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INTRODUCTION

The country, India, is basically an agricultural country where more than 65 %

of population enough food has to be produced. This cannot be produced with our

conventional bullock drawn implements. So there was need felt to invent such

machine which speeds up the agricultural production. Due to this reason the tractor

was invented.

Before we start, it is necessary to know how the word ‘tractor’ is derived. Prior

to 1900, the machine i. e. tractor is known as traction machine (pulling machine).

After 1900, both the words joined by taking ‘tract’ from traction and ‘tor’ from motor

calling ‘tractor’. The tractor is the machine which is used for applying high traction.

In our country, tractors were started manufacturing in real sense after

independence and at present, we are self-sufficient in meeting demand of country’s

requirements for tractors. At present in India, there are different tractor producing

factories present like Hindustan machine tools, Punjab tractors, Kirloskar tractors,

etc. is directly or indirectly connected to agriculture. Moreover for increasing

.

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COMPANY PROFILE

BIRTH OF HMT

In 1949 the idea of public sector tools was commissioned to be a corner stone

for the government’s industrial development plans. This led to the birth of

HINDUSTAN MACHINE TOOLS at Bangalore in 1953 which started a single

machine tools factory to produce lathes at Bangalore, in collaboration with M/s

Oerlikon of Switzerland.

Next, the company widened its product range beyond lathes by entering into

technical collaboration with other international leaders in machine tools such as Fritz

Werner, Herman Kolb, Errantly Somua, Gildermeister, Liebherr etc.

The second machine tool unit was set up in Bangalore in 1961 making use of

the Company’s own resources. The company diversified itself when, in collaboration

with Citizen Watch Company of Japan, the first watch factory was setup in Bangalore

in 1962 to produce hand watches.

The third machine tool unit was set up in 1963 at Pinjore, Haryana to produce

milling machines. In next few years, Machine Tool Units were set up at Kalamessary

in Kerala and in Hyderabad. The Printing Machinery division was attached to

machine tools factory at Kalamessary to qualities Printing Machine.

HMT’s tractor business commenced its operations in 1971 in technical

collaboration with M/s MOTOKOV, Czechoslovakia because of the priority given to

the agriculture in the national development plan and to take advantage of the green

revolution. HMT started the operations with the manufacturing of 25 Hp tractors.

Over the years, it has developed tractors ranging from 25 – 75 Hp.

The unit in Hyderabad began to make lamps and lamp making machines in

1973 to cater to the growing needs of rural. This was followed by producing

automatic watches.

A third watches factory was established in Srinagar to manufacture hand

wound watches for men. In 1975, the company took over the machine tool

corporation of India’s unit in Ajmer, Rajasthan and its name was changed to HMT

Limited.

In 1975, a separate international scales network called HMT was set up

comprising of company’s own agencies as well as other sales agents in Australia,

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Europe and America. This network was to handle the marketing strategy and

operations of the company overseas and it also extended its services to the other

leading Indians and overseas engineering companies. Since then this international

arm of the company has set up the turkey project in Algeria, Indonesia, Iraq, Kenya,

Nigeria and Srilanka.

HMT’S PRODUCTS

HMT PRODUCTS

The main products produced by HMT ltd are –

Machine tools,

Watches,

Tractors,

Bearings,

Printing Machinery,

Die Casting Machinery.

The divisions of HMT are described below –

BANGALORE

It produces lathes (both CNC and Non CNC), milling/ machining centers,

grinding machines, gear cutting machineries, simple drilling machines, special

purpose machines, die casting and plastic injection moulding.

It also produces refurbishing and retrofitting like heavy duty, turret lathe, multi

spindle drilling machines and fine boring machines.

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The other application components include the jigs, fixtures, some radar and

transonic components. It also develops hinomerik control system, Hyderabad.

CNC MACHINE

HYDERABAD

It produces the machining centers, CNC, Boring machines, milling machines,

die and mould machining centers, presses and brakes. It also produces special

purpose machines like CNC tube chamfering machines, cam shaft milling machines,

filament winding machines, horizontal and vertical coil winding machines, multi

spindle machining centers.

KALAMESSARY

It produces CNC lathes and printing machineries.

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AJMER

It produces grinders and lathes. It also manufactures some application

components like hydraulic lift mechanism for tractors, valve devices and oil priming

pump.

CNC MACHINE

After establishing two machine factories and a watch factory in Bangalore, the

Pinjore unit was established as the third machine tool factory. Breaking the ground

on 2nd may, 1962, this factory

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TRAINING CENTRE

In training centre, the basic machines are studied such as Lathe Machine,

Milling machine, Drilling Machine, etc.

STRUCTURE OF TRAINING CENTRE

TURNING SECTION

In turning section, we have learnt about the lathe machine which is mother of

all machines and play a basic role in mechanical line.

LATHE MACHINE

Lathe is probably the oldest machine tools. The basic idea about turning or

lathe machine came out in 17 century. Until 1770, lathes were useless metal cutting

because they lacked power and holding device, were not strong enough and

accurate enough to guide the tools. For its development to the form in which we

know it now, we owe much to Henry Muldsley, who developed the sliding carriage

and in 1880 built a screw cutting lathe.

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TRAINING CENTRE

TURNING SECTION

FITTING SECTION

MILLING SECTION

TRACTOR TRAINING SECTION

LATHE MACHINE

CLASSIFICATION OF LATHE MACHINE

1. Engine Lathe,

2. Speed Lathe,

3. Turret Lathe,

4. Toll Room Lathe,

5. Hollow Spindle Lathe,

6. Capstan Lathe,

7. Bench Lathe.

Lathe is also called Complete Machine. This single machine can do number of

operation.

FACING

This operation is carried out to produce flat surface at the end of part, which is

useful for parts that are attached to other components, or face grooving to produce

grooves for O-ring seals.

DRILLING

In this process a drilling of desire diameter is held in the tail stock and the

operation of drill is carried out.

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BORING

In this enlargement of hole or cylinder cavity made by previous process is

done. It improves accuracy and surface finish.

THREADING

In this operation internal and external threads on the surface are prepared.

KNURLING

In this operation a regularly shaped roughness is prepared on the cylindrical

surface for fascinating easy gripping.

