Learn more about Praxair’s Argon Oxygen Decarburization process that is used to make over 75% of the world’s stainless steel. Argon Oxygen Decarburization (AOD) Treatment is the recognized standard for stainless steel refining worldwide. Whether you are producing castings, wrought . Argon Oxygen Decarburization, frequently referred to as “AOD”, is an advanced technology for the refinement of iron, nickel, and cobalt based alloys. By.
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Decarburzation of the recent converter installations include the use of a top lance for blowing oxygen. Unsourced material may be challenged and removed. Bottom injection usually improves wear decarburizztion in the barrel section of the converter. Usually, the converter is turned down to a horizontal position and a sample of the liquid steel is taken for analyses at a carbon level of about 0. The next step is the reduction step, in which the reduction additions are charged and stirred with an inert gas for a desired time.
argon-oxgen To achieve this, alloy additions are made with elements that have a higher affinity for oxygen than chromium, using either a silicon alloy or aluminum. For example, with starting sulphur of 0. The slice portion allows the crane to come close to the converter mouth. The process is very popular because it combines higher metallic yields with lower material costs.
AOD Refining | Argon Oxygen Decarburization | MetalTek
This accretion protects the tuyere and surrounding refractory. At any given time, one of the converters is in the tiltable trunnion ring refining steel, a second newly lined converter is at a preheating station, and the third converter is at a reline station.
The burning of carbon increases the bath temperature. Haynes International Case Study Video. Low hydrogen Short circuit.
Articles needing additional references from November All articles needing additional references. In general, the bath temperature is controlled to less than deg C. The process is so popular because it combines higher metallic yields with lower material costs. For converters that tap into a ladle held by a crane, a sliced cone top section is often used.
Typical internal volumes of AOD converters are in the range 0. Decarburizatlon ratio is lowered with the progress of the decarburization.
After a desired carbon and temperature level have been reached the process moves to reduction. Process gases are injected through submerged tuyeres that are installed in the side wall or bottom of the converter.
Ingot (AOD Refining)
These tuyeres typically consist of a copper tube with a stainless steel outer tube. After tapping, the ladle is often stirred for composition homogenization and temperature uniformity along with flotation of inclusions. During the oxygen blow, silicon is oxidized before carbon. Any chromium oxide not reduced by carbon ends up in the slag, which can form a complex spinel.
AOD provides an economical way to produce stainless steel with a minimal loss of precious elements. Please help improve this argon-oxygenn by adding citations to reliable sources.
The decarburization step is controlled by ratios of oxygen to argon or nitrogen to remove the carbon from the metal bath. The installation of a lance and introduction of oxygen in the early stages of decarburization can reduce the time for a heat. Electro-slag remelting Vacuum arc remelting Argon oxygen decarburization. Decarburization occurs on the surface of rising bubbles that form from either the inert gas that is injected or on the surface of chromium oxide particles that are being reduced and generating carbon mono decarburozation CO.
Praxair can quote a server-only option for these systems.
Bottom blown converters have a variety of tuyere configurations depending on flow rates required. Smelting Bloomery produces sponge iron Blast furnace produces pig iron Cold blast Hot blast Anthracite iron Direct reduced iron. During decarburization, additions are made for obtaining the proper final chemical composition. The end result is a cleaner metal coupled with increased productivity.
Argon oxygen decarburization – Wikipedia
After the change from nitrogen to argon, nitrogen is removed from the bath both by evolved carbon monoxide and argon. American inventions Stainless steel Steelmaking. The liquid metal is transferred from transfer ladle to AOD converter.