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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

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Article
Publication date: 1 July 2006

Y. Zhang

To develop a fairly different EHL inlet zone analysis for investigating the contact‐lubricant interfacial limiting shear stress effect on line contact EHL film thickness…

Abstract

Purpose

To develop a fairly different EHL inlet zone analysis for investigating the contact‐lubricant interfacial limiting shear stress effect on line contact EHL film thickness in isothermal conditions. This analysis is purposed to give fast and qualitatively correct results.

Design/methodology/approach

A Grubin‐like EHL inlet zone analysis is derived with closed form of the analytical results of the EHL film thickness, the EHL film pressure, the contact‐lubricant interfacial shear stress and the contact‐lubricant interfacial slipping velocity in the EHL inlet zone based on the assumption of the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone. In this analysis, the lubricant is allowed to slip at the contact surface; The inlet contact surface shape is known from results referenced in this paper; The physical condition for the presence of the film slippage is incorporated; The lubricated area is divided into different kinds of film slippage zones where are, respectively, applied different governing equations. Three deterministic equations in this analysis are obtained and solving these coupled equations gives the solutions of the boundaries of the slip zone and the percentage reduction of the central film thickness by the contact‐lubricant interfacial limiting shear stress effect in this EHL.

Findings

Compared with the earlier approaches to the present problem, the present analysis has the advantage of giving fast and qualitatively correct solutions. The results obtained from the present analysis show that the contact‐lubricant interfacial limiting shear stress effect on EHL film thickness is usually strong when the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone is low; This effect can greatly reduce the global EHL film thickness especially in severe operating conditions.

Practical implications

A very useful material for the academic researcher and the engineer who are engaged in the study and measurement of the effect of the contact‐lubricant interfacial limiting shear stress on EHL film thickness and EHL film pressure.

Originality/value

A fairly different EHL inlet zone analysis is originally developed based on the assumption of the contact‐lubricant interfacial limiting shear stress in the EHL inlet zone. The physical condition for the contact‐lubricant interfacial slippage is first incorporated in this analysis. Deterministic governing equations in this analysis are derived and solving these coupled equations gives the final solutions of the present problem. This analysis has the advantage of giving fast and qualitatively correct solutions. It convincible shows the contact‐lubricant interfacial limiting shear stress effect on EHL film thickness and EHL film pressure in the present EHL.

Details

Industrial Lubrication and Tribology, vol. 58 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 24 October 2018

Hui Cen, Ardian Morina and Anne Neville

The purpose of this study is to evaluate the effect of water contamination on ageing of lubricants.

Abstract

Purpose

The purpose of this study is to evaluate the effect of water contamination on ageing of lubricants.

Design/methodology/approach

The viscosity, total acid number and Fourier transform infrared spectrum of a series of lubricants after ageing with water were studied. The tribological performance (friction and wear) of the aged lubricants was also analyzed, followed by X-ray photoelectron spectroscopy analysis on the selected post test samples to study the tribochemical features of the tribofilm.

Findings

The results were also compared with Part I of this study, and it was found that ageing has a different impact on lubricants and tribological performances based on the physical and chemical properties when water is present in the lubricants.

Originality/value

This paper is a continuation of Part I of this study and gives an understanding on the impact of water on the lubricants and related tribological and tribochemical performance.

Details

Industrial Lubrication and Tribology, vol. 71 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 8 October 2018

Binnur Sagbas

The purpose of this paper is to investigate applicability of hexagonal boron nitride (h-BN) powder as a solid lubricant additive in coconut oil and to determine the…

Abstract

Purpose

The purpose of this paper is to investigate applicability of hexagonal boron nitride (h-BN) powder as a solid lubricant additive in coconut oil and to determine the tribological behavior of PEEK rubbed with DIN2080 tool steel, under prepared green lubricating condition.

Design/methodology/approach

In this study, tiribological performance of PEEK against the DIN2080 tool steel is investigated with green lubricant. Coconut oil was used as green lubricant and 4 per cent wt. h-BN powder was added as lubricant additive into the coconut oil. Reciprocal pin-plate tribological test were applied under dry, coconut oil and coconut oil+h-BN lubrication condition. Friction coefficients were recorded and wear behavior of the samples investigated by mass loss measurement and topographical inspection of wear track by optical profilometer.

Findings

Using coconut oil as lubricant provided 80 per cent reduction of friction coefficient and 33.4 per cent reduction of wear rate. Addition of h-BN into the coconut oil provide 84 per cent reduction of friction coefficient and 56 per cent reduction of wear rate. The results showed that vegetable oil is promising lubricant for sustainable manufacturing. h-BN serves to increase lubricant performance and decrease wear of the surfaces.

