Steelmaking the refining of iron to make steel is where the carbon content of hot metal is lowered, usually to less than 1 % by an oxidation process in a. Steelmaking the refining of iron to make steel is where the carbon content of hot metal is lowered, usually to less than 1 % by an oxidation process in a steelmaking furnace. The effects of other elements can be estimated by equating them to an additional amount of carbon. Steel making online course video lectures by iit kanpur. What is the difference between primary and secondary tmt. To develop computational and mathematical abilities to be applied for process design and control.
Before undertaking a detailed study of the processes involved in steelmaking. The major development of the clu process was the idea to use superheated steam as the diluting gas instead of argon ar gas which is used in the aod process. Feb 29, 2008 this authoritative account covers the entire spectrum from iron ore to finished steel. The result is high performance and productivity levels of both supplied and modernized plants combined with impressive cost savings in secondary metallurgy. Directly reduced iron directly reduced iron is a product of iron steel direct reduction from ores in the solid. Introductory remarks,a historical perspective,an overview of modern iron and steelmaking,energy in iron and steel industry,environmental, health and safety ehs issues environmental issues health and safety issues,iron and steel. This plant consists of an oxygen steelmaking furnace kobm and. In the first step, the raw inputs iron ore, coke, and lime are melted in a blast furnace. Our expertise as the world leader in stainless steelmaking technology supports producers to boost their productivity and performance. Actual process data as well as energy input, material addition and. The hollow interior of the oscillating molds have inside dimensions corresponding to the. Linzaus tria, october 20 06 secondary steel making session pa per no. Modern steelmaking can be broken down into six steps.
Secondary steelmaking refractories a practical training seminar. Koria,department of material science and engineering,iit kanpur. Steel making carbon equivalent to a good approximation, the weldability of steel can be estimated from its chemical composition. Pig iron is divided into steelmaking pig iron, which is intended for further processing to steel by various refining processes, and foundry pig iron, from which cast iron is produced by remelting. Melting steel scrap results in liquid steel, which can be shaped in the desired forms by casting, rolling and finishing. Open discussions will allow participants to gather additional.
Table 1 represents the material inputs to each operation in secondary metallurgical industries. Steelmaking is the process of producing steel from iron ore andor scrap. The most significant alloying element effecting weldability is carbon. Be able to understand basic layout of blast furnace, steelmaking shop and continuous casting process. An opentopped cylindrical container made of heavy steel plates and lined with refractory, the ladle is used for holding and transporting liquid steel. In principle, steelmaking is a melting, purifying, and alloying process carried out at approximately 1,600 c 2,900 f in molten conditions. Diy brick rocket stove cooking without power duration. Secondary refining american iron and steel institute. This is this method is often called as ladle metallurgy.
Depending on the types of steel required, the following secondary steelmaking processes can be used. By the time that secondary steelmaking is complete, the metal should be within specification. What is steel is an alloy of iron and carbon containing less than 2% carbon. From alloy handling to degassing, desulfurization and decarburization, secondary metallurgy is indispensable to the production of highquality steel. What is the difference between a primary steel and a. Direct reduction scrap ladle refining electric arc furnace steelmaking iron ore pellets electric arc furnace steelmaking continuous casting design by cover photo. Steelmaking process an overview sciencedirect topics. Steel making is the method of processing and producing steel from iron ore and scrap. This is a batch process with a cycle time of about two to three hours. Secondary steelmaking is a step between steel production and primary processes. Steel making molten iron is a key ingredient in the steelmaking process which takes place in the slabmaking plant. Whereas mini mills operate successfully at 100,000 tonnes p. Ultralow carbon, ultralow sulphur, low nitrogen and hydrogen contents, as well as a high degree of steel cleanliness are achieved through the application of vacuum degassing units. The difference is basically in the steel making process.
