III . Переведите предложения на английский язык:
1. В холодную погоду двигатель перед пуском следует прогреть.
2. После пуска двигателя его работу проверяют по показателям контрольно-измерительных приборов.
3. Особое внимание следует обратить на работу систем смазки и охлаждения:
4. Перед пуском двигатель должен быть тщательно оcмотрен.
5. Убедитесь, что в топливе нет воды.
6. Необходимо опробовать системы смазки и охлаждения до пуска.
7. Информируйте мостик о готовности двигателя.
8. Повышение температуры в системе смазки показывает, что подшипники перегрелись.
9. Записи в машинном журнале должны производиться по крайней мере каждый час.
I V. Перевести словосочетания на русский язык:
damaged exhaust valve seat
worn ring groove
to cut off from
to weld in place
to use heat
grinding
wear rate
in due time
shut-off fitting
ultrasonic test
to verify the scope of work
Вариант 8 I. Read and translate the text “Diesel combustion” into Russian.Conditions for good combustion must be proved because the diesel engine has to handle the entire job of mixing and igniting fuel inside the cylinder in an extremely short time. Successful combustion depends on the following conditions:a) fine atomizationb) high temperature for prompt ignitorc) high relative velocity between fuel and air particlesd) good mixing of fuel and air.Atomization and spreading of the fuel depend largely on the injection system. Compression ratio, cylinder dimensions and cooling arrangements determine the temperature conditions. Mixing depends on proper relation of the injection pattern, the intake system and the shape of the combustion space formed by the cylinder head, the cylinder walls and the piston crown.There are different types of combustion chambers. The main of them are:1) direct injection;2) precombustion chamber;3) turbulance chamberDirect – injection Engines. Most of the solid – injection engines turning at less than 400 r.p.m. and many running at higher speeds employ direct injection, that is, the oil is sprayed directly into the clearance space of the cylinder. The spray valve has from 5 to 10 orifices, of about 0.01 to 0.002 in diameter. This separation of the oil charge gives the necessary diffusion and insures that the oil drops penetrate and mix with entire air charge Atomization and diffusion of the oil is brought about solely by the velocity energy of the oil spray.Precombustion – chamber Engines. This engine is one in which a small separated part of the combustion chamber communicates with the main part in the cylinder, through one or more small passages or orifices and the fuel is injected into the small (precombustion) chamber opposite its point of communication with the cylinder. In an engine of this type all of the fuel injected must necessarily pass through the precombustion chamber.Turbulence – chamber Engines. Turbulence – chamber engines are similar in form and arrangement of parts to the precombustion – chamber type, the main difference between them being one of proportions, in that the separated portion of the combustion chamber and cross –sectional area of the passage (or passages) between the latter and the main chamber are smaller in the precombustion – chamber engine. In a turbulence – chamber engine a section through the chamber which cuts the communicating passage in halves is at least approximately circular in form, whereas in a precombustion – chamber engine it is most likely to be rectangular. In the turbulence – chamber engine the energy necessary to accomplish a rapid and through intermixture of the air and fuel charges is derived from two sources – the kinetic energy of the fuel jet and that of the swirl of air in the turbulence chamber. If fuel is injected directly into the main combustion chamber, in which there is little or no turbulence, all of this energy must be supplied by way of the fuel jet, from which it is natural to conclude that in a turbulence – chamber engine it is possible to work with lower injection pressures than in an engine having direct injection into the main combustion chamber. This is one advantage of the turbulence – chamber engine.II. Answer the following questions to the text:1. What are the necessary conditions for successful combustion?2. What determine the temperature conditions inside engine cylinder?3. What kind of combustion chambers do you know?4. What engine use direct injection?5. What is a precombustion – chamber engine?6. What is the difference between the turbulence chamber engine and the precombustion – chamber engine?III. Translate the following sentences into English.1. Судовые двигатели преимущественно имеют непосредственное впрыскиваниетоплива.2. Двигатели, работающие на максимально высоких скоростях, используют камеры особых конструкций, т. е. вихревые.3. Топливо подается в камеру сгорания или впрыскивается в особую предкамеру под давлением в 100 а.т.м. и это зависит от типа камеры сгорания.4. В двигателях с непосредственным впрыскиванием топливо подается в камеру сгорания.5. Для интенсивного смесеобразования в быстроходных двигателях применяется вихревая камера.III. Give synonyms to the following words.To separate, portion, cross, area, thoroughly entire, to drop, passage, to use, device, medium to fit, to feed.IV. Point out the suffixes in the following words and translate them into Russian.Formation, considerable, clearance, effective, receiver, partially, similar, likely, suitability, turbulence, expansion, useful, passage, feature, loosen, gaseous, careless, particularly, viscosity.
Вариант 9 I. Read and translate the text “Engine Lubrication” into Russian.The purpose 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. This oil must be applied in small quantities for lubrication of the cylinders, but if it is used for bearing lubrication, the oil can be applied in any desired quantity and used repeatedly.Cylinder lubrication.Cylinder lubrication has two purposes – 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 or force the combustion gases past the rings. The principal problem is to produce an oil that will not break down and form carbon and gum- my lacquer that will cause the piston rings to stick or break. The customary method of applying oil to the cylinder walls is by means of small pumps assembled in units of from 2 to 24, known as mechanical lubrications. The oil is supplied in measured quantities, only enough to maintain a film and continuously replace that portion of the oil that is burnt or blown past the rings.Bearing LubricationBearing lubrication is effected by means of a pressure circulating system. A large amount of oil under pressure if 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 bearings. 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 axial holes in the connecting rods to the wristpin or crosshead bearings. From here all of the oil may be discharged from the bearings 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.II. Translate the following words and word-combinations from English into Russian.A film of lubricant, to have relative motion, to separate, to act as a seal, to prevent gases from blowing, past the rings, to oxidize the oil, to squeeze the oil out, to apply oil, to assemble in units, measured quantity, is effected by, pressure circulating system, large amount, to force through, to draw and discharge, a manifold with a branch, axial hole, crankpin bearing, wrist-pin bearing, crosshead bearing, a portion of oil, to pass through the pipe, interior of the piston, a sump.II. Give English equivalents.Чтобы смазать, поддерживать масляную пленку, движущиеся части, система смазки под давлением, сверленные отверстия, передавать масло к, подшипники мотылевых шеек, стекать в картер, мокрый картер, избыток смазки, сухой картер, предотвратить образование смоло- и лакообразного нагара, залипание колец, прорваться через, нагнетать, мотылевый подшипник, шатунный подшипник.III . Answer the questions .1. Why is it necessary to lubricate the engine parts?2. What oil is used for lubrication?3. What mechanism supplies oil to the cylinder walls?4. What lubrication system is used to oil bearings?5. What quantity can oil be applied in when lubricating cylinder and bearings?6. What way does oil pass to the crankpin bearings?7. Why is it necessary to clean the oil before supplying it to the system?IV. Translate sentences into English.1. Смазка предотвращает износ деталей двигателя.2. Смазка цилиндров имеет 2 цели. Масляная пленка разделяет поверхности втулоки поршневых колец. Она предотвращает прорыв газов за кольцами.3. Для смазки подшипников используется циркуляционная система под давлением.4. Циркуляционный насос засасывает масло и подает его через охладители и фильтры к трубопроводу.5. Масло подается к поршневому подшипнику через отверстие в шатуне.6. Механические лубрикаторы подают масло в небольших количествах.
