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The issue of cutting fluid is of great concern in present scenario of industry 4.0 due to its application in machining operation performed at wider parameter ranges. Despite of numerous advantages and enhanced machining performance, few critical issues like environmental and health hazards occurred if not controlled in efficient manner, consequently, set negative impacts on their utility. Hence, to safeguard aforementioned problems and to achieve environmental sustainability, the bio-degradable oils are gaining popularity due to their useful impact attained through latest lubrication techniques and amalgamation of nano and ionic fluids. Further, the cost of later fluids forms a barrier to their application in present competitive industrial framework as compared to conventional cutting fluids. In present investigation the survey was conducted on the scenario of cutting fluids application in small scale industries present in the Malwa belt of Punjab. The research was performed through well designed questionnaire consisting of various questions related to different aspects of cutting fluids such as fluid type, volume, application methods, recycling approach, disposal way and most important health as well as environmental issues. The data was collected by qualified engineers from various industries and further confirmed from the official source for its validity prior to analysis. The results of investigation confirmed that there was deficiency of advanced lubrication techniques utilization, insufficiency of post treatment and few cases of health hazards.

High-temperature corrosion of coal-fired boiler parts such as water walls and superheated tubes poses a serious threat to the efficiency of the thermal power plant. To overcome this, numbers of cor...

The present work deals with transient droplet evaporation and ignition process of an isolated n-heptane droplet at high pressure. The vapor–liquid equilibrium has been described by Peng–Robinson equation of state. In present numerical model, the effects due to elevated pressure, inert species mixing in the liquid phase and thermo-physical properties are considered as variable. The evaporation model has been comprehensively validated with experimental results available in the literature. For the present investigation, the ambient pressure has been varied from $$5$$ to $$80\;{\text{bar}}$$ and at constant ambient temperature of $$1000\;{\text{K}}$$ . The range of diameter was varied from $$0.5$$ to $$2.0\;{\text{mm}}$$ . The ignition delay was found to be strong functions of temperature, pressure and diameter. There is monotonic decrease in the ignition time due to increasing ambient temperature and pressure. At each pressure, there existed a minimum diameter below which ignition does not takes place and this minimum diameter decreases with increase in pressure.

This work presents a novel insight into slurry erosion behavior of thin layer of carbon fiber–epoxy-based composite adhered on 16Cr5Ni steel (adhesive coating) to evaluate its viability as a feasible candidate for slurry erosion applications. Experiments were conducted on a laboratory-developed slurry erosion test rig under accelerated conditions to study the effect erosion parameters namely slurry concentration, impact angle, and impact velocity. Under all the experimental conditions, adhesive coating showed better slurry erosion resistance in comparison with bare 16Cr5Ni steel specimens. Scanning electron microscopy analysis revealed that in the case of bare 16Cr5Ni steel; ploughing, micro-cutting, crater, plastic deformation, and lip formation were identified as main mechanism responsible for slurry erosion, whereas in the case of adhesive coating; pitting, cracking, fracturing, and shearing-off were found to be mainly responsible for material loss. It implies that adhesive coating showed a brittle mode of failure under slurry erosion conditions, whereas 16Cr5Ni steel exhibited a ductile mode of erosion.

Aluminum hybrid composites have the potential to satisfy emerging demands of lightweight materials with enhanced mechanical properties and lower manufacturing costs. There is an inclusion of reinforcing materials with variable concentrations for the preparation of hybrid metal matrix composites to attain customized properties. Hence, it is obligatory to investigate the impact of different machining conditions for the selection of optimum parameter settings for aluminum-based hybrid metal matrix composite material. The present study aims to identify the optimum machining parameters during wire electrical discharge machining of samples prepared with graphite, ferrous oxide, and silicon carbide. In the present research work, five different process parameters and three response parameters such as material removal rate, surface roughness, and spark Gap are considered for process optimization. Energy-dispersive spectroscopy and scanning electron microscopy analysis reported the manifestation of the recast layer. Analytical hierarchy process and genetic algorithm have been successfully implemented to identify the best machining conditions for hybrid composites.