Steps in the modern steelmaking process the balance. Eaf methods, alternatively, feed recycled steel scrap through use high power electric arcs temperatures up to 1650c to melt the metal and convert it to highquality steel. Oxygen is used to decarburize the molten steel and provide thermal energy. Nowadays integrated steelworks are rarely viable at less than 3 million tonnes p. A lot of the carbon will be removed, but aluminium will take its. Presentations will provide data from steelmaking operations, and attendees will benefit from the practical experience of the presenters, including the application of the latest tools and techniques being used. In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon most important impurity are removed from the sourced iron, and alloying elements such as manganese, nickel, chromium, carbon and vanadium are added to produce different grades of steel. Generally speaking, energy constitutes a significant portion of production cost, from 20% to 40%, according to the estimation from world steel association 7. Secondary metallurgical processes are the production processes that starts with the output of the ore reduction process, scrap etc as the input to the industry and its products is semifinished products, finished products. Nov 30, 2017 the difference is basically in the steel making process. Live simple, live free tinyhouse prepper recommended for you. It begins by tracing the history of iron and steel production, right from the earlier days to todays world of oxygen steelmaking, electric steelmaking, secondary steelmaking and continuous casting. The secondary steelmaking module is part of the steel manufacturing course. Aist is recognized as a global leader in networking, education and sustainability programs for advancing iron and steel technology.
Scrap steel is charged to begin a cycle, and alloying agents and slag materials are added for refining. About 95% of energy for an integrated steelmaking plant comes from solid fuel mainly coal, 34% from gaseous fuel and 12% from liquid fuel. The process is known as basic because fluxes of burnt lime or. It also uses liquid steel from an electric arc furnace eaf or any other similar primary steel making furnace. The next step targets on alloying it by adding various elements like manganese, chromium. Ironmaking and steelmaking metallurgical and materials.
The refining technology for rail steel includes the following processes as shown in figure 3. A lot of the carbon will be removed, but aluminium will take its place to create a drawing quality steel. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. Overview of the steelmaking process pellets sinter limestone. The grading is based on which elements are still in the metal, such as carbon dioxide. Since scrap metal is used instead of molten iron, no coke making or iron making operations are associated with steel production using an eaf. Various chemical reactions are initiated, either in sequence or simultaneously, in order to arrive at specified chemical compositions and temperatures. This authoritative account covers the entire spectrum from iron ore to finished steel.
Basic oxygen steelmaking bos, bop, bof, or osm, also known as linzdonawitzsteelmaking or the oxygen converter process is a method of primary steelmaking in which carbonrich molten pig iron is made into steel. The steel flows out at a steady rate into oscillating molds. There are a few operations conducted in ladles include deoxidation or killing. Abstract todays production of highquality steels along the bof route would be unthinkable without the application of secondary metallurgy. The quality of the iron ore is mainly determined by its composition. Aod argon oxygen decarburization process a process primarily used in stainless steel making high grades alloys with oxidizable elements. Iron ore is a mineral aggregate that can be converted economically into iron. Modern methods, however, are still based the same premise as the bessemer process, namely, how to most efficiently use oxygen to lower the carbon content in iron. The eaf method, however, feeds recycled steel scrap through highpower electric arcs with temperatures of up to 1,650 degrees celsius to melt the metal and convert it into highquality steel. Smelting reduction technologies cokeovensinterbf route used by integrated steel plants that produce steel from iron ore. It does not include normal alloying prac tice in the furnace or at the ladle during tapping. Not all steel plants produce all of the products shown in this diagram.
Accordingly, plant operators must invest in process optimization and expand capacity to remain competitive on an international basis. Open hearth process an overview sciencedirect topics. Cycles, or heats, range from about 112 to 5 hours to produce carbon steel and from 5 to 10 hours or more to produce alloy steel. The steel expert supervision model cyclically determines the actual heat status. Steel making steel making process gerdau ameristeel utilizes the electric arc furnace continuous casting method in the. Pig iron is divided into steel making pig iron, which is intended for further processing to steel by various refining processes, and foundry pig iron, from which cast iron is produced by remelting.
