关 键 词：

粗铣汽缸盖顶底端面 说明书+CAD 柴油机 汽缸 工艺 规程 夹具 设计 底端 说明书 CAD

资源描述：

柴油机汽缸盖的工艺规程及夹具设计【粗铣汽缸盖顶底端面】【说明书+CAD】,粗铣汽缸盖顶底端面,说明书+CAD,柴油机,汽缸,工艺,规程,夹具,设计,底端,说明书,CAD

内容简介：

Of a main selection H ITACH IB & W 6S50HU diesel, the overall performance of this diesel engine is relatively good, but the design of the cylinder head sealing structure there are some flaws. Such defects caused by the use of the machine after a certain period of time, the cylinder head sealing performance significantly decreased, require frequent maintenance lifting cylinder cylinder head to eliminate leakage failure, affect the safety of ships.1 Fault OverviewThis type of diesel engine exhaust, intake manifold, fuel injectors, cylinder head gaskets and other sealing surface with no sealing process, each of these parts are required to carry out maintenance grinding.1) The main technical parameters of diesel engines. Models, H ITACH IB & W 6S50HU (4-stroke single acting turbo); cylinder diameter, 500 mm; stroke, 540 mm; maximum working pressure, 9. 10MPa; the mean effective pressure, 1. 36MPa; speed, 465 r / m in; power, 3 309 kW.2) the structure of the cylinder head seal. Between the cylinder head on cylinder contact surfaces form a planar contact seals. Jacket cooling water through the cooling water jacket leading to the cylinder head. Since there is no gasket, so each time lifting cylinder overhaul, cylinder liners must grind the shoulder and the contact surface of the cylinder head, in order to achieve no gasket sealing requirements. If the contact surface deformation or other mechanical damage, according to the specification requirements, you must use a special tool, respectively, cylinder liners and cylinder head shoulders touching the bottom of the stairs were fine grinding, grinding normally takes about 8 h.3) Analysis of reducing the sealing performance reasons.(1) due to multiple causes grinding cylinder head and cylinder liner shoulder contact surfaces to increase, reduce the sealing performance. Technical information provided by the manufacturer show that the type of diesel engine overhaul cycle of lifting cylinder 5 000 h, but according to our inspection of the turbine wheel logs, chief engineer work related records logbook, as well as some long worked in the ship access to the crew, the show since the factory ship, the host for the first time lifting cylinder overhaul when you need to contact surface is polished cylinder seal can not be achieved or 5 000 h operating time. Increase the number of grinding diesel engine overhaul, resulting in contact with the bottom of the cylinder head and cylinder liners stepped shoulder wear increases, the contact with the cylinder liners stepped shoulder to increase the contact surface of the cylinder head sealing performance is getting worse, the most severe cases The diesel engine running 300 h after the need to re-grind the sealing surface. (2) Cylinder head cooling water system is imperfect. Intermediate cooling water jacket design is thin, poor anti resilience performance, Fig. 1 A, S, P, F, respectively jacket cooling water inlet and outlet, and P is the location of the exhaust port is located in the lower portion of the cylinder head is formed local temperature, resulting in local stress increase, it is this generation of local stress so that water jacket into definite warpage. Such warpage will make cylinder liners and cylinder head contact surface unevenness, which caused uneven cylinder head or cylinder liner localized corrosion of high temperature and pressure of the gas, so often the contact surface to be milled. Position after observation of this type of machine, the first is the emergence of air leaks in 1/4 circumference P! F position on.2 improvements1) installation of the gasket.In the contact surface between the cylinder sleeve and the cylinder head gasket join by adding shims to fill the gap between the cylinder head and cylinder in order to achieve a good seal. At the same time, the use of gasket sealing structure can also improve the performance of the contact between the contact surfaces to some extent, counteract deformation due to the warpage caused by temperature differences.2) the appropriate choice of material production gasket.The maximum combustion pressure of diesel type 9. 1MPa, under the common load conditions, the combustion pressure is 8. 2MPa, under such pressure conditions, 3) increase the cooling water temperature fresh water.According diesel specification requirements, freshwater cooling water temperature should be controlled within the range of 65 to 70 degrees Celsius, the inspection engine room logs, found the machine in use, the actual cooling fresh water temperature 55 to 60 degrees Celsius, increasing the cooling fresh water temperature, reducing 1/4 stress.3 ConclusionsAfter installing the gasket after the host has continuous operation type 4 500 h, the case due to the poor sealing performance cylinder head hanging cylinder in advance did not occur, saving the cost of ship repair. Since there is no gas erosion-corrosion, good sealing surface, eliminating the grinding process, saving maintenance time.某轮主机选用H ITACH IB&W 6S50HU 柴油机,这种柴油机的总体性能比较优秀, 但是其汽缸盖密封结构的设计存在一定缺陷。这种缺陷造成机器使用到一定的时间后, 汽缸盖的密封性能明显下降,需要频繁的吊缸检修以消除汽缸盖漏气的故障, 影响船舶安全。1 故障概述该类型柴油机的排气管、进气管、喷油器、汽缸盖等密封面采用无垫片密封工艺, 每次检修均需对上述部位进行精磨。1) 柴油机的主要技术参数。机型, H ITACH IB&W 6S50HU ( 4冲程单作用涡轮增压) ; 汽缸直径, 500 mm; 行程, 540 mm;最大工作压力, 9. 10MPa; 平均有效压力, 1. 36MPa; 转速, 465 r/m in; 功率, 3 309 kW。 2) 汽缸盖的密封结构。主机汽缸套与汽缸盖之间接触面采用平面接触式密封形式。缸套冷却水经过冷却水套通往汽缸盖。由于没有垫片, 因此在每次吊缸检修的时候,必须研磨汽缸套凸肩与汽缸盖的接触面, 以达到无垫片密封要求。如果接触面变形或其它机械性损伤, 根据说明书要求, 必须使用专用工具, 分别对汽缸套凸肩和汽缸盖底部接触的台阶进行精磨, 正常情况下精磨时间约需8 h。3) 密封性能降低的原因分析。( 1) 由于多次研磨造成汽缸盖与汽缸套凸肩接触面加大, 密封性能降低。厂家提供的技术资料表明, 该类型的柴油机吊缸检修周期为5 000 h, 但根据我们查阅的该轮轮机日志、轮机长工作记录簿中的相关记录, 以及对一些在该船长期工作过的船员的访问, 表明自该船出厂后, 主机进行第一次吊缸检修的时候就需要对接触面进行研磨, 否则汽缸的密封性无法达到5 000 h的工作时间。柴油机检修时研磨次数的增加, 造成汽缸盖底部接触台阶和汽缸套凸肩磨损量增大, 汽缸盖的接触台阶与汽缸套凸肩接触面加大, 密封性能越来越差, 最严重的时候, 该柴油机运转300 h后就需要重新研磨密封面。( 2) 汽缸盖冷却水系统设计的不完善。中间冷却水套设计比较单薄 , 抗应变力性能差, 图1中的A、S、P、F分别是缸套冷却水的进出水口, 而P 的位置正好位于汽缸盖排气口的下部, 形成局部的温差, 造成局部应力加大, 正是这种局部应力的产生使得水套发生一定的翘曲现象。这种翘曲 现象也会使得汽缸套