scholarly journals Influence of rivet length on joint formation on self-piercing riveting process considering further process parameters

2021 ◽  
Author(s):  
Fabian Kappe ◽  
Christian Roman Bielak ◽  
Vadim Sartisson ◽  
Mathias Bobbert ◽  
Gerson Meschut
Keyword(s):  
Process Parameters ◽  
Automotive Industry ◽  
Raw Materials ◽  
Numerical Study ◽  
Research Work ◽  
High Load ◽  
Continuous Increase ◽  
Wide Range ◽  
Riveting Process ◽  
The Individual

Driven by the CO2-emission law by the European government and the increasing costs for raw materials as well as energy, the automotive industry is increasingly using multi-material constructions. This leads to a continuous increase in the use of mechanical joining techniques and especially the self-piercing riveting is of particular importance. The reason for this is the wide range of joining possibilities as well as the high load-bearing capacities of the joints. To be able to react to changing boundary conditions, like material thickness or strength variation of the sheets, research work is crucial with regard to the increase of versatility. In this paper, a numerical study of the influences on the selfpiercing riveting process is presented. For this purpose, the influence of different process parameters such as rivet length and die depth on various quality-relevant characteristics were investigated. With the help of the design of experiment, significant influences were determined and interactions between the individual parameters are shown.

New Approach for Versatile Self Piercing Riveting: Joining System and Auxiliary Part

2021 ◽  
Vol 883 ◽  
pp. 3-10
Author(s):  
Fabian Kappe ◽  
Mathias Bobbert ◽  
Gerson Meschut
Keyword(s):  
Boundary Conditions ◽  
Research Work ◽  
High Load ◽  
Continuous Increase ◽  
New Approach ◽  
Load Bearing ◽  
Mechanical Joining ◽  
Wide Range ◽  
Riveting Process

The increasing use of multi-material constructions lead to a continuous increase in the use of mechanical joining techniques due to the wide range of joining possibilities as well as the high load-bearing capacities of the joints. Nevertheless, the currently rigid tool systems are not able to react to changing boundary conditions, like changing the material-geometry-combination. Therefore research work is crucial with regard to versatile joining systems. In this paper, a new approach for a versatile self-piercing riveting process considering the joining system as well as the auxiliary joining part is presented.

scholarly journals An Overview of Semisolid Processing of Aluminium Alloys

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
M. S. Salleh ◽  
M. Z. Omar ◽  
J. Syarif ◽  
M. N. Mohammed
Keyword(s):  
Automotive Industry ◽  
Aluminium Alloys ◽  
Raw Materials ◽  
Low Cost ◽  
New Technology ◽  
Research Work ◽  
Production Method ◽  
Semisolid Processing ◽  
Shaping Process ◽  
Feedstock Production

Semisolid metal processing (SSM) or thixoforming is a new technology that offers several advantages over liquid processing and solid processing. This process utilizes semisolid behavior as well as reduces macrosegregation, porosity, and forming forces during shaping process. A lot of research work has been carried out by various researchers in order to exploit the potential of this process to produce different products especially for automotive industry. This paper will summarise the rheological behavior of aluminium alloys in semisolid slurries, thixoformability of modified aluminium alloys, the effect of feedstock production method on mechanical properties, and the importance of developing low-cost raw materials for semisolid processing.

GEOLOGICAL EDUCATION IN SOFIA UNIVERSITY – INTEGRATION OF TRADITIONS AND KNOWLEDGE IN PRACTICE

2018 ◽  
Vol 28 (3) ◽  
pp. 1093-1098
Author(s):  
Nikola Botoucharov
Keyword(s):  
Natural History ◽  
Raw Materials ◽  
Effective Interaction ◽  
Research Work ◽  
Research Priorities ◽  
Field Trips ◽  
Detailed Knowledge ◽  
Regular Form ◽  
Student Chapter ◽  
Wide Range

