Lec 04 Tractors, Types and Systems.pptx

Tractor and it types

1. Tractors- Types Transmission system- Clutch, Gearbox, Differential and Final drive - Hydraulic system Tractor is a self propelled power unit having wheels or tracks for operating agricultural implements and machines. Its engine is also used as a prime mover for active tools and stationary farm machinery through PTO or belt pulley. Lecture - 04

2. Functions of tractor Tractive power - To pull and haul Rotative power To rotate Hydraulic power To lift and lower propellsion power To travel Tractor power

3. TRACTORS By use By kind of prime movers By travelling systems By driving systems Farm tractor Forestry tractor Industrial tractor Military tractor I.C.E. tractor Steam tractor Electric tractor Wheel type Track/ crawler type Half-track type Two wheel drive Four wheel drive

4. Tractors : Classified based on its power Up to 20 hp 21 - 30 hp 31 - 40 hp 50 hp & above 60 % tractor population in India is 31-40 hp In 1961 tractor manufacturing was started in India – M/s eicher Good Earth

5. Tractor Development 1890 – George H. Harris of Chicago – patented a tractor 1906 – Gasoline Tractor – Charles W. Hart and Charles H. Parr, Iowa 1908 – First Winnipeg tractor trials were held 1911 – First tractor demo was held at Omaha (Nebraska) 1915-1919 – PTO was introduced 1920-1924 – All purpose tractor was developed 1936-1937 – Diesel engine and pneumatic tyre wheels were introduced 1950-1960 – Large scale manufacture of tractors 1960-1961 – Tractor manufacture was started in India – M/s eicher Good Earth 1962-1970 – TAFE- Madras, Hindustan- Baroda, Escorts - Faridabad, International Harvester- Bombay 1971 – Ford Tractor by Escorts 1973 – HMT Tractor 1974 – Pitti and Kirlosker Tractors 1975 – Harsha Tractors 1981 – Auto Tractors 1982 – Universal Tractors 1983-2003 – GCTL, MM, Sonalika , VST, L&T, Bajaj, etc Later – John Deere, New Holland, etc.

6. Tractor Journey

7. Parameters Automobile Tractor Speed upto 200 kmph upto 35 kmph Torque very low high Total reduction ratio 16:1 100-200:1 Suspension Spring Without spring Gear Synchromesh Sliding / constant/ syncro No. of forward gears upto 5 upto 20 No. of reverse gears 1 upto 8 Front / Rear tyre size Same Different Vehicle type On - road Off - road Difference : Automobile vs Tractor

8. Parameters Automobile Tractor Structure Normally closed Open Engine type Diesel / Petrol Diesel Accelerator Foot operated Foot / hand operated Difference : Automobile vs tractor Hydraulics Not available Available

9. CLASSIFICATION OF TRACTOR TYPES S.No Parameters Types of tractors 1. Number of axles * one – Walking * Two – Conventional, riding 2. Number of driven Axles One –Conventional and Walking * Two four wheel drive 3. Ground drive elements *Wheels and tyres,Lungs , strakes * Track- Crawler,Track laying 4. Use of wheels *Traction –conventional * Propulsion/cultivation-Power tiller

10. Classification Basis of Structural Design Wheel Tractor: Tractors, having three or four pneumatic wheels are called Wheel Tractors. Four wheel tractors are most common/popular. Crawler Tractor: . This is also called Track Type or Chain Type Tractor. In such tractors, there is endless chain or track in place of pneumatic wheels. Walking Tractor: Power Tiller is a walking type tractor. This tractor is usually fitted with two wheels. The direction of travel and its controls for field operation is performed by the operator, walking behind the tractor.

11. Classification of Wheel Tractors Based on Purpose General Purpose Tractor : It is used for major farm operations such as ploughing , harrowing, sowing, harvesting and transport work. This tractors have ( i ) low ground clearance, (ii) increased engine power, (iii) good adhesion and (iv) wide tyres . Row Crop Tractor: It is used for furrow crop cultivation. Such tractor is provided with replaceable driving wheels of different tread widths. It has high ground clearance to save damage of crops. Wide wheel track can be adjusted to suit inter row distance. Special Purpose Tractor: It is used for definite jobs like cotton fields, marshy land, hill sides, garden, etc,. Special designs are there for special purpose tractors.

