WHILE machining, a cutting tool undergoes changes in geometrical shape and so‐called concentrated wear takes place in addition to normal wear on the clearance face. This type of…
Abstract
WHILE machining, a cutting tool undergoes changes in geometrical shape and so‐called concentrated wear takes place in addition to normal wear on the clearance face. This type of wear is mainly due to thermo‐electric current generated in Machine‐Tool‐Workpiece‐Machine (MTWM) circuit, the whole system being on two different temperature gradients. This type of wear may be of little significance in the case of a rough machining operation but is of great importance in very fine machining operations since it effects surface roughness and dimensional accuracy of the job.
These authors reported work on cutting oils in our September/October 1972 issue and this paper describes a continuation of their work. The selection of special cutting fluids and…
Abstract
These authors reported work on cutting oils in our September/October 1972 issue and this paper describes a continuation of their work. The selection of special cutting fluids and lubricants can significantly affect metal cutting operations. Friction forces during metal cutting can increase the amount of work to be done to deform the material, can increase tool wear, and can increase surface roughness of the workpiece. The frictional force can be reduced by the correct selection of cutting oil. In this paper the authors describe work to investigate the performance of molybdenum disulphide and graphite‐based cutting fluids and lubricants when machining mild steel under different processes. The results suggest that graphite‐based fluids give the better results under these experimental conditions.
Sagnik Bagchi and Surajit Bhattacharyya
This paper aims to explore whether India’s export basket in the bilateral intra-industry trade (IIT) with two of its top trading partners characterize robust export earnings or…
Abstract
Purpose
This paper aims to explore whether India’s export basket in the bilateral intra-industry trade (IIT) with two of its top trading partners characterize robust export earnings or not. This is pertinent for two reasons. First, India has a persistent problem of current account deficit for over decades now. Second, whether India’s export diversification strategy by participating in global value chains to improve export share in the world market led to the problem of the fallacy of composition.
Design/methodology/approach
This study considers bilateral trade data between India-USA and India-China at the HS-6 digit level over the period 1990–2018. The magnitude of total IIT is computed using the Grubel and Lloyd (1971) index. This paper then uses the unit value dispersion criterion to disentangle the magnitude of total IIT into horizontal and vertical IIT. Through a stepwise econometric exercise, this paper explores the attributes of exported goods in the IIT basket in terms of the directions of ToT, export share and export-price elasticity.
Findings
Across the two country pairs, the major contributors to the upsurge in IIT are five manufacturing industry groups of chemical, plastics and rubber, textiles, base metals and machinery and mechanical appliances. Across the industry groups, the dominant form of IIT has been low vertical IIT. Most of the industry groups do not characterize robust export earnings as the commodity groups have an elastic demand and an increasing trend of Terms of Trade (ToT). The exceptions are the industry groups of chemicals and textiles in India-China and India-USA, respectively.
Research limitations/implications
The concern of slim export earnings in most industry groups offers scepticism in maintaining the sustainability of the current account. The problem of the fallacy of composition also cannot be ruled out given the dominance of low vertical IIT. This study argues that these industry groups need to engage in labour market reforms and require access to easy credit to achieve competitiveness in the world market.
Originality/value
The analysis performed in this paper attempts to integrate the Prebisch-Singer hypothesis in the context of IIT. Empirical evidence to such an issue is not profound.
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H. Bagchi, N.P. Mukherjee, S.K. Basu and C.G. TRESIDDER
The significant cutting parameters in turning EN 24 steel with carbide tools using MoS2 as a cutting fluid have been evaluated and an equation connecting the significant…
Abstract
The significant cutting parameters in turning EN 24 steel with carbide tools using MoS2 as a cutting fluid have been evaluated and an equation connecting the significant parameters with surface roughness of the job material has been determined. A typical nomogram has been constructed to determine easily the surface roughness produced on the job when the independent variables are known within the range of experimentation. A comparative study between ordinary cutting fluid and MoS2 as a cutting fluid has been shown. Optimum cutting combinations have been ascertained statistically by the steepest descent method.
