Phosphorus volatility of engine oils: Use of the phosphorus emission index

The concept and principles of the phosphorus emission index (PEI) were introduced during 2002. This paper reviews the background of the benefits and concerns regarding phosphorus additives. In particular, the paper focuses on the two factors until recently assumed important in phosphorus volatility and catalyst contamination: oil volatility and initial phosphorus concentration. Studies of Selby—Noack data on 1300 oils collected in 1999 and 2000 by the Institute of Materials showed the invalidity of the two assumptions and this led to the concept of the PEl. Further studies in conjunction with a field taxi study by the Ford Motor Company to determine the correlation of the PEl with catalyst contamination not only showed correlation, but also proved that phosphorus volatility was independent of either oil volatility or fresh oil phosphorus levels. Rather, phosphorus volatility was, as earlier predicted, found to be highly dependent on its chemistry and the chemistry of other additives. Engine oil formulation using the PEl technique should markedly reduce phosphorus volatility and resultant catalyst contamination.     

Sulphur emissions from engine oil: Information from the sulphur emission index

Data published by the Institute of Materials including information on the volatility, sulphur content, and sulphur volatility of 913 engine oils were compiled. These engine oils were collected in three geographic regions: North America, Europe, and Asia. The volatility data were generated using a Selby—Noack instrument in which all volatilised material is collected for the further analysis of phosphorus and sulphur content. It was found that under the normal Noack test exposure conditions of 250°C for one hour, the sulphur emission index (a measure of sulphur volatility in mg/l) varied markedly among the engine oils. In a correlation study, a minor correlation of up to %R²= 15 was found between sulphur volatility and oil volatility while a greater correlation of up to %R² = 39 was found between sulphur volatility and sulphur content of the formulated engine oils. A new concept and application of the sulphur volatility ratio may be useful in explaining the observations concerning sulphur volatility dependence.     

Development and Significance of the Phosphorus Emission Index of Engine Oils

This paper reports the author's effort to verify some of the present assumptions regarding causes and relationships in the volatility of engine oil phosphorus. Using Selby‐Noack volatility data from 1300 engine oils collected by the Institute of Materials in three areas of the world, volatilised phosphorus showed very low statistical dependence on either oil volatility or phosphorus concentration in the fresh oil. Rather, the data seemed to indicate that the chemistries of the phosphorus‐containing additives and their formulation with other additives were the controlling cause of phosphorus volatility and, by extension, emission level. The study permitted the development of a phosphorus emission index that predicts the emission potential of a formulated oil based on the amount of phosphorus found in the volatilised oil collected in the Selby‐Noack test.     

A new approach to the Noack volatility test

This paper reports on the method and preliminary results of a significant modification of the Noack volatility test. This modification permits collection and examination of the volatile products as well as of the residue. The analysis of such volatiles by chromatography and spectroscopy revealed surprising information that is especially relevant in the face of increasingly difficult automotive and heavy duty engine emission limitations. The data also showed very close agreement with the Unified Test Method for the Noack Volatility Test now covered by CEC L-40-T-87. Important to operators, the authors' modified Noack apparatus avoids the use of the toxic Wood's Metal of the earlier Noack apparatus.     

Engine oil contribution to diesel exhaust emissions

The reduction of harmful pollutant emissions as well as CO₂ emissions emanating from motor vehicles will be of considerable interest in the coming decades. Emissions legislation will be the guiding principle in the development of new technologies and vehicles. More attention will have to be paid to off‐road vehicles, especially tractors, if the production of healthy food and the maintenance of a cleaner environment are not to be compromised. Therefore, one the biggest challenges facing the automotive industry is to improve fuel economy, both to conserve natural resources and to limit pollutants and CO₂ emissions. Better fuel efficiency and consequently lower emissions will require new materials, new lubricants and low‐emission fuel. Engine lubricants help to improve vehicle efficiency but contribute engine exhaust emissions. This paper deals with the influence of engine lubricants on diesel exhaust emissions. Investigations have shown a clear effect of lubricant oil on emissions, which depends on lube oil characteristics, especially sulfur content, metal content, volatility and density. Copyright © 2006 John Wiley & Sons, Ltd.     

