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1. Farm Power and Machinery
(AgEn262)
Chapter_1
Concepts of Agricultural mechanization
By: Asmamaw M..

2.  Agricultural mechanization is a special field of Agricultural Engineering.
 It is a way of improving farming operations through the use of machines, equipment
and structures to enhance productivity.
 It includes production, distribution and utilization of a variety of tools, machinery and
equipment for the development of agricultural land, planting, harvesting and primary
processing.
 Agricultural mechanization involves the design, manufacture, distribution, use and servicing
of all types of agricultural tools, equipment and machines.
Examples of agricultural mechanized operations
 Land clearing and preparation, Planting , Fertilizer, herbicide and pesticide applications.
 Harvesting of crops, Feeding of animals etc.
1.1. Definition of Agricultural mechanization

3. 1.2. levels of mechanization
Based on the power sources mechanization in any area is characterized into 3 levels.
1. Low Mechanization Level (human power-based mechanization )
 Manual power used exceeds 33%. efficiency and productivity are very low
 hand-tool technology,
2. Fair Mechanization Level: (animal power-based mechanization)
 animal power used is 34 – 100%. Uses draught animal technology
 It is source of power on the farm all over the world particularly in developing countries.
 Different animal sources are: Camels, Horses, mules, cow etc.
3. High Mechanization Level (mechanical power-based mechanization)
mechanical power used is 67 – 100%
 Uses mechanical power technology by integrating electrical sources ( eg. tractors

4. 1.3. Farm Mechanization
 Farms Mechanization means the use of machines for conducting agricultural operations,
replacing the traditional methods which involve human and animal labor to increase crop
yield.
 This includes the development, application and management of all mechanical aids for field
operation, water control, material handling, storage and processing.
 Mechanical aids include hand tools, animal drawn implements, power tillers, tractors, engines,
electric motors, grain processing and hauling equipment.
 Farm mechanization implies the use of mechanical technology in the varied farming
operations like sowing, harvesting, threshing, levelling, watering, spraying, weeding etc.

5. 1.4. objectives of farm mechanization
 Improve irrigation facilities, introduction of high yielding varieties.
 Use of higher doses of fertilizers and pesticides.
 Helps for proper utilization of basic inputs like water, seed and fertilizer, optimum placement
of the seed and fertilizer, ploughing, removal of weeds, leveling of uneven land and land
reclamation.
To mechanize the farm technology it must be consider the following:
 There must be suitable equipment developed for timely production of goods.
 Manufacturing and availability of machine spare parts must be adequate to meet needs of end
users of such machinery.

6. 1.5. Benefits of farm mechanization:
1. Timeliness of operation
2. Precision of operation
3. Improvement of work environment
4. Enhancement of safety
5. Reduction of drudgery of labor
6. Reduction of loss of crops and food products
7. Increased productivity of land
8. Increased economic return to farmers
9. Improved dignity of farmers
10. Progress and prosperity in rural areas

7. Dis advantages of agricultural mechanization:
There are various negative effect in adopting farm mechanization:
1. It is expensive to operate and maintain machine if damage occur
2. It displaces workers
3. Heavy machines compact the soil due to movement
4. It cause environmental pollution from smoke, chemical and
fertilizer usage
5. It brings about landscape degradation from continues excavation.

8. Limitation of agricultural mechanizations:
1. Economic limitation
a. Most farmers are poor
b. High cost of machines
c. High cost of maintenance
2. Technical limitation
a. Lack of trained man power.
b. Most machines are not adapted to our local environment
c. No training schools for installation
d. Lack of availability of suitable farm machines for different operations
e. Lack of co-ordination between research organization and manufacturers

9. Limitation of agricultural mechanizations:
3. Lack of maintenance
a. Lack of repair and servicing facilities for machines
b. There no enough trained personnel
c. Replacement parts are not available
d. Inadequate quality control of machines
4. Small farm holdings
a. Small and fragmented land holdings
b. Less investing capacity of farmers
c. Fragmentation of farmland
d. Agriculture is mostly practiced by traditional ways
e. Their are no enough cooperative farmers to handle large farm

