SAE 15W-40 Research Articles

Friction coefficient and performance evaluation of plain journal bearing using SAE 5W-30 engine oil

Friction is a crucial parameter in tribological applications such as power transmission, crankshafts, gears, cams, bearings, and other rotating machine parts or components. Due to the relative motion of the shaft and bearing, friction needs to be analyzed according to all lubrication states of the journal bearing. The friction coefficient was significantly reduced using piezo-viscous SAE 5W-30 engine oil in this study. An adequate lubricant pressure is obtained using this approach to produce a suitable oil film thickness. Minimal variation in lubricant temperature was obtained which prescribes the sustainability of the lubricant. The bearing performance was observed through computational fluid dynamics analysis under different viscosities. The SAE 5W-30 lubricant-containing 0.052693 Pa s viscosity minimized bearing deformation and stress formation at 500, 750, and 1000 r/min. A new bearing material as gun-metal having good bearing properties and good resistance to corrosion has been proposed in this study.

Analysing the frictional properties of micro dimpled surface created by milling machine under lubricated condition

The work investigated the friction reduction capability of micro-dimples created on a steel plate (disc) using a vertical milling machine under lubrication condition. A L25 orthogonal array was used to determine the combinations of various parameters. Wear tests were carried out using a pin on disc tribometer. SAE 10W30 was used as lubricant which was supplied intermittently between the interface of pin and disc. After the tribo test the optimized dimple parameters exhibited a decrease of 49.76% coefficient friction over the non-dimpled disc. The surfaces were further analysed using a three dimensional profilometer and scanning electron microscope. Artificial neural networks were employed to understand the influence played by each parameter on the coefficient of friction during the tribo test.

Lubricated tribology of hybrid AMMC–steel sliding contact: A comparative investigation between fully formulated commercial engine oils and surfactant functionalized MWCNT–base oil formulation

The aim of the present study is to investigate the feasibility of developing surfactant-assisted multiwalled carbon nanotube (MWCNT)-laden lubricant for hybrid aluminum metal matrix composite (h-AMMC)/steel (EN31) pair sliding contact. For the preliminary screening, three grade-I base oils, two SAE grade fully formulated commercial oils, and two types of particle additives are used for the tribological investigation. Based on the detailed pilot study, a suitable grade of base oil (SN500), a fully-formulated commercial oil (SAE 20W50) and a solid particle additive (MWCNT) are finalized for the comprehensive tribological investigation. An amphiphilic surfactant, Sorbitan mono-oleate (SPAN 80) is added to MWCNT-in-oil dispersion to functionalize the MWCNT particles. For better insight of the lubrication and friction-wear mechanism, thermophysical properties of prepared suspensions and characterization of the worn-out surfaces of h-AMMC is carried out using various techniques such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. The study reveals some interesting insights on the performance of MWCNT-laden lubricants in the presence of surfactant, which might be connoted for the future development of the lubricants to be used in the industrial applications.

Experimental analysis of tribological performance of palm oil blended with hexagonal boron nitride nanoparticles as an environment-friendly lubricant

Expanded worries about the ecological harm brought about by mineral oil-based lubricants have made a developing worldwide trend of advancing vegetable oil as base oil. Along these lines, this paper presents the tribological performance of palm oil blended with hexagonal boron nitride (hBN) nanoparticles as an environment-friendly lubricant. The hBN nanoparticles were 70 nm and were blended with the palm oil at varying concentrations that ranged between 0 and 0.5 vol.%. The samples were blended by using the sonication technique, with the help of an ultrasonic homogenizer. Thereafter, the tribological test was conducted using a four-ball tribometer as indicated by engineering standard testing method (ASTM D4172-94). The surface morphology and chemical composition of the worn surfaces were observed using the scanning electron microscopy (SEM) installed with energy-dispersive X-beam spectroscopy (EDX). Results showed that when hBN nanoparticles were blended with palm oil, the unsteady-state coefficient of friction (COF) was promptly changed to a steady-state condition during the running-in period. However, the higher concentration of hBN nanoparticles causes higher COF. Furthermore, 0.1 vol.% of the hBN nanoparticles in palm oil exhibited lower COF and wear rate compared with the palm oil alone and commercially available engine oil SAE 15W40.

