Wyniki 1-4 spośród 4 dla zapytania: authorDesc:"Ján MORAVEC"

Unconventional cavity forming using a machine tool DOI:10.15199/24.2016.9.11

  Niekonwencjonalne formowanie wgłębne z użyciem obrabiarek In the article attention is drawn to unconventional shaping process for the production of cavities for machine tools. Described is the theoretical background and knowledge. Presented is a custom design forming apparatus as well as the results of experimental tests which were carried out with them. W artykule przedstawiono proces niekonwencjonalnego formowania wgłębnego z użyciem obrabiarek. Opisano podstawy teoretyczne procesu i podstawy teoretyczne z tego zakresu. Zaprezentowano aparaturę zaprojektowaną w sposób dedykowany dla tego procesu jak też rezultaty prowadzonych eksperymentalnych testów z jej użyciem. Key words: cavity forming, machine tool, unconventional methods Słowa kluczowe: formowanie wgłębne, obrabiarka, metody niekonwencjonalne Introduction. The very idea of using machine tools for metal forming operations is not new [1-3]. The former Soviet technical literature mentions and describes experimental work carried out on machine tools. Thus, it would not be good to a priori reject the advantages of using machine tools in metal forming. In the following, attention is focused on the theoretical knowledge on cavity creation in full bodies. We also present the design and describe experimental work carried out in relation to verification of cavity creation on machine tools in an unconventional manner using the p ublished forming tools [4-7]. Theoretical knowledge. Indenting is one of the basic operations of volume forming, by means of which cavities are are formed in the material - the so-called indentations. Indenting is divided into free and guided indenting. In free indenting the blank side surface (circumference) is free, unlike in guided indenting where the side surface is in a sleeve that prevents the material to move sideways. [8-12]. In free indenting, the starting material is deformed, the height h is reduced, the material is compacted, the outer diameter [...]

Unconventional forming of tube ends DOI:10.15199/24.2017.8.23

  Introduction. It is generally known that performing a specific task in mechanical technologies requiring a ma chine as a power source it may not be applicable that, e.g. in the field of forming, only a machine tool is exclusively suitable for the issue. In some cases, one can use machines from other areas. A viable option seems to be, in particular, the use of machine tools in forming [1-5]. This paper illustrates how an ordinary axial lathe can be utilised in tasks that are composed of multiple operations and actions, and these being successfully reduced by the machine tool of choice, while we are discussing a purely forming technology. The problem and its solution. The task was to weld bot toms to the tube ends in order to make the tubes contained (closed). This task consisted of the following operations: - cut metal sheet to the required size, - cut discs with the required diameter using a tool in the eccentric press, - draw the bottom shape in one tool stroke of the hydraulic press, - create a tube and bottom, stitch and weld it around its perimeter, clean the weld. Necessary forming tools included: cutting and drawing instruments, and fo[...]

Use of magnetic field in sheet metal shearing DOI:10.15199/24.2018.10.6

  Introduction. Unconventional ways in forming pro- cesses prove to be the steady path in solutions of practical problems of manufacturing process. The question remains, how long will we be able to talk about strict division of forming between conventional and unconventional. The line between both of them will surely disappear in time. At first glance, the less common methods show one fact, that unlike conventional methods, they are more dependent on physical findings. One of the possible ways of dividing of material by us- ing magnetic field (force) is described in the following text. I have dedicated a few years on the faculty of Mechani- cal Engineering University of Žilina to the application of magnetic field in forming processes, therefore I can suggest my previous articles [1, 2]. Shearing with magnetic field is mentioned by B. Dobro- v[...]

Contribution to the construction of the riveting tool and its verification under laboratory conditions DOI:10.15199/24.2019.8.9

  Introduction. Riveting is a non-demountable combination of two or more machine parts using a special connection part - a rivet. The rivet squeezes connected components so that the friction between them and heads of the rivet prevents their mutual displacement after completion. Rivets can be divided into solid and hollow, among other divisions, which are not interesting here. In the next part of this paper the attention is devoted to riveting with solid rivets with a round head in rivet tools [7]. Theoretical part. An important issue in creating highquality rivet joints is to determine the optimal length of a rivet shaft. If the rivet shaft is longer than necessary, the trailing head must be hammered with large number of beats, which worsens the quality of joint. The rivet length is determined by combining the material thickness and length of the shaft to produce the trailing head of a rivet. The formula for determining the[...]

 Strona 1