M9213 - Manufacture of rock wool insulation

Operational Details
Fiberglass insulation manufacturing includes the use of sand, fluorspar, barytes, limestone, and soda ash. They are mixed in a batching silo, carried by conveyors and layered in a furnace, where exposed electrodes convert the mixture to a molten glass. The glass is drawn from the smelter, to spinning chambers which contain microscopic holes. The glass is cooled and spun into fibers. As the fibers are formed, they are sprayed with a binder and blown down onto a conveyor system where the fibers form a cotton candy-like mass.

As the fibers accumulate on the conveyor they form a blanket. The thickness of the glass is controlled by the speed of the conveyor. The blanket is conveyed through an oven where it is compressed and cured. After cooling, the fiber blanket is cut to width and length, seared, marked, and packaged through a heat sealing process

SIC Codes
000000604 - Manufacture of rock wool insulation