Evaluation of physicochemical and tribological properties of chaulmoogra (Hydnocarpus wightianus) oil as green lubricant base stock

Due to environmental concerns, natural oils are increasingly being used as an alternative to mineral oil-based products such as lubricants. However, the use of edible oil for industrial application adversely affects their availability for edible purposes. Chaulmoogra oil is a non-edible oil obtained from the seeds of chaulmoogra tree that grows in wastelands. The fatty acid constituents of vegetable oils determine their properties. Presence of long-chain cyclic fatty acids like chaulmoogric acid, hydnocarpic acid and gorlic acid distinguishes chaulmoogra oil from other oils. Research on how cyclic fatty acids influence the properties of vegetable oils and affect their efficacy as base oils for lubricants is scarce in the literature. This paper presents a preliminary evaluation of the physicochemical, viscometric, oxidative and tribological properties of chaulmoogra oil as a lubricant base stock. Gas chromatography–mass spectroscopy, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods were used for structure elucidation. The viscometric analysis was conducted by using Brookfield viscometer. The tribological performance was evaluated by a four-ball apparatus as per ASTM D4172-94. Thermal and oxidative stabilities were evaluated by thermogravimetric/differential thermal analysis in nitrogen and oxygen environments. Pour point was assessed by ASTM D97 method and differential scanning calorimetry. Chaulmoogra oil has a viscosity of 9.2 cSt at 100 ℃ and a viscosity index of 166. Though the coefficient of friction was better than a commercial lubricant of similar viscosity range (SAE 20W40), the wear scar diameter was comparatively higher. Addition of antiwear additive zinc dialkyl dithiophosphate showed considerable improvement in the wear performance of chaulmoogra oil. Chaulmoogra oil showed a high pour point value around 15 ℃ which needs to be improved by appropriate pour point depressants. Environmental advantage, coupled with non-edible nature of chaulmoogra oil, makes it an excellent base stock for lubricants.

Reduction of Harmful Emissions from Domestic Power Generator Usage in Nigeria -A Tribological Approach

Worldwide concern for the release of harmful emission from Internal Combustion (IC) engines requires the optimization of the quantity of fuel used, types of fuel blend used and type of lubrication utilized. In Nigeria, the electrical power requirements of many households rely more on alternative sources such as Solar systems and fossil fuel-powered generators. The use of these generators is known to produce exhaust fumes that are harmful to humans and the environment. This study investigated the effect of using two different commercially available lubricating oils for gasoline-fueled power generators for domestic applications in comparison to used oils. These are SAE 40 and SAE 20W50. The effect of Boron additive on the two oil brands and used oils (or aged oils) at different speeds on emission from the exhaust stream from the generator was investigated. This is to provide a better understanding of the behavior of Boron additive with SAE 40, SAE 20W50, and aged oils. The study also compared results of torque and emission measurements from oils containing boron to oils without the Boron additives at different speeds. The instruments used to carry out the measurement are a digital tachometer, torque meter (contact type), and 5-gas exhaust analyzer. Results from this study indicated a general decrease in torque with increased speed for all the lubricating oils. This is in agreement with the results of similar studies on torque outputs from IC engines with increasing speeds. However, oils lubricated with Boron additives minimized this loss at a different speed more in SAE 20W50, SAE 40 than in used oils. Carbon monoxide emission from these results indicated that generators lubricated by aged oils are highest at all speed ranges irrespective of Boron additive inclusion. Cleanliness from a gasoline-powered generator is possible if Boron additive is added to lubricating oils. The concentration of NOx emission was found to rise considerably only when operated at the highest speed for aged oils. The results of this study indicated that tribofilms formed by boron-containing oils played a role in preventing torque reduction or power loss and CO emissions from power generators for domestic use. This behavior was attributed to the friction-reducing boric acid and wear resistance borate glass contained within the trilayer. However, tribofilms formed by used oils on tribological parts of the engine gave poor torque reduction results in comparison to that provided by fresh oils. This indicated that when lubricating oils in power generators used in homes are aged beyond the recommended interval for replacement, substantial power loss and harmful emissions are released to the surroundings.

