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Sledovanie tvorby triesky pri frézovaní
Tarasovičová, Adriána; Belán, Miroslav; Kasina, Marek; Michalik, Peter; Šomšáková, Zuzana
2011 - Slovak
Milling is one of the basic methods of machining where material is removed interrupted cut. A
characteristic feature of this operation is that the removed material hasn´t a constant section, the chip
thickness is observed. It is a variable. Therefore, medium chip thickness hm was determined. The
experiment was realized by climb milling where the chip during the machining of a lot to say. Uncoated
cutting tool was made of speed steel and the cutting speed was changed at three levels. The entire
experiment was concentrated at monitoring the formation and shaping of chip at low speeds, as part of
other experiments to be carried out at lower speeds. Three kinds of materials were machined, where
the machinability has been evaluated on the basis of the chip shaping and it was compared with
machinability according to the content of chemical elements in the material. From Groups of chips
produced in the milling of the materials were selected representative samples, which were noted of the
radius of these chips at 50 times magnification. The inaccuracy of this method mustn´t is forgotten,
because the chip thickness is not constant and there is some distortion. At the selecting the reference
material was assumed that material STN 12 050 is optimal machinability and was chosen as the
reference material. All three materials as well cultivated by the shape of chips were appeared at
cutting speed 4m.min-1. When gradually increasing the cutting speed changes occurred first and STN
14 220 material exhibited better machinability than material STN 17 241. Machinability according of
chip shaping was also confirmed by machinability content of chemical elements in the material.
According to the carbon content could be said that the STN 14 220 has better machinability, but the
chromium content makes the material tougher and so makes worse its kinetic and dynamic
machinability. Corrosion resistant steel STN 17 241 has the largest chromium content, it is tough,
therefore kinetically and dynamically machinability is worse than previous materials. If the goal was to
get a good surface quality material STN 17 241 would be in the first place thanks to the highest
manganese content. Machining was recorded using high-speed camera Phantom. For the record it
was observed the chip formation and their removal from the cutting zone. Chips were twisted into the
radius but in machining stainless steel by higher cutting speeds were recorded the highest values of
the chip radius of curvature. Observed of chip formation is more widespread in turning than milling
operations. However, it is important to follow the features of various technological operations, because
each is different and brings a deeper understanding of patterns of technological processes. Príspevok sa zaoberá tvorením a tvarovaním triesky pri frézovaní nízkymi reznými rýchlosťami.
Frézovanie bolo realizované použitím krátkej drážkovacej frézy určenej na výrobu drážok pier
o priemere 6 mm. Tvorba triesky bola sledovaná pri konštantnej hĺbke rezu a konštantnom
posuve. Rezná rýchlosť bola menená na troch úrovniach. Dané podmienky rezného procesu
boli aplikované pri frézovaní uhlíkovej ocele, mangano-chrómovej ocele a chróm-niklovej
ocele, čiže korózii odolnej. Následne bola sledovaná tvorba triesky pomocou
vysokorýchlostnej kamery.
Keywords:
frézování; tvorba třísky; poloměr zakřivení; milling; chip formation; radius of curvature
Available in digital repository of ZČU.
Sledovanie tvorby triesky pri frézovaní
Milling is one of the basic methods of machining where material is removed interrupted cut. A characteristic feature of this operation is that the removed material hasn´t a constant section, the ...
Problematika opotrebenia pri 5-osovom frézovaní
Pokorný, Peter; Kubek, Andrej
2011 - Slovak
CNC frézovanie je v súčasnosti jednou z najrozšírenejších technológii obrábania
tvarových plôch, pretože ponúka veľmi vysokú mieru efektívnosti. Táto efektívnosť je okrem
iného závislá aj na opotrebovaní nástrojov pri obrábaní.
Tento článok sa zaoberá problematikou frézovania tvarových plôch prostredníctvom 5 –
tich súvisle riadených osí CNC frézovačky. Je tu načrtnutá problematika opotrebovania
nástrojov pri 5 – osovom frézovaní. V závere sú uvedené hlavné smery pokračovania výskumu
v oblasti opotrebovania rezných nástrojov pri 5 – osovom frézovaní. CNC milling is currently one of the most used technology of FFS (free form surfaces)
machining, because it guarantees high effectivness of production process and quality of workpieces.
Current requirements on quality and production are pushing forward 5-axes machining centres, which
have long range of advantages. Effectiveness of these systems is dependant, besides other things, on
durability of tools. One way of enhancing tool durability is the metallurgy or by change of
technological parameters. In my research I will be focusing on much less discussed topic which is
possibility of lowering tool wear by choosing appropriate milling strategy. With 5-axes milling
machines while considering finishing methods of machining we use milling with ball nose cutters and
this particularly gives us options for further researching impact of choosing strategy of milling on wear
of the tool.
In this article I describe wear of tools and teoretical aspects of milling with ball nose cutter.
Keywords:
opotřebení; 5-osé frézovanie; tool wear; 5‐axis milling
Available in digital repository of ZČU.
