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Stainless steels erosion-corrosion

Stainless steel and nickel base alloys are generally resistant to erosion corrosion. Because the vessel internals are made of stainless steel, erosion corrosion resistance of BWR vessel internals has been excellent under design basis operating conditions... [Pg.61]

Most metals and alloys are susceptible to erosion-corrosion damage. Many depend upon the development of a surface film of some sort (passivity), for resistance to corrosion. Examples are aluminum, lead, and stainless steels. Erosion-corrosion results when these protective surfaces are damaged or... [Pg.51]

Titanium resists erosion—corrosion by fast-moving sand-laden water. In a high velocity, sand-laden seawater test (8.2 m/s) for a 60-d period, titanium performed more than 100 times better than 18 Cr—8 Ni stainless steel. Monel, or 70 Cu—30 Ni. Resistance to cavitation, ie, corrosion on surfaces exposed to high velocity Hquids, is better than by most other stmctural metals (34,35). [Pg.104]

The metallurgy of the cyclone equipment has in recent years focused primarily on type 304 H stainless steel. The 304 H material is durable and easy to fabricate and repair, withstands the high regenerator temperatures, and is oxidation- and corrosion-resistant. Essentially all internal surfaces of the cyclone that are subject to erosion are protected with a 2 cm layer of erosion-resistant lining. When installed and cured, most refractory linings are highly resistant to erosion. [Pg.218]

Metals that depend on a relatively thick protective coating of corrosion product for corrosion resistance are frequently subject to erosion-corrosion. This is due to the poor adherence of these coatings relative to the thin films formed by the classical passive metals, such as stainless steel and titanium. Both stainless steel and titanium are relatively immune to erosion-corrosion in most cooling water environments. [Pg.240]

For inlet or outlet end erosion-corrosion, either extend tube ends 3 or 4 inches into the water box or install sleeves, inserts, or ferrules into the tube ends. These should be a minimum of 5 inches long. The ferrules may be nonmetallic or erosion-resistant metals, such as stainless steel, if galvanically compatible. The end of the ferrule should be feathered to prevent turbulence. [Pg.249]

Because alterations to equipment design can be cumbersome and expensive, a more economical approach may be to change the metallurgy of affected components. Metals used in typical cooling water environments vary in their resistance to erosion-corrosion. Listed in approximate order of increasing resistance to erosion-corrosion, these are copper, brass, aluminum brass, cupronickel, steel, low-chromium steel, stainless steel, and titanium. [Pg.249]

The resistance of a metal to erosion-corrosion is based principally on the tenacity of the coating of corrosion products it forms in the environment to which it is exposed. Zinc (brasses), aluminum (aluminum brass), and nickel (cupronickel) alloyed with copper increase the coating s tenacity. An addition of V2 to 1)4% iron to cupronickel can greatly increase its erosion-corrosion resistance for the same reason. Similarly, chromium added to iron-base alloys and molybdenum added to austenitic stainless steels will increase resistance to erosion-corrosion. [Pg.249]

Dents in tubing can induce erosion failures, especially in soft metals such as copper and brass. Welding and improper heat treatment of stainless steel can lead to localized corrosion or cracking through a change in the microstructure, such as sensitization. Another form of defect is the inadvertent substitution of an improper material. [Pg.316]

Galvanic corrosion may also occur by transport of relatively noble metals, either as particulate or as ions, to the surface of an active metal. For example, ions of copper, perhaps resulting from corrosion or erosion-corrosion at an upstream site, may be carried by cooling water to the surfaces of aluminum, steel, or even stainless steel components. If the ions are reduced and deposit on the component surfaces, localized galvanic corrosion may result. [Pg.358]

Erosion and Corrosion combined require special consideration. Most of the stainless steels and related corrosion-resistant alloys ow e their surface stability and low rate of corrosion to passive films that develop on the surface either prior to or during exposure to reactive fluids. If conditions change from passive to active, or if the passive film is removed and not promptly reinstated, much higher rates of corrosion may be expected. [Pg.270]

If the amount of metal removal by erosion is significant the surface will probably be continually active. Metal loss will be the additive effect of erosion and active corrosion. Sometimes the erosion rate is higher than that of active corrosion. The material selection judgment can then disregard coirosion and proceed on the basis of erosion resistance provided the corrosion rates of aetive surfaces of the alloys considered are not much different. As an example of magnitudes, a good high-chromium iron may lose metal from erosion only a tenth as fast as do the usual stainless steels. [Pg.270]

