9.润滑系(双语)
润滑名词解释（精制知识）
润滑名词解释（精制知识）润滑类(1)润滑(Lubrication)用润滑剂减少两摩擦表面之间的摩擦和磨损或其它形式的表面破坏。
(2)润滑类型(Types of Lubrication)润滑剂在两表面间存在的条件和状态。
(3)流体润滑(Fluid Lubrication) 作相对运动的两固体表面被具有体积粘度特性的流体润滑剂完全隔开时的润滑状态。
(4)混合润滑(Mixed Lubrication) 在两固体的摩擦表面之间同时存在着干摩擦、边界润滑或流体润滑的混合状态下的润滑状态。
(5)固体润滑(Solid Lubrication) 作相对运动的两固体表面之间被粉末状或薄膜状固体润滑剂隔开时的润滑状态。
(6)边界润滑(Boundary Lubrication) 作相对运动的两固体表面之间的摩擦磨损特性取决于两表面的特性和润滑剂与表面间的相互作用及所生成边界膜的性质的润滑状态。
(7)极压润滑(Extreme-pressure Lubrication) 作相对运动的两固体表面之间的摩擦磨损特性取决于润滑剂在重载下与摩擦表面产生化学反应的润滑状态。
(8)流体动压润滑(Hydrodynamic Lubrication) 依靠运动副滑动表面的形状在相对运动时形成一层具有足够压力的流体膜，从而将两表面分隔开的润滑状态。
又称流体动力润滑。
(9)流体静压润滑(Hydrostatic Lubrication) 依靠外部的供油系统将具有一定压力的润滑剂供送到支承中，在支承油腔内形成具有足够压力的润滑油膜将两表面分隔开的润滑状态。
又称流体静力润滑。
(10) 弹性流体动压润滑(Elasto-hydrodynamic Lubrication) 相对运动两表面之间的摩擦和流体润滑剂膜的厚度取决于表面弹性形变以及润滑剂在表面接触区的流变特性的润滑状态。
又称弹性流体静力润滑。
(11)气体润滑(Gas Lubrication)相对运动两表面被气体润滑剂分隔开的润滑。
汽车英语——发动机润滑系
Lesson FiveEngine Lubrication SystemUseful sentences:1.An automobile could not move itself without the aid of friction.没有摩擦的作用，汽车就不能开动。
2.Too much friction in the engine would mean rapid destruction.过多的发动机摩擦也意味着发动机的快速毁坏。
3.Friction be reduced by the use of lubricating oil。
用润滑油可以减少摩擦。
4.Lubricating oil has several functions in the lubrication system.润滑油在润滑系中有好几个功能。
5.The oil lubricates the moving parts and forms a protective coating on the metal surface.机油可润滑运动部件并在金属表面形成保护膜。
6.The oil absorbs or carries the heat away from the engine parts.机油吸收并带走发动机部件产生的热量。
7.The oil washed off dirt away from the engine parts.机油冲洗走发动机部件上的污垢。
8.The oil forms a good seal between piston rings and cylinder wall.机油在活塞环和气缸壁之间形成密封油膜。
9.The lubrication system also contains other mechanical parts such as the oil pump, the oilfilter, the oil pressure relief valve, etc.润滑系还包括其他机械部件如油泵、机油滤清器、机油减压阀等。
U5 THE LUBRICATION SYSTEM润滑系 附扩展第5篇
UNIT 5 THE LUBRICATION SYSTEM学习目标:1.掌握润滑系相关的专业术语、词汇。
2.能对润滑系相关的资料进行中英文互译。
3.能进行相关内容的阅读和翻译。
TEXT A THE LUBRICATION SYSTEM1. Lubrication PrinciplesReducing friction to minimize wear and loss of power is the primary job a lubrication system must perform[1]. Residual oil on engine parts also provides lubrication for engine start-up.The engine oil forms a seal between the pistons, rings, and cylinders. It also helps to cool engine parts. Without the cleaning acting of the lubricating system, carbon and varnish build up would be excessive. The engine oil also absorbs the shock and dampens the noise of moving parts.How successful the lubrication system is in performing all these functions depends on a number of factors and conditions. There must be an adequate supply of good-quality lubricant delivered to all moving engine parts under sufficient pressure to provide hydrodynamic lubrication for rotating parts and oil adhesion to surface subject to sliding friction.2. Parts of the Pressure-Lubrication System2.1 Oil PanThe oil pan bolts under the engine block, where it seals off the bottom of engine. Shaped like a trough, this sheet-metal pan serves as the reservoir for about 5 quarts of oil. As oil flows from the engine, it drains downward into the oil pan. The oil pump sucks oil from the lowest part of the oil pan, the oil sump. Many oil pans have baffles, which are thin metal