Andrzej Marczuk

Evaluation of Tribological Properties of Polymer Materials Used for Sliding Bearings in Agricultural Machinery

Abstract The continuous technological development requires the use of modern materials also in agricultural engineering. Knowledge of the characteristics of tribological materials pairs cooperating with each other is useful for developing sliding nodes of agricultural machinery. Tribological properties of materials should be assessed for selection of technological materials beyond the economic criterion. The article presents analysis of the characteristics of tribological ball-on-disc wear of polymeric materials used as sliding elements for farm machines. Tribological tests were carried out under dry friction for a polymer-metal pair, and a wear rate and friction coefficient of the sample; the signs of wear were submitted to SEM observations.

Determination of Optimal Geometric Parameters of the Windshield Device Limiting the Spray Drift by Wind in Herbicides Spraying

Abstract The objective of the paper is to determine the optimal geometric parameters of the windshield device limiting the spray drift by wind in herbicides spraying. Tests were carried out with the use of the planning methods of experiments and statistical methods of processing of the obtained results. The result of the research consisted in obtaining structural parameters of the windshield made in the shape of gratings with rectangular boards. It was found out that this device may be used at the wind speed exceeding agrotechnological sizes. The research results will be used in the work on devices protecting against wind at a precise herbicides spraying.

Development of New Technologies for Cattle Breeding Systems Taking Into Account Sustainable Environmental Conditions

Abstract Properly designed housing buildings, with regard to reduction of a negative influence on environment, are necessary for ensuring sustainable development in agriculture. The objective of this paper was to show the results of environmental conditions research on high milk yield dairy cattle in different housing systems. Temperature and relative humidity of air and concentrations of harmful gases − ammonia and carbon dioxide accompanying them were investigated.

New developments of solar energy utilization in the aspect of EU directives

Abstract Photovoltaic systems are very efficient concerning proper utilization of solar radiation. However, the nanotechnology solution can replace the photovoltaic by the use of new production technology to lower the price of solar cells to one tenth. Sun provides nearly unlimited energy resource, but existing solar energy harvesting technologies are quite expensive and cannot compete with fossil fuels. The central part of Poland, which represents about 50 percent of the area, gives solar radiation at the level of 1000 kWh·m−2/year. Other new developments, which can help improve existing efficiency of solar systems are: diatoms utilization, artificial photosynthesis, nanoleaves and rotation solar towers.

Windrow Scarifier for Rotary Mower

Abstract In order to accelerate the process of drying of grass mowed for hay and haylage there are numerous technological treatments: multiple tedding, raking in rolls and turning rolls, mechanical impact on green forage in the process of mowing by the use of presses and windrow scarifiers. Presently mechanical maceration of green forage with mowing is popular. Papilionaceous feed plants are subjected to windrow presses and graminacenous plants to beating working systems. Analysis of various devices for acceleration of the drying process of green forage proves that they are quite complex and expensive on account of considerable material consumption. In order to eliminate the faults in the Russian Scientific and Research Fodder Institute of Wiliams a completely different windrow scarifier for the rotary mower KR-2.4 M was developed. It has a simple structure and it serves for acceleration of field drying of mowed grass in loose rolls. The paper presents the results of the research on a mower with an experimental windrow scarifier

Improvement of Harvesting Methods of Perennial Seed Grass

Abstract In case of traditional harvesting methods the losses of perennial grass seeds may reach 45-50% of the biological yield in unfavourable weather conditions. The paper presents the results of comparative assessment efficiency of various methods of harvesting of perennial seed grass. It was found that the use of special devices and structures in combine harvesters allows increase of yield of technological mixture to the combine tank, degree of seed threshing to 93% and limit the losses of crop to 20-29%. Harvesting of seeds in non-waste technology with harvesting of the entire yield with later transport, drying, threshing and seeds cleaning in stationary devices results in reduction of losses by 5 to 10% but it leads to the increase of energy inputs by 24-25% in comparison to traditional with threshing method. Harvesting with a combing method of plant seeds on a trunk in „Невейки” technology results in the increase of the seeds harvesting to 86-98% of a biological yield.

THE RESEARCH ON AGEING OF GLYCOL-BASED BRAKE FLUIDS OF VEHICLES IN OPERATION

The road safety depends on many factors, including the efficiency of the technical system and the disposal of the driver of the vehicle. As wear of most of the vehicle assemblies threatened only with a breakdown, excessive wear of the braking system components may pose a risk of a traffic accident. The article presents a study on the quality of the brake fluid conductivity as a function of temperature and water content conducted for a selected group of vehicles. This group of vehicles was characterized by different production date and had a different of vehicle mileage. We presented the methodology of statistical analysis of the quality of brake fluid tests in selected 38 passenger vehicles in operation.