Wyniki wyszukiwania - Biblioteka Nauki

1

Dependence of Reoxidation Effect on a Type of Gating System in Investment Casting Technology

100%

Vrátný O. , Herman A.

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2018

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nr 3

2

Possibilities of Bifilm Amount Reduction in Al Castings by Gating System Design Optimization

100%

Brůna M. , Galčík M. , Sládek A. , Martinec D.

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tom Vol. 66, iss. 2

549--559

EN

Submitted work deals with the possibilities of reducing reoxidation by improved gating system design. The result of the reoxidation is the of furled oxide layers - bifilms. During experimental works, non-pressurized and naturally pressurized gating systems designs were introduced and evaluated. Mechanical properties, fracture area, hot tearing index, bifilm index and EDX analysis were used during evaluation. Paper aim is also to clarify the reoxidation phenomenon by visualization with the aid of ProCAST numerical simulation software. Achieved results clearly confirmed the positive effect of the naturally pressurized gating system, main emphasis needs to focus on finding the proper way to reduce the melt velocity. By using vortex element extension at the end of the runner was achieved positive results in term of reoxidation suppression.

3

Simulation and Casting Process of Aluminum Alloy Multi-Way Valve Body with Various Gating Systems

86%

Li R. , Chenb L. , Su M. , Zeng Q. , Liu Y. , Wang H.

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4

Possibilities of Bifilm Amount Reduction in Al Castings by Gating System Design Optimization

86%

Brůna M. , Galčík M. , Sládek A. , Martinec D. , Brůna M. , Galčík M. , Sládek A. , Martinec D.

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nr 2

5

Impact of Sprue Base in Gating System on Quality of Filling – the Compromise Between Theory and Practice

86%

Siodmok B. , Jezierski J. R. , Dorula J. , Romelczyk R.

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tom Vol. 18, iss. 3

167--172

EN

Foundry technologists use their own style of gating system designing. Most of their patterns are caused by experience. The designs differ from plant to plant and give better or worse results. This shows that the theory of gating systems is not brought into general use sufficiently and therefore not applied in practise very often. Hence, this paper describes the theory and practical development of one part of gating systems - sprue base for automated horizontal moulding lines used for iron castings. Different geometries of sprue bases with gating system and casting were drawn in Solid Edge ST9. The metal flow through the gating systems was then simulated with use of MAGMA Express 5.3.1.0, and the results were achieved. The quality of flow was considered in a few categories: splashes, air entrapment, vortex generation and air contact. The economical aspect (weight of runner) was also taken under consideration. After quantitative evaluation, the best shape was chosen and optimised in other simulations with special attention on its impact on filling velocity and mould erosion. This design (a sprue base with notch placed in drag and cope) is recommended to be used in mass production iron foundries to reduce oxide creation in liquid metal and especially to still metal stream to improve filtration.

6

Plastic filling simulation comparison analysis of the gating system in injection moulding parameter

86%

Umor M. Z. , Mohd A. , Efendee A. M. , Khir M. , Bahiyah Baba N.

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tom Vol. 112, nr 2

64--69

EN

Purpose: The paper is discussed the anticipation of the simulation software precision with the real moulding process by setting up the distinctive metering stroke separation. Design/methodology/approach: The Inventor CAD software was used to design the product experiment and perform the simulation by applying MoldFlow application to produce the processing parameter defining for the injection moulding machines. Findings: The results predicted by this filling simulation appears reasonable result as compared to the injected product. Prediction analysis given by the software is exceptionally valuable for the injection moulding parameter setting machines which can diminish the time of mould setup and can reduce the trial stage on the production line. Research limitations/implications: The gating system is the most crucial part in injection moulding process and the limitation is to get the accurate filling time and injection pressure to ensure the cavity is fully filled before the material at the gate solidify. Originality/value: Gating system configurations are utilized to optimize the filling conditions of injection moulding parts. This important element was developed for achieving product quality. The utilize of simulation software is exceptionally supportive in the model designing stage to predict the quality and process capacity for the product. This paper presents the filling simulation of the side gate system to the injection moulding parameter.

7

Wyznaczanie minimalnej grubości wlewu doprowadzającego

72%

Borowiecki B.

Archiwum Odlewnictwa

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2006

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tom R. 6, nr 22

95-100

PL

Minimalna grubość wlewu doprowadzającego powinna być większa od trzech grubości warstwy przyściennej metalu, która zależy z kolei od łącznej grubości warstw: reologicznej i krzepnącej. Zastępczy parametr reologiczny można oznaczyć na podstawie prób lejności. Uwzględniając zastępczy parametr reologiczny i ciśnienie metalostatyczne (położenie przekroju wlewu) można określić grubość reologicznej warstwy przyściennej na przekroju danego wlewu doprowadzającego. Grubość krzepnącej warstwy przyściennej oblicza się uwzględniając czas zalewania i stałą krzepnięcia wyznaczoną z zastosowanego wzoru Chvorinova.

EN

The minimum thickness of runner in gating system depends on boundary layers: rheological and solidifying. The rheological boundary layer thickness of metal has been calculated on the basis of rheological parameters defined in fluidity test. The solidifying boundary layer thickness of metal after determination of solidifying constant and flow time has been calculated.

8

Casting Quality Improvement by Gating System Optimization

72%

Bruna M. , Galčík M.

