Standard Flanges

New standards have larger than nominal size inside diameter to 12" size -
above 12" the ID is same as nominal
Old ANSI standards have same ID as the nominal size
For water: neoprene, red rubber, ½" to 36"; full-face and raised face (ring)
For fuels & oils: ½" to 24" full-face and raised face (ring)
nitrile (NBR, buna-n), Viton®, vegetable fiber
and compressed sheet: Gardico 522T, Klinger C-4401, Garlock 3200
For steam to 750o F: ½" to 36" full-face and raised face (ring)
compressed sheet, aramid fiber with nitrile binder
Gardico 522T, Klinger C-4401, Garlock 3200
For engine applications to 1200o F: synthetic fiber and nitrile with metal insert:
Gardico 596B.
For exhaust systems to 1800o F: vermiculite & ceramic fiber with metal insert
Gardico 596E, 596G