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1 – 10 of over 4000Md.Tanvir Ahmed, Hridi Juberi, A.B.M. Mainul Bari, Muhommad Azizur Rahman, Aquib Rahman, Md. Ashfaqur Arefin, Ilias Vlachos and Niaz Quader
This study aims to investigate the effect of vibration on ceramic tools under dry cutting conditions and find the optimum cutting condition for the hardened steel machining…
Abstract
Purpose
This study aims to investigate the effect of vibration on ceramic tools under dry cutting conditions and find the optimum cutting condition for the hardened steel machining process in a computer numerical control (CNC) lathe machine.
Design/methodology/approach
In this research, an integrated fuzzy TOPSIS-based Taguchi L9 optimization model has been applied for the multi-objective optimization (MOO) of the hard-turning responses. Additionally, the effect of vibration on the ceramic tool wear was investigated using Analysis of Variance (ANOVA) and Fast Fourier Transform (FFT).
Findings
The optimum cutting conditions for the multi-objective responses were obtained at 98 m/min cutting speed, 0.1 mm/rev feed rate and 0.2 mm depth of cut. According to the ANOVA of the input cutting parameters with respect to response variables, feed rate has the most significant impact (53.79%) on the control of response variables. From the vibration analysis, the feed rate, with a contribution of 34.74%, was shown to be the most significant process parameter influencing excessive vibration and consequent tool wear.
Research limitations/implications
The MOO of response parameters at the optimum cutting parameter settings can significantly improve productivity in the dry turning of hardened steel and control over the input process parameters during machining.
Originality/value
Most studies on optimizing responses in dry hard-turning performed in CNC lathe machines are based on single-objective optimization. Additionally, the effect of vibration on the ceramic tool during MOO of hard-turning has not been studied yet.
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David J Edwards and Gary D Holt
The Control of Vibration at Work Regulations (CVWR), quantify workplace vibration exposure using exposure action, and exposure limit values (EAV and ELV respectively). Hand‐arm…
Abstract
The Control of Vibration at Work Regulations (CVWR), quantify workplace vibration exposure using exposure action, and exposure limit values (EAV and ELV respectively). Hand‐arm vibration (HAV) risk can be objectively assessed using hand‐tool vibration magnitude data, for comparison to the EAV and ELV. When considering risk controls, one disadvantage of this ‘focus’ on vibration magnitude, is that it might deflect appreciation of the economic implications of such controls, resulting from for example: restrictions on tool usage time; the need for operator rotas where continuous tool use is required; and complications in estimating labour costs because of these types of condition. Based on a sample of hand‐tools’ performance data, this research developed ‘hybrid’ (performance/vibration) dimensions for quantifying tools’ efficacy; representing (interalia) units of work achievable to reach the EAV and ELV. These hybrid dimensions characterize an alternative performance‐based (and therefore financially related) way of considering a tool’s ‘suitability’ within CVWR parameters; over and above the (selection) criterion of tool vibration magnitude. Analyses are then presented that investigate the time and cost ramifications of using multiple operators, to sustain continuous tool usage while keeping exposure levels within CVWR limits.
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S. Sarath and P. Sam Paul
A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly…
Abstract
Purpose
A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of the service period of the cutting tool while machining. It is significant to provide a corresponding real-time varying damping to control this chatter, which directly influences accuracy and quality of productivity. This paper aims to review the literature related to the application of smart fluid to control vibration in metal cutting and also focused on the challenges involved in the implementation of active control system during machining process.
Design/methodology/approach
Smart dampers, which are used as semi-active and active dampers in metal cutting, were reviewed and the research studies carried out in the field of the magnetorheological (MR) damper were concentrated. In smart materials, MR fluids possess some disadvantages because of their sedimentation of iron particles, leakage and slow response time. To overcome these drawbacks, new MR materials such as MR foam, MR elastomers, MR gels and MR plastomers have been recommended and suggested. This review intents to throw light into available literature which exclusively deals with controlling chatter in metal cutting with the help of MR damping methods.
Findings
Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. In the past, many researchers have attempted to implement MR damper in metal cutting to control vibration and were successful. Various methods with the help of MR fluid are illustrated.
Research limitations/implications
A new cutting tool is always well-defined and sharp at the onset of metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of service period of cutting tool while machining. Application of MR damper along with the working methodology in metal cutting is presented, challenges met are analyzed and a scope for development is reviewed.
Practical implications
This study provides corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity. Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration.
Social implications
This study attempts to implement smart damper in metal cutting to control vibrations.
Originality/value
It is significant to provide corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity.
