一种新型船用柴油机油的研制

根据船用柴油机油的性能要求,通过开展基础油及各功能添加剂等对油品抗水、分水性能的影响研究,以及清净分散剂、抗氧抗磨剂等添加剂对油品高温清净性、烟炱分散性、抗磨损性及抗氧抗腐蚀性的影响研究,提出一种新型船用柴油机油配方方案。综合评定试验结果表明,研制的船用柴油机油具有优异的理化性能和良好的分散性、抗氧抗腐蚀性、抗磨性能和清净性能,并通过了FZG齿轮试验机试验和发动机台架试验。     

油酸甲酯对柴油机油热氧化性能影响研究

为研究生物柴油对柴油机油的影响,在柴油机油中分别加入质量分数10%和20%油酸甲酯,研究氧化前后油酸甲酯对柴油机油黏度、酸值和正戊烷不溶物含量的影响,量化了不同油酸甲酯含量对柴油机油各理化性能的影响百分比,从而得到不同油酸甲酯含量对柴油机油热氧化性能影响的总体百分比。结果表明:油酸甲酯的加入加快了柴油机油样品中高分子聚合物、酸性物质和正戊烷不溶物的生成,导致黏度和酸值增加;油酸甲酯对柴油机油酸值的影响最大,对黏度的影响其次,对不溶物含量的影响最小,说明加入油酸甲酯后,易较快地生成酸性物质是其诱导柴油机油氧化变质的主要原因;加入油酸甲酯越多,油酸甲酯对柴油机油热氧化性能的影响越大,这是因为随着油酸甲酯的逐渐加入,它的稀释作用会使柴油机油的性能衰减加剧。     

船舶柴油机油质量劣化规律研究

对船舶柴油机油劣化规律进行模拟氧化试验和船舶行驶试验研究,运用红外光谱和理化指标分析所取样品的酸值、碱值、闪点、氧化值等.结果表明,模拟样品和跟踪样品随着氧化时间和航程的增加,呈黏度增加、酸值升高、碱值降低,氧化值、硝化值增大的变质趋势,且理化指标和红外指标有很好的相关性.模拟氧化试验和跟踪取样的样品的红外和理化数据变化一致,因此可以用模拟试验的数据来预测实际样品的衰变.应用模拟氧化试验可以快速研究柴油机油的劣化规律,采取红外和理化相结合的方法能够评价柴油机油的质量变化程度,实现按质换油.     

水润滑硅基非氧化陶瓷摩擦学性能及其表面改性研究进展

综述了水润滑条件下硅基非氧化物陶瓷(Si3N4和SiC)摩擦学性能的研究状况,包括水润滑条件下其摩擦磨损特性以及其表面改性技术对其摩擦学性能的影响.硅基非氧化物陶瓷在水中显示出较低的摩擦因数以及良好的抗磨损能力;表面改性技术能有效地改善硅基非氧化陶瓷的水润滑摩擦磨损性能,离子注入技术是表面改性技术的一个重要发展趋势.     

氧化镧改性树脂基复合材料摩擦学性能研究

为克服树脂基制动材料易产生热衰退而失效的问题,在热压成型的树脂基制动摩擦材料加入氧化镧进行改性。通过正交试验方差分析获得摩擦学性能较优的配方,通过X-DM摩擦试验、磨损表面形貌分析等手段探讨氧化镧对材料在不同温度下的摩擦学性能的影响,并探讨其摩擦磨损机制。结果表明:摩擦材料配方组分及质量分数分别为氧化镧21. 6%、酚醛树脂12. 9%、硅酸铝纤维12. 9%、竹纤维2. 6%,其他填料50%时可获得较优的摩擦磨损性能;加入适量的氧化镧不仅能够稳定低温、高温摩擦因数,还能降低磨损率,减少热衰退的产生;在树脂基制动摩擦材料中加入适量的氧化镧后,其磨损形式由磨粒磨损为主转变为黏着磨损为主,且磨损表面出现大面积连续的摩擦膜。     

油溶性聚醚对涡轮机油的抗漆膜性能的影响

随着汽轮机和透平机械等设备的发展,涡轮机油的运行工况变得更加苛刻,油品容易发生异常氧化,并出现漆膜问题。油溶性聚醚分子具有极性,理论上对漆膜等极性氧化产物具有溶解性。为探究用油溶性聚醚改善涡轮机油漆膜问题的可行性,采用高温烘箱氧化、Dry-TOST模拟氧化、油品性能分析和橡胶相容性实验等方法,评价油溶性聚醚对涡轮机油漆膜倾向指数、油泥生成量及关键理化性能的影响,以及与密封材料间的相容性。结果表明:油溶性聚醚具有减少涡轮机油油泥生成量,降低漆膜倾向指数的作用;油溶性聚醚对涡轮机油的旋转氧弹、空气释放性、橡胶相容性具有一定不良影响,但添加一定比例油溶性聚醚的涡轮机油样品的理化性能满足技术指标要求,并可通过橡胶相容性实验。将油溶性聚醚作为涡轮机油的组分以提升其抗漆膜沉积性能的技术具有一定工业推广价值。     

