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Английский для агроинженеров пособие Олянича.rtf
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Active Vocabulary

revolution – оборот

piston – поршень

air pump – воздушный насос

stroke – рабочий ход

storage battery-аккумуляторная батарея

generator-генератор

cranking motor-стартер

regulator-регулятор

ignition system-система зажигания

switch-переключатель

TEXT 14

The lubrication system

The most common type of lubrication is the combination of the force feed method and splash lubrication. The lubrication system consists of the oil pump, oil collector, oil filter, oil pipe-lines, oil radiator, oil crankcase, oil pressure-gauge and oil funnel.

When the lubrication system is faulty, the engine operation must be stopped at once.

The oil radiator is used in the lubrication system for oil cooling. It must work there when the air temperature is about 20°C. But regardless of the temperature the radiator must be put into operation if the engine operates with high load in difficult conditions.

The oil crankcase is steel; it forms the bottom of the cylinder block. It keeps the oil. When repairing the crankcase it is necessary to mind that the left front pin screwed into the top of the distributive gears is a special one; it is screwed at small depth in order not to jam the gear of the camshaft. The flange of the crankcase is compressed by the cork gaskets.

The oil collector is attached to the top of the oil pump and consists of the body and filtering screen.

The gear type oil pump with reduction valve is installed inside the oil crankcase. It is fixed to the top of the 4th main bearing by 2 bolts.

The oil filter is installed on the cylinder block from the right side of the engine. It has 2 valves. When the filter gets dirty, one of the valves opens and lets the unlearned oil leak into the lubrication system. When installing the filter on the engine it is necessary to make sure that the gasket is in working order and to lubricate it with oil.

One should check the level of oil in 2-3 minutes after stopping the warmed engine. One must pour the waste oil off the crankcase immediately after driving till it’s hotter. In this case the oil pours off quickly and completely.

The pressure in the lubrication system of a new engine at the speed 60 km/h when gear is direct and oil radiator is switched off must be not less than 343 kPa. The pressure may increase up to 588 kPa when the engine isn’t warmed up and lower up to 294 kPa when the weather is hot. During the process of operation the pressure in the lubrication system will be lowering gradually. When the pressure has lowered up to 118 kPa the engine operation must be stopped at once.

TEXT 15

Why we call it a «diesel» engine

A diesel engine is one form of internal-combustion engine, the latter being an engine from which work is obtained by the combustion of fuel within the engine cylinders themselves. A diesel engine is that type of internal-combustion engine, which injects fuel oil in a finely divided state into a cylinder within which air has been compressed to a high pressure and temperature. The temperature of the air is high enough to ignite the particles of the injected fuel; no other means are used for ignition. Because of this method of ignition, diesel engines are sometimes called compression-ignition engines. This sets them apart from other internal-combustion engines called spark-ignition engines. These latter engines use gasoline or gas as fuel, and the mixture of fuel and air is ignited by an electric spark.

Why, then, do we call this compression-ignition engine by the name «diesel»? Simply because a man whose name was Rudolf Diesel originated in Germany and obtained patents in 1892 on a high-compression, self-ignition engine originally intended to burn powdered coal.

Distinguishing Features of Diesel Engines. How To Recognize a Diesel Engine. Whenever you see an engine you should be able to tell quickly whether or not it is a diesel. Many diesels, at first glance, look like gasoline engines, but it's easy to distinguish them if you keep in mind three essential differences in the way they work. These are: (1) the diesel ignites its fuel solely by the heat of compression, and therefore has no external ignition system; (2) the diesel draws in air alone when it fills its cylinders, and therefore uses no carburetor; (3) the diesel injects its fuel into the cylinder in the form of a spray at high pressure, and therefore uses a fuel-injection pump.

There's another important difference between diesel and gasoline engines - the diesel is built heavier because it must withstand higher pressures, but you can hardly see this from the outside.

Some vertical steam engines of late design look remarkably like diesels, which is not surprising because the designers of these steam engines deliberately copied some of the mechanical features of diesel construction. But the large steam supply pipe gives them away, as does the absence of a fuel-injection pump.

TEXT 16