Amid all convective heat transfer augmentation methods employing single phase, jet impingement heat transfer delivers significantly higher coefficient of local heat transfer. The arrangement leading to nine jets in square array has been used to cool a plate maintained at constant heat flux. Numerical study has been carried out using RANS-based turbulence modeling in commercial CFD Fluent software. The turbulent models used for the study are three different “k-ε” models (STD, RNG, and realizable) and SST “k-ω” model. The numerical simulation output is equated with the experimental results to find out the most accurate turbulence model. The impact of variation of Reynolds number, inter-jet spacing, and separation distance has been considered for the geometry considered. These parameters affect the coefficient of heat transfer, temperature, and turbulent kinetic energy related to flow. The local “h” values have been noticed to decline with the rise in separation distance “H/D.” The SST “k-ω” model has been noticed to be in maximum agreement with the experimental results. The average value of heat transfer coefficient “h” reduces from 210 to 193 W/m2K with increase in “H/D” from 6 to 10 at “Re” = 9000 and S/D of 3. As per numerical results, inter-jet spacing “S/D” of 3 has been determined to be the most optimum value.

In the present study, the influence of interlayer is evaluated on friction stir welding of AA6082 aluminium alloy. Zn and Cu alloying elements in proportion mixed with adhesive are used as an interlayer. Interlayer is preplaced in a gap of 0.2 mm between the abutting plates. Friction stir welding is carried out at various rotational and welding speeds. Thereafter joints are evaluated for tensile properties. It is found that FSW joints prepared with interlayer possess higher tensile strength than joints produced without interlayer.

Objectives: To develop a methodology for cell formation (i.e. recognition of part families and corresponding operation groups) for a Reconfigurable Manufacturing System (RMS) using a block diagonalized matrix. Method: Like Cellular Manufacturing System (CMS), the foundation of RMS lies on the premise of group technology. The present work highlights the peculiarities of RMS Vis a Vis CMS. CMS cell formation problem has a vast literature available. The present work intends to evolve a methodology for RMS cell formation relies on adapting suitably a CMS cell formation methodology with RMS peculiarities in focus. The method consists of two steps, first the matrix representing part-operation data is diagonalized and then the adapted cell formation methodology is applied on this diagonalized matrix to form the RMS cells. Findings: The effectiveness of the proposed methodology has been compared with some standard problems from the CMS literature and reported to work satisfactorily. Novelty/Improvement: The present work provides an initial framework for the RMS design which is a promising Manufacturing System paradigm for future. General Terms: Cell Formation, Reconfigurable Manufacturing Systems.

Plasma spray technique is utilized to cover the Induced Draft (ID) fans with 88%WC–12%Co (wt%) powder and 87%Al2O3–13%TiO2 (wt%) powder. The material of ID fan was ASTM A36 steel (IS2062) grade. The main focus of recent study was to investigate the influence of nature and characteristics (mainly hardness, coating thickness, bond strength, and porosity). Two coating powders with dissimilar particle size and their distribution, shape, and density were sprayed by similar parameters of plasma spraying conditions. The morphology of both the coatings was investigated by Scanning Electron Microscopy, which exhibits the sub-micro and micro-sized structure, with same thickness and porosity. Very intense and consistent was obtained and the variation in precursor size does not affect the coating structure.

The transient modeling of radiation effects on combustion of an isolated nonane and hexanol droplet in standard atmospheric conditions with finite rate chemistry has been performed. Transient effects have been included in a comprehensive manner by including initial droplet heating, variable liquid and gas phase properties and non-luminous gas radiations. Results show that gas radiations are important for determining various parameters in droplet combustion. Estimation of Planck's mean absorption coefficient is critical for non-luminous gas radiation modeling. Gas radiation suppresses gas, liquid and flame temperatures. The burning rate decreases in the presence of radiative losses with increasing initial droplet diameter.

Electric Discharge Machining (EDM) is one of the most commonly used non-traditional machining processes. Complex geometries can be easily manufactured using EDM. Material removal is achieved by producing continuous spark occurring between well shaped tool electrode and work piece. EDM does not involve direct contact of tool and work piece. Machining process involves a number of input variables like, current, voltage, pulse on/off which in turn affect the machining efficiency of EDM. These process parameters must be optimized to attain high material removal rate and low tool wear rate. The present paper presents theoptimization of tool wear rate of copper and brass electrode on machining of EN-47 using Response Surface Methodology (RSM).