10. 1.6. Current Status of agricultural mechanization in Ethiopia
 Though Ethiopia has a long history of agricultural practices, the development of agricultural
mechanization is still minimal.
 Farm power is mainly dependent on oxen-draft and human muscle operating using
traditional farm implements.
 Oxen-pulled maresha is the dominant farm implement in cereal-based systems whereas
hand-hoe is the main farm implement used in agroforestry systems.
 The level of tractor-based agricultural machinery use is relatively better in wheat dominated
cropping systems where harvesting and threshing are done using combiners.

11. 1.6. Status of agricultural mechanization in Ethiopia
 The uptake of agricultural mechanization in Ethiopia is low with less than one percent of
agricultural plots plowed with a tractor.
 However, in recent years the uptake of agricultural machinery has accelerated.
 We note an impressive increase in imports of combine-harvesters and of tractors,
seemingly associated with the increasing costs of agricultural labor and animal traction,
substitutes for agricultural mechanization.
 We estimate that a quarter of the area in Ethiopia planted to wheat – the fourth most
important cereal in the country – is currently harvested by combine-harvesters, and they are
widely used in the major wheat growing zones in the southeast of the country in particular.

12. 1.6. Status of agricultural mechanization in Ethiopia
 Private mechanization service providers have rapidly emerged.
 Smallholders in these wheat growing zones rely heavily on agricultural machinery rental
services for plowing, harrowing, or harvesting.
 We find that mechanization is associated with significantly lower labor use, and that the
adoption of combine-harvesters – but not tractors – is significantly associated with higher
yields, seemingly due to lower post-harvest losses.

13. Farm Power and Machinery
(AgEn262)
Chapter_2 Farm machinery
By: Asmamaw M..

14. 2.1. Definition of farm machineries
 Farm machinery is mechanical devices, including tractors and implements, used in farming
to save labor. Or it is all machines and tools that are used in the production, harvesting, and
care of farm products.
 Farm machines include a great variety of devices with a wide range of complexity: from
simple hand-held implements used since prehistoric times to the complex harvesters of
modern mechanized agriculture.
 It includes trailers that are used to transport agricultural produce or agricultural
production materials between a local place of storage or supply and the farm, agricultural
tractors, threshing machinery, hay-baling machinery, corn shellers, hammermills, and
machinery used in the production of horticultural, agricultural, and vegetable products.

15. 2.2. Type of farm machineries
Implements can be divided into five primary categories, based on their use:
1.Irrigation Machinery: helps to keep crops watered at appropriate levels, and usually includes
central pivot irrigation systems and pump units.
2. Soil Cultivation Implements: used to plow the soil and prepare it for cultivation. Some
examples of soil cultivation equipment are spike, drag, and disk harrows; power harrow parts; mold
board plows; and tillers in several varieties.
3. Planting Machines: designed to plant saplings and seeds over broad areas of land, after the soil
has been cultivated. Precision drills, broadcast seeders, seed drills, air seeders, and transplanting
equipment all fall under this category.

16. 2.2. Type of farm machineries
4. Harvesting Implements: used to bring in the crops once they have reached full maturity.
Trailers, diggers, and pickers are a few examples of this kind of equipment.
5. Miscellaneous Agricultural Equipment: used in corollary agricultural activities, such as
hay-making, shredding, and loading.

17. Soil
Cultivation
Types of
Implements
Irrigation
Implements:
Implements
Harvesting

18. 2.3. Materials of construction of farm equipment
 Strength, durability and services of a farm implement largely depend upon the quality of
material used.
 Selection of proper material for a particular application is of critical value.
 Proper treatment of the selected material affects the initial cost and running cost as well as
durability and performance of the machine.
 Implement parts/components/ should be designed to utilize the lowest cost materials which
can perform satisfactorily and provide adequate life.
 Use of high cost materials and expensive treatments sometimes become unavoidable to make
for a deficiency in the original design.
 so, farm machines are constructed with different materials to give it strength and
make durable.