基于金属催化氧化的航空液压油氧化安定性研究

为探究航空液压油氧化安定性变化规律,设计基于金属催化氧化的模拟氧化试验,研究在金属Cu与Fe的催化氧化下,15号航空液压油在不同氧化时间下的外观、黏度以及酸值变化规律,并借助GC/MS对油样组成结构进行分析。结果表明:在长时间氧化下添加金属Cu、Fe的油样颜色、黏度变化更剧烈,氧化后酸值更高,说明在金属催化氧化下,液压油的氧化安定性变差。GC/MS分析表明:在金属作用下,航空液压油长时间氧化后抗氧剂消耗更剧烈,且生成了小分子烷烃以及少量的醇、酮、酸、酯等化合物,造成了油品理化性能的变化以及氧化安定性变差。     

钛合金微弧氧化层的摩擦学性能研究

利用微弧氧化技术在Ti6Al4V合金表面制备了富含钙、磷的多孔氧化陶瓷层,研究了微弧氧化层表面形貌、组成及摩擦学性能。研究结果表明,随着电压的升高,氧化层表面微孔孔径、粗糙度和Ca、P元素含量增大,显微硬度增大。25%小牛血清润滑条件下的微弧氧化层与ZrO2陶瓷球的摩擦学实验表明,微弧氧化层的摩擦因数高于Ti6Al4V钛合金,但磨损率明显降低,表明微弧氧化Ti6Al4V合金具有良好的耐磨性能。     

某电站柴油发电机柴油机油与低硫柴油适应性试验分析

随着国家标准对柴油硫含量的严格控制,在某电厂中低硫柴油与现用柴油机油的适应性成为面临的一个重要的润滑技术问题。为了评价低硫柴油与现用润滑油的适应性,采用该电厂现用的2种柴油机油开展低硫柴油的发动机台架试验,在试验过程中监测获取柴油机的性能变化情况并通过定期的润滑油取样对柴油机油性能进行分析,评估低硫柴油对柴油机润滑和磨损的影响,以及现用柴油机油对低硫柴油的适应性。结果表明,在试验条件下燃烧低硫柴油不会对发动机性能产生不良影响,低硫柴油能与现用的柴油机油相容。     

偏苯三酸酯基础油的摩擦降解及对抗氧化性能的影响

为研究润滑油在边界润滑条件下的摩擦降解及其对润滑油性能的影响,采用四球试验机考察偏苯三酸三异辛醇酯(TMTO)、偏苯三酸三异壬醇酯(TMTD)以及偏苯三酸三异十三醇酯(TMTT)在边界润滑条件下的摩擦学性能。结果表明:分子结构对偏苯三酸酯在边界润滑条件下的润滑性能有较大影响,链长最长的TMTT的减摩与抗磨性能优于TMTO与TMTD。利用高压差示扫描量热仪(PDSC)及热重分析仪(TGA)研究四球试验前后3种基础油的抗氧化性能及热分解性,并测试摩擦试验前后润滑油的黏度与酸值变化。结果表明:边界润滑条件下的摩擦过程会导致偏苯三酸酯类基础油黏度升高、酸值降低、氧化安定性下降;润滑性能良好的基础油在一定程度上阻止或减缓润滑油本身氧化反应的发生;在边界润滑条件下,偏苯三酸酯一部分在机械剪切及水解作用下分解会生成小分子的化合物,另一部分在氧化作用下聚合生成大分子化合物。     

Building output–input function of catalytic combustion sensor to diesel vapor

The leaked diesel oil in engine room of ships volatilizes continuously. When the concentration of volatilized diesel vapor reaches the lower flammability limits, security risks will occur. In order to detect the concentration and alarm the risks, it is necessary to place sensors in engine room. This paper begins with the derivation of formula to calculate the diesel oil volume in different concentration of diesel vapor. Then it determines coefficient of the formula via analysis of the physical and chemical properties and volatilization properties of diesel oil. Experiments are designed to obtain the sensitive date to derive the function between sensor output and diesel volume. Then the fitting curve and analysis of linearity are given, and the results show that catalytic combustion sensor can meet the design requirements. In the end, it gives the application of catalytic combustion sensor using in diesel vapor detection and alarm system in engine room.     

