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1 – 10 of over 4000
Article
Publication date: 1 March 2006

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)…

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.

Details

Journal of Financial Management of Property and Construction, vol. 11 no. 1
Type: Research Article
ISSN: 1366-4387

Keywords

Article
Publication date: 3 February 2021

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…

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.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 17 December 2020

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…

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.

Details

Journal of Quality in Maintenance Engineering, vol. 27 no. 4
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 24 April 2020

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…

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 α 0.01, 0.02, 0.05, 0.1 and 0.2 levels of significance) illustrated that given the current data distribution pattern, there was a 3% likelihood that the ELV will be exceeded. Model parameters could be used to: forecast the future probability of HAV exposure levels on other utility contracts and provide benchmark indicators to alert senior management to pending breaches of the ELV.

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.

Details

Engineering, Construction and Architectural Management, vol. 27 no. 9
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 20 April 2015

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.

413

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.

Details

Engineering Computations, vol. 32 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 25 November 2020

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…

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

International Journal of Building Pathology and Adaptation, vol. 39 no. 5
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 3 August 2010

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

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.

Details

Journal of Financial Management of Property and Construction, vol. 15 no. 2
Type: Research Article
ISSN: 1366-4387

Keywords

Article
Publication date: 3 December 2018

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…

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.

Details

World Journal of Engineering, vol. 15 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 14 December 2020

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…

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

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 2 February 2021

Hao Wang, Guangming Dong and Jin Chen

The purpose of this paper is building the regression model related to tool wear, and the regression model is used to identify the state of tool wear.

Abstract

Purpose

The purpose of this paper is building the regression model related to tool wear, and the regression model is used to identify the state of tool wear.

Design/methodology/approach

In this paper, genetic programming (GP), which is originally used to solve the symbolic regression problem, is used to build the regression model related to tool wear with the strong regression ability. GP is improved in genetic operation and weighted matrix. The performance of GP is verified in the tool vibration, force and acoustic emission data provided by 2010 prognostics health management.

Findings

In result, the regression model discovered by GP can identify the state of tool wear. Compared to other regression algorithms, e.g. support vector regression and polynomial regression, the identification of GP is more precise.

Research limitations/implications

The regression models built in this paper can only make an assessment of the current wear state with current signals of tool. It cannot predict or estimate the tool wear after the current state. In addition, the generalization of model has some limitations. The performance of models is just proved in the signals from the same type of tools and under the same work condition, and different tools and different work conditions may have influences on the performance of models.

Originality/value

In this study, the discovered regression model can identify the state of tool wear precisely, and the identification performances of model applied in other tools are also excellent. It can provide a significant information about the health of tool, so the tools can be replaced or repaired in time, and the loss caused by tool damage can be avoided.

Details

Engineering Computations, vol. 38 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

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