Harold_V wrote: ↑Sun Dec 19, 2021 4:48 pm
What Jim said. And it need not have water on it when it is introduced to the molten mass in the crucible. Cold metal introduced to the discharge from a furnace will quickly condense moisture on its surface, causing a steam explosion when it is submerged (don't ask how I know).
It is good policy to prewarm metal above the dew point before introducing it to a crucible that contains molten metal.
H
Harold is right.
I have seen the aftermath of a "pop," as they call it in the industry. Only, this pop had two pops... The first was a outward vertical pop, there was still metal on the roof of the building a few years later when it shut down. The second pop broke the pot in the furnace and blew out the "weep hole" that is used to detect if there is a cracked pot, with enough force to produce a 3/4" thick slab of aluminum about 8' wide, 20' long. Thankfully there were no team members walking by at that time - that could very well have been fatal for that team member. I won't go into the root cause, but let's just say that warming up your tools prior to handling molten aluminum is a critical factor in safe aluminum foundry practice. As a foundry engineer, I am often up on the pour deck watching team members and their pouring techniques as well as looking for any opportunities for improvement. I had just vacated my usual observing spot about ten minutes before the incident - a blessing at the time. I also keep my head on a swivel - if I see a new tool brought onto the pour deck that I do not know has been properly prepared for use (coated, dried, pre-warmed to dry out any moisture), I take about forty steps back to protect myself.
Thankfully the team member was not injured save for a few minor splatters of aluminum. Pretty sure his life flashed before his eyes, though.