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Article
Publication date: 13 March 2017

Chang-Guang Zhou, Yi Ou, Hu-Tian Feng and Zeng-Tao Chen

This paper aims to examine the precision loss of ball screw raceway under different operating conditions and geometry parameters.

Abstract

Purpose

This paper aims to examine the precision loss of ball screw raceway under different operating conditions and geometry parameters.

Design/methodology/approach

Based on a new coefficient K’ introduced especially for ball screws to reflect the actual contact condition, the modified Archard theory is applied to ball screws to obtain wear volume of the ball-screw contacts. Thus, the axial precision loss can be defined as the ratio of the wear volume to the contact area. Meanwhile, a novel running bench and a precision-measuring system of ball screws are conducted. Precision variation is obtained and analyzed during the whole life running test, which agrees well with the theoretical values calculated in this paper.

Findings

For a given rotational speed, the increasing rate of the precision loss rate is high at low axial load and then becomes small with the increasing axial load, whereas for a given axial load, the precision loss rate is proportional to the rotational speed. Besides, the precision loss rate is reduced with the increasing contact angle between a ball and the screw raceway, and is proportional to the helix angle when the angle changes from 1 to 10 degrees.

Research limitations/implications

The rotational speed used in this experiment is low and the ball screw is of no-load type, although results calculated by the model and Wei’s model seem close when the axial load is high, whether the model built in the paper is applicable to the condition of high rotational speed and preload still needs to be verified in the future work.

Practical implications

This study provides an accurate model to predict the precision loss of the screw raceway and estimate the remaining life of ball screws, which is significant for better performance of ball screws as well as the computer numerical control machine tools.

Originality/value

Previous studies on the wear of ball screws mainly focused on the drag torque analysis and mechanical efficiency estimation, and the experiment to verify their theoretical analysis was almost all limited to the test of drag torque or axial rigidity, which is neither sufficient nor persuasive. However, in this paper, the authors proposed a comprehensive wear prediction model which combines the modified Archard wear theory, Hertz contact theory and kinematic theory of ball screws. To the best of the authors’ knowledge, this kind of study has never been reported in the literature. In addition, for the lack of the test bench and high cost of the experiment, the whole life operation test, which is designed and conducted to confirm the model in this paper, has never been reported in literature either.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 6 February 2009

Rambabu Arji, D.K. Dwivedi and S.R. Gupta

The paper's aim is to investigate the sand slurry erosive wear behaviour of Ni‐Cr‐Si‐B coating deposited on mild steel by flame spraying process under different test conditions.

Abstract

Purpose

The paper's aim is to investigate the sand slurry erosive wear behaviour of Ni‐Cr‐Si‐B coating deposited on mild steel by flame spraying process under different test conditions.

Design/methodology/approach

Flame sprayed coatings of Ni‐Cr‐Si‐B were developed on mild steel substrate The slurry pot tester was used to evaluate wear behaviour of the coating and mild steel. The erosive wear test was conducted using 20 and 40 per cent silica sand slurry at three rotational speeds (600, 800 and 1,000 rpm).

Findings

Slurry erosive wear of the coating showed that in case of 20 per cent silica sand slurry weight loss increases with increase in rotational speed from 600 to 1,000 rpm while in case of 40 per cent silica sand slurry weight loss first increases with increase in rotational speed from 600 to 800 rpm followed by marginal decrease in weight loss with further increase in rotational speed from 800 to 1,000 rpm. Increase in wear resistance due to thermal spray coating of Ni base alloy on mild steel was quantified as wear ratio (weight loss of mild steel and that of coating under identical erosion test conditions). Wear ratio for Ni‐Cr‐Si‐B coating was found in range of 1.4‐2.8 under different test conditions. The microstructure and microhardness study of coating has been reported and attempts have been to discuss wear behaviour in light of microstructure and microhardness. Scanning electron microscope (SEM) study of wear surface showed that loss of material from the coating surface takes place by indentation, crater formation and lip formation and its fracture.

Practical implications

It would assist in estimating the erosion wear performance of flame sprayed Ni‐Cr coatings and their affects of wear resistance.

