Wyniki wyszukiwania - BazTech

1

Influence of the Trochoidal Tool Path Generation Method on the Milling Process Efficiency

Waszczuk Kamil

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 3

199--203

EN

The article presents a comparison of three trochoidal paths: written by G-Code, generated using the overlays from the machine level, and generated using the CAD/CAM environment. The parameters determining the effectiveness of the process were: maximum achievable feed speed, surface roughness and waviness, cutting forces and cutting temperature when milling NC6 steel (50HRC) using a 10 mm cutter dimeter. The main measurement results include: an increase in the maximum feed speed value by almost 35% when using the A and C paths compared to the type B path and nearly a double increase in surface roughness when using the path generated using the CAD/CAM environment compared to the B path. The most important conclusions was that it is not always possible to machine with the recommended parameters by the tool manufacturer, especially when machining narrow grooves. It was proven that that the use of paths with the displacement described by arcs and straight lines as a trochoidal step over reduces the possibility of milling at high feed rate.

2

Influence of the Trochoidal Tool Path on Quality Surface of Groove Walls

Waszczuk Kamil, Skowronek Hubert, Karolczak Paweł, Kowalski Maciej, Kołodziej Marek

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 3

38--42

EN

The article presents the results of machining materials in hardened state. In the paper, different trochoidal tool paths are compared with each other and with the conventional milling. The results of measurements show the relationship between tool path, roughness and waviness of grooves wall. The paper also presents pictures of grooves which were made. These results provide comparative material useful in the choice of the best milling strategy to the cutting process.

3

Influence of the path type on selected technological effects in the trochoidal milling

Waszczuk K., Karolczak P., Wiśniewska M., Kowalski M.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 1

147--153

EN

The article presents basic information about machining materials in hardened state – it particularly describes a method of the so called hard milling. The paper discusses strategies and methods in hard milling, presents trochoidal milling, its advantages and disadvantages. It also presents research methodology and effects which concerned determination of a tool path impact on selected technological effects after trochoidal milling of the groove.

4

Advanced open CNC system with in process tool path compensation

Hascoet J.-Y., Rauch M.

Journal of Machine Engineering

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2014

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Vol. 14, No. 3

48--57

EN

Despite several technical advances over the last decade, CNC controlled manufacturing still bases upon outdated paradigms: manufacturing data are generated and transferred along a heterogeneous and divided CAD/CAM/CNC data chain. The role of the NC controller is limited to the execution of tool paths generated beforehand and the possibility of online tool path adaptation is not planned in legacy NC controllers. In contrast, practical observations make this legacy approach quite inappropriate in an industrial framework. Significant geometrical variability is sometimes observed both prior and after milling in parts that belong to the same batch. In that context, the integration of online tool path adaptation strategies appears to be essential. In this paper, a methodology for correcting the tool path in real-time thanks to measurements provided by a laser scanner moving with the tool is introduced. The resulting local information is used to approximate the workpiece exact geometry by using a POD (Prosper Orthogonal Decomposition) snapshot technique and to adjust the path in accordance. This method has the great advantage of taking into consideration geometrical features such as curvature, twist but also additional parameters whose impact on the tool path is significant (unexpected initial setup of the part for example). This method has been implemented on the advanced CNC programming platform of the laboratory, which hosts in particular a high speed machining centre equipped with an open NC controller.

5

Numerical simulation of modified friction Stir Spot Welding

Buffa G., Fratini L.

Computer Methods in Materials Science

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2009

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Vol. 9, No. 1

117-122

EN

Spot welding can be considered a very common joining technique in automotive and generally in transportation industries as it permits to obtain effective lap-joints with short process times and what is more it is easily developed through robots and automated systems. Recently the Friction Stir Spot Welding (FSSW) process has been proposed as a natural evolution of the already known Friction Stir Welding (FSW) process, allowing to obtain sound spot joints that do not suffer from the insurgence of typical welding defects due to the fusion of the base material. In the paper, a variation of the Friction Stir Spot Welding (FSSW) process has been considered. In detail, different peculiar tool paths are given to the tool, after the sinking phase, nearby the initial penetration site, with the aim to enhance the final joint mechanical properties. A continuum based FEM model for Friction Stir Spot Welding process is proposed, that is 3D Lagrangian implicit, coupled, rigid-viscoplastic. This model is used to investigate the distribution of temperature, strain and strain rate in the heat affected zone and the weld nugget. In particular, the large values and gradients of temperature and strain rate found in the weld zone during the process can be used to determine the Zener-Holomon parameter which, in turn, strongly affects the Continuous Dynamic Recrystallization (CDRX) process that takes place in the weld nugget. In this way, the average grain size and the extension of the nugget can be predicted with the ultimate goal to get information on the joint mechanical resistance. The developed model appears an effective tool in order to design effective spot joints

PL

Proces spawania punktowego jest często wykorzystywanym sposobem łączenia elementów w przemyśle transportowym a w szczególności w przemyśle samochodowym. Podstawową zaletą tej metody jest możliwość uzyskania połączenia zakładkowego w krótkim czasie z wykorzystaniem zautomatyzowanych systemów robotów przemysłowych. Obecnie bardzo dynamicznie rozwija się proces spawania metodą punktowego zgrzewania tarciowego z mieszaniem materiału zgrzeiny (Friction Stir Spot Welding FSSW). Metoda ta jest udoskonaleniem metody Friction Stir Welding (FSW). Uzyskane w ten sposób spawy charakteryzują się lepszymi własnościami niż spawy uzyskane metodą konwencjonalną. Celem niniejszej pracy jest szczegółowa analiza procesu FSSW aby podnieść własności uzyskanego połączenia. Badania skupią się m.in. na badaniu wpływu trajektorii ruchu narzędzia. Opracowany model numeryczny oparty jest o metodę elementów skończonych z jawnym sztywno - lepkoplastycznym modelem. W trakcie pracy analizowano rozkłady temperatury, odkształceń, prędkości odkształcenia w obszarze jądra zgrzeiny oraz otaczającego materiału. Analiza w/w rozkładów dostarczyła istotnych informacji na temat końcowych własności spoiny oraz potwierdziła możliwość wykorzystania symulacji numerycznej do opracowania nowych technologii spawania.