture,or
greasebeforeentering.

Donotusethemachinetocutexplosive
materialorhighpressurevesselsasitwill
generategreatamountofheatduringthe
sawingprocessandmayignitean
explosion.

Keeptheworkenvironmentsafe.Donot
usebandsawinadamporwetlocation.

Neveroperatewhileundertheinfluence
ofdrugs,alcoholormedication.

Allusersmustreaditbeforeperformingany
activityonthemachine,suchasreplacing
thesawbandordoingregularmaintenance.
Somepersonalprotectiveequipmentis
requiredforthesafeuseofthemachine,e.g.
protectiongoggles.
Keepbladeprotectioncoverandwheel
coversinplaceandinworkingorder.
Userecommendedaccessories.Improper
accessoriesmaybehazardous.
Keepyourworkareawellilluminatedat
minimum500lumen.
Keepyourworkareaclean.Clutteredand
slipperyfloorsinviteaccidents.
Removeadjustingkeys,wrenchesorany
loosepartsoritemsfromthemachine
beforeturningonpower.
Checkfordamagedparts.Beforecontinuing
usingthemachine,thedamagedpartshould
becheckedandreplaced.
Movingpartsshouldbekeptinproper
alignmentandconnectionwiththemachine.
Checkforbreakage,mountingandanyother
conditionsthatmayaffectitsoperation.Any
damagedpartorguardshouldbeproperly
repairedorreplaced.
Whenaworkpieceistoolongorheavy,
makesureitissupportedwitharollertable
(recommended).
Alwaysremembertoswitchoffthemachine
whentheworkiscompleted.
Useasharpsawbladeandkeepthemachine
initsbestandsafestperformanceby
followingaperiodicalmaintenanceschedule.
Donotforcethebandsawbeyondits
intendeduse.Itissafertooperatewiththe
cuttingrateforwhichitwasdesigned.


1‐3
SAFEGUARDDEVICES
Thesafeguarddevicesincorporatedinthismachineincludethefollowingtwomainparts:
1. Protectioncovers&guards
2. Safety‐relatedswitches

ProtectionCovers&Guards
1. Idlewheelhousingcover
2. Drivewheelhousingcover
3. Gearreducercover
4. Wirebrushbeltcover
5. Bladeguardcover(left&right)
6. Chipconveyorcover(CEmodelonly)

Theprotectiondevicesshouldalwaysbemountedonthemachinewheneverthemachineisrunning.
Donotremoveanyofthesesafeguarddevicesunderanycircumstancesexceptwhenservicingthe
machine.Evenskilledservicetechniciansshouldstilltakecautionswhenperformingrepairsorservice
onthemachinewithanyoftheseprotectorsremoved.Itistheresponsibilityoftheusertomakesureall
theseelementsarenotlostanddamaged.
Takenoteofthefollowingmainmovingpartsonthemachinepriortoandduringmachineoperation:
Sawbowassembly
Driveandidlewheels
Bladeguidearm
Sawbladeguiderollers
Quickapproachdevice
Wirebrush
Chipconveyor(optional)
Workpiececlampingvises
Shuttlevisesandworkbedrollers
Topclamps(optional)
Gearreducer


1‐4
SafetyRelatedSwitches
Toprotecttheoperator,thefollowingsafetyrelatedswitchesonthemachineareactuatedwhenthe
machineisinoperation.

WheelmotiondetectorThisisaproximitysensorusedtodetectthemotion
ofthedrivewheel.Oncethesawbladeisbrokenor
assoonasitstartsslipping,thesensorwilldetect
andstopthedrivewheelandthemachine.
PowerswitchLocatedonthecoverofelectricalcabinet,thepower
switchcontrolsthemainpowerofthemachine.Up
toyourcompany’sinternalrules,thispowerswitch
canbelockedwithapadlockoraluggagelockto
protecttheoperatorandthemachine.
EmergencystopbuttonLocatedonthecontrolpanel,thebuttonwhen
pressedwillstopthemachinecompletely.
ViseclampswitchThisswitchassuresfirmclampingoftheworkpiece.If
theworkpieceisnotclampedproperly,thesaw
bladeisnotallowedtorun.
Wheelcoverinterlockswitches
(CEmodelonly)
Locatedonthetwowheelhousings,theseswitches
areusedtoassurethatthemachinewillstop
wheneverthewheelcoversareopen.Thisdeviceis
toprotectusersfrombeingcutbytherunningsaw
blades.