Oct 05, 2017 secondary steel making processes aod argon oxygen decarburization clu creusotloireuddeholm vod vacuum oxygen decarburization lf ladle furnace 15. This is done by adding or removing certain elements andor manipulating the temperature and production environment. Primary steel is acquired from a steel making process known as bof, also know as converter process. Pdf influence of steelmaking processes on the quality. What is the difference between primary and secondary tmt bars. Secondary steelmaking involves treating the molten steel produced from both bos and eaf routes to adjust the steel composition. View enhanced pdf access article on wiley online library html view download pdf for offline viewing.
Primary steelmaking, ladle metallurgy, ingot casting, continuous casting. Secondary steelmaking refractories a practical training. Apart from primary steelmaking process, there is secondary steelmaking process commonly performed in ladles. The casob process enables consistently high alloy recoveries and the reheating of steel using the exothermic reaction between oxygen and aluminum. In this simulation you will play the role of plant metallurgist in charge of secondary steelmaking operations. Secondary steel making processes iaod process iivod process iiiclu process ivladle furnace 5. This work helps to select the optimum secondary steel making process route for producing lpg grade steel depending upon composition of liquid steel input to secondary steel making units. Table 1 material inputs in secondary metallurgical processes process material inputs furnaces induction and electric arc furnace preheating furnace cupola and crucible furnace steel scrap, liquid steel, direct reduced.
This module introduces the learner to the critical step of refining the chemistry of the steel in order to impart the desired properties required for the grade of steel being produced. Introduction to the production of clean steel saimm. However, scrap steel, both quantitatively and qualitatively, cannot meet the entire demand for steel. In some converters oxygen is blown through the bottom and the process is bottom blown converter.
The demand for stainless steel increases each year, as well as the price pressure. The industry also plays a major role in recycling steel. Jan 14, 2020 secondary steelmaking involves treating the molten steel produced from both bos and eaf routes to adjust the steel composition. Pdf secondary metallurgy for bof steelmaking researchgate. The production of steel in an eaf is a batch process. The processes of desulfurization pretreatment, secondary refining, and vacuum degassing are designed to purify the steel, improve the interior. The different grades of steel are used for different tasks. An electric arc furnace eaf is a furnace that heats charged material by means of an electric arc industrial arc furnaces range in size from small units of approximately one ton capacity used in foundries for producing cast iron products up to about 400 ton units used for secondary steelmaking. Indeed, many of the reactions interfere with one another. Secondary steelmaking involves refining of the crude steel before casting and the various. Objectives presenting general steel making introduction giving knowledge about steel classification providing information about steel making 3. Secondary steelmaking physical chemistry of metallurgical. Pdf todays production of highquality steels along the bof route would be.
In the bar chart at the top of the page, you can see how the composition of the steel that is ready for casting compares with the metal that the customer ordered. Secondary steel making draft free download as powerpoint presentation. The six steps of modern steel manufacturing melfab. Here all secondary metallurgical work takes place, including deslagging and reslagging, electrical heating, chemical heating or cooling with scrap, powder injection or wire feeding, and stirring with gas. The australian iron and steel sector is a fundamental building block for many activities in the australian economy, providing a key material for construction, infrastructure, resource developments and other manufacturing, including the automotive industry. It focuses on removing the slugs and other unwanted materials like phosphorus, sulphur, silicon, nitrogen, and excess carbon from the raw iron.
After this process has finished, we have raw steel. Mar 23, 2019 let me answer it in short and simple words. You will take charge of a ladle of molten steel from the basic oxygen furnace bof, and attempt to deliver it to the appropriate caster at the specified time, composition, temperature and inclusion content cleanness. Nowadays, secondary steelmaking units have become an essential part of the integrated steel. Salzgitter the process shown above is illustrative only and is not designed to show the steelmaking process in detail.
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