partitions. These keep the oil in the sump when the car corners hard or brakes suddenly. A drain plug at the bottom of the sump allows oil to be drained from the engine. The oil-pan gasket fits between the oil pan and the bottom of the engine block.In most engines, the oil circulates in the engine, and then returns to the pan. It stays in the oil pan until drawn back into the engine by the oil pump. During operation, the sump usually holds 2 to 3 quarts of oil. The rest of the oil moves through the passageways of the lubrication system. With the engine off, the pan holds about four quarts of oil. The fifth quart is in the oil filter. Because a pool of oil always rests in the sump, the type of lubrication system is called a wet-sump oiling system.A dry-sump oil system is used in many racing engines. This system has a separate storage tank for the oil. A second oil pump draws oil from the oil pan as the oil drains from the engine. As a result, a dry-sump system can circulate more oil through the engine than a wet-sump system.2.2 Oil PumpThere are two general types of automotive-engine lubricating-system oil pumps, gear and rotor. The gear-type oil pump uses a pair of gears. As they rotate, the spaces between the teeth are filled with oil from the oil inlet. Then, when the gears mesh, the oil is forced out through the oil outlet.The rotor-type oil pump has an inner and an outer rotor. The inner rotor is driven and turns the outer rotor. The spaces between the rotor lobes become filled with oil. When the lobes of the inner rotor move into the spaces in the outer rotor, the oil is squeezed out through the outlet.Oil pumps are usually driven from the engine camshaft by the same spiral gear that drives the ignition distributor. The oil intake for the oil pump is attached to a float in some engines. This floating intake takes oil only from the top of the oil in the oil pan. Since dirt particles sink, the top oil is the cleanest.2.3 Oil FilterAll automotive-engine lubricating systems have an oil filter（Figure5-1）. Oil circulates through this filter. In the filter, an element of filtering material traps particles of foreign material. This helps to keep the engine oil clean and to prevent particles from entering the engine.Oil filters are of two types. Those that filter part of the oil from the oil pump are caller bypass oil filters. Those that filter all the oil from the oil pump are caller full-flow oil filters. Some turbocharged diesel engines have both types of filter.Figure 5-1 oil filterFull-flow filters have a spring-loaded bypass valve. It protects the engine from oil starvation if the filter becomes clogged. If this happens, the valve is opened by the increased pressure from the pump trying to push oil through the filter. With the valve open, oil bypasses the filter. However, before this happens, the filter should be changed. The oil circulating with the valve open is not filtered and engine damage could result.3. Engine LubricationAn internal combustion engine would not run for even a few minutes if the moving parts were allowed to make metal-to-metal contact. The heat generated due to the tremendous amounts of friction would melt the