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market in the case of an asbestos ban (Palmetto Packing 1986, ICF l986a). 5. Graphite Flexible graphite was developed by Union Carbide Corp. about twenty years ago. The material is made from natural flake graphite, which is expanded several hundred times into a light, fluffy material by mixing it with nitric or sulfuric acid. It is then calendered into a sheet (without additives or binders) (Chem. Eng. News 1986). It can then be processed into packings by standard techniques. Other forms of graphite are also available (e.g., carbonized viscose rayon and other fibrous graphite materials) that have similar properties. All graphite materials will be grouped together for convenience and because their properties are similar. Graphite materials are extremely heat resistant and inherently fire-safe (because it does not contain binders). Graphite packings are suitable for applications where the operating temperatures reach 5000°Fin non-oxidizing atmospheres. In the presence of oxygen, the material is limited to use below 800°F(Chem. Eng. News 1986). The packinghas excellent chemical resistance with the exception of strong mineral acids. Graphite-containing packings are often used in oil refineries and oil fields because of its high temperature resistance. Often, in these high temperature, high pressure applications, a wire insert is added for increased strength (OGJ 1986). Graphite materials are fairly expensive, but the addition of various fillers helps keep the cost competitive with other substitute materials (Palmetto Packing 1986). Graphite packings cost about two times as much as asbestos packings on a per weight basis and costs are estimated to be $60.40 per pound (Union Carbide 1987). Industry officials project this substitute’s market share as 10 percent of the total asbestos packing market (Palmetto Packing 1986, ICF 1986a). - 17 -
6. Other Substitute Fibers Other fiber products made from cellulose, phosphate, or ceramic fibers have very small market shares and are not seen as viable replacement for asbestos in general service areas at this time. Ceramic fibers have been used for packing materials, but do not see widespread-use due to their abrasive nature and brittleness (Union Carbide 1987). Phosphate fibers may see an increased market share in the future, but currently are only in developmental stages 4 (Monsanto 1987). Cellulose fibers occupy a very limited market share although for applications demanding little in the way of high performance they can be used (ICF l986a). E. Summary It appears that substitutes for asbestos containing packings currently exist. These products, however, cost more to produce and may not perform as well. Since no across the board substitute fiber exists, manufacturers have been forced to replace asbestos with a combination of substitute materials, - including graphite, PTFE, glass, aramid, and FBI fibers. The substitute materials are a combination of fibers and fillers designed on an applicationby-application basis. The materials are classified by the fiber with the highest content. Table 5 summarizes the characteristics of the asbestos substitutes. The estimation of market shares, prices of the substitute formulations in the event of an asbestos ban, and data inputs for the Asbestos Regulatory Cost Model are summarized in Table 6. ~ Although these fibers seem promising there is little industry data on their performance in field applications. - 18 - -
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 and 28: een forced to replace the asbestos
Page 29 and 30: Table 4. Estimated Market Share for
Page 31: useful temperature limit of approxi
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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