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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: 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: 21 September 2012

Sheri Kurgin, Jean M. Dasch, Daniel L. Simon, Gary C. Barber and Qian Zou

The purpose of this paper is to evaluate the cooling ability of minimum quantity lubrication (MQL) cutting fluid.

1139

Abstract

Purpose

The purpose of this paper is to evaluate the cooling ability of minimum quantity lubrication (MQL) cutting fluid.

Design/methodology/approach

An experimental system is devised to find the heat transfer coefficient of MQL under simulated reaming conditions. Cooling rate of the specimen is measured with an infrared camera. The effect of air pressure and oil volume on cooling rate is tested. Metal cutting tests are performed to evaluate the effect of heat transfer coefficient on workpiece temperature.

Findings

Convective heat transfer coefficient for MQL increases with increasing air pressure. Oil volume has an indeterminate effect on the heat transfer coefficient; however, it is a dominant factor for controlling temperature during reaming.

Practical implications

The results of the study can provide guidance to optimize the temperature controlling ability of MQL for production.

Originality/value

There is limited information available in literature regarding the heat transfer coefficient of metal working fluids, particularly for MQL. In particular, experiments designed to investigate the effect of air pressure and oil volume on the heat transfer coefficient of the mist have not been previously documented. This information may be used to improve the overall cooling ability of MQL mist, thus increasing its effectiveness at controlling tool wear and maintaining part quality. The other major contribution of this work is to separate the role of the cooling and lubrication for controlling temperature while reaming aluminum. Prior to this study, there has been relatively little research performed for the reaming metal cutting operation, and still less for reaming with MQL. The nature of how metal working fluids control temperature is not fully understood, and this work provides insight as to whether cooling or lubrication plays the dominant role for reaming.

Details

Industrial Lubrication and Tribology, vol. 64 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 12 July 2011

Sunday J. Ojolo, Olatunde Damisa and Oluwatoyin Iyekolo

The main purpose of this paper is to explore the use of solid lubricant during orthogonal machining of carbon steels. This is a pioneer work in Nigeria. Most works have…

296

Abstract

Purpose

The main purpose of this paper is to explore the use of solid lubricant during orthogonal machining of carbon steels. This is a pioneer work in Nigeria. Most works have been on oblique cutting using conventional oil as lubricants.

Design/methodology/approach

Different steels (low, medium and high carbon) were machined at different cutting conditions and tool geometries to determine the effects on surface characteristics while applying solid lubricant.

Findings

The results showed considerable improvement in the surface finish with the use of solid lubricant. There was also a decrease in surface roughness values as compared to wet machining.

Research limitations/implications

Further works on solid lubricant's effects on cutting force and residual stress could be done.

Practical implications

From the findings of this work, solid lubricant use can be advocated as a better alternative to conventional cutting fluid. It is easily recoverable from the chips after machining.

Originality/value

So far, in Nigeria, solid lubricant has not been exploited as coolant during machining. This paper will be a platform for other researches on solid lubricants as coolant during cutting/machining in Nigeria.

Details

Journal of Engineering, Design and Technology, vol. 9 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 13 April 2015

Diego Carou, Eva M. Rubio and J Paulo Davim

The purpose of this paper is to provide a practical review of the use of the minimum quantity lubrication (MQL) system in turning operations, focussing on the application…

Abstract

Purpose

The purpose of this paper is to provide a practical review of the use of the minimum quantity lubrication (MQL) system in turning operations, focussing on the application of the technique in the turning of different kind of materials.

Design/methodology/approach

The use of the MQL system was analysed by several researchers in the past years. Thus, in the present paper, a relevant sample of the main experimental studies that can be found in the literature was analysed to come up with a review with relevant information for researchers and industry.

Findings

The use of the MQL system can help to improve the outcomes of the turning process in several issues like surface quality or tool life. However, it was also recognised that in some cases, other cooling/lubricating methods can provide better results than the MQL system. Thus, the decision, whether to use or not the MQL system in a specific process, is of great importance.

Originality/value

The work is conveniently focussed to serve as a quick reference on the issue. At the same time, the work analysed the use of the turning of some of the main engineering materials that makes it useful for a wider range of researchers and metalworking firms. Finally, the review could be useful to improve the performance of the industry, especially for the metalworking firms in terms of costs, environmental impact and safety.

Details

Industrial Lubrication and Tribology, vol. 67 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 3 August 2015

Abas Abdoli, George S. Dulikravich, Chandrajit L Bajaj, David F Stowe and Salik M Jahania

Currently, human hearts destined for transplantation can be used for 4.5 hours which is often insufficient to test the heart, the purpose of this paper is to find a

Abstract

Purpose

Currently, human hearts destined for transplantation can be used for 4.5 hours which is often insufficient to test the heart, the purpose of this paper is to find a compatible recipient and transport the heart to larger distances. Cooling systems with simultaneous internal and external liquid cooling were numerically simulated as a method to extend the usable life of human hearts.

