缸盖加工基本工艺概述.doc

中文译文 发动机缸盖加工工艺概述一、发动机缸盖功用 气缸盖是发动机重要零件之一，位于发动机上部，其底平面经汽缸衬垫，用螺栓紧固在气缸体上。重要功用如下：1、封闭气缸上部，并与活塞顶部和汽缸壁一起形成燃烧室。2、作为定置气门发动机配气机构、进排气管和出水管装配基体。3、气缸盖内部有冷却水套，其底面上冷却水孔与气缸体冷却水孔相通，以便运用循环水带走发动机高温。二、气缸盖构造特点气缸盖应具备足够强度和刚度，以保证在气体压力和热应力作用下，可以可靠工作。气缸盖形状普通为六面体，系多孔薄壁件，其中咱们当前481缸盖上，加工数量多达100个。锻造最薄处只有4.5毫米。 三、缸盖材料与毛坯制造1、缸盖材料： 缸盖材料，当前发动机厂家普通选用铝合金。由于铝合金导热性能较好，有助于恰当提高压压缩比，质量也较轻，可以减少整车、整机重量。但是铝合金缸盖刚度差，使用过程中容易变形。 缸盖附件上，此前气门座材料普通采用耐热合金铸铁，气门导管普通采用铸铁。当前粉末冶金在气门阀座和导管上运用越来越多了，并且诸多复杂形状也能锻导致型，不需要再加工了。但耐磨性不如铸铁。 裂纹：锻造应力导致； 冷隔：浇注过程中铝水冷却速度不一致导致； 表面疏松：浇注温度不当或铝水成分不当； 气孔：浇注铝水中夹杂了空气； 砂眼：浇注铝水中夹杂了杂质； 沾砂：工件出炉温度不当或没有喷丸等。四、缸盖加工难点：1、平面加工工艺 缸盖顶面、底面和进、排气面都是大面积平面，精度规定高（平面度0.04，垂直度0.05，位置度0.10），并且有也许是所有工艺过程基本，例如480缸盖就是。 这就对机床几何精度和刀具调节精度规定比较高。 此前缸盖大平面加工，采用硬质合金刀片加工，并配一种金刚石修光刃。当前，如果毛坯状况好话，所有采用金刚石刀片进行加工，可以较好提高加工后表面粗糙度。2、高精度孔加工 气缸盖上气门阀座、导管孔、挺杆孔和凸轮轴孔等孔系，有配合关系。其尺寸精度、位置精度和表面粗糙度规定极为严格。因此这些高精度孔系加工工序是缸盖工艺中核心工序，应予以充分注重。 1）、缸盖气门阀座、气门导管精加工 缸盖气门阀座、气门导管同步与发动机气门配合，因此同轴度规定比较高；此外气门阀座与气门锥面进行密封配合，对于圆度规定也非常高。 对于上述部位加工过程，当前480缸盖分解如下： 机床主轴快进-工进-主轴重新启动，加工气门阀座锥面-主轴停止、并后退一端距离-主轴重新启动，枪铰加工气门导管（干通） -加工完毕-工进退刀-主轴回推。 这样做好处，就是一次定位，加工完毕气门导管和气门阀座，可以减少重复定位误差，提高气门导管和气门阀座同轴度。 此外，主轴在重新启动后，加工气门阀座时候，进刀方向如果沿着阀座径向方向，此种加工方式成为“车”阀座，可以提供加工精度。如果进刀方向沿着阀座轴向方向，称为“锪”或 “镗”阀座。 由于气门阀座和气门导管材料变化，加工过程中选用刀具也在不断发生变化。此前硬质合金刀片逐渐被CBN刀片所代替，很大提供了加工效率和加工质量。并且，如果有铜基粉末冶金材料气门阀座和气门导管，还可以采用PCD刀片进行加工。 2）、缸盖挺杆孔、气门导管底孔加工 这些孔加工，虽然加工精度比较高，但是，只要选好加工余量、参数和刀具，加工过程基本没有什么问题。 3）、缸盖凸轮轴孔加工 缸盖凸轮轴孔，就是缸盖最长孔，如果分段加工话，虽然可以保证凸轮轴孔加工精度，但是无法满足凸轮轴孔同轴度规定，因此规定精加工一次加工成型。对于长度为500mm左右刀杆而言，如何消除刀杆自身重力所产生影响？ 对于专机自动线而言，普通都带有镗模架以消除影响，对于比较大发动机，有也许带有好几种镗模架。 对于加工中心，当前基本已经取消镗模架，运用刀具自导向来消除刀杆重力影响。刀杆构造特点是：在刀杆圆周上，均匀布置一种刀刃和三个导向条。刀杆数量普通是一长一短。 加工过程如下： 先由短刀杆加工一种凸轮轴孔（至半精加工尺寸）-退刀-长刀杆完毕所有凸轮轴孔半精、精加工。 4）、缸盖加工过程毛刺 对于铝合金缸盖，由于是塑性材料，加工过程中不可避免产生毛刺。 对于加工过程中毛刺，除了要合理选用加工参数、刀具参数外，还可以提高工件材料硬度，也可以弱化加工过程中毛刺产生。 当前加工过程中，重要有如下几种方式去除加工毛刺： 一、尼龙毛刷去毛刺，多用于大加工表面和大孔系去毛刺； 二、高压水去毛刺，多用于深油孔去毛刺，也有运用旋转水柱去大面或大孔毛刺；三、表面喷丸或表面抛丸：多用于铸件表面毛刺、飞边解决，影响工件清洁度；四、电火花去毛刺：用于比较难去除毛刺，例如合金钢毛刺，对于不规则毛刺，去除比较困难；五、氢氧爆破去毛刺：运用氢氧燃烧产生压力和高温气流，将附于工件表面产生毛刺消除，但是对于工件毛坯规定比较高，补焊、裂纹、冷隔均有也许导致工件报废。 5）、缸盖清洗 缸盖清洗工序是缸盖重要辅助工序之一。由于发动机对缸盖清洁度规定非常严格（咱们当前AVL缸盖清洁度指标为：7mg），而缸盖又是一种多孔型腔构成复杂锻造箱体，如清洗不彻底而使砂子和铝屑等进入发动机润滑系统或汽缸中，则会直接影响发动机工作和使用寿命。因此，应当充分注重缸盖清洗工序。 对于缸盖清洗机而言，当前普通都带有射流清洗工位，相称于预清洗工位，工件在水箱中翻转，清洗喷嘴带有压缩空气水流，从而达到工件粗步清洗效果。 对于有装配需求或不易清洗干净之处，清洗机上普通配备有顶点定位清洗工位，就可以将规定部位清洗干净了。但会导致机床长度增长、喷嘴布置不以便等，并且还无法满足柔性清洗需求。 对于缸盖水道清洗，由于受到毛坯锻造质量影响比较大，因此也是一种清洗难点。五、典型缸盖加工工艺流程 下面咱们以AVL缸盖加工工艺流程为例，理解在加工中心上是如何加工缸盖零件： OP10：毛坯上料； OP20：毛坯基准定位，加工缸盖进、排气面（除了进气侧面油孔不加工外）； OP30：排气侧面精基准定位，加工缸盖顶面、前、后端面加工内容； OP40：排气侧面精基准定位，加工缸盖顶面、燃烧室面加工内容；OP60：清洗工序；OP70：缸盖水道和油道试漏；OP80：缸盖气门阀座、气门导管装配（常温装配）；OP90：缸盖凸轮轴盖、定位销装配，凸轮轴盖螺栓自动拧紧；OP100：排气侧面精基准定位，完毕缸盖顶面和燃烧室面精加工（气门导管和气门阀座精加工）；OP110：排气侧面精基准定位，完毕缸盖凸轮轴孔和前、后端面精加工；OP120：终清洗工序；OP130：涂胶、压装碗形塞、钢球；OP140：试漏机；OP150：目视检测；OP160：打号工序；OP170：成品下料。 从上面工艺流程来看，已经运用了加工中心制造技术、敏捷制造技术等较为当前生产线制造技术。 此外，为了更好进行多品种共线生产，缸盖设计、工艺基准都在向排气侧转化，以便更好进行共线生产。六、缸盖加工注意事项：1、缸盖尺寸较大时，由于内应力重新分布而产生变形，会严重影响缸盖加工精度。普通原则就是先面后孔，粗加工和精加工尽量分散，以保证加工应力释放。2、为了避免缸盖结合面划伤，普通将结合面精加工尽量放在后续工序。3、振动清理内腔铁屑杂物工序，应安排在与水腔关于加工工序后来最为适当。免得震动清理后，又加工与水腔关于部位，又有铁屑掉进去，后来还需要进行清洗。4、加工过程中，特别是自动化大批量加工过程中，最佳带有夹具喷气检测和刀具折断检测，以减少加工过程中，不必要损失。七、结束语 以上就是发动机缸盖加工工艺概述，真正知识来自于现场，来自于时间。英文原文Overview of engine cylinder head machining process First，the function of the engine cylinder headCylinder head of the engine of the main parts，the upper part of the engine，the cylinder liner via the bottom plane，with bolts on the cylinder body. The main function is as follows: 1，the closed upper cylinder and the piston and the cylinder wall at the top with a combustion chamber. 