FITTING SECTION

Fitting work is very important work in engineering. In fitting shop unwanted

material is removed with the help of hand tools. It is done for mating, repair and

manufacturing purpose. The person working in fitting shop is called as fitter.

Commonly used tools are hacksaw, files, chisels etc.

TOOLS USED IN FITTING SHOP

1. Clamping Tools

2. Measuring and Marking Tools

3. Cutting Tools

4. Striking Tools

5. Drilling Tools

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MILLING SECTION

Milling machine were basically developed to machine flat surface. But, the

present machine can machine flat, countered and helical surfaces, cut gears and do

various other jobs. Due to this all milling machine is one of the most useful and

necessary machine tools found in the shop and it rank next to the lathe in

importance.

Milling machine are designed to hold and rotate milling cutter or cutters, hold

the work piece and feed the work piece to the milling cutter in one several directions.

MILLING MACHINE

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FOUNDRY MECHANISMS

Since there are certain basic steps in the metal casting process, these may be

used as unit of mechanism.

Processing steps which lead them to the mechanism are:

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FOUNDRY MECHANISM

SAND PREPARATION

CORE MAKING

MOULDING,POURING AND SHAKEOUTS

MELTING

CLEANING

PARTS OF FOUNDRY SHOP

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FOUNDRY SHOP

SAND PLANT SYSTEM

SAND HANDLING

SYSTEM

CORE MAKING AND BAKING

SYSTEM

MOULDING MAKING AND

HANDLING

CORE SETTING SYSTEM

MELTING SYSTEM

METAL POURING SYSTEM

TESTING LAB

FETTLING SECTION

PAINTING AND PRINTING

SAND PLANT SYSTEM

The main objective of it is to reuse the used lad to the installation of sand

plant system. The vital task of sand plant system is to deliver well prepared sand at

required place that will determine the efficient working of the foundry. After casing

are knocked out of moulding box on a vibratory shakeout box that the used sand is

returned to the fixed amount of new sand, binders, catalysts and hardeners to get to

the required composition of the sand. Green sand, dry sand and oil sand are being

prepared in the sand plant. These constitutes are added in Muller in which all

contents are mixed thoroughly and then supplied via belt conveyor system to

working stations.

GREEN SAND COMPOSITION

Muller batch capacity 700 kg

New sand 35 kg (5%)

Bentonite 660 kg (94.4%)

Water 3.6 kg (0.4 %)

Return sand 1.4 kg (0.2%)

DRY SAND COMPOSITION

Return sand 80%

New sand 10%

Bentonite 1.2%

Dextrin 1.8%

Moisture 7%

COMPOSITION OF OIL SAND (100 KG OF SAND)

Bentonite 12 kg

Dextrin 25 kg

Linseed oil 15 kg

Moisture 20 G

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SAND HANDLING SYSTEM

For handling the sand i. e. move it from one place to another, the bucket

elevator and belt conveyor are used.

BUCKET ELEVATOR

When sand is to be conveyed vertically upward, a bucket is ideal. There are

two pulleys, one at the top and other at the bottom which carry an endless belt. The

belt carries number of buckets all around and the whole assembly is enclosed in

steel casting which has two openings, one at bottom for feeding and other at top for

discharge.

BELT CONVEYOR

It is used for transferring sand from one place to another. It consist of endless

belt, two pulleys or idlers for carrying a loaded belt and returning the empty belt, a

belt tightening mechanism and the belt cleaner. The angle of inclination should not

be exceeding 150 for dry sand.

CORE MAKING AND BAKING SYSTEM

As patterns are made to get to outer shape of the casting, the inner shapes

are used to for whole generation core placed in the moulds. As the core comes in

contact of molten metal that must possess following characteristics:

1. Core sand must have high strength to bear the pressure of metal when

poured.

2. The sand must have high refractory characteristics so that it may not fuse due

to high temperature being in contact with molten metal.

3. It must have high cohesive property so as to get good finish castings.

Zircon paint (alcohol base) dried just by lightning it up. Large and heavy cores

are baked along with the dry sand moulds in oven.

Core drying cycles for oven:

3000 C – 1 12

hrs.

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2000 C - 212

hrs.

Cooling time in oven 3 hrs.

After baking, the hardness is tested by using hardness meter

CORE MAKING

MOULD MAKING SECTION

Moulds are being made on moulding machine pedantically powered rammers.

Metallic patterns are being used. After mould being made on moulding machine, it

goes to sand cutter which removes extra sand present and level the mould base,

from on to the power operated roller conveyor, the mould is handled using the swing

type crane. Core setting is done in drag part of mould. Zircon painting is sprayed on

to the mould (as paint is alcohol based hence get dry up by lighting fire.

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MOULD MAKING

MOULD BAKING

Dry sand moulds are to bake to acquire hardness to with sand the pressure

produced by the flow of molten metal. These are baked in ovens. Mould baking

cycles for ovens 300C for 212

hrs. and Cooling time in oven 3 hrs.

MELTING SECTION

It is having two types of furnace.

1. Electric induction furnace,

2. Copula furnace.

FETTLING

After they are knocked out on vibrator shake, the casting head to be finished

by the removal of projections whether they are gets riser or runner that where there

as a part of design aspect or the projection which has appeared as a defect like fins

or blow holes. The process that involves all these procedure of casting finish is

termed as fettling.

Fettling operation is divided into following stages:

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1. Knocking out of dry sand cores,

2. Removal of gates and risers,

3. Extraction of fins and other projections,

4. Cleaning and smoothing of the surface,

5. Repair casting by filling of the blow holes, straightening the wrap or deformed

casting.

PRIMING AND PAINTING

After all the cleaning process has been performed then the final step is

priming and the painting casting. The machine tool castings are generally big and

are handled with crane during painting. Painting is done by brushes only.

MELTED METAL

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HEAVY MACHINE SHOP

INTRODUCTION

In heavy machine shop all the heavy part of tractor are machined like gear

box housing, Main transmission housing, Front cover etc. all the parts undergoes

different operations like milling, boring, drilling, tapping, slotting etc. in HMS section.

The entire machines in this section are special purpose machine; it means the

machine doing special or specific operation on a job.

The advantage of special purpose machine is that it increases the rate of

production. The machines are capable of machining any number of identical parts in

a very less time.

