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Article
Publication date: 1 June 2004

Hakan Kaleli

The role that lubricating oils play is, first of all, to reduce energy loss and keep the wear and seizure to a minimum, or, in a broader sense, to improve the friction…

Abstract

The role that lubricating oils play is, first of all, to reduce energy loss and keep the wear and seizure to a minimum, or, in a broader sense, to improve the friction characteristics. Resistance to deterioration and prevention of rust development on metals are demanded as secondary functions. The time during which lubricating oil retains its ability to prevent any possible damage to a body in motion should be considered as its lifetime. Many functions that are provided by base oil alone are insufficient; therefore, special additives are dissolved in them. The additives for lubricating oils are of many types, and their functions are diverse and many. Those additives that are used with the purpose of improving friction characteristics are generally called oiliness improvers or friction modifiers. In this study, the protective additive's layers formed on rubbed surfaces of pins, plates and discs were investigated using pin‐on‐disc and reciprocating pin‐on‐plate test rigs. Wear tracks were examined using optical and electron microscopy with X‐ray diffraction analysis.

Details

Industrial Lubrication and Tribology, vol. 56 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 6 May 2020

Ramakant Rana, Qasim Murtaza and R.S. Walia

In this study, the tri-bological behaviour of the un-coated and diamond coated tungsten carbide was evaluated using the pin-on-disc test rig. The same was also tested on a…

Abstract

Purpose

In this study, the tri-bological behaviour of the un-coated and diamond coated tungsten carbide was evaluated using the pin-on-disc test rig. The same was also tested on a lathe machine tool. This paper aims to compare the tri-bological behaviour of coated tungsten carbide pin with un-coated tungsten carbide pin it also correlates the wear obtained from the two machines used.

Design/methodology/approach

Experiments were performed using L8 orthogonal array and results obtained on a pin-on-disc test rig under dry sliding process were optimized through a modern optimization technique i.e. genetic algorithm (GA). The response surface methodology model (L8 orthogonal array) formed the basis for the development of the GA model, which defines the conditions of minimum wear, minimum coefficient of friction and minimum surface roughness for the sliding process of the pin-on-disc test rig.

Findings

Implementation of the heuristic approach for optimization of input parameters for the combination of tool material used for the turning process. The initial approach involves tri-bological testing considering the same combination. The set of experiments further performed, inferred that the results were similar and that the diamond coating enhances the life of the tool.

Originality/value

Successfully synthesized the diamond coating on tungsten carbide tool material. Implantation of the heuristic approach, i.e. GA to tri-bological tests to identify the optimized level of input variables. Experimentation involves the tri-bological testing whose results were confirmed through performing experiments on the lathe machine tool.

Details

World Journal of Engineering, vol. 17 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 7 August 2017

Guangming Chen, Dingena L. Schott and Gabriel Lodewijks

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces…

Abstract

Purpose

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces of bulk-solids-handling equipment. Predicting the sliding wear volume from equipment surfaces is beneficial for efficient maintenance of worn equipment. Recently, the discrete element method (DEM) simulations have been utilised to predict the wear by bulk-solids. However, the sensitivity of wear prediction subjected to DEM parameters has not been systemically investigated at single particle level. To ensure the wear predictions by DEM are accurate and stable, this study aims to conduct the sensitivity analysis at the single particle level.

Design/methodology/approach

In this research, pin-on-disc wear tests are modelled to predict the sliding wear by individual iron ore particles. The Hertz–Mindlin (no slip) contact model is implemented to simulate interactions between particle (pin) and geometry (disc). To quantify the wear from geometry surface, a sliding wear equation derived from Archard’s wear model is adopted in the DEM simulations. The accuracy of the pin-on-disc wear test simulation is assessed by comparing the predicted wear volume with that of the theoretical calculation. The stability is evaluated by repetitive tests of a reference case. At the steady-state wear, the sensitivity analysis is done by predicting sliding wear volumes using the parameter values determined by iron ore-handling conditions. This research is carried out using the software EDEM® 2.7.1.

Findings

Numerical errors occur when a particle passes a joint side of geometry meshes. However, this influence is negligible compared to total wear volume of a wear revolution. A reference case study demonstrates that accurate and stable results of sliding wear volume can be achieved. For the sliding wear at steady state, increasing particle density or radius causes more wear, whereas, by contrast, particle Poisson’s ratio, particle shear modulus, geometry mesh size, rotating speed, coefficient of restitution and time step have no impact on wear volume. As expected, increasing indentation force results in a proportional increase. For maintaining wear characteristic and reducing simulation time, the geometry mesh size is recommended. To further reduce simulation time, it is inappropriate using lower particle shear modulus. However, the maximum time step can be increased to 187% TR without compromising simulation accuracy.