Welding is basic part of the most modern assembly and manufacturing operations. Shielded metal Arc Welding process has hard facing and fabrication job application due to low cost electrode, increasing alloy transfer efficiency and low dilution with substrate without losing production capacity. SMAW electrode is coated with metal mixture called flux, which on decompose produce gases to restrict weld contamination, generating deoxidizers to disinfect the weld. The choice of electrode for SMAW lies on a number of factors, like weld material, welding direction and the preferred weld properties. The present paper investigate the microstructure and hardness properties of the Low carbon steel pipe welded using shielded metal arc welding with different electrode combinations.

The paper present the effect of current flow and Deep Cryogenic Treatment (DCT) on the Surface Roughness (SR) of AISI D3 steel machined using EDM. The EDM tool is modified using deep cryogenic treatment to obtain positive results. Cryogenic treatment is a add on process over conventional heat treatment processes which converts retained austenite to martensite along with formation of nano sized carbide. The treatment enhance the properties of materials like wear resistance, hardness, dimensional stability, thermal conductivity and tool consumption rate which are recognized as a important factors in industries. The results show that increase in current level enhance the surface roughness, while deep cryogenic treated electrodes produces less surface roughness as compared to that of non-cryogenic treated electrodes.

Electric discharge machining is recognized as most popular non conventional machining process. It is known for its ability to cut hard materials that are difficult to machined by conventional machining process. In EDM material is removed from work piece by continues occurring electric spark between the work piece and electrode. The major difficulty encountered in EDM is of high tool wear rate and low material removal rate. The present study investigate the effect of deep cryogenic treatment on tool wear rate and material removal rate at different current level setting with EN-31 as work piece material and Copper, Brass and Graphite as electrodes with and without deep cryogenic treatment. There is significant improvement in material removal rate and reduction in tool wear rate with cryogenic treatment.

Reconfigurable Manufacturing System (RMS) has been envisaged to fulfil the dynamic requirements of present manufacturing environment by adjusting its capacity and functionality. The proposed methodology is consisting of three stages. In the first stage, the clustering of Part Operation Incidence Matrix (POIM) is done by using a standard clustering technique. In the second stage, one operation sequence is selected for each part type. Finally, the reduced POIM corresponding to operation sequences selected in the last stage is used for simultaneous formulation of part families and operation groups. The proposed methodology has vast potential for experimentation with other CMS clustering methods.

Erosion is a major problem for the power generation plants for any country. A very high cost induced per annum accounting for the downtime of replacement/repair of boiler components of coal fired power plants due to oxidation and erosion.Thermal spray coating technique is a method used for coating the mechanical components in order to enhance the surface properties of the base material like resistance to corrosion, wearand erosion. In the present study, the cermet powders and coatings (wt% age) are applied on steel substrate with the help of plasma spray gun technique. Techniques like XRD, SEM/EDX and EPMA analysis have been used for characterization of the coatings. These coated materials were subjected to a Pin-on-Disc wear testing.The coated samples have shown almost negligible wear loss as compared to the uncoated samples. Further sliding wear resistance of is almost double of that of coated samples.

In present study, transient state one-dimensional heat conduction is analyzed using polynomial approximation method. In comparison with the classical lumped model, an improved lumped model have been employed as the classical lumped model is applicable for biot number of less than 0.1 and it cannot be used for high temperature gradient. An improved lumped model has been employed for sphere to calculate average temperature as a function of time for higher and lower values of biot number. The study shows that the lumped model provides better accuracy as compared to finite difference model.

