Search results

1 – 10 of over 1000
To view the access options for this content please click here
Article
Publication date: 3 June 2014

Alicja Laber

The purpose of this paper is to present the results of research into using an additive to SAE 15W/40 engine oil during operation and its influence on lubricating…

Abstract

Purpose

The purpose of this paper is to present the results of research into using an additive to SAE 15W/40 engine oil during operation and its influence on lubricating properties (normalised tests) on weld point Pz, non-seizure load Pn, load wear index Ih and on seizure load Pt. The friction pair consisted of a group of four balls and the tested lubricant. Moreover, the author tested the influence of an additive to engine oil (non-normalised tests) on tribological properties, including friction force, wear and the temperature of friction area for the C45 steel/210Cr12 steel friction joint. She also determined the influence of an additive to engine oil on the formation of the operating surface layer. The research results helped to build the model of the boundary layer that was formed as a result of adding an additive to engine oil.

Design/methodology/approach

The lubricant properties of engine oil and engine oil to which an additive was added during operation were determined according to PN-76/C-04147. The following are the indexes of lubricant properties: weld point Pz, load wear index Ih, non-seizure load Pn, seizure load and average scar diameter. The Pz, Pn and Ih indexes were determined at abruptly increasing load to the moment of welding of the friction pair. The Pt index was determined at the increasing load of the friction pair from 0 to 800 daN at the speed of 408.8 N/s. The tests of tribological properties (friction force, wear and the temperature of friction area) were conducted for the C45/210 Cr12 friction pair in the presence of a lubricant and a lubricant with an additive.

Findings

The modification of SAE 15W/40 engine oil with the additive added during operation resulted in improved indexes of lubricant properties Pz, Pn, Ih and Pt and average scar diameter. The boundary layer for the modified oil breaks after a longer time and at lesser friction force. The modification of the engine oil reduced the wear of the friction pair. After the friction process, element composition in the surface layer of the wear trace and its distribution were determined in relation to applied lubricants. A significant amount of sulphur, phosphorus and oxygen, as well as an insignificant amount of copper, was observed in the wear trace after the friction process in the presence of the lubricant medium. The distribution of elements in the wear trace when the engine oil with the additive was used is steady in the wear trace and outside it. Some sulphur, phosphorus and chlorine were found in the wear trace.

Originality/value

The results of tests on tribological properties (non-normalised tests) confirmed the positive affect of the additive to engine oil on lubricant properties (normalised tests). The modification of the engine oil caused reduced friction force and the reduced wear of the friction pair. The reduction of friction force and wear was the result of the formation of the surface of a greater amplitude density of unevenness tops in the friction process. Moreover, the operating surface layer, created in the friction process when the additive was added to the engine oil, had greater load participation at 50 per cent C. This operational surface layer improved tribological properties, i.e. it reduced value of friction force and wear. The test results were used to build a model of the boundary layer created as a result of the additive added to engine oil.

Details

Industrial Lubrication and Tribology, vol. 66 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 9 March 2015

C. B. Mohan, K. Venkatesh, C. Divakar, K. Gopalakrishna, L. Murali and K. G. Lakshminarayana Bhatta

The paper aims to address the formulation of zirconium and oxalicum additive-based lubricants for use in slide ways to meet the demands of high positioning exactness based…

Abstract

Purpose

The paper aims to address the formulation of zirconium and oxalicum additive-based lubricants for use in slide ways to meet the demands of high positioning exactness based on reduction in stick–slip and coefficient of friction over a wide speed range and compares the same with commercially available lubricant.

Design/methodology/approach

An investigation into the frictional properties and stick-slip behavior of lubricating oil is carried out using linear reciprocating tribometer and correlated with ultraviolet spectroscopic analysis.

Findings

It is observed that these transition metal additive compounds support in increasing the flexibility of the molecular chains leading to improved lubricity.

Originality/value

The lubricant additives considered for the current study are based on transition metals zirconium and oxalicum. It is observed that these additive compounds support in increasing the flexibility of the molecular chains, leading to improved lubricity.