Originality/value

Erosion wear of flame sprayed coatings in sand slurry media medium is substantiated by extensive SEM study.

Details

Industrial Lubrication and Tribology, vol. 61 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 4 February 2014

Subhash Chandra Sharma and Doug Hargreaves

Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that…

Abstract

Purpose

Ideally, there is no wear in hydrodynamic lubrication regime. A small amount of wear occurs during start and stop of the machines and the amount of wear is so small that it is difficult to measure with accuracy. Various wear measuring techniques have been used where out-of-roundness was found to be the most reliable method of measuring small wear quantities in journal bearings. This technique was further developed to achieve higher accuracy in measuring small wear quantities. The method proved to be reliable as well as inexpensive. The paper aims to discuss these issues.

Design/methodology/approach

In an experimental study, the effect of antiwear additives was studied on journal bearings lubricated with oil containing solid contaminants. The test duration was too long and the wear quantities achieved were too small. To minimise the test duration, short tests of about 90 min duration were conducted and wear was measured recording changes in variety of parameters related to weight, geometry and wear debris. The out-of-roundness was found to be the most effective method. This method was further refined by enlarging the out-of-roundness traces on a photocopier. The method was proved to be reliable and inexpensive.

Findings

Study revealed that the most commonly used wear measurement techniques such as weight loss, roughness changes and change in particle count were not adequate for measuring small wear quantities in journal bearings. Out-of-roundness method with some refinements was found to be one of the most reliable methods for measuring small wear quantities in journal bearings working in hydrodynamic lubrication regime. By enlarging the out-of-roundness traces and determining the worn area of the bearing cross-section, weight loss in bearings was calculated, which was repeatable and reliable.

Research limitations/implications

This research is a basic in nature where a rudimentary solution has been developed for measuring small wear quantities in rotary devices such as journal bearings. The method requires enlarging traces on a photocopier and determining the shape of the worn area on an out-of-roundness trace on a transparency, which is a simple but a crude method. This may require an automated procedure to determine the weight loss from the out-of-roundness traces directly. This method can be very useful in reducing test duration and measuring wear quantities with higher precision in situations where wear quantities are very small.

Practical implications

This research provides a reliable method of measuring wear of circular geometry. The Talyrond equipment used for measuring the change in out-of-roundness due to wear of bearings indicates that this equipment has high potential to be used as a wear measuring device also. Measurement of weight loss from the traces is an enhanced capability of this equipment and this research may lead to the development of a modified version of Talyrond type of equipment for wear measurements in circular machine components.

Originality/value

Wear measurement in hydrodynamic bearings requires long duration tests to achieve adequate wear quantities. Out-of-roundness is one of the geometrical parameters that changes with progression of wear in a circular shape components. Thus, out-of-roundness is found to be an effective wear measuring parameter that relates to change in geometry. Method of increasing the sensitivity and enlargement of out-of-roundness traces is original work through which area of worn cross-section can be determined and weight loss can be derived for materials of known density with higher precision.

Details

Industrial Lubrication and Tribology, vol. 66 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 September 2015

Lin Ba, Zhenpeng He, Lingyan Guo, Young Chiang, Guichang Zhang and Xing Lu

The purpose of this paper is to improve the environment and save energy, friction reduction, lower oil consumption and emissions demand that are the chief objectives of…

Abstract

Purpose

The purpose of this paper is to improve the environment and save energy, friction reduction, lower oil consumption and emissions demand that are the chief objectives of the automotive industry. The piston system is the largest frictional loss source, which accounts for about 40 per cent of the total frictional loss in engine. In this paper, the reciprocating tribometer, which is updated, was used to evaluate the friction and wear performances.

Design/methodology/approach

An alternate method is introduced to investigate the effect of reciprocating speed, normal load, oil pump speed and ring sample and oil temperature on friction coefficient with the ring/liner of a typical inline diesel engine. The orthogonal experiment is designed to identify the factors that dominate wear behavior. To understand the correlations between friction coefficients and wear well, different friction coefficient results were compared and explained by oil film build-up and asperity contact theory, such as the friction coefficient over a long period and averaged the friction coefficient over one revolution.

