Flanges can either be forged or cast. Both manufacturing methods have their advantages and disadvantages, depending on the application you have in mind for your flange. Here at Texas Flange, we primarily deal with forged flanges due to the outdated nature and lower standard of quality of cast flanges. Below, we will delve into the advantages and disadvantages of both forged steel flanges and cast iron flanges. http://www.gcflange.com/plate-flanges/