home  Introduction History Technology Agro Associations Agro Scenario Career Opportunities

  Agricultural Machinery and Equipments
Tractor Spares
Leveling Blade
Grain Drilling Machinery
Harvesting Machinery
Crop Processing Machinery
Oilseed Processing Machinery
Crop Drying Machinery
Hand Tools


An Introduction

The word 'tractor' originated from the Latin word 'trahere', meaning 'pull'. It is an engine or vehicle for pulling wagons or plows. Today, tractors are used for drawing in, towing or pulling objects that are extremely hard to move. One commonly sees a tractor on farms used to push agricultural machinery or trailers that plow or harrow fields. The first tractors from the 1800s and early 1900s, were powered by steam engines. These tractors were phased out due to the instability of the steam engine that caused explosions, or trapped the driver in a belt driven attachment. The successors were built with an internal combustion engine. Technology has found its way into modernizing the tractor. Nowadays, one finds Global Positioning Systems (GPS) and on-board computers attached to farm tractors. With the use of advance technology, corporate-scale farms are using a combination of unmanned tractors and manually driven vehicles to plow the fields.

A tractor is a vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction. Most commonly, the term is used to describe the distinctive farm vehicle. Agricultural implements may be towed behind or mounted on the tractor, and the tractor may also provide a source of power if the implement is mechanized. Another common use of the term is for the power unit of a semi-trailer truck. The first tractors, powered by steam engines, were phased out followed by the internal combustion engine.

Modern tractors are built with a rollover protection system (ROPS) that protects the operator from being crushed in the event that the vehicle rolls over. It was the New Zealand legislation that first required the ROPS to be built in to tractors in the 1960s. Before this system was required, many farmers were killed in accidents when the tractors rolled on top of them, crushing them in the process. Usually these accidents happen when tractors were driven along steep


History of Tractors
In 1892, John Froelich built the first practical gasoline-powered tractor in Clayton County, Iowa. Only two were sold, and it was not until 1911, when the Twin City Traction Engine Company developed the design, that it became successful. The classic farm tractor is a simple open vehicle, with two very large driving wheels on an axle below and slightly behind a single seat (the seat and steering wheel consequently are in the center), and the engine in front of the driver, with two steerable wheels below the engine compartment.

This basic design has remained unchanged for a number of years, but enclosed cabs are fitted on almost all modern models, for reasons of operator safety and comfort. Originally, plows and other equipment were connected via a draw-bar, or a proprietary connecting system; prior to Harry Ferguson patenting the three-point hitch.

Recently, Bobcat's patent on its front loader connection has expired; and compact tractors are now being outfitted with quick-connect attachments for their front-end loaders.
There are also lawn tractors. Cub Cadet, Husqvarna, John Deere, Massey Ferguson and Toro are some of the better-known brands


Uses of Tractors
Farm implements can be attached to the rear of the tractor by either a drawbar or a three-point hitch. The three-point hitch was invented by Harry Ferguson and has been standard since the 1960s. Equipment attached to the three-point hitch can be raised or lowered hydraulically with a control lever. The equipment attached to the three-point hitch is usually completely supported by the tractor. Another way to attach an implement is via a Quick Hitch, which is attached to the three-point hitch. This enables a single person to attach an implement quicker and put the person in less danger when attaching the implement.

In some farm-type tractor, blowtorch cylinders strapped to its sides are used with a pneumatic drill air compressor permanently fastened over its power take-off. These are often fitted with grass (turf) tyres which are less damaging to soft surfaces than agricultural tires. Supposedly industrial bar tires are less damaging to lawns and soft surfaces than agricultural tires, but provide similar traction, and have the benefit of being self-cleaning. Often, these can be seen on road construction backhoes. Equipment costs account for about 20 percent of the total costs of production. The cost for depreciation, interest and insurance can range from $25 to $60 per acre depending on the crop and how intensively the equipment is used.


Modern farm tractors usually have five foot-pedals for the operator on the floor of the tractor. The pedal on the left is the clutch. The operator presses on this pedal to disengage the transmission for either shifting gears or stopping the tractor. Two of the pedals on the right are the brakes. The left brake pedal stops the left rear wheel and the right brake pedal does the same with the right side. This independent left and right wheel braking augments the steering of the tractor when only the two rear wheels are driven. This is usually done when it is necessary to make a tight turn. The split brake pedal is also used in mud or soft dirt to control a tire that spins due to loss of traction. The operator presses both pedals together to stop the tractor. For tractors with additional front-wheel drive, this operation often engages the 4-wheel locking differential to help stop the tractor when travelling at road speeds.

A fifth pedal just in front of the seat operates the rear differential lock (diff. lock) which prevents wheelslip. The differential lock allows the outside wheel to travel faster than the inside one during a turn. However, in traction conditions on a soft surface, the same mechanism could allow one wheel to slip, thus preventing traction to the other wheel. The diff. lock overrides this, causing both wheels to supply equal traction. Care must be taken to unlock the differential, usually by hitting the pedal a second time, before turning, since the tractor cannot perform a turn with the diff. lock engaged.



