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针对某船主机活塞头顶部频繁烧蚀和裂纹现象,总结出活塞头冷却腔结炭、喷油器工况不佳、主机排温过高是发生故障的主要原因,提出在以后的维护管理中的预防措施,供轮机人员参考。 相似文献
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我司3800TEU集装箱船,共有七条姐妹船主机选用了New Sluzer 9RTA84C型二冲程直流扫气高增压低速柴油机。从1994年营运至今,先后发生了活塞头烧蚀、烧穿、缸头、缸套裂纹等故障。此文通过对“SHH”轮主机No.9缸缸套裂纹故障的浅析,就主机缸套裂纹问题提出管理若干要则。 相似文献
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柴油机活塞温度场有限元计算分析 总被引:3,自引:0,他引:3
本文利用SUPERSAP有限元软件包对Sulzer 6RND68柴油机在不同工况下的活塞温度场进行计算分析,结果发现柴油机燃烧状况对活塞的温度场有着较大影响,尤其在燃烧质量不佳及柴油机超负荷运转时,活塞顶部的温度呈指数上升,这为柴油机活塞顶部裂纹和烧蚀及第一道活塞环断裂的原因提供了理论依据。并在此基础上为轮机管理人员提供了相应的管理建议。 相似文献
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某轮,日本建造,主机型号UEC60/125E,8缸,连续最大功率11200kW,额定转速158r/min。该轮往返于我国与南美洲之间,航行时间长,主机因排气阀烧蚀而停车更换排气阀是家常便饭。主机每缸各有前、中、后共三个排气阀。中阀的工作条件比前、后两阀恶劣,烧蚀更严重。刚上船,就听说航行中 相似文献
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随着船用主机增压比和压缩比的不断提高,船舶热负荷严重状况更为突出,船用主机活塞的工作条件更加恶劣,其工作的可靠性已成为影响船用主机可靠性的关键因素之一. 相似文献
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主机启动空气分配器是当主机启动时,利用分配器按照主机发火顺序,依次将控制空气传送到主机各缸的启动阀上;利用这个控制空气,将各缸启动阀打开,使主启动空气进入气缸。进入气缸的主启动空气,推动活塞运动,当活塞运转速度达到一定时,开始将燃油喷入气缸,主机进入正常运转。这时,启动空气关闭,分配器停止工作。该文进而分析了因主机无法启动而造成的故障及其原因。 相似文献
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介绍了我国港口资源的整合现状,指出港口整合可以提升港口的形象和地位,也为区域经济和城市的发展注入强大的动力。最后指出在港口资源整合中要避免的几个问题。 相似文献
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广州集装箱码头的轮胎式场桥小车制动器使用10多年后,出现了许多问题,故进行了改造.分析了轮胎式集装箱龙门起重机小车制动器的主要故障现象,提出了改造方案,并加以实施. 相似文献
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本文对现有的选定球面轴承的三种工程方法进行了分析比较.引入了“合力系数”,并给出了合力方向上投影面积的精确解. 相似文献
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分析柴油机故障中常见的机体裂纹故障原因,认为由于设计缺陷和管理及操作不当,易造成船舶柴油机缸体上的裂纹多发生在气缸套凸肩处。如不及时处理这些裂纹和故障,就会造成缸套的裂纹直至出现缸套漏水等严重后果,针对NANTAIQUEEN轮柴油机对该类型故障的检修提出具体措施。 相似文献
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The hydrophysical and hydrochemical structure of the Sea of Azov, with developed bottom anoxia, was studied during the RV “Akvanavt” cruise from July 31 to August 03, 2001. The anoxic zone with a thickness from 0.5 to 4 m above the bottom was found in all deep regions of the Sea. Concentrations of hydrochemical parameters were similar to the pronounced anoxic conditions (about 90 mmol m− 3 of hydrogen sulfide, 17 mmol m− 3 of ammonia, 6 mmol m− 3 of phosphate, 7 mmol m− 3 of total manganese). The hydrophysical structure was characterized by the uniform distribution of temperature in the upper 6–7 m mixed layer (UML). Below this a thin (0.4–0.8 m) thermocline layer was observed, just above the anoxic waters. Formation of this phenomenon was connected with that summer weather conditions. Intensive rains led to increased influx of river waters in June. That resulted in large input of allochtonous organic matter (OM) and inorganic nutrients; the latter were consumed on the additional autochthonous organic matter production. In July the weather was characterized by a significant rise in the daily averaged air temperature and large oscillations of temperature during the day. In this period a wind of constant direction was absent, but wind bursts were observed. The completed analyses showed that the formation of such a structure could be connected with the following factors: (i) positive growth trends of the daily averaged temperature and the daily oscillations of temperature, (ii) presence of wind bursts. The joint action of these factors resulted in the formation of the UML. The amplitude of wind bursts determined the depth of UML, and the value of trend determined the value of the temperature change in the thermocline. An initial presence of bottom halocline (caused by the Black Sea water influx to the bottom of the Sea of Azov) prevented the heating of the bottom layer and therefore led to an increase of vertical gradient of temperature in the thermocline. The spatial distribution of the turbulent exchange coefficient confirmed the existence of a “stagnation” area located above the anoxia zone, which is also, apparently, the reason for its occurrence. 相似文献
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