Electric steel process

Steel production Steelmaking can be performed according to two main routes, to which reference can be made as based on the basic oxygen converter and the electric steel process, respectively. The basic oxygen converter... 

Core-Loss Limits. In the United States, flat-roUed, electrical steel is available in the following classes (12) nonoriented, fiiUy processed nonoriented, semiprocessed nonoriented, fiiU-hard and grain-oriented, fiiUy processed. Loss limits are quoted at 1.5 T (1.5 x lO" G). The loss limits at 1.7 T (1.7 X ICf G) of the fourth class and of the high induction grades are shown in Table 2. Typical appHcations include use for transformers, generators, stators, motors, ballasts, and relays. 

The electric arc furnace process accounted for about 25% of the 1982 U.S. steelmaking capacity (14). Most of the raw material used for the process is steel scrap. Pollutants generated by the electric furnace process are primarily particulate matter and CO. The furnaces are hooded, and the gas stream containing the particulate matter is collected, cooled, and passed to a bag-house for cleaning. Venturi scrubbers and ESPs are used as control devices at some mills. Charging and tapping emissions are also collected by hoods and ducted to the particulate matter control device. 

Electric arc process. Patented by Siemens in 1878, this u.ses an electric current through the metal (direct-arc), or an arc just above the metal (indirect-arc), as a means of heating. It is widely used in the manufacture of alloy- and other high-quality steels. 

Imatra Also called the Solid Lime Process. A method for desulfurizing steel made by an electric arc process. Additions are made of burnt lime (calcium oxide), fluorspar (mineral calcium fluoride), and ferro-silicon. 

Electric Iurnace Processes. Electric furnaces have been used for several decades to produce special steels lor which the open-hearth process was not suitable. 

Electric-furnace process. One of the highest grades of steel now produced is made in electric furnaces in which steel from the Bessemer or open-hearth process is subjected to further refining. The steel produced in this relatively new process is characterized by its high density and the absence of occluded gases. The chief advantage of this process is its provision for more precise control of temperature. 

COGENERATION OF ELECTRICITY AND PROCESS STEAM IN STEEL PLANTS 40 MW electricity for 10,000 Ton per day plant 41.4 x 106 34.6 x 109 per Quad of electricity 1-3/4 Times Conservation... 

The conventional electric RSW process can be problematic for many new high-performance lightweight structural materials such as aluminum alloys and advanced high-strength steels (AHSS) (Ref 29, 30). The great emphasis on... 

Soft ferromagnetic materials for ac applications are usually prepared in the form of thin laminated sheets (essentially to decrease eddy-current losses see the end of this section). A proper combination of rolling and annealing processes can lead to a preferential orientation of grains, which results in extremely favourable magnetic properties. The fabrication steps for electrical steels are listed in Table 6.3. 

G. Diaz, D. Martin and C. Lombera, Zinc Recycling Through The Modified Zincex Process , Paper presented at the 2" Intemational (inference on the Recycling of Metals, Amsterdam. CThe Netherlands . October 1994. the 5 European Electric Steel Congress, Paris, France, June 1995. 

In this method, electric field-assisted polymerization of monomer units takes place over the electrically conducting substrate. Any electrically conductive substrate can be used for the same purpose like metal plate, steel plate, etc. Application of electric field results in the formation of polymer chains. The electric field can be adjusted in two ways either in terms of electric potential or in terms of electric current. There will be a threshold potential for the polymerization to start. Knowledge on this optimal potential is mandatory for the polymer synthesis as the potential may be different for different polymers. For different nanostructures such as nanoparticles, thin films, etc., there should be proper optimization in various parameters such as electric field, processing time, temperature, and the process atmosphere. Any variation in these parameters may lead to a change in size and shape of the polymer. For example, in a prolonged elec-tropolymerization process, thick polymeric films are formed. 

For several years TVA produced calcium metaphosphate, Ca(POs)2, in a demonstration-scale plant. The process consisted of burning elemental phosphorus and reacting the resulting P2O5 vapor with phosphate rock. The molten product was tapped out of the ftirnace and -solidified on a watei cooled steel drum [17]. The resulting vitreous flakes were cooled further and crushed to pass a 10-mesh screen (about 1.6 mm). Development of a process for production of calcium metaphosphate involved three pilot plants and three demonstration-scale plants and a considerable amount of laboratory- and bench-scale work [IS]. The third demonstration-scale plant was technically successful and operated about 16 years, starting in 1949. A total of nearly 1 miflion tonnes was produced, including relatively small amounts from the first and second demonstration-scale plants. The process was economically competitive with TSP when both products were based on elemental phosphorus made by the electric-furnace process. 

A recent technology development in the production of GO electrical steel is the combination of thin slab casting, direct hot rolling, and acquired inhibitor formation. This practice combines tbe advantages of low temperatures, process-shortening, microstructural homogeneity, improved strip geometry, and better surface condition of the products. The slab thick-... 

Stator and rotor losses. This specially processed steel includes thinner laminations as well as silicon electric steels. 

The application of EDM is mostly known for steel processing only. But aluminum can easily be processed with EDM with even higher (for the most part) removal rates compared to steel. Eurthermore, the so-called white layer (which is extremely hard for steel) does not form, so that any necessary polishing can be reduced to a minimum. The EDM technologies that are mainly applied in practice are divided into two methods the planetary-EDM (P-EDM process) and the wire EDM (electrical discharge wire cutting or EDC process). 

Iron is converted into steel by the Bessemer, Siemens-Martin or electrical processes. Iron can be rendered passive by contact with con-... 

Fluorine cannot be prepared directly by chemical methods. It is prepared in the laboratory and on an industrial scale by electrolysis. Two methods are employed (a) using fused potassium hydrogen-fluoride, KHFj, ill a cell heated electrically to 520-570 K or (b) using fused electrolyte, of composition KF HF = 1 2, in a cell at 340-370 K which can be electrically or steam heated. Moissan, who first isolated fluorine in 1886, used a method very similar to (b) and it is this process which is commonly used in the laboratory and on an industrial scale today. There have been many cell designs but the cell is usually made from steel, or a copper-nickel alloy ( Monel metal). Steel or copper cathodes and specially made amorphous carbon anodes (to minimise attack by fluorine) are used. Hydrogen is formed at the cathode and fluorine at the anode, and the hydrogen fluoride content of the fused electrolyte is maintained by passing in... 

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