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Abstract

Today’s industry relies not only on raw material processing, but also on information. The huge amount of data obtained during the production process of goods and services; as well as information about the context of the production processes has made it necessary to account for, methodize, analyze and react in order to achieve a competitive market share. Fortunately, this technological leap has been able to support the above process, but the presence of those new technologies requires adequate preparation from the point of view of human resources too.

Abstract

In this paper we present laboratory equipment for illustrating the operation of spraying nozzles. It is also suitable for studying the basic processes of spraying and for measuring and evaluating the methods used in the control of sprayers. The equipment allows the monitoring of the spray film formed by the nozzles, measuring the yield of the nozzle and determining the size of the droplets formed. In the dissertation, we explore the factors influencing the droplet size. We compare the average diameter of droplets formed by the three hydraulic principle nozzles. Based on the average droplet diameters, the operation of the spray nozzles is analyzed and conclusions are drawn.

Abstract

The impact of machine feed rates of Wire Electric Discharge Machining on the kerf-width (K-width), material-removal-rate (MR-R), and surface-roughness (S-R) in the machining of Al/SiC composite is practically analysed. The relation among the feed rates of machine and K-width, MR-R, S-R is graphically acquired. It is demonstrated that lesser rate of feed is responsible for generation of larger K-width, lesser MR-R, and good finish as compared to more feed rate.

Abstract

The article presents some results of a larger study of crisis management in the automotive supply industry. This paper studies human - machine communication during organizational crises, an issue that can make the difference between success and failure. The topic is even more challenging in the highly standardized and regulated automotive industry. Using some methodologies taken from social sciences, we analyse the manner in which employees in the automotive supply industry handle unforeseen events. In spite of the increased number of standards and regulations, employees display ambiguous behaviour during unforeseen events, affecting trust in human-machine communication.

Abstract

Corrosion and corrosion-fatigue tests of the material of the pipeline, which was in operation for 41 years. It has been shown that prolonged operation reduces the parameters of resistance to fatigue and prolonged static loading in corrosive environments. It was established that the degradation of physical and mechanical properties is insignificant, Ukraine’s main gas pipelines are ready to operate at full capacity provided that timely monitoring measures are carried out.

Abstract

The technique of obtaining a hyperboloidal gear engagement with linear contact between a cylindrical involute wheel and a hyperboloid producing worm is considered. The resulting cutting tool greatly simplifies the manufacturing technology of hyperboloid worms and hyperboloid gears along with improved accuracy and roughness of the machined teeth and lower manufacturing costs.

Abstract

In order to study the strength of the proposed rope threaded joint for machine parts made of reinforced composite materials, a modeling of a stress-strain state was conducted using the software of finite-element analysis LS-DYNA. Stress-strain state modeling was conducted for a rope threaded joint, affecting on the main performance parameters considered to be p – thread pitch (p = 4 mm), and t – thread depth (t = 1 mm). The main thread parameters taken for the model were up to the metric thread М6 (ISO 724:1993) parameters.

Abstract

The paper deals with Finite difference Method of solving a boundary value problem involving a coupled pair of system of Ordinary Differential Equations. A novel iterative scheme is given for solving the Finite Difference Equations. Quasi-linearization used to convert a nonlinear problem into a series of linear problems. A problem from a flow of a nanofluid is presented as an example.

Abstract

This paper deals with the geometric built-up of a theoretically profile errorless shaper cutter. Its proposed rake face is a cylindrical surface for each tooth. The setting parameters of this are the axis inclination angle and the grinding wheel’s radius. The possible domain of the setting parameters is computed from geometrical restrictive conditions. The proposed numerical evaluation consists in the computing of the orthogonal rake angle variation, together with the deviation of the generating pro-file from the perfect involute. The obtained results allow the formulation of some conclusions regarding the influence of the cylinder radius and the axis inclination: the best rake angle distributions are obtained when using increased radius values, while profile deviation becomes minimal when using smaller radii and axis inclination angles.

Abstract

Nickel Titanium (NiTi) alloys are the class of smart materials classified under shape memory alloys. The traditional machining of these alloys is hard because of various inherent mechanical characteristics of these alloys. Therefore, non-traditional machining process such as wire electro discharge machining (WEDM) has been employed for machining of such alloys. The present study is focused on multi-performance characteristic simultaneous optimization of WEDM process parameters, in which three system control factors, namely, pulse on time (TON), pulse off time (TOFF) and wire feed (WF) are considered for simultaneously maximizing material removal rate (MRR), while minimizing surface roughness (SR) and tool wear rate (TWR). The simultaneous optimization is performed using Taguchi’s Quality Loss Function. Analysis of means and analysis of variance have been carried out to identify the significance level of each system control factor. The different levels of settings and the optimized setting have been analysed using scanning electron microscope images for surface morphological studies. The multi-response optimization investigations revealed that TON is the major contributing factor and optimal performance values were obtained at TON of 125μs, TOFF of 25μs and at WF of 4 m/min.