Document 9J7zv2GLa08KzbxVxbqZm9a0V

FROM MICHAEL J. VAUDREUIL PITTSBURGH OFFICE TO L. L. Haisch Vancouver Work3 INDUSTRIAL HYGIENE CONTACTS - As pare of Alcoa's asbestos replacement program, a listing of applications and substitutes for asbestos was compiled and distributed in August of 1979. Since that time, some headway has been made in the development of substitutes for several uses of asbestos. The progress to date is reviewed in the attached memorandum. An updated version of the original master listing is in preparation. Distribution of the revised registry is planned for 1980 November 01. However, critical to this effort is additional input from all Alcoa . locations. Information on current plant asbestos use, as well as any successes (or failures) with substitute materials is requested. In order to meet the November 01 target date for release of the updated list, replies should be received by 1980 October 01. This ongoing exchange of information is necessary for the continued success of the program. With the assignment of Haig Sakoian as Senior Industrial Hygienist, Tennessee Operations, I have assumed the responsibility for overall coordination of the asbestos replacement program. Therefore, please direct all future correspondence to my attention. MICHAEL J. VAUDREUIL MJV:mlf Distribution: Location Managers - Domestic & Caribbean Location Managers - Subsidiaries & Allied Products Safety Managers - Domestic & Caribbean Safety Managers - Subsidiaries & Allied Products Location Engineering Managers Purchasing Agents J. H. Sloane - Pgh. K. W. Perry - Pgh. R. W. Wrenn - Pgh. T. W. Callaham - ATC T. J. Sherman - Pgh. E. B. Perry - Pgh. L. C. Drapela - Pgh. R. N. Sater - Pgh. F. J. McGrath - Pgh. R. C. McCormack 0ALCOAT. I. Stephenson G. F. T.pvmftisrer * - Pgh. - Pgh. - Pgh. ARCH 020013 INDUSTRIAL HYGIENE CONTACTS - DOMESTIC S FOREIGN 1980 August 14 Page 2 Distribution (con't): Industrial Hygiene Mailing List Environmental Managers E. L. Rooy - Pgh. J. Z. Nelson - Pgh. G. F. Stephens - Pgh. D. D. McGregor - Pgh. R. L. Graves - Pgh. M. J. Caprio - Pgh. J. M. McCollum - Pgh. D. St . Jacques - ATC cc: T. B. Bonney, Pittsburgh Office - 7 E. E. Rumberger, Pittsburgh Office - 7 V. ,L. Hammersmith, ATC-B V. W. Rieke, Pittsburgh Office - 2 R. M. James, Pittsburgh Office - 7 R. W. Flanagan, Pittsburgh Office - 6 C. Dixon, Pittsburgh Office - 6 P. H. Scott, Pittsburgh Office - 6 B. L. Siceloff, Pittsburgh Office - 6 Attachments ARCH 020014 FROM MICHAEL J. VAUDREUIL PITTSBURGH OFFICE TO MEMORANDUM 1980 August 14 RE; ASBESTOS REPLACEMENT UPDATE The following sections summarize the progress made over the past year in the search for asbestos substitute materials. The discussions are organized by asbestos product, and within each section by specific application. A supplemental list of substitute material suppliers is included. 1. Molten Metal Marinite . There is presently only one necessary use for asbestos in ingot plant operations; that is, header-applications; There are adequate replacements in Johns-Manville's Marinite I and Pyrotek's Pyrothenn B-2 board products and R-680 for all other melting and casting needs. Therefore, Molten Metal Marinite need not, and should not be used for dams, basins, troughs, etc. However, at present, the suitability of substitute materials for use as floats is questionable. Some header-related applications of asbestos have also been eliminated. After header design modifications, R-680 can be used for all FDC headers 635 mm (25 in.) and smaller. With this substitution, Lafayette, Vancouver and Massena should be asbestos free. Molten Metal Marinite must still be used for HDC and tool and jig headers. R&D programs at ATC will continue to address these areas. 2. Asbestos Rope Fiberseal A-l rope (Pyrotek, Inc.) can be used in place of asbestos rope for sealing the gap between the mold and bottom block in FDC casting operations. It prevents metal leakage and its good thermal stability allows it to be reused numerous times. It may also be used for sealing joints in pouring troughs. Z-5 treated fiberglass rope (Pyrotek, Inc.) can be used successfully as a crucible lid gasket on vacuum-type potroom tapping crucibles. It replaces the presently used Johns-Manville 872 or 702 asbestos gasketing material. However, Z-5 will not replace gaskets made of twisted aluminum foil. Plants using foil gaskets will in all probability have to continue that practice. 3. Transite Transite, a structural, fire-retardant asbestos/portland cement board, is used extensively in construction. ATC has tested glass-reinforced cement (GRC) sheet as a replacement for transite. 3 ALCOA ARCH 020015 MEMORANDUM Page 2 1980 August 14 Although GRC boards are not suitable for high temperatures (>320C) or molten metal contact, they can be used in fire resistant components, pipe work, furnace shells, etc. Physical properties are similar to transite except that GRC board has lower shear strength. However, proper engineering design can compensate for this deficiency. 