Plastic refractories

Plastic Refractories and Ramming Mixes. Plastic refractories are mixtures of refractory grains and plastic clays or plasticizers with water. Ramming mixes may or may not contain clay and are generally used with forms or steel work. The amount of water used in these products varies but is held to a minimum to faciUtate drying. Plastics are generally suppHed in a ready-to-use state. 

Plastic pellets, threat from, 20 231 Plastic pumps, for corrosive liquids, 21 76 Plastic refractories, 21 482 Plastics. See also Styrene plastics adhesion of coatings to, 7 91-92 advanced materials, 1 693 cellulose ester applications, 5 404 chemical exposure tests on, 19 583 citric acid application, 6 648 colloidal suspensions, 7 273t colorants for, 7 358-380 development of, 10 168... 

Other common refractory forms include setter tile and kiln furniture, fusion-cast shapes, cast and hand-molded refractories, insulating refractories. castables and gunning mixes, plastic refractories and ramming mixes, mortars, composite refractories, and refractory coatings,... 

Plastic Refractory Clays.—Clays combining good plasticity with high refractoriness are not of common occurrence. While there are a number of such deposits in the United States, the majority of these materials show plasticity at the expense of heat-resisting power, that is, they soften at temperatures below that of cone 32. Occasionally they develop in limited quantities as the result of the weathering of flint clay. 

At this time, 1977-1978, it appears that the current best boiler-furnace design in use for large, high pressure units is the completely water-tube-walled furnace and radiant section, studded and coated with thin plastic refractory in the intense burning zone, followed by one or more long, open, vertical radiation passes preceding a convention-type superheater and boiler-convection passes and economizer. 

Emerald Ram HS. [Premier Refractories] Alumina chrome plastic refractory. 

At the ends of the heaters, tubesheets are provided through which the tubes pass outside the combustion chamber to a header compartment. Tubesheets are generally cast iron with plastic refractory facing on the fire side in sections holding five or six tubes and are bolted to the... 

Plastic refractories contain a binder material, and are tempered with water so that they have suitable plasticity for pounding or ramming into place. 

With any material used in high-temperature applications, the effect of linear thermal expansion, and especially the permanent linear change, must be considered. Shrinkage of castables is less than that of plastic refractories therefore, permanent linear change is less. Castable refractories are significantly superior to firebrick in permeability resistance and spalling resistance. Plastic refractories have better spalling resistance than either firebrick or castables. 

Uses Reducing agent purifying metals electronics filler in rubber compds., coatings, and plastics refractories furnace linings electrodes fibers... 

Trixylenyl phosphate Undecyl dodecyl phthalate Undecyl phthalate plasticizer, PVC cable compounds Diisononyl phthalate plasticizer, PVC film Di (C7-9 alkyl) adipate plasticizer, PVC flexible blends Di-n-C6-C10-alkyl phthalate plasticizer, PVC flooring Butyl benzyl phthalate plasticizer, PVC foam Tris (2,3-dichloropropyl) phosphate plasticizer, PVC plastisols Butyl benzyl phthalate Di (C7-9 alkyl) adipate Di-n-C8-C10-alkyl phthalate plasticizer, PVC wire/cable insulation Trixylenyl phosphate plasticizer, PVC fire-resistant Tris (isopropylphenyl) phosphate plasticizer, PVC PE sealants Chlorinated paraffins (Cl2, 60% chlorine) Chlorinated paraffins (C23, 43% chlorine) plasticizer, raincoats Dioctyl azelate plasticizer, refractory Methylcellulose plasticizer, refractory shapes Hydroxypropyl methylcellulose plasticizer, regenerated cellulose film Glycerin... 

Air-setting mortars using clay and phosphates were obtained in 1952 [21]. Mortars can be made from calcined bauxite mixed with a little clay (80%) and aqueous phosphoric acid (20%). A good refractory mortar can be obtained from an aqueous mix of 92% kaolin with 8% A1(H2P04)3. Another air-setting plastic refractory mortar can be obtained from 75% alumina, 20% clay and 5% A1(H2P04)3 [22]. 

ASTM C-181 Workability index of fireclay and high-alumina plastic refractories... 

Berg Method. See diver method. Berkeley Clay. A plastic, refractory kaolin from S. Carolina P.C.E.34. Berkovich Indenter. A 3-faced diamond pyramid for indentation hardness tests. 

Bottger Ware. A dark red stoneware. Bolting Clay. Prepared plastic refractory material for use in the stopping of the tap-holes in cupolas. A typical composition would be 50-75% fireclay, up to 50% black sand, 10% coal dust and up to 5% sawdust. 

Fireclay Plastic Refractory. A US term defined as A fireclay material tempered with water and suitable for ramming into place to form a monolithic furnace lining that will attain satisfactory physical properties when subjected to the heat of furnace operation. 

Flint Clay. A non-plastic refractory clay of a type found in Missouri (USA), Southern France, and a few other localities. Flint clays are kaolinitic, but laterization (See laterite) has occurred so that the Missouri deposit, for example, may also contain diaspore whereas the French may contain boehmite. Flint clays contain (fired) 40-45% AI2O3 P.C.E. 34-35. 

Plastic Refractory. ASTM C71 defines this as a refractory material, tempered with water, that can be extruded and that has suitable workability to be pounded into place to form a monolithic structure. See fireclay plastic... 

Super-duty Fireclay Refractory. Defined in ASTM - C27 as a fireclay brick having a P.C.E. 33 and an after-contraction 1% when tested at 1600 C. There are three types Regular, Spall Resistant, Slag Resistant. Limits are set for panel spalling loss, modulus of rupture and bulk density. ASTM C-673 specifies a super-duty plastic refractory with P.C.E. 321/. ... 

Monolithic linings are a relatively recent development and consist of unshaped refractory products [3]. There are two basic types of monolithic linings castable refractory and plastic refractory. 

In the aluminum industry, melting furnaces are made entirely out of monolithic refractories. The heating chamber is lined with high-alumina castable, while sections that are in direct contact with the metal are made from phosphate-bonded plastic refractory. 

Initially, when unshaped refractories were first used, the property requirement was kept the same as for shaped refractories, in thatthey mainly replaced linings. Later on, when the use of these refractories became widespread, new standards had to be developed. The first standards on unshaped refractories by the American Society for Testing of Metals (ASTM) were published in 1943 [3]. They were numbered as C 179 and C 181 C 179 covered "drying and firing linear change of plastics and rammings" and C 181 dealt with "workability index of plastic refractories." As noted earlier. World War II saw an increase of about 35% in unshaped refractory production. Specifications were required to obtain the required items from many manufacturers. 

Plastic Refractory Materials Plastic refractory materials are the oldest monolithic material. They were developed as pliable firebrick in the United States in 1914 and were used a long time as the front part of many furnaces [3]. These are supplied in moldable, preformed blocks and placed by ramming. They harden under heat. 

Ramming is performed on plastic refractory materials and on refractory ramming mixes. 

Castable and plastic refractories are the two types of liners most commonly used. The plastic varieties incorporate phosphate as a chemical bond-... 

After the inventions of the plastic refractory in 1914 and the cast -able refractory in 1923, in the United States, there was a long pause until the mid-1950s, when the conventional gunning technology was established in Europe, too. As far as prefabricated shapes are concerned, the original idea was to make big prefabricated and pretreated blocks for quick installations and short heat-up times. The time of prosperity for this way of thinking was in the... 

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