Вариант 10I. Read and translate the text “Engine Cooling System” into Russian.When fuel burns in the cylinders of a diesel engine only about one-third of the fuel’s heat energy changes into mechanical energy and then leaves the engine in the form of brake horse- power. The rest of the heat shows up in hot exhaust gases, frictional heat of the rubbing surfaces and heating of the metal walls which form the combustion chamber, namely, the cylinder head and piston. The cooling system job is to remove the unwanted heat from these pasts so as to prevent:1. Overheating and resulting breakdown of the lubricating oil film which separates theengine rubbing surfaces.2. Overheating and resulting loss of strength of the metal itself.3. Excessive stresses in or between the engine parts due to unequal temperature.Cylinder heads and cylinders are generally provided with jackets through which coolingwater is circulated. Pistons transfer their heat to the cylinder walls and to the lubricating oil. Many engines use oil coolers to remove the heat in the lubricating oil. The heat balance of an engine and the amount of heat absorbed by the cooling water vary with the type of engine and the design of cylinders, exhaust manifold, pistons lubricating oil system and any other equipment which may be cooled directly or indirectly by the circulating water.Closed Cooling SystemIn closed cooling systems the jacket water is recirculated through closed heat exchangers. A heat exchanger is a device that transfers heat from one fluid to another. Thus, in closes systems, the same water remains in the system indefinitely and is recooled without exposure to air. The heat exchanger may be water-to-water (shell-and-tube type) or water-to-air (radiators and through only once if the supply is ample and there is no need to conserve it. Scale deposits are not as serious in heat exchangers can be easily cleaned. In the radiator type of a closed system air blown by a fan cools water within the tubes of the radiator. The water is not exposed to the air and there is no evaporation. Both salt and fresh water are used for cooling system. When a separate fresh-water system is employed, an extra fresh-water cooler and pump for circulating sea water through this cooler must be available. The advantages of the separate fresh-water system are that higher temperatures of the cooling water can be used; salt-water fittings are not necessary beyond the fresh-water cooler, muddy (dirt) and other objectionable over-board water cannot get into the engine jackets, main circulating-water piping and circulating-water pumps.The temperature of the discharge from sea-water cooling systems shouldn’t exceed 130ºF, because higher temperatures lead to deposit of solids on the cooling surface. When fresh water is used for cooling, the discharge water temperature should not exceed 160ºF. to maintain efficiency the temperature of the cooling water shouldn’t fall below 100ºF. Under no account must a large amount of cold water be supplied suddenly into a hot engine. Such sudden cooling would cause unequal contraction of the structural and working parts, would crack cylinder heads and cylinders and lead to seizing of pistons.II. Answer the following questions.1. In what form does mechanical energy leave the engine?2. What’s the cooling system’s job?3. What are cylinder heads and cylinders provided with?4. Where do pistons transfer their heat?5. What is the heat exchanger?6. What types of heat exchangers do you know?7. What should you know about the temperature of cooling water?8. What can a large amount of cold water supplied into hot engine cause?III. Give extensive answers.1. Why is it necessary to cool the engine?2. What cooling medium can be used?3. Why is it preferable to cool the piston with oil?4. Why is sea water used generally in the coolers?IV. Translate into Russian a) defining the prefixes in the words.Unwanted, unequal, uncomfortable, indirectly, insufficient, indefinitely, incorrect, irregular, discharge, disconnect, remove, recirculate, recover, reheat, recool.b) combine the following words with the above and translate them into Russian.Heat, heating, stress, conditions, cooling, water level, timing, supply, operation, combustion products, heat balance, as much heat as possible, cold water, circulating pump.V. Find synonyms to the following words in the text.Thermal energy, to alter, to escape, burnt gases, warm, cylinder cover, function, to eliminate, undesirable, failure, to divide, to supply, to transmit, quantity, liquid, sufficient, additional, to keep.VI. Translate sentences paying attention to the Infinitive functions.1. The cooling system job is to remove the undesirable heat from the moving parts of the engine.2. Many engines use oil coolers to remove the heat in the lubricating oil.3. To transfer heat from one fluid to another a heat exchanger is used.4. Cooling is also provided for the exhaust manifold to prevent high temperatures.5. The plant utilizes a heat exchanger to recover heat from exhaust gases.VII. Change the following sentences into the Passive Voice.1. Fresh water cools the piston.2. The burning fuel transfers the heat to the metal parts of the engine.3. Sea water cools the oil and scavenging air.4. The engine drove the pump.5. We provided an oil film between the rubbing surfaces.VIII. Translate sentences from Russian into English.1. Цилиндровые крышки и цилиндры обычно снабжены рубашками.2. Масляный холодильник используют для удаления тепла из смазочного масла.3. Назначение системы охлаждения – предотвратить перегрев трущихся поверхностей.4. Тепловой баланс двигателя может меняться в зависимости от типа двигателя и конструкции цилиндров, поршней и системы смазки.5. Теплообменники могут быть водяного и воздушного охлаждения.6. Охлаждение пресной водой вызывает меньшее отложение осадков и накипи, меньше вызывает коррозию.
