Untitled

Shchiptsov, Vladimir

doi:10.1023/a:1023932131668

Cited by 6 publications

(2 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The initial transformation temperature also depends on the state of the silica, as the temperature can be relatively low (up to 900 • C) for silicic acid but much higher (up to 1200 • C) for rock crystal. This is also influenced by the impurities contained in the quartzite [37,38].…”

Section: Introductionmentioning

confidence: 99%

X-ray Diffraction Phase Analysis of Changes in the Lattice of Pervouralsk Quartzite upon Heating

et al. 2022

View full text Add to dashboard Cite

At present, quartzite is widely used across many industries. The properties of quartzite significantly affect the technology used during the preparation of the raw materials as well as the technology used for manufacturing the final product, which may be intended for further operation at different temperatures. The purpose of the study was to create a scheme for the transformation of quartzite that would describe the changes in the parameters of its lattice parameter upon heating and would offer guidance regarding the drying technology and technology required to obtain tridymite. A Bruker D8 Advance diffractometer was used to study changes in the phase composition of quartzite at the temperatures of 200, 400, 600, 879, 1000, 1200, 1470, and 1550 °C. A detailed scheme of transformations of PKMVI-1 quartzite with a SiO2 content of at least 97.5% at normal pressure was proposed for crystalline modifications formed during its heating. As a result of this research, the changes in the parameters of the lattice parameter—such as the average interplanar distance davg, the volume of the unit cell Vavg, the density of the unit cell Davg, and the molecular weight Mavg—were established.

show abstract

Section: Introductionmentioning

confidence: 99%

X-ray Diffraction Phase Analysis of Changes in the Lattice of Pervouralsk Quartzite upon Heating

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Other results from the heating of the quartzite are due to the imperfection of the physical and mechanical methods of research at the time. The X-ray crystallography method, introduced in the 1960s, revealed that during heating, cristobalite appears first and tridymite follows [39][40][41][42][43][44][45][46].…”

mentioning

confidence: 99%

Influence of Temperature Regimes of Synthetic Iron Smelting on Casting Production Efficiency

Trunova

Кукарцев

Tynchenko

et al. 2023

Metals

View full text Add to dashboard Cite

The purpose of the foundry is to provide the consumer with blanks for general machine-building (special) purposes which are as close as possible to the size of the future part in full compliance with the requirements. The competitiveness of these products is primarily dependent on the use of efficient and reliable smelting equipment which meets the necessary cost. The replacement of high-value ironworks and ironworks iron with steel scrap using induction melting furnaces (ICFs) reduces the cost of producing synthetic cast iron. However, this results in temperatures greater than 1500 °C, reduced lining stability and increased downtime of the smelter. As a result of the research carried out, a technology for the use of quartzite is proposed. Thereby, the purpose of this work is to establish temperature regimes for the smelting of synthetic pig iron, allowing the use in metal filling up to 70–90% of steel scrap; this leads to a reduction in the cost of purchasing bulk materials (depending on the brand of cast iron) up to 50% and, thus, increases the efficiency of synthetic cast iron smelting and castings production in general. After removal of the original moisture and the subsequent sintering of the manufactured lining, it provides the possibility of melting using the melting temperatures 1550–1600 °C. It increases the efficiency of the operation of the melting furnaces and eliminates the consumption of the ironworks and the melting of the cast iron in the blast furnace, as well as the cost of the lost alloy. As a result, metallurgical production will be able to reduce the volume of production and supply of cast iron for ironworks, which will improve their environmental situation during the production and processing of necessary raw materials.

show abstract

Development of a lining made from Karelian quartzites for crucible induction furnaces

Zavertkin

2009

Refract Ind Ceram

View full text Add to dashboard Cite

Factors are considered that increase the service life of a lining for a crucible induction furnace. Results are provided for laboratory studies and industrial tests of Karelian quartzites of Jotnian age of the Shokshinsk formation and Jatulian age of the Metchang'yarvinsk formation. The effect of impurities is quartzites on crucible induction furnace lining wear resistance is studied. Brief characteristics of quartzites are provided. The possibility is established of using waste materials from quarry production of Shokshinsk quartzites for preparing quartzite mixes.Keywords: Karelian and Swedish quartzites, lining mix, induction furnace, binding and sintering addition, boric acid.Crucible melting of cast iron, steel and non-ferrous metals relates to the main requirements of casting-metallurgical technology and also exhibits economic advantages over cupola melting of cast iron, and it has a cheap and rapidly replaceable acid lining. The economics of operating melting furnaces and the quality of melted metal depend on the quality and service life of the lining. Specifications laid down for lining materials relate to refractories based on quartzite. A quartzite lining is favorably distinguished from magnesite and alumina materials by cheapness and the fact that shrinkage is balanced by growth of quartz during allotropic transformations.Domestically produced furnaces for melting cast iron, steel and alloys based on copper mainly operate on a quartz lining. This lining is also most widespread abroad. For example, in Germany about 90% of induction furnaces use it. Quartzites that during quartz inversion retain adequate strength and density are suitable for lining induction furnaces [1].In crucible induction furnaces (Fig. 1) metal has a thermal, chemical, and erosion effect on the lining. High metaland slag-resistance of the lining is provided by minimum porosity of the sintered layer of the lining, for example of the Swedish lining mix Radanit (Fig. 2). An acid lining of a quartz mix has a constant volume or little growth within the limits of 1% during service. Between the sintered part of the lining and the inductor during crucible firing and its operation a lightly-sintered (buffer) layer is created that prevents the spread of cracks deeper into the lining towards the inductor. Lining expansion gives rise to slow sintering of the rammed walls of the crucible due to which a powder buffer layer is retained for a long time. The safety of operating a furnace with an acid lining is provided by the fact that the buffer layer prevents breakthrough of molten metal to the inductor. An acid lining is quite inert with respect to molten cast iron and slag, and it exhibits the required refractoriness.

show abstract

Untitled

Cited by 6 publications

References 3 publications

X-ray Diffraction Phase Analysis of Changes in the Lattice of Pervouralsk Quartzite upon Heating

X-ray Diffraction Phase Analysis of Changes in the Lattice of Pervouralsk Quartzite upon Heating

Influence of Temperature Regimes of Synthetic Iron Smelting on Casting Production Efficiency

Development of a lining made from Karelian quartzites for crucible induction furnaces

Contact Info

Product

Resources

About