Mechanical Engineering

CNC Wire cut electrical discharge machining (WEDM) has become an important non-traditional machining process which is used to manufacture intricate shapes with great accuracy and good surface roughness. Due to large number of process parameters and response characteristics, lots of researchers have attempted to model and optimize the process. This paper reviews the research trends in relation between different process parameters and different performance measures including Surface roughness (Ra),material removal rate (MRR), Dimensional deviation (DD), kerf width (KW) and wire wear ratio (WWR). In addition, this paper highlights different optimization methods and discusses their role in CNC WEDM process.

This present paper analyses the present status of edible oil manufacturing in the country. After basic study and OEE calculation, maintenance improvement program is implemented and gaps are identified. Mainly the degumming section are focused as it is one of the important section are identified. The main purpose of this present paper is to provide an overview of the typical processes and interrelations associated with a total integrated process and maintenance activities. OEE (Overall Equipment Effectiveness) are calculated regularly which will prove to be beneficial to those new in the industry. It must be stressed that this present research work attempts to touch in a limited number area of production equipments or departments. Continuous measurement of OEE has proven remarkable improvement.

Thermal designing of a shell and tube heat exchanger typically includes the determination of heat transfer area ,number of tubes, tube length and tube diameter ,tube layout, number of shell and tube passes ,tube pitch, number of baffles, its type and size, shell and tube side pressure drop. This paper reveals the effects various parameters in the thermal designing of shell and tube heat exchanger.

Scarcity of drinking water has been a major problem that most parts of this world are facing since years. Though many methods are there like electric water purifiers, they all are having very high initial and operational cost. Solar still is an exception for this. But, due to its lower yield, it is not yet commercialized. Most of those works to improve solar still efficiency and yield were given emphasize to improve the evaporation rate. But the condensation characteristics are also important. Condensing cover of the solar still and its inclination is one of such areas where detailed study is required. This research paper is intended to find the optimum inclination for the condensing cover for a solar still so as to get the maximum yield.

Biodiesel derived from nonedible feed stocks such as Mahua, Jatropha, Pongamia are detailed to be feasible choices for developing countries including India. This paper presents the results of investigation of performance and emissions characteristics of diesel engine using Mahua biodiesel. In this paper, the blends of varying proportions of Mahua biodiesel and diesel were prepared, analyzed and compared with the performance of diesel fuel, studied using a single cylinder diesel engine. The brake thermal efficiency, brake-specific fuel consumption, exhaust gas temperatures, Co, Hc, No, and smoke emissions was analyzed. The tests showed decrease in the brake thermal efficiencies (BTE) of the engine as the amount of Mahua biodiesel in the blend increased. The maximum percentage of reduction in BTE is 14.3% was observed for B-100 at full load. The exhaust gas temperature with the blends decreased as the proportion of Mahua increases in the blend. The smoke, Co, and No emissions of the engine were increased with the blends at all loads. However, Hc emissions of Mahua biodiesels were less than that of diesel.

Electric discharge machining (EDM) is a non-traditional machining processes that involved a transient spark discharges through the fluid due to the potential difference between the electrode and the work piece. In this experiment, EDM process on mild steel workpiece was conducted EDM Die Sinking Neu-ar. The electrodes used were copper, brass and graphite. This project is to be conducted using Taguchi method L4 orthogonal array. The parameters to be studied are peak current (12A and 21A), discharge ON time (10µs and 45 µs) and pumping direction (B0 and B1). This research aims to study the factors that influencing the machining of different electrodes in electrical discharge machining (EDM) process. Surface roughness was measured using surface roughness tester (SJ-301). Material removal rate (MRR) and electrode wear ratio were determined based on weighting the workpiece and electrode using digital weight scale. Then, the result of the experiment was analyzed by using EXCEL. The higher material removal rate in the EDM machine, the better is the machining performance while the lower electrodes wear ratio in the EDM machine is the better and accurate performance characteristic. The results show that copper electrode gives higher material removal rate which is 0.411 g/min than brass and graphite. Brass electrode gives better surface finishing which is 15 ?m and graphite electrodes give the better electrode wear rate which is 0.53 among two electrodes. Key words: Electrical Discharge Machining, Surface Roughness, Material Removal Rate, Electrode Wear Ratio.

This analysis investigated with the boundary layer flow and heat transfer aspects of a micropoloar nanofluid over a porous shrinking sheet with thermal radiation. The boundary layer equations governed by the partial differential equations are transformed in to a set of ordinary differential equations with the help of suitable local similarity transformations. The coupled nonlinear ordinary differential equations are solved by the implicit finite difference method along with the Thamous algorithm. Dual solutions of dimensionless velocity, angular velocity, temperature and concentration profiles are analyzed by the effect of various controlling flow parameters viz., Lewis number Le, thermophoresis Nt, Brownian motion parameter Nb, Radiation parameter R, Prandtl number Pr, material parameter K, mass suction parameter S, magnetic parameter M. Physical quantities such as skin frication coefficient, local heat, local mass fluxes are also computed and are shown in a table.

This study is to find out the best optimum ratio of the mixed waste materials of high-density polyethylene and wood’s flour by comparing the mechanical properties of recycled product (WPC). In this study, the fabrication process of wood plastic composite (WPC) contained of virgin material, post-consumer high-density polyethylene, and wood’s flour is through a twin-screw extruder and hot compression machine. The WPC product with four different ratio filler content based on weight percentage, i.e. 0 wt %, 20 wt %, 30 wt % and 40 wt % , were tested using universal tensile machine and impact tester according to ASTM D 3039, ASTM D 790, and ASTM D 6110 . The results of experiment showed that tensile and flexural properties of the composite increased with the adding of the wood’s flour material. The testing showed, however, totally opposite to the result of the impact test. In overall, the results of observations showed that recycled WPC have better mechanical properties compared to non-recycled WPC.

This paper presents the characterization of solid state sintering schedule for near-net shaping of warm formed metal powder compacts. Iron ASC 100.29 powder was used as main powder constituent during this investigation.  The feedstock was prepared by mechanically mixed iron powder with 0.4 wt% zinc stearate as admixed lubricant. The powder mass was then formed as solid cylinder at 180ºC.  The defect-free green compacts were sintered in an argon gas fired furnace at different sintering schedule. The sintered products were characterized through dimensional measurement, and mechanical testing. The results revealed that sintering schedule plays an important role in manufacturing near-net shape yet high strength components.

Gas carburizing is the most widely used surface hardening process for number of automobile and other heavy duty machinery components made up of ferrous material. Itis a complex process and many literatures shows that the defects are due to shape distortion and volume change. This work attempts to minimize the extent of those defects in gas carburized automobile parts through Taguchi’s DOE approach. The optimum combination of parameters which will alleviate the distortion problems are obtained through the response graph method. The results are compared with that obtained from S/N ratio method. The studies are validated through experiments. In addition the present study shows that the introduction of optimal conditions and elimination of straightening operation saves time and money.