Gaskets are classified based on material, construction, and application:

A. Non-Metallic Gaskets

• Rubber Gaskets (EPDM, Nitrile, Neoprene, Silicone): Used in low-pressure, low-temperature applications (e.g., water, air, chemicals).
• Cork Gaskets: Used in fuel systems and automotive applications for vibration damping.
• PTFE (Teflon) Gaskets: Resistant to chemicals and high temperatures; common in chemical processing.
• Compressed Fiber (Non-Asbestos) Gaskets: Made from aramid, cellulose, or glass fibers; used in pipelines, engines, and industrial flanges.

B. Semi-Metallic Gaskets

• Spiral Wound Gaskets: Alternating layers of metal (stainless steel, carbon steel) and filler (PTFE, graphite). Used in high-pressure/temperature applications.
• Camprofile Gaskets: Metal core with a serrated face and soft sealing layer. Ideal for uneven flange surfaces.
• Metal Jacketed Gaskets: Soft filler enclosed in a metal jacket. Used in heat exchangers and high-pressure steam systems.

C. Metallic Gaskets

• Ring-Type Joint (RTJ) Gaskets: Made of soft iron, stainless steel; used in high-pressure oil/gas pipelines.
• Flat Metal Gaskets: Simple designs for high-temperature applications.
• Corrugated Metal Gaskets: Used in heat exchangers and exhaust systems.

Gaskets are produced according to international standards to ensure compatibility and performance:

• ASME (American Society of Mechanical Engineers): B16.20 (Spiral wound/Ring-joint); B16.21 (Non-metallic flat).
• ASTM (American Society for Testing and Materials): ASTM F104 (Materials); ASTM F37 (Testing).
• EN (European Norms): EN 1514 (Dimensions); EN 12560 (Flange gaskets).
• API (American Petroleum Institute): API 6A (Wellhead equipment).
• DIN (Deutsches Institut für Normung): DIN 2690 (Flange gaskets).

• Oil & Gas: Pipeline flanges, valves, pumps (RTJ, spiral wound).
• Chemical Processing: PTFE gaskets for corrosive fluids.
• Power Plants: High-temperature graphite gaskets for steam systems.
• Automotive: Cork/rubber gaskets for engines and fuel systems.
• Pharmaceutical/Food: FDA-approved silicone/PTFE gaskets.
• HVAC: Rubber/fiber gaskets for air/water sealing.

Gasket selection depends on factors like temperature, pressure, fluid compatibility, and flange type. Standards ensure reliability, while material choice determines performance in specific environments.

Stud bolts and nuts are essential fasteners used to assemble flanged joints, pressure vessels, and piping systems, providing strong clamping force for leak-proof connections.

1. Types of Stud Bolts

• Fully Threaded Stud Bolts: Threads run entire length; common in general flange connections.
• Double-End Stud Bolts: Threads on both ends with a shank; used in high-vibration applications.
• Continuous Threaded Stud Bolts: Uniform diameter; used in structural applications.

2. Types of Nuts

• Hex Nuts (Heavy Hex): Most common, used in high-pressure applications.
• Flange Nuts: Built-in washer to distribute load.
• Lock Nuts: Prevent loosening due to vibration.
• Castle Nuts: Used with cotter pins for secure fastening.

3. Material Selection