Useful Steps in Operation of Tractors

  • The tractor should be proceeded slowly and carefully
  • Ditches, gullies and steep embankments should be avoided as far as possible
  • Be aware that a towed trailer or heavy implement can easily upset a tractor's balance and it can overturn the tractor causing hazards
  • Accelerate gradually against gravity's resistance. Tractors tend to flip over backwards while going uphill, especially with a rear implement or when towing
  • Small rocks, holes and bumps should be covered carefully. They can quickly disturb a tractor's equilibrium
  • If possible, always travel directly up or down a hill, never across the slope
  • If cross slope operation is necessary, always turn down the hill with the slope, never uphill into the slope
  • While transporting a load uphill, always attach the load to the front of the tractor and back up the hill
  • When towing a load downhill, use a low gear and let the tractor's engine act as a brake.

Types of Tractors

Compact Utility Tractor
As the name suggests these tractors are modified and assembled to serve various purposes. CUT, as it is commonly called is a smaller version of an agricultural tractor but designed primarily for landscaping and estate management type tasks rather than for planting and harvesting on a commercial scale. Typical CUTs range in from 20 to 50 horsepower (15-37 kW) with available power take off (PTO) horsepower ranging from 15 to 45 hp (11-34 kW). CUTs are often equipped with both a mid-mounted PTO and a standard rear PTO, especially those below 40 horsepower (30 kW). The mid-mount PTO shaft typically rotates at/near 2000 rpms and is typically used to power such implements as mid-mount finish mower, a front mounted snow blower or front mounted rotary broom. The rear PTO is standardized at 540 rpms for the North American markets, but in some parts of the world, a dual 540/1000 rpm PTO is standard and implements are available for either standard in those markets. One of the most common attachment for a Compact Utility Tractor is the front end loader or FEL. All modern CUTs feature a government mandated roll over protection structure (ROPS) just like agricultural tractors. Although less common, compact backhoes are often attached to compact utility tractors.

Farm Tractor
The most common use of the term tractor is for the vehicles used on farms. The farm tractor is used for pulling agricultural machinery or trailers, for plowing, harrowing and similar tasks. The classic farm tractor is a simple open vehicle with two very large driving wheels on an axle below and slightly behind a single seat (the seat and steering wheel consequently are in the center) and the engine in front of the driver with two steerable wheels below the engine compartment. This basic design has remained unchanged for a number of years, but now enclosed cabs are available for many models of farm tractor. There are usually four foot-pedals, for the operator, on the floor of a tractor. The pedal on the left is the clutch. The operator presses on this pedal to disengage the transmission for either shifting gears or stopping the tractor. Two of the pedals on the right are the brakes. The left brake pedal stops the left rear wheel and the right brake pedal does the same with the right side. This independent left and right wheel braking augments the steering of the tractor when only the two rear wheels are driven. This is usually done when it is necessary to make a tight turn.

Engineering Tractor
These tractors are fitted with engineering tools such as bucket, hoe, ripper, dozer blade, and so on. The most common attachments for the front of a tractor are the dozer blade or a bucket. Attached with engineering tools, the tractor is called an engineering vehicle and it is capable of performing complex processes. A bulldozer is one of this kinds of tracked-type tractor attached with blade in the front and a rope-winch behind. Bulldozers are very powerful tractors and have excellent ground-hold, as their main tasks are to push or drag things. Bulldozers have been further modified over time to evolve into new machines which are capable of working in ways that the original bulldozer cannot. One example is that loader tractors are created by removing the blade and substituting a large volume bucket and hydraulic arms which can raise and lower the bucket, thus making it useful for scooping up earth, rock and similar loose material to load it into trucks.

Front Loader
A front-loader or loader is a tractor with an engineering tool which consists of two hydraulic powered arms on either side of the front engine compartment and a tilting implement. This is usually a wide open box called a bucket but other common attachments are a pallet fork and a bale grappler. Other modifications to the original bulldozer include making the machine smaller to let it operate in small work areas where movement is limited. There are also tiny wheeled loaders, officially called skid-steer loaders but nicknamed "Bobcat" after the original manufacturer. These types of tractors are particularly suited for small excavation projects in confined areas.

Backhoe Loader
The Backhoe Loader is a special purpose tractor used mainly in the construction industry. As the name implies, it has a loader assembly on the front and a backhoe on the back. When both the loader and the backhoe are permanently attached, it is almost a huge crane. When the backhoe is permanently attached, the machine usually has a seat that can swivel to the rear to face the hoe controls. Removable backhoe attachments almost always have a separate seat on the attachment. Backhoe-loaders are very common and can be used for a wide variety of tasks like construction, small demolitions, light transportation of building materials, powering building equipment, digging holes, breaking asphalt and paving roads. Some buckets have a retractable bottom, enabling them to empty their load more quickly and efficiently. Buckets with retractable bottoms are also often used for grading and scratching off sand. The front assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or tools.

