lecture notes

1. Agriculturalmachinerysection(daelp)
WORKSHOPTECHNOLOGYTRAINING
AGRICULTURALMACHINERYSECTION
(AE110)

2. Agriculturalmachinerysection(daelp)
1:GENERALWORKSHOPRULES
a)Personalsafety
 Alwaysbepatient,neverrushintheworkshop.
 Alwayslistencarefullytotheinstructorandfollowinstructions.
 Alwaysuseaguardwhenworkingonamachine.
 Alwayswearanapron(overcoat)asitwillprotectyourclothesandholdslose
clothingsuchastiesinplace.
 Bagsshouldnotbebroughtintoaworkshopaspeoplecantripoverthem.
 Donotrunintheworkshop,youcould‘bump’intoanotherstudentandcause
anaccident.
 Donotuseamachineifyouhavenotbeenshownhowtooperateitsafelyby
theinstructor.
 Hearingprotectionshouldbewornwhenusingmachinery.
 Keephandsawayfrommoving/rotatingmachinery.
 Knowwheretheemergencystopbuttonsarepositionedintheworkshop.If
youseeanaccidentattheothersideoftheworkshopyoucanusethe
emergencystopbuttontoturnoffallelectricalpowertomachines.
 Longhairmustbetiedback.
 Reportanydamagetomachines/equipmentasthiscouldcauseanaccident.
 Safetyfootwear(shoes)mustbewornwhenworkingintheworkshop.
 Safetyglassesmustbeworn.
 Usehandtoolscarefully,keepingbothhandsbehindthecuttingedge.
 Whenattemptingpracticalworkallstoolsshouldbeputaway.
 Whenlearninghowtouseamachine,listenverycarefullytoallthe
instructionsgivenbytheinstructor.Askquestions,especiallyifyoudonot
fullyunderstand.

3. Agriculturalmachinerysection(daelp)
b)Tractorsafety
 Knowyourtractor,itsimplementsandhowtheywork.Keepyourtractoringood
condition.
 Mosttractorfatalitiesarecausedbyoverturns.Ifyoudon’tmatchtractorwith
load
 Befamiliarwithyourterrainanddrivesafely.Usecautiononslopes,slowdown
forallturnsandstayoffthehighwaywheneverpossible.
 Neverstartanengineinaclosedshedorgarage.Carbonmonoxideiscolorless,
odorlessanddeadly.
 AlwayskeepyourPTOproperlyshielded.Itrotateswiththestrengthof500men.
 Keepyourhitcheslowandalwaysonthedrawbar.Otherwiseyourtractormight
flipoverbackwards.
 Neverjumpoffamovingtractororleaveitwithitsenginerunning.Arunaway
tractorcanbeextremelydangerous.
 Neverrefuelwhiletheengineisrunningorhot.Anddonotaddwatertoradiator
whiletheengineishot;hotwatercaneruptandscald.
 Keepallchildrenoffofandawayfrom yourtractoranditsimplementsatall
times.Atractor’sworkisnotchild’splay.
 Neverbeinahurryaboutanythingtodowithyourtractor.Takeyourtimeanddo
itright.

4. Agriculturalmachinerysection(daelp)
2:GENERALDESIGNOFTRACTORANDAUTOMOBILES
2.1Classificationofautomobileandtractors
Automobile(cartruck)isaselfpropelledvehicleintendedfortransportinggoods,
peopleandforcarryingoutspecialtasks.
Astopurpose,motorvehiclesaredividedintotransportvehicles,special-
purposevehicles,andcompetitionvehicles.
i. Transportvehiclesareclassedinseveraltypes;
 Cars-Motorvehiclesintendedforcarryingsmallgroupofpeople(upeight
innumber);
 Buses-passengersservicevehicles(morethaneightinnumber);
 Truck-Motorvehiclesintendedforcarryingvariouscargos
Accordingtocargos(loadingcarryingcapacity)truckaredividedintothefollowing
classes:
 Pick-uptruck(upto0.5ton)
 Lighttruck(1to2t)
 Mediumtruck(2to5t)
 Heavytruck(5to15t)
 Overweighttruckmore15t
ii. Special-purposevehicles
Asthenameimpliesthisgroupincludestruckcranes,tanktruck,seed-filler
trucketc.
iii. Competitionvehicles
Thesearecarsspeciallydesignedforracing