12. Standard row crop tractor The Standard tractor was developed primarily for traction. It is characterized by a drive through the two rear wheels, with centre of gravity located at approximately one third the wheelbase ahead of the rear wheels. Row crop tractors, in addition to being suitable for traction work, are especially adapted for use in row crops, allowing quick attachment of various tillage and cultivation tools as well as implements for such tasks as mowing and handling forages.

13. Four wheel drive with smaller front steering wheel tractor The Four wheel drive tractor with smaller front steering wheel is simply a standard or a row crop tractor with the front wheels also being driven. In regard to price and traction, this type of tractor falls between the standard and the four wheel drive tractor with equal sized wheels. This tractor has become particularly popular in Japan because of its excellent steering and traction characteristics in soft, wet rice fields

14. Four wheel drive with equal sized wheels and articulated frame steering tractor Four wheel drive tractor have been developed so as to be able to produce more drawbar power. The size of 4WD tractors varies from 100 kW to more than 3000 kW. Four wheel drive tractors can be steered by pivoting the tractor in the center or steering wheels.

15. Lawn and garden tractor Lawn and garden tractors have power output of less than 15 kW and are primarily designed for the care of large lawns. They can tow or carry a lawn mower, a sweeper, a snow blower, a bulldozer blade and many other attachments. Because these tractors have very low clearance and are designed for light duty use, they are not generally used for agricultural production.

16. Utility tractor Utility tractors, generally have less clearance than standard or row crop tractors. They are used for many jobs on the farm or ranch and are often equipped with a front loader. Atypical used for such a tractor is clearing a feedlot.

17. Multipurpose / Reversible tractor A Multipurpose tractor is designed to operate in either direction. It not only carries the implement but also furnishes the power.

18.  Skid steer loader tractor Industrial use but it is often used in agriculture when turning room is restricted, such as in a dairy or a fruit storage building. The skid steer cones from the method of turning, which is exactly like that of a crawler. The wheels on one side are braked or reverse, causing the tractor to skid on order to turn.

19. Selection of Tractor - Guidelines Land holding 1 hp for 2 ha Cropping Pattern 1.5 hp / ha (more than one crop) Soil condition less wheel base or high ground clearance, light or heavy soil Climatic condition dry/hot/high altitude – air cooled. Else water cooled Repair facilities availability in local areas Running cost less specific fuel consumption. Specific fuel consumption is the amount of fuel consumed by a tractor or a vehicle for each unit of power output). Initial cost and resale value economic investment Test Report Standards are adopted in manufacture

20. Traction Wheels

21. Tractor Drive Line

22. Tractor Drive Line

23. Example for a Drive Line

24. Tractor Cut Section View & Drive Line

25. Wheel Tractor – “Components” I.C. Engine Clutch Transmission Gears Differential unit Final drive Rear wheels Front Wheels Steering mechanism Hydraulic controls and hitch system Brakes Power take off (PTO) unit Pulley - Draw bar - Control panel - Tractor Systems

26. 27

27. Tractor Clutch Clutch is a device, used to connect and disconnect the tractor engine from the transmission gears and the drive wheels. Clutch transmits power by means of friction between driving members and driven members: Types: Friction clutch, Dog clutch and Fluid coupling

28. Clutch

29. Sliding Gear Transmission If the engine power is constant, it is obvious that for higher torque at wheels, low spped is required and vice versa. So the gear box is fitted between engine and rear wheel for variable torque and speed.

30. Constant Mesh Transmission System Synchronised Trasmission System

31. Differential Drive

32. Differential Differential unit is a special arrangement of gears to permit one of the rear wheels of the tractor to rotate slower or faster than the other.

33. Final Drive System Final drive is a gear reduction unit in the power trains between differential and the drive wheels. It transmits the power finally to the rear axle and the wheels.

