Foundry cores

Fossil copal Fossil flour Fossil-fuel furnaces Fossil fuel prices Fossil fuels Fotoform/Fotoceram Fougere Royal Foundry alloys Foundry core binders Foundry furnaces Foundry resins Fountains Fourcault process... 

Dryings of Castings and Other Products. The use of microwaves in the curing and drying of foundry cores is weU estabhshed (185). The best example is the use of microwaves for drying water-based core washes at 2450 MHz with up to 150 kW. These apphcations have not, however, found apphcation in manufacturing. Many similar drying apphcations have been examined (186,187). 

Other uses for coal-tar pitch include production as a binder for foundry cores, as a sealant for dry batteries, and in the manufacture of clay pigeons. PeUeted pitch used as the binder in foundry cores is a hard pitch suppHed as spherical granules which are formed by a spray-cooling process. Clay pigeons consist of disks molded from a mixture of hard pitch and a mineral filler such as clay or limestone dust. 

Water-borne adhesives are preferred because of restrictions on the use of solvents. Low viscosity prepolymers are emulsified in water, followed by chain extension with water-soluble glycols or diamines. As cross-linker PMDI can be used, which has a shelf life of 5 to 6 h in water. Water-borne polyurethane coatings are used for vacuum forming of PVC sheeting to ABS shells in automotive interior door panels, for the lamination of ABS/PVC film to treated polypropylene foam for use in automotive instmment panels, as metal primers for steering wheels, in flexible packaging lamination, as shoe sole adhesive, and as tie coats for polyurethane-coated fabrics. PMDI is also used as a binder for reconstituted wood products and as a foundry core binder. 

Foundry core oil. CNSL resins are known to impart good scratch hardness to sand core after they are baked [133,134,137,167]. It also provided resistance to moisture and weathering and good green strength, and surface finish to molded articles. 

Metal foundries (core-making) IV-nitrosodimethylamine (NDMA) >5... 

Uses. Solvent for cellulose ethers, esters, resins, and dyes liquid propellant binder in foundry cores manufacture of resins including furfuryl alcohol resin (furan resin) and furfuryl alcohol-formaldehyde resins... 

Workers exposed to 8.6 and 10.8 ppm in a foundry core-making operation experienced no discomfort, but two persons exposed to 15.8 ppm (and 0.33 ppm formaldehyde) experienced lacrimation and a desire to leave the area. In another foundry core-making operation, no ill effects were seen after exposures of about 6-16 ppm. ... 

Carbon pitch is used for carbon electrodes in electrolytic reduction processes, such as aluminum reduction or the production of electro-steels in arc furnaces. Refractory pitch is used in the manufacture of refractory brick, usually burned magnesite or dolomite, the pores of which are filled with pitch by hot impregnation. Upon firing, the pitch in the brick is converted to carbon by carbonization. The remaining pitch coke within the refractory product retards penetration of molten metals and slags, thus prolonging the life of the brick furnace lining. Coke pitch is used in the production of foundry cores. 

Most furfural is produced from corncobs and oat and rice hulls, primarily by the Quaker Oats Company. The product is used in the chemical industry as a solvent and in wood rosin refining. A large amount of furfural is treated further to give furfuryl alcohol. The furfuryl alcohol is added to urea-formaldehyde resins in applications for adhesives and foundry core binders. 

Use Binder for carbon electrodes, base for paints and coatings. Impregnation of fiber pipe for electrical conduits and drainage, foundry core compounds, briquetting coal, tar-bonded refractory brick, paving and roofing, plasticizers for elastomers and polymers, extenders, saturants, impregnants, sealants. 

Use Wetting agent, furan polymers, corrosion-resistant sealants and cements, foundry cores, modified urea-formaldehyde polymers, penetrant, solvent for dyes and resins, flavoring. The polymer is used as a mortar for bonding acid-proof brick and chemical masonry. 

Use Scale housings, dinnerware, interior plywood, foundry core binder, flexible foams, insulation. 

Use Source of zirconium oxide, metallic zirconium, and hafnium abrasive refractories enamels refractory porcelain catalyst silicone rubbers foundry cores. 

The viscosity of caramel allows its employment as an adhesive and binder for instant sand-molds and foundry core for producing difiicultly accessible, hollow cavities in castings. Caramel binds together a sodium chloride, quartz, or metal-powder matrix to a mass that binds to aluminum or aluminum-alloy castings. On casting, such a binder produces only a small volume of combustion gases. The cores are readily removed, either mechanically or by dissolution. ... 

Unmodified urea-formaldehyde resins are unsuitable for use in surface coatings formulations, due to their lack of solubility in common solvents and incompatibility with other resins. This limitation can be substantially overcome when the resins are modified by alcohols, such as n-butanol. Very commonly, butylated urea-formaldehyde resins are blended with alkyd resins to provide good flexibility and adhesion in coatings. Furfuryl alcohol-modified urea resins are used to bind foundry cores formed in preheated pattern boxes, due to their capability of rapid core production. 

Many efforts have been made to base polymers on furfural made from pentoses.159 The polymers may be useful, but tend to have lower thermal stability than the usual synthetic polymers. Polyesters based on furfural were mentioned earlier. The acid-catalyzed polymerization of furfuryl alcohol is used in foundry cores.160 Furfural has been condensed with cardanol (m-pentadecadienylphenol) from cashew nut shell oil in the presence of other phenols to produce polymeric resins.161 Cardanol and hydrogenated cardanol have been polymerized with horseradish peroxidase to soluble polymers in up to 85% yield.162 Plasticizers that are effective in polyvinyl chloride, such as (12.31), have been made from furfural.163... 

The use of polyurethane as a binder has found two interesting applications foundry cores and woodchip particleboard. The foundry industry has recognized the value of polyurethane adhesive binders to bind sand foundry cores for metal casting. This application is increasing steadily. The use of isocyanate binders for woodchip particleboard is receiving significant attention. The... 

Adhesives and sealants, foundry core binders, Spandex fibers, thermoplastic polyurethanes. 

Chem-Rez . (Ashland/Foundry Prods.] Resin foundry core binders. 

Ecoset [Ashland/Foundty Pir. ] Ina-ganic foundry core binders. 

Indnctoid. [AsUand/Foundry Prods.] Foundry core oils. 

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