5. Agriculturalmachinerysection(daelp)
Astothetypeofchassis,motorvehiclesmayeitherframedorframeless.
 Framevehicleshaveasupportstructure,calledframe,towhichall
componentareattached.
 Frameless(unit-construction)vehicleshavenoframe,andalltheir
componentpartsareattacheddirectlytothevehiclebody.
 Astoprimemover,automobilemaybedividedintopetrol-powered,diesel
poweredorbatterypowered(electricmotors).
Tractor
Thetractorisawheeledortrackedself-propelledvehicleusedasapowermeans
formovingagricultural,road-building,andothermachinesequippedwithspecial
tools,andalsotowingtrailers.Itcanpowerstationarymachinethrough(PTO,or
beltpulley)
Theusesofthetractorinagriculturearemany,andsodifferenttypesoftractor
areneededtododifferenttypesoffarmwork.
 Astopurpose
Modernfarmtractorsareclassedinthreegroups:
 Generalpurpose(land-utilitytractors)usedformajorfarm operations
commontothecultivationofmostcrops,suchasgeneralcultivation,
harrowing,sowingandharvesting.Arecharacterizedbylow ground
clearance,increasedenginepower,goodtractionandthushighpull
fromwidetires.
 Universal-row-croptractorsareintendedforrow-cropworkaswellas
formany otherfield tasks.Are characterized with high ground
clearance,replaceabledrivingwheelsofdifferenttreadwidths–wide
forgeneralfarmworkandnarrowforrow-cropwork.
 Specialpurpose tractors are modifications ofstandard land or
row–croputilitytractormodelsfordefinitejobssuchasincotton

6. Agriculturalmachinerysection(daelp)
(singlefrontsteerablewheel)andvineyardsfieldsorforvariousjobs
undercertainconditionse.g.onmarshysoils(widetracks),hillsides
(16
o
).
 Astothedesignoftherunninggeartractoraredividedintocrawler(track
-laying)andwheeledtypes
Crawlertractorsaredistinguishedbyalargegroundcontactareaand
thereforehavetrackadhesionwhilewheeledtractorsareversatileand
canbeusedforbothfieldandtransportwork,buttheirtractionislower
thanthatofcrawlertractors.
Astothetypeofundercarriage,tractorsmaybeframed,semi-framedor
frameless.Thebodyofframedtractorsisessentiallyarivetedorwelded
frame,thatofsemi-framedtractorsismadeupoftwoshortlongitudinal
beams(sidemembers)boltedor weldedtotherearaxlehousing,whilein
framelesstractors,thebodyisformedbyboltingtogetherthecasingsof
individualtractormechanisms.
2.2MainComponentspartsoftractorandautomobile
Boththetractorandtheautomobileareself-propelledmachinesconsistingof
separateinteractingmechanismsandunitsthatcanbecombinedintocertain
groups.
 Maincomponentspartsofthetractor
1-Engine,2-steeringmechanism,3-Auxiliaryequipment,4-driveline,5-working
(live)attachmentsand6-runninggear
 MaincomponentspartsoftheAutomobile
1-Drive’s cab,2-cargo body 3-clutch,4-transmission (gearbox)5-
propeller(cardan)shaftand6-finaldrive(drivingaxle)

7. Agriculturalmachinerysection(daelp)
3:BASICSOF
DIESELAND
PETROL
ENGINES
----------
The four-stroke
dieselengineissimilartothefourstrokepetrol(gasoline)engine.Theyboth
followanoperatingcyclethatconsistofintake,compression,power,andexhaust
strokes.Theyalsosharesimilarsystemsforintakeandexhaustvalves.Seefigs.
1.and2.