4. Thermocouple Insulation Finding a suitable replacement for asbestos-coated thermocouple wire has been particularly troublesome. Many substitutes have been rejected because of low abrasion resistance and/or friability at high temperatures. A new ceramic fiber product from 3M, Nextel 312, purportedly exhibits excellent abrasion resistance and immunity'to- thermal-shock. The attached brochure provides more complete product information. If physical properties of Nextel 312 are as claimed, it should prove to be a suitable substitute for asbestos coated wire. Comments and additions to the information presented are encouraged. ARCH 020016 SUPPLEMENTAL SUPPLIES LIST Product Next el 312TM (ceramic fiber) TM Zetex (a.k.a. Pyrotex ; ThermoglassTH (fiberglass) HI FibeR (coated polyethylene fibers) Available Forms Supplier Phone No. 1. woven fabric Ceramic Fiber and tape Products/3M 2. braided sleeving 219-1 3M Center 3. bulk fiber St. Paul, HN 55101 612/733-1558 1. woven fabric Newtex Industries Railroad Avenue P. 0. Box 25 Victor, NY 14564 716/924-9135 1. twisted rope Amatex Corp. 2. braided sleeving 1032 Stanbridge St. 3. woven fabric Norristown, PA 19404 and tape 215/277-6100 1. fiber fillers for cement. caulkings, etc. Hill Bros. Chemical Co. One City Boulevard Suite 1521 Orange, CA 92668 714/634-3322 Celiox Fibers (polyacrylonitrile) *heat treatment 1. fabrics *2. conversion to pure carbon fibers Celanese Plastics 6 Specialities Co. 26 Main Street Chatham, NY 07928 201/635-2600 CER-WOOL (ceramic fiber) 1. blankets 2. vacuum-formed boards 3. bulk fiber C. E. Refractories P. 0. Box 828 Valley Forge, PA 19482 412/351-4409 Siltemp (fibrous glass) 1. cloth Haveg Industries, Inc. 900 Greenback Road Wilmington, DE 19808 1-800-441-7777 GRC Sheet (fiberglass reinforced cement) 1. flat and corrugated board GRC Products, Inc. 17051 I.H. 35N Schertz, TX 78154 512/651-6773 GRC Sheet (fiberglass reinforced cement) 1. flat and corrugated board CEM-FIL Corporation 120 Spence Lane Nashville, TN 37210 615/883-7563 _ tm Preox 1. woven fabric (polyacrylonitrile fiber) Gentex Corporation Carbondale, PA 18407 717/282-3550 ,,Ke,lvartm ^ and Nomex (aramid fiber) 1. cloth E.I. duPont de Nemours 302/999-4693 2. rope & Co. 3. pump packings Textile Fibers Department 4. tapes and Wilmington, DE 19898 webbings 5. braided sleeving MICHAEL J. VAUDREUILtmlf 80-08-05 ARCH 020017 Thermocouple Insulation At last: a practical high-temperature insulating material that eliminates the two biggest causes of thermocouple failure. Dimensional stability and abrasion resis performed 400 per cent better. The figures tance have always been big sources of for 1500 F. and 2000 F were 300 per cent trouble for high-temperature insulators and 166 per cent respectively. The most commonly used fibers- those made from vitreous silica typically shrink, abrade, fray, or crumble to the point where No residual acids or chlorides to cause etching of wires. wires become exposed This obviously Because Nextel 312 Ceramic Fibers con creates a potential for inaccurate tempera ture readings. The traditional alternative, tain no residual acids or chlorides, there's no chemical present to corrode or etch the ceramic beads, solves the problem of ex wires. Even in a test involving exposure cessive shnnkage and abrasion but only to 96 percent relative humidity, no notice at a high cost for labor. able electrolytic corrosion was detected. Now there s a better alternative Nextel' 312 Ceramic Fiber from 3M Nextel 312 withstands operating temperatures of 1000* F. to 2600* F. continuously. It shrinks less and resists the combined effects of abrasion, flexing, and high temperatures better than asbestos, quartz, and vitreous silica fibers. It also offers good chemical resistance and immunity to thermal shock i i I The test consisted of putting Nextel 312 fibers in contact with two unconnected bare #32 copper wires A 250-volt D.C. po tential was applied across the wires. After 20 hours, corrosion was determined by calculating the ratio of anode wire tensile uNextel 312 braided around a thermo- couple wire and heated at 2000* F. for v2 hour shrank ;% Vitreous silica handled the same way shrank 12%. strength to cathode wire tensile strength. Three lest runs produced ratios above 0.99: since the maximum ratio possible was 1.00. there was essentially no elec Proven dimensional stability. trolytic corrosion A recent test compared the dimensional stability of Nextel 312 and vitreous silica by heating sleeves braided around separate lengths of wire for v2 hour at 2000 F When the samples were removed from the fur nace. Nextel 312 still covered the wire completely, thanks to shrinkage of less than 1 per cent. The vitreous silica liber had shrunken by roughly 12 percent, leav ing an inch ol wire exposed at one end Exceptional resistance to abrasion. In another test, a Duplan silk-testing ma chine" was used to compare filaments of Nextel 312 and vitreous silica. Blades were rubbed back and torth on the two products after they had been heated for 'i hour at 1000* F. 1500 F. and 2000 F. Results showed that Nextel 312 lasted 2'i to 5 times as long as the vitreous silica fiber This means that at 1000* F Nextel 312 Available from your local thermocouple supplier. Nextel 312 is being manufactured in pro duction quantities right now. For more information on how it can increase the ser vice life of your thermocouples, contact your supplier Or call 3M at 612-733-1556 (in Northeast locations call 201-575-2076) or write 3M at the address below. -"BII -1<I1.5 ) I I Ceramic Fiber Products/3M 219-1 3M Center St Paul. Minnesota 55101 MTMOMUSA ARCH 020018