Details

Industrial Lubrication and Tribology, vol. 67 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 1 March 1963

P.H. MOLYNEUX

THE BENEFIT of lubricants and of additives an “lubricant modifiers” has been known for centuries. For example, animal fat was used to reduce friction and thus squeaking…

Abstract

THE BENEFIT of lubricants and of additives an “lubricant modifiers” has been known for centuries. For example, animal fat was used to reduce friction and thus squeaking, of Roman chariot wheels sulphur was employed to aid the machining of iron during the Industrial Revolution, The type of additives which will be discussed in this paper are, however, of more recent origin and are complex chemical compounds which are added in controlled quantities to lubricating fluids to enhance or modify their specific natural properties.

Details

Industrial Lubrication and Tribology, vol. 15 no. 3
Type: Research Article
ISSN: 0036-8792

To view the access options for this content please click here
Article
Publication date: 3 May 2011

M. Husnawan, H.H. Masjuki and T.M.I. Mahlia

The purpose of this paper is to study the effect of palm olein, amine phosphate and 4‐nonyl phenoxy acetic acid (NPAA) added to a commercial lubricant in terms of…

Abstract

Purpose

The purpose of this paper is to study the effect of palm olein, amine phosphate and 4‐nonyl phenoxy acetic acid (NPAA) added to a commercial lubricant in terms of tribological properties such as wear and coefficient of friction.

Design/methodology/approach

A tribological study on the lubrication performance of a lubricant‐based palm oil (PO) containing anti‐wear and antioxidant combined corrosion inhibitor additive was carried out using a universal sliding wear machine. In this experiment, amine phosphate and NPAA were selected as additive to be mixed with PO (palm olein) in several concentrations and commercial lubricant 20W‐50 for the tests. Various PO blended samples with additional 1 and 3 percent additive were used in this study. The experiments were performed under 252 rpm sliding speed for 2 h where the oil temperature reached 100°C.

Findings

The analysis showed that the average wear coefficient and the mean wear scar diameter (MWSD) which is normalized to the 1.4 KPa water pressure generates lower values for the PO containing additives than 100 percent PO, commercial lubricant and their blended. The coefficients of friction and wear were also lower for the samples with additives compared to other. To consolidate the result, viscosity of used samples is checked and shows the additives improved the viscosity stability. Finally, the overall study concluded that PO‐added additives have the potential to be one of the ingredients in effective lubricant oil.

Research limitations/implications

The paper is limited to findings based on a Universal Sliding Machine Test under certain conditions. The test has been conducted on the basis of three types of chemical compounds (palm olein, amine phosphate and NPAA) which are designed as a combination of anti‐wear and antioxidant additive. Wear and friction characteristics of the lubricant with and without these additives are analyzed in this paper. However, the film formation and microstructure analysis of the lubricated materials are excluded in this study.

Practical implications

This paper shows a significant reduction of average wear rate and friction coefficient when palm olein and additive added to the lubricant compared to pure commercial lubricant. In terms of wear scar diameter (WSD), with additional palm olein and additive produces lower WSD which is under the standard limit of diesel lubricity. These results have confirmed that by using palm olein as renewable component together with amine phosphate and NPAA additive would improve lubrication performance as well as improves biodegradability of the lubricant.

Originality/value

This paper emphasises the advantages of synthetic additives that are derived from renewable resources. Since environmental issues are now stringent, many lubricant industries have focused on environmentally friendly lubricant and researches on this particular area become important. The presented tests have been carried out in the above area which is close to those applied in lubricant industry. Thus, the results are reliable and could be very useful both for lubricant designers and the researchers of lubricant and additive formulation.

Details

Industrial Lubrication and Tribology, vol. 63 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here

Abstract

Purpose

There is a continuous drive in automotive sector to shift from conventional lubricants to environmental friendly ones without adversely affecting critical tribological performance parameters. Because of their favorable tribological properties, chemically modified vegetable oils such as palm trimethylolpropane ester (TMP) are one of the potential candidates for the said role. To prove the suitability of TMP for applications involving boundary-lubrication regime such as cam/tappet interface of direct acting valve train system, a logical step forward is to investigate their compatibility with conventional lubricant additives.