Findings

The friction coefficient changes little but fluctuates with a small amplitude in the stable stage. The sudden change of frequency, load and stroke will lead to the oil film rupture. The identification for the factors that dominates the wear loss is ranged as F (ring sample) > , E (oil sample) > , B (stroke) > , D (temperature) > , A (load) > , G (liner) > and C (frequency).

Originality/value

This paper develops and verifies a methodology capable of mimicking the real engine behavior at boundary and mixed lubrication regimes which can minimize frictional losses, wear, reduce much work for the experiment and reduce the cost. The originality of the work is well qualified, as very few papers on a similar analysis have been published, such as: The friction coefficient values fluctuating in the whole stage may be caused by the vibration of the system; suddenly, boundary alternation may help the oil film to form the lubrication; and weight loss mainly comes from the contribution of the friction coefficient value fluctuation. The paper also found that the statistics can gain more information from less experiment time based on a design of experiment.

Details

Industrial Lubrication and Tribology, vol. 67 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 13 March 2017

Gaofeng Han, Pengfei Jiang, Jianzhang Wang and Fengyuan Yan

This report aims to study the influence of applied potentials on the corrosion-wear behavior of 316L stainless steel (SS) in artificial seawater.

Abstract

Purpose

This report aims to study the influence of applied potentials on the corrosion-wear behavior of 316L stainless steel (SS) in artificial seawater.

Design/methodology/approach

In this study, wear-corrosion behavior of 316L SS had been studied under different applied potentials in artificial seawater by using a reformed pin-on-disc test rig. The applied potentials were selected ranging from –1.2 to 0.3 V (vs Ag/AgCl). The friction coefficient, mass loss rate and current density were determined.

Findings

It was indicated that mass loss was determined by the combined effect of mechanical wear and chemical corrosion. The wear-corrosion process was synergistic effects dominate while mechanical wear contributed the major material mass loss.

Practical implications

The results helped us to choose the appropriate metals for application under the specified environment.

Originality/value

The main originality of this research is to reveal the corrosion-wear behavior of 316L SS under different potentials, which would help us to understand different states of 316L SS under different corrosion environments.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

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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 November 2006

Ilyas Uygur

To provide information about technical data; wear behaviour of worn rotor parts in mining industry and for the other application of ferrous alloys.

Abstract

Purpose

To provide information about technical data; wear behaviour of worn rotor parts in mining industry and for the other application of ferrous alloys.

Design/methodology/approach

Wear behaviour of the various filler wires were tested (tensile, hardness, and wear) and compared with each other in the light of microstructure, chemical, and mechanical properties.

Findings

The results showed that the wear rates were significantly increased with the increasing load, welding current, wear distance and poor mechanical properties. A larger amount of C, Cr, and Mn specimen showed the best wear resistance since it contained a number of hard MC‐type carbides and coarse grains. Furthermore, for all materials the weight loss increases linearly with the increasing of welding arc current, load and wear distance.

Research limitations/implications

It would be interesting to search about the toughness values and fatigue behaviour of these materials. It could be the good idea for future work could be concentrated fracture surface analysis of these materials.

Practical implications

For these materials choosing the right chemical composition of the filler material, certain arc current and ideal microstructure is crutial for the wear response.

Originality/value

The main value of this paper is to contribute and fulfil the mechanical properties of welding wires that is being studied so far in the literature such as the effects of chemical composition, applied road range, and arc current on the tensile, hardness and wear behaviours of the welding wires.

Details

Industrial Lubrication and Tribology, vol. 58 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 13 November 2017

Dawit Zenebe Segu and Pyung Hwang

This study aims to compare the friction and wear behaviors of Fe68.3C6.9Si2.5 B6.7P8.8Cr2.2Al2.1Mo2.5 bulk metallic glass (BMG) under sliding using dry, deionized…

Abstract

Purpose

This study aims to compare the friction and wear behaviors of Fe68.3C6.9Si2.5 B6.7P8.8Cr2.2Al2.1Mo2.5 bulk metallic glass (BMG) under sliding using dry, deionized water-lubricated and oil-lubricated conditions. The comparison was performed using a unidirectional ball-on-flat tribometer under different applied loads, and the results were compared to the properties of a conventional material, SUJ2. Fe-based BMG materials have recently been attracting a great deal of attention for prospective engineering applications.