Sofia University “St. Kliment Ohridski” is the first Bulgarian and the highest academic institution with more than a century long educational and scientific traditions. Geology is part of the university from the very beginning in the area of Natural sciences. It is an example of the effective interaction between the educational processes and implementation of science, technology and innovation. The scientific activities of Sofia University have been developing along with the research priorities, lecture courses, field work and their implementation into practice.The degree programs in Geology were set up at the end of the 19th century, just 3 years after foundation of the Sofia University. The first lectures in Geology and Mineralogy dates back to 1891 when the Department for Natural History at the Sofia University started. They both form the basis of education and research in the field of Geology in Bulgaria. The main contribution in the beginning for the development of teaching and research belongs to remarkable scientists like Prof. Georgi Zlatarski, Prof. Georgi Bonchev, Prof. Stefan Bonchev, Prof. Lazar Vankov, Prof. Dimitar Yaranov and so many others. Faculty of Biology, Geology and Geography inherits the Faculty of Natural History, but is later divided.Faculty of Geology and Geography in Sofia University was formed in 1963 and till now the geology is studied in a regular form of education. There are Bachelor, Master and PhD degrees with duration of 8, 3 and 6 semesters respectively. The Bachelor Degree provides fundamental knowledge in all geological disciplines. The Master Degree covers a wide range of educational and scientific research work carried out in specialized, well-equipped laboratories for investigation of geological objects. PhD Degree is a basic form of organized training for highly qualified graduates in all spheres of geological science and practice.The teaching process in the Faculty focuses on the lectures and seminars, as well as on the individual forms of education – tasks, course and diploma thesis works, laboratory and field practices. The educational practices - stationary and field trips to certain geological, mining or economic sites are regularly held after the end of the summer semesters. Modern profile of Geology means that students obtain detailed knowledge on structure, tectonics, geological features, underground and surface processes of the Earth as well as regularities for the accumulation and distribution of ores, non-metalliferous raw materials, coal, oil and gas.The implementation of geological education into practice is supported by student membership in various society and sections. The specific activities focus student interests in organized working groups, participation in field trips and applied research. These non-profit organizations integrate in the best way geological traditions from the industry and knowledge from university into the future career development of young people. The Sofia University SEG Student Chapter supports student field trips with the idea to provide understanding of main geological characteristics of the visited geological sites and obtain specific skills of investigation and mining exploration. The Sofia University Student Chapter of AAPG actively contributes to student community growth, enriching educational culture and expanding geological expertise of its members in the field of Petroleum geology.

scholarly journals Exploitive properties of composites on the polymer waste from the manufacture of car windows

2018 ◽  
Vol 19 (9) ◽  
pp. 79-82
Author(s):  
Zenon Tartakowski ◽  
Maksymilian Burzyński ◽  
Katarzyna Cimander
Keyword(s):  
Automotive Industry ◽  
Raw Materials ◽  
Glass Production ◽  
High Sensitivity ◽  
Polymer Waste ◽  
Hygroscopic Properties ◽  
Wide Range ◽  
New Material ◽  
Technical Products ◽  
Properties Of Composites

In the last five years, the number of laminated glass produced in Poland for the automotive industry has almost doubled. It is the effect of increasing requirements in the area of vehicle safety and use. This also caused the increase in the amount of waste in glass production technology. The demands of circular economy require the re-use of waste as raw materials. PVB as a structural material is characterized by good mechanical properties in a wide range of positive and negative temperatures and high sensitivity to moisture (high hygroscopy). On the basis of PVB waste from the production of glass and using recyclate of polyethylene and polyester-glass dust, new material composites were made. Taking into account the hygroscopic properties of PVB, aging tests of new materials were made after exposure to them in the HHC climate. The influence of the aging process on the tested properties was determined. The results confirmed the possibility of using composites for technical products in the automotive industry.

scholarly journals Improving the Efficiency of the Vilnius City Transport System in the Context of Sustainable Mobility and Multimodality

2021 ◽  
pp. 31-46
Author(s):  
Aldona Jarašūnienė ◽  
Domas Česnulaitis
Keyword(s):  
Transport System ◽  
Social Impact ◽  
Raw Materials ◽  
Road Transport ◽  
Urban Transport ◽  
Sustainable Mobility ◽  
Continuous Increase ◽  
Traffic Jam ◽  
Long Term Effect ◽  
Wide Range

Vilnius is one of the most dynamic cities in Eastern Europe experiencing a continuous increase in the number of vehicles and the development of road transport networks associated with a wide range of environmental impacts, greenhouse gas emissions, depletion of raw materials, energy and fuel consumption and also a social impact, expressed in the quality of life of people, human health, traffic jam and economic impact because of generated losses of economic efficiency. Different strategies have been adopted by the city of Vilnius to tackle the increasing traffic flows with a modest impact and without a long-term effect. This article aims at analysing the measures taken to improve the transport system of Vilnius city and presenting different types of solution, which could improve interconnectivity of passenger transport as ways to solve the problems of the urban transport system.