N-酰基谷氨酸在矿物油中的摩擦学性能研究

分别在油酸和月桂酸分子中引入氮,合成了2种新型的含氮润滑油添加剂——N-油酰基谷氨酸和N-月桂酰基谷氨酸。利用四球摩擦磨损试验机考察了2种添加剂作为HVI350矿物基础油极压抗磨添加剂时的摩擦学性能,通过测定不同条件下的最大无卡咬负荷和磨斑直径及摩擦因数,分析和研究了载荷、摩擦时间、添加剂含量对矿物油最大无卡咬负荷和磨斑直径及摩擦因数的影响。试验结果表明:2种添加剂均可以明显提高基础油的承载能力和抗磨减摩性能,添加剂N-油酰基谷氨酸在矿物油中的承载能力明显优于N-月桂酰基谷氨酸,而N-月桂酰基谷氨酸对提高矿物基础油抗磨减摩性能的效果好于添加剂N-油酰基谷氨酸。试验还表明添加剂的含量并非越高越好,否则磨斑直径将增大。     

Tribological Performance of Engine Oil Blended with Various Diesel Fuels

In this study, petrodiesel (D100) and different concentrations of commercial biodiesels (B100, B50, B5) were blended with a commercial engine oil at a fixed volume ratio of 1:9 to investigate the tribological effect of the biodiesels on the antiwear performance of the engine oil. The antiwear performance of the blended oils was evaluated using a Plint TE77 reciprocating ball-on-flat tribometer at room temperature and 150°C. Results show that the antiwear performance of the engine oil blended with petrodiesel is worse than that of the other blended oils with biodiesels at both temperatures. At room temperature, the physical adsorption and local hydrodynamic effects of the blended oils dominate the tribological behavior; at 150°C, the biodiesel seems to promote the growth of a reaction film with the antiwear additives in engine oil and enhance the growth rate of chemical films. However, an excess concentration of biodiesels causes tribochemical wear, thus reducing antiwear performance.     

Temperature–friction characteristics of used lubricant from two-stroke cross-head marine diesel engines

It is now quite apparent that, in a two-stroke, cross-head marine diesel engine, the lubrication regime in the contact between piston ring and cylinder liner at the top dead centre (TDC) is of a boundary type. Therefore, the tribological performance of a system to simulate the real contact should be assessed under conditions closely resembling the operating engine environment. In the reality of engine operation, the lubricant is often contaminated by fuel and products of combustion, hence the need to study the temperature–friction characteristics of this actual lubricant under the conditions of boundary lubrication.In this paper, an oil taken from the drainage system of the engine was used. A five times heating and cooling test methodology was employed to assess tribological performance of a model contact lubricated with the actual oil. The model contact was formed by a pin sliding over a plate both made of materials used in two-stroke, cross-head marine diesel engines.Experiments showed that the general trend in temperature–friction characteristics of the used oil is similar to that of a new oil. However, the level of friction in the contact lubricated with an used oil is significantly higher than that for a new oil.     

Lubricating and physico-chemical properties of CI- 4 plus engine oil dispersed with surface modified multi-walled carbon nanotubes

This paper studies the effect of surface modification of multiwall carbon nanotubes (MWCNTs) prior to dispersion in engine oil to improve the tribological properties. The MWCNTs are stabilised in the lubricant with two different surfactants cetrimonium bromide (CTAB) and sorbitan monooleate (SPAN 80) and the effect of surfactants on the tribological properties has been studied. Pristine and surface modified MWCNTs in weight per cent range of 0·5% are dispersed in CI4 plus diesel engine oil. The foaming tendency and other physico-chemical properties of test lubricant have been studied to investigate the effect of nano materials and surfactants. The anti-wear and anti-friction properties are tested on a four ball wear tester and the comparison is made to assess the relative performance of pristine MWCNTs over surface modified MWCNTs. A strong influence of the surface modification technique is found on lubricating and physico-chemical properties. Both CTAB and SPAN 80 could keep the MWCNTs stable in the lubricant without compromising the foaming tendency of lubricant and other physico-chemical properties. The friction and wear characteristics of lubricants have improved with the dispersion of surface modified MWCNTs while there is no improvement in the properties of lubricant dispersed with pristine MWCNTs.     

离子液体对WS2纳米润滑油摩擦学性能的影响

纳米二硫化钨的润滑性能优异,但由于其在润滑油中易团聚沉降,影响了其在润滑油中抗磨减摩性能的发挥。为改善纳米WS2的抗磨减摩性能,将一种磷酸盐离子液体添加到WS2纳米润滑油中,通过四球摩擦试验机对其摩擦学性能进行测试,采用XPS、EDS和电子显微镜等表征方法对钢球磨损表面进行表征。结果表明：虽然添加离子液体后纳米润滑油的摩擦因数略微上升,但相对基础油,离子液体仍可使其摩擦因数最大降低28%,同时能显著地减小磨斑直径,最大降幅达到了44%。离子液体在摩擦过程中与WS2反应生成PW,该物质作为催化剂加速了摩擦过程中的氧化反应,生成的化合物作为化学摩擦膜减少磨损,提升润滑油抗磨减摩性能。     

绿色润滑油抗磨极压添加剂研究

矿物基润滑剂存在着生物降解性差的弊端,它所造成的污染已经引起人们的高度重视。通过四球机实验考察了猪血清在菜籽油中的抗磨和极压性能,并和传统的矿物油抗磨剂T321、T305进行对比研究。实验结果表明：和传统的矿物油添加剂相比,猪血清在菜籽油中具有很好的抗磨性能,其润滑性能是与血清中的蛋白质的组成元素有关,即碳、氢、氧、氮、硫、磷、铁等元素在钢球表面形成一层化学反应油脂膜。