2，as a set-valve engine valve train，intake and exhaust pipe and the outlet pipe assembly base. 3，inside the cylinder head cooling water jacket，the bottom surface of the cooling water hole of the cylinder block cooling water hole communicating in order to use the engine temperature circulating water away. Second，the structural characteristics of the cylinder head the cylinder head should have sufficient strength and rigidity to ensure that the gas pressure and under the action of thermal stress，work reliably. cylinder head shape is generally hexahedral，based porous thin pieces，of which we are now 481 cylinder head，processing up to 100 the number of holes. Casting is only 4.5 mm at the thinnest. Third，the head material and blank manufacturing 1，cylinder head material: Cylinder head material，and now the engine manufacturers generally use aluminum. Because aluminum thermal conductivity is better，is conducive to an appropriate increase in pressure compression ratio，the quality is also lighter，you can reduce the vehicle，the whole weight. But the difference in stiffness aluminum alloy cylinder head，easily deformed during use. cylinder head attachment，previously valve seat material commonly used heat-resistant alloy cast iron，cast iron valve guides commonly used. Powder metallurgy is now the seat of the valve and conduit on the use of more and more，and many complex shapes can also be casting，without reprocessing it. However，abrasion resistance than cast iron. Crack：casting stress caused; Cold compartment：aluminum casting process water cooling rate caused inconsistent; loose surface：aluminum water pouring temperature irregularity or improper ingredients; stomatal：casting aluminum water mixed with air; trachoma：cast aluminum water mixed with impurities; dip sand：improper or no workpiece temperature baked shot and so on. Four，cylinder head machining difficulties: 1，plane processing the cylinder head top surface，a bottom surface and into the exhaust area planar faces are large，high precision (flatness 0.04 0.05 verticality，the position degree of 0.10)，and may be the basis for all of the process，for example，the cylinder 480 Cover is. This geometric accuracy of the machine and tool adjustment is relatively high precision. Previous large flat cylinder head machining，machining with carbide blade，and with a diamond blade Danxiu Guang. Now，if the situation is good rough，all using diamond blade for processing，may well improve the surface roughness after processing. 2，high-precision machining holes cylinder head valve seat tube hole，holes，etc. tappet camshaft bore holes and the Department has with the relationship. Its dimensional accuracy，position accuracy and surface roughness requirements are extremely stringent. So these high-precision machining holes of cylinder head technology process is the core process，should be given full attention. 1，cylinder head valve seats，valve guides finishing cylinder head valve seats，valve guides with both the engine valve，so that the coaxial degree is relatively high；additional valve seat for sealing engagement with the valve cone，the roundness requirements are very high. For the processing of these parts，now 480 head breaks down as follows: Fast Forward - spindle work into - spindle restart processing valve seat cone - spindle stop and back end of the spindle distance - restart gun reaming valve guides ( QianTong) - finished processing - workers and retract - spindle pushed back. The benefit is that once positioned，processing is complete valve guides and valve