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Adli B. Haddad and Bassem O.F. Al-Bedoor
In this paper, a vibration measuring technique that relies on the use of piezoelectric material and is originally developed to measure the vibration of turbine blade is adopted to…
Abstract
Purpose
In this paper, a vibration measuring technique that relies on the use of piezoelectric material and is originally developed to measure the vibration of turbine blade is adopted to measure the vibration of cutting tool in turning. The piezoelectric material is embedded at the root of the cutting tool. The scope of this research is to investigate the feasibility of using this technique by first conducting ANSYS simulation to solve the coupled field equations that govern the piezoelectric phenomenon followed by experimental work to compare the measured data with those obtained by conventional method to have an insight into the effectiveness of the adopted technique. Both simulation and experimental results show that the use of an embedded PZT sensor at the root of cutting tool is very useful for measuring vibration and can be used for further cutting operation control. In addition, it has captured more information than conventional vibration measurement techniques.
Design/methodology/approach
Vibration measurement of root-embedded PZT material to convert the dynamic cutting forces into vibration signals that can be used in cutting process optimization and improvement of cutting quality.
Findings
PZT material is found to be very responsive to high-frequency vibrations such that it can catch Chatter phenomena and can be used in developing control strategies.
Research limitations/implications
Mainly used for turning cutting process in this research. Other manufacturing process like milling special tool holder designs.
Practical implications
Can be used as online monitoring systems for cutting tool holders.
Social implications
Engineer and technician aid in quality assurance and control.
Originality/value
The new approach of embedding PZT material at the cutting tool root and the signals presentation and processing.
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Keywords
David John Edwards, Iain Rillie, Nicholas Chileshe, Joesph Lai, M. Reza Hosseini and Wellington Didibhuku Thwala
Excessive exposure to HAV can lead to hand–arm vibration syndrome (HAVS) which is a major health and well-being issue that can irreparably damage the neurological, vascular and…
Abstract
Purpose
Excessive exposure to HAV can lead to hand–arm vibration syndrome (HAVS) which is a major health and well-being issue that can irreparably damage the neurological, vascular and muscular skeletal system. This paper reports upon field research analysis of the hand–arm vibration (HAV) exposure levels of utility workers in the UK construction sector when operating hand-held vibrating power tools.
Design/methodology/approach
An empirical epistemological lens was adopted to analyse primary quantitative data on the management of hand-held tool trigger times (seconds) collected from field studies. To augment the analysis further, an interpretivist perspective was undertaken to qualitatively analyse interviews held with the participating company's senior management team after field study results. This approach sought to provide further depth and perspective on the emergent numerical findings.
Findings
The findings reveal that none of the operatives were exposed above the exposure limit value (ELV) and that 91.07% resided under the exposure action value (EAV). However, the Burr four parameter probability model (which satisfied the Anderson–Darling, Kolmogorov–Smirnov and chi-squared goodness of fit tests at
Originality/value
HAV field trials are rarely conducted within the UK utilities sector, and the research presented is the first to develop probability models to predict the likelihood of operatives exceeding the ELV based upon field data. Findings presented could go some way to preserving the health and well-being of workers by ensuing that adequate control measures implemented (e.g. procuring low vibrating tools) mitigate the risk posed.
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Istvan Keppler, Zoltan Hudoba, Istvan Oldal, Attila Csatar and Laszlo Fenyvesi
– The analysis of the effect of tool vibrations on the measured and simulated draught forces of cultivator tools. This paper aims to discuss this issue.
Abstract
Purpose
The analysis of the effect of tool vibrations on the measured and simulated draught forces of cultivator tools. This paper aims to discuss this issue.
Design/methodology/approach
Soil bin measurements and discrete element method (DEM)-based simulations.
Findings
The soil-tool interaction induced free vibrations of cultivator tools have significant impact on the measured draught force, and the simulations made by using vibrating tools give similar results.
Research limitations/implications
Accurate calibration of discrete element model parameters can be done based on the reproduction of the whole Mohr-Coulomb failure line. Draught force ratio – velocity ratio values seem to be independent of tool geometry and soil conditions in case of velocity ratio higher than 2.
Practical implications
DEM-based numerical simulations can be used for modeling the effect of tool vibration on the draught force values. During discrete element simulations of soil-tool interaction, the effect of tool vibration may not be neglected.
Originality/value
The paper demonstrates that during the discrete element modelling of the soil-tool interaction, the tool vibration phenomenon should not be neglected.
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David John Edwards, Igor Martek, Obuks Ejohwomu, Clinton Aigbavboa and M. Reza Hosseini
Human vibration exposure from hand-operated equipment emissions can lead to irreparable and debilitating hand-arm vibration syndrome (HAVS). While work-place health and well-being…
Abstract
Purpose
Human vibration exposure from hand-operated equipment emissions can lead to irreparable and debilitating hand-arm vibration syndrome (HAVS). While work-place health and well-being (H&WB) policies, strategies and procedures have been extensively researched and documented, little has been done to develop a specific strategic framework tailored to the management of hand-arm vibration (HAV). This study fills that gap.
Design/methodology/approach
A mixed philosophical approach of interpretivism and critical realism is adopted within a case study of a utilities contractor. Within this overarching epistemological design, action research approach is implemented via a three-stage investigation, namely, relevant company H&WB documents and procedures were examined, leading to the formulation of semi-structured interview questioning of the H&WB team. Their responses informed the next line of questions, delivered to middle-management responsible for overseeing H&S.