A New Approach to Expanding the Identification Parameters of Fermented Beverages

2021 ◽  
pp. 29-32
Author(s):  
Сергей Азатович Хуршудян ◽  
Константин Викторович Кобелев ◽  
Ирина Михайловна Абрамова ◽  
Марина Эдуардовна Медриш
Keyword(s):  
Organic Acids ◽  
Raw Materials ◽  
Public Confidence ◽  
Measuring Instruments ◽  
Volatile Components ◽  
Input Control ◽  
Wide Range ◽  
The Individual ◽  
Composition Properties ◽  
And Control

Фальсификация пищевых продуктов насчитывает не одно столетие, что объясняется экономической выгодой ее производителей, и наносит существенный вред имиджу государства, подрывает доверие населения к добропорядочным производителям. Борьба с фальсификацией ведется на уровне различных государственных органов надзора и контроля. Наряду с законодательными мерами особое место в контроле качества и выявлении фальсификации занимают аккредитованные госорганом (Росаккредитация) испытательные лаборатории и центры, которые по результатам испытаний определяют подлинность пищевого продукта. В исследованиях используются различные методы анализа - органолептический, химический и физико-химический с использованием широкой гаммы средств измерений. Значения идентификационных параметров (состав, свойства) продукта прописаны в соответствующих стандартах на пищевые продукты, поэтому одним из важнейших этапов борьбы с фальсификацией служит выяснение зависимости подлинности и качества продукта от отдельных параметров продукта и определение их значений. Количество и значения идентификационных параметров периодически пересматриваются в связи с изменениями в технологии производства фальсификата и используемых компонентов сырья. Анализ увеличения идентификационных параметров подтверждает, что в последнее время расширение осуществлялось за счет ужесточения входного контроля сырья (качество и ассортимент) и выходного контроля готовой продукции. При этом особенности технологии производства пищевого продукта и их влияния на показатели продукта не получили должного внимания. Напитки на основе технологии брожения (вино, виски, квас и др.) обладают определенной особенностью - в процессе брожения вырабатываются летучие компоненты и органические кислоты, которые переходят в напитки. Наличие этих компонентов позволяет однозначно определять подлинность напитка. Включение содержания летучих компонентов и органических кислот в число контролируемых параметров напитка значительно расширяет возможности в борьбе с фальсификатом. Falsification of food products has more than one hundred years, due to the economic benefit of its producers, and causes significant harm to the image of the state and undermines public confidence in the integrity manufacturers. The fight against falsification is carried out at the level of various state bodies of supervision and control. In addition to legislative measures, especially in the quality control and detection of falsification take accredited bodies (Rusaccreditation) testing laboratories and centers that the results of tests to determine the authenticity of the food. In studies using different methods of analysis - the organoleptic, chemical and physico-chemical with a wide range of measuring instruments. The values of identification parameters (composition, properties) of the product registered in the corresponding standards for foods, so one of the most important stages of combating counterfeiting is to elucidate the dependence of product quality and authenticity of the individual product parameters and determine their values. The number and values of identification parameters are periodically reviewed in connection with changes in the technology of counterfeit production and used components and raw materials. The analysis of the increase in identification parameters confirms that recently the expansion was carried out due to the tightening of the input control of raw materials (quality and assortment) and the output control of finished products. In this case, particularly the production of food technology and their impact on the characteristics of the product have not received proper attention. Beverages based on fermentation technology (wine, whiskey, kvass, etc.) have a certain feature - during the fermentation process, volatile components and organic acids are produced, which pass into drinks. The presence of these components allows you to uniquely identify the authenticity of the drink. Inclusion in the number of controllable parameters of the beverage content of volatile components and the organic acids greatly enhances the fight against forgery.

scholarly journals Achievements and Trends in Biocatalytic Synthesis of Specialty Polymers from Biomass-Derived Monomers Using Lipases

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 646
Author(s):  
Anamaria Todea ◽  
Diana Maria Dreavă ◽  
Ioana Cristina Benea ◽  
Ioan Bîtcan ◽  
Francisc Peter ◽  
...  
Keyword(s):  
Green Synthesis ◽  
Process Parameters ◽  
New Technologies ◽  
Polymers And Plastics ◽  
Continuous Increase ◽  
Molecular Weights ◽  
Wide Range ◽  
Significant Process ◽  
Recent Developments

New technologies for the conversion of biomass into high-value chemicals, including polymers and plastics, is a must and a challenge. The development of green processes in the last decade involved a continuous increase of the interest towards the synthesis of polymers using in vitro biocatalysis. Among the remarkable diversity of new bio-based polymeric products meeting the criteria of sustainability, biocompatibility, and eco-friendliness, a wide range of polyesters with shorter chain length were obtained and characterized, targeting biomedical and cosmetic applications. In this review, selected examples of such specialty polymers are presented, highlighting the recent developments concerning the use of lipases, mostly in immobilized form, for the green synthesis of e-caprolactone co-polymers, polyesters with itaconate or furan units, estolides, and polyesteramides. The significant process parameters influencing the average molecular weights and other characteristics are discussed, revealing the advantages and limitations of biocatalytic processes for the synthesis of these bio-based polymers.