The austenitic cast irons are in widespread use in many industries (food, pharmaceutical, petroleum, chemical, petrochemical, pulp and paper, etc.) in mildly corrosive and erosive situations where the life of unalloyed or low-alloy cast iron or steel is short, but the high cost of stainless steel and nonferrous alloys cannot be justified. [Pg.60]

Tower shells may be ferrous, non-ferrous, stainless alloys or clad (such as monel-clad-steel). The trays are usually light gage metal consistent with the corrosion and erosion problems of the system. The velocity action of vapors flowing through holes and slots accentuates the erosion-corrosion problems, and often a carbon steel tower will use... [Pg.215]

This example of aluminium illustrates the importance of the protective him, and hlms that are hard, dense and adherent will provide better protection than those that are loosely adherent or that are brittle and therefore crack and spall when the metal is subjected to stress. The ability of the metal to reform a protective him is highly important and metals like titanium and tantalum that are readily passivated are more resistant to erosion-corrosion than copper, brass, lead and some of the stainless steels. There is some evidence that the hardness of a metal is a signihcant factor in resistance to erosion-corrosion, but since alloying to increase hardness will also affect the chemical properties of the alloy it is difficult to separate these two factors. Thus althou copper is highly susceptible to impingement attack its resistance increases with increase in zinc content, with a corresponding increase in hardness. However, the increase in resistance to attack is due to the formation of a more protective him rather than to an increase in hardness. [Pg.192]

Seawater-based utility systems for condenser and process cooling systems in power plants exhibit serious corrosion, erosion and fouling problems. Equipment made from carbon steel and even stainless steel shows sign of degradation from galvanic effect, corrosion, erosion and microbiological induced corrosion (MIC). Corrosion... [Pg.187]

The duplex stainless steels are superior to other stainless steels with respect to high resistance to chloride stress corrosion cracking, high mechanical strength, lower thermal expansion than the austenitic grade steels, and good erosion and wear resistance. [Pg.223]

A stainless steel pump impeller with an expected lifetime of two years failed in three weeks in a reducing solution. Metals that are soft are readily damaged or worn mechanically examples are copper and lead. Even the noble or precious metals, such as silver, gold, platinum, are subject to erosion-corrosion.16,31... [Pg.399]

Galvanic effect. The galvanic cell between two different metals can have serious effects in a flowing system. For example, the galvanic cell was not present between stainless steel type 316 and lead in 10% sulfuric acid under static conditions, but when the flow rate increased to 11.89 m s the rate of erosion-corrosion increased enormously... [Pg.400]

Toughness can influence the performance of materials under conditions of erosion-corrosion. The soft metals are often more susceptible to erosion corrosion because they are more susceptible to mechanical wear. The toughness is a good criterion for the resistance to the mechanical erosion or abrasion, but this is not necessarily a good criterion to predict the resistance to the erosion-corrosion. Stellite (Co-Cr-W-Fe-C alloy), which has better toughness than 18-8 stainless steel, showed better resistance to cavitation erosion on a water brake.25... [Pg.402]

There are several ways to harden alloys. A certain procedure to increase the resistance to the erosion corrosion is the hardening by solid solution. One adds an element to another to produce a solid solution that is resistant to the corrosion by hardening the metal. The thermal treatment is also a method to harden a metal or alloy, but it changes the microstructure and can induce a greater susceptibility to corrosion. Hardening by cold work is also an important procedure and it is the reason for using stainless steel to resist cavitation erosion. This material, initially hard, attains an even harder surface by cold work and becomes more resistant to attack and erosion. [Pg.402]

Another risk is breakage which may occur in plant upsets. For example rapid depressurization could lift the packing. For this reason the material of modern packings is either steel (often stainless steel because of potential erosion/corrosion) or polypropylene. In some processes the variation of the promoter concentration may be a variable in the optimization puzzle, too. [Pg.125]


See other pages where Stainless steels erosion-corrosion is mentioned: [Pg.66]    [Pg.301]    [Pg.361]    [Pg.274]    [Pg.46]    [Pg.787]    [Pg.317]    [Pg.606]    [Pg.96]    [Pg.191]    [Pg.791]    [Pg.70]    [Pg.126]    [Pg.52]    [Pg.95]    [Pg.188]    [Pg.196]    [Pg.483]    [Pg.301]    [Pg.79]    [Pg.269]    [Pg.4]    [Pg.399]    [Pg.79]    [Pg.611]    [Pg.301]   
See also in sourсe #XX -- [ Pg.240 , Pg.249 , Pg.259 ]




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Erosion-corrosion

Stainless steels corrosion

Steel corrosion

Steel erosion-corrosion

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