Refractories Factory Research Articles

Investigation on mechanical and tribological properties of magnesite reinforced aluminium 6061 composites

During the sintering process in the shaft kiln of refractory factories, a considerable quantity of materials is separated and dumped as Waste Magnesite (WM). The other superior grades, Lightly-Calcined Magnesite (LCM) and Dead-Burned Magnesite (DBM), are separated at different temperatures from the shaft kiln. The WM materials still have 8% of magnesium with some sand and dust particles in huge ranges. These materials are primarily used in the applications of medicine and fertilizers and animal feed processing and additives. This work investigates the potential of WM particles as reinforcement materials in the Al 6061 alloy matrix. In order to compare the characteristics of WM-based composite, LCM and DBM powders were also considered as reinforcement particles. The WM, LCM, and DBM particles were mixed with a 15% weight ratio to Al 6061 alloy, and composites were fabricated using the Stir Casting method. The surface morphology investigations through Scanning Electron Microscopy (SEM) revealed that these particles were well distributed and dispersed within the alloy matrix and with good interfacial adhesion. It is noted that Al 6061/15% wt. LCM composite possesses a better tensile strength than Al 6061/15% wt. WM and Al 6061/15% wt.DBM composites. The impact value produced by the WM-based composite is better than the LCM and DBM composites. The Wear Rate and Coefficient of Friction (COF) were examined through a Pin-on-Disc apparatus. Al 6061/15% wt. WM composite tested a low wear rate (9.74 × 10−6 mm3 m)−1. The results show that Al 6061/15% wt. LCM composite achieved the least COF value of 0.681 at an applied load of 0.5 Kg and a sliding distance of 2826 m. The results prove that the wastage magnesite is good enough and the most robust reinforcement material for Aluminum 6061 alloy-based composite.

Charon's refractory factory.

We combine novel laboratory experiments and exospheric modeling to reveal that “dynamic” Ly-α photolysis of Plutonian methane generates a photolytic refractory distribution on Charon that increases with latitude, consistent with poleward darkening observed in the New Horizons images. The flux ratio of the condensing methane to the interplanetary medium Ly-α photons, φ, controls the distribution and composition of Charon’s photoproducts. Mid-latitude regions are likely to host complex refractories emerging from low-φ photolysis, while high-φ photolysis at the polar zones primarily generate ethane. However, ethane being colorless does not contribute to the reddish polar hue. Solar wind radiolysis of Ly-α–cooked polar frost past spring sunrise may synthesize increasingly complex, redder refractories responsible for the unique albedo on this enigmatic moon.

Gamma spectrometric characterization of refractory products used in Turkey

This is the first detailed study related to the radiometric characterization of refractory materials produced for use in the industries of iron–steel, cement and glass manufacturing in Turkey. In this study, the activity concentrations of 226Ra, 232Th and 40K naturally occurring in 52 refractory material samples collected from Turkey's leading refractory factories were measured by using a gamma spectrometer with HPGe detector. Results show that the natural radioactivity of refractory material samples varies depending on raw material. The values of the activity concentrations of 226Ra, 232Th and 40K measured in the refractory brick and concrete samples varied from 1.3 to 384.2Bqkg−1 (average: 173.5±20.2Bqkg−1), 2.9 to 392.9Bqkg−1 (average: 176.7±20.8Bqkg−1) and 18.9 to 679.6Bqkg−1 (average: 130.4±23.9Bqkg−1) and 24.0 to 158.2Bqkg−1 (average: 73.3±10.5Bqkg−1), 25.0 to 134.4Bqkg−1 (average: 76.3±10.8Bqkg−1) and 31.0 to 480.0Bqkg−1 (average: 172.8±40.5Bqkg−1), respectively. The activity concentrations of 226Ra and 232Th measured in fireclay brick and high alumina brick samples are significantly higher than the average values of earth's crust.

