Tractor and Transmission System

15 hp to 100 hp

tractors can generate ___ hp

"to draw"

trahere means __

3-15 hp

two wheel tractors can generate ___ hp

15- 100 hp

four wheel tractors can generate __ hp

Classification of 4WT

compact

standard

< 32 hp

compact tractor hp

32 - 49 hp

standard light tractor hp

50 - 69 hp

standard light medium tractor hp

70-89 hp

standard medium hp

≥ 90 hp

standard heavy tractor hp

wet land rice cultivation (Japan)

first 2WT

Classification of 2WT

1. Traction/Pull type

2. Rotary Type

3. General/Purpose type

traction/pull type

uses drawbar for pulling power

pneumatic tires

wheels used for dry land prep

2WT

steel cage wheels

wheels used for wet land prep

2W

implements used for 2WT

-single bottom moldboard

-two bottom disc plow

-comb tooth harrow

Rotary Type

to cut and pulverize the soil using rotary blades

wheel axle

-axle used for dry land prep

2WT rotary type

front axle

-axle used for wet land prep with FLOATING DEVICE for deep mud conditions

2WT rotary type

General Purpose type

uses drawbar for traction work and

PTO for rotary work

General purpose type

comes with moldboard/disc plow for drawbar and detachable rotavator for PTO

Four Wheel Tractor (4WT)

double axle machine

15 - 100 hp

hp of 4WT

large-scale sugarcane production (America)

1st 4WT introduced in the Phil

draft;

rotary;

lifting

Power is delivered by:

drawbar -> ___

PTO -> ____

hydraulic -> ____

hydraulic three point hitch system

implements for 4WT are mounted using ___

Transmission System

second major component of the tractor

draft power

power from wheels

rotary power

power from PTO

lifting power

power from hydraulic system

methods of Power transmission (4)

1. direct coupling

2. belt and pulley

3. chain and sprockets

4. gears

100%

transmission efficiency of direct coupling

< 100%; belt slippage

transmission efficiency of belt and pulley

due to __

≤ 100%; chain slack

transmission efficiency of chain and sprockets

due to __

transmission efficiency of gears

due to __

Direct Coupling

load is directly connected to the engine by flange device

Ndriver = Ndriven

N1 = N2

formula of direct coupling

Belt and Pulley

two pulleys are connected by a belt

N1D1 = N2D2

N1/N2 = D2/D1

formula of belt and pulley

Chain and Sprockets

speed ratio between the engine and load depends on the number of teeth ratio of 2 sprockets

N1T1 = N2T2

N1/N2 = T2/T1

Formula of chain and sprockets

Gear

-two gears are used side by side

-center to center distance between the shaft of the gears is dictated by the size of the gears

N1T1 = N2T2

N1/N2 = T2/T1

formula of gears

Fundamental law of gearing

the angular velocity ratio between the gears of a gearset remains constant throughout the mesh

- the torque ratio is equal to the reciprocal of velocity rato

SR = (n)in / (n)out

SR = Tout / Tin

formula of gear train

(Teeth)out / (Teeth)in

formula of gear ratio

c. in front of the operator's seat

The stirring wheel of the tractor can be found ___. a. in front of the tractor

b. at the rear of the tractor

c. in front of the operator's seat

d. None of the above

Ballast

The substance that is added to the tractor for the purpose of changing traction and stability.

Power take-off drive

The power drive found at the rear of the tractor that propels power implements and stationary machines.

540 rpm

The standard rpm of a tractor's PTO drive

Power tiller

A two-wheeled, hand-operated tractor used primarily as a substitute for draft animals.

Cagewheel

An attachment to a tractor's rear wheel to increase traction.

Front Ballast

-Improves stirring for 2-wheel drive

- Improves stirring and traction for 4-wheel drive

Wheel Ballast

- Improves traction for two- and four-wheel drive tractors

Stirring wheel

The part of the tractor that controls the travel direction of the machine.

Automatic draft control

A tractor device that automatically raises or lowers the implement in operation to maintain a given draft.

final drive

The gear reduction of a tractor located in its power train between the differential and the driving wheel that transmits power at low speed but large torque to the rear axles and wheels.

Lugging ability

The inherent characteristic of tractors to maintain or to produce increased drawbar pull even if the speed is reduced.

540 rpm

The lower PTO speed of a standard four-wheel tractor is ___.

