II. Structural Types and Functions
| Gasket Type | Characteristics and Applications |
|---|
| Pure PTFE Gasket | Machined from sheet materials; basic sealing component for low-pressure static seals. |
| Expanded PTFE Gasket | Microporous structure enhances compression resilience; adapts to irregular flange surfaces. |
| Filled Modified Gasket | Reinforced with fiberglass/graphite to improve creep resistance (PV value increased by 3–5×). |
| PTFE-Enveloped Gasket | PTFE outer layer with non-metallic core (e.g., asbestos-free board); corrosion-resistant at high pressure. |
| O-Ring Flange Gasket | Ring-shaped seal for dynamic applications (e.g., pump/valve rotating shafts). |
Note: Expanded PTFE (ePTFE) forms microfiber structures via stretching, achieving sealing pressures up to 10.5 MPa.
IV. Key Performance Parameters
| Parameter | Standard Value |
|---|
| Maximum Operating Pressure | ≤45 MPa (up to 60 MPa for modified types) |
| Sealing Leakage Rate | <1×10⁻⁹ Pa·m³/s |
| Creep Resistance | Deformation <5% under long-term load |
| Applicable Flange Standards | ASME B16.21, DIN 2690 |