Kiran G. Sirsath and Bhanudas D. Bachchhav
Low performance life and increased machine downtime due to wear of resistance welding copper electrode is of major concern in fin–tube resistance welding in waste heat recovery…
Abstract
Purpose
Low performance life and increased machine downtime due to wear of resistance welding copper electrode is of major concern in fin–tube resistance welding in waste heat recovery boilers. The purpose of this study is to investigate an alternative material with good wear resistance to replace the currently utilized C11000 electrolytic tough pitch (ETP) copper electrode.
Design/methodology/approach
In this study, a Cu-Cr-Zr ternary alloy was developed for fin-to-tube welding electrode by melting commercial grade electrolytic copper (99.9% purity) plates, chips of chromium, powder of zirconium at 1100°–1300°C, followed by hot forging and precipitation hardening at 450°–550°C to attain appropriate grain flow. Microstructures of Cu-Cr-Zr alloys were analysed using scanning electron microscopy coupled with energy-dispersive backscatter electron spectrometry.
Findings
Wear performance of Cu-Cr-Zr and C11000 ETP Cu was evaluated using pin-on-disc set-up with Taguchi’s L8 orthogonal array. Ranking of the parameters was done, and it was observed that the material and temperature play a very significant role in controlling the wear of an electrode.
Practical implications
Rate of fin–tube resistance welding was increased by 26% with Cu-Cr-Zr alloy. Further investigation on effect of plasma on the metallurgical characteristics of Cu-Cr-Zr is recommended.
Originality/value
Tribo-mechanical performance of newly developed Cu-Cr-Zr ternary alloy was compared with C11000 ETP copper.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2023-0092/
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Bhanudas Dattatraya Bachchhav and Pramod Shivaji Kathamore
Formulation of mineral-based specialty lubricants without anti-wear (AW) and extreme-pressure (EP) additives is a challenging task. This study aims to propose an environment…
Abstract
Purpose
Formulation of mineral-based specialty lubricants without anti-wear (AW) and extreme-pressure (EP) additives is a challenging task. This study aims to propose an environment friendly alternative to mineral-based lubricants with superior wear preventive characteristics.
Design/methodology/approach
In this study, analysis of wear under trimethylolpropane trioleate (TMPTO)-based lube using operating parameters of four-ball tester was done. The effects of type of lube oil, temperature, load and speed on specific wear rate were investigated using Taguchi L27 orthogonal array. Based on the Taguchi experimental results and single-to-noise ratios, ranking of the four ball parameters was done. The surface analysis of worn steel balls was carried out using optical microscopic images of wear scar and energy dispersive spectrometry (EDS).
Findings
Results depict that the blend of sulfurized additives with TMPTO base oil showed a synergistic effect in terms of reduction in specific wear rate by the formation of protective film layer on the surface. The possible physical or chemical interactions between base oil and additives were studied based on the surface morphology of test balls.
Practical implications
The formulated lubricant has the potential to be used as a tapping/broaching oil.
Originality/value
To the best of the authors’ knowledge, the paper is a novel study investigating the effect of different additive in TMPTO. The results could prove beneficial in making TMPTO-based lube oil a viable replacement of mineral-based oils.
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Pramod S. Kathamore and Bhanudas D. Bachchhav
The screening of lube oil performance prior to field trials is the most significant for the formulation of novel lubricants. This paper aims to investigate the efficacy of…
Abstract
Purpose
The screening of lube oil performance prior to field trials is the most significant for the formulation of novel lubricants. This paper aims to investigate the efficacy of trimethylolpropane trioleate oil (TMPTO) based lubricants with different additives.