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2021

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tom Vol. 21, iss. 1

132--136

EN

One of the main reason for decreased internal homogeneity of aluminium alloy castings is reoxidation. The resulting products of reoxidation are doubled oxides, so called "bifilms". Submitted paper deals with optimization of gating system design in order to reduce reoxidation processes taking place in mold cavity. Experimental work compares and evaluates three gating systems designs based on non-pressurized and naturally pressurized principles. Unconventional spin trap extension of runner was used in third design. Among the evaluated aspects were: mechanical properties, hot tearing index, visual inspection of average porosity amount, numerical simulation of velocity, turbulence and oxide amount. Paper aim is also to clarify the reoxidation phenomenon by visualization with the aid of ProCAST numerical simulation software. Results of mechanical properties and hot tear index clearly confirmed the positive effect of the naturally pressurized gating system with applied element for velocity reduction.

9

Influence of Overflow Connecting Channel Cross-Section Design on Selected Parameters of High Pressure Die Casting

58%

Majernik J. , Podařil M. , Gojdan D.

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2021

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tom Vol. 21, iss. 2

75--80

EN

High pressure die casting technology (HPDC) is a method enabling the production of shape-complex casts with good mechanical properties, with high repeatability of production within narrow tolerance limits. However, the casts show, to some extent, basic porosity, which may reduce their mechanical and qualitative properties. One of the main areas to focus on in order to reduce the porosity of casts is the correct design and structure of the gating and overflow system. Submitted article is devoted to the assessment of the connecting channel cross-section design for connecting the overflows to the cast on selected parameters of the casting process. Five different cross-section designs of connecting channels are considered, enabling the removal of gases and vapors from the volume during the molding. The connecting channels are designed with a constant width g = 10mm and variable height h1 =1.50 mm, h2 = 1.25 mm, h3 = 1.00 mm, h4 = 0.75 mm and h5 = 0.6 mm. The primary monitored parameter is the gas entrapment in selected points of the cast. The following is an evaluation of the pressure conditions change in the mold cavity at the end of the filling mode and local overheating of the mold material just below the surface of the mold face. With regard to the monitored parameters, based on the performed analyzes, the most suitable design solution of the connecting channel is assessed and recommendations for the design and structure of the overflows and their connection to the cast are derived.

10

Zastosowanie narzędzi CAx w projektowaniu form wtryskowych

58%

Ziobro J. , Marciniec A.

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2010

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tom T. 55, nr 11-12

877-862

PL

Artykuł ma charakter przekrojowy, omówiono w nim zastosowanie wzajemnie skorelowanych narzędzi CAx [wieloaspektowy termin opisujący zastosowanie ogółu technik inżynierskich i narzędzi komputerowego wspomagania: projektowania (CAD), analiz (CAE), wytwarzania (CAE), itp.]. Zasadniczą część procesu konstruowania wykonano w parametrycznym programie Inventor. Sprawdzenie poprawności działania formy prowadzono w programie MSC.MARC. Realizację zdolności wypełnienia gniazda formy realizowano w programie Mold-flow. Za pomocą tej aplikacji dokonano również oceny wpływu parametrów geometrycznych układu zasilania formy wtryskowej na ciśnienie i siłę zamknięcia. Ogół tych działań przeprowadzono z uwzględnieniem kryterium minimalizacji obciążenia formy. Biorąc pod uwagę wyniki analiz zbudowano ćwiartkowy model geometryczny formy w aplikacji Inventor. Zastosowana metoda analizy sprzężonej w programie MSC.MARC pozwoliła na dokonanie sprawdzenia formy pod względem występujących deformacji oraz związaną z tym możliwość rozszczelnienia układu. Wskazano źródła powstających wypływek oraz występujących niebezpieczeństw. Poprawność działania formy analizowano przede wszystkim pod względem możliwości zakleszczeń występujących w węźle słup-tuleja prowadząca. Na podstawie numerycznych analiz zaproponowano rozwiązanie konstrukcji węzła słup-tuleja, pozwalające na wyeliminowanie tego niepożądanego zjawiska. Wskazano również najbardziej korzystne pasowanie tego węzła oraz jego wymaganą czynną długość styku. Kompletny model geometryczny formy zbudowano w programie Inventor na podstawie modeli wynikających z przeprowadzonych badań symulacyjnych.

EN

In this review paper, the application of correlated CAx tools - a multi-aspect terminology used to describe the application of general engineering techniques as well as the computer aid tools for design (CAD), analysis (CAE), production (CAE) etc. has been presented. The fundamental part of the construction process was performed with the aid of the parametrical program Inventor. The verification of the functionality of the form was performed with the MSC.MARC program. The optimal mold-filling capabilities were determined in the Moldflow program. This program was also used to evaluate the influence of geometric parameters of the gating system of the mold on injection pressure and clamp force. Most of these studies were done with special consideration the criterion of minimizing the load of the mold. On the basis of the results of the performed analysis, a quarter of the geometric model of the mold was built using Inventor applications. The applied analysis method together with the MSC.MARC program allowed for the testing of the molds in terms of deformation and also permeability resulting from it. The potential sources of flashes and dangers were also indicated. The effectiveness of mold activity was analyzed taking into consideration, first and foremost, the possibility of jams occurring in the leader pin-guide bushing. On the basis of numerical analysis a construction solution for the leader pin-guide bushing has been proposed which would eliminate this most undesired phenomenon. The most suitable position as well as the required active contact length of this kinematic pair was shown. The complete geometric model of the mold was constructed according to Inventor program on the basis of the models obtained from the performed simulation studies.