Английский язык. Писарева Л.П. - 44 стр.

   2.   Water sometimes (to get) into the fuel oil.
   3.   A warm engine (to require) only two revolutions on air to start.
   4.   The piston and cylinder walls (to cool) during scavenging.
   5.   The air (to supply) pre-compressed and cooled.

VI.     Ask as many questions as you can:

1..The lubricating oil pump delivers oil through a filter before it is fed to any working
part.
2. The crankshaft has bored ducts conveying the forced lubrication oil to all bearings.
4. Frames are sometimes called “crankcases” for the reason that the frame walls
   enclose the cranks and connecting rods.

VII. Make up your own sentences with the following words:

   to be overloaded, sticky valve, the burnt exhaust valves, to inspect, a loose bearing,
   to fill up, to remove, to reduce engine speed, piston rings.

                                           Вариант V
                                               Text
                                        Engine Lubrication

       The object of lubrication is the maintenance of a film of lubricant between any
two surfaces having relative motion. In the diesel engine there are two general types of
surfaces-those inside the cylinders and those in the bearings. Mineral oils are mostly
used as lubricant.
       Cylinder lubrication has two purpose-to maintain the required film to separate the
liner surface and the surfaces of the piston rings and to act as a seal to prevent gases
from blowing past the rings. These things must be done despite high temperature of
combustion and high pressure resulting from combustion. The first tends to oxidize or
burn the oil and the second tends to squeeze it out from between the surfaces.
       The customary method of applying oil to the cylinder walls is by means of small
pumps, assembled in units or from 2 to 24, known as mechanical lubricators. The oil is
supplied in measured quantities. The object is to supply only enough to maintain a film.
       Bearing lubrication is effected by means of a pressure circulating system. A large
amount of oil under pressure is forced through the bearings. In general, the system is
made up of a sump from which a circulating pump draws oil and discharges it through
the coolers and filters to a manifold which has a branch to each main bearing. Some of
the oil flows out of the ends of the main bearings, while the rest passes through an axial
hole in the crankshaft to the crankpin bearings. Here more oil is lost and the rest passes
through the connecting rod to the wristpin or crosshead bearing. From here all of the oil
may be discharged into the crankpin or a portion may be passed through pipes to the
interior of the pistons for cooling purposes and then return to the sump. In large engines
the cylinders are usually separated from the crankcase so that no black oil and none of
the crankcase oil can be carried up into the cylinder and burned.
                                             44