Design/methodology/approach

Coolant was pumped inside major veins and through the cardiac chambers and also between the heart and cooling container walls. In Case 1, two inlets and two outlets on the container walls steadily circulated the coolant. In the Case 2, an additional inlet was specified on the container wall thus creating a steady jet impinging one of the thickest parts of the heart. Laminar internal flow and turbulent external flow were used in both cases. Unsteady periodic inlet velocities at two frequencies were applied in Case 3 and Case 4 that had four inlets and four outlets on walls with turbulent flows used for internal and external circulations.

Findings

Computational results show that the proposed cooling systems are able to reduce the heart temperature from +37°C to almost uniform +5°C within 25 min of cooling, thus reducing its metabolic rate of decay by 95 percent. Calculated combined thermal and hydrodynamic stresses were below the allowable threshold. Unsteady flows did not make any noticeable difference in the speed of cooling and uniformity of temperature field.

Originality/value

This is the pioneering numerical study of conjugate convective cooling schemes capable of cooling organs much faster and more uniformly than currently practiced.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 25 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 2 May 2017

Hatem E. Gaffer, Mohamed R. Elgohary, Hassan Ali Etman and Saad Shaaban

The purpose of this paper was to synthesize novel antibacterial reactive dyes for dyeing cotton fabrics.

Abstract

Purpose

The purpose of this paper was to synthesize novel antibacterial reactive dyes for dyeing cotton fabrics.

Design/methodology/approach

Four synthetic novel antibacterial reactive dyes based on sulfonamide (D1-D4) have been synthesized by the coupling reaction of sulfonamide diazonium salt with sulfonamido-cyanurated 7-amino-4-hydroxynaphthalene-2-sulfonic acid “j-acid”. The chemical structure of the synthesized dyes was secured by their spectral data [infra red (IR) and proton Nuclear magnetic Resonance (1HNMR)].

Findings

The prepared reactive dyes (D1-D4) were applied to cotton fabrics. Optimum conditions of the dying samples at sodium sulfate 100 g/l, liquor ratio (L.R.) 1:10, sodium carbonate 20 g/l at 80°C (D1, D2 and D4), 60°C (D3 for 60 min) were investigated. The fastness properties toward washing, perspiration, rubbing and light were evaluated. Dyed fabrics showed good light fastness property and good to very good washing and perspiration fastness properties according to the gray scale. Antimicrobial activities for synthesized dyes showed excellent activity against gram-negative organisms such as Pseudomonas aeruginosa and Proteus mirabilis faecalis, whereas very good activity against gram-positive organisms such as Staphylococcus aureus and Enterococcus faecalis with respect to the standard drugs ampicillin and chloramphenicol.

Originality/value

The principle advantages in this study were that the synthesis of novel synthesized dyes by introducing bisulfonamide-based moieties to increase the antimicrobial activity of the cellulose fabrics could be used as a medical textile, short reaction time and reaction procedure conducted in few steps, the work up is convenient and thus the starting material can be easily prepared.

Details

Pigment & Resin Technology, vol. 46 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 2 August 2011

Anil Bilgihan, Fevzi Okumus, Khaldoon “Khal” Nusair and David Joon‐Wuk Kwun

This paper aims to propose a conceptual framework that illustrates how information technology (IT) applications may lead to competitive advantage in hotel companies.

11501

Abstract

Purpose

This paper aims to propose a conceptual framework that illustrates how information technology (IT) applications may lead to competitive advantage in hotel companies.

Design/methodology/approach

The paper is written based on a synthesis of previous literature in this area.

Findings

Multiple areas need to be carefully evaluated in developing and implementing IT projects so that they can lead to competitive advantage in hotel companies. There are four closely related areas when analyzing IT decisions in hotels, which include coherence between the business strategy and IT decision, types of IT applications, intended benefits of IT decisions, and decision‐making style. Technology sophistication, management skills, and integration of resources are key issues when implementing IT decisions. Investments into IT applications in hotel companies can lead to superior IT competencies and IT capabilities, which can subsequently result in lower cost, agility, innovation, added value for customers, and better customer service. However, not all IT investments may result in positive outcomes or their sustainability may be short lived. In addition, there can be a lag time between making IT investment decisions and seeing their intended outcomes.

Practical implications

There are multiple areas and issues that need to be considered in making and implementing IT investment decisions if they are to contribute to the company's competitive advantage. Hotel companies need to be selective in their IT investment decisions and look at each IT investment from the strategic management perspective.