metals, leading to the destruction of the engine[2]. To prevent this, all moving parts ride on a thin film of oil that is pumped between all the moving parts of the engine. Once between the moving parts, the oil serves two purposes. One purpose is to lubricate the bearing surfaces. The other purpose is to cool the bearings by absorbing the friction-generated heat. The flow of oil to the moving parts is accomplished by the engine’s internal lubricating system. Figure 5-2 shows a engine’s lube oil circuit schematic.Figure 5-2 lube oil circuit schematicThe oil pump is of the gear type, consisting essentially of two gears in mesh and requires no attention or adjustment. It is housed in the sump, being driven by a shaft and skew gearing from the camshaft.Oil from the sump is delivered at full pressure to all main bearings and camshaft bearings through gallery pipes and drillings in the cylinder block. The big-end bearings are fed from the main bearings via passages in the crankshaft.Lubrication for the timing chain is supplied an two points, by a feed from the front camshaft bearing into the periphery of the camshaft chain wheel and also by oil fed through the hollow shaft on which the timing chain jockey pulley is mounted arid thence through holes in the circumference of the jockey pulley.The inlet and exhaust rocker shafts are hollow, the inlet shaft being fed with oil from the rear of the main gallery pipe via an external pipeline, whilst that for the exhaust rockers and inlet followers is supplied via drillings from the center camshaft bearings. Each rocker and follower receives its oil through small holes drilled in the rocker shafts and in turn they are themselves also drilled, so that the oil finds its way through them and thence out again to lubricate the points of contact with the valves, push-rods and camshaft[3]. The distributor drive shaft is lubricated with oil fed from the exhaust rocker shaft via a hollow bolt.Surplus oil from the inlet valve gear returns through the cylinder casting and that from the exhaust valve gear direct to the sump.4. Lubrication OilsMotor oils for automobile engines fall into two basic categories: petroleum-based oils and synthetic oils. Petroleum-based oils, however, contain a variety of additives; so in fact they, too, are partly synthetic.The oil lubricates moving parts in the engine to minimize wear. Clearances between moving parts are filled with oil. The parts move on the layers of oil to minimize wear. Parts moving on layers of oil requirecomparatively little power to move them. The oil minimizes frictionhorsepower.The circulating oil helps cool the engine. As the oil moves through the engine, the oil gets hot. Then, when it drops down into the oil pan, which is cooler, the oil gives up this heat. So the oil is continually removing heat from the engine.The oil also helps absorb shock loads. When the power stroke starts, a force of as much as 4000 pounds is suddenly imposed on the rod and main bearings[4]. The layers of oil in the bearing clearances resist 〞squeezing out〞, acting as cushions to absorb the sudden load.The oil helps form a gastight seal between piston rings and cylinder walls. In forming this, the oil helps to reduce blowby.The oil acts as a cleaning agent. As it circulates through the engine, the oil picks up particles of metal and carbon and carries them back down into the oil pan. Larger particles fall to bottom of the oil pan. Smaller particles are filtered out by the oil filter.NEW WORDSl ubrication ['lu:bri'keiʃən ] n. 