Gaskets are materials used to seal one compartment of a device ...

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about twenty times more expensive than asbestos, by weight, but because they are less dense and stronger, less is needed for reinforcement purposes. At higher temperatures, the fibers physically degrade and thus are not good replacements for asbestos products for high temperature applications. Aramid packings are usually 20 percent aramid fiber, by weight, and 60 to 65 percent filler, while the remaining 20 to 25 percent is binder to keep the fibers in a matrix. Typical applications for valves and pumps require a very strong packing material that will withstand moderate temperatures and pressures without deteriorating. Raymark Corporation, in Stratford, CT, was the only asbestos packing manufacturer to cite aramid packings as a substitute for asbestos products. They can be used for general service in most plants (A.W. Chesterton 1983). Aramid-based products are likely to be 1.5 to 3 times as expensive as the asbestos products they replace, therefore aramid packings cost between $45.30 and $90.60 per pound. The price increase is due to production and material cost increases (ICF l986a). There are no performance disadvantages due to the dilution of the aramid fiber with mineral fillers and this helps to reduce the price of packings. The service life is estimated to be the same as the life of the asbestos product. Industry estimates indicate that aramid products will capture 20 percent of the total packings market. The average price for an aramid-based packing is estimated to be $67.95 per pound (ICF l986a, Palmetto Packing 1986). 2. Fibrous Glass Mixtures Fibrous glass is generally coated with a binder such as neoprene, TFE, or graphite in the manufacturing process to make packings. Glass fibers are relatively easy to process into packing materials and are used extensively in packing materials. - 13 -
Table 4. Estimated Market Share for Substitute Fibers that can Replace Existing Asbestos Products in Compression Packings Substitute Fiber Market Share (percent) Reference Glass 30 Palmetto Packing 1986 Graphite 10 Union Carbide 1987 Aramids 30 ICF 1986a PBI 15 ICF 1986a PTFE 15 Union Carbide 1987 NOTE: The market shares indicated are estimates based on communications with industry representatives and are likely to change over time. For example, the share of graphite products is likely to increase over the next five years. New products (e.g., phosphate based fibers) are likely to penetrate the market to a certain extent (Monsanto 1987). - 14 -
Page 1 and 2: XXVII. SHEET GASKETS A. Product Des
Page 3 and 4: Table 1. Fluid and Pressure Ranges
Page 5 and 6: $20.5 million in 1985, based on an
Page 7 and 8: Table 3. Substitutes for Asbestos S
Page 9 and 10: Aramid gaskets are usually composed
Page 11 and 12: esistance. A wire insert is often a
Page 13 and 14: 6. Ceramic Fiber Mixtures Ceramic f
Page 15 and 16: REFERENCES Carborundum. 1986. Produ
Page 17 and 18: Bulk Square braád Rolled (over cor
Page 19 and 20: Table 1. Standards of Asbestos Yarn
Page 21 and 22: A. ‘I’ A. ‘-I PRESSURE ~ Movi
Page 23 and 24: Table 2. Operating Conditions and U
Page 25 and 26: Table 3. Production of Asbestos Pac
Page 27: een forced to replace the asbestos
Page 31 and 32: useful temperature limit of approxi
Page 33 and 34: 6. Other Substitute Fibers Other fi
Page 35 and 36: Table 6. Data Inputs for Asbestos R
Page 37 and 38: TSCA Section 8(a) submission. 1982.
Page 39 and 40: a viscosity control for waterproofi
Page 41 and 42: Table 1. Production of Asbestos Roo
Page 43 and 44: or talc. The additives ease grindin
Page 45 and 46: Table 2. Manufacturers of Cellulose
Page 47 and 48: Cellulose bodied roof coatings and
Page 49 and 50: equivalent basis, they are favored
Page 51 and 52: compounds. These formulations have,
Page 53 and 54: . Other Roof Coatings and Cements O
Page 55 and 56: Table 4. Data Inputs for Asbestos R
Page 57 and 58: ATTACHMENT B PROJECTED PRICES ANALY
Page 59: ICF Incorporated. 1986 (July-Decemb

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