“Solutions for specialty alloy piping requirements"
Nickel - Monel® - Inconel® - Incoloy® - Hastelloy® - Alloy 20 - Duplex
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“Solutions for specialty alloy piping requirements"
Nickel - Monel® - Inconel® - Incoloy® - Hastelloy® - Alloy 20 - Duplex
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Heat Resistant Alloys Wrought and Cast Material Inconel® 600 Inconel® nickel-chromium-iron alloy 600 is a standard engineering material for applications, which require resistance to corrosion and heat. The alloy also has excellent mechanical properties and presents the desirable combination of high strength and good workability. The high nickel content gives the alloy resistance to corrosion by many organic and inorganic compounds and also makes it virtually immune to chloride-ion stress-corrosion cracking. Chromium confers resistance to sulfur compounds and also provides resistance to oxidizing conditions at high temperatures or in corrosive solutions. The alloy is not precipitation hardenable; it is hardened and strengthened only by cold work. The versatility of Inconel® alloy 600 has led to its use in a variety of applications involving temperatures from cryogenic to above 2000°F. The alloy is used extensively in the chemical industry for its strength and corrosion resistance. Applications include heaters, stills, bubble towers, and condensers for processing of fatting acids; evaporator tubes, tube sheets, and flaking trays for the manufacture of sodium sulfide; and equipment for handling abietic acid in the manufacture of paper pulp. The alloy's strength and oxidation resistance at high temperatures make it useful for many applications in the heat treating industry. It is used for retorts, muffles, roller hearths, and other furnace components and for heat treating baskets and trays. In the aeronautical field, alloy 600 is used for a variety of engine and airframe components, which must withstand high temperatures. Examples are lock wire, exhaust liners, and turbine seals. The alloy is a standard material of construction for nuclear reactors. It has excellent resistance to corrosion by high purity water, and no indication of chloride-ion stress-corrosion cracking in reactor water systems has been detected. For nuclear applications, the alloy is produced to exacting specifications and is designated Inconel® alloy 600T.
Inconel® 601 Inconel® 601 is a general purpose engineering material for applications that require resistance to heat and corrosion. The outstanding characteristic of Inconel® alloy 601 is its resistance to high temperature oxidation. The alloy also has good resistance to aqueous corrosion, has high mechanical strength, and is readily formed, machined and welded. The composition is a face-centered-cubic solid solution with a high degree of metallurgical stability. The alloy's nickel base, in conjunction with a substantial chromium content, provides resistance to many corrosive media and high temperature environments. Oxidation resistance is further enhanced by the aluminum content. The properties of Inconel® 601 make it a material of broad utility in such fields as thermal processing, chemical processing, pollution control, aerospace, and power generation. In industrial furnaces, the alloy is used for radiant tubes, muffles, retorts, flame shields, strand-annealing tubes, woven-wire conveyor belts, chain curtains, burner nozzles, and electrical resistance heating elements. Chemical processing applications for alloy 601 include process heaters, condenser tubes in sour water strippers and insulating cans in ammonia reformers, The alloy is also used for combustor components and catalyst grid supports in equipment for nitric acid production. In petrochemical processing, the alloy is used for catalyst regenerators and air preheaters in the manufacture of high-density polyethylene. In power-generation, alloy 601 is used for super heater tube supports, grid barriers, and ash-handling systems
Inconel® 625 Inconel® nickel chromium alloy 625 is used for its high strength, excellent fabricability (including joining), and outstanding corrosion resistance. Service temperatures range from cryogenic to 1800°F. Strength of Inconel® alloy 625 is derived from the stiffening effect of molybdenum and columbium on its nickel-chromium matrix; thus precipitation-hardening treatments are not required. This combination of elements also is responsible for superior resistance to a wide range of corrosive environments of unusual severity as well as to high-temperature effects such as oxidation and carburization. The outstanding and versatile corrosion resistance of Inconel® alloy 625 under a wide range of temperatures and pressures is a primary reason for its wide acceptance in the chemical processing field. Because of its ease of fabrication, it is made into a variety of components for plant equipment. Its high strength enables it be used, for example, in thinner-walled vessels or tubing than possible with other materials, thus improving heat transfer and saving weight. Some applications requiring the combination of strength and corrosion resistance offered by Inconel® alloy 625 are bubble caps, tubing, reaction vessels, distillation columns, heat exchangers, transfer piping and valves.