Microstructural characterization of laser-melted/roller-quenched dicalcium silicate

1988 ◽  
Vol 46 ◽  
pp. 582-583
Author(s):  
C. J. Chan ◽  
K. R. Venkatachari ◽  
W. M. Kriven ◽  
J. F. Young
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Shape Change ◽  
Microstructural Characterization ◽  
Particle Size Effect ◽  
Dicalcium Silicate ◽  
Laser Melting ◽  
Uniform Size ◽  
Cell Shape Change ◽  
Wide Range

Dicalcium silicate (Ca2SiO4) is a major component of Portland cement. It has also been investigated as a potential transformation toughener alternative to zirconia. It has five polymorphs: α, α'H, α'L, β and γ. Of interest is the β-to-γ transformation on cooling at about 490°C. This transformation, accompanied by a 12% volume increase and a 4.6° unit cell shape change, is analogous to the tetragonal-to-monoclinic transformation in zirconia. Due to the processing methods used, previous studies into the particle size effect were limited by a wide range of particle size distribution. In an attempt to obtain a more uniform size, a fast quench rate involving a laser-melting/roller-quenching technique was investigated.The laser-melting/roller-quenching experiment used precompacted bars of stoichiometric γ-Ca2SiO4 powder, which were synthesized from AR grade CaCO3 and SiO2xH2O. The raw materials were mixed by conventional ceramic processing techniques, and sintered at 1450°C. The dusted γ-Ca2SiO4 powder was uniaxially pressed into 0.4 cm x 0.4 cm x 4 cm bars under 34 MPa and cold isostatically pressed under 172 MPa. The γ-Ca2SiO4 bars were melted by a 10 KW-CO2 laser.

Justification of the need to improve the legal, regulatory and methodological framework for the spread of parasitic infections in the provision of medical care

2020 ◽  
Vol 99 (5) ◽  
pp. 493-497
Author(s):  
M. M. Aslanova ◽  
T. V. Gololobova ◽  
K. Yu. Kuznetsova ◽  
Tamari R. Maniya ◽  
D. V. Rakitina ◽  
...  
Keyword(s):  
Medical Care ◽  
Research Work ◽  
Hospital Environment ◽  
Parasitic Infections ◽  
Infusion Therapy ◽  
Methodological Framework ◽  
Production Environment ◽  
Medical Institutions ◽  
Medical Network ◽  
Wide Range

Introduction. The purpose of our work was to justify the need to improve the legislative, regulatory and methodological framework and preventative measures in relation to the spread of parasitic infections in the provision of medical care. There is a wide range of pathogens of parasitic infestations that are transmitted to humans through various medical manipulations and interventions carried out in various medical institutions. Contaminated care items and furnishings, medical instruments and equipment, solutions for infusion therapy, medical personnel’s clothing and hands, reusable medical products, drinking water, bedding, suture and dressing materials can serve as a major factor in the spread of parasitic infections in the provision of medical care. Purpose of research is the study of the structure and SMP of parasitic origin, circulating on the objects of the production environment in multi-profile medical and preventive institutions of stationary type in order to prevent the occurrence of their spread within medical institutions. Material and methods. The material for the study was flushes taken from the production environment in 3 multi-profile treatment and prevention institutions of inpatient type: a multi-specialty hospital, a maternity hospital and a hospital specializing in the treatment of patients with intestinal diseases for the eggs of worms and cysts of pathogenic protozoa. Results. During the 2-year monitoring of medical preventive institutions, a landscape of parasitic contamination was found to be obtained from the flushes taken from the production environment objects in the premises surveyed as part of the research work. Discussions. In the course of research, the risk of developing ISMP of parasitic origin was found to be determined by the degree of epidemiological safety of the hospital environment, the number and invasiveness of treatment and diagnostic manipulations and various medical technologies. Conclusion. It is necessary to conduct an expert assessment of regulatory and methodological documents in the field of epidemiological surveillance and sanitary and hygienic measures for the prevention of medical aid related infections of parasitic origin, to optimize the regulatory and methodological base, to develop a number of preventive measures aimed at stopping the spread of parasitic infections in the medical network.

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