A class 150 flange can be created from various materials like stainless steel, carbon steel, ductile iron, cast iron, etc and is resistant to abrasion & corrosion with high durability. Flanges such as American standard flanges, British standard flanges and German standard flanges created using above mentioned materials have separate pressure ratings.

The pressure rating of flanges depends on various factors which we will look at in the following section.

Flanges are able to resist different pressure values at different & varied temperatures. With increase in temperature pressure rating of a flange decreases. Let us take an example to illustrate what happens; Class 150 flanges rates to about 270 PSIG (in ambient conditions), at 400 F a PSIG of 180, at 600 F a PSIG of 150 & 75 PSIG at 800 F. So it all depends on the fluid’s operating temperature.