34. Tractor Brake Brake is used to stop or slow down the motion of the 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. – Mechanical brake / Hydraulic brake

35. Steering System The System, governing the angular movement of front wheels of a tractor is called Steering system.

36. Steering System

37. Hydraulic and Three Point Hitch It is a mechanism in a tractor to raise, hold or lower the mounted or semi-mounted equipment by hydraulic means. Position Control: Constant depth of ploughing is maintained by automatic adjustment o draft of tractor. The control lever can be operated directly by the driver to raise or lower or hold the implement, mounted on the linkage at any chosen height.

38. Draft Control: The working depth of any implement can be controlled continuously without the need for a depth wheel on the implement. The hydraulic control valve reacts to the changes in the loading in either the top or lower links which are due to changes in the draft or pull required by the implement. If the implement goes too deep its draft increases and is sensed through top or lower links. The control system then raises the implement until the draft is back to the present level and the implement is at the original depth again using the draft control system

39. Tractor with Mounted Implement

40. 3-Point Hitch

41. Draw Bar & PTO PTO-Power Take Off: 540±10 rpm or 1000±10 rpm

42. 6 splines & 21 splines Propeller Shaft Tractor PTO

43. PTO / Belt Pulley PTO – is a part of transmission system. It has a shaft, a shield and a cover. The shaft is externally splined to transmit tortional power to another machine. As per ASAE standards PTO speed is 540 ± 10 rpm. Another PTO is at 1000 ± 10 rpm. Belt Pulley – to transmit power from the tractor to stationary machine.

44. Control panel of Tractor has Main switch Throttle Decompression lever Hour meter Light switch Horn button Battery charging indicator Oil pressure indicator Water temperature gauge

45. Terms associated with Tractor Wheel base – horizontal distance between the front and rear wheels Ground clearance – ht of lowest point of tractor from ground Track – distance between the two wheels of the tractor on the same axle at ground contact. Turning space – diameter of the smallest circle – outer most point of tractor at < 2 km/hr with steering wheels in full lock Cage wheels – spaced cross bars – for more traction in wet field

46. Wheel Base Measurement of center of hubs of front wheels to center of hubs of rear wheel

47. Power take-off horse power (PTO hp) It is the power delivered by a tractor through its PTO shaft. In general, the belt and PTO horse power of a tractor will approximately be the same. It is about 80-85 % of tractor engine power. Drawbar horse power (DB hp): It is the power of a tractor measured at the end of the drawbar. It is that power which is available for pulling loads. It is 50-55 % of engine power.

48. Crawler tractor It is less important today in agriculture that it once was. It is usually used on very soft soil or where stability of the wheel tractor is problem. At one time crawler tractors were larger than wheel tractors and thus they were used on some large farms. Track frame assembly Track chain Steering clutch Steering brake

49. Bull Dozer: Primarily l and leveling is done with the equipment known as bull dozer. It is a high capacity self propelled field machine for doing land development works. It is a crawler tractor provided with two endless track instead of pneumatic wheels. In the front it is provided with an adjustable dozer blade for digging and moving the soil. For road transport, it has to be mounted on a special trailer to avoid damage to tar or concrete roads because of crawler tracks.

50. Power tiller or Walking tractor A Power tiller tractor is a two wheeled tractor guided by hand and used commonly in the rice growing regions. The power tiller is equipped with a rotary tiller and powered by a horizontal single cylinder engine of 5 to 12 kW.

51. Depending upon the mode of operation, three types of power tillers are there - Pull Type – This type of power tiller is used to pull different types of farm implements. Tilling Type – This type of power tiller used to drive the tilling device, such as rotary tiller or a screw blade. General purpose Type – This type of power tiller is used for number of farm operations, including the types defined under pull type and tilling types. The power tiller now being marketed in our country belongs to the general purpose type.

52. Power Tiller Engine Transmission gears Clutch Brakes Rotary unit Main Clutch-Transmission gears-Brakes-Wheels-Rotary unit

53. Power Tiller - History 1920 – Concept Japan is the first country 1947 – First successful power tiller developed in Japan 1963 – Introduced in India 1962 – India – makes like Iseki, Sato, Krishi , Kubota, Yanmar , Mitsubishi, etc manufactured

54. Uses of Power Tiller: Plowing Sowing Weeding & interculture Spraying Harvesting Operation of Thresher Hauling – Transport, etc

55. PT Uses

56. PT Uses

57. Thank You & Good Luck