Vol 8, No 2-2 (2014)

The modern power hydraulic actuators which have found the broadest application in various areas of equipment, often perform so responsible functions that safety of machines operation depends on their reliability. The review of existing hydraulic systems of load-lifting devices showed that practically all of them have the same schematic hydraulic diagram which main disadvantage is the low reliability that quite often leads to emergence situations even including humans death. This paper develops recommendations about the increase of reliability of such devices due to reservation of units and knots of hydraulic systems.

Material of workpiece and structural parameters of the device for combination of machining and surface plastic deformation have a significant effect on surface roughness of unstable components such as hollow cylinder.

Paper shows a way to design the cutting part of geometrically-complex tools, based on the provisions of a Boolean algebra with the ability to create a virtual equivalent of grinding equipment. It allows at the initial stage to obtain information about final product with the ability to change its parameters.

The article considers the issues of optimizing the layout of multi-axis machine tools for multi-dimensional processing using various criteria. Optimization of layouts is implemented using CAD/CAM/CAE/PDM systems, SolidWorks and MS Excel.

The article considers conditions of worm milling cutters engagement with the profile of the teeth of the cylindrical wheel when involute. The construction of modular and integral worm cutters is described. Cutting conditions are analyzed: cutting speed and axial flow.

Modern mechanical engineering is impossible without information technology. The machines are representatives of the symbiosis of mechanics and electronics. Despite of the abundance of software for calculations, solutions often do not coincide with the real test. A method is developed to determine the effect of vibration on the cutting process, which allows to solve some of the appearing problems.

There is presented the development of the experimental thermal booth for research and model (similar to full-scale) testing of materials and coatings for simulating complex heat transfer with a substantial portion of the radiant components in various types of combustion chambers during operation turbine elements, a variety of heat and power units, aero-space vehicles.

The paper presents results of research on abrasive wear of the coating WOKA PTA-6040 formed by plasma powder welding with arc currents 70A, 85A and 100A. Some patterns of wear of the deposited material due to the peculiarities of distribution in it of carbide phase at various currents of plasma arc are identified. The changes of the microstructure, the height of the elemental composition of the deposited layer, as well as sedimentation process of carbides are underlined and their effect on the wear resistance of the deposited material is shown.

The paper presents one of the methods of nonproductive machine time optimization of tools during milling of parts with complex surfaces on combined machine. In particular, there was described an algorithm to minimize the idle movements of spherocylindrical and conical cutters. Calculations were performed on the test parts with complex surfaces.

The paper discusses the rational properties of a solid alloy, greatly enhancing efficiency of nanoscale multilayer-composite coating (NMCC), deposited on the working surface of the tool. A balanced combination of properties of solid alloy and NMCC significantly improved lifecycle of tool, when machining heat-resistant nickel alloy.

The article discusses the application of the surfaces micro-arc oxidation competitive method for parts made of titanium alloys.