Saxena A.,Steel Authority of India Ltd SAIL |
Kumar S.,Steel Authority of India Ltd SAIL |
Prakash K.,Steel Authority of India Ltd SAIL |
Datta R.,R and C Laboratory |
And 4 more authors.
Materials and Manufacturing Processes | Year: 2011
API X-70 grade plates and hot strips microalloyed with Nb, V, and Ti have been developed simultaneously from two units of SAIL at Bhilai and Bokaro Steel Plants, respectively. Suitably designed steel (C: 0.1% max., Mn: 1.7% max., Nb: 0.06% max., V: 0.04% max., and Ti: 0.02% max.) was processed through vacuum arc degassing (VAD), and cast into 240mm thick slabs and hot rolled into 20mm thick plates, deploying an appropriate thermomechanical controlled processing (TMCP) technology. The tensile properties (YS: 473-531MPa, YS/UTS: 0.74-0.88, %El: 32-48%) and Charpy impact toughness properties (CIE: 113-159J at 0°C) were found to be quite attractive, owing to their fine microstructure of ferrite (∼10m) and low pearlite (volume fraction of ∼12%). In case of hot strips, the chemistry was suitably modified with leaner alloy chemistry (C: 0.08% max., Mn: 1.5% max., Nb: 0.06% max., V: 0.05% max., and Ti: 0.02% max.) and slabs were control rolled into 10/12mm thick strips followed by accelerated cooling prior to coiling. The mechanical properties of hot strips varied within a narrow range of YS: 535-557MPa, YS/UTS: 0.86-0.88, %El: 33-50%, and Charpy impact toughness property: 150-180J at 0°C showing appearance of finer ferrite grains: 8m. Examination of precipitates in both plates and hot strips revealed presence of fine NbV(CN) and complex M4C3 type coarse carbides. The mechanical properties of Electrical Resistance Welding (ERW) pipes manufactured using hot strips satisfied all specified requirements of American Petroleum Institute (API) norms. Both the products are now ready for their commercial exploitation. © Taylor & Francis Group, LLC.
Sahoo B.K.,Indian Institute of Technology Kharagpur |
Sahoo B.K.,Steel Authority of India Ltd SAIL |
De S.,Indian Institute of Technology Kharagpur |
Meikap B.C.,Indian Institute of Technology Kharagpur |
Meikap B.C.,University of KwaZulu - Natal
Journal of Industrial and Engineering Chemistry | Year: 2015
The transporting of slurries in pipelines depends largely on rheological behavior of the solid-liquid suspension. These rheological properties of slurries are very much influenced by the slurry concentration, particle size distribution and, surface characteristics. The present invention is concerned with the effect of these parameters on slurry rheology using microwave (MW) energy. Microwave pre-treatment for rheological behaviour of iron ore-water slurries (IWS) were carried out in an online Bohlin viscometer. Detailed experimental work for Indian iron ore were conducted at power level of 900. W and 30, 60, 90 and 120. s various exposure times in microwave oven. The microwave treated and untreated test samples were ground for rheological characteristic of slurries. It was seen that microwave-treated ore have better rheological properties as compared to untreated ore. This type of slurry is shear thinning and easy to transport as it exhibited pseudo-plastic behavior. The result showed that microwave-treated iron ore have a density lower than that of untreated ore after grinding. Statistical design analysis was employed to develop empirical equations and found to be encouraging and highly considerable. © 2014 The Korean Society of Industrial and Engineering Chemistry.
Chikhale M.,Iron Ore Business Unit |
Tyagi K.,Iron Ore Business Unit |
Kumar R.,Steel Authority of India Ltd SAIL
IMPC 2014 - 27th International Mineral Processing Congress | Year: 2014
Ore characterisation including mineralogy and beneficiation testwork of an ore is very important for determination of possible products and their quality. The results of such study help in ascertaining the beneficiation process route for the ore. The present study deals with ore characterisation study and beneficiation testwork on the samples of hematite iron ore with goethite impurity. The characterisation study reveals that the hematite is under alteration stage to goethite which has become an integral part of hematite. High goethite/limonite content is enhancing the loss of ignition content of the ore and reducing its Fe content. The findings indicate that in case of hematite iron ore associated with goethite and limonite, it is difficult to achieve high grade of concentrate above 65% Fe. It depends on the amount of goethite and limonite minerals and their association with hematite. These minerals contain aluminous impurities and hence, their rejection becomes essential. Separation of limonite and of goethite to limited extent is possible. In case of goethite, effective liberation is not achieved where it occurs as surface alteration product of hematite grains. The gangue mineral reported are clay and gibbsite, and are closely associated with iron minerals. The test work results indicate the grade and recovery of Fe along with alumina and silica content in lumps, sinter fines and pellet feed fines that can be achieved for the different ore types vis-a-vis the percent of available hematite in the ore. The recovery of iron is dependent on the hematite available and the loss of iron values in tailings is more because of rejection of limonite and goethite.