PARTS MACHINED IN HMS

1. Gear box housing

2. Main transmission housing

GEAR BOX HOUSING

Gear box housing is used for fitment of gears and shafts. The material used

for Gear box housing is cast iron.

GEAR BOX HOUSING

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PROCESS OF MANUFACTURING OF GEAR BOX HOUSING

OPERATION

MARKING THE GEAR BOX HOUSING

With help of crane, we put the housing on the surface plate and after this with the

help of vernier height gigue we mark the gear box housing. Marking is done of the

gearbox is done for remove the all allowances material.

BOTTOM MILLING

With help of crane we put the work piece on the milling machine (SPM). Bottom

milling is done for removing the extra material on the gear box housing.

DRILL THE LOCATION HOLE ON THE GEAR BOX HOUSING Location

holes are made for fix the housing on the different machine.

TOP MILLING

Put the housing on milling machine according to location holes. Top milling done for

removing the extra material on the housing.

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MARKING THE GEAR BOX HOUSING

BOTTOM MILLING

DRILL THE LOCATION

HOLE

TOP MILLING FRONT AND REAR COVER

LEFT AND RIGHT MILLING

SLOT MILLING

BORINGPRE BORING OF STEERING

BORE

HEAVYY DUTY DRILLING

BOTTOM MILLING HOUSING

TAPPING DRILLING FOR CLUTCH

FINAL BORE

WASHING

INSPECTION

FRONT AND REAR COVER

According to their location of hole we fix the work piece on the milling machine. For

removing the all allowance on to the housing.

LEFT AND RIGHT MILLING

For removing the all allowance on to the housing.

SLOT MILLING

In this milling we made the slots for gear forks which used for change the gears.

Dimension of slot is 16mm.

BORING

Boring is done for removing extra material from bores to make the bore according to

their dimensions.

PRE BORING OF STEERING BORE

Pre boring is done for removing the allowance from steering bore.

HEAVY DUTY DRILLING

It is done for making the drilling in to the housing for joining purpose.

BOTTOM MILLING HOUSING

20 drills simultaneous.

TAPPING

Tapping is for making the internal thread in to the drilled holes and for joining

purpose.

DRILL FOR CLUTCH AND PEDAL

For joining the clutch and pedal drilling is done on both faces right and left on the

gear box housing.

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FINAL BORES ON THE ALL BORES

steering bore, reverse gear and shaft boring on the boring machine.

WASHING

Washing the gear box housing.

INSPECTION

Inspect the housing for defect like blow hole or others.

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MAIN TRANSMISSION HOUSING

Main Transmission Housing is manufacturing in heavy machine shop. M.T.

Housing is used for setup the differential and axle assembly. Material used for M.T

Housing is cast iron.

MAIN TRANSMISSION HOUSING

MANUFACTURING PROCEDURE OF M.T HOUSING

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MARKING M.T

HOUSING

HORIZONTAL MILLING.

RADIAL DRILLING

HORIZONTAL MILLING

BORING

MILLING BORING FINISH

WASHING

INSPECTION

MARKING M.T HOUSING

With help of crane we put the housing on the surface plate and after this with the

help of vernier height gauge we mark the M.T. Housing according to their

dimension. White paint is used foe marking.

HORIZONTAL MILLING.

Horizontal milling is done for removing the extra material or allowances according to

their drawing

RADIAL DRILLING

Radial drills are used for the made the location holes in the housing and these

locations are used for seat the job on the different type of machine.

MILLING OF M.T. HOUSING

In this operation milling of four faces is done front, rear, left and right. In operation

we fix the job on their location and holes and after we do milling.

BORING

In this boring operation we do rough boring of front, left & right bores.

Dimensions of bores:

Left hand bore: 290mm.

Right hand bore: 288& front hand bore: 90mm

HORIZONTAL MILLING ON FRONT

Horizontal milling is done for remove the extra material or allowances according to

their drawing. Horizontal milling is done on SPM milling machine.

BORING FINISH

After horizontal milling we put the housing on the boring machine on their location

holes. it is done for finishing purpose.

WASHING

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Washing is done to remove chips and oil. this is done after all the operation.

INSPECTION

Inspection of work piece according to their drawing.

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LIGHT MACHINE SHOP

INTRODUCTION

As the name suggests that in this section light parts or small parts of tractors

are machined such as speed gears of tractor, sun & planet gears crown wheel, PTO

shaft, clutch shaft, spline shaft, front and rear axle.

SPLINE SHAFT

A shaft with longitudinal gear like ridges along its interior or exterior surface

is called spline shaft. the function of spline shaft is to transmit the power from

flywheel to lay shaft. Material used for spline shaft is low carbon steel.

SPLINE SHAFT

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PROCESS FOR MANUFACTURING OF SPLINE SHAFT

After these process spline shaft send to heat treatment plant for hardening

process.

1. Gas carburizing & hardening.

2. Tempering

3. Shot blasting.

4. Straightening.

5. Centre grinding.

6. Internal grinding.

7. Fitting.

8. Inspection

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RAW MATERIAL

CUTTING OF SHAFT

FACING AND CENTERING

CNC TURNING

INSPECTION

GEAR HOBBING.

GEAR TOOTH

ROUNDINGFITTING.

WASHING. INSPECTION GEAR SHAVING.

BENCH DRILLING

BEVEL PINION SHAFT

Bevel pinion shaft is used for transmit the power from gear box to differential.

The material used for it is low carbon steel.

BEVEL PINION SHAFT

PROCEDURE OF MANUFACTURING OF BEVEL PINION SHAFT

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RAW MATERIAL

MATERIAL CUTTING

FACING

TURNING

INSPECTION

GEAR HOBBING

FITTING

WASHING

GAS CARBURIZI

NG

ANNEALING TURNING

CYLINDRICAL GRINDING

THREAD ROLLING

DRILLING

TEMPERING SHOT BLASTING

STRAIGHTENING

WASHING & INSPECTION

WHEEL SHAFT

Wheel shaft is assembled in axle housing and its transmit torque to wheels.