The influence of engine oil on diesel exhaust emissions

Increasingly stringent emission legislation, together with the requirements for improved diesel engine performance, such as fuel economy, friction reduction, and extended drain intervals, have led to attention being focused on engine oil quality. The use of low‐friction engine oils can improve engine fuel efficiency and lead to a significant reduction of gaseous emissions. Therefore, engine oil is of importance when considering engine design parameters. This paper describes a study of the contribution of engine oil to diesel exhaust emissions. The investigations have shown that diesel engine particulate emissions as well as hydrocarbons and NO_X emissions depend on the lubricant oil properties, in particular on the sulphur content, volatility, and metal content.     

Assessment of the useful life of current long‐drain and future low‐phosphorus engine oils

The assessment of engine oil useful life is an important step in the development of future low‐phosphorus, catalyst‐compatible, and long‐drain engine oils. This paper describes the development and application of a new laboratory screening test, the Ford oil ageing test (FOAT), for the assessment of engine oil useful life. FOAT simulates the Sequence IIIE engine dynamometer test and evaluates oils on the basis of viscosity increase. It correlates well with both single‐ and double‐length Sequence IIIE test results. FOAT allows for inexpensive screening of candidate oils prior to engine tests and is currently being used in the evaluation of future low‐phosphorus engine oils. This comparative study has demonstrated that low‐phosphorus, catalyst‐compatible engine oils can be formulated to provide a similar useful life to current commercial long‐drain oils.     

电控汽油喷射发动机燃油压力的测量方法

介绍了对电控发动机进行性能检测与故障诊断的基础项目之一的燃油压力检测的具体方法,并通过分析检测结果对燃油系中的一些元件做出性能判断.     

Analysis of oil consumption in cylinder of diesel engine for optimization of piston rings

The performance and particulate emission of a diesel engine are affected by the consumption of lubricating oil.Most studies on oil consumption mechanism of the cylinder have been done by using the experimental method,however they are very costly.Therefore,it is very necessary to study oil consumption mechanism of the cylinder and obtain the accurate results by the calculation method.Firstly,four main modes of lubricating oil consumption in cylinder are analyzed and then the oil consumption rate under common working conditions are calculated for the four modes based on an engine.Then,the factors that affect the lubricating oil consumption such as working conditions,the second ring closed gap,the elastic force of the piston rings are also investigated for the four modes.The calculation results show that most of the lubricating oil is consumed by evaporation on the liner surface.Besides,there are three other findings:(1) The oil evaporation from the liner is determined by the working condition of an engine;(2) The increase of the ring closed gap reduces the oil blow through the top ring end gap but increases blow-by;(3) With the increase of the elastic force of the ring,both the left oil film thickness and the oil throw-off at the top ring decrease.The oil scraping of the piston top edge is consequently reduced while the friction loss between the rings and the liner increases.A neural network prediction model of the lubricating oil consumption in cylinder is established based on the BP neural network theory,and then the model is trained and validated.The main piston rings parameters which affect the oil consumption are optimized by using the BP neural network prediction model and the prediction accuracy of this BP neural network is within 8%,which is acceptable for normal engineering applications.The oil consumption is also measured experimentally.The relative errors of the calculated and experimental values are less than 10%,verifying the validity of the simulation results.Applying the established simulation model and the validated BP network model is able to generate numerical results with sufficient accuracy,which significantly reduces experimental work and provides guidance for the optimal design of the piston rings diesel engines.     

Effect of palm oil methyl ester and its emulsions on lubricant degradation and engine component wear

