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How the Austenite Ferrite Balance Achieved By yaang.com
To understand how duplex stainless steel works, first compare the composition of two familiar steel austenitic 304 (1.4301) and ferritic 430 (1.4016). Structure Grade EN Number C Si Mn P S N Cr Ni Mo Ferritic 430 1.4016 0.08 1.00 1.00 0.040 0.015 - 16.0/18.0...
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Corrosion Resistance of Duplex Stainless Steel By yaang.com
The range of duplex stainless steel allows them to be matched for corrosion resistance with the austenitic stainless steel and ferritic stainless steel grades. There is no single measure of corrosion resistance . However, it is convenient to use the Pitting...
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1.4410 2507 S32750 Super Duplex Stainless Steel By yaang.com
2507 S32750 Super Duplex Stainless Steel is super duplex stainless steel with 25% chromium, 4% molybdenum, and 7% nickel designed for demanding applications which require exceptional strength and corrosion resistance , such as chemical process, petrochemical,...
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Ferritic Stainless Steels By yaang.com
Ferritic Stainless Steels are, in principle, ferrite at all temperatures. This is achieved by a low content of austenitic forming elements, mainly nickel, and a high content of ferrite forming elements , mainly chromium. Ferritic types, such as 4003 and...
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Super Ferritic Stainless Steel By yaang.com
Super ferritic Stainless Steel has a structure and properties similar to the common ferritic alloys, but they contain enhanced levels of chromium and molybdenum to increase their resistance to high temperature and corrosive environments such as seawater....
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Compared Ferritic Stainless Steel with Duplex Stainless Steel By yaang.com
High content of alloying elements, the price is relatively high, generally free of nickel ferrite . In summary, you can generally see the use of DSS performance and process performance of the general picture that, with its superior mechanical and corrosion-resistant...
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Calculation of Pitting Resistance Equivalent Numbers PREN By yaang.com
Pitting resistance equivalent numbers (PREN) are a theoretical way of comparing the pitting corrosion resistance of various types of stainless steel , based on their chemical composition . The PREN (or PRE) numbers are useful for ranking and comparing...
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Stainless Steel Corrosion By yaang.com
Why have stainless steel rust? When the stainless steel surface of brown rust (points), people is not great surprise of stainless steel, and steel may be a problem. In fact, this is a lack of understanding of stainless steel. Stainless steel Kind of one-sided...
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Corrosion Resistant Material By yaang.com
In normal mechanical and structural engineering design materials are selected primarily for their mechanical properties -corrosion is not an important criteria. The systems are generally protected against corrosion by surface coatings . Most machines...
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Bi-Metallic Corrosion Galvanic Corrosion By yaang.com
Bi-Metallic corrosion Galvanic Corrosion is the additional corrosion that occurs when dissimilar metals are in contact in the presence of an electrolyte. The corrosion of a metal, the anode, results from the positive current flowing from the anode to...
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Intergranular Corrosion of Stainless Steel Tubes By yaang.com
When austenitic stainless steel tubes are heated or cooled through the temperature range 425-900C (800-1650F), chromium tends to combine with carbon to form chromium carbides. The carbides precipitate preferen- tially at grain boundaries depleting chromium...
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Corrosion Resistance of Stainless Steel Tubes By yaang.com
Carbon steel suffer from 'general' corrosion, where large areas of the surface are affected. Stainless steel tubes in the passive state are normally protected against this form of attack, however, localised forms of attack can occur and result in corrosion...
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Use of Subsea Stainless Steel Pipeline By yaang.com
One of the first major subsea stainless steel pipeline was built between Great Britain’s Isle of Wight and the coast of France during World War II and since then, their use has expanded exponentially. Today, undersea stainless steel pipes are mostly used...
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How Does Offshore Stainless Steel Pipeline Installation Work? By yaang.com
Laying pipe on the seafloor can pose a number of challenges, especially if the water is deep. There are three main ways that subsea stainless steel pipe is laid -- S-lay, J-lay and tow-in -- and the pipelay vessel is integral to the success of the installation....
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Common Name for Chemical and Selection of Stainless Steel By yaang.com
The 'appropriate grades' notes are taken from the Avesta Sheffield Corrosion Handbook and are shown for general guidance only. Specific grade selection should be rechecked with corrosion tables. A link to the SST ORG web site article that describes where...
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Selection of Stainless Steel for Cryogenic Application By yaang.com
Ferritic , martensitic and duplex stainless steel tend to become brittle as the temperature is reduced, in a similar way to other ferritic / martensitic steel. The austenitic stainless steel such as 304 (1.4301) and 316 (1.4401) are however 'tough' at...
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Properties at Cryogenic Temperatures of Stainless Steel Tubes By yaang.com
The austenitic stainless steel tubes remain tough and ductile to very low temperatures. Metals such as iron and constructional steel undergo a marked decrease in ductility at lower temperature. Common Cryogenic Temperatures: Environment Degrees C Degrees...
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Selection of Stainless Steel for Sulphur Dioxide SO2 and SO3 By yaang.com
Sulphur dioxide dissolves readily in water, which is then classed as a weak reducing acid (sulphurous acid H2SO3). The oxidation of sulphur dioxide can be assisted by chlorine. Sulphuric acids and hydrochloric acids can be formed in aqueous (water) systems....
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Selection of Stainless Steel for Handling Phosphoric Acid H3PO4 By yaang.com
Phosphoric Acid is also know as orthophosphoric acid and is classed as a weak acid. Austenitic stainless steel have goodcorrosion resistance to chemically pure phosphoric acid. Wet process phosphoric acid (WPA) can be aggressive. It is used as a chemical-cleaning...
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Selection of Stainless Steel for Handling Hydrofluoric Acid HF By yaang.com
Hydrofluoric Acid is extremely aggressive and attacks most metals and glass. The approach to the selection of stainless steel is similar to that for hydrochloric acid. Commercially concentrated acid is around 40wt. %. Plastics are normally considered...
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Selection of Stainless Steel for Handling Ammonia NH3 By yaang.com
Ammonia at normal atmospheric temperature and pressure is a gas. It can be stored under pressure as a liquid or below it's atmospheric boiling point of -34 degC. It has been assumed that there is no corrosion risk to stainless steel that are normally...
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Selection of Stainless Steel for Handling Chlorine Cl2 and ClO2 By yaang.com
Chlorine is a powerful oxidising agent. It normally occurs as a gas but can be liquefied under pressure at ambient temperature . As a dry gas it does not tend to be aggressive towards stainless steel , but as either a damp gas or dissolved in water it...
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Selection Stainless Steel for Handling Sulphuric Acid H2SO4 By yaang.com
Sulphuric acid is oxidising when concentrated but is reducing at low and 'intermediate' concentrations. The response of most stainless steel types is that in general they are resistant at either low or high concentrations, but are attacked at intermediate...
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Selection Stainless Steel for Handling Sodium Hydroxide NaOH By yaang.com
Sodium Hydroxide (Caustic Soda) is a strong base. It is used in metal degreasing and cleaning processes in a wide range of industry applications. Stainless steel types 304 and 316 can be considered resistant below 80 degC, up to the limit of solubility....
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Selection of stainless steel for handling acetic acid CH3COOH By yaang.com
Acetic acid is a weak reducing acid. It is used in plastics manufacture and is a constituent of foods as vinegar. Ferritic stainless steels such as 430 type can be considered but normally the 304 types are used for most applications, including handling...