Findings
The findings are instructive in revealing that while substantial documentation management (augmented with protocols and checks) was in place, the system fell short of implementation within the workforce and thus failed to preserve worker H&WB. The investigation generated recommendations for shoring up H&WB deficiencies observed and developed a theoretical model to represent these. Though these recommendations were developed in response to a specific case, they form the core of a HAV operational H&WB strategy framework with applicability over a broader context.
Originality/value
This research provides unique insight into contemporary industry practices employed to manage HAV in the workplace and represents an invaluable opportunity to learn from prevailing practices and rectify deficiencies observed.
Details
Keywords
David J. Edwards and Gary D. Holt
As a tool to help compliance with relevant health and safety legislation, a cost‐effective method of risk assessing construction workers' exposure to hand‐arm vibration (HAV) is…
Abstract
Purpose
As a tool to help compliance with relevant health and safety legislation, a cost‐effective method of risk assessing construction workers' exposure to hand‐arm vibration (HAV) is presented that allows larger numbers of workers to be evaluated, either as a stratified sample of a population or as a population where numbers are not prohibitive.
Design/methodology/approach
The method, developed and tested in the field with a national UK contractor, employs work study to collect exposure level data of workers undertaking real work and analyse these, to inform HAV management and risk control decisions.
Findings
The method benefits from economies of scale to efficiently risk assess large numbers of workers, without the need for specialist equipment or analysis software. It can be applied to sample strata defined by, for example, equipment used, types of work or classifications of worker.
Research limitations/implications
Results add to the growing body of academic knowledge relating to construction worker HAV exposure and its management.
Practical implications
The method can easily be moulded to suit any type of construction organisation and help control cost associated with HAV legislation compliance.
Social implications
Potential benefits of controlled HAV exposure include reduced incidence of (HAV induced) medical conditions and concomitant personal financial gains to society.
Originality/value
The method and context are novel. The methodology of work study and sampling in a broader sense are well established.
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Priyabrata Sahoo, Mantra Prasad Satpathy, Vishnu Kumar Singh and Asish Bandyopadhyay
Surface roughness and vibration during machining are inevitable which critically affect the product quality characteristics. This paper aims to suggest the implementation of a…
Abstract
Purpose
Surface roughness and vibration during machining are inevitable which critically affect the product quality characteristics. This paper aims to suggest the implementation of a multi-objective optimization technique to obtain the favorable parametric conditions which lead to minimum tool vibration and surface roughness of 6063-T6 aluminum alloy in computer numerically controlled (CNC) turning.
Design/methodology/approach
The case study has been accomplished according to response surface methodology RSM’s Box–Behnken design (BBD) matrix using Titanium Nitride-coated Tungsten Carbide insert in a dry environment. As the experimental results are quite nonlinear, a second-order regression model has been developed for the responses (surface roughness and tool vibration) in terms of input cutting parameters (spindle speed, feed rate and depth of cut). The goodness of fit of the models has also been verified with analysis of variance (ANOVA) results.
Findings
The significance efficacy of input parameters on surface roughness and tool vibrations has been illustrated through multi-objective overlaid 3D surface plots and contour plots. Finally, parametric optimization has been performed to get the desired response values under the umbrella of weighted aggregate sum product assessment (WASPAS) method and verified confidently with confirmatory test results.
Originality/value
The results of this study reveals that hybrid RSM with WASPAS method can be readily applicable to optimize multi-response problems in the manufacturing field with higher confidence.
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Lawrance G., P. Sam Paul and Varadarajan A.S.
In the internal turning process, tool life and work piece quality are greatly influenced by the generation of heat in the cutting zone. During machining, cutting fluids are…
Abstract
Purpose
In the internal turning process, tool life and work piece quality are greatly influenced by the generation of heat in the cutting zone. During machining, cutting fluids are applied at the cutting zones to reduce heat generation and enhance tribological properties. However, in the boring process, cutting fluids cannot be applied at cutting zone properly, and wastage of cutting fluid is a threat to the ecology and personnel health. Hence, application of semisolid lubricant in the boring process is considered as an innovative technique for temperature reduction in cutting zone because of its eco-friendly system, which also has a higher ability of biodegradability. This paper aims to study the influence of semisolid lubricants comprising of grease,graphite, aluminium oxide in different composition applied at a tool–chip,tool–work interface using a semisolid lubricant applicator applied with varying pressure.
Design/methodology/approach
In the present study, the cutting performance during boring of AISI4340 steel is enhanced through the application of semisolid lubricant with different composition of grease, graphite and aluminium oxide applied at tool-work and tool-chip interface with varying pressure using semisolid lubricant applicator.
Findings
The results show that use of semisolid lubricant like grease, graphite and nano aluminium oxide at tool-chip interface with maximum pressure reduces cutting temperature, tool vibration, cutting force and surface roughness.
Originality/value
Reduce cutting temperature, tool vibration, cutting force and surface roughness.
Details