Design/methodology/approach

In this study, extreme pressure and tribological characteristics of TMP, formulated with glycerol mono-oleate (GMO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyldithiophosphate (ZDDP), has been investigated using four-ball wear tester and valve train test rig. For comparison, additive-free and formulated versions of polyalphaolefin (PAO) were used as reference. Moreover, various surface characterization techniques were deployed to investigate mechanisms responsible for a particular tribological behavior.

Findings

In additive-free form, TMP demonstrated better extreme pressure characteristics compared to PAO and lubricant additives which are actually optimized for conventional base-oils such as PAO, are also proved to be compatible with TMP to some extent, especially ZDDP. During cylinder head tests, additive-free TMP proved to be more effective compared to PAO in reducing friction of cam/tappet interface, but opposite behavior was seen when formulated lubricants were used. Therefore, there is a need to synthesize specialized friction modifiers, anti-wear and extreme pressure additives for TMP before using it as engine lubricant base-oil.

Originality/value

In this study, additive-free and formulated versions of bio-lubricant are tested for cam/tappet interface of direct acting valve train system of commercial passenger car diesel engine for the very test time. Another important aspect of this research was comparison of important tribological performance parameters (friction torque, wear, rotational speed of tappet) of TMP-based lubricants with conventional lubricant base oil, that is, PAO and its formulated version.

Details

Industrial Lubrication and Tribology, vol. 70 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 9 April 2018

Yanhong Li, TianTian Liu, Yujuan Zhang, Pingyu Zhang and Shengmao Zhang

The purpose of this paper is to study the tribological properties of Cu nanoparticles (NPs) as lubricant additives in three kinds of commercially available lubricants.

Abstract

Purpose

The purpose of this paper is to study the tribological properties of Cu nanoparticles (NPs) as lubricant additives in three kinds of commercially available lubricants.

Design/methodology/approach

A four-ball machine is used to estimate the tribological properties of Cu NPs as lubricant additives in three kinds of commercially available lubricants. Three-dimensional optical profiler and electrical contact resistance are evaluated to investigate the morphology of the worn surfaces and the influence of Cu NPs on tribofilms.

Findings

Wear tests show that the addition of Cu NPs as lubricant additives could reduce wear and increase load-carrying capacity of commercially available lubricants remarkably, indicating that Cu NPs have a good compatibility with the existing lubricant additives in commercially available lubricants.

Originality/value

The tribological properties of Cu NPs as lubricant additives in three kinds of commercially available lubricants were investigated in this paper. These results are reliable and can be very helpful for application of Cu NPs as lubricant additives in industry.

Details

Industrial Lubrication and Tribology, vol. 70 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 2 October 2020

Tong Yu, Peng Yin, Wei Zhang, Yanliang Song and Xu Zhang

The amount, type and addition conditions of additives of lubricants should be continuously adjusted to obtain appealing performance. To obtain the optimal pretreatment…

Abstract

Purpose

The amount, type and addition conditions of additives of lubricants should be continuously adjusted to obtain appealing performance. To obtain the optimal pretreatment parameters and reduce the cost of time-consuming experiments, the purpose of this paper is to establish an optimal back propagation neural network (BPNN) model combined with genetic algorithm (GA) in this work.

Design/methodology/approach

Using trimethylolpropane trioleate as the base oil and three types of phosphorus compounds as additives, 25 sets of lubricant formulas were designed regarding lubricant performances of average friction coefficient, average spot diameter, disk wear volume and extreme pressure. The data set was used for training and learning of BPNN and then combined with GA to optimize BPNN with continuously optimization by adjusting various parameters.

Findings

Comparing prediction data of BPNN with actual test data, correlation coefficients were above 90%, indicating that the model could accurately predict the performance of lubricants. When combined with GA, all performance errors were less than 5%, indicating that BPNN could be optimized by GA to obtain an accurate combined model for prediction of lubricant performance. The best additive formula with excellent performances was obtained from the BPNN–GA model.

Originality/value

This work developed a new method to study lubricant compounding. The combined model was expected to provide a theoretical basis and guidance for the compounding optimization of lubricant additives with high efficiency and low cost and to expand the scope to practical applications.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0165/

Details

Industrial Lubrication and Tribology, vol. 73 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 12 March 2018

Maheswaran R. and Sunil J.

