Ознакомительное чтение (Fact-Finding Reading)

Tractors are the workhorses of modern agriculture. These powerful and iconic machines, thanks to their legendary versatility, play many roles on today’s farms. Let’s take a look at some of the main components of today’s tractors.

The engine is the heart and soul of any tractor. When they were first invented, tractors used steam engines, which were notoriously unreliable, not to mention dangerous. Since the 20^th century, however, tractors have used internal combustion engines that run on a variety of fuels, from kerosene to ethanol and gasoline. Most modern tractors today run on diesel and biodiesel. These powerful engines typically range in size from 18 to 575 horsepower, giving them all of the incredible power they need to tackle any job on today’s farms.

Tractor service in the agriculture industry has increased dramatically over the past century thanks to their legendary ruggedness and durability. Because of their simple yet hardy design, many older tractors that feature manual transmissions are still in use. Unfortunately, these older transmissions are typically unsynchronized, meaning the tractor must be stopped before shifting gears, which can be very inconvenient. Modern tractors on the other hand use synchronized or continuously variable transmissions (CVT), which not only allows for better fuel efficiency but also allows the CVT to shift through an unlimited number of effective gear ratios.

Today’s tractors don’t always follow the classic design, with two large rear wheels and two smaller front wheels. Over time, different configurations have been developed to suit the environment in which they are used. For example, in locations with wet or heavy soils, tractors typically use tracks (such as those found on a “Caterpillar” or tank) because of their superior traction. Other modern tractors feature four wheel drive, either with the classic configuration (two large, two small) or with four large wheels.

Tractor engines put out an enormous amount of power, but in order to be useful that power must be harnessed. That’s where tractor hitches come in. They take the form of draw bars, fixed mounts or three-point hitches and quick hitches that allow power to be transferred from the engine to implements that are typically pulled behind or beside the tractor, and may include attachments such as plows, seeders, tillers, mowers and many others.

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Date: 2015-05-09; view: 654; Нарушение авторских прав