Generator rotor housing sand casting

4–5-inch-thick cast-iron generator housings the size of a small house — the size-extreme example for sand casting. ## Figures referenced (recurring numeric anchors, not cases) - Steel mill yield improvement: 65% → 90% → 97% with continuous casting (`§7.p3`). - $6,000 single-crystal turbine blade unit cost (`§4.p6`, `§4.p9`). - 100 ounces/year world iridium production (`§5.p6`, `§7.p18`). - ~50 years of unsuccessful continuous-cast steel-strip research (`§7.p18`). - 75% area reduction as minimum for breaking down macrosegregation in heavy forgings; 90% preferred (`§8.p16`–`§8.p19`). - $6M wire contract, $300M overall project, $2M savings claim — trolley wire forensic case (`§9.p6`–`§9.p11`).

You also can make big cast-iron parts the size of this room. If I have a generator rotor forging — we talked about generator rotor forgings yesterday — I have to have a housing to put it in. Once I take that steel rotor and wind it with copper, I need a housing to hold the other windings to make my big generator. That generator housing is about four or five inches thick cast iron, the size of a small house. There's a top and a bottom, and it's a big sand casting — just bigger than the little nipples you buy at the hardware store.