Table of Contents

  • MACHINES

    • Dual fuel four stroke lean burn engine supercharging system operational features

      pg(s) 263-266

      In the present publication are considered the features of the dual fuel four stroke lean burn engines supercharging system operational features. The supercharging system control means are analysed and performance data is collected from an engine in operation on an offshore vessel. The data obtained from the engine in operation is analysed, processed and figures of related parameters are obtained. The latter are analysed in relation to the importance of the supercharging technical condition. Conclusions and recommendations are stated as a final outcome.

  • TECHNOLOGIES

  • MATERIALS

    • The Effect of Vanadium, Niobium and Boron on Microstructure, Mechanical and Corrosion Properties of High-Chromium White Cast Irons

      pg(s) 286-289

      The influence of the vanadium, niobium and boron addition on properties of high-chromium white cast iron alloys for grinding balls is investigated in this paper. These alloying elements were individually added to the high-chromium white cast iron alloys with monitoring of changes in microstructure, corrosion rate, and mechanical properties in the as-cast conditions. The microstructure in all tested alloys consists of primary austenite dendrites and eutectic colonies, which consist of M7C3 carbides and austenite. The addition of V, Nb or B affects, to a greater or lesser extent, the size, morphology and volume fraction of both primary austenite dendrites and eutectic colonies. Samples of iron alloyed with vanadium and boron have a much finer structure than unmodified (base) alloy and niobium alloyed iron sample. Vanadium affects the decrease in the volume fraction of the primary austenitic phase, and the increase in the volume fraction of eutectic colonies, and thus the eutectic carbide phase in hypoeutectic alloys of high-chromium iron. The tested alloys have a comparable values of average hardness in the cross section of cast balls, as well as compressive yield strength, noting that the addition of vanadium increases the hardness, while boron addition increases the compressive yield stress. The single addition of all of three tested alloying elements shifts the corrosion potentials (and Tafel curves) of modified high-chromium white irons toward less negative values. The most favorable values of mechanical and corrosion properties were measured for the iron modified with 0.021 % of boron.

    • Nanodisperse modifiers produced by the shs method for composite materials of automotive equipment

      pg(s) 290-292

      The object of the study was carbon particles obtained by the method of self-propagating high-temperature synthesis. The purpose of the work is the development of compositions and technologies for obtaining competitive composite materials modified with low-dimensional carbon modifiers based on vegetable raw materials.

    • New regulations on the formaldehyde emission from wood-based panels

      pg(s) 293-295

      Formaldehyde is considered a health hazard, hence the wood-based panels must be within the limits imposed by the strictest regulations regarding the formaldehyde release. New national and international international regulations of formaldehyde emission from wood-based panels widely used in furniture industry were investigated in this study. The results of the study can be useful for the woodbased panel factories to follow the standards and regulations in terms of formaldehyde emission.