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

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according to ASTM D 299, the standard for such materials. These grades are listed in Table 1 (ASTM 1982). The dimensions of the packing are controlled by the size and number of yarns selected (Kirk-Othmer 1981). Another type of braided packing, braid-over-braid packing, consists of individually braided jackets layered over a core. These packings use wire-inserted yarns that offer greater strength to the packing material. Rolled compression packings are constructed of woven cloth that is coated with a rubber binder and then cut in strips along the bias to impart maximum cloth stretch during forming. The rubber-saturated strips are wound around a soft rubber core and then formed into the desired final shape. The final cutting, forming, and compression operations for all packing types are usually performed by secondary processors (FSA l983).1 All of the packing formation processes have some characteristics in common. First, impregnation of dry asbestos yarn with a lubricant. After lubricant impregnation, the yarns are braided into a continuous length of packing which in turn is calendered to a specific size and cross-sectional shape. The formed product may then be coated with more lubricant or another material. At this stage packings can be packaged and sold for maintenance operations or they can be further processed by pressing into the required shape (GCA 1980). Finally, packings can be die-formed directly into solid rings to facilitate handling and installation. The packings that have been formed into a designated shape are referred to as plastic packings (Kirk-Othmer 1981). The uses and applications of asbestos packings are quite varied, but some of the major areas in which asbestos-containing packing materials have been 1 Secondary processing usually occurs at the facility where the gaskets will be used and consists of cutting and compressing the packings as they are needed to replace worn packings already in service in various pumps, valves, etc. -3-
Table 1. Standards of Asbestos Yarns Used in Asbestos Packings Grade Asbestos Content (percent) Commercial Underwriters’ A AA AAA AAAA 75-80 80-85 85-90 90-95 95-99 99-100 Source: ASTM 1982. -4-
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: Bulk Square braád Rolled (over cor
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 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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