Analysis of the Impact of Geometry Modifications on the Fit of Splined Shaft Connections Manufactured Using Selected AM Methods

Broadly, understood additive manufacturing techniques expand the spectrum of production of machine parts that are used in various types of devices. However, the requirements to ensure dimensional and shape accuracy require the determination of appropriate material allowances or clearances to enable correct assembly. For the above reasons, the study presents an analysis of the impact of the assumed geometry modifications on the possibility of assembling a splined connection manufactured using selected AM techniques. The work focused on the analysis of changes in geometry resulting from the technology used. Using the Atos II Triple Scan optical measurement system and Gom Inspect software, the possibility of installation was determined for four variants of the splined shaft connection geometry, resulting from the technologies used

New Firms Formation in Medical, Creative and Agri-Food Sectors as a Function of Local Conditions and Budget Policy of Polish Communes

Theoretical background: The article will help to answer the question what factors contribute to the emergence of new companies in medical, agri-food and creative sectors. Moreover, the aim of the article is to examine to what extent the budget policy of communes determines the creation of new enterprises in each of the analysed sectors separately.Purpose of the article: The aim of the article is to examine the factors affecting new firms formation in medical, agri-food and creative sectors in Poland, as well as the impact of budget policy of local government units at commune level on entrepreneurship in chosen sectors.Research methods: The study was conducted by means of a panel econometric model. In particular, the study was based on FEM estimation modelling based on 2,477 communes in the years 2010–2021.Main findings: The conducted research confirmed that different factors affect new firms formation in studied sectors. The research proved that budget policy of communes influences new firms formation. Moreover, the study confirmed that individual elements of the local budget policy have a different impact on each economic activity. Thus, local budget policy should be profiled in terms of type of activity supported

Increased Spending on Health Care and the Prospect of Developing a Private Health Care Sector

Ochrona zdrowia jest jednym z najważniejszych obszarów polityki społecznej każdego państwa. Choć usługi medyczne z uwagi na swój charakter mogą istnieć jako dobra prywatne, w większości krajów świadczenia zdrowotne są, w mniejszym lub większym stopniu, dostarczane przez sektor publiczny i wykorzystywane zbiorowo przez społeczeństwo. Celem niniejszego artykułu jest analiza wydatków na ochronę zdrowia w Polsce, ze szczególnym uwzględnieniem finansowania ochrony zdrowia w ramach sektora publicznego oraz prywatnego. Za hipotezę przyjęto, iż wzrost wydatków na ochronę zdrowia prowadzi do rozwoju prywatnego sektora opieki zdrowotnej. W wyniku wykonanej analizy wskazano, iż wzrost wydatkowania na ochronę zdrowia może się stać impulsem do rozwoju prywatnego sektora opieki zdrowotnej.Health protection is one of the most important topic of social policy of each country. Although medical services, can exist as private goods, in most countries health services are mostly provided by the public sector and used collectively by society. The purpose of this article is to analyse the healthcare expenditures in Poland, with particular emphasis on financing health care within the public and private sector. The hypothesis assumes that the increase in health care expenditure leads to the development of private health care sector. As a result of conducted analysis, it was pointed out that the increase in spending on health care could become an impulse for the development of private health care sector

Quality criterion in measuring the efficiency of health facilities

The paper describes one of the most popular methods of estimating the efficiency of health facilities – DEA (Data Envelopment Analysis). We highlight its practical and important role in examining the efficiency of health facilities. At the same time (by adopting a critical approach to the methodology), we propose to expand it with an additional quality dimension. The DEA method, enriched with the quality dimension, completes the notion of efficiency of a health facility and provides an effective measure for assessing a health facility’s performance. The proposed approach is new and it bridges the gap observed in the approach to investigating into the efficiency of health facilities

Wpływ obróbki cieplnej na właściwości mechaniczne przy rozciąganiu modyfikowanego polilaktydu przetwarzanego przyrostowo

