Gaskets are crucial components in flanged connections, providing a seal between the mating flange faces to prevent leakage of fluids or gases. There are several types of gaskets available, each designed for specific applications and operating conditions. Here are some common types of gaskets for flanges and their uses:
1. Non-Metallic Gaskets:
- Compressed Non-Asbestos (CNA) Gaskets: Made from synthetic fibers and fillers bonded with elastomers. They are suitable for general-purpose applications where moderate temperature and pressure conditions are present.
- Rubber Gaskets (Neoprene, EPDM, Nitrile): These gaskets are made from various types of rubber materials and are suitable for applications requiring resistance to water, weathering, and some chemicals. They are commonly used in low-pressure and low-temperature applications.
- PTFE (Polytetrafluoroethylene) Gaskets: Known for their excellent chemical resistance and low friction properties. PTFE gaskets are suitable for high-temperature and corrosive applications, such as in the chemical and pharmaceutical industries.
2. Metallic Gaskets:
- Spiral Wound Gaskets: Constructed with alternating layers of metal winding strip and filler material (usually graphite or PTFE). Spiral wound gaskets are suitable for high-pressure and high-temperature applications, providing excellent resilience and sealing performance.
- Ring Joint Gaskets: Designed to seal flanged connections in high-pressure and high-temperature applications, such as oil and gas pipelines. They are made from metal materials (e.g., soft iron, stainless steel) and feature a unique ring shape with a trapezoidal cross-section.
3. Composite Gaskets:
- Kammprofile Gaskets: Constructed with a metallic core and facing material (e.g., graphite, PTFE) on both sides. Kammprofile gaskets combine the strength of metal with the resilience of non-metallic materials, making them suitable for a wide range of temperature and pressure conditions.
- Corrugated Metal Gaskets: Made from thin metal sheets with corrugated or serrated profiles. Corrugated metal gaskets are suitable for high-pressure and high-temperature applications, providing excellent sealing performance and resistance to flange rotation.
4. Expanded PTFE Gaskets:
- Made from expanded PTFE material, these gaskets offer excellent chemical resistance and conformability. They are suitable for sealing irregular or damaged flange surfaces and are commonly used in chemical processing and pharmaceutical applications.
5. Retrofit Gaskets:
- Designed to retrofit existing flanged connections without the need for machining or modifying the flange faces. Retrofit gaskets are available in various materials and configurations to suit different application requirements.
These are just a few examples of the types of gaskets available for flanged connections. The selection of the appropriate gasket type depends on factors such as operating conditions, temperature, pressure, fluid compatibility, and flange face finish. It's essential to choose the right gasket for your specific application to ensure a reliable and leak-free seal.