润滑；润滑作用；润滑油principle ['prinsəpl] n. 原理，原则；主义，道义；本质，本义；根源，源泉residual [ri'zidjuəl,ri'zidʒuəl] n. 剩余；残渣adj. 剩余的；残留的varnish ['vɑ:niʃ] n. 虚饰；光泽面；亮光漆，清漆vt. 装饰，粉饰；在…上涂清漆；使…有光泽buildup ['bildʌp] n. 组合；增强；发展；形成；树立名誉quart [kwɔ:t] n. 夸脱（容量单位，等于1／4加仑或2品脱）；一夸脱的容器excessive [ik'sesiv] adj. 过多的，太大的，过分的；过度的，极度的，放纵的dampen ['dæmpən] vt. 使降低；减少；抑制；使扫兴；使沮丧，使消沉，给…泼冷水；潮湿，弄湿，沾湿，使湿润partition [pɑ:'tiʃən] n. 分开；隔开；划分；分配隔开物；隔墙；隔板；区分线；区分物部分；隔开部分；隔开的房间gum [ɡʌm] n.树胶；橡皮；口香糖vt. 使…有粘性；用胶粘，涂以树胶rough [trɔf,trɔ:f] n. 槽，饲料槽，和面槽；洗槽，水槽；槽形物baffle ['bæfl] vt. 使…困惑；使…受挫折；用挡板控制vi. 做徒劳挣扎n. 挡板；困惑sump [sʌmp] n. 油底壳，机油箱；污水坑；水坑vi. 挖深（渠道，井筒等）turbocharge ['tə:bəutʃɑ:dʒ] vt. 用涡轮给增压clog [klɔɡ] vt.阻塞，堵塞(管子、道路等)；障碍，妨碍，阻碍；挤满，填满vi.发生阻碍；堵塞，堵住；塞满：粘住，粘在一起；凝成一块n.障碍物；阻碍；妨碍porosity [pɔ:'rɔsiti, pəu'rɔsiti] n. 多孔性；有孔性；多孔的东西；多孔物质；多孔部分；多孔结构periphery [pə'rifəri] n.周界线(尤指圆周)；周边；外围；周围；边缘；界限外表面(尤指圆体的外面)，外部；次要部分；无关紧要部分，边缘科学synthetic [sin'θetik] adj. 综合的(相对于analytic) ；合成的，人造的；合成燃料的n. 合成物；合成纤维；合成剂antiscuff [ʌnti'skʌf] n.磨损overhaul ['əuvə'hɔ:l,'əuvəhɔ:l] vt. 解体检修，拆修，大修：彻底检查，仔细检验：全面修订；彻底革新(或改革)：n.拆修，大修全面检查；详细检验全面修订；底革新(或改革)neutralize ['nju:trəlaiz] vt. 抵销；使…中和；使…无效；使…中立vi. 中和；中立化；变无效agitation ['ædʒiteiʃən] n. 激动，兴奋，煽动，搅动PHRASES AND EXPRESSIONSoil Pan油底壳dry-sump 干油底壳wet-sump 湿油底壳pickup tube机油吸油管filter screen滤网full-flow filtering system全流式滤清系统pressure-relief valve 安全阀泄压阀gear type oil pump齿轮式机油泵jockey pulley张紧轮，导向轮corrosion inhibitor 防腐剂detergent-dispersant 清洁分散剂viscosity index 粘度指数foam inhibitor泡沫抑制剂KEY VOCABULARYabsorb[əb'sɔ:b, əb 'zɔ:b]vt.1.吸收；吸引；承受；理解；使…全神贯注:Blotting paper absorbs ink. .吸墨水纸吸墨水。
润滑系的概述及主要部件
润滑系概述一、润滑系的作用：1、润滑作用：将机油不断地供给各零件的摩擦表面，减少零件的摩擦和磨损。
2、清洗作用：清除摩擦表面上的磨屑等杂质。
3、冷却作用：气缸壁上形成的油膜可冷却摩擦表面。
4、密封作用：在运动零件之间、气缸壁上形成的油膜形成油膜可以提高密封性，防止漏气和漏油。
5、防锈作用：在零件表面形成油膜，防止零件生锈。
6、液压作用：利用润滑油作液压油。
7、缓冲作用：在运动零件表面形成油膜，吸收冲击减小振动。
二、润滑方式：1.压力润滑以一定的压力将油输送到摩擦表面间隙中。
适于负荷和转速较大机件，如曲轴主轴承、连杆轴承、凸轮轴承及摇臂轴等。
2.飞溅润滑靠运动零件溅起的细小油滴落在摩擦表面.适用于负荷较轻和速度较小或露在外面的机件。
如气缸壁、配气机构的凸轮、挺杆3.定期加注润滑：如水泵、发电机轴承等。
三、润滑系的压力汽油机：0.2MPa~0.4MPa。
柴油机： 0.3MPa~0.6MPa。
四、润滑系组成•机油泵•集滤器•粗滤清器•细滤清器•限压阀•旁通阀•机油盘•压力与温度感传器•压力表和量油尺•机油散热器五、润滑系的油路（一）桑坦纳2000（二）EQ6100-1 润滑系油路1、压力润滑部分•正时齿轮、曲轴主轴承、连杆轴承、凸轮轴轴承、分电器传动轴、摇臂轴、压气机。
2、飞溅润滑部分•缸壁、推杆挺杆、凸轮表面、连杆小头、凸轮轴止推板。
3、润滑油路特点•凸轮轴轴承（七道隔板）•分电器、机油泵传动轴（三道隔板、压力）•正时齿轮（前壁喷油螺塞、压力）•摇臂轴（二、四道凸轮轴轴承座处两条垂直油道）•压气机（二道隔板）（三）492Q 润滑系油路润滑油路特点•正时齿轮（前壁黄铜管）•分电器传动轴（第四道凸轮轴轴承处甩出机油、飞溅）•摇臂轴（第五道凸轮轴承座孔处垂直油道）•止推板（第一道凸轮轴轴颈处油道）润滑部位示意图。
汽车实用英语项目三 发动机冷却系和润滑系认识
Proper Names
Text learning-example
• Project 3 Acquaintance with Engine Cooling and Lubricating System
• Engine Cooling System • A 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, fan drive belt and necessary hoses (shown as Figure 3-1). • Heat transfer • 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.[1] • Cooling System Pump • Automobile engine water pumps are of many designs, but most are the centrifugal type. Sometimes the fan is installed on the water pump shaft.
