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Part I

1. Read the text and translate it.

2. Study the vocabulary and prepare your own sentences with them.

3. Be ready to explain the vocabulary words.

Vocabulary

harvester-thresher – зерноуборочный комбайн

reaper – жатка

swath – скос; прокос

cylinder - барабан комбайна

windrower – валковая жатка

pickup attachment – подборщик

cutter bar – режущий аппарат

header – жатка, хедер

reel – мотовило

divider - разделяющий механизм

auger – шнек

mower – косилка

feeder – наклонная камера; подающий механизм

conveyer – элеватор

sieve – решето; грохот; sieve boot - решетный стан

Grain Harvesting Machines Some historical facts

The harvester-thresher is one of our most important power farming machines. It is more often called the "combine" because it combines several operations into a single operation. And today's harvester-thresher is a combination of the ideas, efforts, and energies of men of many centuries.

The modern combine is the result of centuries of development in grain harvesting methods. Two distinct paths of progress have brought us from primitive hand tools to this efficient, fast-working power machine. Today the combine harvests not only all of our small grains, but corn also.

One path would show the evolution of implements for reaping the standing grain; the other would show the gradual development of machines for threshing the cut grain. An early form of reaper marks the beginning of the use of power – animal power – for cutting grain; the "ground-hog" spiked cylinder employed animal-driven sweep powers or tread mills to operate it.

In 1836, ten years before the reaper went into commercial production, the first successful combine was built in Michigan. It cut a 15-foot swath, had a spike-tooth cylinder, was ground-driven, cleaned the grain by means of a fan blast and delivered it into a bag. Although it threshed successfully, climatic conditions caused troubles and the machine was shipped to California in 1854. There conditions were more favorable.

Big combines were the rule during the 1920's and early '30's. The combine was still a big-acreage machine, confined largely in its usefulness to small grain only and to semi-arid climates.

Then, in 1935, came one of those occasional milestones that upset the old pattern completely – that milestone was the one-man combine powered by a two-plow tractor.

Today many sizes and models are available. Combines now harvest all of our small grain crops and each year they harvest more of our vast corn crop.

Swathers or windrowers

These machines are sometimes used as a first operation in harvesting certain grain crops, especially when crops are not dry or ripe enough for direct combining. The machines work fast, cut a wide swath and deliver the cut grain into a windrow that speeds up drying. Then the cut grain is threshed with a combine equipped with a pickup attachment. Both tractor-drawn and self-propelled windrowers are available. They are also used for cutting hay crops, which later are processed further by balers or conditioners. Some windrowers now employ hydrostatic drive for propulsion.

Types, sizes, and capacities of combines

You can describe the size of a combine by the width of swath it can cut. Smaller sizes cut a 5-foot swath and larger sizes as much as a 20-foot swath; some special models, used in other areas, are even wider.

You can classify combines according to the way power is applied:

1. Tractor-drawn - with a combine driven by PTO.

2. Tractor-drawn - with a combine driven by its own engine.

3. Self-propelled - with a combine self-propelled and driven by its own engine.

And you can distinguish two major types:

1. Level-land or prairie type.

2. Hillside type, designed for work on steep slopes: this combine is used in the great wheat fields. Both tractor-drawn and self-propelled hillside models are available. Provision is made for adjusting the cutter bar to the steep slopes and for leveling the thresher and separator units. Recent progress in hydraulic devices has made hillside models more efficient and easier to operate; in fact, some hillside models are leveled automatically both longitudinally and laterally by a pendulum-actuated hydraulic system.

Weight of the different sizes of combines varies greatly - less than 3000 pounds for the smallest, about 9000 pounds for a typical 12-foot, self-propelled model, and more for the largest sizes.

The power needed for a typical 12-foot, self-propelled combine is about 60 engine horsepower; you can draw and operate a 5-foot combine with a two-plow tractor; and an engine of about 30 horsepower is used to operate the mechanism of the 6-foot size when it is not PTO-driven.

The rate of work (capacity) of a certain size depends on many fac­tors – the kind and condition of the crop being combined, topography, moisture conditions, and other factors. But under favorable conditions, one man with a 14-foot, self-propelled machine can "combine" 20 to 30 acres of wheat in a day.