The article dealt with the assessment of the quality of hydraulic oil and determination of the mode of wear of the friction surfaces of Baljer & Zembrod manipulating lines through the information traces in the oils by applying tribotechnical diagnostics. We presented the assessment of the level of degradation of the oils. In addition, we presented the mode of wear of the friction surfaces washed in oil through evaluation of the qualitative and quantitative characteristics of the particles found in the oil. In detail, we focused on the application of suitable multivariate statistical methods on the data matrix. The article also presents predictive models that can sort oils into groups based on the assessment of quality of the oil and the state of the friction couples. The models can be used in research and in solving practical tasks in tribotechnical diagnostics of hydraulic fluids in woodworking equipment. Our results showed that the manipulation lines were greatly thermically stressed due to inadequate oil and machine maintenance. By correlative integration of all methods used, we could determine the real mode of the wear of the tribologic nodes of the machine. The experiment enabled the early detection of an undesirable process in the tribological node and implementation of corrective measures before the machine would break down.

Unplanned outage of extensive transport and handling equipment used between main stages of the production process has magnified negative effect on logistics of the entire company. Article introduces information about examining and assessing the level of wear of working oil charge in an extensive hydraulic system of device used for the transport and processing of wood raw material between the woodworking line aggregates. The decisive role in preventing the listed unsolicited situation has respecting the early tribodiagnostic signal through the analytical ferrography. Completion of this particle analysis by information complex from other appropriately selected diagnostic methodologies will be essential for the trend analysis of wear regime of system oil charge creation. The analysis is also a key predictive information about state of degradation of internal contact surfaces of the examined machinery.

The article deals with the experimental detection of the tribotechnical parameters for two different types of sliding bearings which are intended for operation without an additional lubrication due to the increasing requirements in ecology and environment. The dominant tribotechnical parameters of the self-lubricating bearing are the coefficient of friction and temperature. To determine these parameters, an experimental method was applied in this paper. The introductory part deals with materials of self-lubricating sliding bearings, their properties and usage. The experimental part consists of the evaluation of friction characteristics and geometric change of a surface after sliding pairs were being worn. Experimental examined sliding pairs comprise a sliding bearing and the shaft. The aim of this research was to determine the effect of radial force on tribotechnical parameters in order to predict the behavior of examined sliding bearings in real operating conditions.

Original scientific paper This article is focused on experimental research of the friction factor in sliding bearings without relubrication. The research includes study of friction factor values and their comparison depending on load and revolutions measured on sliding pairs, consisting of a sliding bearing and a shaft, without relubrication. The result of this experiment is an evidence of values measured reflecting the sliding pair actions under operation conditions. All the represented measured results and load conditions of each bearing are presented via graphs. Keywords: friction; friction factor; frictional force; normal force Ovisnost faktora trenja o opterećenju i broju okretaja kod kliznih ležaja bez ponovnog podmazivanjaIzvorni znanstveni članak Ovaj članak se bavi eksperimentalnim istraživanjem faktora trenja kod kliznih ležaja bez ponovnog podmazivanja. Istraživanje uključuje određivanje iznosa faktora trenja i usporedbu ovisno o opterećenju i broju okretaja mjerenih na kliznom paru bez ponovnog podmazivanja koji se sastoji od kliznih ležaja i vratila. Rezultat ovog pokusa je pokazatelj izmjerenih vrijednosti kliznog para u radnim uvjetima. Sve slike mjerenja i uvjeta opterećenja za svaki ležaj predstavljene su pomoću dijagrama.