Refractories refractoriness

The furnace is constmcted with a steel shell lined with high temperature refractory (see Refractories). Refractory type and thickness are deterrnined by the particular need. Where combustion products include corrosive gases such as sulfur dioxide or hydrogen chloride, furnace shell temperatures are maintained above about 150—180°C to prevent condensation and corrosion on the inside carbon steel surfaces. Where corrosive gases are not present, insulation is sized to maintain a shell temperature below 60°C to protect personnel. 

Plastics Society of the Plastics Industry 355 Lexington Avenue New York, NY 10017 Refractories Refractories Institute Suite 1517 301 Fifth Avenue Pittsburgh, Pa. 15222... 

C. W. Hardy and co-workers. Committee on Technology—Special Study Team on Refractories, Refractory Materials for Steelmaking International Iron and Steel Institute, Bmssels, Belgium, 1985. 

Forsterite Refractories. Refractories made from forsterite, Mg2Si04, resist alkah attack and have good volume stabiUty, high temperature strength, and fak resistance to basic slags. Uses include nonferrous metal furnace roofs and glass-tank refractories not in contact with the melt, ie, checkers, ports, and uptakes. 

Interstitial Compounds. Tungsten forms hard, refractory, and chemically stable interstitial compounds with nonmetals, particularly C, N, B, and Si. These compounds are used in cutting tools, stmctural elements of kilns, gas turbines, jet engines, sandblast nozzles, protective coatings, etc (see also Refractories Refractory coatings). 

Cemented carbides belong to a class of hard, wear-resistant, refractory materials ia which the hard carbides of Group 4—6 (IVB—VIB) metals are bound together or cemented by a soft and ductile metal biader, usually cobalt or nickel. Although the term cemented carbide is widely used ia the United States, these materials are better known iatemationally as hard metals (see also Refractories Refractory coatings Refractory fibers). 

Refractories Refractories are selected to accomplish four objectives ... 

Refractoriness. Refractoriness is determined by several methods. The pyrometric cone equivalent (PCE) test (ASTM C24) measures the softening temperature of refractory materials. Inclined trigonal pyramids (cones) are formed from finely ground materials, set on a base, and heated at a specific rate. The time and temperature (heat treatment) required to cause the cone to bend over and touch the base is compared to that for standard cones. 

Cnthidia fasciculata - [SILICA - INTRODUCTION] (Vol21) - [CLAYS - SURVEY] (Vol 6) - [SILICA - SYNTHETIC QUARTZ CRYSTALS] (Vol 21) - [GLASS] (Vol 12) -from diatomite piATOMITE] (Vol 8) -OSHA specifications [ABRASIVES] (Vol 1) -m silica refractories [REFRACTORIES] (Vol 21) - [ANTIBIOTICS - ANSAMACROLIDES] (Vol 2)... 

REFRACTORIES. Refractories are materials that resist the action of hot environments by containing heat energy and hot or molten materials, There is no well-established hue of demarcation between those materials that are and those that are not refractory. The ability to withstand temperatures above 1100°C without softening has, however, been cited as a practical requirement of industrial refractory materials. (See also Ceramics), The type of refractories used in any particular application depends on the critical requirements of the process. 

Refractoriness. Refractoriness is the resistance to physical deformation under the influence of temperature. It is determined by the pvrometnc cone equivalent (PCE) test for aluminosilicates and resistance to creep or shear at high temperature. 

Graphite is also used as a refractory. Refractory material can withstand very high temperatures by reflecting heat away from itself Refractory materials are used to line ovens to maintain high temperatures. 

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