Document vB99Mer8Zyj37g6E4EnNXKv96

r:;OM D. D. MC GREGOR PRIMARY METALS DIVISION PITTSBURGH OFFICE - 23 TO MR. G. E. GRADDY ALCOA TECH. CENTER 1981 March 20 STING OF CATHODE MATERIALS Confirming discussions at the 1981 March 19 HPTF meeting, please contact the following plants to obtain representative cathode block samples for sodium intercalation tests: (Sufficient samples for Dr. Belitskus" work should be included along with yours. Please coordinate with him.) Badin Tennessee Vancouver - Locally manufactured block Locally manufactured block Alcan cathode block Midwest cathode block In addition, you will make longer term (than the 24-hour) tests of insulation materials in a bath environment. Among those to be included are: Superex 2000 IV-20 IV-19 Keene Monoblock . (Such others as you and Mr. Caprio select) Representative samples can be obtained from various plants, or Mr. Caprio can obtain them from vendors. You are requested to arrange for these samples. For plants' and Mr. Caprio's information, further testing has shown no significant difference between Superex 2000, IV-20, or IV-19 with regard to bath attack in a 24-hour laboratory test. Our current recommendations to plants, from the HPTF discussions, are to install a minimum of 10 pots and a maximum of 20 pots, using IV-19 in both bottom and sides. Keene Monoblock also presents no significant personnel hazard and is approved for use in sides only. It should not be used in bottoms, due to extremely low compressive strength. Dr. Fisher will run bottom heat loss surveys on the 6 Massena pots installed with IV-19 bottoms - along with 6 control pots. At the fall HPTF meeting, this subject will be reviewed and plants' experience discussed. D. D. MC GREGOR DDM:mfq cc: See page 2 APC 003928 Mr. G. E. Graddy 1981 March 20 Page 2 cc: M. B. Dell - ATC-C l D. L. Belitskus - ATC-C \ M. Caprio - Pittsburgh (19) S. C. Jacobs - Pittsburgh (23) L. A. Hartley - Badin Works B. M. Triko - Massena Operations D. A. Nelsen - Pt. Comfort Operations E. B. Colley - Pt. Comfort Operations G. H. Lantz - Rockdale Works G. A. Turnbow - Tennessee Oprns. (South Plant) P. C. Ames - Vancouver Operations D. J. Carney - Warrick Operations M. H. Johnson - Wenatchee Works I. B. Beaumont - Pt. Henry Works R. J. Leser - Veracruz Works, Mexico N. L. Sundaram - Paranam Operations APC 003929 D. D. McGREGOR PRIMARY METALS DIVISION PITTSBURGH OFFICE TO MR. V^D. GRISWOLD WARRICK OPERATIONS 1981 March 23 RE: POTLINING INSULATION IV-19 & IV-20 Reference your letter dated 81/02/11, same subject. Further testing at ATC of captioned and other materials reveal no significant differences in resistance to bath cutback. IV-20 and Superex 2000 appear to be equivalent materials in regard to physical characteristics and both contain crystoballite, a form of respirable silicon. People handling these materials should wear appropriate masks. IV-19 and Keene monoblock present no serious handling problems insofar as we know. These materials are currently recommended in the lower sides where many of our plants must cut insylation to fit. Further and more extensive tests are planned. At the HPTF meeting in 1981 March, it was recommended that all plants install 10 to 20 pots using IV-19 throughout as insulation (bottom and sides). At the fall HPTF meeting, the further testing and plant experience, including heat loss test results from 6 pots currently Installed at Massena, along with control pots, will be reviewed. In summary, Warrick should not standardize on IV-19 as proposed, but should continue to use IV-20 or Superex 2000 In bottoms. Either IV-19 or Keene monoblock can currently be used where cutting is required. D. D. McGREGOR .DDM:skm \ REVIVED PURCHASING APC 003930