Juraj Tulík

RESEARCH OF NEW ECOLOGICAL SYNTHETIC OIL-BASED FLUID

This paper presents the evaluation of a newly developing synthetic-based hydraulic fluid MOL Farm UTTO Synt, developed by MOL Group, Hungary. The fluid was subjected to a laboratory test by using a gear hydrostatic pump UD 25, which is used in the latest Zetor Fortera tractors. During the test, flow values were statistically evaluated and graphically displayed in the form of flow characteristics and the loss of flow efficiency. On the basis of laboratory test results, it can be concluded that the newly developing fluid meets the specified requirements and it is possible to continue in testing under operating conditions.

EFFECT OF ECOLOGICAL ENERGY CARRIERS ON FLOW CHARACTERISTICS OF TRACTOR HYDRAULIC PUMP

This paper deals with the effect of ecological energy carrier on flow characteristics of a hydraulic pump. A hydraulic oil MOL Farm UTTO Synt was used as an ecological energy carrier. After completing 900 engine hours, the flow efficiency of the hydraulic pump decreased by Δηpr = 1.197 %. Oil samples were taken from the agricultural tractor Zetor Forterra 114 41. These samples were subjected to an IR spectroscopy analysis in an accredited laboratory WearCheck, Hungary. The following oil properties were examined: kinematic viscosity at 40 °C, viscosity index, silicium and ferrum content.

Study of the Impact of Synthetic Fluid on the Lifetime of Hydraulic Pump

This paper deals with the lifetime test of a tractor hydraulic pump. The basic indicator of hydraulic pump lifetime is flow characteristics. This paper presents the results of the performance test of ecological hydraulic fluid. These results were subjected to statistical analysis. Based on these data, it is possible to express a minimum impact of ecological hydraulic fluid on hydraulic pump lifetime. The test was carried out in cooperation between the Department of Transport and Handling (Slovak University of Agriculture in Nitra) and Slovnaft, a.s. (joint-stock company), and supported by the Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of the Slovak Republic – VEGA, ref. No 1/0857/12.

Design of Laboratory Test Device for Evaluating the Lifetime of Hydraulic Components of Tractor Three-Point Hitch

The designed laboratory device will solve the issue of test methods of tractor hydraulics, monitoring the lifetime of hydraulic components, and testing of various oil types. The results of experimental measurements of forces and pressures in the three-point hydraulic hitch of tractor with plough allow implementing the design and simulation of operational loads of the dynamic system of tractor three-point hitch (TPH) under laboratory conditions. Theoretical and experimental works were focused on tractors. The design of test device is based on load characteristics obtained from the operation of tractor with plough. Research was focused on the use of results obtained from operational measurements of the tractor with plough and their simulation by a hydrostatic simulator under laboratory conditions. The laboratory device will enable the TPH life tests while loading with forces in the horizontal and vertical direction so that it corresponds to a practical loading process

Analysis of Synthetic Oil Samples During an Operating Test

Abstract This paper presents the results of analyses of ecological synthetic oil samples during an operating test. The operating test of oil was performed within cooperation of the Department of Transport and Handling and Slovnaft, a. s. (joint stock company). The analysis of ferrographic samples was performed in the laboratory of the department, and other analyses were done in an accredited Wearcheck Laboratory at Almásfüzitő, Hungary.

Evaluation of Inspected Vehicles in Reporting Period at Technical Inspection and Emission Control Station

Abstract Technical inspection is a fast, relatively timely and inexpensive, and particularly comprehensive assessment of the technical condition of vehicles. The technical review process includes a wide range of control actions, which are slightly different depending on the category of vehicle. The evaluation of technical inspection is mainly dependent on the type of failures that occur on a vehicle, and it is a three-graded classification by the grades A, B or C. Based on data obtained from technical inspections, it is possible to determine the current condition of the fleet of road vehicles in the Slovak Republic.

Pollution Analysis of New Synthetic Biodegradable Fluid During Durab Ility Test of Hydrostatic Pump

Abstract This paper deals with the pollution evaluation of a biodegradable fluid, which was used as a working medium during the laboratory durability test of a hydrostatic pump. There was used a new synthetic biodegradable fluid MOL Farm UTTO Synt., developed and produced by MOL Group, Hungary. The fluid should have been practically used as a universal, common gear-hydraulic filling in agricultural machines. During the test, the pollution of used fluid was evaluated on the basis of cleanliness code, filtration of solid particles and ferrography. Based on results of cleanliness code, we could monitor the course of hydrostatic pump wear. After test completion, the fluid was subjected to filtration of solid particles and ferrography, where clusters of small particles and larger particles were detected. On the basis of their surface and shape, they were included in particles of adhesive wear. By the comparison method it was found that they are bronze particles located in the bearings of the hydrostatic pump used.

Impact of Multipath GPS Signal Spreading on Precision of Us er Localization

Abstract This paper focuses on measuring the inaccuracy of localization using a global positioning system. It describes the types and causes of navigation errors as well as the impact of multipath signal spreading on determining the GPS location. The aim of the experiment is to quantify the degree of influence of GPS multipath signal spreading in urban environments compared with measurements in the open air. During the experiment, we have used a Holux M-1000C GPS device in the DGPS / SBAS mode using the EGNOS technology.