Design/methodology/approach

As a part of the development of Fe-based BMGs that can be cost-effectively produced in large quantities, an Fe-based BMG Fe68.8C7.0Si3.5B5.0P9.6 Cr2.1Mo2.0Al2.0 with high glass forming ability was fabricated. In the present study, the friction and wear properties of Fe-based BMG has been comparatively evaluated under dry sliding, deionized water- and oil-lubricated conditions using a unidirectional ball-on-flat tribometer under different applied loads, and the results were compared to the properties of conventional material SUJ2.

Findings

The results show that the Fe-based BMG had better friction performance than the conventional material. Both the friction coefficient and wear mass loss increased with increasing load. The sliding wear mechanism of the BMG changed with the sliding conditions. Under dry sliding conditions, the wear scar of the Fe-based BMG was characterized by abrasive wear, plastic deformation, micro-cracks and peeling-off wear. Under water- and oil-lubricated conditions, the wear scar was mainly characterized by abrasive wear and micro-cutting.

Originality/value

In this investigation, the authors developed a new BMG alloy Fe68.8C7.0Si3.5B5.0P9.6Cr2.1Mo2.0Al2.0 to improve the friction and wear performance under dry sliding, deionized water- and oil- lubricated conditions.

Details

Industrial Lubrication and Tribology, vol. 69 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 4 September 2017

Dawei Yi, Zhiyun Zhang, Jin Chen, Libin Niu and Jianhong Peng

The directional solidification Fe-B alloy was prepared. The microstructures and three-body abrasive wear behaviors of directional solidification alloy were investigated.

Abstract

Purpose

The directional solidification Fe-B alloy was prepared. The microstructures and three-body abrasive wear behaviors of directional solidification alloy were investigated.

Design/methodology/approach

Fe-B alloy was melted in medium frequency induction furnace. The hardness was measured on HRS-150 Rockwell-hardness tester and HXD-1000TMC tester. The wear characteristic of the alloy was examined with a block-on-ring geometry. The worn surface of the alloy was investigated by scanning electron microscopy and laser scanning microscopy.

Findings

The wear weight loss and worn surface roughness increase with the increasing contact load in wear tests. When the worn surface is perpendicular to the boride growth direction, the highest hardness plane of the boride can resist abrasive effectively under the surrounding and supporting of the martensite matrix.

Originality/value

The relation between boride growth direction and wear direction will cause different boride breaking tendency and wear weight loss.

Details

Industrial Lubrication and Tribology, vol. 69 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 12 September 2016

Gülcan Toktaş and İmren Öztürk Yılmaz

The purpose of this study is to investigate the tribological properties of society of automotive engineers (SAE) 430B bronze-graphite composite, supplied in the form of…

Abstract

Purpose

The purpose of this study is to investigate the tribological properties of society of automotive engineers (SAE) 430B bronze-graphite composite, supplied in the form of machined and graphite embedded, used in sheet forming industry.

Design/methodology/approach

Pin-on-disc wear tests were performed under a constant normal load of 15 N and a sliding velocity of 60 mm/s. Due to the extended usage of Fe-based alloys in forming dies, pin materials were selected as cold work tool steel, gray and ductile irons. The weight losses of the disc (SAE 430B bronze-graphite composite) and the pins (Fe-based alloys) were measured separately under various sliding distances (5,000, 10,000 and 15,000 m). The average friction coefficients and wear tracks were obtained.

Findings

It is concluded that dry sliding behavior of SAE 430B bronze-graphite composite is the worst when operated with GGG-70 ductile iron due to its highest abrasive effect. The high hardness and nodular shape of graphite increased the abrasiveness of ductile iron. The improvement in wear resistance reached up to maximum 90 per cent and the degradation in friction coefficient was about 50 per cent by embedding graphite solids in bronze disc at dry sliding conditions.

Originality/value

Although the machined and graphite embedded bronze composites are indispensable parts of forming dies, there is no scientific knowledge on their dry sliding behavior.

Details

Industrial Lubrication and Tribology, vol. 68 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

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