Вариант 11 I. Read and translate the text “Turbochanging System” into Russian.To increase the available output of a diesel engine of given main dimensions the engine is connected with one or more exhaust-gas turbine-driven compressors and air coolers: an arrangement which is generally known as turbocharging. The only difference between an engine equipped in this manner and a normally aspirated engine is that the former operates at an increased pressure level. The exhaust gas drives a turbine which, in turn, drives a centrifugal compressor which increases the air pressure before the reciprocating scavenging air pumps. Since the density of scavenging air is increased by the pressure rise in the turbo-compressor and the subsequent cooling, a larger quantity of air by weight is entrapped in the cylinder which, in turn, permits the combustion of a larger quantity of fuel and gives a higher available output. Each turbo-charger consists of a single stage or two-stage centrifugal compressor and axial turbine which are assembled on the same shaft. Rotation of the rotor depends on the engine load and scavenging resistance, since the unit is connected to the engine without any mechanical transmission. The turbo-charged engine is maneuvered in the same manner as a normally aspirated engine. MAK engines use only pulse turbocharging and to meet this requirement cylinder numbers which permit good grouping of the turbocharger connections are employed. A distinction is made between three-pulse charging for 6 – 9 and 12 cylinder engines with cams specially timed for three-pulse mode and four-pulse charging for 8 and 16 cylinder engines with completely different timings for the four-pulse mode. The disadvantage of pulse charging for highly-supercharged engines compared with the constant pressure charging is the fact that during the full load the single-stage exhaust turbine can only utilize the lower part of the very high exhaust gas pressure wave. But this is the advantage at part load or reduced power. Pulse charging has a further advantage that the engine can adapt very quickly to sudden changes in load. With exhaust gas turbo-charging it has proved possible to triple the power obtained from the swept volume of a diesel engine.II. Compose your own sentences with the words.Full load, drive, larger quantity, increase.III. Translate the following word-combinations into Russian.Burning more fuel oil, at a pressure higher than atmosphere, exhaust-gas turbine-driven compressor, air cooler, is generally known, the only difference, normally aspirated engine, pressure level, reciprocating scavenging air compressor, by the pressure rise, subsequent cooling, larger quantity, higher output, single-stage, axial turbine, on the same shaft, depend on the load, scavenging resistance, transmission, to triple the power, swept volume. IV. Give English equivalents to the Russian words and expressions.Увеличить, мощность двигателя, турбонаддув, высокая температура и давление, выхлопные газы, турбокомпрессор, полная нагрузка, частичная нагрузка, импульсный, давление воздуха, зарядка под давлением, центробежный, поршневой, двухступенчатый, осевой, передача, таким же образом, полностью отличающийся, постоянное давление, использовать, приспособиться.V. Form adverbs using suffix –ly and translate into Russian.General, subsequent, main, normal, mechanical, special, complete, high, full, part, quick, sudden, independent, hard, different.VI. Translate sentences paying attention to modal verbs and their equivalents.1. The power output of any engine can be increased by burning more fuel in the cylinder.2. The fuel pumps must have a definite phase relation to the engine crankshaft.3. All engine parts may be removed and replaced easily.4. The worn rings have to be replaced by new ones.5. When the wear reached the allowable level the cylinder had to be rebored and resurfaced.6. To burn more fuel more quantity of air should be supplied.7. These valves were to be pressure tested.VII. Translate from Russian into English.1. Наддув – это процесс, посредством которого цилиндр двигателя заряжается воздухом под давлением.2. Двигатель с наддувом работает на повышенном уровне давления.3. Выхлопные газы приводят в движение турбину.4. Существует два типа двигателей: двигатели с обычным всасыванием и двигатели с наддувом.5. Турбина приводит воздушный компрессор, который увеличивает давление воздуха.6. Турбонаддув бывает импульсный и постоянного давления.7. Преимущество импульсного наддува в том, что двигатель быстро приспосабливается к неожиданным изменениям в нагрузке.VIII. Answer the questions to the text.1. What is a purpose of supercharging?2. What is a turbocharger?3. What’s the difference between normally aspirated engine and turbocharged engine?4. What does the rotation of the rotor depend on?5. What permits the combustion of a larger quantity of fuel?6. What is the result of this combustion?7. What is the disadvantage of the pulse turbocharging?