Design/methodology/approach
In this endeavor, initially five lubricating blends along-with TMPTO based oil with variable additives were evaluated for their tribological performances using ASTM standards. Out of these, the top three best-performing oils were further investigated for possible physical or chemical synergies among lube oils, additives and ball surface using SEM. The molecule structures of TMPTO based lube oils were confirmed using Fourier transform infrared spectroscopy (FTIR).
Findings
The wear preventive and extreme pressure characteristics of different TMPTO based samples were evaluated and compared for compatibility and synergy of additives. Morphological analysis of SEM images was used to understand the wear behavior of the worn surfaces.
Practical implications
Further investigation of TMPTO oil on its oxidation stability at high temperature and pressure to make it technologically competitive and commercially viable metal-working lubricant is suggested.
Originality/value
This paper highlights the tribo-effects of TMPTO to be rendered as a suitable lubricant for metal-cutting operations. The surface morphology of the worn-out surface significantly demonstrates the effect of loading conditions.
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Maria Manuela Natário, João Pedro Almeida Couto and Carlos Fernandes Roque de Almeida
The purpose of this paper is to analyze the dynamics of the triple helix model in less favoured regions, examining the role of three spheres: universities, firms, and government…
Abstract
Purpose
The purpose of this paper is to analyze the dynamics of the triple helix model in less favoured regions, examining the role of three spheres: universities, firms, and government. The paper identifies profiles of behavior in terms of triple helix model performance from the firm's perspective and recognizes key factors for successful innovation dynamics in a less favored region of Portugal.
Design/methodology/approach
A brief bibliographic revision regarding development of the triple helix model in the innovation process is followed by a description of the role of the helixes and the presentation of a model, after which the hypotheses are defined for testing. The methodology consists of a survey involving companies in a less favored region of Portugal and the application of multivariate statistical analysis “k‐means clusters” to detect behavioral patterns in terms of performance and dynamics of the triple helix model from the firm's viewpoint. In order to verify the hypotheses, tests of multiple average differences are used to assess the unique characteristics of each cluster and the independent test of Chi‐square.
Findings
The results point to the existence of a positive relationship between the dynamics of the triple helix model in terms of different types and objectives to innovate, namely, in regards to introducing new products as well as ecological innovation and their efforts to improve communications relative to the obstacles to innovate – explicitly, the lack of information and geographical location, the companies' innovation performance, and the level of cooperation and interaction with the university producing benefits for them in obtaining additional financial resources and prestige for the researcher, as well as by obtaining information for the education process.
Originality/value
The paper contributes to a greater theoretical understanding of the variables influencing implementation of the triple helix model in less favoured regions. It reveals conditions associated with a more active and proactive stance and consequently better innovation dynamics and regional attractiveness.
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Abstract
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Bhanudas Dattatraya Bachchhav, Geeta S. Lathkar and Harijan Bagchi
This paper aims to present a study of frictional characteristics of steel/die steel pair under sliding contact in presence of a set of formulated lubricants. AISI 1010 low carbon…
Abstract
Purpose
This paper aims to present a study of frictional characteristics of steel/die steel pair under sliding contact in presence of a set of formulated lubricants. AISI 1010 low carbon steels, although being strong, are less formable grades of steel and require appropriate selection of lubricants in tribological conditions.
Design/methodology/approach
A total of three mineral-based lubricating blends were formulated for varying concentration of ester. Plan of experiments, based on Taguchi’s analysis technique were performed using dedicated test rig based on “pin-on-disc” principle.
Findings
A correlation was established between additive concentration, sliding speed and pressure with coefficient of friction by multiple linear regression. On the basis of experimental results and S/N ratio analysis, ranking of the parameters has been done. A possible regime of working with such lubricants is also suggested.
Practical implications
Due to voluminous data involved, a few dominant process parameters were taken into consideration for the study.
Originality/value
This paper is highlighting the tribo-effects of additives to render it as suitable lubricant in sliding contact conditions. This paper also suggested an approach for selection of optimum regime of working in the light of “Stribeck Curve” for ester-containing lubricating oils.