Tuberculosis is a communicable disease which at time is difficult to diagnose. Many rapid tests have been developed based on different principles to detect antibodies or antigen in the sample. These rapid tests have shown varying degrees of sensitivity and specificity. In general, immunodiagnostic tests detecting antibodies can provide indirect evidence of current and past infections in organism of interest. With the exception of the tuberculin skin test (TST), immunodiagnostic tests have not been widely used for chronic TB infections because of the low sensitivity and specificity. Many antigens such as lipoara-binomman, cord factor, A60, 38 kDa, and 16 kDa have been used for antibody detection kits. The results for such immunodiagnostic tests varied markedly with sensitivity ranging from 15.7% to 89.2% and specificity from 50% to 100%. Demonstration of intact Mycobacterium tuberculosis or its breakdown products in the body fluid is a definite indication of the presence of the pathogen and has been the basis of antigen-based assay. Using a variety of methods, for example, RIA, EIA, haemagglutination, and latex agglutination, antigen has been demonstrated in sputum, CSF, pleural fluid, and ascetic fluid from the patients having tuberculosis.1, 2 Kadival et al (1982) standardised RIA using immunoreactive fraction of sonicate antigens of H37 RV obtained by sephrose 6B chromatography. The sensitivity of the assay was 1 × 103 organism/mL. Target antigens vary markedly depending on the nature of the clinical samples and test format. ELISA techniques like sandwich ELISA (sELISA) and dot-ELISA have been used for the antigen detection. Lipoarabinomannan (LAM) has been most frequently used as the target antigen, and its monoclonal and polyclonal antibodies have been used to detect antigen in sputum samples.3 The problem with using LAM as target antigen is the nonspecificity due to the presence of antigen in other mycobacterial species. Other antigens such as whole cells, culture filtrate protein (CFP), PPD, 65 kDa, and 14 kDa have been used. The sensitivity varied from 50% to 90% and specificity from 80% to 100%.4 Culture confirmation using LJ medium has the inherent disadvantage of the time required to observe the growth. This on many occasions can delay the start of treatment and may even allow the disease to cause more damage and even spread to other organs. Detection of TB antigen using specific antigen detection kit can provide a direct evidence of the infection and help in early start of the treatment. The limitation of antigen detection is the low sensitivity due to the scarcity of the TB antigen in clinical samples such as CSF, pleural fluid, blood, and urine. We evaluated a commercially available TB antigen detection kit manufactured by BioMed Industries, J Mitra, Parwanoo, Himachal Pradesh, India. Three different categories of samples (BAL, pleural fluid and sputum) were screened for TB antigen, and the results were compared with TB PCR. Some known AFB-positive sputum samples were also screened by the TB antigen detection kit as positive control. The samples were collected from Respiratory Disease OPD and patients admitted in Army Hospital, Delhi Cantonment. A total of 2272 samples were processed for TB PCR during the period from March 2007 to November 2008; 401 (17.64%) samples were found positive by PCR. Of the 401 PCR-positive samples, 38 (9.47%) were found positive by rapid kit. The PCR-positive sputum samples gave maximum positivity (13.28%). TB antigen was negative in 363 of 401 (90.52%) cases; 122 known AFB-positive sputum samples were also screened by the rapid kit and only 47 (38.52) were found positive. TB PCR has sensitivity and specificities in the range of 60% to 100%.5 Overall TB PCR percentage positivity in our samples was low (17.64%). Further, samples that had bacterial load (+++ and ++++) showed 100% positivity while for lower bacterial load (+ to ++) it was only 12.06% and 42.85%, respectively. Overall positivity was 38.52%. The smear sensitivity is usually influenced by a variety of factors including types of specimen and species of infecting mycobacterium.6 Thus, sensitivity of the rapid kit (13.28%) is even below the AFB smear examination. TB antigen in sputum detection using ELISA-based techniques (sELISA and dot-ELISA) had better sensitivity and specificity that varied from 71% to 91%. The detection of TB antigen using sELISA in CSF has shown sensitivity as high as 90% positivity,7 24 kDa and 19 kDa antigen are being found positive by immunoblotting in sera of many sputum-negative patients. In one recent study the detection of antigen like lipoarabinomannan in urine has not shown encouraging results.8 The data from our study shows that rapid test kit used for antigen detection does not possess higher sensitivity and specificity than AFB smear examination and PCR. Further refinement and development of more sensitive and specific rapid antigen detection kits in future remains a possibility.