Problematika opotrebenia pri 5-osovom frézovaní
CNC frézovanie je v súčasnosti jednou z najrozšírenejších technológii obrábania tvarových plôch, pretože ponúka veľmi vysokú mieru efektívnosti. Táto efektívnosť je okrem iného závislá aj na ...
K vymedzeniu predmetu sociálnej politiky
Konečný, Stanislav
2011 - Slovak
The article deals with defining of the object of social policy. Classifies the most common approaches to the definition and evaluates them. Regarded as the best option for the definition of the object of social policy is through the categories of social contingency and extends the definition of the (social) contingency with cases where this is not covered by the laws and intervention by the state.
Keywords:
social policy; object of social policy; keyword of social policy; (social) contingency
Available in the UPCE Library.
K vymedzeniu predmetu sociálnej politiky
The article deals with defining of the object of social policy. Classifies the most common approaches to the definition and evaluates them. Regarded as the best option for the definition of the object ...
Nezamestnanosť a podpora uplatnenia absolventov na trhu práce
Husáková, Mária; Pechová, Michaela
2011 - Slovak
On the development of unemployment in 2009, worked several factors that were associated with the global economic crisis. Big problem is the long term unemployment. The Slovak Republic in December 2010 recorded 48.44 percent of job seekers registered at employment office for more than one year. A big problem in the labor market are young people and its placement . Graduate experience as one of the active labor market measures assist the unemployed graduates in the age of 25 years.
Keywords:
unemployment; young people; long term unemployment; graduate practice; active labor market measures
Available in the UPCE Library.
Nezamestnanosť a podpora uplatnenia absolventov na trhu práce
On the development of unemployment in 2009, worked several factors that were associated with the global economic crisis. Big problem is the long term unemployment. The Slovak Republic in December 2010 ...
Implementácia poznatkov CAD systémv pre návrh tvárniaceho pracoviska
Sobotová, Lýdia; Dulebová, Ľudmila
2011 - Slovak
Application of CA systems in enterprises, development of new materials and testing their
properties is currently very actual topic. It does improvement of production, shortening the
product development time. It reduces costs in the simulation and testing of new products.The
aim of contribution is to make 3D model of automatic lines for production of sanitary techniques.
Keywords:
automatizované linky; Pro/ ENGINEER; vytvoření dílny; automated line; Pro/ ENGINEER; forming workshop
Available in digital repository of ZČU.
Implementácia poznatkov CAD systémv pre návrh tvárniaceho pracoviska
Application of CA systems in enterprises, development of new materials and testing their properties is currently very actual topic. It does improvement of production, shortening the product ...
Verifikácia vplyvu povlakov fréz na ich životnosť
Kasina, Marek; Tarasovičová, Adriana; Šomšáková, Zuzana; Michalik, Peter; Belán, Miroslav
2011 - Slovak
For application of new cutting tools into the praxis or for determination of their further
development it is necessary to know their cutting properties. They are also important from the view of
their economical handling. Beside that these properties serve as good and complex indicator in system
of quality and reliability of cutting tools. Paper describes problems of tool wear and verification of tool
lifespan. It is focused to testing of HSS grooving mills. At the beginning it brings theoretical knowledge
from the field of HSS and describes advantages and disadvantages of long-term experiment. In practical
part it describes the test that was used for HSS grooving cutters. Tests were realized as long-term
experiments which are more accurate but more time demanding with higher consumption of material.
During measuring of tool wear the cutting needs to be interrupted so we could cut in discrete intervals.
Three types of HSS grooving mills were used with two jags and diameter of 6 mm. One type was
coatless and two other types with coating AlTiN and AlTiSiN. As machined material there was steel STN
17 241, EN X5CRNi 18-10, that is austenitic chromium-nickel steel with very good corrosion resistance,
cold plasticity and weldability. Experiment was realized on CNC machining center HAAS VF- 1B, that is
located in laboratory of Cracow Polytechnics. Published graphs show that after use of coatless HSS
steels labeled as „A“ the lowest lifespan was reached, as the mills lasted in action for shortest time. After
use of mills with coating AlTiN S labeled as „B“ the influence of coating was observed in achieving of
double lifespan. Longest action and thus best lifespan, what can be seen on graph C, was reached after
use of HSS mills with coating AlTiSiN labeled as „C“, with threefold time period in comparison to
coatless „A“ mills. Príspevok sa zaoberá overovaním životnosti frézovacích nástrojov. V experimente boli použité tri
druhy HSS drážkovacích fréz s dvoma zubmi, s priemerom 6 mm. Jeden druh bol bez povlaku a
ďalšie dva druhy boli povlakované špeciálnymi povlakmi. Experiment bol vykonávaný formou
dlhodobých skúšok trvanlivosti, ktoré boli štatisticky spracované a následne vyhodnotené.
Keywords:
životnost; HSS; dlouhodobé zkoušky; povlaky; service life; HSS; long-term tests; coatings
Available in digital repository of ZČU.
Verifikácia vplyvu povlakov fréz na ich životnosť
For application of new cutting tools into the praxis or for determination of their further development it is necessary to know their cutting properties. They are also important from the view ...