WHEEL SHAFT

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MANUFACTURING PROCEDURE OF WHEEL SHAFT

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RAW MATERIAL

FACING DRILLING

RADIAL DRILLING

GEAR HOBBING

INSPECTION

INDUCTION HARDENING

TEMPERING

CYLINDRICAL GRINDING

THREADING

FITTING

HORIZONTAL MILLING

FITTING

INSPECTION

HEAT TREATMENT

All components (manufactured in LMS) after undergoing machining operation

are subjected to heat treatment. It is done so as to improve hardness and strength of

these components viz. gears and shafts.

Basic operations performed during heat treatment:

1. Hardening,

2. Quenching,

3. Annealing,

4. Tempering,

5. Normalizing,

6. Carburizing.

Melting temprature: 6400C,

Carburizing media 13- 15 % sodium cyanide + 85 % BaCl + NaCl

HARDENING

For medium carbon steel and high carbon steel 8400C- 8500C

For other 770 – 8200C

Hardening is performed on the various metals and its alloys to provide them

with strength and wear resistance. It is accomplished by heating the component

above its hardening temperature and quenching it in water.

HEAT TREATMENT PROCESS

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SHAFT HARDENING

QUENCHING

Emercing hot metal in desired water or oil does quenching. Here transfer of

heat is ensured at slow rate so as to remove internal stresses to permissible limit.

QUENCHING MACHINE

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QUENCHING FURNACE

NORMALIZING

In this process, iron alloy casting is heated to 50 – 600C above critical

temperature range. The casting is held for definite time and then allowed to cool in

still air. Normalization eliminates casting or cooling strains and resultant casting is

easy to machine.

CARBURIZING

Process of adding carbon to surface layer of the component is called

carburizing. It is the process of casehardening, which is addition of some elements

like carbon, nitrogen to the surface by diffusion for surrounding medium at high

temperature the purpose of carburizing is to obtain high surface wear resistance and

obtain a hard surface.

TEMPERING

For medium carbon steel and high carbon steel 6700 - 6800 C

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for fasteners tempering to be done at 3500 – 4000 C for 1 – 2 hrs.

In tempering long grains formed during quenching are broken into smaller

grains so as to improve elasticity of the material. Here heating is done at around

1800 - 2000 C for around 2 hrs. and then cool in air. It reduces internal stress and

stabilizes the structure of metal.

ANNEALING

For medium carbon steel and high carbon steel 6800 – 6900 C.

CASE HARDENING

Carburizing + hardening.

PROCESS USED FOR BLACKENING

1. Job is clean with cotton waste.

2. Put the job in the NaOH solution for 10 to 20 min. for de-greasing or

decomposition.

3. Wash it with warm water.

4. De-rust the job in the rust solution.

5. Wash it with water.

6. Shift it to blackening furnace at 1200 C for 10 – 20 min. according to sectional

area

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HEAT TREATMENT FURNACE

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ENGINE ASSEMBLY

CRANKSHAFT FITTING

First of all bush type liners are inserted into the bearing holes. The liner is

provided with recess to store a minimum amount of oil, which wets as the crankshaft

during storing engine. The bearing cap is opened and crankshaft assembly is placed

into it. The bearing cap is tightened again with 10-12 kg-m torque rod and crankshaft

is checked that it is revolving easily or not

CRANK SHAFT

TIMING GEAR FITTING

The idle shaft is pushed into the crankcase and roller type bearing with lock is

inserted into the shaft. The idle timing gear is then pressed into the bearing. The

timing gear is punched at two places and punched sigh has to be matched with

punched mark of {on} crankshaft.

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TIMING GEARS

PISTON ASSEMBLY FITTING The piston assembly is fitted into the liner and the big end is tightened to

crankshaft line is fitted with piston assembly. The grade mark is towards the

camshaft. The piston ring cuts should be so adjusted that there should not be in

same line.

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ASSEMBLY OF PISTON AND CONNECTING ROD WITH CRANK SHAFT

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LUBRICATION OIL PUMP MOUNTING

The lubrication oil pumps connected to crankshaft gear by an idle gear of 2-3

degree. The crankshaft and pump gear has 22 teeth each. The pump is provided

with relief valve through which it opens at 4kgf.

In the case of are loading or something injected in the main gallery then pressure is

released from their valves.

LUBRICATION OIL PUMP PARTS

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REAR COVER AND FRONT COVER MOUNTING The rear cover and front cover are cleaned perfectly with air and filled to engine

with seals in between mounted

FRONT END COVER REAR END COVER

CAM SHAFT FITTING The camshaft is inserted into the camshaft hole with bearing and bolt ends are

locked by circle. The camshaft is forged from alloy steel or cast iron and is case

hardened. The one end of the camshaft is provided with gear, which is locked, gear

z-50 for exact timing of the camshaft gear mark is matched with the mark on idle

gear. Another gear pump is attached with idle gear, which serves the purpose of

driving the fuel injection pump.

CAM SHAFT

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FLYWHEEL MOUNTING The flywheel is mounted on the crankshaft and bolts are tightened with 11-12

kg-m force. The F.I.P is connected to F.I.P gear through F.I.P shaft

The F.I.P drive shaft is specifically designed to advance the time of injection.

The both ends of F.I.P drive shaft is provided with spline, One side a key is provided

which is locked to timing gear and recess on their side is pushed into F.I.P slots. The

angle between the key and recess of 18 degree thus the fuel injection is advanced

by 18 degree.

FLYWHEEL

SETTING OF FUEL INJECTION PUMP WITH RESPECT TO

CRANKSHAFT

This timing is set by setting the flywheel i.e. crankshaft angle into particular

designed value by using following procedure:-

1. First of all, supply of fuel injection pump is disconnected from the 1st cylinder.

2. Rotate the flywheel to make the piston executing compression stroke in the

same cylinder.

3. Then a flask containing fuel, is placed at a level higher above the pump and

inlet to pump is connected to the flask by a pipe. This arrangement provides

inflow of fuel to the F.I. pump.

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4. Outlet of F.I. pump is connected to a small pipe to collect the fuel.

5. Now the flywheel is rotated so that piston moves towards the TDC. As we

know when piston moves towards the TDC, the plunger in the F.I pump

covers the spill port and fuel starts flowing out through the outlet pipe.

6. Now the flywheel is brought to the marked position according to design and

then the F.I. pump is tilted, keeping its input shaft fixed so that fuel starts

flowing out.