Originality/value

This is one of the first articles in the hospitality field that offers a theoretical framework on how IT applications can lead to competitive advantage in hotels. It also offers numerous theoretical and practical implications. Therefore, this paper should help hotel executives and researchers in evaluating IT projects in hotel companies.

Details

Journal of Hospitality and Tourism Technology, vol. 2 no. 2
Type: Research Article
ISSN: 1757-9880

Keywords

Article
Publication date: 1 February 2016

Anil Bilgihan and Youcheng Wang

The purpose of this research is to assist hospitality organizations to better deploy and manage their information technology (IT) resources and enhance overall…

2559

Abstract

Purpose

The purpose of this research is to assist hospitality organizations to better deploy and manage their information technology (IT) resources and enhance overall effectiveness by demonstrating how technologies can be used as a competitive weapon at various levels from a managerial perspective. Both academia and practitioners attempt to understand the driving factors of IT-induced competitive advantage. While some firms enjoy competitive advantage through IT, others struggle to gain such competitive advantage.

Design/methodology/approach

AHLA E-Commerce and Technology Committee members were interviewed for their knowledge and insight toward the perceived problem. The committee comprises technology executives who meet twice per year to discuss the changing face of technology and e-business in the hospitality industry. Participants of this study consisted of vice presidents, CTO/CIOs of hotels, CEOs of hospitality technology vendors and academics who focus on hospitality technology research.

Findings

Findings indicate that IT-induced competitive advantage is possible when hotels choose to integrate all the possible technologies in the organization with a harmony that creates synergy. To create IT-induced competitive advantage, firms also need to allocate resources (human, knowledge and capital) effectively and invest in innovative and sophisticated technologies.

Research limitations/implications

IT can be used to create competitive advantage by means of differentiation, innovation, channel domination, cost reductions and efficiency improvements.

Practical implications

Four distinct stages of IT usage were identified. The first is the operation stage which includes technologies that are solely used to manage daily business operations. The second is the enhancement stage where IT applications are used to increase productivity and efficiency. IT applications at the strategic stage improves intra-organization and inter-organizational business processes. Finally, IT applications at the transformation stage enable companies to achieve the maximum competitive advantage.

Originality/value

The current research serves to fill the gap between academia and industry.

Details

Journal of Hospitality and Tourism Technology, vol. 7 no. 1
Type: Research Article
ISSN: 1757-9880

Keywords

Article
Publication date: 28 January 2021

Goh Chia Yee, Chin Jeng Feng, Mohd Azizi Bin Chik and Mohzani Mokhtar

This research proposes weighted grey relational analysis (WGRA) method to evaluate the performance of 325 multilevel dispatching rules in the wafer fabrication process.

Abstract

Purpose

This research proposes weighted grey relational analysis (WGRA) method to evaluate the performance of 325 multilevel dispatching rules in the wafer fabrication process.

Design/methodology/approach

The research methodology involves multilevel dispatching rule generation, simulations, WGRA and result analysis. A complete permutation of multilevel dispatching rules, including the partial orders, is generated from five basic rules. Performance measures include cycle time, move, tool idling and queue time. The simulation model and data are obtained from a wafer fab in Malaysia. Two seasons varying in customer orders and objective weights are defined. Finally, to benchmark performance and investigate the effect of varying values of coefficient, the models are compared against TOPSIS and VIKOR.

Findings

Results show that the seasons prefer different multilevel dispatching rules. In Normal season, the ideal first basic dispatching rule is critical ratio (CR) and CR followed by shortest processing time (SPT) is the best precedence pairing. In Peak season, the superiority of the rule no longer heavily relies on the first basic rule but rather depends on the combination of tiebreaker rules and on-time delivery (OTD) followed by CR is considered the best precedence pairing. Compared to VIKOR and TOPSIS, WGRA generates more stable rankings in this study. The performance of multicriteria decision-making (MCDM) methods is influenced by the data variability, as a higher variability produces a much consistent ranking.

Research limitations/implications

As research implications, the application illustrates the effectiveness and practicality of the WGRA model in analyzing multilevel dispatching rules, considering the complexity of the semiconductor wafer fabrication system. The methodology is useful for researchers wishing to integrate MCDM model into multilevel dispatching rules. The limitation of the research is that the results were obtained from a simulation model. Also, the rules, criteria and weights assigned in WGRA were decided by the management. Lastly, the distinguishing coefficient is fixed at 0.5 and the effect to the ranking requires further study.

Originality/value

The research is the first deployment WGRA in ranking multilevel dispatching rules. Multilevel dispatching rules are rarely studied in scheduling research although studies show that the tiebreakers affect the performances of the dispatching rules. The scheduling reflects the characteristics of wafer fabrication and general job shop, such as threshold and look-ahead policies.

Details

Grey Systems: Theory and Application, vol. 11 no. 4
Type: Research Article
ISSN: 2043-9377

Keywords

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