Study of temperature dependent viscosity of different types of engine used oils

The article presents a study on the change in kinematic viscosity with the temperature for three samples of synthetic used oil (SAE 5W-30). Samples were taken after a 10,000 km run on the occasion of periodically changing oil from three engines with close cylindrical capacities (one diesel engine – VW 1.9 TDI, one gasoline engine – Audi 1.8 Turbo and one spark engine – Audi 1.8 Turbo, working with GPL). Comparatively, viscosity measurements were made for the same oils before being introduced into the engines. The kinematic viscosity was measured experimentally using the Brookfield viscometer from 5 to 5 degrees Celsius. To eliminate the errors, the measurements were made under the same conditions for all samples, being repeated three times, the values taken into consideration for a given temperature being made up of averages of the three measurements.

Improving the tribological characteristics of a lubricating oil by nano sized additives

The objective of this work was to study the influence of nanoparticle additives on the lubrication characteristics of engine oil. Three types of nanoparticles viz. hexagonal boron nitride (h-BN), Tungsten disulphide (WS2) and graphite of same size were used as additives in the lubricant SAE 20W50 on a tribo-pair consisting of EN8 steel disk and AISI 52100 steel ball. Friction and wear tests were conducted under boundary lubrication condition on universal tribometer equipped with high resolution piezo load sensor. Raman spectroscopy was used for characterization of worn out surface of EN8 steel disk. It was observed in this study that nanoparticles of h-BN as additive to the lubricant were most effective in comparison to nanoparticles of WS2 and graphite in reducing coefficient of friction (COF) and wear.

Viscosity of Mineral Oil Diluted by Biodiesel Methyl Esters: Methods for Mixture Predictions and Small Samples after Tribometer Testing

The use of biodiesels in internal combustion engines leads to tribology concerns because significant oil dilution occurs when biodiesels leak into the oil pan. Dilution by biodiesels may substantially alter oil lubricity and lead to reduced viscosity, which produce tribological changes on engine materials. It is also possible that such oil-biodiesel mixtures undergo further viscosity decreases when subjected to the high temperatures and high contact pressures typical of internal combustion engine boundary lubrication. This research presents new methods to test viscosity reductions because of biodiesel addition in mineral oil and to assess prediction of mixture viscosity considering the chemical breakdown of biodiesel. The results of dynamic viscosity versus dilution rates are presented for small after-tribometer-testing samples of SAE 15W40 mineral oil diluted by four biodiesels (from canola, peanut, and soybean and chicken fat oil). The small sample remaining after tribometer-testing required an ad-hoc method, the suitability of which is discussed; large viscosity decreases in a range of about 70 to 95 % were observed for after tribometer testing of the mixtures. Preliminary data of viscosity versus temperature also are presented for the mineral oil diluted by increasing fractions of different biodiesels and by six pure fatty-acid methyl esters (methyl-oleate, -palmitate, -linoleate, -laurate, -myristate, and -stearate, which are typical components of biodiesels), and they are discussed to explain tribological properties of such mixtures. The results suggest that the viscosity of commercial biodiesels blended in oils could not be fully explained by assuming the former as mixtures of pure methyl esters, which is consistent with the previous experimental data on their tribological effects.

Многофункциональное масло для наземной военной техники армии США

The U.S. Army has a desire to consolidate multiple MIL specification fluids into a single specification, or Single Common Powertrain Lubricant (SCPL) program. This program is seeking to develop an all-season (arctic to desert), fuel-efficient, multi-functional powertrain fluid with extended drain capabilities and designed to consolidate multiple military lubricant specifications into a single product, or single specification. This paper covers the long term field demonstration programs of the SCPL conducted three locations, representing basic, arctic, and desert climate conditions respectively. Overall the field demonstration for all three locations was considered successful. Real world military vehicle operation using SCPL did not show any differences from currently fielded MIL-PRF-2104 and MIL-PRF-46167 products. In addition, the durability of the SCPL over the one and two year test durations showed that the SCPL is capable of extended drain intervals than the current annual oil change recommendations. These results confirms that the SCPL is a drop in replacement, and is providing improved overall performance compared to currently fielded products. The use of low viscosity engine oil was shown to have a significant impact on fuel consumption: the difference between the current MIL-PRF-2104H SAE 15W-40 grade and the best experimental fluid had an improvement of 1.66% over the test cycle.