7. Now the FI pump is fastened on the same position.

CYLINDER HEAD MOUNTING

The cylinder head assembly is placed on the piston and studs are passed

through it. If the height of the piston at TDC from the surface is more then 0.1 mm

than the gasket of given thickness are used. If it is 0.1 to 0.5 mm then 1.2mm thick

gasket is used. If it is 0.5 to 0.8mm then 1.5mm thick gasket is used. The cylinder

nuts are tightened by 17-18 kg-m forces.

WATER BODY AND PULLEY MOUNTING

The water body is mounted with thermostat control valve opens at 70 degree

Celsius. The pulley is mounted on camshaft.

The assembly is removed from the trolley, is placed on the stationary frame.

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FUEL INJECTION PUMP MOUNTING AND SETTING OF FUEL

INJECTION PUMP

The gear of F.I.P is first of all meshed with F.I.P drive shaft and is loosely

tightened to set the timing of gear first of all pointer is tightened on the crankcase

and flywheel us rotated which is meshed for 16, 18, 20, 24 angles. The pointer is set

at 18 of flywheel and then pump is rotated clockwise till one from first nozzle stop out

blowing. At this position a cut mark is made on both the pump and crankcase for

further setting. The pump is tightened properly and pipes are tightened over nozzle

and injectors. The head of position is covered with covers and the complete engines

are sending to engine testing shop. The whole of engine shop is air-cooled.

FUEL INJECTION PUMP

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ENGINE TESTING

INTRODUCTION

Engine testing is done for checking the performance of newly assembled

engine to find out any assembly fault, their HP, leakage and other fault. Engine

testing shop of standard is equipped with latest digital control equipment. The engine

testing is done with the help of turbine (water) or hydro dynamometer is four in

number so that four engines are tested at one time. The shop is equipped with heavy

duty oil filter, which is used to clean the oil from dust or other large particles the shop

has bush pump tester is measured on the based of S.A.E rating. The society of

automobile engineer’s USA has specified die method of measuring the power output

of the engine for standardized purpose. The engine is run without generator.

TRACTOR TESTING

Tractor testing is done under the international organization for standardization

(ISO). The first tractor with an internal combustion engine was introduced in

American agriculture in the year 1889. The tractor testing act was passed in U.S.A in

1920. In India tractor testing station was finally establish at Budani in 1959 for tractor

testing atmospheric pressure shall not be less than 96.6 Kpa. The basic task is

design and development of engines is to reduce the cost and improve the efficiency

and the power output. In order to achieve the above task the development engineer

has to compare the developed engine with the other engines in terms of its output

and efficiency. Towards the end, engineer has to test the engine and make

measurements of relevant parameters that reflect the performance of the engine

ENGINE TESTING AT STANDARD TRACTORS, PURPOSE OF TESTING A TRACTOR ENGINE

In general purpose of testing an I.C engine is to determine the following:

1. To determine the rated power output with respect to the fuel combustion

in kg per kw hr brake power output

2. To determine the mechanical and thermal efficiencies of the engine

3. To see the performance of the engine at different loads

4. To determine the quality of lubricating oil required per B.P.Kw-hr.

Page | 42

5. To determine the quality of cooling water required per B.P.Kw-hr.

6. To determine the overload carrying capacity of the engine

7. To prepare the heat balance sheet of the engine

SOME IMPORTANT TERMS AS ISI STANDARAD TERMINOLOGY

SPEED

The speed of a engine is the mean speed of its crankshaft in R.P.M expect in

the case of free piston engines where the speed is the number of cycles per minute

of the reciprocating components.

STEADY LOAD SPEED BAND

It is the maximum total variation in speed expressed as a percentage of the

mean speed, which may occur while there is no change in the external load

conditions

CONTINUOUS POWER

The power which engine is capable of delivering continuously between the

normal maintenance intervals stated by the manufacturer at the stated speed and

under stated operating conditions

INDICATED POWER

It is the total power developed in the working cylinder by the gases on the

combustion side of the working pistons

FRICTION POWER

It is the power consumed in friction resistance

BRAKE POWER

It is the total power consumed in friction resistance

Page | 43

FUEL CONSUMPTION

It is the quantity of fuel consumed per unit power per unit of time. It is general

expressed in grams of fuel consumed per B.H.P.

MECHANICAL EFFICIENCY

It is defined as the ratio of the power obtained at crankshaft i.e. brake power to

the indicated power.

Thus mechanical efficiency = brake power (B.P.) / indicated power (I.P)

THERMAL EFFICIENCY

INDICATED THERMAL EFFICIENCY

It may be defined as the ratio of heat converted into indicated work to the heat

energy supplied by the fuel, during a specified period of time.

So, indicated thermal efficiency

= heat equivalent to I.P per min. / heat supplied by fuel per min. =I.P.

*60 / Mf*CV

BRAKE THERMAL EFFICIENCY

It may be defined as the ratio of heat equivalent to brake power (B.P) to the heat

energy supplied by the fuel during a specified time

So brake efficiency

= heat equivalent to B.P per min. / heat supplied by fuel per min. =B.P. *60 /

Mf*CV

PREPARATION FOR TEST

Test runs shall be made on an engine as being offered to the consumers. Before

starting the engine tests, the engine shall have been thoroughly run in the fuel and

lubricating oil used during the test shall be specified by the engine manufacture

In general the engine operating temperatures and the lubricating oil pressure during

the test shall be maintained at the values recommended by the manufacturer

Page | 44

IN ENGINE TESTING WE NOTE DOWN THE FOLLOWING DATA

1. Revolution per minute (R.P.M.)

2. Fuel time

3. Engine Lub. Oil pressure

4. Water outlet temp.

5. Lubricating oil temp.6. Torque (N-M)7. Smoke reading with the help of bosch smoke meter8. In case of silencer a noise meter & u-tube manometer for measuring

backpressure

With the help of the data we calculate following parameters1. B.H.P = R.P.M *N-M / Dynamometer constant2. IN KILOWATTS = R.P.M *N-M / 9549.3053. Specific fuel consumption (S.F.C) = 297000 / B.H.P*fuel time

Page | 45

TRACTOR ASSEMBLY SHOP

INTRODUCTION Tractor assembly shop is main shop of Standard Tractor division. In this

shop, different machined parts, housing & other components, which are machined in

other shops or purchased from outside, are assembled.