Zvyšovanie efektívnosti technologickej komunikácie
Monka, Peter; Monková, Katarína
2011 - Slovak
Pre-production activities, which use the descriptive method, are very important with respect to their
outstanding possibilities of influencing the entire production costs of a planned product.
Its usage is adequate mainly due to the economic pressure of competition forcing the producers to
often comply with the contradictory demands, e.g. to bring high-quality products matching the
customer demand in a small number with short marketing time without increasing the price.
The article deals with possibilities of technological communication among companies in production
chain regarding to efficiency of multilateral manufacturing information providing. There is pointing out
advantages of sharing of some production data and processing of them all in information system.
Method of multi-variant process planning is introducing by basic properties. By help this method can
be preparing of processes, technological and manufacturing documentation very advantageously for
making good decisions in short periods. Manufacturing units can be more flexible by using of this way
of process plan design. The describe technique was applied in real manufacturing conditions at
product consist from a few thousand parts.
Established solution serves the purpose of easier and faster assigning of the process parameters,
shortening of the computer aided process planning documentation time in real production conditions,
and it also supports the effective utilization of the production plant based on the model mathematical
description of object variation of the computer aided process planning, fulfilling the combination of the
required characteristics within the given production conditions. Output system data can be used for
processing of the details for the warehouse, economic and wage records as for their control and
optimization. Predvýrobné aktivity sú veľmi dôležité z hľadiska veľmi výraznej možností ovplyvnenia
všetkých prvkov tvoriacich celkovú výrobnú cenu plánovaného výrobku. Nasledujúce etapy až
po predaj výrobku konečnému zákazníkovi a popredajnú starostlivosť – ktoré sú priamym
pokračovaním predvýrobnej fázy - sú však rovnako významné pre dobré postavenie
producenta na trhu. Všetky činnosti potrebné pre efektívnu prácu všetkých krokov v celom
tomto reťazci si však vyžadujú zdieľanie kľúčových informácií.
Príspevok predstavuje výsledky práce autorov pri výskume zameranom na počítačovú podporu
technologických činností, v rámci ktorého bola vyvinutá multivariantná metóda tvorby
výrobných postupov.
Príspevok je vytvorený za podpory Ministerstva školstva SR prostredníctvom grantu VEGA
1/0885/10.
Keywords:
efektivita; komunikace; informačný systém; efficiency; communication; information system
Available in digital repository of ZČU.
Zvyšovanie efektívnosti technologickej komunikácie
Pre-production activities, which use the descriptive method, are very important with respect to their outstanding possibilities of influencing the entire production costs of a planned product. Its ...
Realizcia vzdialeného reálneho experimentu s využitím technických prvkov automatizačnej priemyselnej praxe
Kuna, Peter
2011 - Slovak
Návrh, vytvorenie a aplikácia softvérových prostriedkov pre použitie PLC riadiceho systému pri realizácii vzdialeného reálneho experimentu. Overenie účinnosti a príprava vytvorených prostriedkov pre použitie v priemyselnej praxi. Design, creating and application software tools for using PLC control system in the realization remote real experiment. Verification efficiency and adaptation the news components for utilization in automation practice.
Keywords:
PLC; didaktická pomůcka; PLC; didactic tool
Available in the ZČU Library.
Realizcia vzdialeného reálneho experimentu s využitím technických prvkov automatizačnej priemyselnej praxe
Návrh, vytvorenie a aplikácia softvérových prostriedkov pre použitie PLC riadiceho systému pri realizácii vzdialeného reálneho experimentu. Overenie účinnosti a príprava vytvorených prostriedkov pre ...
Nové trendy při prepúšťaní zamestnancov
Grenčíková, Adriana; Španková, Jana
2011 - Slovak
Outplacement, as a voluntary form of consultancy to employee after sacking, is also applied and provided by companies in our conditions. This support increases the chance of being employed again, the opportunity of obtaining a view of options in the labour market, information and skills. Of course, it also needed to entertain
advantages and disadvantages by an employer, especially those ones of economic nature. On the other hand, it is also a kind of image shaping.
Keywords:
outplacement; personnel work; human resources; redundancy; strategic planning
Available in the UPCE Library.
Nové trendy při prepúšťaní zamestnancov
Outplacement, as a voluntary form of consultancy to employee after sacking, is also applied and provided by companies in our conditions. This support increases the chance of being employed again, the ...
Sociálna rovina podnikania
Mura, Ladislav
2011 - Slovak
Social entrepreneurship is in Slovak conditions relatively new area of economical activities. The basic philosophy of social entrepreneurship is a connection of bussines initiative to the aim to safisfy the social needs of regions and society.
Special sense has this kind of enterprising in localities, where is a need a paralel
assurance of not only economical but the social development too. The article is dealing with selected questions of mentioned theme.
Keywords:
entrepreneurship; social development; social enterprise; social economy; region
Available in the UPCE Library.
Sociálna rovina podnikania
Social entrepreneurship is in Slovak conditions relatively new area of economical activities. The basic philosophy of social entrepreneurship is a connection of bussines initiative to the aim to ...
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