Investigations of the Friction Losses of Different Engine Concepts. Part 2: Sub-Assembly Resolved Friction Loss Comparison of Three Engines

In this work, friction loss investigations and comparisons of three different four-cylinder engines for passenger car applications are presented, using a recently developed combined approach. By merging extensive experimental with reliable and predictive journal bearing simulation results, a sub-assembly-resolved friction loss analysis of the piston group, crankshaft journal bearings and valve train is conducted for all three engines. The engines have been chosen individually based on their specific power output and crank train geometry. The measurement program covers a wide range of corresponding engine operation points (identical speed, load and thermal boundary conditions). In addition, the investigations are carried out for different engine media supply temperatures ranging from 70 ∘ C to 110 ∘ C for a comprehensive consideration of the friction losses at reduced lubricant viscosity. For reasons of comparability, all investigations conducted in this work have been carried out using the same modern SAE 5W30 lubricant. This is done to exclude influences from different lubricant properties which may have significant effects on the tribological behaviour of the engines’ sub-assemblies. While the diesel engine showed a friction reduction potential over the entire engine operation range when increasing the engine media supply temperatures, the gasoline engines showed a different behaviour. For the gasoline engines, disadvantages arise especially at low engine speeds. By using the developed combined approach, it was possible to assign mixed lubrication regimes at the valve train systems and at the piston groups.

Tribological Enhancement Features of Various Nanoparticles as Engine Lubricant Additives: An Experimental Study

This study presents tribological enhancement properties of 40–80 nm copper (II) oxide (CuO, nanopowder, ~ 50 nm, 99.9% trace metal basis), copper iron oxide (CuFe2O4, nanopowder < 100 nm, 98.5% trace metal basis), and copper zinc iron oxide (CuZnFe2O4, nanopowder < 100 nm, 99.5% trace metal basis) nanoparticles incorporated (0.1 wt%) in SAE 5W-40 engine lubricant (base oil). Friction and wear evaluations were performed on the sample discs (62–65 HRC, 100 Cr6 steel) using pin-on-disc tribotester. The samples were immersed in the base oil and the nano-oil (oil with each nanoparticle) ambients one after another. Stribeck parameter was analyzed to determine the effects of oil bath temperature and pin-sliding speed on friction and wear within different lubrication regimes. Due to excess increment in an average coefficient of friction (ACOF) above the nanoparticle concentration of 0.1 wt%, the aforementioned amount was used for all experiments. The physical structure of the nanoparticles was examined via scanning electron microscopy and atomic force microscopy analyses were conducted to observe the topography of the worn surfaces. Thermogravimetry (TG)–differential scanning calorimetry measurements were also carried out in order to determine the nanoparticle accumulation on the worn surfaces (thermal stability) and to have an idea about probable surface chemical decomposition. A maximum reduction of 50.8% in ACOF was observed for 5W-40 + CuZnFe2O4 suspension under the temperature of 40 °C and sliding speed of 1 m/s. Furthermore, minimum surface roughness was also determined for the sample processed in 5W-40 + CuZnFe2O4 under the temperature of 70 °C and sliding speed of 0.5 m/s.

Study of the lubricating properties of hybrid liquid paraffin with TiO2 and CuO as nano-additives for engine oil application

Mineral based paraffin oil (L14480) lubricant finds it difficult to give optimum characteristics for modern engine application. In this work, possibility of hybrid paraffin oil which consists of paraffin oil (PO) and sesame oil (SESO) in equal proportions to be used for engine oil application is investigated. Properties of hybrid paraffin oil and SAE 20W40 were estimated and compared. Estimation of thermal characteristics of hybrid paraffin oil shows it have comparable properties with SAE 20W40. Low viscosity characteristics of hybrid paraffin oil can be improved by addition of EVA particles. Addition of TiO2 and CuO nanoparticles shows enough improvement in tribological properties of hybrid paraffin oil. Poor oxidative stability of hybrid paraffin oil can be improved by addition of butylated hydroxytoluene (BHT).