Вариант 12 I. Read and translate the text “Air Starting System” into Russian.Although all small engines and some fairly large ones used in connection with electric drive are started by electric motors? In connection with electric drive are started by electric motors, the method almost used for starting engines of more than 200 h. p. is by admitting air at 250 to 400 lb. pressure to the cylinders through timed valves. Air for this purpose is provided at any convenient point in the engine room and connected to the starting valves in the cylinder heads. This compressor is of two-stage construction because of the lower pressure to be handled. In some cases the compressor is built into the engine but driven by gears, chairs, or V-belts, and in most installations, especially of large engines, it is independently operated, usually by an electric motor but in some cases by a separate auxiliary engine. Since the maintenance of an adequate supply starting air is vitally essential, the air compressors must be installed in duplicate. If an attached compressor is used, a small independent unit must be provided; if no attached compressor is used, two and sometimes three units are installed. In order to eliminate the possibility of the compressor’s not being started in time during extended periods maneuvering, automatic controls should be installed that will start and stop the compressors in accordance with pressure changes in the air tanks. Although every air starting system uses timed valves in the cylinder heads for admitting air into the cylinders at the right point in the cycle, there are several different methods in use for operating these valves. In every case the air main leading from the tanks is connected to each starting valve, but air is turned into these lines only during the times when the valves are in operation. In one arrangement the valves are operated by cams and levers, the levers being mounted on eccentric fulcrum bearings. Normally the rollers are held up clear of the cams but, when the eccentric bearings are rotated by the control gear, which at the same time operates to open the valve that admits air to the lines leading to the cylinders, the rollers drop onto the cams and the valves open and close in accordance with their timing under the influence of the cams and valve levers. In another arrangement the starting valves in the heads are simply spring-loaded valves that open when air pressure in the valve body exceeds the spring pressure. Air is admitted to the valves at the right times by cam – operated control valves in a control unit at the operating station. In other designs the starting valve is operated by a piston in a cylinder incorporated in the valve body. Air is admitted to this cylinder through a small pipe line leading to a timed pilot valve in the control unit at the operating station. In every case the maneuvering gear is arranged so that air from the tanks is automatically turned on when starting controls are moved to the start position, and cut off when they are moved to the run or stop position.II. Translate into Russian.Almost universally used, 200 h.p., at 250 lb. pressure, timed valves, to discharge air to tanks, at any convenient point, two-stage compressor, to be handled, to be driven by gears, v-belts, chains, a separate engine, an adequate supply of air, to be installed in duplicate, attached compressor, automatic controls, pressure changes, air main, leading to, arrangement, by cams and levers, accentric fulcrum bearing, to hold up clear of the cams, control gear, to drop onto the cam, simple spring-loaded valves, to exceed spring pressure, control unit, operating station, maneuvering gear, to be arranged so that, cut off, turn on, run position, stop position, to be in operation.II. Find English equivalents in the text.Запустить двигатель, для этой цели, удобное место, машинное отделение, конструкция, из-за, более низкое давление, в некоторых случаях, встроен, особенно, работает независимо от двигателя, отдельный, так как, жизненно важный, чтобы, в соответствии с, несмотря на то что, в нужное время, в каждом случае, в обычном состоянии, не касаться, в это же время, в соответствии с, в каждом случае, положение «пуск», «работа», «стоп».III. Complete the sentences.1. This compressor is … unit.2. All the diesel engines are started by …3. The compressors can be driven …4. If an attached compressor is used …5. Automatic controls will start and stop the compressors …6. Timed valves in the cylinder heads are used for …7. The levers are mounted on …8. The air main is connected …9. Spring-loaded valves open when …10. The air starting valve is operated by …11. Air is admitted to …12. Starting controls are moved … and cut off …IV. Read abbreviations in full and translate them into Russian.450 lbs, 2.100 h.p., b.h.p., 28 in, 64 psi, etc., i.e., 30ºC, 100ºF, cu. ft., H.P., LP.V. Translate from Russian into English.1. Откройте нагнетательный клапан на циркуляционном насосе.2. Проверьте давление в ресивере пускового воздуха.3. Откройте вентель на трубопроводе подачи топлива.4. Включите насос охлаждающей воды.5. Проверьте давление масла.6. Прокачайте систему пускового воздуха, чтобы удалить влагу (воду) и смазать все клапаны системы.7. Проверните коленчатый вал двигателя на 1 оборот и убедитесь, что все движущиеся части работают свободно. VI. Ask questions to the following sentences.1. Wear of the piston can be corrected by grinding the piston to a smaller diameter.2. The bearings may pound when the engine is being shut down.3. Oil reaching the piston pin flown out through from three or five drilled passages tospray upon the piston surface.4. One of the two methods of cooling the interior of a piston crown is to circulate lubricating oil through a tube into a chamber formed in the piston crown.5. Thin liners in certain conditions are better than thick ones.
Вариант 13 I. Read and translate the text “ Preparations Prior to Starting the engine”Directions for operation and maintenance of engines can be given with much greater definiteness if intended for a single make or design. Nevertheless some directions are given here, which are of fairly general application. Even where they are not directly applicable, they may be suggestive as to what can be done in the particular case. If the engine has not been operated since an overhaul: 1. Make a thorough inspection to insure that all bolts have been properly set up, and that all devices for preventing the loosening of nuts and pins by vibration have been installed. 2. Examine the piping connections to make sure that they have been properly made up –this is especially important in the case of high-pressure air piping because serious injury to personnel may result if air should be turned into a disconnected pipe.3. Go over the entire engine carefully to find any tools or other objects that may have fallen into the working mechanism.4. With the compression released, jack the engine over by hand several times.5. Check the cooling system: (a) Open the vents at the high point on the cooling system.(b) Fill the engine jacket spaces completely.(c) Be sure that there is an adequate supply of cooling water available before the engineis started.6. Before the engine is closed, examine the lubricating system: (a) See that no rags or other material have been left to plug piping or oil channels.(b) Check the oil sump for the presence of water.(c) Make sure that the oil is at the required level for engine operation. If the engine is being started after a routine securing, the checking does not have to be as extensive as just after an overhaul, but the operator must:1. Make certain that the moving parts of the engine are free.2. See that the cooling system is full of water.3. Check the lubricating oil in the supply sump.4. Operate the hand or stand-by lubricating pump before or while the engine is being jacked – to cover all journals and bearings with a film of oil before the engine is started.5. Clean the filters before starting the engine if they are not cleaned during operation routine.6. Supply oil to all hand lubricated parts.7. Test low-pressure oil alarm.8. Fill the engine fuel-oil system.9. Make sure that no water is present in the fuel.10. Prime the fuel pumps and line through the priming arrangements, and make sure that all air is expelled.11. With the stand-by or hand-operated lubricating oil pump in operation before turningthe engine, jack the engine at least one full turn and disengage the jacking gear.12. Open the sea-injection and overboard valve, and operate stand-by sea-water circulating pump.13. See that there is an adequate flow of water through the cooling system.14. Make sure that the controls are in stop position.15. If engines are of reversing type, set the reverse gear in proper position.II. Give synonyms to the following words.Operation, rapid, application, sufficient, prior, thoroughly, instrument, several, flow, position.III. Give opposites to the following words.To start, improperly, loose, unimportant, disconnect, clean, to open, slowly.IV. Translate the following groups of words.High-pressure air piping; low-pressure oil alarm; air-starting flask; hand-operated lubricating oil pump; stand-by sea-water circulating pump.V. Translate the following sentences into Russian, paying attention to the Nominative with the Infinitive construction.1. Any internal-combustion engine is said to have a four-stroke cycle or a two-stroke cycle, according to whether it receives a working impulse on the piston every other revolution or every revolution.2. After operating in one direction until everything is found to be in good order the engine should be reversed to try out the reversing gear.3. Frames have been known to crack, and the remedy is either to install a new frame or to weld the old one.4. Insufficient lubrication can probably be considered to be the basic reason for all scuffing, but there many reasons for insufficient lubrication, disregarding the most apparent –no oil in the crankcase.5. If an injection valve happens to be in the open position, the air pressure in that cylinder may cause the engine to turn quickly through part of a revolution.6. Correct clearance of adjustable piston-pin bearings may be obtained by removing enough shims to make the bearings bind slightly and then replacing the thinnest possible shim.
