Debate time: proper preheat for gray iron in a 2-ton furnace

I mean, I keep seeing guys at our shop in Toledo rush the preheat to 1250F and pour, but our old foreman always held it at 1400F for a full hour. The rushed batches keep having chill issues in the thin sections, idk maybe it's just me but that extra time matters. Which way gets you a more consistent casting without wasting fuel?

2 comments

2 Comments

hernandez.ben4d ago

Our old schedule of 1400F for an hour always fixed those thin section problems.

alice_reed474d ago

Ever think about what the mold is doing while you wait? That gray iron at 1250F hits a cold sand mold and the heat shock can actually change the sand's surface right where you need a clean pull. Holding at 1400F lets the whole system, iron and mold, settle into a closer temp range. It's not just about the metal soup, it's about the first inch of sand not acting like a heat sink. Rushing it asks for veining or cuts along with the chill.