Then sub assemblies like differential housing, gear box, rear cover and other

parts are sent to main assembly line. Then the tractors are sent to painting section.

TYPE OF PTO TRACTOR

1. Multi PTO Tractor

2. Ground PTO Tractor

3. Simple PTO tractor

MULTI PTO TRACTOR

In this type, speed of PTO shaft can be varied as there is an arrangement that

either it can be run from the output of gear box or from input to the gear box, which

provide it 6 speeds of PTO shaft in high speed mode as well as 6 in low speed

mode. However, there is provision that PTO can be run while tractor is not moving

i.e. wheels are in rest position.

GROUND PTO TRACTOR

The basic difference between this type and multi PTO shaft is that it provides

different speeds only when tractor is moving, while Multi PTO shaft can provide

different speeds even when tractor is in rest position.

It is particularly used when PTO is to drive thoster and reaper.

SIMPLE PTO TRACTOR In this type PTO can run only at one speed of 540 rpm, doesn’t matter whether

tractor is moving or not.

ASSEMBLY TAKES PLACE IN FOLLOWING PHASES

1. Differential housing assembly

2. Rear cover assembly

Page | 46

3. Gear box assembly

4. Main assembly line

5. Painting phase

DIFFERENTIAL HOUSING ASSEMBLY It is rear part of the tractor chassis. It is filled with CL-90 hydraulic fluid, which is

used for hydraulic purposes as well as lubricating differential components and gear

box components. PTO shaft is also passed through this housing. Various functions

performed in differential housing are as following:-

1. Differential turns the drive through 90˚ from gear box output shaft to bull gear

shafts which in turn drive rear wheels.

2. Very important function of differential is distribute the power at wheels

according to whether tractor is running straight or is turning towards left or

right.

3. Reduction of speed in two stages; 1st reduction at tail pinion and crown

wheel, 2nd at bull gear and bull pinion gear drive.

TRACTOR ASSEMBLY SHOP

Page | 47

MAIN PARTS OF DIFFERENTIAL HOUSING1. Crown wheel

2. Tail pinion

3. Cage assembly with sun and planet gears

4. PTO shaft

5. Bull pinion shafts; B.P. left & B.P. right

6. Bull gears

7. Bearings

8. Brakes housing assembly

9. Oil seals, Gaskets etc

ASSEMBLY OF CROWN WHEEL

1st of all, all components are washed with oil to remove dirty particles.

Cage has two holes. In these holes dowels are tight fitted for accurate fitting of

crown so that all holes of the cage & crown are in same line. The crown wheel is

pressed on cage with hydraulic press and tightened by bolts with lock washer,

and then the right bevel gear is placed on its cage seat. The four planet gears

are put on across the four arms of rigid member along with the washers. This

assembly is placed in the cage and then left bevel gear is placed. Operator

checks the motion of assembly by manual inspection.

CAGE ASSEMBLY

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TAIL PINION ASSEMBLY In tail pinion assembly, cone for tapered roller bearing is fitted with hydraulic press. The bearing is heated before the tight fit. Then tail pinion is inserted inside the bearing. Different no. of shims are used for preloading purposes and proper positioning of tail pinion. Whole assembly is tightened by nuts & bolts.

REAR AXLE ASSEMBLY

In rear axle assembly bolts are tight fitted in the holes of hub. Two

bearings on either side of the trumpet housing are tightened at gang drill.

BRAKE ASSEMBLY Standard tractors are provided with heavy self energizing water sealed disc

brakes with ventilation pipe, which gives better cooling. This ventilation results in

30% reduction in pad temp. Brake housing cover contains two discs made up of

asbestos base. The max temp resistance is about 300˚C. Below these discs there

are two cast iron disc plates (with steel balls), which are held by springs. Whenever

brake is applied, the CI plates rotate and due to presence of balls these plates

moves axially 7 press the brake pads against broke housing and differential housing.

As the brake pads are mounted on BP left & right, therefore above discussed

process results into braking action.

BRAKE ASSEMBLY

Page | 49

PTO SHAFT ASSEMBLY Firstly bearings are fitted on the supports of PTO shaft in the housing and then PTO shaft is inserted through the rear of the housing.

TESTS PERFORMED ON DIFFERENTIAL HOUSING

1. Backlash Testing

2. % age of Contact Test

3. Preloading Test

BACKLASH TESTING

This test is performed with the help of plunger dial gauge. Backlash in crown

wheel is not allowed more than 20 to30 micron. If it deviates from this value then

packing is changed on either side of cage in bearing housing. If it exceeds the 30

micron value then shims are removed from right side and shifted to left side. If it is

less than 20 micron then vice versa. Also run out for crown wheel is 0.5-1 mm.

%AGE OF CONTACT TEST & PATTERN TEST

This test is done with the help of yellow paint. It is applied on some of teeth of

crown wheels. Then it is made to rotate with the help of handle, then tail pinion

meshes with these teeth and meshing leaves impression on the yellow painted teeth.

This impression indicates the contact line on the teeth as well as the point where

contact is broken. The contact shouldn’t brake in a way such that contact doesn’t

follow through the complete tooth width. Proper adjustment can be made by

selecting suitable no. of shims used for fastening the tail pinion assembly on the

housing.

PATTERN TEST

Page | 50

The bull gears are tighten to trumpet housing assembly by lock nut and the whole

assembly is also tightened by nut and studs on the outer side of differential housing.

Then PTO shaft head cover is tightened to protect its outer teeth. The sliding gear

and PTO shifter rod assembly is mounted on differential housing. Two filters are

placed inside the differential housing and then whole assembly is sent to main line.

REAR COVER ASSEMBLY It is used to cover the differential housing. It contains lift control system, which I

hydraulically operated. Driver seat is fitted on the upper side of rear cover. The

Response Valve housing(R.V. housing), control valve, ram cylinder and other

components are fitted inside and outside the rear cover.