This paper presents the results of experimental work carried out to evaluate the effect of palm oil methyl ester also known as palm oil diesel (POD) and its emulsions, as alternative fuels, on unmodified indirect‐injection diesel engine wear and lubricant oil deterioration compared with ordinary diesel (OD). A constant 2500 rpm engine setting at half throttle was maintained throughout the wear debris and lubricant oil analysis period for 20 h for each fuel system. Samples of lubricant oil were collected through a one‐way valve connected to the crankcase sump at intervals of 4 h. The first sample was collected immediately after the engine had warmed up. The same lubricating oil, a conventional SAE 30, was used for all experiments. A multi‐element oil analyser was used to measure metal wear debris and lubricating oil additive depletion for the used lubricating oil. An ISL automatic houillon viscometer (ASTM D 445) and potentiometric titration (ASTM D 2896) were used to measure the viscosity and total base number, respectively. The lubricant oil analysis results for POD, OD, and their emulsions containing 10% water by volume were compared. Very promising results were obtained. The accumulation of metal wear debris in crankcase oil samples was lower with POD and its emulsion compared with the OD fuel. The addition of 10% water (by volume) to POD showed a promising tendency for wear resistance.     

Statistical study of organomolybdenum compounds in an engine oil formulation and the results of engine testing

Organomolybdenum compounds are versatile lubricant additives of interest in the design of engine oils to meet the new ILSAC (International Lubricant Standardization and Approval Committee) GF‐3 performance standard, especially for fuel efficiency. In this work, organomolybdenum and 13 other components were studied by experimental design and statistical analysis to determine their effects on friction, wear, and oxidation properties. The resulting linear model was used to construct a trial engine oil formulation. Engine test results, including some new tests required for ILSAC GF‐3, confirmed some of the strengths of organomolybdenum compounds, as well as their sensitivity to other additives in the formulation.     

A new engine oil optimised for ecologically sensitive operational areas

In recent years, environmental awareness and legislation have focused public attention on vehicle emissions. Consequently, more research has been devoted to emissions and pollution by lubricants. A number of studies has been carried out to understand lubricant-related emissions and leak rates as well as the effects on fuel economy of using low viscosity grades of lubricant. The purpose of the present investigation was to develop for use in gasoline and diesel engines a crankcase lubricant which contained improved performance in engine cleanliness with fuel economy and a low rate of particle emissions. Emphasis was placed on low toxicology and rapid biodegradability because of the risk of unintentional emissions. Such a sophisticated lubricant is desirable not only for normal road vehicles but also and especially for use in ecologically sensitive areas. During the development of this lubricant, numerous laboratory tests were performed. In order to assess the quality and the fuel economy of the new lubricant, tests were carried out on an engine test rig and on a vehicle test bench. Field tests were run with various vehicles and stationary engines, using different fuel types. Unleaded gasoline, diesel fuels with a varying sulphur content, and rape seed oil methyl ester (RME) were used. This paper summarises the results of this investigation.     

BWH1.6L宝来轿车发动机检修分析

新宝来轿车在行驶40 000多km后,出现机油压力不足、报警灯闪亮的故障。在进行认真分析和大量排查的基础上,最终确定该车的故障是由机油集滤器堵塞造成的。经对集滤器及其相关连接件进行彻底的清洗与更换后,排除了故障,恢复了汽车的正常行驶。本文还列举了造成机油压力不足的一系列可能的相关原因,供汽车驾驶员与维修人员参考。     

Effects of refined palm oil (RPO) fuel on wear of diesel engine components

In this particular research work, the effects of refined palm oil (RPO), as alternative fuel, on wear of diesel engine components are assessed. Fleet testing is carried for the qualifying candidates diesel fuel replacement, i.e. 100% RPO fuel or 50% RPO and 50% conventional diesel fuel mixture. The base line of the fleet testing is using pure conventional petroleum diesel fuel as an energy source in one of the tested vehicles in the fleet. Analysis of used engine lubrication oil, taken when the oil was changed on the vehicles, was compared to the analysis of used oil samples pulled from 100% diesel fuel engines. The finding suggested that the pure RPO and RPO blended fueled engines were wearing at a normal rate.     

Synthetic two-stroke engine oil as a tool of exhaust emission control

Polypropylene oligomers were used to formulate two-stroke (2T) engine oil for once-through lubrication systems, to enhance the exhaust emission characteristics of two-stroke engines. The oligomers alone are suitable from a stability viewpoint, but must be reinforced with polyol-ester components to have good load-carrying capability. Both ash-forming and ash-free commercial additive packages can be used to formulate the end-product. The exhaust stream includes the unburnt portion of the fuel:oil mixture. The lubricating oils formulated on polypropylene oligomer base do not contain polynuclear aromatics, the sulphur-dioxide emission is due to the sulphur content of the fuel and additive (if any). On a bench test, the hydrocarbon emission was significantly lower using polypropylene oil, in comparison to using a commercial mineral-oil-based composition.     