Practical implications

Petrochemical lubricants are one of the major sources of environmental pollution and health hazards. Development and use of environmental and health friendly lubricants support sustainability and reduce wear, friction and energy consumption. With this consciousness, recent studies have focused on green tribology and green lubricants such as vegetable oils, ionic liquid bio-lubricants and bio-based polymers.

Originality/value

In literature study coconut oil was proposed as green lubricant while h-BN powder was proposed as solid lubricant. However, applicability of h-BN powder in coconut oil has not been explored yet. Moreover, wear and friction property of PEEK material with DIN 2080 tool steel pair surface has not been studied yet with green lubricants.

Details

Industrial Lubrication and Tribology, vol. 72 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 8 August 2016

Mayurkumar Ashwinbhai Makhesana and Kaushik M. Patel

The quality of the surface being machined and tool life are greatly affected by heat generated during machining. Abundant use of cutting fluid leads to higher production…

Abstract

Purpose

The quality of the surface being machined and tool life are greatly affected by heat generated during machining. Abundant use of cutting fluid leads to higher production rates and a threat for environment and worker’s health. Hence, the need is to identify eco-friendly lubricants. The purpose of the current work is to investigate the effects of solid lubricants (boric acid and molybdenum disulphide) mixed with oil during turning of EN-31 using cemented carbide tools. The concentration of solid lubricants in oil is varied to analyze output parameters such as surface roughness, process temperature, power consumption and tool wear.

Design/methodology/approach

EN 31 steel material is machined at various cutting speeds and constant feed and depth of cut to determine the effects of dry, wet and solid lubricant assisted machining.

Findings

Experimental study revealed that the solid lubricants performed better while machining and therefore it may be considered as environment friendly and cost effective way of lubrication as compared to flood cooling.

Research limitations/implications

The work can be extended to identify the effects of solid lubricants on micro hardness and cutting force.

Practical implications

From the findings of the work, solid lubricants may be considered as suitable choice as compared to fluid cooling because it improves process performance without much affecting the environment and worker’s health.

Originality/value

So far the use of solid lubricants in machining is limited. The results of the work will be useful to explore various efficient way to apply solid lubricants.

Details

Industrial Lubrication and Tribology, vol. 68 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 June 2000

T.E. Rajewski, J.S. Fokens and M.C. Watson

The use of lubricants in food production and processing is widely known. Over time, the regulations and requirements for lubricants in food machinery have evolved to…

Abstract

The use of lubricants in food production and processing is widely known. Over time, the regulations and requirements for lubricants in food machinery have evolved to include a wide variety of product technology. This technology includes many synthetic based formulated lubricants. This paper will focus on the types of lubricants available for use in the food industry, as well as the benefits and potential drawbacks of each lubricant type. It will also address the changing legislation surrounding the use of lubricants in food manufacturing and processing equipment.

Details

Industrial Lubrication and Tribology, vol. 52 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 26 September 2008

R. Martins, N. Cardoso and J. Seabra

This paper aims to investigate the scuffing load‐carrying capacity of three gear oils: a standard mineral lubricant containing extreme pressure and anti‐wear additives…

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Abstract

Purpose

This paper aims to investigate the scuffing load‐carrying capacity of three gear oils: a standard mineral lubricant containing extreme pressure and anti‐wear additives (M0) and two biodegradable saturated esters containing low toxicity additives (E1 and E2).

Design/methodology/approach

Four‐ball wear tests were performed, according to standard ASTM D4172. Results from the wear scar diameter and from ferrographic analysis of the test oil samples are presented and related to the lubricant properties. The physical, chemical and biodegradability properties of the lubricants are presented and compared.FZG gear scuffing tests were performed, according to standard DIN 51535, in order to evaluate the scuffing load‐carrying capacity of the two oils. Two reference tests were performed, A20/16.6/90 and A10/16.6/90.

Findings

Test results include scuffing load stage, maximum oil bath temperature, pinion weight loss and surface roughness measurement of the teeth flanks.

Originality/value

The paper provides information on the scuffing load‐carrying capacity of three gear oils.