The main components of rear cover assembly are:-

1. Control valve assembly

2. R.V. assembly

3. Ram cylinder and piston assembly

4. Operating sector assembly

5. Sensors tube assembly

6. Gaskets, Bolts and Nuts

7. Other components

RAM CYLINDER ASSEMBLY It contains cylinder with piston inserted inside it. The relief valve assembly is

mounted at the top front of cylinder. The connecting rod is placed in piston rear side

and one side is locked with ram arm assembly. Then ram arm, spacer and seals are

placed. The ram arm is keyed to a shaft called rocker shaft. At the end of rock arm

assembly, lift arm assembly is placed and then looked with bolts on both sides.

R.V. ASSEMBLY

It contains one response valve, check valve and release valve. It is also

connected with control valve through pipe housing. The knob is placed on the top of

response valve to close or open the response valve as per requirements.

These days R.V housing and control valve are integrated into single unit.

Page | 51

CONTROL SECTOR ASSEMBLY

It contains the draft control assembly and position control assembly. Both these

assemblies are connected to their respective leavers. The positional control

assembly is connected to black marked leaver & draft control leaver is connected to

red marked leaver. In simple words, positional control leaver lower or up the lift

linkages, while draft control leaver change the sensitivity of sensor.

First of all, rear cover is mounted over the moving trolley and tightened with bolts.

Then operating sector assembly is placed at its respective place. A sensor tube is

placed at rear side of the rear cover. Earlier R.V. housing was used to fit outside the

rear cover which was connected to the control valve through piping in the rear cover

housing. But now these days both R.V. housing & control valve are integrated into

single piece and it is fitted inside the rear cover.

Control valve contains three valves i.e. back measure valve(3-6 kgf), unloading

valve and scroll valve. Oil from pump goes to R.V. through pipes, which is further

connected to the check valve through inner hole of R.V. housing and back pressure

valve of control valve. The operating pressure of check valve is 9-12 kgf and

operating pressure of back pr valve is 3-6 kgf. During un-operated position, the oil

flow continues through back pr valve of control valve.

During operation of position arm the unloading valve closes the gallery of oil to

the back pr valve. Thus the pressure in the R.V. housing builds up which opens the

check valve at 9-12 kgf. At this position, the oil goes in the ram cylinder, which

further operates the lift arm. For requirement of any position of lift, the knob of

response valve of RV housing is rotated which cut the supply of oil and position of

ram arm is achieved. Sensor tube works in the field during ploughing of soil with

harrow. When harrow deeply dug in soil, draft is set at position through sensor tube.

The rocker arm attached to sensor and harrow link, when push the sensor tube

inside and automatically controls oil supply.

GEAR BOX ASSEMBLY

INTRODUCTION

Gear box in the standard tractors is of sliding mesh type. It is the main assembly b/w

the engine and differential housing. Advantages of using constant mesh type gear

Page | 52

box are higher mechanical efficiencies and lower noise level due to use of helical

gears instead of straight spur gear.

It gives the tractor a top speed of 30 kmph and a minimum speed of 2 kmph. There are 5 forward and one reverse gears with a high and low level.

GEAR BOX PARTS

Page | 53

MAIN COMPONENTS OF GEAR BOX

1. Input shaft assembly

2. Output shaft assembly

3. Lay shaft assembly

4. Intermediate shaft assembly

5. Actuator shaft assembly

6. Gears

7. Gear box housing

8. Shifter rods

9. Shifter forks

10.Bearings

11.Fasteners, Gaskets and spacers

12.Planet gear and carrier assembly with internal gear

13.Clutch actuator (C.A.) assembly

TRANSMISSION GEARS

CLUTCH ACTUATOR

Clutch actuator assembly contains clutch actuator guide on which bearing is

tight fitted and locked with circlip.

Page | 54

LAY SHAFT ASSEMBLY

The lay shaft is hollow shaft with splines on the outer surface. One end of lay

shaft is threaded (in case of single clutch) and tightened from front side of gear box

with a hexagonal nut.

The whole assembly consists of gear Z-49 (i.e. constant mesh gear with input

shaft gear), spacer 15 mm, gear Z-42, gear Z-38, spacer 30 mm, gear Z-31, gear Z-

29 and a spacer 25 mm and bearing with a circlip.

In case of dual clutch tractor model, the drive shaft is placed through hollow

lay shaft. The drive shaft consists of splines at one end and a gear (Z-45) on the

other end.

The gears are constantly meshed with the gears on the intermediate shaft.

The main function of the lay shaft is to rotate the fixed gears on it from where we

can get different speeds with the help of sliding gear on the drive shaft.

INPUT SHAFT ASSEMBLY

Input shaft consists of helical gear on one end and splines on the other end.

Splined part is attached to clutch and gear is in constant mesh with Z-49 gear on the

lay shaft. Input shaft is put into gearbox with the bearing, which is locked by circlip.

OUTPUT SHAFT ASSEMBLY

Output shaft assembly consists of a solid shaft with the splines on the outer

surface. The shaft is placed into the bearings and locked by circlip. Some of the

back part of the shaft is projected outside the gear box to get drive from it. The

assembly of shaft consists of gears with no. of teeth 18, 22, 30, 32. The sliding gear

2 is used for 1st and reverse gear; sliding gear 30 is used for 2nd gear and sliding

gear 22 is used for 3rd gear; sliding gear 18 is used for 4th gear and it can be keyed

to the splines of the input shaft for the 5th gear.

ASSEMBLY OF GEAR BOX

First of all, the gear box is mounted over the trolley, which can be moved with

the help of chain conveyor system. The idler gear is placed with their idler gear shaft

in the gear box at its respective place.

Page | 55

Then lay shaft assembly is inserted into its respective holes and tightened

from front of gear box housing by a hexagonal nut. Z-19 gear of input shaft is in

constant mesh with Z-49 gear of lay shaft. Then output shaft assembly is placed into

the gearbox where its one end is supported over the needle bearing in the input

shaft and other one is supported in the gearbox housing.

For D.C. models, the intermediate shaft, which is hollow, is placed over the

input shaft, but both shafts are free with respect to each other. A gear Z-21 is keyed

to this shaft, which is meshed with a gear Z-43. This Z-43 gear is keyed to the shaft

which drives the PTO shaft. This particular shaft is passed through the hollow lay

shaft and supported on needle bearings in the lay shaft.