북한 광물자원 부존 및 개발현황 개요

북한의 광물자원 부존량 및 생산 현황을 종합하면, 북한에서 부존규모가 큰 주요 광물종은 마그네사이트, 석회석, 석탄(무연탄), 인상흑연, 철, 금, 은, 연, 아연 등으로 판단된다. 기타 동, 몰리브덴, 중석, 인광석 등이 잠재성이 큰 광물자원으로 평가된다. 북한의 광물자원 수출 대상국은 중국으로서 주요 수출 광물로는 무연탄, 철광석이 75%로서 압도적으로 우세하다. 수출국은 중국 외 EU국가이나, 중국 수출이 70%에 달한다. 북한은 금 매장량 약 2,000톤과 연간 생산량은 약 2 톤(금속기준)이며, 대표적 광산은 수안, 홀동, 대유동광산이며, 6개 금 제련소가 운영 중이다. 철 매장량은 Fe 63.5% 기준으로 약 43억 톤, 연간 생산량은 약 5백만 톤, 주요 철광산은 무산, 리원, 북청, 은율, 신원, 재령광산이며, 7개 제철소 및 제강소가 운영 중이다. 연-아연 매장량은 금속 기준으로 연이 약 4.7백만 톤, 아연이 15백만 톤, 연간 생산량은 금속 기준 연이 약 26,000 톤, 아연이 금속 기준 50,000 톤이다. 주요 연-아연 광산은 검덕, 은파, 성천광산이며, 6개 제련소가 운영 중이다. 마그네사이트 매장량은 MgO 95% 기준으로 약 28억 톤, 최근 연간 생산량이 정광 기준 150,000 톤, 주요 광산은 룡양, 대흥, 쌍룡광산이며, 5개 마그네슘 내화물공장이 가행중이다. 인회석 매장량은 <TEX>$P_2O_5$</TEX> 30% 기준으로 약 3.4억 톤, 최근 연간 생산량은 원광석 기준 약 300,000 톤, 주요 광산은 대대리, 동암, 풍년광산이다. 석탄은 북한에서 중요한 전략 연료광물자원으로 인식되고 있으며, 주 에너지원이다. 석탄 매장량은 186억 톤, 연간 생산량은 2천만 톤이다. 주요 석탄광산은 평남에 집중되고 있으며, 직동광산이 북한에서 가장 큰 석탄광산이다. The potential mineral resources in North Korea are magnesite, limestone, coal, graphite, iron, gold, silver, lead, and zinc. North Korea is mainly exporting coal and iron to China(70%) and EU countries. Gold ore reserves(or resources) in North Korea are about 2,000 tons and annual production is 2 tons based on metal. Major gold mines are Sooan, Holdong, and Daeyoodong mines and six smelters are operating. Fe ore reserves (or resources) are 4.3 billion tons and annual production is about 5 million tons based on 63.5% Fe. Major iron mines are Moosan, Leewon, Eunryul, Shinwon, and Jaeryong and 7 smelters are operating. Pb and Zn ore reserves(or resources) are Pb 470,000 tons and Zn 15 million tons, and annual productions are about Pb 26,000 tons and Zn 50,000 tons based on metal respectively. Major Pb-Zn mines are Gumdock and Seongcheon mines. Magnesite ore reserves(or resources) are 2.8 billion tons (95% MgO) and annual production is about 150,000 tons. Major magnesite mines are Ryongyang, Daeheung Youth and Ssangryong mines, and 5 magnesium refractory factories are operating. Apatite ore reserves(or resources) are 340 million tons(30% <TEX>$P_2O_5$</TEX>) and annual production is about 300,000 tons(crude ore). Major apatite mines are Daedaeri, Dongam and Poongnyen mines. Coal is established as an important strategic fuel mineral resources and is a major energy source in North Korea. Coal ore reserves(or resources) are 18.6 billion tons and annual production is about 20 million tons. The main coal fields is located in southern Pyongan and the Jigdong mine is the biggest in North Korea.

Production of refractory concretes and practice in using them in glass-melting aggregates

The refractory concrete items and refractory pastes used in glass-melting aggregates manufactured by Semiluki Refractory Factory are presented. Their specifications are reported—strength, density, porosity, etc.

Production parameters for ceramics based on waste at the Zaporozhe Refractories Factory

The Zaporozhe Refractories Factory carried out a study to develop technical parameters for making ceramics on the basis of blast-furnace slag, Orekhovsk sand, Polozhe clay, and production waste. Plans were worked out to build a section for making ceramic brick with an output of 10 million items a year.