Improvement in frictional behaviour of SAE 15W-40 lubricant with the addition of graphite particles

The present paper discusses the use of graphite particles in the lubricant for enhancing the friction properties of lubricant. Graphite particles were produced using the ball milling methods and mixed with multi-grade SAE 15W-40 lubricating oil using a magnetic stirrer and ultrasonicator. The graphite mixed lubricant was tested for its frictional behaviour using a linear reciprocating tribometer. Experiments were performed at three load values with constant stroke length and frequency. It is observed that graphite mixed lubricant resulted in reduction in coefficient of friction (COF) values. For the considered operating parameters, there is 33–36% reduction in the COF values. The overall temperature generation during the testing was also low for the graphite mixed lubricant testing.

The statistical investigation of multi-grade oil based nanofluids: Enriched by MWCNT and ZnO nanoparticles

In this experiment, for the first time, nanoparticles were suspended in the 5W30 base oil as a suitable oil for mild climates. Statistical investigation of the temperature effect, volume fraction (VF) and shear rate (SR) for viscosity of MWCNT–ZnO (20%–80%) / 5W30 nanofluid and a new experimental three variable correlation are presented for engineering applications with non-Newtonian fluids as their working fluids. In fact, the effect of SR on viscosity changes is considered for the first time for viscosity prediction of SAE 5W30 engine oil. Viscosity tests were carried out at temperatures between 5–55 °C to check the enriched oil behavior at low temperatures and 0.05%–1% VFs considering economic limitations. The addition of nanoparticles to the 5W30 base fluid at all temperatures increased viscosity. Moreover, the viscosity sensitivity less than 2% on VFs less than one, indicates that this nanofluid is suitable to use in various engineering systems. Low level of sensitivity of proposed nanofluid is a suitable condition for using this nanofluid in industries with a high level of risks of human mistakes.

Curve-fitting on experimental thermal conductivity of motor oil under influence of hybrid nano additives containing multi-walled carbon nanotubes and zinc oxide

Hybrid nanofluids has been attracted lots of attention due to simultaneous take advantage of the properties of two or more kinds of nanoparticles in the base fluid. Carbon Nanotubes (CNTs) are utilized widely attached to metal oxide nanoparticles due to significant thermal characteristics. This study aims to assess experimentally the thermal conductivity of the hybrid nanofluid of Zinc Oxide (ZnO) and Multi-Wall CNT (MWCNT) in Engine oil (SAE 10W40). The influences of nanoparticles concentration as well as fluid’s temperature are evaluated. The experiments performed at the temperature between 25 oC and 50 oC and nanoparticles volume fraction from 0.05 to 0.8 %. The experimental results showed that a higher ratio of nano-lubricant thermal conductivity is achieved for a higher volume fraction and temperature of nanoparticles. According to the absence of an exact relationship to determine the thermal conductivity of ZnO-MWCNT/Engine oil, a correlation is developed based on the test measurements presented in terms of volume fraction and temperature using a curve-fitting method. A deviation analysis is also performed on the ratio of thermal conductivity achieved from the developed correlation and experimental data showing a reasonable agreement

Friction and Wear Behavior of 1-Octyl-3-methylimidazolium Lactate Ionic Liquid as Lubricant in Steel–Steel Contacts

The friction and wear behavior of 1-octyl-3-methylimidazolium lactate ionic liquid (L-L108) between steel surfaces was investigated in ball-on-disc sliding friction tests. At an applied load of 5 N and rotating speed of 200 rpm, the friction coefficient of L-L108 was measured as 0.023, which is about one third and one fifth the values of ionic liquid L-P108 (0.068) and SAE 10W-40 engine oil (0.107), respectively. Studies on wear surfaces show that the wear morphology improved when lubricated with L-L108. In addition, the anticorrosion property of L-L108 is better than that of L-P108. Possible mechanisms behind these encouraging performances of L-L108 are discussed and it was found that the interactions between L-L108 and steel surfaces are possible reasons for the reduction in friction coefficient and the improved wear morphology.

