Контрольная работа №4 вариант 3

I. Translate into Russian.

MOVING PARTS OF A DIESEL ENGINE

The main moving parts of a diesel engine are those that convert the power developed in the cylinders by combustion to mechanical energy, that is delivered to the shaft. These parts are used to change the reciprocating motion of the pistons in the cylinders to rotary motion at the engine final drive, and may be divided into three major groups:

1. Those parts having rotary motion, such as crankshafts and camshafts.

2. Those parts having reciprocating motion, as, for example, the pistons and piston rings.

3. Those parts having both reciprocating and rotary motion, such as the connecting rods.

Crankshaft. The crankshaft transforms the reciprocating motion of the pistons into rotary motion of the output shaft. It is one of the largest and most important moving parts of a diesel engine.

The crankshaft consists essentially of a number of cranks placed at equal angular intervals around the axis of the shaft. Between the cranks are the crankshaft supports commonly referred to as the journals. Each crank on a crankshaft is made up of the crankpin, which is the journal for the connecting rod bearing, and two crank webs.

The function of the main bearings is to provide supports in which the crankshaft main bearing journals may revolve.

II. Fill in …

Items	Function (purpose, it serves for …)
Piston
Piston rings
Connecting rod
Connecting rod bearings
Camshafts

III. Rearrange these sentences correctly.

1. Is, there, a cylinder liner, the engine block, in, a piston, in which, upwards and downwards movements, makes, known, as a linear motion.

2. When, the piston, its highest point, has reached, stops, a moment, for, it.

3. The stroke, during, open, downward, are, of, the piston, both, valves, inlet.

4. Into, the air, an over pressure, flows, the cylinder, under.

5. The gases, the cylinder, formed, the piston, force, in, expand and exert, on.

IV. Complete the following sentences:

1. The crankshaft, which converts the __________ motion of the piston to rotating motion, must resist the __________ stresses caused by the connecting rod __________ when the piston is at top dead centre.

2. Then the maximum gas pressure acts straight down on the __________ and tends to bend the shaft between the adjacent __________ .

3. The crankshaft must also __________ the torsional forces produced by the change of speed.

4. Medium speed engines have crankshaft usually solid __________ , i.e. made from a single piece, while slow speed engine crankshafts are mostly of semi-built design with crankpins and __________ forged or cast in one piece and shrunk on to the __________ .

5. The type of steel used, which is carbon or alloy steel containing nickel, chromium and molybdenum, is chosen for its strength, resistance to __________ and hardness of bearing surface.

V. Translate into Russian.

1. Детали кривошипно-шатунного механизма (поршень, шатун, коленчатый вал) являются основными подвижными деталями двигателя.

2. Поршень совершает возвратно-поступательное движение, а коленчатый вал — вращательное.

3. Шатун соединяет поршень с коленчатым валом, передает усилия от поршня коленчатому валу и непосредственно преобразует возвратно-поступательное движение во вращательное.

4. Для уплотнения головки поршня ставятся компрессионные (уплотнительные) кольца.

5. Коленчатый вал состоит из кривошипов (мотылей), соединенных между собой рамовыми шейками, которые вращаются в рамовых подшипниках фундаментной рамы.