The influence of temperature (80, 95 and 110°C) and annealing time (20, 25, 30 min) on the tensile strength and elongation at break of the modified polylactide (PLA Pro) processed by 3D printing (FFF – Fused Filament Fabrication) was investigated. The properties of PLA Pro were compared with properties of unmodified PLA and ABS. It was observed that the tensile strength was comparable for all annealed samples and was about 45 MPa. Moreover, the annealing process decreased the tensile strength of the modified PLA and increased the elongation at break, which may be related to a change in the degree of crystallinity. The modified PLA was characterized by tensile properties similar to ABS.Zbadano wpływ temperatury (80, 95 i 110°C) i czasu wygrzewania (20, 25, 30 min) na wytrzymałość na rozciąganie i wydłużenie względne przy zerwaniu modyfikowanego polilaktydu (PLA Pro) przetwarzanego metodą druku 3D (FFF – Fused Filament Fabrication). Właściwości PLA Pro porównano z właściwościami niemodyfikowanego PLA i ABS. Zaobserwowano, że wytrzymałość na rozciąganie była porównywalna dla wszystkich próbek i wynosiła około 45 MPa. Ponadto, proces wygrzewania spowodował zmniejszenie wytrzymałości na rozciąganie modyfikowanego PLA i zwiększył wydłużenie przy zerwaniu, co może być związane ze zmianą stopnia krystaliczności. Modyfikowany PLA charakteryzował się właściwościami mechanicznymi przy rozciąganiu podobnymi do ABS

Measuring the Efficiency of Polish Municipalities – Data Envelopment Analysis Approach

The aim of the paper is to build a ranking of municipalities due to their level of efficiency from the development point of view. According to the aim, it is possible to find out which indicators are crucial for the efficiency of municipalities in terms of sustainability. The research study involved DEA (Data Envelopment Analysis) approach. Conducted research study covered 2044 Polish municipalities in the year 2016. The ranking of Polish municipalities was prepared with the use of the DEA model. The DEA method made it possible to set goals for inefficient municipalities, which should follow and regularly evaluate the progress in the implementation of their aims. Inefficient municipalities can improve their efficiency following the technological example of chosen benchmarks

Static Analysis of Selected Design Solutions for Weight-Reduced Gears

The paper presents an analysis of selected design solutions for spur gears with reduced weight, in which the results obtained are compared to a solid gear without modifications. The reduction of the weight of the gears is of particular importance, among others in the automotive and aviation industries, where it reduces energy consumption, and thus CO2 emissions. It is also important to remember to maintain the required strength parameters when reducing the mass of the gear. This article focuses on the analysis of deformation and stress due to a given load on the considered weight-reduced gears. The values of the obtained static analysis results of the reduced-weight gears were also compared to the base gear

Biodegradowalne kompozyty polimerowe na osnowie polilaktydu stosowane wwybranych technologiach 3D

