Document a4kqn9JKv95Y3LmGqGxDerXzB

E. J. Jago / ; / P. A. Partington May 16, 1972 ASBESTOS FREE PROFAX / W.C.FLETCHER MEMO TO YOU HAY 5 I 1099 m confidential MELTING TRIALS OF HOT TOP MATERIAL ON LABORATORY SCALE Reason for trials: We have fount! out that the new type of Vallak tiles have given some problems to the ingots after stripping because the tiles melt and stick to the ingot surface. Therefore, we have made some trials to compare the Vallak and the E Box to find out the standing for high temperatures. Results: Enclosure HI shows photographs of Vallak tiles from Fagcrsta och Ilagfors and also E Box's samples: (1) with asbestos, and (2) with mineral or slag wool replacing the asbestos. The samples have been heated up to 1300 C, 1400C, and 1500C in an oven for a 10-minute period. We found that the Vallak material starts to sinter already at 1300C and begins to melt at 1400 C. At 1500 C, the Vallak tile was completely melted out. Concerning the E Box, sintering started first at 1500C. The material however seems to be more porous than v'.iat the Vallak tile did at 1300C. At 1300 C, we could easily crush down the E Box material. No tendency cf sintering could be found. No remarkable difference between the two Vallak tiles could be found. There was no difference between E Box samples with asbestos and E Box with mineral wool (asbestos-free). Vie nave found the sintering temperature of E Box to be 200 C above that of the Vallak tiles. Furthermore, the Vallak tiles start to melt 100 C. before the E Box starts to melt. E-Rox present recipe (all products) Olivine sandMineral wool I*h. resin UF Newsprint B8X 3.2 1.6 1.3 5.9 Ingot tests show no difference in yield between asbestos and asbestos-free. n 1100