Die-Sink Electric Discharge Machining (DS-EDM) is a preferred advanced method, used to produce the complex geometry, cavities, die, and mold facing difficult in cutting the materials. In the current research work, machining of AISI420 stainless steel with copper electrode has been performed. Gap voltage (V), Pulse current (A), and Pulse on time (T) are considered as machine control variables (MCV) and material removal rate (MRR) and electrode wear rate (EWR) as measured machining performance. Experiments have been designed with the assistance of the Taguchi technique and further, Taguchi-Grey Relational Analysis (T-GRA) is executed to optimize the MCV. Parametric analysis is carried out to observe the implications of MCV on the measured machining performance. After interpretation the observations, it has been analyzed that the factors A, V, and T influenced 63.71%, 13.26%, and 10.88%, respectively, on the optimal explication. The fittest method positions have been confirmed by conducting a validation test. It has been explicitly proved that multiple performance characteristics in the DS-EDM method have been considerably enhanced by the T-GRA technique. The rise in grey relational grade is 0.086 by using the T-GRA technique.

Different strategies for improving the energy efficiency of a power hydraulic system have been reviewed in this article. The energy-saving scheme is classified into three categories: System design, Improving components or product functions and Loss reduction. The sub-categories of energy-saving strategies are discussed briefly. Also, different energy-saving potentials of power hydraulic system are presented in tabular form for clear understanding on the chronological development toward energy-efficient fluid power system.

This article highlights the dynamic analysis of a proportional valve controlled hydrostatic drive. Such drives are used widely in construction and mining applications. In the drive considered for the analysis, the speed of a bent-axis hydro-motor is controlled by varying flow supplied through a proportional direction controlled valve. A non-linear mathematical model using bond graph simulation technique is developed, where detailed model of the drive system including its loading arrangement is incorporated. From the test results of the pressure-flow characteristics of the valves, its port resistances are identified. Using them and taking into account various losses of the hydro-motor, the drive model is validated through experiments. The verified model is used to study the effects of the perturbations of some critical parameters on the transient responses of the hydrostatic drive through simulation. The proposed model may be useful for initial design of such drive and the development of control systems where these drives are used as actuators.