Differential

The special arrangement of gears that permits driving member to rotate slower or faster than the other and permits operation of driving wheels at different speed for easy turn

540 rpm

The standard power-take-off speed of a tractor

35 mm

The standard shaft diameter of a PTO shaft

60 kw

If a farm tractor is rated at 80 horsepower, its

metric equivalent is ___.

Drawbar

The part of the tractor to which implements are hitched

concrete road

The coefficient of traction for wheel-type tractor is

highest for ___.

Differential brake

The part of a tractor that retards or stops one wheel

during operation to be able to make short turn. Differential brake

power take-off

any of several methods for taking

power from a power source or from a tractor and transmitting

it to an application such as an attached implement or

separate machines.

PTO

used for driving field machines such as

rotary plow, hay baler, corn picker, self-unloading forage

wagon, irrigation pump, etc

Cylinder liner

The part of the tractor engine where pistons slide back

and forth and is replaced or rebored when damaged

single hitch point system

A trailing-type implement is hitched to the tractor at

the tractor's ___.

27.89%

Wheel slip tests of a tractor showed that its wheel

rotates by two-and-a-half revolutions at 20-meters

distance. If the tractor wheel has 2-meter diameter, what

is the percentage slip of the tractor wheel?

rotary plow

The PTO drive of a tractor is used to power ___.

c. tractors that have four running wheels and all wheels

are driven by an engine

Four-wheel-drive tractors are ___.

a. tractors that have four running wheels

b. tractors that have four running wheels and the two

rear wheels are driven by an engine

c. tractors that have four running wheels and all wheels

are driven by an engine

d. None of the above

Wheel tread

The center-to-center distance between two front

wheels or two rear wheels

right side of the operator

Hydraulic control levers on typical four- wheel tractors

are located at the ___.

378.4 N

If the tractor wheel delivers a torque of 378.45 N-m when

rotavating a paddy field, what is the force at its wheel if its

diameter is 2 meters?

Straight spline

The PTO shaft profile for 35-mm nominal diameter shaft,

6 splines, 540- rpm rated speed

Involute spline

The PTO shaft profile for 35-mm nominal diameter shaft,

21 splines, 1000- rpm rated speed.

Engine horsepower

The power measured at the flywheel or at the

crankshaft of a four-wheel tractor.

625 kgf

A tractor weighs 2.5 tons and runs in a deep mud soil

rotavating a paddy field. Estimate the rolling resistance of the

tractor wheel during operation?

Tractor ground clearance

The distance between the supporting surface and the

lowest point of the tractor

Rated engine speed

The speed, in revolution per minute, specified by the

manufacturer

80%

The weight of the tractor includes its total weight, the

different tools, the fuel tank filled to ___ capacity, and with

the normal amount of cooling water and lubricating oil when

the tractor is at work.

1/3 of the wheel base in front of its rear wheel axle

The center of gravity of a standard two-wheel-drive tractor

is located at ___.

2.0 ha/hr

A tractor pulls a 2.0meter-wide heavy-duty offset disk

harrow at 10 kph operating speed. What is the theoretical

field capacity of the machine?

its mid center

The center of gravity of a four-wheel drive tractor is

located at ___.

USA

John Deere tractor is made from ___.

United Kingdom

Massey Ferguson tractor is made from ___.

USA

Ford tractor is made from ___.

Korea

Goldstar tractor is made from ___.

Finland

Valtra Velmet tractor is made from ___.

Brazil

Maxion tractor is made from ___.

824.53 liters

If the specific fuel consumption of the tractor engine is

350 g of diesel/kW-hr during plowing operation, how much

diesel will the 300 hp tractor will approximately consume in

8 hours operation? Assume a specific gravity of diesel of

0.76.

261 hp

The indicated horsepower of the tractor engine is

300 hp. What is its expected power take off

horsepower of the tractor?

225 hp

What is the drawbar power of the tractor in Item 56

above?

Hitch point

The pivotal point of connection of hitch to the

tractor or the center of the articulated connection

between link and the implement.

Auxiliary PTO

An external shaft of an agricultural tractor other than the

PTO that provides rotational power to implements that are

usually front- or side-mounted.

70.82 liters per hour

The specific fuel consumption of a 250 hp tractor engine is

300 g of diesel/kw-hr. How many liters of fuel will the tractor

consume?

1 %

The effective drawbar pull of a tractor is

reduced by ___ for every percent of grade.

Drawbar hitch system

A hitch system for a tractor suitable for

large, heavy implement for trailing.