Translation of difficult sentence
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采用复合式润滑系统的 上海桑塔纳轿车JV型1.8L 汽油发动机润滑油路： 发动机工作时, 机油经集 滤器 机油泵 机油滤 清器: 1) 主油道 主轴承 连杆轴承 活塞销喷溅至 活塞 曲轴箱； 2) 发动机前端第一条 斜向油道 中间轴 曲轴 箱； 3) 主油道的垂直油道 凸轮轴轴径 气缸盖回油 孔 曲轴箱。
外转子 outer rotor
进油腔 inlet
内转子 inner rotor
机油 oil
泵壳pump housing
出油腔 outlet
二、滤清器 Oil filter
为了保证滤清效果，一般使用多级滤清器：集滤器、粗滤 器和细滤器。 与主油道串联(series)的滤清器一般为粗滤器 (coarse filter)；与主油道并联(parallel)的滤清器一般为细滤器 (fine filter)，过油量约为10～30％。
§5.3
（一）齿轮式机油泵 Gear pump
齿轮式机油泵由主动轴、主动齿轮、从动轴、从动齿轮、 壳体等组成，两个齿数相同的齿轮相互啮合，装在壳体内， 齿轮与壳体的径向和端面间隙很小。主动轴与主动齿轮键连 接，从动齿轮空套在从动轴上。
Pump cover Pump body driving shaft gear
钙基(calcium-base)润滑脂、钠基(sodium-base)润滑脂、钙钠 (calcium-sodium base)基润滑。脂、复合钙基润滑脂、 通用 锂基(lithium-base)润滑脂、石墨(graphite)钙基润滑脂。
§5.2 润滑系油路
lubricating oil circuit
斜向油道
inclined oil passage
压力润滑油路 oil line
发动机工作时，机油经 集滤器：大部分机油经粗 滤器率去较大的机械杂质， 流入纵向主油道执行压力 润滑任务；小部分机油 （10%-15%），经机油细滤 器率去较细的杂质和胶质 后流回油底壳。 ①进入主油道的机油， 通过七条并联的横向油道 分别润滑主轴颈和凸轮轴 颈。经主轴颈机油从曲轴 中的斜向油道润滑连杆轴 颈。
柴 油 机 润 滑 系 示 意 图
Injection pump Oil nozzle
camshaft Main gallery pressure Regulating valve Air compressor
turbocharger
radiator
Oil filter
Relief valve
Bypass valve
main oil passage
Oil filter Gear pump
基本润滑 油路综合 演示2
Demonstration of lubrication line (oil circuit):
Micro filter
Coarse filter
二、载货车的润滑油路 Lubrication line of trucks
① oil filter
④ oil pump
②oil filter ③relieve valve
④ oil pan
报警系统 Alarm system
装有两个报警开关：低压油 压开关（旁通阀）和高压油 压开关（限压阀），均装在 既有滤清器支架上。Low pressure valve d high pressure valve 发动机在机油温度为353K, 转速为800r/min时，机油压 力大于或等于0.03Mpa； 在2000r/min时，机油压力 旁通阀 大于或等于0.20Mpa。 Bypass
泵油原理
Oil pumping principle
Driven gear shaft Driven gear Driving gear Valve spring valve
工作时，主动齿轮带动 从动齿轮反向旋转。 两齿轮旋转时，充满在齿 轮齿槽间的机油沿油泵壳壁 由进油腔带到出油腔，在进 油腔一侧由于齿轮脱开啮合 以及机油被不断带出而产生 真空，使油底壳内的机油在 大气压力作用下经集滤器进 入进油腔，而在出油腔一侧 由于齿轮进入啮合和机油被 不断带入而产生挤压作用， 机油以一定压力被泵出。
出 油 口
Driven dear
Oil outlet
Driving gear
进 油 口
Oil inlet
（二） 转子式机油泵 Rotary pump
转子式机油泵由壳体、内转子、外转子和泵盖等组成。 内转子用键或销子固定在转子轴上，由曲轴齿轮直接或间 接驱动，内转子和外转子中心的偏心距为e，内转子带动外 转子一起沿同一方向转动。内转子有4个凸齿，外转子有5 个凹齿，这样内、外转子同向不同步的旋转。
警报指示灯 Alarm indicator
油压传 感器 sensor of oil pressure
正常油压在0.1-0.4Mpa之间.