Amongallthesesafetyswitches,someofthemareusedtoprotecttheusersandsomeofthemare
usedtopreventdamagetosawblades,theworkpieceandthemachineitself,etc.Wehavetaken
everyprecautiontopreventinjuryordamageandtoprovidesafeandeconomicaloperationofthe
machine.


EMERGENCYSTOP
Designedtobeeasilyaccessible,theemergencystopbuttonislocatedontheleftbottomcorneron
thecontrolpanelandismadeinredcolorandrubbermaterial.ForCEmodels,supplementary
emergencystopbuttonmaybeavailableatotherarea(s)ofthemachinedependingonmachinetype.
PleaserefertoIllustration:EmergencyStop.
Whenyoupressthebutton,themachinewillimmediatelycometoafullstoptoavoidinjuryor
damagewhenanaccidentoccurs.Thebuttonwillbelockedwhenyoupressit.Tounlockit,pullit
upward.
Youshouldpressitimmediatelywithoutanyhesitationwhenobserving:
Anemergencysituationthatwouldcauseanyinjuryordamage
Anabnormalsituationorproblemsuchasfire,smoke,abnormalnoiseandetc.

1‐5
Illustration:EmergencyStop



EmergencyStop
急停按鈕

1‐6
SAFETYLABELS
Safety‐relatedlabelsmountedonthemachinearecategorizedintothefollowingfourcategories.
Pleasereadthroughandunderstandthembeforeoperatingthemachine.RefertoIllustration:Safety
Labels.

DANGERLabels
AredandwhiteDANGERlabelsmarksshazardsorunsafepracticesthatwillresultinseverepersonal
injuryordeath.
LabelMeaningLabelMeaning

HazardousVoltage

TURNPOWEROFFbefore
servicing.Failureto
followingthewarningcan
resultinsevereinjury.

DANGER:RunningBlade
Bladerunsthroughthisarea.Keep
yourhandsawayfromarunning
bladetoavoidsevereinjury.The
arrowindicatesdirectionofthe
blade.


WARNINGLabels
AnorangeandblackWARNINGlabelmarkshazardsorunsafepracticesthatcanresultinsevere
personalinjuryordamagetothemachine.
LabelMeaningLabelMeaning

CuttingHazard

KEEPCOVERCLOSEDwhile
thebladeisrunning.Turn
poweroffbeforeopening
cover.Failuretofollowthe
warningcanresultinsevere
injury.
CuttingHazard

KEEPHANDOFFwhilethebladeis
running.Turnpoweroffbefore
openingcover.Failuretofollowthe
warningcanresultinsevereinjury.


Pleaseaddantifreeze
coolantwhentheambient
temperatureisbelow0˚C
(32˚F).

LooseHandHazard

KEEPHANDOFF.Donottouchchip
conveyor.Failuretofollowthe
warningcanresultinsevereinjury.

ImpactHazard

WEARSAFETSHOES.Donot
approachdroppingarea
duringoperation.



1‐7
CAUTIONLabels
YellowandblackCAUTIONlabelsmarkhazardsorunsafepracticesthatcanresultin
considerablepersonalinjury.
LabelMeaning

Keephandsoutofthemachinewhilethebladeisrunning.

Powertomachinemustbeturnedoffwhenchangingbladesor
adjustingwirebrush.


NOTICELabels
BlueandwhiteNOTICElabelsmeanunsafepracticesthatcouldresultindamagetoproductsor
property.
LabelMeaning

Replacethehydraulicoileverysixmonthsorevery1,200hours
ofoperation.

Oilspecification:ShellTELLUS27orMobilDTEOILLIGHT/
HYDRAULIC28

Toextendbladelife,alwaysadjustthelocationofwirebrushso
thatitisproperlytouchingtheblade.Alsoreplaceawornwire
brushwithanewone.