Research limitations/implications

The applied coefficient of sliding wear is determined based on theoretical and experimental studies of a spherical head of iron ore particle. To predict realistic volume loss in the iron ore-handling industry, this coefficient should be experimentally determined by taking into account the non-spherical shapes of iron ore particles.

Practical implications

The effects of DEM parameters on sliding wear are revealed, enabling the selections of adequate values to predict sliding wear in the iron ore-handling industry.

Originality/value

The accuracy and stability to predict sliding wear by using EDEM® 2.7.1 are verified. Besides, this research accelerates the calibration of sliding wear prediction by DEM.

Details

Engineering Computations, vol. 34 no. 6
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 7 March 2008

Ugur Ozsarac and Salim Aslanlar

The aim of this study is to calculate the coefficient of friction of wheel/rail interface in both water lubrication and dry friction conditions.

Abstract

Purpose

The aim of this study is to calculate the coefficient of friction of wheel/rail interface in both water lubrication and dry friction conditions.

Design/methodology/approach

Specimens taken from wheel and rail used in railway transport were exposed to pin‐on‐disc wear testing with 10, 20, 30 and 40 N loads. The disc took the place of the rail and the pin that of the wheel in wear tests, and rain water was fed to the disc/pin interface with a three drops/min speed in wet friction conditions. The coefficient of friction and weight loss values of specimens were determined and types of wear mechanism were characterized.

Findings

It was observed that the friction coefficient decreased in wet sliding experiments, so smaller values were calculated in wet friction conditions than those of dry friction conditions for wheel specimens. However, this decrease was more drastic for rail specimens. Weight and volumetric loss values of rail materials were lower than those of wheel samples.

Originality/value

This study investigates the wet and dry sliding wear characteristics of train wheel‐rail materials.

Details

Industrial Lubrication and Tribology, vol. 60 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 December 1996

Bill Wilson

Outlines the various testing procedures carried out by BICERI, including engine fuel and lubricant testing. Describes the universal wear machine, and explains the three…

Abstract

Outlines the various testing procedures carried out by BICERI, including engine fuel and lubricant testing. Describes the universal wear machine, and explains the three test modes: pin‐on disc, block‐on‐ring and pin‐on‐reciprocating plate.

Details

Industrial Lubrication and Tribology, vol. 48 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 February 2000

Mircea Terheci

Attempts to reveal some of the factors that might cause measurement and evaluation errors in dry sliding. Discusses matters such us “what” and “how” is simulated and “why”…

Abstract

Attempts to reveal some of the factors that might cause measurement and evaluation errors in dry sliding. Discusses matters such us “what” and “how” is simulated and “why” and “what” is really measured and suggests ways to tackle these matters. Presents means of avoiding measurement errors as well as suitable testing procedures. Suggests a strategy of experimental work that encompasses the needs of both pure research and engineering design. It was found that the pin‐on‐disc test largely satisfies the conditions for a good simulation of certain engineering applications while providing a wealth of data for both scientific insight and engineering design.

Details

Industrial Lubrication and Tribology, vol. 52 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 2 September 2014

Ugur Ozsarac, Salim Aslanlar, Faruk Varol and Mehmet Ekici

The purpose of this study was to investigate wear behaviours of brake pads produced from carbon–carbon (C/C) composites in both wet and dry friction sliding conditions…

Abstract

Purpose

The purpose of this study was to investigate wear behaviours of brake pads produced from carbon–carbon (C/C) composites in both wet and dry friction sliding conditions. Carbon is probably the most remarkable element in science and also C/C composites are a family of advanced composite materials. They are the most advanced form of carbon and consist of fibre based on carbon precursors embedded in a carbon matrix. In the present work, wear test specimens were prepared according to the related standards and they were exposed to pin-on-disc wear testing in wet and dry sliding conditions with different loads as 10, 20, 30 and 40 N with 1 m/s constant sliding speed. Wet friction process was conducted on all specimens by means of rain water collected from the nature.

Design/methodology/approach

Pin-on-disc wear test tribology lubrication was used.

Findings

Mechanical and physical property measurements of C/C composite brake pad materials: hardness, modulus of elasticity, density and water absorption capacity. Wear performance of materials were measured as coefficient of friction, volumetric loss and specific wear rate.

Originality/value

C/C composite brake pads are used in railway vehicles. Wear performances of them are very important for safety. In this study, wear behaviours of these materials were investigated not only in dry sliding friction condition but also in wet sliding one. Because safety braking is important in all weather conditions for trains, and we used natural rain water to observe the wet sliding friction behaviour of brake pads. “Water lubrication” is an important aspect mentioned in tribology handbooks.

Details

Industrial Lubrication and Tribology, vol. 66 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 29 March 2019

Gitesh Kumar, Hem Chander Garg and Ajay Gijawara

This paper aims to report the friction and wear characteristics of refined soybean oil (RSBO) blended with copper oxide (CuO) nanoparticles and zinc dialkyldithiophosphate…

Abstract

Purpose

This paper aims to report the friction and wear characteristics of refined soybean oil (RSBO) blended with copper oxide (CuO) nanoparticles and zinc dialkyldithiophosphate (ZDDP) as additives.