Refractory channel composition based on production waste from silicon carbide articles

The possibility and desirability of using wastes from the production of silicon carbide articles from the Zaporozhe refractory material factory as a filler mixture for ramming the channels of blast furnaces instead of scarce coke fines which are the main component of channel mixtures used in the Zaporozhstal' Combine is demonstrated.

Introducing separate beneficiation technology for magnesites at the Magnezit Combine

The Magnezit Combine has completed measures to increase the throughput of existing ducts supplying the starting materials to the beneficiation section; installed a self-balancing, two-screen sieve unit GST-62A (heavy type) instead of the single screen unit; and put into operation a second conical separator SK-3.6 in the section that handles ore 70-8 mm in size; this has led to the use of a procedure for the separate beneficiation of magnesites in narrow fractions 70-40 (25) and 40 (25)-8 mm, and brought about improvements in the quality of the concentrate, as well as increasing the output of the beneficiation section by 30%. When the technology was being developed using ordinary ores containing 4–6% CaO and contaminated with less than 15% dolomite we obtained up to 75% (of the original) of overall high-grade magnesite concentrate of coarse and fine fractions grade MIO (TU-14-200-350-89) with 1.07–1.35% CaO and 0.78–0.8% SiO2 in place of the MI concentrate using the combined beneficiation method. As a result of the development of the optimum schedules in heavy suspensions and preliminary separation of the starting ore into narrow fractions on a screen with 25 mm apertures, we established the possibility of processing balanced and nonstandard ores from special dumps containing more than 7% CaO and dolomite impurities of more than 18–20%, with the production from coarse fraction of 70-25 mm magnesite of up to 30% high-quality magnesite concentrate MIO, and from fine fraction 25-8 mm — a concentrate of MI quality. These concentrates are suitable for making bricks and powders used in refractory factories of the country on a level with those from ordinary ores, which is especially important where there is a scarcity of raw materials at the combine. The technology described above should improve the quality of magnesite concentrate. The savings from using it for reprocessing nonstandard raw materials tranported from special dumps was 128,8000 rubles a year.

Dry periclase body for lining inductors of channel furnaces

Laboratory and technological investigations were made to select dry periclase bodies for lining induction channel units. The trial batches prepared at the Experimental Factory of the Ukrainian Institute of Refractories and Nikitov Dolomite Factory during service in the lining of induction channel furnace ACEA and a 30-ton Piks furnace, and also in the inductors of pouring devices showed positive results. The body is supplied ready for use, does not require moistening before making the lining, substantially reduces the lining-work time (1 h instead of 10–14 h with the moistened body), and makes the removal of the spent lining easier.

Study of the suitability of clay slates of the Panteleimonov deposits for use in ceramic brick manufacture

Laboratory investigations and factory experiments established the suitability of clay slates from the Panteleimonov deposits for the production of high-grade ceramic brick by dry pressing. On the basis of data obtained we developed and delivered to the Panteleimonov Refractories Factory a proposal for the design of a production line and technical process for making brick by the dry method based on clay slates of the Panteleimonov deposits.

Periclase articles based on Korean magnesite powder

Laboratory and technological development with the production of industrial batches at the Panteleimonovsk refractories factory and the Chasov Yar Combine established that by using Korean magnesite powder it is possible to make periclase articles meeting the demands of GOST 4689-74.

Increasing the apparent density of cast baddeleyite-corundum products for making optical glass

In order to facilitate the production of optical glass, the Podolsk Refractories Factory is manufacturing products corresponding to the BKCh-33 and BKCh-34 grades and having an apparent density not less than 3.4 and 3.6 g/cm 3, respectively [3]. The experience gained during the service of these products showed that the formation of striae* (spills) and bubbles becomes very intense when the central porous zone (cavity) of the beam comes into contact with the glass mass. This zone is characterized by a high concentration of a glassy phase, pores~ and gas liberating impurities.

