Document wq9vgmVgBNgR0xde5QjYxdK6B

FOSECO, INC INTER-COMPANY AND INTER-DEPARTMENTAL CORRESPONDENCE' T0: Distribution Below C. H. FitzGerald trom: Quality Control - S`lPDJ DATE: May 1973 / suejecT: Non-Asbestos Task Force Critique of Production Test - Tuesday, 5/S/73 Activity: S/8/73, 1st shift, K-4, EP S273C (a S273 type recipe using no benconice and resin flocculated with MS366.) 1. Started at 8:10 a.m. Could not fora good edge detail, surface texture very poor. Began to have dewater problems. 2. Reduced fibreglass content - no improvement. 3. Replaced diatomite (1790)- with veraiculite to improve suspension. No improvement-- formed boards began to delayer, still not de watering properly. 4. Added bentonite via pulper - no improvement. 5. Dewater valve diaphragm was found to be defective and replaced. Forming problem not corrected. 6. Drained blow tank and holding-- solids had settled out. Solids were not segregated components but rather dewatered recipe slurry. 7. A recipe of S273C with 10% slag wool was made. Slight improvement in forming. 8. System drained and fresh 3273 tried again. Still no improvement. Incomplete forming around sprue; insufficiently dewatered material delayers: when cool opens,one-ha If adhering to the cop cool and one-h:.If to the bottom cool. 9. Stopr test at 1:00 p.m. Manufacturing to return to P-31. 10. Same . .blem present after pumping over P-31. Finally drained entire system and used pure P-31. Still having same type of de layering and malforming around sprue. 11. Replaced defective vacuum hose at 3:30. Forming started to improve, however still not getting good formation around sprue. 12. Still crying to run P-31. By 6:30 p.m. began to fora good piece on right side cavity, not on left. By 8:00 p.m. began to fora good pieces and continued so through remainder of 2nd and 3rd shift. FQS--0--000000i455 1548 I.'on-Asbcscos Production Tcsc Tuesday, 5/8/73 May 9, 1973 Page 2 Individual Remarks: AS 1. Seeding of solids is unexplained by any laboratory evidence. Lab samples sac from Thursday co Tuesday vieh'no densificacion of suspended solids. JCM 1. Problems encountered not totally due to slupry since we had problems with P-31 when trying to start up. 2. Should not have made recipe changes so quickly during c.-.rly stage of test before equipment was proved out. WH 1. Slurry system responsible for forming difficulties. (a) Fines still passing through screen plugging tool. (b) Every non-asbestos run shows hours of down time trying to go back to P-31. (c) 7 hours of running P-31 unplugged the tooling. CHF 1. There must be a significant difference in the behaviour of these slurries in a K-4 delivery system versus a lab Ertel apparatus or Mark III machine. The violent aeration and agitation experi enced during form and blowback needs to be duplicated on a laboratory scale. I feel that this is necessary in order co reconcile our inability co transfer lab recipes to production equipment with any degree of reproducibility. Reconnended Action to be Taken: AS - EA 1. A'recipe of 5273B (15Z solids) replacing pearlite with diacomice & JCM should be tested at the next opportunity. RTC 2. K-4 upper and lower cools need to be removed and examined by RTC and steam cleaned if necessary before next experimental run. CHF:*lr:193 Distriby.ti.on: ._ P. A. Partington, 11. D. Shephard, E. Auzenbergs, W. C. Fleccher, G. Fenton, A. Sancighian/R. Dzurilla/D. Butler, R. B. Orndorff, R. T. Callahan, W. lloccvar, J. C. Mohr 1549 PQd-aa-1