The four selector rods are placed in the holes with spring loaded ball for each

rod. The gear selector forks are inserted into the groove of sliding and then

tightened over the gear shifter rods with the help of bolts. Then another selector rod

is fitted, which protrude on the back side of gearbox. This rod actuate epicyclic gear

train of the high-low shifting assembly. Then the top of gear box is covered with its

top mating part and then fastened with the bolts.

Then the gear box is sent to the main assembly line.

PROCEDURE OF TRACTOR ASSEMBELY

GEAR BOX SUB ASSEMBLY

First gear box housing is put on the trolley and different type of the shaft and the

gear assemble in the gear box.

CLUTCH ASSEMBLY

Clutch is device used to connect and disconnect the tractor engine from the

transmission gears and the drive wheels. Clutch transmits power by mean of friction

between driving members and driven members. Generally dual clutch is used in the

HMT Tractors.

MT HOUSING ASSEMBLY

In this housing the differential unit and the hydraulic pump is fitted also it provide the

special arrangement of gears.

Page | 56

REAR AXLE MOUNTING

Mount brake shoes, brake shoes holder, expander unit, retractor spring wheel shaft

along with flange, tapered roller bearing, a bull gear along with spring and locked

device to prevent axial movement off bull gear, on the porter housing.

Assemble rear axle housing on the portal and then assemble the crown on the

differential shaft around the brake shoes.

LIFT MOUNTING

After mounting of axle on the differential lift is mounted on the main transmission

housing which is used for the load up to 1200 kg and 1400 kg.

ENGINE MOUNTING

After then engine is mounted on gear box and MT housing and portal assembly with

the help of bolts.

FRONT AXLE MOUNTING

Assembly front axle wheel hub, pivot, king pin, track record on the extension along

with locking devices, bush and bearings.

Connect these two extensions with each other by the extension tube.

STEERING ASSEMBLY

STEERING

The system governing the angular movement of front wheel of tractor is called

steering system. This system minimizes the efforts of the operator in turning the front

wheel with the application of leverages.

BRAKE SYSTEM ASSEMBLY

Brake is used to stop or slow down the motion of tractor. It is mounted on the driving

axle and operated by two independent pedals. Each pedal can be operated

independently to assist the turning of tractor during the field work or locked together

by means of a lock.

Page | 57

WASHING ZONE, DRYING OVEN AND PAINTING

After mounting all the parts on the body it sends to washing zone for remove the

unwanted material like dust and machining material.

After washing of the body, it sends to oven for drying the body where we dry

it. After drying the body painting is done on the body. Grey paint is used for painting

the body and the chassis.

GREASING ZONE

Greasing is done all the greasing points with the help of pneumatic gun.

The following are the grease points:

1. Front wheel hub

2. Front axle extension

3. Front axle pin

4. Clutch shaft

5. Right hand stud

6. Three point linkage

7. Tie rod end

Three free play of foot brake is maintained 2mm.

AIR CLEANER, RADIATOR AND FUEL TANK

After washing and painting air cleaner and radiator mount on the tractor body.

Heavy duty type of air cleaner is used in the tractors.

This is of oil bath type cleaner. It consists of a filter element saturated with oil.

At the bottom there is separate oil pun. The air from atmosphere enter in to the gap

and when air takes turn it leaves the impurities there and after it impinging on the

surface of oil and leaves the impurities there and at last air pass through the filter

and cleaning of air is done.

AIR CLEANER

After fitting the air cleaner radiator is attached with engine. The main purpose

of radiator is providing the cooling to the engine i.e. the remove the heat from

engine. Water and alcohol is used as coolant in the radiator.

Page | 58

TYRE MOUNTING

After attached all parts tyre is attached with tractors. After assembly the tyre

alignment of wheel is done.

FOLLOWING ELECTRICAL ITEMS ARE MOUNTED

1. Horn

2. Head Light

3. Brake Light

4. Parking Light

5. Plough Lamp

6. Direction Indicator

SPECIFICATIONS OF HMT TRACTORS

Page | 59

MODEL 2522

SR. NO. PARTICULARS SPECIFICATIONS

1. Bore × Stroke (mm) 95 × 110

2. Engine rated speed (rpm) 2100

3. Engine fly up rpm 2300 + 60

4. Static injection timing (0 BTDC) 14

5. Tappet clearance -

Inlet valve (mm) 0.3

Exhaust valve (mm) 0.4

6. Height of cylinder liner above cylinder block

(mm)

0.06 - 0.12

7. Bumping clearance (mm) 0.75 + 0.4

8. Injection tip (mm) 2.2 – 2.5

9. Injection pressure (bar) 190 + 8

10. Piston ring end gap (mm) -

First ring 0.2 – 0.4

Page | 60

Second ring 0.4 – 0.6

Third ring 0.25 - 0.5

11. Nozzle spray holes 5 × 0.2 × 150

12. H. P. pipe size (mm) 6 × 1.8 × 500

13. Ring colour on injector Utility green

MODEL 3022

Page | 61


1. Bore × Stroke (mm) 102 × 110








(mm)

0.02 - 0.06

7. Bumping clearance (mm) 0.7 - 0.966

8. Injection tip (mm) 3.18







12. H. P. pipe size (mm) 6 × 1.5 × 400

13. Ring colour on injector Golden yellow

MODEL 3522

Page | 62










(mm)

0.06 - 0.12









12. H. P. pipe size (mm) 6 × 1.5 × 500


MODEL 4022

Page | 63










(mm)

0.06 - 0.12






Page | 64




12. H. P. pipe size (mm) 6 × 1.5 × 500


Page | 65

MODEL 4922


1. Bore × Stroke (mm) 102 × 110








(mm)

0.06 - 0.12









12. H. P. pipe size (mm) 6 × 1.5 ×450


MODEL 6522

Page | 66


1. Bore × Stroke (mm) 102 × 110








(mm)

0.06 - 0.12









12. H. P. pipe size (mm) 6 × 1.5 ×450


BIBLIOGRAPHY

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1. Daily dairy (H.M.T.)2. Operator manuals(H.M.T.)3. Wikipedia http://www.wikipedia.org/4. Hmt. Website http://www.hmttractors.co.in/5. Google search https://www.google.co.in/

Page | 68

https://www.google.co.in/

http://www.hmttractors.co.in/

http://www.wikipedia.org/

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