任务四冷却系统和润滑系统.pptx

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1、2022/12/20汽车专业英语 边浩毅黄国潮 冯谣 高等职业教育高等职业教育“十三五十三五”规划教材规划教材 主 编副 主 编2022/12/20四冲程发动机基础知识介绍发动机构造认识燃油直喷系统发动机冷却系统和润滑系统认识发动机点火系统和起动系统认识任务一任务二任务三任务四任务五任务六任务七任务八底盘构造认识汽车检测设备认识KT600汽车诊断系统任务九汽车市场调查分析进出口交易的一般流程来人来电购车接待汽车产品配置介绍汽车保险办理汽车销售礼仪任务十任务十一任务十二任务十三任务十四任务十五任务十六汽车产品售后服务出国手续办理 任务四 发动机冷却系统和润滑系统认识Brief Introduct

2、ionWord ListText learning-exampleProper Names1234Translation of difficult sentence5Practical Reading6 Brief Introduction1.thermostat mstt n.节温器，温度自动调节器2.fan fn n.风扇3.transfer trnsf;trns-;-nz-vt.转移，传递4.copper kp n.铜，铜制品5.rust rst n.铁锈6.centrifugal,sentrfjug()l adj.离心的，离心力的7.dissipate dspet v.驱散，消散8.i

3、dle ad()l adj.空闲的，懒惰的，怠速的9.objective bdektv n.目标，目的10.antifreeze ntfriz n.防冻剂11.vessel ves()l n.容器，器皿 Word List2022/12/20 Word List12.climate klamt n.气候，风土13.inhibitor nhbt n.抑制剂14.corrosion kr()n n.腐蚀15.generous den()rs adj.慷慨的，大方的，大量的16.destruction dstrk()n n.破坏，毁灭17.friction frk()n n.摩擦，摩擦力18.lub

4、ricant lubrk()nt n.滑润剂19.task/tsk n.任务，作业20.abrasive bresv adj.研磨的 n.研磨剂21.viscosity vskst n.粘度22.accumulation kjumjle()n n.积聚，堆积物2022/12/20 Word List23.detergency dtdns adj.清净性24.varnish vn n.漆膜，清漆25.lacquer lk n.漆膜，涂膜26.substance sbst()ns n.物质，实质 27.regularly rjlli adv.有规律地，有规则地 28.screen skrin n.

5、筛子 29.diluent dljnt n.稀释液，冲淡剂30.acid sd n.酸 Text learning-exampleThe power train carries powerA cooling system of some kind is necessary in any internal combustion engine.The cooling system of a water-cooled engine consists of the engine water jacket,thermostat,water pump,radiator,radiator cap,fan,f

6、an drive belt and necessary hoses.Engine Cooling SystemEngine Cooling System2022/12/20Text learning-example In an automobile engine,heat flows or transfers from the iron or aluminum cylinder to the cooling water,and from the coolant to the copper or aluminum radiator.Heat transferHeat transfer2022/1

7、2/20 Automobile engine water pumps are of many designs,but most are the centrifugal type.Sometimes the fan is installed on the water pump shaft.Text learning-exampleCooling System PumpCooling System Pump2022/12/20The radiator is a device designed to dissipate the heat that the coolant has absorbed f

8、rom the engine.It is constructed to hold a large amount of water in tubes or other passages which provide a large area in contact with the atmosphere.Text learning-exampleRadiator Radiator 2022/12/20 The radiator cap is designed to seal the cooling system so that it operates under some pressure.This

9、 improves cooling efficiency and prevents evaporation of the coolant.Text learning-exampleRadiator CapRadiator Cap2022/12/20 The fan is designed to draw cooling air through the radiator core.This is necessary at low speeds or when the engine is idling,since there is not enough air motion under those

10、 conditions to provide adequate cooling.Text learning-exampleCooling Fan Cooling Fan 2022/12/20 Automotive internal combustion engines operate more efficiently when a high temperature is maintained within narrow limits.To attain this objective,a thermostat is inserted in the cooling system.In operat

11、ion,the thermostat is designed to close off the flow of water from engine to radiator until the engine has reached the desired operating temperature.Text learning-exampleThermostatThermostat2022/12/20When water freezes,it expands approximately nine percent in volume.Because of this great rate expans

12、ion,it will break or serious distort the shape of the vessel in which it is contained.Because of this characteristic,it is necessary to use a nonfreezing solution in the cooling system of water-cooled engines operated in climates where the temperature is below the freezing point of water.Text learni

13、ng-exampleAntifreeze SolutionAntifreeze Solution2022/12/20 Excessive friction in the engine,however,would mean rapid destruction.We cannot eliminate internal friction,but we can reduce it to a controllable degree by the use of friction reducing lubricants.Text learning-example Lubricating System Lub

14、ricating System2022/12/20Text learning-exampleOil PumpOil PumpThe pumps used to circulate the oil are of the positive displacement type in several designs.Since these pumps handle oil,they are well lubricated at all times and do not suffer from excessive wear.Most cases of lost oil pressure are due

