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Mechanical and mathematical research of local deformations of a steel roller shell with a variable geometry of contact surface

Abstract

The article is devoted to solving the fundamental and applied problem of nonlinear structural mechanics of machines by introducing into the drum two additional stop cylinders with supporting rollers at the end and adjustable length, providing a given elliptical or circular shape of a flexible shell with a smoothly variable geometry in the area of its contact with compacted pavement material. Compaction of soil, gravel and asphalt concrete in the sphere of road is not only an integral part of the technological process of the roadbed, road foundation and surface construction, but it is actually the main operation to ensure their strength, stability and durability. The quality, cost and speed of road construction, the possibility of using fundamentally new technologies, structures and materials is largely determined by the availability of modern road machinery.

Open access
Methods for Asssessing Energy Efficiency of Grain Dryers

Abstract

The article presents an algorithm for calculating selected energy assessment indexes for grain driers. Particular attention was paid to the conversion of the equations obtained for the operating conditions of the drying process into equations allowing the calculation of indexes for the standard drying conditions. The indexes obtained allow a proper comparison of dryers operating in varied atmospheric conditions, as well as humidity and temperature of the dried material.

Open access
Multi-criteria decision analysis for simplified evaluation of clean energy technologies

Abstract

Technology assessment (TA) is not a new concept. High value energy technology identification needs to be followed by a decision process in which all shareholders contribute. A case study on Combined and Heat Power (CHP) technologies considered is presented to illustrate the applicability of fuzzy analytical hierarchy assessment approach (FAHP). The goal of this paper is to identify and evaluate the best variant of CHP technologies using multi-criteria that are technical feasibly and cost effective reflecting performance parameters. The results depict that technology A2 with an overall ranking of 0.438 is the best alternative compared to others. Taking into consideration decision parameters for the section, A1 is found to be relatively most important with a rating of 0.434 with its reliability and cost effectiveness. The presented fuzzy-based methodology is general expected to be used by a diverse target groups in energy sectors.

Open access
On Changes in Concept and General Composition of Agricultural Tractors

Abstract

Conclusions on the analysis of the state of development in the tractor industry are formulated, aspects of the forecasting concept of transformation, general layout solutions and the theory of promising tractor units with new propulsion systems are considered, a general approach to the pre-design substantiation of new generation tractors is presented.

Open access
Problems of use of FMEA method in industrial enterprise

Abstract

Presented paper concentrate on problems connected with FMEA method usage in industrial enterprise. There is in the paper a description of the basic rules of FMEA method and competition between FMEA analysis and gap analysis. The analysis of defects has been done to find recommendations how to eliminate or restrain them. On the basis of conducted research we found that selection of staff to the team is very important factor in the FMEA analysis undertaking process. The staff should have appropriate level of knowledge about FMEA method methodology and other tools which are indispensable in the process of implementing this method within the company.

Open access
The Production Efficiency and Specific Energy Consumption During Processing of Corn Extrudates with Fresh Vegetables Addition

Abstract

The aim of the work was to determine the influence of screw speed and variable amounts of fresh vegetable additives on selected aspects of extrusion-cooking of corn-vegetable blends. Corn grit as a basic component was supplemented with a fresh pulp of beetroot, carrot, leek and onion in amounts of 2.5-10% in the recipe. The extrusion-cooking was carried out using a single-screw extruder in the temperature range 120-145°C and extrudates were formed into directly expanded snacks. Two indicators were measured: the production efficiency (Q) and the specific mechanical energy (SME) consumption. As a result of the findings it was noted that the rotational speed of the extruder’s screw showed a greater impact on both production efficiency and SME as compared to the variable amounts of applied additives. A tendency to increased efficiency and specific mechanical energy consumption was observed along with the increase of screw speed during processing. The highest production efficiency was observed if fresh leek and onion were used as additives and the highest extrusion speed screw was applied. The largest specific energy consumption was noted during the extrusion-cooking of blends containing fresh carrot and onion addition at high screw speed.

Open access
Analysis of Engine Oils from Farm Tractors in the Aspect of their Change

Abstract

The paper presents results of research on selected physico-chemical parameters of engine oils from farm tractors based on the date of their change assumed by the user. 17 samples of used engine oil from farm tractors of various producers and with a varied exploitation course were analysed. Oils for research were collected during oil change, registering the service life of oil each time. They were obtained from service points that repair farm tractors in the region of Lublin Province. The studies were to verify whether a decision concerning oil change taken by tractor users after specific time of operation of an engine was good. Number of exceedings of the threshold values of parameters of engine oil which are responsible for correct lubrication were the basis for evaluation

Open access
Analysis of Gap Measurement of Various Dimensions of SERVAQUAL Model in context to Indian Banks

Abstract

To improve the reputation and customer loyalty, a benchmarking analysis is being carried out, which influences the perception of the service quality for banks. With the expansion of competitive interactions, the results can serve as a strategic tool to gain competitive advantage and customer satisfaction. Banks reveal the expectations and expectations of customers regarding the quality of selected services. The process creates and expands its reputation and builds customer loyalty. This research aims to compare the perception of the quality of four leading banks with logical comparisons.

Open access
An analysis of the causes of track twist at high speed of driving

Abstract

The research of railway track surfaces is aimed at improving the quality of railway infrastructure and providing the chance of improving the safety of driving. Therefore, it is advisable to constantly monitor track surface, but the research itself is not innovative because it is based on a known procedure. The crucial element are the techniques that allow to delve into the sources of problems. The aim of the article is to use the selected instruments of quality management to analyze the causes of track twist at high (180 km/h) speed of driving. The analysis of the causes of track twist was done on the basis of results from the measurement of one kilometer track section of the Krakow Glowny - Medyka route, which was made by using the TEC measuring device in April 2018. It was inferred that it is impossible to reach 180 km/h without track twist. In order to identify the causes of track twist it was proposed to use the selected sequence of quality management instruments, i.e.: brainstorming, Ishikawa diagram and the 5Why method. The identified causes of track twist include the abrasion of rail, scratches and exploitation point. The analysis and conclusions drawn from it may be useful in the analysis of other problems in railway transport as well as production and service industries.

Open access
Analysis of Traction Properties and Power of Wheels Used on Various Agricultural Soils

Abstract

The paper presents results of the research on traction properties of two tractor tyres used on two agricultural grounds. The first ground was a stubble and the second one cropland. The investigated tyres had the same structure (diagonal, with a traditional tyre tread but different external dimensions. The research was carried out in field conditions with the use of a stand aggregated with a farm tractor. Analysis covered traction efficiency, slide, towing power and power lost on the rolling resistance and wheel slide. Based on the obtained results it was concluded that on a ground with lower compaction, the values of power losses were higher and traction efficiency was lower. Moreover, it was proved that the value of the power lost for rolling resistance had a decisive impact on the values of traction efficiency

Open access