Design/methodology/approach

Four different concentrations 0.04, 0.05, 0.1 and 0.2 Wt.% of CuO nanoparticles were added with ZDDP in RSBO. The friction and wear characteristics of lubricants have been investigated on a pin-on-disc tribotester under loads of 120 and 180 N, with rotating speeds of 1,200 and 1,500 rpm in half hour of operating time. The dispersion stability of CuO nanoparticles has been analyzed using ultraviolet visible (UV-Vis) spectroscopy. The wearout surface of pins has been examined by using a scanning electron microscope.

Findings

The results revealed that there is a reduction in the friction and wear by the addition of CuO nanoparticles and ZDDP in RSBO. Coefficient of friction increases at a high sliding speed for RSBO with ZDDP. From UV-Vis spectroscopy, it is observed that 100 ml of oleic acid surfactant per gram of CuO nanoparticles has stable dispersion in RSBO.

Originality/value

The addition of ZDDP and CuO nanoparticles in RSBO is more efficient to reduce the friction and wear in comparison to base oil. The optimum concentration of CuO nanoparticles in RSBO is 0.05 Wt.%.

Details

Industrial Lubrication and Tribology, vol. 71 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 22 June 2010

C. Subramanian and S. Senthilvelan

The purpose of this paper is to understand the influence of reinforced fiber length over material‐plastic energy of deformation, clogging, crystallinity, and correlates…

Abstract

Purpose

The purpose of this paper is to understand the influence of reinforced fiber length over material‐plastic energy of deformation, clogging, crystallinity, and correlates with the friction and wear behavior of polypropylene (PP) composites under multi‐pass abrasive condition. Also to identify wear mechanisms of glass fiber reinforced PP materials under various abrasive grit sizes and normal loads.

Design/methodology/approach

Multi‐pass abrasive wear tests were performed for unreinforced, short, and long glass fiber reinforced PP (LFPP) on a pin on disc machine under three different normal loads and two different abrasive grit sizes for a constant sliding velocity. Measured wear volume was correlated with the plastic energy of deformation by carrying out a constant load indentation test using servo hydraulic fatigue test system. Clogging behavior of test materials was examined with the aid of online wear measurement and wear morphology. Test materials crystallinity was estimated with the aid of X‐ray diffraction investigation and correlated with abrasive wear performance.

Findings

Fiber reinforcement in a PP material is found to improve the plastic deformation energy and crystallinity which results in improved abrasive resistance of the material. Increase in reinforced fiber length is found to improve the material cohesive energy and hence the wear resistance. Reinforcement is found to alter the material clogging behavior under multi‐pass condition. Fiber reinforcement is found to reduce the material coefficient of friction, and increase in reinforced fiber length further reduces the frictional coefficient.

Research limitations/implications

Friction wear tests using pin on disc equipment is carried out in the present investigation. However, in practice, part geometry may not be always equivalent to simple pin on disc configuration.

Practical implications

The paper's investigation results could help to improve the utilization of LFPP material in many structural applications.

Originality/value

Influence of reinforced fiber length over multi‐pass abrasive wear performance of thermoplastic material, and online wear measurement to substantiate clogging behavior is unique in the present multi‐pass abrasive investigation.

Details

Industrial Lubrication and Tribology, vol. 62 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 2 September 2014

Bhanudas Dattatraya Bachchhav, Geeta S. Lathkar and Harijan Bagchi

This paper aims to present a study of frictional characteristics of steel/die steel pair under sliding contact in presence of a set of formulated lubricants. AISI 1010 low…

Abstract

Purpose

This paper aims to present a study of frictional characteristics of steel/die steel pair under sliding contact in presence of a set of formulated lubricants. AISI 1010 low carbon steels, although being strong, are less formable grades of steel and require appropriate selection of lubricants in tribological conditions.

Design/methodology/approach

A total of three mineral-based lubricating blends were formulated for varying concentration of ester. Plan of experiments, based on Taguchi’s analysis technique were performed using dedicated test rig based on “pin-on-disc” principle.

Findings

A correlation was established between additive concentration, sliding speed and pressure with coefficient of friction by multiple linear regression. On the basis of experimental results and S/N ratio analysis, ranking of the parameters has been done. A possible regime of working with such lubricants is also suggested.

Practical implications

Due to voluminous data involved, a few dominant process parameters were taken into consideration for the study.

Originality/value

This paper is highlighting the tribo-effects of additives to render it as suitable lubricant in sliding contact conditions. This paper also suggested an approach for selection of optimum regime of working in the light of “Stribeck Curve” for ester-containing lubricating oils.

Details

Industrial Lubrication and Tribology, vol. 66 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

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