A number of methods utilizing external forces have been applied to induce fluid flow during solidification of molten metal in casting and welding processes. These include mould rotation, mechanical vibration and electromagnetic stirring. Many articles describe the benefits of vibration during casting and welding on microstructure and mechanical properties of castings and weldments. In this paper, these effects are reviewed and discussed to provide a better understanding of the processes. Understanding of these processes and application of the procedures offer extensive scope for significant cost savings in design and fabrication of cast and welded products.

Growing performance demands in the mechanical manufacturing field have lead to a great development of the machine tools domain, regarding especially the productivity and the manufacturing precision. When equipping a machine tool with an automatic tool changer and an automatic pallet mechanism, the obtained result is a machining center. For small series products, milling machining centers fulfill the precision and productivity requirements, through the advantages of a reduced auxiliary time and reduced operating errors. This paper presents a new technical solution of the rotary table indexing mechanism used on milling machining centers, which offers a very high positioning precision, by using a curvic coupling and a hydraulically driven table clamp/unclamp mechanism.

A comparative analysis has been carried out on two options of three-phase parametric current sources (inductive-capacitive stabilizers). Their capacities to operate in voltage stabilizer mode have been studied. Such capacities were proven and their conditions were defined. Theoretical results were experimentally checked and confirmed with satisfactory accuracy. Based on theoretical and experimental studies it was proven that the considered systems can operate in both modes – as current and voltage stabilizers.

The paper’s subject is highly topical, is very interesting from scientific point of view but also very complex. The authors propose to study the elastic structures of the cranes on basis of the similarity criteria, for this purpose the two basis criteria are shortly presented: Hooke and Cauchy. One underlines that the gantry and the half gantry cranes work outside, being subjected to actions as time changing loads; under these circumstances one needs a special check of the crane’s stability. The basic study is that one based on the analysis with finite elements, using ABAQUS software – an advanced software with highly efficient possibilities of modeling. By graphical post processing are presented the equivalent fields of stresses von Mises and of deformations.

The experiments are achieved after a preliminary analysis of the potential failure zones of the crane is done. The achievement of the experiments is based on the following logical structure of the experiment: the preparation of the measurement devices and of the used transducers, the achievement of an assembling diagram, the establishment of the quantities (parameters) which will be recorded, the execution of the mounting and of the experimental determinations, the presentation of diagrams and/or tables, conclusions, comparisons to the theoretical data established in the former paper. The paper presents the field of stresses and sectional strains in windbracings.

In order to shorten the auxiliary times regarding tool and workpiece changing, conventional machine tools are equipped with automatic tool changers and automatic pallet changers, thus becoming machining centers. Reducing the time consumed with the change of the workpiece to follow in machining implies the existence of another table – i.e. the pallet – on which the workpiece is positioned and clamped, while on the working area of the machine another part is manufactured. This paper is presenting a new automatic pallet changer mechanism which is hydraulically driven, along with its guiding and transmission systems.

In this work it was performed a fluid flow study of cooling systems for metal cutting. The study of forces resulting from the impact of fluid jets and when fluids are diverted round through the nozzle involves the application of pressure forces. The forces are determined by calculating the change of momentum of the flowing fluids. It was performed a simulation of the flow through a nozzle commonly used for pressure cooling of the cutting zone.

Optimization methods of machining processes are tools for improving product quality and reducing cost and production time. Modern optimization methods, among which genetic algorithms (GA) have been, used a lot during last two decades. This paper describes the optimization of machining processes by using genetic algorithms. Optimal parameters of machining (cutting speed and feed) were determined. Also, minimal cost for the turning process was achieved.

The paper presents the most important aspects regarding the low swirl combustion system (LSC), the design of the low swirl burner (LSB), the development and technological transfer stages from the lab-testing burner to the burners used in the high power gas turbines. The development of this low swirl combustion technology was required by the bigger and bigger constraints on the burning equipments that use fossil fuels, regarding the reduction of pollutant emissions. The low swirl combustion technology is an easy and cheap way to ensure the efficient combustion of the fossil fuels with a low level of pollutant emissions.

Flameless combustion, or moderate or intense low oxygen dilution combustion, is an advanced technology that meets all the conditions for being an important actor in the researchers’ efforts to develop low level of polluting emissions and high thermic efficiency combustion systems. Because all the factors that contribute to the emerge of this kind of combustion are not completely understood, there is the suspicion that this type of combustion could be achieved only by overheating the combustion air, which generates the limitation of this technology’s application area. After all the last years conducted research, it came to the conclusion that the requirements for this combustion are less severe than they were believed to be. The recent research is conducted towards the use of this type of combustion for all type of fuels, gas, liquid and solid.

The raw water treatment using coagulant and ultrasound indicates a faster decrease of turbidity. The main water indicators - pH dynamics and dissolved oxygen content are also presented and discussed. The dose of aluminum sulphate, actually the most widely used coagulant, decreases 8 times at the use of ultrasound waves, which represents an economy of chemicals for the water plants.