TILLAGE, TRACTION & LAND DEVELOPMENT MACHINERY  

Course Objective:
The primary objective of this course isto introduce tillage, traction devices and land development machinery used in Agricultural Engineering activities in farms.
Secondly this course introduces soil properties, soil‐tillage‐tool mechanics and traction theory associated with such technologiesthat used in agricultural works.

1. Introduction(4 hours)
1. Soil physical conditions required for plant growth
2. Role of cultivation in producing favorable tilth
3. Basic soil manipulations:
   
1. Cutting and loosening
2. Disintegration
3. Inversion
4. Mixing
5. Compaction
6. Smoothening


2. Dynamic Soil Properties and their Measurement(5 hours)
1. Cohesion
2. Shear and compressive strength
3. Stress–strain behavior
4. Theories of soil failure


3. Mechanics and Geometry of Soil Tool System(7 hours)
1. Determination of passive earth pressure
2. Application of passive earth pressure in design of soil engaging tools
3. Effects of rake angle of soil failure pattern
4. Shallow and deep tine concept
5. Soil compaction by agricultural machines


4. Mechanics of Rotatory Tillage Tools(4 hours)
1. Action of rotatory tillage tools
2. Design parameters of rotatory tillage tools:
   
1. Length of cut
2. Bite length
3. Ratio of peripheral and forward speeds
3. Performance of rotatory tillage tools


5. Land Packers and Clod Crushers(4 hours)
1. Functions of land packers and clod crushers
2. Design parameters of land packers and clod crushers
3. Performance of land packers and clod crushers


6. Zero Tillage and Minimum Tillage Tools(4 hours)
1. Mechanics of zero tillage and minimum tillage
2. Design parameters and working principle
3. Performance of zero tillage and minimum tillage tools


7. Soil Wheel Interaction(8 hours)
1. Mechanics of traction device
2. Rolling resistance and tractive effort
3. Driven and steered wheels
4. Coefficient of traction
5. Drawbar pull and rim pull
6. Traction aids
7. Tyres‐ functions, size and selection
8. Crawlers mounted and wheel mounted machinery


8. Bulldozers(3 hours)
1. General information
2. Crawler mounted versus wheel mounted bulldozers
3. Earth moving with bulldozers
4. Output of bulldozers


9. Scrapers(3 hours)
1. General information
2. Types and sizes
3. Operating efficiency of scraper
4. Performance of wheel type scraper


10. Excavating Equipments(3 hours)
1. Power shovel‐ general information and basic components
2. Size and working principle of power shovel
3. Effect of depth of cut and job conditions on performance of powershovel
4. Dragline‐ general information and basic components
5. Types of draglines
6. Effect of depth of cut and angle of swing on output

Practicals:

1. Study on soil engaging components of agricultural machines
2. Determination of effect of moisture content on dynamic properties of soil
3. Determination of clod mean weight diameter
4. Calculation of passive earth pressure using different models
5. Familiarization with different land development machineries
6. Study on bulldozer with references to blade size and output
7. Study on different types of scrapers and levellers

References:

1. E. McKeys. 1985. Soil Cutting and Tillage. Elsevier, Tokyo
2. Soil Dynamics in Tillage and Traction. USDA Publication.
3. Sineokov, G. N. Design of Soil Tillage Machines. Indian National Scientific Documentation Center, Hillside Road, New Delhi.

Evaluation Scheme:
The questions will cover all the chapters in the Syllabus. The evaluation scheme will be as indicated in the table below.

* There may be minor deviation on mark distribution.