Wyniki wyszukiwania - BazTech

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Zastosowanie nowoczesnej metodyki badań w procesie optymalizacji konstrukcji wielkogabarytowych odlewów

Turzyński J., Pytel A., Pysz S., Żuczek R.

Przegląd Odlewnictwa

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2016

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Vol. 66, nr 1-2

10--14

PL

Przedstawiono metodykę oraz narzędzia wspomagające proces badania i projektowania ciężkich gabarytowych odlewów, na przykładzie odlewanej metalurgicznej kadzi rozlewniczej o masie Q=18t. Zastosowanie kamery termowizyjnej pozwoliło precyzyjnie określić dynamiczną mapę rozkładu temperatury całego cyklu technologicznego pracy kadzi rozlewniczej. W celu określenia wad wewnętrznych oraz geometrii odlewu kadzi zastosowano nieniszczące metody badania. Na podstawie wyników badań właściwości mechanicznych i fizycznych, zakresu temperatury pracy kadzi odlewniczej oraz innych realnych parametrów opracowano przestrzenny model, który poddano komputerowej symulacji zjawisk zachodzących podczas pracy kadzi. Otrzymane wyniki zostaną wykorzystane do projektowania optymalnej konstrukcji kadzi.

EN

The methods and tools aiding the process of designing and testing of the heavy castings of large overall dimensions, basing on the example of a cast metallurgical ladle of the total weight Q=18t, were described. The use of thermovision camera enabled making a very exact map of the dynamic temperature distribution during the entire ladle operating cycle. To determine the presence of internal defects and the cast ladle geometry, a non-destructive testing technique was applied. The results of the mechanical tests and examinations of the physical properties, along with determination of the ladle operating temperature range and of other operating parameters were used to design a 3D model, which next served in computer simulation of the phenomena taking place during the ladle operation. The obtained results helped in preparing an optimum design of the ladle

2

Synergy of practical knowledge of molding sands reclamation in heavy casting foundry of iron alloys

Ignaszak Z., Prunier J. B.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3

30--36

EN

The paper summarizes research realized by the author in laboratory and industrial conditions (foundries of cast steel and cast iron, castings up to 50 tons) on the effects of the chemically hardened molding sands regeneration using hard/soft rubbing in the dry reclamation. A reference was simultaneously made to advisability of application of the thermal regeneration in conditions, where chromite amount in the circulating (reclaimed) molding sand goes as high as above ten percent. An advisability of connecting standard and specialized methods of examination of the reclaimed sands and molding sands made using it was pointed out. A way of application of studies with the Hot Distortion Plus® method modified by the author for validation of modeling of the thermo-dynamic phenomena in the mold was shown.

3

Influence of compound deoxidation of steel with Al, Zr, rare earth metals, and Ti on properties of heavy castings

Senberger J., Cech J., Zadera A.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 1

99-104

EN

Heavy steel castings deoxidized with aluminium are sometimes brittle intercrystalline failed during their service along primary grain boundaries what is initiated by aluminium nitrides and so called conchoidal fractures are formed. The tendency to forming the conchoidal fractures depends in particular on cooling rate (the casting modulus), aluminium and nitrogen contents in steel. During deoxidation, when manufacturing heavy castings, the elements with high affinity to nitrogen, zirconium or titanium, are added to steel that would decrease nitrogen activity by the bond on stable nitrides. The formation of stable nitrides should reduce the tendency of steel to the formation of conchoidal fractures. Deoxidation was thermodynamically analyzed at presence of the mentioned elements. For particular conditions a probable course of deoxidation was estimated at test castings. The deoxidation course was checked by microanalysis of deoxidation products (inclusions). For service and experimental castings the anticipated composition of inclusions was compared. It has been proved that in heavy castings with high aluminium contents in steel under studied conditions neither the addition of zirconium nor of titanium nor of rare earth metals will prevent the formation of conchoidal fractures.

4

Increase of liquid metal utilization during production of bearing circle castings for cement furnaces

Zadera A., Senberger J., Carbol Z., Pluhaček J.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2

111-116

EN

In manufacture of super heavy castings for cement furnaces a saving of liquid metal has been achieved by lowering the riser weight. By solidification modelling with the aid of the Niyama criterion a zone in the riser was designated where the occurrence of foundry defects (shrinkage porosity) can be expected. A plate of the material of dimensions ca 700*800*250 mm was taken from the riser. After thermal treatment the samples for making the bars for the static tensile test were taken from it. Based on done tests it has been found out that mechanical characteristics obtained from the static tensile test correlate, besides contraction, in the chosen level of statistical importance of p = 0.01 with carbon content. Neither in the zone of probable occurrence of defects designated by the Niyama criterion during solidification modelling the drop of strength characteristics was observed. Carbon content in a decisive extent influenced the strength characteristics. In case of ductility and contraction the convenient correlations with carbon content were observed from the riser height of 200 mm only. In the height of 400 mm there was already considerable variation of values and some values were lower ones than is demanded by standards.