1‐8
SAFETYINSTRUCTIONLabels
GreenandwhiteSAFETYINSTRUCTIONSareimportantremindersthatshouldbereadbefore
operatingthemachine.
LabelMeaning
1. Readandunderstandtheinstructionmanualandwarning
signsbeforeoperatingmachine.Failuretofollowthese
instructionsandwarningscanresultinseriousinjuryor
death.
2. Donotweargloves,neckties,jewelryorlooseclothing
whileoperatingthemachine.
3. Alwaysweareyeprotectiongoggles.
4. Checkbladetensionandadjustbladeguidebeforestarting
tocut.
5. Alwaysclampstockfirmlyinplacebeforecutting.
6. Donotremovejammedorcut‐offpiecesuntilbladehas
stopped.
7. Keepfingersoutofpathofblade.
8. Bladeguardsshouldbeinplaceandusedatalltimes.
9. Disconnectmachinefrompowersourcebeforemarking
repairsoradjustments.
10. Donotoperatewhileundertheinfluenceofdrugs,alcohol
ormedication.


1‐9
Illustration:SafetyLabels


1‐10
HEARINGPROTECTION
Noisehasamajoreffectonthequalityofyourworkenvironment.Herewereferyoutotestingdata
andinformationasfollows:
Excessiveexposuretohighlevelsofnoisemaycauseimpairmenttohearing,butthevulnerabilityto
hearinglossvariesbetweenindividualsandmustbetakenintoaccountinspecifyinganallowable
limitfornoiseexposure.
Alevelof90dBAiswidelyacceptedasacriterionfor8hour/dayexposuretosteady‐statebroad‐
bandnoise.Theunprotectedearshouldnotbeexposedtonoiselevelshigherthan120dBA.
Noisegeneratedbythemachinemaycomefromthefollowing:
Sawbladeduringcuttingormaterialfeedmechanism
Wirebrushunit
Chipconveyorunit
Speedreducer
Hydraulicmotor/pump
Belttransmissionsvariablespeedmotors
Blademotor
Coolantpump
Drivewheel
Partsnotassembledtightlycausingmechanicalvibration

Whenyourmachineisrunning,noisewillcomeout.Thisisamachine‐electricinterfaceproblemthat
maymakepeoplefeeluncomfortable.Ourproductspassnoisetestinglessthan78dBA.Ifyour
machineproducesanundesirablenoisewhileitisrunning,youshould:
1. Makesureallmaintenancetaskshavebeenperformedfollowingtheprescribedmaintenance
schedule(RefertoSection7)
2. Ifmaintenancedoesnotseemtosolvetheproblem,followthetroubleshootingprocedures
underSection8.


CECOMPLIANCE
Cosen’sCEmodelisdesignedtosatisfyregulationsoftheCouncilDirectiveontheapproximationof
thelawsoftheMemberStatesrelatingtomachinery(2006/42/EC)‐AnnexIEssentialhealthand
safetyrequirementsrelatingtothedesignandconstructionofmachinery.

RISKASSESSMENT
Riskassessmentgenerallytakesaccountofintendeduseandforeseeablemisuse,includingprocess
controlandmaintenancerequirements.Wemadeeveryefforttoavoidanypersonalinjuryor
equipmentdamageduringthemachinedesignstage.However,theoperator(orotherpeople)still
needstotakeprecautionswhenhandlinganypartofthemachinethatisunfamiliarandanywhereon
themachinethathaspotentialhazards(e.g.theelectricalcontrolbox).

2-1
Section 2
GENERAL
INFORMATION
SPECIFICATION
MACHINE PARTS IDENTIFICATION
FLOOR PLAN
This band saw machine is designed by Cosen’s R&D engineers to provide you the following features
and advantages:
Safety
This machine is designed to fully protect the operator from its moving parts during cutting
operation.
The machine and each compoment has passed strict testing (Council Directive on the
approximation of the laws of the Member States relating to Machinery).
The machine will shut off automatically when the saw blade is broken, protecting both the
operator and the machine.
Convenience & High-Performance
The machine is designed in the way that the operation and adjustment can be easily
performed.
The machine will stop automatically when out of stock.
Dual valve system is designed to achieve optimal cutting performance with the simple
setting of feed rate and perspective cutting pressure for different material.
Durability
The intended life-span of the machine is counted based on regular daily operation. It is
calculated with the life expectancy of 10 years under normal operating condition and exact
attention to the maintenance schedule.
8 hours × 5 days × 52 weeks × 10 years ＝20,800 hours