Roy I.,Steel Authority of India Ltd SAIL |
Halder D.,Steel Authority of India Ltd SAIL |
Singh R.K.,Steel Authority of India Ltd SAIL |
Pradhan R.K.,SAIL Refractory Unit SRU |
And 2 more authors.
InterCeram: International Ceramic Review | Year: 2015
The incorporation of carbon materials is known to significantly enhance both corrosion and thermal shock resistance of refractories. For mixing and placement of refractory castables, water is the most suitable liquid media due to its availability, cost, non-hazardous characteristics and ease of handling. The main factors limiting the development and use of carboncontaining castables are the inferior wettability of carbon by water. Dispersion of carbon-containing materials in water with and without addition of surfactant was tested. By varying the carbon source and keeping the quality and quantity of all other raw materials constant, zero cement castable (ZCC) compositions were designed. The samples were coked and physical properties, oxidation resistance, and pore sizes were measured and FESEM studies carried out. The properties of castables containing processed graphite (PG) and multi-walled carbon nanotubes (MWCNT) were found to be most favourable for the iron and steel industry.
Srikanth S.,Steel Authority of India Ltd SAIL |
Saravanan P.,Steel Authority of India Ltd SAIL |
Joseph A.,Indian Institute for Plasma Research |
Ravi K.,Steel Authority of India Ltd SAIL
Journal of Materials Engineering and Performance | Year: 2013
Plasma nitriding under glow discharge nitrogen plasma has been undertaken on laboratory scale for surface engineering of commercial low carbon steels. The treatment has been shown to confer exceptional improvement in surface properties, viz., hardness and corrosion resistance. The results have been discussed in light of microstructural changes occurring on steel surface and its interior as a result of Fickian nitrogen diffusion and correlated with influences of nitriding-temperature and alloying elements (Mn, Nb, and Si) in steel. © ASM International.
Sarkar B.,Steel Authority of India Ltd SAIL |
Jha B.K.,Steel Authority of India Ltd SAIL
Journal of Materials Engineering and Performance | Year: 2011
An experimental steel of the composition (in wt.%) 0.04C-0.81Mn-0.38Si-0. 15Ti-0.01S-0.013P-0.043Al was hot rolled into 4 mm plates at three different temperatures of 1100, 1000, and 900 °C. The yield strengths of these plates were in the range of 434-484 MPa while the ultimate tensile strength varied from 508 to 586 MPa. Elongation values ranged from 13.0 to 17.8%. Hole expansion ratios (k) varied from 23 to 30.7%. In particular, the plate rolled at 1000 °C showed a yield strength of 484 MPa, an ultimate tensile strength of 586 MPa, a total elongation of ∼15%, and a hole expansion ratio of ∼23%. Transmission electron microscopy showed the presence of fine precipitates of titanium carbosulfide (∼10-50 nm). Therefore, maximum precipitation strengthening was obtained in the plate that was hot rolled into a thickness of 4 mm at 1000 °C. © 2011 ASM International.
Bhakat A.K.,Steel Authority of India Ltd SAIL |
Datta R.,Steel Authority of India Ltd SAIL |
Jha B.K.,Steel Authority of India Ltd SAIL |
Pradhan M.K.,Steel Authority of India Ltd SAIL |
Muthuswamy C.,Steel Authority of India Ltd SAIL
SAE Technical Papers | Year: 2014
Development of economical, as rolled, high strength low alloy steels is the requirement of the day due to its unique features such as increased strength, toughness, formability and weldability property. These materials are required for a variety of critical applications such as long and cross members of auto chassis, pre-engineered building (PEB) structures etc. In line with the developmental trend and market requirement, special quality hot rolled formable grades such as HSFQ 350/ 450 (High Strength Formable Quality) have been selected for development at Rourkela Steel Plant (RSP). The newly developed HSFQ hot rolled steel possess an attractive combination of strength and formability property which is typically quantified as high elongation (25 % min) and hole expansion ratio (145 % min) coupled with lower YS/UTS ratio (0.80-0.85). This has been possible as a result of innovative alloy design and synergistic effect of Nb & Si during controlled processing. Similarly medium carbon steels are being used for wide range of automotive applications. Selected difficult-to-cast medium carbon grades e.g. MC 40 & MC 55 have been successfully developed and subsequently commercialized at integrated steel plant. The metallurgical factors contribute for development of these grades are control of Al (< 0.04 %) & N content (∼60 ppm) along with control of excessive segregation of carbon in the steel and presence of inclusions like aluminium oxide and MnS which are mainly responsible for inadequate cold reducibility. Copyright © 2014 SAE International.