15、to excessive clearance in the bearings of the engine rather than worn oil pumps.Another reason for lack of oil pressure is stoppage in the oil pump supply line or screen.A typical cause is the accumulation of sludge in a screen.2022/12/20Text learning-exampleOil sludgeOil sludge Sludge is a mixture

16、of water,oil,dirt and other products of combustion.It is most likely to form in an engine that seldom reaches a satisfactory operating temperature.Slow speed,stop-and-go operation means that the engine seldom gets hot enough to drive the water and vapor out of the crankcase.Sludge formation can be h

17、eld to a minimum by using the correct cooling system thermostat to maintain a high engine operating temperature.Using engines oils of high detergency and making frequent changes of oil and filter are necessary.Adequate crankcase ventilation is also important.2022/12/20Text learning-example Oil Filte

18、r Oil FilterOil filter is placed in the engine oil system to remove dirt and abrasives from the oil.Diluents,such as gasoline and acids,are not removed.However,by removing the solid materials,the possibility of acids forming is reduced,and the rate of wear of engine parts is greatly reduced.Oil filt

19、ers installed on modern passenger car engines are full-flow type;all oil passes through the filter before it reaches the bearings.However,in the event the filter becomes clogged or obstructed,a bypass valve is provided so that oil will continue to reach the bearings.Proper Names1.cooling system 冷却系2

20、.lubricating system 润滑系 3.radiator cap 散热器盖4.radiator core 散热器芯5.fan blade 风扇叶片6.positive displacement type 容积式7.oil sludge 油泥8.crankcase ventilation 曲轴箱通风9.break down 分解10.pour point depressant 降凝剂11.detergent-dispersant 清净分散剂12.foam inhibitor 抗泡剂13.oxidation inhibitor 抗氧剂14.viscosity index improve

21、r 粘度指数改进剂15.antiwear additive 抗磨添加剂Translation of difficult sentence1.In an automobile engine,heat flows or transfers from the iron or aluminum cylinder to the cooling water,and from the coolant to the copper or aluminum radiator.翻译：在汽车发动机里面，铁或铝制的气缸将热量传导到冷却水，再由冷却水将热量传递到铜或铝制的散热器中。2.It is constructed

22、to hold a large amount of water in tubes or other passages which provide a large area in contact with the atmosphere.翻译：结构上，散热器要有能容纳大量水的管道，这些管道能提供很大的散热面积，便于与空气接触。语法：which引导定语从句，修饰tubes or passages。3.In operation,the thermostat is designed to close off the flow of water from engine to radiator until

23、the engine has reached the desired operating temperature.翻译：工作时，在发动机还未达到合适的工作温度前，节温器切断从发动机水套流向散热器的水路。语法：until the engine has reached the desired operating temperature引导时间状语从句。2022/12/20Translation of difficult sentence4.Because of this characteristic,it is necessary to use a nonfreezing solution in

24、the cooling system of water-cooled engines operated in climates where the temperature is below the freezing point of water.翻译：由于冷却水会在低温下冻结，所以，水冷式发动机在水的凝固点以下的气候条件下运行时，需要向冷却系统中加入防冻液。语法：Because of后接短语表原因。it is necessary to use是it作形式主语，为了避免全句的头重脚轻。真正主语是to不定式，本句亦是To useis necessary。5.We cannot eliminate

25、internal friction,but we can reduce it to a controllable degree by the use of friction reducing lubricants.翻译：虽然不能消除发动机内的摩擦，但可以通过使用减摩润滑剂，将摩擦减小到一定的程度。2022/12/20Translation of difficult sentence6.Most cases of lost oil pressure are due to excessive clearance in the bearings of the engine rather than w

26、orn oil pumps.翻译：多数情况下，机油压力不足是由于发动机内轴承间隙过大造成的，而不仅仅是由于机油泵磨损造成的。7.Slow speed,stop-and-go operation means that the engine seldom gets hot enough to drive the water and vapor out of the crankcase.翻译：低速、停停开开等工况意味着发动机温度不高，不能将曲轴箱内的水和水蒸汽排出。语法：that引导的从句作谓语mean的宾语。2022/12/20Practical ReadingAir Conditioning S

27、ystemNot only do we depend on our cars to get us where we want to go,we also depend on them to get us there without discomfort.We expect the heater to keep us warm when its cold outside,and the air conditioning system to keep us cool when its hot.Despite its relatively small size,the cooling system

28、has to deal with an enormous amount of heat to protect the engine from friction and the heat of combustion.The cooling system has to remove a lot of heat per minute.This is more than we need to heat a large home in cold weather.Its good to know that some of this heat can be put to the useful purpose

29、 of keeping us warm.Air conditioning makes driving much more comfortable in hot weather.Your cars air conditioner cleans and dehumidifies,the outside air entering your car.It also has the task of keeping the air at the temperature you select.The job of the air conditioning system is really to remove the heat that makes us uncomfortable,and return the air to the cars interior in a un-heated condition.Air conditioning,or cooling,is really a process of removing heat from an object.2022/12/20 THANK YOU