Вариант 14 I. Read and translate the text “Inspection Routine” into Russian.Cleanliness is a big asset in the operation of your equipment, for it is our observation that operators in a clean, well- kept engine- room seldom report trouble. Clean and inspect your engines and the auxiliary equipment regularly.DAILY INSPECTION.Under engine is running. Check the level in the clean fuel oil storage tank. The level of the lubricating oil in the sump tank it is running should be to the "engine running full" mark on the gauge. The level when it is not running should never be above the "engine stopped max" mark. Be sure there is sufficient water in the expansion tank of the cooling system. Inspect the sea water supply system. Open the vents on the fresh water system during each watch to relieve the air. Rotate the cleaning handles of the fuel and lubricating oil filters 2 or 3 revolutions every 12 hours. Check the temperature of the oil from the generator bearings. Take readings of all gauges, thermometers and meters at regular intervals. Precede as is recommended in the instruction.PERIODIC INSPECTION.Check the hold down- bolts on the engine and generator.Remove the side covers enclosing the injection pumps and nozzles and make certain that the control racks of each pump move freely. Clean and inspect for wear all external leakage. Check the operation of the overspread governor trip mechanism by pushing the emergency stop button. Be certain that the control racks of the injection pumps move to "no fuel" position,EVERY YEAR OF OPERATION-In addition to the inspection and cleaning as outlined under the preceding paragraphs, the following equipment and engine parts should be included. Automatic timing device-disassemble, clean and inspect the parts. Camshaft Bearings-disassemble and inspect the bearings. Coolers- Fresh Water Jacket- Lubricating Oil- service as outlined in the instructions. Precede as is recommended in the instructions. While the details of the watch routine must necessarily vary with different types of engines, some of the things that are included in a typical routine are as follows:At Least Once Each Hour:1. Turn all injection and exhaust valve stems at least one-half turn to prevent sticking.2. Examine all cam rollers and see that they are free to turn.3. Open vent cocks on top of cylinder covers and air compressors to vent air from jacket spaces. This is particularly necessary when reciprocating water pumps with shifting valves are used.4. Feel air starting pipes close to cylinder covers. Abnormal heating indicates leakingstarting valves.5. Read all thermometers and gauges and record readings.6. Examine cylinder cover joints and air line joints for leaks.7. Open hand hole doors in housing, look for smoke and listen for knocks.8. Examine mechanical lubricators and time their feed.9. Blow water out of spray air bottles.Once Each Watch:1. Clean fuel and lubricating oil strainers.2. Pump bilges.3. Sound and record readings of all oil tanks.4. Wipe down engines and clean engine room thoroughly.Once Each Day:1. Take set of indicator cards.2. Filter one batch of lubricating oil.3. Record fuel and lubricating oil consumption.I. Answer the questions.1. What does daily inspection include?2. What should the engineers pay attention to periodically to have the engine well- operated?3. What should the watch engineer do during the watch?II. Translate the following words and expressions.По крайней мере, при работающем двигателе, спустить, пол оборота, убедиться, трогать, рядом, утечка, показания, продуть, сетка, прокачать тщательно, расход, система подачи, аварийный, механизм аварийного отключения.Ш. Give synonyms to.Rotate, inspect; spray; apply; differ, write; measuring device; supply; search; connections; tube.
Вариант 15 I. Read and translate the text “Maintenance”The condition of the cylinder bore is one of the main factors affecting the operation of a high speed oil engine. When excessive lubricating oil consumption or excessive blow- by is observed the cylinder heads should be removed and the cylinder bores checked for wear. This requires accurate measurements by means of a dial indicator gauge, since the wear is in any case only in thousandths of an inch. When the wear has reached the allowable maximum, the cylinder must be rebored and resurfaced or have a new liner fitted depending on the design. In this connection, maker's instructions should be followed strictly, and great care must be taken, particularly in case of reboring, to ensure that the alignment of the engine is maintained. Some engines particularly highly- rated engines, or engines using unsuitable lubricating oils, may have a tendency to form lacquer deposits on the bores. These lacquer deposits are in nature of a hard varnish, dark brown or black. They prevent the efficient sealing of the cylinder and by causing blow- by lead to excessive wear and increase friction. Any such deposits noticed when the cylinder head is off, should be carefully cleaned away, taking care not to damage the surface of the cylinder bore. On two- stroke engines sludge and carbon deposits may tend, after a period, to foul the ports. Access doors for cleaning, are usually provided, and the ports should be cleaned out to maker's instructions at periods varying from 300 to 1,000 hours according to the design and duty. Periodic examination, particularly at major overhauls, should be made for water leakage. If water leaks into the lubricating oil, there is a serious risk of internal rusting and corrosion with excessive bearing wear and possibly even seizure. Any water leaks should be cured as soon as noticed.II. Answer the following questions. 1. What is one of the main factors affecting the operation of a high- speed oil engine?2. What should be done when the wear has reached the allowable minimum?3. What's the result of using unsuitable lubricating oil?4. What happens if water leaks into the lubricating oil?III. Translate these sentences into Russian, paying special attention to the modal verbs meaning.1. The future P 90 GFC engine will be able to achieve specific fuel consumption of131 g/b.h.p.h. at m.c.p.2. The engine is built as a direct- reversible unit or can be equipped with a hydraulicallyoperated reversing gear.3. Relatively few alterations had to be made with the engine itself.4. This type of engine is to be built in two series, each from four to twelve cylinders.5. A great care should be taken with the design of the upper cylinder liner collar.IV. Translate into English using words and expressions from the text.1. Отложения лака мешают эффективному уплотнению цилиндра.2. Износ, в любом случае, только в тысячных дюйма.3. Если используется неподходящее масло, на стенках цилиндра образуется лакообразный нагар.4. Износ цилиндра можно измерить индикатором с круговой шкалой.5. Любые протечки воды надо устранять как можно быстрее.6. Попадание воды в смазочное масло может привести к ржавлению и коррозии внутри двигателя.V. Give the detailed answers.1. What factors affects the operation of an engine?2. What facts show us that cylinder bore is worn?3. When does reboring become necessary?4. What is the nature of lacquer deposits?5. What factors lead to excessive cylinder wear?6. What deposits way foul the ports?7. How can access to ports be arranged?VII. Retell the text using the key sentences.