As part of the work, new polymer materials were used in 3D printing, which can be used in three technologies depending on the apparatus used: Fused Filament Fabrication (FFF), Melted and Extruded Manufacturing (MEM), Melt Extrusion Polymers (MEP). As part of the work, the properties of obtained polymer composites were examined. Polylactide (PLA) was used as the matrix, and powdered natural ground fillers were used as fillers: bamboo dust (PB), cork dust (PK) and wood dust (PD). In the first part of the work, filaments were received from the tested composites using the filament preparation line made by METACHEM in Torun for use in 3D printers. Samples for mechanical tests were obtained from the filaments thus received by means of an MEP printer and after granulation by injection molding. In the next part of the work, rheological, mechanical and structural properties of obtained composites were examined. It was found that the addition of natural fillers increased the fluidity of the obtained polymeric materials in the case of composite with addition of PK even by 48.73% compared to unfilled PLA. It was also observed that the composites obtained had lower Charpy impact strength, Rockwell hardness and tensile strength. Observation of the microstructure of the composites using SEM confirmed the even distribution of natural fillers in the polymer matrix, which proves well-chosen parameters of their homogenization in the polymer matrix.Otrzymano nowe materiały polimerowe do zastosowań w druku 3D, które można wykorzystywać, zależnie od stosowanego aparatu, w trzech technologiach: Fused Filament Fabrication (FFF), Melted and Extruded Manufacturing (MEM), Melt Extrusion Polymers (MEP). Zbadano właściwości wytworzonych kompozytów polimerowych. Jako osnowę zastosowano polilaktyd (PLA), a w charakterze napełniaczy użyto sproszkowanych w postaci pyłu naturalnych cząstek: bambusa (PB), korka (PK) oraz drzewnych (PD). Z badanych kompozytów otrzymano filamenty z wykorzystaniem zaprojektowanej i wykonanej przez METACHEM w Toruniu linii do wytwarzania filamentu stosowanego w drukarkach 3D. Z tak uzyskanych filamentów wykonano próbki do badań mechanicznych za pomocą drukarki MEP oraz, po zgranulowaniu, metodą wtryskiwania do formy. Zbadano właściwości reologiczne, mechaniczne oraz strukturalne otrzymanych kompozytów. Stwierdzono, że dodatek naturalnych napełniaczy spowodował zwiększenie płynności materiałów polimerowych, w wypadku kompozytu z dodatkiem PK nawet o 48.73% w stosunku do płynności nienapełnionego PLA. Stwierdzono, że otrzymane kompozyty wykazywały mniejsze: udarność według Charpy'ego, twardość według Rockwella oraz wytrzymałość przy rozciąganiu. Obserwację mikrostruktury badanych kompozytów za pomocą SEM potwierdziły równomierny rozkład cząstek naturalnych napełniaczy w osnowie polimerowej, co świadczy o dobrze dobranych parametrach procesu ich homogenizacji

Wpływ skręcania na strukturę elementów maszyn wytworzonych z materiałów polimerowych metodą druku 3D

In this work, on the example of a spline connection, the effect of 3D printing on the structure of machine elements made of polymeric materials after a torsion test was investigated. A clear influence of the type of polymer and the printing direction in the applied incremental technology [FFF (Fused Filament Fabrication) also known as FDM (Fused Deposition Modeling)] on the structure of the obtained elements was observed.W pracy, na przykładzie połączenia wielowypustowego, zbadano wpływ druku 3D na strukturę elementów maszyn wykonanych z materiałów polimerowych po próbie skręcania. Zaobserwowano wyraźny wpływ rodzaju polimeru i kierunku druku w stosowanych technologiach przyrostowych (FFF/FDM) na strukturę otrzymanych elementów

Manufacturing Elements with Small Cross-Sections of 17-4 PH Steel (1.4542) with the Application of the DMLS Additive Manufacturing Method

The application of direct metal laser sintering renders it possible to manufacture models with complex geometries. However, there are certain limits to the application of this method connected with manufacturing thin-walled cuboidal elements, as well as cylinders and holes with small diameters. The principal objective of the research was to determine the accuracy of manufacturing geometries with small cross-sections and the possibility of application in heat exchangers that are radiators with radially arranged ribs. To that end, four specimens were designed and manufactured; their geometries of representations assumed for the purpose of research (analysis) changed dimensions within the following scope: 10–0.1 mm. The specimens to be applied in the research were manufactured with 17-4 PH stainless steel (1.4542) with the application of 3D-DMLS printing and an EOS M270 printer. The measurement of accuracy was performed with the application of an optical stereomicroscope (KERN OZL-466). In addition to that, research into the chemical composition of the material, as well as the size of spherical agglomerates, was conducted with the application of a scanning electron microscope. The analysis of the chemical composition was conducted as well (after the sintering process). The analysis of the results based on the values received by means of measurements of the manufactured geometries was divided into three parts. Based on this, it is possible to conclude that the representation of models manufactured with the application of DMLS was comparable with the assumptions, and that the deviations between a nominal dimension and that received in the course of the research were within the following scope: 0–0.1 mm. At the final stage of research and based on the received results, two heat exchangers were manufactured