Details

Industrial Lubrication and Tribology, vol. 60 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 9 August 2013

H.C. Garg and Vijay Kumar

This paper aims to investigate the effect of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal…

Abstract

Purpose

This paper aims to investigate the effect of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal bearing system operating with Newtonian and non‐Newtonian lubricants. The analysis considers the generalized Reynolds equation governing the flow of lubricant having variable viscosity in the clearance space and equation of flow of lubricant through constant flow valve restrictor. The non‐Newtonian lubricant is assumed to follow the power law. The performance characteristics are computed for the two values of power law index (n=1.0 and 0.566). The computed results indicate that the blockage of holes during operation will not be the likely causes for the imminent failure of a well‐designed non‐recessed hole‐entry hybrid journal bearing.

Design/methodology/approach

Finite element method has been used to solve generalized Reynolds equation governing the flow of lubricant having variable viscosity in the clearance space and equation of flow of lubricant through constant flow valve restrictor.

Findings

The computed results indicate that the blockage of holes during operation will not be the likely causes for the imminent failure of a well‐designed non‐recessed hole‐entry hybrid journal bearing. The bearing configuration with plugged holes provides sufficient fluid film thickness and low power requirement as less lubricant is required to be pumped in the bearing.

Originality/value

To the best of the author's knowledge, no study which considers the influence of plugging of holes on the static performance characteristics of a constant flow valve compensated hole‐entry hybrid journal bearing system operating with Newtonian and non‐Newtonian lubricant is yet available in the literature.

Details

Industrial Lubrication and Tribology, vol. 65 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 20 September 2021

Muhammad Bilal Khan, Rehan Zahid, Ali Hussain Kazim and Khalid Javed

Depleting reserves of crude oils and their adverse environmental effects have shifted focus toward environment friendly and biobased lubricant base oils. Natural oils and…

Abstract

Purpose

Depleting reserves of crude oils and their adverse environmental effects have shifted focus toward environment friendly and biobased lubricant base oils. Natural oils and fats act as good lubricants but they have low oxidation and thermal stability which makes them unsuitable for modern day uses. This paper aims to produce trimethylolpropane ester biolubricant from cottonseed oil and study the effects of its use in spark ignition (SI) engines.

Design/methodology/approach

In this work, cottonseed oil is converted to TMP lubricant by a two-step based catalyzed esterification. The lubricants thermophysical properties are then analyzed and a 20% blend with synthetic poly-alpha olefin is used in an spark ignition engine.

Findings

The produced lubricant has viscosity @100oC of 4.91 cSt, a viscosity index of 230 and a flash point of 202oC. When used as a 20% blend in a petrol engine, the rate of oil deterioration was reduced by 18%, however, the overall wear increased by 6.7%. However, this increase is offset by its improved environmental impacts.

Originality/value

In its current state, such a biolubricant can be used as an additive to most commercially available lubricants to improve oil deterioration characteristics and environmental impact. However, further work on improving biolubricant’s wear characteristics is needed for the complete replacement of mineral oil-based lubricants.

Details

Industrial Lubrication and Tribology, vol. 73 no. 7
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 16 August 2021

Bifeng Yin, Xuefeng Wang, Bo Xu, Gongyin Huang and Xin Kuang

The purpose of this paper was to improve the frictional wear resistance properties of piston skirts caused by the low viscosity lubricant by studying the tribological…

Abstract

Purpose

The purpose of this paper was to improve the frictional wear resistance properties of piston skirts caused by the low viscosity lubricant by studying the tribological performance of three novel coating materials.

Design/methodology/approach

Comparative tribological examinations were performed in a tribological tester using the ring-block arrangement under two viscosity lubricants, the loading force was applied as 100 N, the speed was set to 60 r/min and the testing time was 180 min.

Findings

Under low viscosity lubricant, the friction coefficient and wear of the three coatings all increase, and the friction coefficient and wear of the PTFE coating are the largest, while the MoS2 coating has the lowest friction coefficient and wear. Under low viscosity lubricant, the friction coefficient of the MoS2 coating is 2.1%–5.4% and 20.0%–24.3% lower than that of the SiO2 and PTFE coating, respectively. The friction coefficient and wear fluctuation rate of the MoS2 coating is the smallest when the lubricant viscosity decreases, which indicates that the MoS2 coating has excellent stability and adaptability under low viscosity lubricant.

Originality/value

To reduce the piston skirt wear caused by low viscosity lubricant in heavy-duty diesel engines, the friction and wear adaptability of three novel composite coating materials for piston skirts were compared under 0 W-20 low viscosity lubricant, which could provide a guidance for the application of wear-resistant materials for heavy-duty diesel engine piston skirt.

Details

Industrial Lubrication and Tribology, vol. 73 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

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