Вариант 16 I. Read and translate the text “Location of Troubles”Below are set out the various troubles most likely to be encountered, together with their causes and remedies.Engine Will Not Start1. Not turned fast enough by hand. Try to continue turning after the valve lifter had been dropped. There is no danger of backfiring as with petrol engines. See that the reverse gear is in neutral.2. Loss of compression.a) Sticky valves. Remove and clean the valves spindles, and if necessary, polish with fine emery cloth.b) Insufficient valve clearance. Check the valve clearances.c) Valve seatings not tight. Examine these, and if they show sign of being pitted and are not seated properly, they should be slightly ground in.d) Dry piston after standing. Pour a small quantity of lubricating oil into each air intake.3. Air in the fuel system.Engine Runs Irregularly1. Sticky valves.2. Dirty atomizers.3. Air in the fuel system.4. A fuel- pump delivery valve has stuck up.5. Remove the delivery valve. If the delivery valve is found to be stuck, it will be due to dirt, and carefully cleaning the valve and its guide it should move freely. On no account must emery paper or powder be used.6. Water in the fuel.7. Drain all parts of the fuel system, including the fuel pump and fill up with clean fuel.8. Fuel filter chocked.9. Remove and wash.Engine Knocks.1. Time of injection is incorrect. Check and reset, if necessary.2. A bearing is loose. Examine all bearings and adjust, if necessary.3. A piston is seizing. See that the engine is not being over loaded. Examine the pistons and smooth up any rough parts on the pistons and in the liners.4. Carbon on the pistons hittings the cylinder heads. Decarbonize.Note:If the engine is heard to be knocking at any time it must be slowed down atonce, and if possible stopped and the cause investigated. On no account must it be allowed to continue running, except at a greatly reduced speed. II. Test your comprehension answering the following questions.1. Why cannot the engine start?2. What should you do if the valves are sticky?3. What should be done if you find the piston to be dry?4. What causes the engine to run irregularly?5. Explain how to eliminate the troubles of such running?6. What troubles can water in the fuel cause?III . Translate into English .Поршни заклинило; реверсный механизм, снять крышку, заедание клапана, нагнетательный клапан, почистить, наждачная бумага; фильтр забит; спустить воду (масло); отполировать поверхность; провисать; грязный фильтр, герметичность; несвоевременный впрыск; причина перегрева, потеря давления сжатия; из-за грязи, продолжить работу, сильно изношенный.IV. Give synonyms to the following words.To eliminate, to go on, fast, to fall, to stick, to polish, to check, amount, every, thanks to, to operate, to decrease, to regulate, injection, to tune, to fit.V. Give antonyms to the following words.Slow, to remove, expansion, dirty, necessary, fine, dry, after, to stick up, loose, reduce, rough, head, to stop.VI. Put the verbs into the proper form.1. The piston rings and cylinder liner (to wear) badly.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.VII. 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.3. Frames are sometimes called "crankcases" for the reason that the frame walls enclose the cranks and connecting rods.VIII. 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 17I. Read and translate the text “Location of Troubles”Engine Overheats1. Water circulation defective.See that no foreign matters have collected over the sea intake, in the sea-cock strainer, or in the suction piping. Inspect the valves in the pump and see that there is no grit on the seats and that they are seating properly.2. Time of injection is incorrect.Check and reset, if necessary.Engine Stops of its One Accord1. Dirt in fuel filter or other parts of fuel system. Investigate and clean.2. Water in the fuel.3. Fuel tank is empty.4. A fuel pump delivery valve has stuck up.5. A piston has seized. Dismantle, examine, and smooth up any rough parts on the piston and in the liner.6. The propeller is fouled. Inspect and remove any ropes or other objects which have become entangled.Heating of Stern tube or Intermediate-shaft Bearing1. Misalignment.Check and, if necessary, re-align the engine and intermediate-shaft bearings, if any, from the tail shaft half-coupling.2. Tight stern tube packing.Try slackening the nuts holding the glands slightly. If the gland cannot be eased withoutcausing leakage, the packing has become hard and should be renewed.3. Damaged propeller.Examine the propeller to see that it has not become damaged to such an extent as to throw it appreciably out of balance. If necessary, the propeller must be repaired or renewed.II. Answer the questions.1. What causes the overheating of the engine?2. Why can the engine stop of its own accord?3. What are the reasons of stern tube heating?4. How can you eliminate the above troubles?III. Give English equivalents to Russian words and expressions.Инородные вещества, перегрев, фильтр, гнездо клапана, пустой танк, поршень заклинило, смещение, муфта, нельзя ослабить, не вызывая течь, плотная набивка, циркуляция воды, время впрыска топлива.IV. Give antonyms to the words and make up sentences with both opposites.Dirty, fast, continue, drop, danger, tight; dry, fill up; badly; cylinder head; slow down, reduced speed.V. Translate sentences into English.1. Проверьте уровень масла.2. Отверстия в поршне засорились.3. Поршневые кольца сильно изношены.4. Слегка ослабьте гайки.5. Набивку следует заменить.6. Выровнять шероховатости на втулке цилиндра.7. Перезаправьте топливную систему.
