What are the flange materials of bendable rubber expansion joints?

Flexible rubber expansion joint flanges are generally divided into carbon steel flange, forged flange and stainless steel flange these three.
Carbon steel flange in the use and production with different hardness and strength, different materials of carbon steel flange can probably be used in the use of different advantages and characteristics, low carbon steel plasticity good strength low. In general, carbon steel flanges more than the use of spraying anti-corrosion treatment, so that the casting process generated by the pores covered by plastic powder, it will make up for the shortcomings of carbon steel flanges, the appearance of almost invisible pore phenomenon
Stainless steel itself has very good performance. Stainless steel in use can effectively resist corrosion, pitting, rusting, and stainless steel is very rigid, difficult to wear. Also because of its unique advantages, no need to do any treatment, can be used directly, and more widely used in anti-corrosion pipeline, service life. Because of the very good corrosion resistance, the engineering integrity of the structural parts can be permanently maintained.
Forged flange is invented on the basis of cast steel flange, its strength is much higher than the cast steel flange. Forged flange with holes, bolts to make two flange tightly connected. Forged flange with a gasket seal between. Forged flange fittings refer to the fittings with forged flange.
Forging flange sealing surface type has three kinds: flat type sealing surface, suitable for the pressure is not high, the media non-toxic occasions; concave and convex sealing surface, suitable for slightly higher pressure occasions; tongue and groove sealing surface, suitable for flammable, explosive, toxic media and higher pressure occasions.