Specifications of Heavy Diesel Lubricating Oil Improved by MWCNTs and CuO as Nano-additives

In this investigation, the properties of heavy diesel lubricants were enhanced by adding the nano-additives. The purpose of this research is verifying the enhancement of the rheological and thermal characteristics of the lubricating oils by adding the nano-additives, in order to upgrade to the highest level for performance lubricant in the system. The SAE 15W40 (Oil parent) was mixed with two types of nanomaterials (MWCNTs and CuO) at four various concentrations by (0.1, 0.2, 0.5, and 1 % wt.) to prepare the nano-lubricants, studying and comparing their properties with parent lubricants. The results indicated that the thermal conductivity values of (OilMWCNTs) and (OilCuO NPs) at 1 wt. % concentration of both additives increased by 23%, 15.3% respectively. Also, the flash point of both nano-lubricants comparison with parent oil increased by (19.54%, 15.9%) respectively. It was concluded that (OilMWCNTs) showed higher lubricant’s specification than (OilCuO NPs) due to the high surface area of MWCNTs. Hence, the operating properties of lubricating oil much enhanced when scattered the carbon nanotubes and copper oxide NPs.

Effect of Castor oil as Biolubricant on Tribological Characteristics of EN31 Steel Experimentation and Validation

The main aim of this study to investigate the effect of castor oil blended with lube oil (SAE20W40), on Tribological characteristics of bearing material (EN31), using Ball on Disk Tribotester. The disc test material was EN31 Steel, 165 mm diameter and Test ball material was EN31 Steel, 10 mm Diameter. The test was performed at temperature of 45oC with different loads and different rotating speeds(Test duration of 3600 sec.).The test was conducted in wet conditions using the ASTM G99 Wear and Friction test procedure. Experiments were conducted based on the plan of experiments generated through Taguchi's technique. A L16 Orthogonal array was selected for analysis of data. The petroleum based lubricant used for this experiment was SAE 20W40 and contaminated with a various blends like 0% 10%, 20%, 30% of castor oil. The lubricant is characterized by viscosity using viscometer. From the experimental result, it is found that the wear is increased with increase in loads, increased in speed and sliding distance. The overall result of this experiment reveals that the wear for various blending percentage were different, moreover the wear for 10% castor oil blending were almost identical with base lubricant. This blend can be used as lubricant for piston pump application, which is environmental friendly in nature and would help to reduce use of petroleum based lubricants substantially.

Friction and wear behavior of karanja oil derived biolubricant base oil

This work deals with the tribological performance of karanja oil trimethylolpropane ester (KOTMPE) biolubricant base oil for its probable application as automotive lubricant. The biolubricant was synthesized by transesterification of karanja oil methyl ester with trimethylolpropane (TMP) under acid catalyst. The study was made with Ducom TR30L four-ball tester at 1200 rev min−1 speed and 75 °C temperature over 60 min duration under normal loads of 15 kg and 40 kg as per ASTM D 4172-94 A and B standard test method. Principal results at two loads are given here: Coefficient of friction (CoF) 0.100 and 0.042, wear scar diameter (WSD) 0.30 mm and 0.44 mm, flash temperature parameter (FTP) 80.932 and 126.249, and thermal energy (TE) 0.054 J and 0.060 J, respectively. The study found that KOTMPE has lowest CoF than any vegetable oil, TMP ester or commercial lubricant. Similarly, the WSD was lowest among all the vegetable oil based lubricants and was at par with SAE 20W-50 and SAE 40 commercial lubricants. FTP was better compared to any vegetable oil or TMP ester. Finally, the energy efficiency of KOTMPE was better than that of other vegetable oils, TMP esters and mineral lubricants. The synthesized ester demonstrated the outstanding performance in terms of friction and wear characteristics along with high thermal stability and energy efficiency worthy of comparison with multiple lubricating products reported by different research groups in available literature during last two decades.