seat，positioning error can reduce duplication and improve the valve guides and valve seat concentricity. In addition，the spindle after the restart，machining the valve seat when the feed direction if the radial direction along the seat，processing methods such as car seat，providing precision. If the feed direction along the axial direction of the valve seat，called countersink orBoring seat. Because the valve seat and valve guide material change in the selection process of the tool is constantly changing. Carbide inserts before gradually replaced CBN inserts，great processing efficiency and provide quality. And if there is copper powder material valve seat and valve guide，PCD inserts can also be used for processing. 2，cylinder head tappet hole bottom outlet valve guide machiningThese hole machining，although precision is relatively high，however，as long as the selected allowance，and the tool，the process basically no problem. 3，cylinder head camshaft hole machiningCamshaft cylinder head bore，the cylinder head is the longest holes in the staging process，even though the camshaft hole processing can ensure accuracy，but can not meet the requirements of the camshaft hole concentricity，it requires a finish molding. For the length of the shank is about 500mm，the arbor itself how to eliminate the impact of gravity?For the purposes of automatic line plane，generally with boring mold to eliminate the influence of the relatively large engine，there may be several boring with mold. For machining centers，now has basically been canceled boring mold，the use of self-oriented tool to eliminate the effects of gravity Arbor. Arbor structure is characterized by：the circumference of the holder，evenly arranged a blade and three guide bars. Arbor quantity is generally a long，one short.Process as follows:First by knife rod processing a camshaft hole (to the semi-finished dimension) - retraction - Long shank complete all the camshaft hole semi-intensive，finishing. 4，cylinder head machining process burr For aluminum alloy cylinder head，because it is a plastic material，processing inevitable glitches.For processing glitches，in addition to a reasonable selection of machining parameters，tool parameters，but also can improve the hardness of the workpiece material，it can weaken the processing of burrs.Now the process，mainly in the following several ways to remove burr:A nylon brush deburring，and more for the processing of large surfaces and large holes of deburring;Second，the high-pressure water deburring，used for deep-hole deburring，there are also a rotating water jet Omo or large burr hole; Third，the surface shot peening or surface：the surface used for casting burrs processing，affecting the cleanliness of the workpiece; Fourth，the spark deburring：for the more difficult to remove burrs，such as steel burrs，for irregular burr removal more difficult; five hydroxide blasting deburring：the use of hydrogen combustion pressure and high-temperature air，will be attached to the surface of the workpiece burrs eliminated，but high demand for workpiece blank，patching，crack，cold traps are likely to lead to the workpiece scrapped. 