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View Full Version : Ramp Profile for new crucible.


Dave Hilty
01-09-2012, 03:53 PM
Pete,

Assuming I've replaced the crucible & crown (doing this evening) in the baby Moly I've got here, what is the appropriate ramping program? I've always thought that the key is to go slow (24 D.per hour max) between 950 and 1200 D.F. Is it just fine to go for broke to reach the initial 950 F.?, then a soak to let stuff even out (8=10 hours) basically overnight and then 25 per hour to 1200 and then go for broke to charging temps again. I know this wouldn't be appropriate for a new un-fired furnace but that's not the case here. You've explained quartz inversion before but I've forgotten what range that is confined to.

Pete VanderLaan
01-09-2012, 04:15 PM
the quartz range starts at about 930F and runs up to 1100F. I think if you go look at the ramp I mentioned in "Another cautionary tale" that I put up this morning, you will get a good idea of what I do with a half full pot that's gone cold. You could pretty much cut the program times in half, or double them depending on how you look at it. keep your ramp constant. jamming up to 930F is not a good idea.