8. Agriculturalmachinerysection(daelp)
Figure1:Asectionofdieselengineblockandcylinderheadforinternaldetails
Figure2:Asectionofpetrolengineblockandcylinderheadforinternaldetails

9. Agriculturalmachinerysection(daelp)
A:Theprimarydifferencesbetweenadieselengineandapetrolengineareas
follows:
•Thefuelandairmixtureisignitedbytheheatgeneratedbythecompressionstroke
inadieselengineversustheuseofasparkignitionsystemonapetrolengine.
•Thefuelandairmixtureinadieselengineiscompressedtoaboutonetwentiethof
itsoriginalvolume,whileinapetrolenginethefuelandairmixtureisonly
compressedtoaboutoneeighthofitsoriginalvolume.Thedieselenginemust
compressthemixturemoretightlytogenerateenoughheattoignitethefueland
airmixture.
•Thepetrolenginemixesthefuelandairbeforeitreachesthecombustionchamber.
Adieselenginetakesinonlyairthroughtheintakeport.Fuelisputintothe
combustionchamberdirectlythroughaninjectionsystem.Theairandfuelthen
mixinthecombustionchamber.
•Theenginespeedandthepoweroutputofadieselenginearecontrolledbythe
quantityoffueladmittedtothecombustionchamber.Theamountofairis
constant.Onthepetrolengine,thespeedandpoweroutputisregulatedby
limitingtheairandfuelmixtureenteringtheengine.
Adieselengineismuchmoreefficientthanapetrolengine,suchasthediesel
enginedoesnotrequireanignitionsystem duetotheheatgeneratedbythe
highercompression,thedieselenginehasabetterfueleconomyduetothe
completeburningofthefuel,andthedieselenginedevelopsgreatertorquedue
tothepowerdevelopedfromthehigh-compressionratio.
i. Dieselandpetrolenginescompressionstroke:

10. Agriculturalmachinerysection(daelp)
ii. Powerregulationindieselandpetrolengines:

11. Agriculturalmachinerysection(daelp)
iii. Dieselandpetrolenginesintakestrokes:
iv. DieselandPetrolEngineStrokes
IntakeStroke:

12. Agriculturalmachinerysection(daelp)
Thepistonisattopdeadcenteratthebeginningoftheintakestrokeandasthe
pistonmovesdownward,theintakevalveopens.Thedownwardmovementof
thepistondrawsairintothecylinderandasthepistonreachesbottom dead
centertheintakevalvecloses.
CompressionStroke:
Thepistonisatbottom deadcenteratthebeginningofthecompressionstroke
andasthepistonmovesupwardtheaircompresses.Asthepistonreachestop
deadcenterthecompressionstrokeends.
PowerStroke:
Thepistonbeginsthepowerstrokeattopdeadcenter.Theairiscompressedto
asmuchas500psiandatacompressedtemperatureofapproximately1000°F.
Atthispoint,fuelisinjectedintothecombustionchamberandisignitedbythe
heatofthecompression.Thisbeginsthepowerstroke.Theexpandingforceof
the burning gases pushes the piston downward providing powerto the
crankshaft.Thedieselfuelwillcontinuetobum throughtheentirepowerstroke
(amorecompleteburningofthefuel).Thepetrolenginehasapowerstrokewith
rapidcombustioninthebeginningbutlittletonocombustionattheend.
ExhaustStroke:
Asthepistonreachesbottom deadcenteronthepowerstroke,thepowerstroke
endsandtheexhauststrokebegins.Theexhaustvalveopensandasthepiston
risestowardstopdeadcenter,theburntgasesarepushedoutthroughthe
exhaustport.Asthepistonreachestopdeadcenter,theexhaustvalvecloses
andtheintakevalveopens.Theengineisnowreadytobeginanotheroperating
cycle.
B:Tractorenginesystems

13. Agriculturalmachinerysection(daelp)
1.Fuelsystem
AcompletefuelsystemforaSIengineconsistsof:
• Fueltank
• Fuelpump
• Fuelfilter
• Aircleaner
• Carburetor/fuelinjectionsystem
• Inductionmanifold
• Supplyandreturnpipes
2.Coolingsystem
Thebasicpartsofawatercoolingsystemare:
 Waterpump
 Radiator
 Fan
 Thermostat
 RubberHoses

14. Agriculturalmachinerysection(daelp)
3.Lubricationsystem
Systemparts
 Oil
 Oilpan
 Oilpump
 Oilfilter

15. Agriculturalmachinerysection(daelp)
 Oilgalleries

16. Agriculturalmachinerysection(daelp)
4.Electricalsystem
Startingandchargingsystems
Startingsystemparts
 Battery
 Keyswitch
 Solenoid
 Startingmotor
 Piniongear
 Flywheelringgear
Chargingsystemparts
 Alternator
 Voltageregulator
 Battery
 Rectifer