valve
限压阀 relief valve
Demonstration of lubrication line (oil circuit):
基本润滑 油路综合 演示1
Oil inlet Pump body Outer rotor Rotor shaft Inner rotor Oil outlet Oil compressed
转子齿形齿廓设计得使转子 转到任何角度时，内、外转子每 个齿的齿形廓线上总能互相成点 接触。这样内、外转子间形成4个 工作腔，随着转子的转动，这4个 工作腔的容积是不断变化的。在 进油道的一侧空腔，由于转子脱 开啮合，容积逐渐增大，产生真 空，机油被吸入，转子继续旋转， 机油被带到出油道的一侧，这时， 转子正好进入啮合，使这一空腔 容积减小，油压升高，机油从齿 间挤出并经出油道压送出去。这 样，随着转子的不断旋转，机油 就不断地被吸入和压出。
斜向油道 inclined passage
②机油从凸轮轴的第二、
第四轴颈处，经两个上油 道通向摇臂支座，润滑摇 臂轴、推杆球头和气门端 部。 ③第三横向油道通向 汽油泵传动轴；第一条横 向油道通过喷油嘴，喷射 出去的机油用来润滑正时 齿轮副。 旁通阀 ④在第一、第二横向油 Bypass valve 道之间接出的油管通到空 气压缩机曲轴中心的油道， 对其连杆润滑后的机油由 回油管回到油底壳中。
东风EQ6100-1型发动 机采用的是综合润滑方式. 曲轴主轴颈、连杆轴颈、 凸轮轴轴颈、凸轮轴止推 凸缘、正时齿轮、分电器 传动轴等均采用压力润滑 pressure lubrication ； 活塞、活塞环、活塞 销、气缸壁、气门、挺杆、 凸轮等采用飞溅润滑 splash lubrication 。
二、润滑方式 Lubricating Methods
压力润滑：Pressure lubrication
利用机油泵，将具有一定压力的润滑油源源不断地 送往摩擦表面。例如，曲轴主轴承、连杆轴承及凸轮轴轴 承、摇臂等处形成油膜以保证润.To deliver a certain pressure oil to the friction surfaces by oil pump constantly.
第九章 发动机润滑系
Chapter Nine Engine Lubrication system
概述Overview 润滑系油路 Oil circuit 润滑系主要部件Main parts 曲轴箱通风 Crankcase ventilation
§5.1
概
述Overview
一、润滑系功用 Function
密封作用Sealing： 在运动零件之间形成油膜，提高它们的密封性， 有利于防止漏气或漏油。 防锈蚀作用 Anti-rusting： 在零件表面形成油膜，对零件表面起保护作用, 防止腐蚀生锈。 液压作用 Hydraulic power： 润滑油可用作液压油，起液压作用，如液压挺 柱。To supply hydraulic pressure to lifter. 减震缓冲作用 Damping： 在运动零件表面形成油膜，吸收冲击并减小振 动，起减震缓冲作用。To absorb the shock and reduce the vibration.
综合润滑：Combination Lubricating
三、润滑系的组成 Composition
润滑系一般由油底壳，机油泵，限压阀及旁通阀，机油滤 清器，机油散热器，传感器和机油压力表、温度表等组成。
Head passage Return oil port Main oil passage
Filter outlet Oil filter Oil pan Filter inlet Oil pump
一、轿车的润滑油路 Lubricating oil galleries and lines crankshaft in cars
Return oil valve camshaft
Oil filter Relief valve Oil filter Oil pan Oil pickup and screen
润滑作用lubricating: 润滑运动零件表面，减小摩擦阻力和磨损，减小 发动机的功率消耗。To minimize the friction and wearing. 清洗作用cleaning： 机油在润滑系内不断循环，清洗摩擦表面，带走 磨屑和其它异物。To bring the impurities. 冷却作用cooling： 机油在润滑系内循环带走摩擦产生的热量，起到 冷却作用。To cool the parts.
Oil pickup and screen
四、润滑剂的种类及选用 Types and selection of lubricant 润滑剂的分类 { 润滑油 lubricating oil Classification 润滑脂grease
1、我国润滑油的分类 Grades of oil： （1）汽油机润滑油Gasoline engine oil： QC、QD、QE、QF、QG、QH （2）柴油机润滑油Diesel engine oil： CC、CD、CD-II、CF、CF-4 2、润滑脂的分类Classification: