The article describes the basic parts and the overall design of the laboratory machine, which can be used to measure vibrations generated by a rotating conveyor roller attached to the flattened parts of its axis in the cut-outs of the conveyor idler support. On the structurally modified support of the conveyor idler consisting of the insertion of a plastic element placed between the roller axis and the support cut-out, the vibration acceleration values of the rotating roller from symmetric analysis were measured and compared with the values from asymmetric analysis of the traditional roller axis placement in the steel support. The size of the peripheral speed of the roller was determined, during the experimental measurements, by controlling the speed of the electric motor using a frequency converter. The obtained results of the measured values of vibration velocities in three mutually perpendicular planes showed a reduction in vibration values of about 15% when using plastic holders. The paper aims to present one of the possible technical solutions that can limit the vibration values transmitted to the supporting structure of the conveyor belt, generated by the rotating casing of the conveyor roller.

This paper presents measured vibration magnitudes on the trough surface and on the frame of a laboratory model of a vibrating conveyor, detected by acceleration sensors. The vibration source is a DC asynchronous vibration motor with two discs with unbalanced masses mechanically attached to the end parts of the rotor. The trough of the vibrating conveyor is supported by four rubber springs of two types, which are characterised by considerable spring stiffness. Digital signals were recorded using the DEWESoft SIRIUSi measuring apparatus, which carries information about the magnitude of acting vibrations, which can be remotely transmitted from their place of action via a WI-FI router to the operating station, where they are subjected to a detailed computer-based analysis. From the identification and deeper analysis of the measured signals it is possible to monitor the optimum operating conditions of the vibration equipment, depending on predetermined parameters, namely, the trough inclination angle, the throw angle, the rotor speed of the vibration motor, the spring stiffness and the amount of material on the trough surface. The highest mean magnitude of the effective vibration velocity (4.8 mm·s⁻¹) in the vertical direction was measured on a model vibrating conveyor, with rubber springs with a stiffness of 54 N·mm⁻¹, with the unloaded trough without the conveyed material. The lowest mean magnitude of the effective vibration velocity was 1.2 mm·s⁻¹ in the vertical direction with a weight of 5.099 kg of conveyed material on the trough. Suitably designed rubber springs, of optimum stiffness, dampen the vibrations transmitted to the machine frame. From their sizes, it is possible to remotely monitor the working operation of the vibrating conveyor or to obtain information about the failure of one or several used rubber springs.

This paper presents the basic structural parts, a 3D model, and the overall design of a laboratory machine, which was created to detect vibrations generated by the casing of a conveyor roller rotating at different speeds. The intention of the authors was to verify whether plastic brackets inserted into the structurally modified trestles of a fixed conveyor idler can reduce the vibration values transmitted from the rotating conveyor roller to the trestle of a fixed idler. Experimental vibration measurements taken on the non-rotating parts of conveyor rollers, performed on a laboratory machine according to ISO 10816, are suitable for characterizing their operating conditions with regard to trouble-free operation. The aim of this paper is to detect the vibrations of a rotating conveyor roller on a laboratory machine in the defined places of a fixed conveyor idler and also on the steel frame of a laboratory machine that represents the supporting track of a belt conveyor. Vibrations detected by piezoelectric acceleration sensors were recorded by a measuring apparatus and displayed in the environment of Dewesoft X software (version 10). The measurements show that the vibration values grow with the increasing speed of the conveyor roller rotation. Experimental measurements have proven the correctness of the assumption that the vibrations transmitted to the trestle of a fixed conveyor idler are lower by up to 40% when using plastic brackets into which the axle of the conveyor roller is attached, compared to the solution where the axle of the conveyor roller is inserted into the notches of a steel trestle.

Insoluble contaminants and varnish, resulting from oil degradation byproducts and sometimes depleted additive molecules, are initiated primarily due to thermal stress on the oil. This poses significant challenges in tribology, particularly for the lubrication systems of modern complex machinery, leading to severe debilitating effects such as loss of operating clearances and impaired heat transfer. Addressing varnish buildup is crucial, and timely oil analysis emerges as a valuable tool, offering essential insights into the oil degradation level and the potential presence of insoluble contaminants. Among the various laboratory testing methods available to assess varnish potential, colorimetric analysis, specifically Membrane Patch Colorimetry (MPC), is widely applied owing to its efficiency and cost-effectiveness. This study extends the application of MPC test principles, commonly utilized for turbine oils, to measure insoluble contaminants generated by degraded hydraulic fluids. Adhering to the ASTM D7843-21 standard, which stipulates the precision of this testing method for turbine oils is contingent upon the sample’s incubation period, our investigation focuses on exploring modifications to the standard 72-hour incubation period. We aim to assess the viability of shortening or extending this duration for conducting MPC tests on used hydraulic fluids, thereby potentially enhancing the precision and relevance of MPC tests in hydraulic fluid analysis.

The article describes the basic parts and the overall design of the laboratory machine, which can be used to measure vibrations generated by a rotating conveyor roller attached to the flattened parts of its axis in the cut-outs of the conveyor idler support. On the structurally modified support of the conveyor idler consisting of the insertion of a plastic element placed between the roller axis and the support cut-out, the vibration acceleration values of the rotating roller were measured and compared with the values of the traditional roller axis placement in the steel support. The size of the peripheral speed of the roller was determined, during the experimental measurements, by controlling the speed of the electric motor using a frequency converter. The obtained results of the measured values of vibration velocities in three mutually perpendicular planes showed a reduction in vibration values of about 15% when using plastic holders. The paper aims to present one of the possible technical solutions that can limit the vibration values transmitted to the supporting structure of the conveyor belt, generated by the rotating casing of the conveyor roller.

The paper presents measured vibration magnitudes on the trough surface and on the frame of a laboratory model of a vibrating conveyor, detected by acceleration sensors. The vibration source is a DC asynchronous vibration motor with two discs with unbalanced masses mechanically attached to the end parts of the rotor. The trough of the vibrating conveyor is supported by four rubber springs of two types, which are characterized by considerable spring stiffness. Digital signals measured by the sensors, which carry information about the magnitude of acting vibrations, can be remotely transmitted from their place of action via a WI-FI router to the operating station, where they are subjected to the deailed computer based analysis. The highest mean magnitude of the effective vibration velocity (4.8 mm·s-1) in the vertical direction was measured on a model vibrating conveyor, with rubber springs of stiffness of 54 N·mm-1, with the unloaded trough without the conveyed material. The lowest mean magnitude of the effective vibration velocity (1.2 mm·s-1) in the vertical direction with a weight of 5.099 kg of conveyed material on the trough. Rubber springs, of optimum stiffness, dampen the vibrations transmitted to the machine frame. From their sizes, it is possible to remotely monitor the working operation of the vibrating conveyor or to obtain information about the failure of one or several used rubber springs. The paper provides guidance on how to design an optimum spring stiffness, which has a major impact on the magnitude of vibrations transmitted to the frame or foundations of a particular vibratory machine design. Measured signals from acceleration sensors detecting the magnitude of the vibration allow remote monitoring of the optimum operating condition of the vibration equipment depending on predetermined parameters, namely the trough inclination angle, the throw angle, the rotor speed of the vibration motor, the spring stiffness and the amount of material on the trough surface.