17. Agriculturalmachinerysection(daelp)
4:DAILY,WEEKLY,MONTHLYANDROUTINEMAINTENANCE
Thetractorplaysasignificantroleinmechanizedagriculture.Tokeepitworkingfora
longtimeataminimum cost,itrequiresanadequateandtimelymaintenance.Readthe
maintenancemanualgivenbythetractormanufacturerandfollow theprocedures
mentioned.
Daily/Everyday(After8-10hoursofwork)
1.Checkthelevelofoilintheengine.Itshouldbedone15minutesaftertheenginehas
cooleddown.Iffounddeficient,thelevelshouldbereplenishedwithengineoilofthe
rightgrade.
2.Checkthewateroftheradiatorandrefillit.
Regulator/r
Engine
Battery
Alternator
Starter

18. Agriculturalmachinerysection(daelp)
3.Cleantheaircleanerandchecktheoillevel.Ifitisless,fillittotherequiredlevel.Fill
cleanoilincasetheexistingoilhasbecomedirty.
Weekly(After50-60hoursofwork)
1.Repeatthedailymaintenancemeasure.
2.Checktheairpressureinthetyres.Ifthepressureislow,getthenecessaryair.
3.Checktheelasticityofthefan-beltunderthepressureofthethumb.Itshouldstretch
toadegreeof12&18mili-meters.
4.Cleantheairpressureandfillitwithanoiloftherightgrade.
5.Thewaterstoredintheoilfiltershouldbedrainedoutbythedrainplug.
6.Checkthewater-levelofthebattery.Ifwaterisfoundbelowthelimit,fillitwith
distilledwater.
7.Checktheleveloftheoilinthegearbox.
8.Applygreasetotheclutchshaftandbearings,brakecontrol,bearingofthefan,hubof
thefrontwheel,tierodandtheradiouscross,etc.
Afterafortnight(120to125hoursofwork)
1.Repeattheweeklyscheduleofmaintenance.
2.ApplyoiltotheDynamoandthestarter.
3.Cleanthecarboninthesmoke-tube.
4.Changetheengineoil.Todoso,keepthetractorinstartingpositionforawhileand
thenswitchitoffsoastoheatuptheentireoil,thendrainouttheoilthroughthedrain
plugandfillfreshandcleanoiloftherightgrade.
5.Incasetheoilfilterismadeofpaper,element,cloth,felt,etc.changethem.Cleanthe
metallicoilfilter.
6.Checkthefreeplayofclutchandbrake;itshouldbe15mmlong.Adjustitaccording

19. Agriculturalmachinerysection(daelp)
totheneed.
Monthly(After250hoursofwork)
1.Repeateverystepoffortnightlymaintenance.
2.Ifitisadvisedtocleantheprimarydieselfilter,(inthemanualsuppliedwiththe
tractor)cleanitorchangeit.
3.Washthefiltersofthetapoftheoil-tank.
4.Checkthewaterinthebattery.Ifitsrelativedensityisbelowthemark,changethe
battery.
Aftertwomonths(500hoursofwork)
1.Followthemonthlyscheduleofmaintenance.
2.Changetheotherelementofdieselfilter.
3.Gettheinjectoranddieselpumpcheckedeitherbyanauthorizeddealeroran
experiencedmechanic.
4.Contactyourauthorizeddealeroranexperiencedmechanicfortheinspectionof
valve.
5.Getthedynamoandtheselfstarterinspected.
6.Opentheoiltankandcleanit.
Afterfourmonths(100-1200hoursofwork)
1.Followthebi-monthlymaintenanceschedule.
2.Drainouttheoilofthegearboxandfillitwithacleanoiloftherightgrade.
3.Drainouttheoiloftheback-axleandfillcleanoil.
4.ChangetheoiloftheBelt-pulley.
5.CleanthefilteroftheHydraulicpump.
6.Changethesteeringoil.

20. Agriculturalmachinerysection(daelp)
7.Changethegreaseofthefrontwheel.
5:TRACTORDRIVINGANDHITCHING
 Drivingexercise
 Hitching
o Singlepointmount
o Twopointmount
o Threepointmount
6:MODEOFASSESSMENT:
Writtentest 60%
Oraltest 40%
Totalmarks 100%