19. Tillage equipment

21. Sowing equipment

22. Intercultural equipment

23. Plant protection equipment

24. Methods of heat treatment .

25. Harvesting and threshing equipment .

26. Farm Machinery

27. 27

28. Applications of ferrous martials

29. Applications of ferrous martials

30. 2.3. Materials of construction of farm equipment
b.

31. 2.3. Materials of construction of farm equipment
b.

32. 2. 4.Source of farm power
 Farm machinery refers to hand tools, animal drawn implements and power-operated
equipment's used for performing various field operations in the production of agricultural
crops.
 For a machine to function, it must be provided with an input of physical work by a source of
power: human, animal or mechanical power.
1. Human Power
 It’s the main source for operating small implements & tools at the farm.
 Stationary work like chaff cutting, lifting, water, threshing, winnowing etc. are also done by
manual labor.
 An average man can develop maximum power of 0.1 hp for doing farm work.

35. 2.4. Source of farm power
2. Animal Power
 Power developed by an average pair of bullocks 1 hp for usual farm work.
 Bullocks are employed for all types farm work in all seasons.
 Besides bullocks, other animals like camels, buffaloes, horses, donkeys, mules and elephants are
also used at some places.

36. 2.4. Source of farm power

37. 2.4. Source of farm power (cont’d…)
3. Mechanical Power
 This includes stationary oil engines, tractors, power tillers and self-propelled combines.
 Internal combustion engine is a good device for converting liquid fuel into useful work
(mechanical work). These engines are two types
 Spark ignition engines (Petrol or Kerosene engine)
 Compression ignition engines (Diesel engines)
4. Electrical Power
 They used mostly in the form of electrical motors on the farms.
 Its maintenance and operation needs less attention and have smooth running.
 It is used for water pumping, dairy industry, cold storage, farm product processing, fruit
industry and many similar things.

38. Mechanical Power

39. Mechanical Power

40. Electrical Power

41. 2.4. Source farm power (cont’d…)
Renewable Energy
 It is the energy mainly obtained from renewable sources of energy like sun, wind, biomass etc.
 Biogas energy, wind energy and solar energy are used in agriculture and domestic purposes with
suitable devices.
 It can be used for lighting, cooking, water heating, space heating, water distillation, food
processing, water pumping, and electric generation.
 This type of energy is inexhaustible in nature.

42. Renewable energy

43. 2.5. Internal Combustion Engine
Engines
 An engine is a machine having moving parts and designed to convert one form of energy into
another forms of energy to give us desired work output.
 It is convert one form of energy into mechanical energy.
 It is converting thermal energy into mechanical energy or power to produce force and motion.
Heat engine:
Heat engine is a machine for converting heat(developed by burning fuel) in to useful work.
It can be said that heat engine is equipment which generate thermal energy and transforms in into
mechanical energy.

44. Classification of heat engine
Based on combustion of fuel
1. External combustion engine
2. Internal combustion engine.
 In internal combustion engine, the combustion of fuel takes place inside the engine cylinder and
heat is generated within the cylinder.
 This heat is added to the air inside the cylinder and thus the pressure of the air is increased
tremendously.
 This high pressure air moves the piston which rotates the crank shaft and thus mechanical work
is done

45. 2.5. Internal Combustion Engine

47. Group Assignments
1. In the world search and list all types of available mechanized and non mechanized
farm machineries based on their use (type).
a. Explain their function, working mechanisms and source of power,
b. Identify their advantages, disadvantages, and limitation (problems) on that farm
machinery's ,
c. Identify the components(parts) and constriction materials of that farm equipment. And
also put the reasons what that materials are selected to construct the farm machineries.
d. Based on the nature of the soil, topography of earth, wither conditions and values of the
farmers, identify the current exist problem on the agriculture sector in Ethiopia to
mechanize the agriculture and as agricultural economics put or suggest your solution (
necessary farm machinery) to increase the crop yield.

48. End of Chapter 2
Next Lecture
Chapter 3: Transmission of power
48