Automatic identification of causal knowledge and causal graphs in technical systems of process ventilators

U ovom radu je dan pristup automatskog računarskog identificiranja uzročnog znanja i uzročnih grafova putem monitoringa vibracija i temperatura postrojenja procesnih ventilatora velikih snaga i velikih brzina vrtnje. Predstavljena je metoda Granger-ove uzročne analize uzročnih veza mjernih parametara vibracija i temperature. Ova metoda poboljšava dijagnostiku procesnih ventilatora zbog identifikacije uzročnih zakonitosti parametara vibracija i temperatura u dijagramskom obliku. Nakon računanja i crtanja uzročnog grafa za vibracije i temperature, računa se uzročna gustoća, kao mjera dinamičke složenosti sustava. Numeričke vrijednosti uzročne gustoće se uzimaju kao indikatori sustavnog "zdravlja" procesnih ventilatora.This research paper presents the approach of automated computerized identification of causal knowledge and causal graphs using monitoring of vibrations and temperatures of sliding bearings of high-power and high-speed process ventilators. Method of Granger causal connectivity analysis of vibration and temperature parameters is presented. This method improves diagnostics of process ventilators because of identification of causal relations and links of vibrations and temperatures in graph form. After computing and plotting causal graphs for vibrations and temperatures, causal density is computed as a measure of dynamical complexity of system. Numerical values of causal density are taken as indicators of systems "health" of process ventilators

INFLUENCE OF BORON, ZIRCONIUM, AND TELLURIUM ON THE IMPACT TOUGHNESS OF X8CrNiS18-9 STEEL

Steel X8CrNiS18-9 (standard EN 10088-3: 2005) is the most commonly used from the group of austenitic stainless steel in terms of machinability. The content of sulphur present in the steel from 0,15 to 0,35% has the exclusive task to improve the machinability. However, while sulphur improves machinability it simultaneously reduces the resistance of steel to corrosion but also affects the decrease in mechanical properties particularly steel toughness. Due to its harmful effect on the steel, as well as the fact that the non-metallic inclusions are insufficiently tested for this type of high-alloy steel the aim of this study is to determine the appropriate microalloying possibility to modify the non-metallic inclusions. The aim of this work is that explore the influence of boron, zirconium, and tellurium on the impact toughness of the mentioned steel. Change of impact toughness, depending on the chemical composition of the steel is simulated with the Matlab program

PROPERTIES OF AUSTENITE STAINLESS STEEL MICROALLOYED WITH TELLURIUM AND ZIRCONIUM

Stainless steel X8CrNiS18-9 (standard EN 10088-3: 2005) is the most commonly used austenitic stainless steel due to its good machinability. This steel has high mechanical and working properties thanks to a complex alloying, primarily with the elements such as chromium and nickel. The content of sulphur present in the steel from 0.15 to 0.35% improves machinability. Microalloying with tellurium and zirconium (individually and in combination) in most cases leads to improved properties of this stainless steel, compared to melt without alloying additives, e.g. the melt microalloyed with tellurium and especially melt microalloyed with zirconium and tellurium has significantly better machinability compared to the melt without alloying elementsThe addition of sulphur, which is the cheapest available additive for free machining, will impair not only the transverse strength and toughness but also the corrosion resistance. However, while sulphur improves machinability at the same time decreases the mechanical properties particularly toughness. This work aims to test machinability, corrosion resistance, and mechanical properties of the mentioned steel, as well as the chemical composition of non-metallic inclusion

Trends in the Development of Machinery and Associated Technology

ABSTRACT The dynamic behavior of two-storey vibrating screens for dry sifting is measured after its installation