Вариант 18 I. Read and translate the following texts to get some more information about engine designs of different makers.General Information about Burmeister and Wain Engines. The present B. and W. marine engines are all exhaust turbo charged, the power output of which is one- third more than that of the corresponding normally aspirated engines for the same number of revolutions per minute. The reduction of fuel consumption with a turbo charged engine is of 3 per cent. The engine is a single- acting, two- stroke cycle, exhaust poppet- valve type and finds a wide application all over the world. The design is a true crosshead engine, i.e. one in which the crankcase is completely separated from the cylinder. Scavenging air enters the cylinder through a row of ports located in the lower part of the liner. The scavenge air is given a swirling motion. The exhaust gases are expelled through the poppet valve centrally arranged in the cylinder cover. The structural components of the engine type consist of the bedplate, «A» frame and scavenging air receiver. These together form a rigid longitudinal girder which supports the cylinder units. For engines of cast iron construction, vertical mild steel through- bolts are provided. They extend from the top of the cooling water jackets to the bottom of the bed plate cross girders. The crankshaft may be fully- built or semi- built depending on the number of cylinders and torsional vibration characteristics of the system. The main bearing steel shells are lined with white metal, the bearing keeps are of cast steel. The connecting rod bottom-end top-end bearings, also the cross- head shoes, are of cast steel lined with white metal. There are two camshafts. One operates the fuel injection pumps, the other actuates the exhaust valves through cams, rollers, roller guides, push rods and rockers. A fuel injection pump is provided for each cylinder and it's cam- operated through a roller and roller guide from a camshaft. The cylinder covers are made of chrome – molybdenum cast steel and are bolted to the cooling water jackets. The liners are of very simple design made of alloy cast iron. Two fuel valves, a starting valve, a safety and exhaust valves are arranged in the cylinder cover. The cylinder covers, c. liners and exhaust valves are fresh water cooled. The pistons are of a simple design with crowns of chrome- molybdenum cast steel and skirts of cast iron. The pistons are oil- cooled from the forced lubrication system. The B. and W. turborchavging system for two-stroke cycle engines is a flunctuating pressure system.II. Answer the questions.1. What is the power output of the pressure- charged engines?2. What are the main particulars of the B. and W. design?3. In what way are the cylinders scavenged?4. How is the fuel injection pump operated?5. What material are the cylinder covers made of?6. What valves are arranged in the cylinder cover?7. What pistons are used in the engine?III. Translate the following words and expressions into Russian.Exhaust – turbocharged, normally aspirated engine, reduction of fuel consumption, a single – acting, exhaust poppet valve, cross head; a swirling motion, to expell, centrally arranged, a bedplate, a frame, rigid longitudinal girder, steel through bolts, to provide, fully- built; semi-built; torsional vibration, to operate, to actuate cylinder cover, cylinder head, the crown, the skirt, a flunctuating pressure system. IV. Form nouns from the following verbs.To inject, to arrange, to vibrate, to connect, to operate, to revolve, to reduce, to apply, to locate, to separate; to receive, to support, to cool, to heat, to operate, to inject, to actuate;to press, to measure.V. Translate sentences into Russian. Pay attention to the Ving translation.1. Fuel delivery is regulated by varying the effective stroke- volume of the pump.2. The second row of scavenging ports is closed by mechanically driven valves.3. When operating the pistons move simultaneously either towards each other or awayfrom each other.4. No essential results having been obtained, the scientists had to carry out some moreexperiments.5. Manoeuvring is carried out by a single lever for starting and reversing, the second leverbeing provided for controlling the speed of the engine by adjusting the fuel supply.6. In engines having more than six cylinders the crankshaft is built up in two parts.VI. Give English equivalents to Russian words.Система продувки, продольная балка, рамовый подшипник, коренной подшипник,башмак крейцкопфа, составной каленчатый вал, расходный танк, головка поршня крейц-копфного двигателя, юбка (верхняя часть) поршня, сплав, чугун, литая сталь, прокован-ная сталь, сварочная сталь, смазка под давлением, пульсирующее давление, в два раза больше чем, широко использоваться, расположенный в центре.VII . Translate into English .1. Турбонаддув увеличивает мощность двигателя.2. Такие двигатели расходуют меньше топлива.3. В двигателе крейцкопфного типа картер полностью отделен от цилиндра.4. Подъемный клапан расположен в крышке цилиндра.5. Один из кулачковых валов регулирует работу выхлопных клапанов через систему кулачков, роликов, их направляющих, толкателей и коромысел.VIII. Ask as many questions as you can.The New Four-stroke Diesel Engine Type 65/65 is a Common Development from M.A.N. and Sulzer Brothers Design Features.
Вариант 19 I. Read and translate the text into Russian.The engine can burn heavy fuel and will be built as a reversible and nonreversible prime mover. The engine frame consists of a crankcase of fabricated design and cast cylinder blocks. The demand that the cast components must be of limited weight and volume to simplify the casting procedure and that the crankcase must be built in one-piece had a great influence on the design.Crankcase.The main bearings of the crankshaft are located in the cast steel cross girders which are welded into crankcase. These results in a favourable flow of the ignition forces. By using suitable devices, the dismantling and fitting of the bearing can be carried out easily. The camshaft drive which is situated on the coupling side, is integrated into the crankcase. The gear wheels have a long service life due to the shift and vibration-free seatings. The torsional vibration damper fitted on the crankshaft on the opposite side of the coupling is located within the crankcase. Large openings in the crankcase guarantee good accessibility to the moving parts and bearings.Cylinder block.The row of cylinder blocks made of cast iron are very resistant to corrosion. For all cylinder numbers the rows of cylinder blocks are of three sections with end pieces for two cylinders each at the aft and forward side. The rods which are parallel to the cylinder axis relieve the castings of tensile stresses. The cylinder blocks and sections are built as stiff brackets, so that the turbochargers can be mounted on the coupling side or on its opposite.Technical data are as follows:Bore …………………………….. 650 mmStroke …………………………… 650 mmPiston displacement …………….. 216 lit/cylOutput ……………………………1600 bhp/cyl (1180 kw/cyl)Speed ……………………………. 375 rpmMean piston speed ……………… 8,12 m/sMean effective piston pressure … 17, 8 kg/cm2 (17, 5 bar).II. Translate words and words – expressions into Russian.Four- stroke diesel engine, design features to burn heavy fuel, a reversible prime- mover, engine frame crankcase, limited weight and volume, main bearing, cast steel cross girders, dismantling of the bearings, camshaft drive, torsional vibration damper, cylinder axis, tensile stresses, stiff brackets, accessibility to moving parts, gear wheel.III . Translate into English .