Flat Face Flange

Full plane design: The sealing surface is completely flush with the flange end face, and sealing is achieved by tightening the gasket with bolts. It is suitable for low or medium pressure systems (such as PN6-PN300).
Compatibility: Usually used in conjunction with flat gaskets (such as rubber, asbestos, or metal wrap gaskets), ensure that the flanges are parallel and aligned during installation to avoid leakage.
Simplified maintenance: No complex geometric structure, easy disassembly and replacement of gaskets.

Common materials:
Carbon steel: ASTM A105/A105N (room temperature), A350 LF2 (low temperature use conditions).
Stainless steel: ASTM A182 F304/F316L (corrosion resistant).
Manufacturing standards:
American standard: ANSI B16.5 (pressure rating: 150 pounds to 2500 pounds).
International standards: DIN, JIS, EN1092-1, etc. enable projects to be adapted globally.
Surface treatment: electroplating, hot-dip galvanizing or anti rust coating (such as yellow paint, black paint) to enhance corrosion resistance.

Low pressure fluid systems, such as water supply and drainage, HVAC, etc., require low sealing pressure and are cost-effective.
Chemical and food industries: Stainless steel flat flanges are used for sanitary pipes (polished surface Ra≤0.8 microns), in line with FDA or EHEDG certification requirements.
Modular equipment: Due to its simple structure, it is often used for modular or quick installation of prefabricated pipes.

Advantages of Flat Face Flange:
Low cost: The processing difficulty is lower than that of convex or ring connecting flanges, making it suitable for large-scale production.
Wide adaptability: compatible with multiple gasket types, high flexibility.
limitations:
High pressure limit: Not suitable for ultra-high pressure systems (2500 and above), because flat contact is prone to leakage due to uneven pressure.
High installation accuracy requirements: The parallelism of the flange must be strictly maintained, otherwise it may cause damage to the seal.