5，cylinder head cleaning Cylinder head cleaning process is one of the main auxiliary processes. Cleanliness on the head because the engine was very strict (We now head AVL cleanliness indicators： 7mg)，while the cylinder head is a complex consisting of a porous cavity casting box，if not thoroughly cleaned leaving the sand and aluminum shavings from entering the engine lubrication system or cylinder，it will directly affect the work and life of the engine. Therefore，we should pay full attention to the cylinder head cleaning process.For head cleaning machine，it is now generally with jet cleaning station，the equivalent of pre-cleaning station，flip the workpiece in the tank cleaning nozzles with compressed air flow from step to achieve the effect of cleaning the workpiece thick. For assembly requirements or difficult to clean the place，generally equipped with a washing machine cleaning station vertex positioning，you can clean the parts required. But will cause the machine to increase the length inconvenience nozzle arrangement，but can not meet the needs of flexible cleaning. For head cleaning waterways as being rough casting quality is relatively large，it is also a cleaning difficult. Fifth，the typical process flow cylinder headHere we AVL cylinder head machining process，for example，to understand how the machining center machining cylinder head parts:OP10：blank feeding;OP20：rough benchmark positioning，processing cylinder head intake and exhaust side (in addition to the intake side of the hole is not working outside);OP30：benchmarking exhaust side finishing，processing the top surface of cylinder head，before and after the machining face;OP40：benchmarking exhaust side finishing，processing cylinder head top surface，the combustion chamber surface machining content; OP60：the cleaning process; OP70：head waterways，and oil leak; OP80：cylinder head valve seat and valve guide assembly (assembly room temperature); OP90：camshaft cylinder head cover，pin assembly，automatic camshaft cap bolts tightened; OP100：exhaust side finishing benchmarking，complete cylinder head top surface and the combustion chamber surface finishing (valve guides and valve seat finishing); OP110：exhaust side finishing benchmarking，complete cylinder head camshaft hole and the front and rear end finishing; OP120：Final cleaning process; OP130：gluing，pressing bowl plug，ball; OP140：leak testing machine; OP150：visual inspection; OP160：marking process; OP170：finished cutting. From the above process point of view，have been used for the machining center manufacturing technology，manufacturing technology and other more agile production line manufacturing technology now.In addition，in order to better carry out multi-species collinear production，cylinder head design，technology benchmarks are converted to the exhaust side，in order to better carry out collinear production. six，cylinder head machining note:1，cylinder head size is large，due to internal stress redistribution and deformation，will seriously affect the cylinder head machining accuracy. The general principle is that after the first surface hole，roughing and finishing try to spread in order to ensure processing stress release.2，in order to avoid surface scratches head combination will generally try to put up with surface finishing processes.3，the vibration cavity iron debris clean-up process should be arranged in the cavity with water related processes after the most appropriate. Lest shock after cleaning，and processing and related parts of the water chamber，there are iron filings fall into the future also need to be cleaned.4，the process，especially during the automatic processing of large quantities，preferably with air-jet test fixture and tool breakage detection to reduce the processing，unnecessary losses. VII ConclusionAbove is an overview of engine cylinder head machining process，the real knowledge comes from the scene，from the time.