Garden Tractor
These tractors are small in size and used mainly for domestic plowing and gardening. Garden Tractors have stronger frames, axles and transmissions. Garden Tractors are generally capable of mounting other implements such as harrows, cultivators, sweepers, rollers and dozer-blades. Garden Tractors (also called Mini Tractors) are small, light and simple tractors designed for use in domestic gardens. These are usually designed primarily for cutting grass, being fitted with horizontal rotary cutting decks like ride-on mowers. These type of tractors generally have a horizontally-mounted engine with a belt-drive to a transaxle-type transmission (usually of 4- or 5-speeds, although some my also have two-speed reduction gearboxes or hydraulic gearboxes).

EPA Tractor
An EPA tractor is made just like an automobile, truck or lorry, without the passenger space behind the front seats, equipped with two gearboxes in a row to give the speed of loading heavy weights..

Road Tractor
They are heavy-duty vehicles with large engines and several axles. The majority of these tractors are designed to pull long semi-trailers, most often to transport freight of some kind over a significant distance, and is connected to the trailer with a fifth wheel coupling.

Locomotive Tractor
Amalgamating machines, electrical generators, controls and devices that comprise the traction component of railway vehicles, these tractors are built to move heavy vehicles. They are used mainly for rail car movers.

Tractor Hazards and Safety
Deaths involving tractors contribute to agriculture having one of the highest on-the-job annual death rates -- 20.3 deaths for 100,000 workers nationally in the United States of America. In a 1999 study conducted by the Deep-South Center for Agricultural Health and Safety, it was found that, on average, 21 adults died each year in Florida agriculture in recent years. At least 74 of those deaths involved machinery, including tractors overturning and crushing their drivers. Across the nation, approximately 36 per cent of the agricultural work fatalities in 1997 involved a tractor, and 19 percent involved other machinery, according to the National Safety Council.

Safer tractor operations and the use of protective equipment could prevent many of the deaths and injuries involving tractors. Owners, managers, and tractor operators all play a major role in making tractor operations safer. Owners have responsibilities for providing a safer environment and safer equipment. Managers coordinate maintenance designed to ensure the safety of equipment, as well as safety policies and programs. The final responsibility for making the operation of tractors safer lies with the tractor operators themselves. It's often only when an incident occurs that people become focused on what might have prevented injury or loss of life. The following pages give guidance to agricultural employees on making tractor use safer.



  • Dismounting load from a tractor when the engine is running is not allowed, unless the operation requires it
  • Consumption of alcohol or drugs, including medications that may impair judgment, during work hours or for four hours before starting work should be prohibited
  • Always use hearing protection
  • Carbon monoxide hazards can be detected by signs of severe headeache. Check to see if the exhaust is in a location that exposes the operator to exhaust fumes. There have been instances of carbon monoxide exposure using an open-station tractor in the field
  • If the tractor has a ROPS, securely fasten the seat belt. Do not use seat belts on tractors that don't have ROPS
  • Where possible, avoid operating the tractor near ditches, embankments, and holes
  • Reduce speed when turning and crossing slopes and on rough, slick, or muddy surfaces
  • Stay off slopes that are too steep for safe operation
  • Watch carefully for obstacles and other hazards in the tractor's path, especially at the end of rows, on roads, around trees and in other blind corners.

Tractor Sales and Farmers
Facing market saturation in the traditional markets of the north west (Punjab, Haryana, eastern Uttar Pradesh) tractors sales began a slow and slight decline. By 2002 sales went below 200,000. Manufacturers scrambled to push into eastern and southern India markets in an attempt to reverse the decline, and began exploring the potential for overseas markets. Sales remained in a slump, and added to the market saturation problems also came increased problems of "prestige" loan defaults, where farmers who were not financially able took tractors in moves to increase their families prestige. There are also reported increased misuse of these loans for buying either lifestyle goods, or for social functions. Government and private banks have both tightened their lending for this sector adding to the industry and farmers woes.

By 2004, a slight up tick in sales was witnessed once again. But by 2006 sales once again were down to 216,000 and now in 2007-08 have slid further to just over 200,000. The Tractor Manufacturers' Association of India (TMA) is housed under The Confederation of Indian Industry (CII), New Delhi

The Road Ahead
There has been recent trends in the development of tractors. Two new forms of modernized tractor is a matter of discussion and research among agricultural scientists all over the world, one a 'farmer's vehicle', a universal agricultural machine which could complete all operations in a single pass. The other is a single purpose 'tractor robot', an operator-free agricultural vehicle. The pros and cons of each option are enumerated and requirements for the development of a tractor-robot are in discussion. The tractor-robot has a system of cameras for a round 'vision', a satellite positioning system, movement sensors, control computer and automated motor controls. A prototype of a tractor-robot is presented and assessed; it is equipped with a self-locking cab which can be opened manually if needed, and a standard three-point PTO (power take off) for implements. Tractors are an indispensable agricultural machinery which is all set to bring about revolutionary changes in the world agricultural production.
Untitled Document