Periclase-carbon products for electric steel-melting furnaces

Periclase-carbon articles made of sintered periclase powders, prepared with the use of the “press-packet” technolotical schedule, have a very low gas permeability and a rather high magnetic susceptibility. The use of periclase-carbon articles facilitated an increase in the resistance of the walls of 100-ton electric steel-melting furnaces with water-cooled panels by 1.8–2.5 times compared with the life of walls made from fired periclase-chromite articles. The nature of the wear of periclase-carbon products is due to their slag destruction and the reduction in the magnetic susceptibility. The cemented blocks of periclase-carbon articles using periclase-iron mortar in the walls of 100-ton electric steel-melting furnaces had the same wear resistance as for separate periclase-carbon bricks. It is desirable to continue testing periclase-carbon bricks made from sintered periclase powders in order to determine the most rational regions of application, and their introduction into production in refractory factories.

Obtaining high-alumina cement at the semiluksk refractories factory

We demonstrate that it is, in principle, possible to obtain refractory high-alumina cement on industrial equipment at the Semiluksk refractories factory. Technological parameters were developed for preparing raw mixtures, pressing the green articles and firing in a tunnel kiln. It was established that the mass percentage of SiO2 in the raw mixture should not exceed 1.5%. For industrial production of high-alumina cement in department No. 1 it is necessary to implement measures on the mechanization of the production process.

Temperature field in the setting of mullite corundum products in a tunnel kiln

Investigations of the temperature field of the setting in a tunnel kiln of the high-alumina products section of the Zaporozhe Refractories Factory revealed individual features of the firing cycle for mullite-corundum articles; the low temperature of the setting in the first heated positions of the firing zone (Nos. 24–26) working without automatic regulation of the gas consumption according to the prescribed temperature of the kiln; the irregularity of the temperature field over the height and width of the setting; the variability of the linear dimensions and quality factors of the finished goods over the setting volume. Certain measures were worked out and used to eliminate these drawbacks.

Mullite corundum refractories for out-furnace working and continuous casting of steel

The Zaporozhe refractories factory has set up the industrial manufacture of mullite-corundum tubes using a technology developed by the Ukrainian Institute of Refractories together with the factory. The tubes are designed for continuous casting of steel and blowing it in the ladle at the Azovstal' Factory. Following improvements in the production method and increases in the resistance of the goods, it was possible to reduce the specific consumptions, and this gave a saving annually of 88,600 rubles.

Stabilizing quartz slip in the production of immersion sheaths

A technology was developed for stabilizing quartz slip for making immersion sheaths at the Podolsk refractories factory using electrolytes, enabling us to reduce the slip preparation time by 19–22 h, reducing its viscosity with a reduction in the water content from 22 to 17–20%, reducing the loss of greenware. In the conditions of KTs-2 of the Novolipetsk plant, the experimental nozzles showed a resistance similar to that of nozzles obtained by the traditional method used at Podolsk.

Experience with making high-alumina cement at the Semiluksk Refractories Factory

It was shown to be possible to make low-iron high-alumina cement based on the waste products from the production of corundum insulating bricks or finely milled alumina.

Producing mullite-corundum refractories at the zaporozhe refractories factory

The Zaporozhe Refractories Factory has introduced a method for making mullite—corundum articles from alumina and Polozhe kaolin. The technology was developed by the Ukrainian Scientific-Research Institute of Refractories together with workers from the factory. We have mastered the mass production of articles for building the walls of stoves and hot-blast air ducts. The articles meet the requirements of GOST 2090175.bl

Guniting of the lining of steel-teeming ladles at the Krivorozhstal' Factory

The No. 2 converter shop and the open-hearth shop at the Krivorozhstal' Factory have adopted guniting of the linings of the 150-ton and 330-ton steel-teeming ladles. The Krasnogorov Refractory Factory has begun the manufacture of chamotte-clay guniting powders. The mean life of the lining of a 330-ton ladle has been enhanced by 3–4 meltings as a result of guniting, that of a 150-ton ladle by 5–6 meltings. The consumption of ladle brick in No. 2 converter shop has been reduced from 6.85 to 4.60 kg/ton of steel, and in the open-hearth shop from 5.65 to 4.5 kg/ton of steel. The adoption of guniting saved 200,000 rubles in 1976.