Das S.K.,Steel Authority of India Ltd. SAIL |
Nandy A.S.,Steel Authority of India Ltd. SAIL |
Paul A.,Steel Authority of India Ltd. SAIL |
Sahoo B.K.,Steel Authority of India Ltd. SAIL |
And 2 more authors.
Coke and Chemistry | Year: 2013
A by-product coke making plant is required to supply sufficient coke of good quality and adequate gas of high calorific value for the integrated steel plant to be a going concern. The one element that influences the handling of coal and impacts the operation and efficiency of the plant is moisture. Compared to other important properties of the coal blend, moisture can be easily manipulated. The coal moisture can be increased simply by adding water through hose pipes. Also, it can be reduced to 5-6 mass percent using Coal Moisture Control (CMC) and 2-4 mass percent using Dry-cleaned & Agglomerated Pre-compaction System (DAPS). Moisture content is one among the many variables affecting the bulk density of coal blend and those controlling the coke qualities and yield. Increase in moisture reduces coal grindability, coking pressure and internal gas pressure; helps in dust suppression during charging and hence reduces jamming of ascension pipes and hydraulic main. Batteries charging coals with high moisture content are not troubled with roof carbon deposits. It was observed that when moisture content in coal blend of SAIL-Bokaro Steel Plant increased to more than 8.50%, the calorific value of coke oven gas improved. In the working moisture range of 9-11%, the increase of the yield of coke oven gas per 1% of working moisture is 5.2 m3. Studies have shown, however, that the increase in moisture content of coal beyond 8% hampers strong coke formation. Pre-carbonization preheating process generally showed an increase in the proportion of 40-80 mm coke, compared with wet charges. For SAILBokaro coke ovens, driving out 1% moisture from coal blend requires 125 Mega-calories of heat/oven. With lesser moisture, the emission of NOx in atmosphere will also be low. On using dry to low moisture coal blend, the swelling of coke mass increases leading to difficulty in oven pushings. Hence, an optimum level of moisture content of charge coal needs to be maintained for improving coke oven productivity, coke quality and operational smoothness. The coke oven managers all around the globe maintain this optimum level according to their requirement, the operating conditions, the quality of product and by products, the oven health & age and the ease of handling. © 2013 Allerton Press, Inc.
Khan S.,Steel Authority of India Ltd SAIL |
Selvi M.S.,Steel Authority of India Ltd SAIL |
Manjushree M.,Steel Authority of India Ltd SAIL |
Paul A.K.,Steel Authority of India Ltd SAIL
Steel Times International | Year: 2011
Knowledge management (KM) is an integrated systematic approach to identify, manage, and share an organization's information assets available in databases, documents, policies, and procedures, and unarticulated expertise and experience held by individuals. It helps in the efficient use of the human knowledge that exists within an organization. Software may be developed to create and search knowledge content from a knowledge base and the content may be made available to others by web based user friendly interfaces. A KM audit would be ideal at the early stage to understand where, what and how the knowledge exists, what kind of processes is considered to create the content of KM, and audience aimed. Knowledge Centred Support (KCS) has emerged as the most complete and effective approach to the practice of knowledge management in service and support industries.
Khan S.,Steel Authority of India Ltd SAIL |
Prasad B.V.N.,Steel Authority of India Ltd SAIL |
Selvi S.,Steel Authority of India Ltd SAIL |
Rani U.,Steel Authority of India Ltd SAIL |
And 2 more authors.
2015 International Conference on Computing for Sustainable Global Development, INDIACom 2015 | Year: 2015
Knowledge management has become an important aspect of any enterprise today. In today's competitive environment capturing and sharing of knowledge are important for correct and timely decisions. Knowledge can be classified as mission critical, confidential or open knowledge. It may exist in variety of sources, formats and devices viz, in people's heads, databases, files etc. According to Larry Prusak, Executive Director of the Institute for Knowledge Management, the practice of Knowledge Management (KM) is "getting the right knowledge in the right context to the right people at the right time." Knowledge Management is an integrated approach to identify, create, manage, share, and exploit all information and knowledge assets of an organization. Knowledge is of different types namely tacit and explicit. Tacit knowledge is possessed by people and difficult to capture or share. Explicit knowledge is reasonably self-contained. The users can understand easily and learn how to use the same effectively. In this paper we have discussed about a system that is based on the concept of organizational document management system (DMS) for capturing explicit knowledge available in organization in the form of reports, documents etc. for sharing among the users. The system has been implemented successfully. © 2015 IEEE.