Flange gaskets are essential components used to create a seal between two flange faces in piping systems. Flanges are flat, circular discs with bolt holes around the perimeter, and they are used to connect pipes, valves, and other equipment in various industries such as oil and gas, chemical processing, water treatment, and HVAC (Heating, Ventilation, and Air Conditioning). Flange gaskets are placed between the flange faces to prevent leakage of fluids or gases from the joint. Here are some key features and types of flange gaskets:

1. Material: Flange gaskets are made from a variety of materials, each offering different properties suited to specific applications and operating conditions. Common materials include:

   • Soft Cut Gaskets: Made from non-metallic materials such as rubber (e.g., EPDM, neoprene), compressed fiber (e.g., non-asbestos, PTFE), or flexible graphite. These materials provide flexibility, resilience, and chemical resistance.
   • Metal Gaskets: Made from metal materials such as stainless steel, carbon steel, or alloy metals. Metal gaskets provide high temperature and pressure resistance, as well as resistance to corrosion and deformation.

2. Type of Seal:

   • Full-Face Gaskets: Full-face gaskets cover the entire face of the flange, including the bolt holes. They are suitable for flat-faced flanges and provide a complete seal across the entire surface area of the flange joint.
   • Ring-Type Gaskets: Ring-type gaskets are designed to fit inside the bolt circle of raised face or flat-faced flanges. They are available in various designs, including spiral wound, octagonal, and oval, and they provide a seal only at the contact points between the flange faces.

3. Profile: Flange gaskets may have different profiles or shapes to match the geometry of the flange faces. Common profiles include:

   • Flat: Flat gaskets are used with flat-faced flanges and provide a simple, economical sealing solution.
   • Raised Face: Raised face gaskets have a raised surface around the bolt holes to match the raised portion of raised face flanges. This design helps concentrate the sealing force on the contact points between the flange faces.
   • Tongue and Groove: Tongue and groove gaskets feature interlocking profiles that provide additional stability and resistance to lateral movement in flange joints.

4. Temperature and Pressure Ratings: Flange gaskets are available in different materials and designs to accommodate a wide range of temperature and pressure requirements. It’s essential to select gaskets that are compatible with the specific operating conditions of the application.

5. Installation: Proper installation of flange gaskets is crucial for achieving a tight and reliable seal. Gaskets should be clean, free from damage, and positioned correctly between the flange faces before tightening the bolts to the specified torque.

Flange gaskets play a critical role in maintaining the integrity and reliability of piping systems by preventing leakage at flange joints. Proper selection, installation, and maintenance of flange gaskets are essential for ensuring leak-free operation and minimizing downtime in industrial processes.