The optimal performance of the machinery is based on lubricants that require frequent monitoring and the analysis of characteristics such as chemical content…

Abstract

Purpose

The optimal performance of the machinery is based on lubricants that require frequent monitoring and the analysis of characteristics such as chemical content, contamination and viscosity. The application of nanoparticles dispersed lubricant in tribology has received remarkable attention in recent years. This paper aims to investigate the tribological properties of SN500 grade lubricating oil containing garnet nanoparticles.

Design/methodology/approach

In this study, 45-nm-sized garnet particles are ultrasonically dispersed in SN500 grade base lubricant oil. The effects of viscosity and additive concentration on tribological properties are investigated using a four-ball tester.

Findings

Rolling, reinforcing and film-forming behaviour of dispersed nano-sized garnet additives in the rubbing zone were investigated using scanning electron microscopy equipped with energy dispersive spectroscopy. The results indicate that the garnet additives can improve the wear resistance and resistance to relative motion and decrease the friction coefficient of rubbing steel interface by surface polishing and formation of tribo-film containing Si, C and Mn.

Originality/value

Because of the complex two-phase solid–liquid mixture, there are still limited physical understandings of the friction and wear reduction mechanisms. Therefore, the present research was undertaken to interpret the possible phenomena.

Details

Industrial Lubrication and Tribology, vol. 70 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 10 August 2015

Dogus Özkan, Hakan Kaleli, Yves BERTHIER and Levent Yüksek

This paper aims to investigate the wear mechanisms, formations and effectiveness of tribofilms of new developed, antiwear additive which is called mercapthocarboxylate…

Abstract

Purpose

This paper aims to investigate the wear mechanisms, formations and effectiveness of tribofilms of new developed, antiwear additive which is called mercapthocarboxylate. The mercapthocarboxylate is a sulphur-based and non-phosphorus additive.

Design/methodology/approach

The effectiveness of the additive was examined through a set of laboratory endurance tests that applied with single cylinder spark ignition engine. Two types of lubricants were used to compare the engine tests which were thiophosphate (ZDDP) containing engine lubricant (phosphorus containing) and mercapthocarboxylate containing non-phosphorus and non-ash crankcase oil. Lubricants were tested under identical operating conditions for 100 hrs. The surfaces of cylinder liner and piston rings were inspected through optical microscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques.

Findings

Catalysis-friendly and sulphur-based mercapthocarboxylate additive can be an alternative antiwear additive package for lubrication oil due to better wear performance when compared to ZDDP.

Originality/value

Sulphur-based mercapthocarboxylate is a new developed antiwear additive and was applied to lubrication oil in this study. This lubrication oil was tested in the real engine environment by using 100-hr engine bench tests.

Details

Industrial Lubrication and Tribology, vol. 67 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 2 May 2008

Ertuğrul Durak, Hakan Adatepe and Aydin Biyiklioğlu

The purpose of this paper is to study the effects of additive on the tribological properties such as friction coefficient and wear loss in the journal bearings during…

Abstract

Purpose

The purpose of this paper is to study the effects of additive on the tribological properties such as friction coefficient and wear loss in the journal bearings during start‐up (or shut‐down) and running‐in periods.

Design/methodology/approach

In this study, fully formulated commercial engine mineral oil (SAE 20W50) and commercial oil additives (3 per cent) added into this oil were tested to determine the tribological performances such as friction coefficient, wear loss and the effect of the additive on protective layers formed on the sliding bearing's surfaces.

Findings

This study presents an experimental procedure for obtaining practical results pertaining to the tribological performance of the journal bearing under running‐in and start‐up or shut down stages. Also, in this study, the authors have attempted to show the linkage between the oil additive and the running conditions such as running‐in and start‐up and shut‐down in effecting performance of the journal bearing. It is well known that one of the roles of an additive is to form a protective layer to reduce friction coefficient in lubricated contacts.

Originality/value

The paper is of value in presenting an experimental procedure for obtaining practical results pertaining to the tribological performance of the journal bearing under running‐in and start‐up or shut down stages.

Details

Industrial Lubrication and Tribology, vol. 60 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of over 1000