Incoloy® Alloy 800 Incoloy® alloy 800 is a widely used material of construction for equipment that must have high strength and resist oxidation, carburization, and other harmful effects of high-temperature exposure. (For high temperature applications requiring optimum creep and rupture properties, Incoloy® alloys 800H and 800HT® are used). The chromium in the alloy imparts resistance to oxidation and corrosion. The high percentage of nickel maintains an austenitic structure so that the alloy is ductile. the nickel content also contributes resistance to scaling, general corrosion, and stress-corrosion cracking. The iron content provides resistance to internal oxidation. Incoloy® alloy 800 is used in a variety of applications involving exposure to corrosive environments and high temperatures. It is used for heat-treating equipment such as baskets, trays and fixtures. In chemical and petrochemical processing the alloy is used for heat exchangers and other piping systems in nitric acid media especially where resistance to chloride stress-corrosion cracking is required. In nuclear power plants, it is used for steam-generator tubing. The alloy is often used in domestic appliances for sheathing of electric heating elements. In the production of paper pulp, digester liquid heaters are often made of alloy 800. In petroleum processing , the alloy is used for heat exchangers that air-cool the process stream.
Incoloy® 800H/800HT® Incoloy® alloys 800H and 800HT® have significantly higher creep and rupture strength than Incoloy® 800. The three alloys have nearly identical chemical composition limits. However, the chemical composition limits vary with carbon, aluminum and titanium. The carbon content of Incoloy® alloy 800 (UNS n08800) is 0.10% max with no limit on the lower end. The carbon content for Incoloy® alloy 800H (UNS N08810) is 0.05% to 0.10% which is the upper end of the 0.10% maximum specified for Incoloy® alloy 800. The chemical limits for Incoloy® 800HT® (UNS08811) are even more restrictive yet still within the limits specified for Incoloy® 800H. The carbon content for Incoloy® alloy 800HT® is further restricted to 0.06%-0.10%. Additionally the Al plus Ti content of Incoloy® alloy 800HT® is restricted to 0.85%-1.20%. Note that the chemical composition for Incoloy® alloy 800HT® will always be within the limits of Incoloy® alloy 800H. Note also that the limits for Incoloy® alloy 800H may or may not be within the limits of Incoloy® alloy 800HT®. In addition to the controlled carbon content, Incoloy® alloys 800H and 800HT® receive a high temperature annealing treatment that produces an average grain size of ASTM 5 or coarser. The annealing treatment and restricted chemical composition are responsible for these alloys having greater creep and rupture strength. The mechanical properties of Incoloy® alloys 800H and 800HT®, combined with their resistance to high temperature corrosion, make these alloys exceptionally useful for many applications involving long-term exposure to elevated temperatures and corrosive atmospheres. In the hydrocarbon processing industry, these alloys are used in steam/hydrocarbon reforming for catalyst tubing convection tubing, pigtails, outlet manifolds, and quenching-system piping; in ethylene production for both convection and cracking tubes, and pigtails; in oxy-alcohol production for tubing in hydrogenation heaters; in hydrodealkylation units for heater tubing; and i the production of vinyl chloride monomer for cracking tubes, return bends and inlet and outlet flanges. Industrial heating is another area of wide usage for both Incoloy® 800H and 800HT®. In various types of heat treating furnaces, these alloys are used for radiant tubes, muffles, retorts, and assorted furnace fixtures. Alloys 800H and 800HT® are also used in power generation for steam superheating tubing and high temperature heat exchangers in gas cooled nuclear reactors.
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