Вес и объем, привод распредвала, гарантировать доступ, цельный картер, чугунная балка, крутильные колебания, среднеэффективное давление газов, диаметр цилиндра, выходная мощность, гарантировать доступ, четырехтактный двигатель, установка, ось цилиндра, разборка.IV. Say in English.Bhp/cyl; kw /cyl; r.m.p., m /c, m.m., kg/cm2, h.p., H.P, L.P, V- form.V. Ask questions to the sentences.1. The fuel ignited because of the high temperature of the compressed air.2. To settle the problem of the engine weight they improved some of its parts.3. The charge- air compressor and exhaust gas turbine are combined to form supercharging unit.4. The engine is offered with 6, 8&9 cylinders in line and 12&16 cylinders in V- form.5. The cylinder head carries two inlet and exhaust valves.6. The rods relieve the castings of tensile stresses.VI. Give nouns from the words and translate them.Reversible, favourable, suitable, accessible, available, reliable, movable.VII. Translate into Russian.1. The rods were introduced to relieve the welded structures of the large ignition forces reaching several hundred tons in large engines.2. To improve running of the piston rings and reduce wear the pistons run in soft-nitrited cylinder liners.3. The cams with double contour allow the camshaft to be moved axially by hydraulic servo without the need to lift tappets (палец).4. Most of the components are readily (without any trouble) accessible and special purpose handling equipment is available to reduce overhaul time.5. The row of cylinder blocks made of cast iron are very resistant to corrosion.VIII . Translate into English .1. Цилиндровая втулка состоит из двух частей.2. В конструкции поршня предусмотрено охлаждение смазочным маслом.3. Крышка цилиндра оснащена двумя впускными и двумя выпускными клапанами.4. Клапанами управляют кулачки со спаренными коромыслами.5. У этого двигателя необычная конструкция.6. Для интенсивного охлаждения просверлены отверстия.IX. Answer the questions.1. What fuel can this fuel burn?2. What are the main technical data of the engine?3. What demand had a great influence on the design?4. What location of main bearings results in a favourable flow of the ignition forces?5. Where is the camshaft drive situated?
Вариант 20 I. Read and translatethe text “Akasaka 8 U 50 Engine”The engine is built to operate at such a speed that it doesn't require to be coupled to a reduction gearbox. The Akasaka 8U50 engine is a trunk piston medium- speed unit which is produced in eight in- line cylinders and develops its rating of 813 b.h.p./cylinder at 340 rev/min. This machine is a development of Akasaka's earlier 6U50 machine which, though of less cylinders, was rated at 917 bhp/cylinder at 340 rev/min. The Akasaka 8U50 engine is a four- stroke machine with two inlet and two exhaust valves which are actuated by rockers. The machine operates on low- grade heavy fuel and, because of that, the exhaust valve seats are arranged for fresh water cooling. The pistons are of the built- up type with an alloy steel crown and cast iron skirt; cooling is by system lubricating oil. The entire construction of the engine including the bed plate, cylinder block and cylinder covers, is of cast iron. The bed plate is cast in two pieces and clamped together by horizontal stay bolts at the centre of No, 6 cylinder. The crankshaft is of the solid type, balance weights are fitted on each crank web. It is a turbo chargers are mounted one on either end of the engine.II. Translate the English phrases.To operate at a speed of, is not coupled to, a trunk piston engine; to develop its rating of; entire construction, build up type; high grade fuel, low grade fuel, actuated by rockers; a development of an earlier design, to be made of cast iron, is mounted on; to be a turbo-charged engine.III. Form a comparative degree of the following adjectives.Small, much, early, late, good, little, low, high, heavy, comfortable, complex, effective.IV. Give synonyms to.Machine, velosity, pair, rating, emission, head, to install, to fix, decrease, to work out, to be connected, to run, to be designed for, comprise, whole, everyV. Say in English.30 0C, 15 m3, 340 rev/min, 810 bhp/cyl., 120 kg/cm2.VI. Ask questions to.1. This engine operates at the speeds of 210 to 110 rev/min.2. Air pressure of 7 kg/cm2 is applied to the cylinder during low load conditions.3. Symmetrical cams were installed for fuel pumps.4. Long stay bolts will secure the cylinder block to the entablature.VII . Translate into English .1. Масло подается к рамовым подшипникам.2. Мощность этого двигателя 917 л.с. при 340 об/мин, не смотря на меньшее количество цилиндров.3. Этот двигатель может работать на топливе низкого качества.4. Головка поршня из стального сплава, а юбка поршня – чугунная.5. На каждом плече кривошипа стоит противовес.VIII. Answer the questions.1. What are the peculiarities of Akasaka engine design?2. What's its rating?3. What type of engine does it concern?4. What fuel can it operate?5. What can you say about engine piston?6. Where are balance weights fitted?
Вариант 21
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I. Read and translate the text«Types of Diesel Engines». Check your comprehension by answering the questions.
Two-cycle and four-cycle diesel engines may be divided, according to structural arrangement, as follows: trunk-piston type, crosshead type, single-acting, double-acting, opposed-piston.
Trunk-piston and Crosshead Types
In the trunk-piston type the piston is attached to the crank by means of a connecting rod. Connection of the upper end of the rod to the piston is made by means of the piston pin, while the lower end is attached to the crankpin by means of a bearing known as the crankpin box. The horizontal component of the downward thrust of the piston, when it drives the crank, is taken by the piston and results in a side pressure against the wall of the cylinder. To provide adequate bearing so that this side pressure will have a low unit value, the piston is provided with an extended skirt, or trunk, from which this method of construction gets its name. This construction has the advantages that it reduces engine height and is cheaper than crosshead construction. It is universally used for small engines and in some cases for engines of quite large power. The crosshead type is usually confined to large engines. The piston is connected to the crosshead by a piston rod and the crosshead is in turn connected to the crankpin by a connecting rod. This construction has the advantage of relieving the piston and cylinder wall of side thrust and in the four-cycle engine permits to use a short piston. In the case of a two-cycle engine the extended piston skirt is still required in order to keep the exhaust and scavenging ports closed during the upstroke of the piston. This construction is penalized by the extra height required to make room for the crosshead and piston rod.
II. Answer the questions:
1. How is the piston attached to the upper and lower ends of the connecting rod in the trunk-piston engine?
2. What advantages does this engine have?
3. What advantage does the crosshead type engine have?
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