Evaluation of metallic elements in oil for an engine fault‐diagnosis system

One of the main problems in using oil analysis for predictive maintenance is the processing of the results. The oil analysis technique allows one to obtain relevant information about the state of the lubricant, the engine, and other auxiliary elements. However, it is necessary to process this information and to define the references with which the numerical results must be compared. The evaluation of metallic elements, wear particles, or contamination particles is more difficult, because factors such as engine metallurgy, engine use, and age must be considered. Therefore, the effect of various factors on the value measured, such as refills, different periods of sample taking, or types of oils, must be eliminated. A system to evaluate metallic elements in oil for an engine fault‐diagnosis system is presented in this paper.     

Measurement of oil film thickness in big-end bearings and its relevance to engine oil viscosity classifications

Minimum oil film thickness MOFT measurements have been carried out in big-end bearings of V6 and in-line four-cylinder gasoline engines during engine operation. MOFT decreases with increasing crankshaft speed above 2000 r/min. The most severe practical steady-state operation is high-speed cruising. Maximum shear rates are in the region of 10⁷s⁻¹ at 4000 r/min. the dynamic viscosities at a shear rate of 10⁶s⁻¹ correlate significantly better with monograde MOFT data than with multigrade data; the correlation parameters for mono- and multigrade data are also significantly different. Although the dynamic viscosity measurement correlates with multigrade data better than the low-shear rate kinematic viscosity, the differences are not always significant at the 95% confidence level. Some other rheological parameter or combination of parameters may be better than either kinematic or dynamic viscosities.     

The influence of lubricating oil on deposits formation in a diesel engine under the operation condition of high power density

The requirements of higher power density and stricter regulations on emissions of internal combustion engines lead to lubricating oil's role shifting from simply lubricating to adapting higher power density and to achieving lower emissions. An important factor influencing an engine's power and emissions is the deposits in the engine. Lubricating oil is a chief contributor to deposits formation. The objective of this paper is to investigate the influence of lubricating oil on deposits formation when the engine is operated under high power density. Metal elements content in lubricating oil and changes to power and emissions were measured to verify deposits changes. Different power densities can be achieved by adjusting the fuel supply system in the engine. Three kinds of synthesised lubricating oils were used in the investigation. The temperature of the oil pan and cooling water was strictly controlled. The experimental results demonstrated well the influence of the quality of different kinds of oil on deposits formation. Copyright © 2013 John Wiley & Sons, Ltd.     

The effects of a demulsifier on the interface of marine engine oil and water

The water‐shedding property and the interfacial tension of marine engine oils with various additives have been assessed and analysed in this paper. It is concluded that the weak water‐shedding property was mainly due to the molecular structure and the interfacial property of sulphonate detergent, which can adsorb on the oil–water interface intensely to form a strong interfacial film and prevent coalescence of droplets. The impact of a demulsifier to the water‐shedding property and the interfacial tension indicated that demulsifier improved the water‐shedding property of marine engine oil in the manner of being much easy to adsorb onto the interface but formatting a flimsy interfacial film. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of lubricating oil additives on particle size distribution and total number concentration in diesel engine

This paper investigates the characteristics of particle size distribution in exhaust gas of engine fuelled with pure diesel and with diesel mixed with base oil or with oil additives. The experiments are conducted on a turbocharged diesel engine with fast particulate spectrometer DMS 500 connected to the exhaust pipe. Base oil and two kinds of commonly used lubricating oil additives, antioxidant additives and antifoaming additives, are chosen to be added into the fuel, with the concentrations being 0.5%, 1.0% and 1.5% of fuel weight individually. The particle size distribution is measured under medium load (100 Nm) and full load at different speeds. The results indicate that the existence of base oil or oil additives shows great influence on particle size distribution. Copyright © 2012 John Wiley & Sons, Ltd.