Technical Data Sheet
PTFE Butterfly Valve Seat
Specialized Items
Polytetra Processors
Rakhial, Ahmedabad, Gujarat, India
www.automatasia.com
Butterfly valve seats manufactured to standard sizes from 2" N.B. to 12" N.B. with accurate sealing geometry.
Specification
| Sizes | 2–12 in nominal bore |
|---|---|
| Tolerances | Sealing geometry to valve sample or approved drawing; CNC work available to ±0.05 mm where applicable |
| Grades | Virgin PTFE, 15% Glass-filled PTFE, 25% Glass-filled PTFE, 25% Carbon-filled PTFE, Bronze-filled PTFE |
| Standards | ASTM D4894, ASTM D4745 |
| Typical uses | Butterfly valve sealing, Valve refurbishment |
| Industries | Chemical, Water treatment, Process plants |
Typical properties — virgin PTFE
| Property | Typical value | Test method |
|---|---|---|
| Specific gravity | 2.14 – 2.20 | ASTM D792 |
| Tensile strength | 20 – 35 MPa | ASTM D638 / D4894 |
| Elongation at break | 200 – 400 % | ASTM D638 / D4894 |
| Hardness | Shore D 50 – 65 | ASTM D2240 |
| Coefficient of friction (dynamic) | 0.04 – 0.10 | ASTM D1894 |
| Continuous service temperature | −200 °C to +260 °C | — |
| Melting point | ≈ 327 °C | ASTM D4894 |
| Dielectric strength | ≈ 32 kV/mm (short time, thin section) | ASTM D149 |
| Water absorption | < 0.01 % | ASTM D570 |
Typical values for guidance only, not guaranteed minimums. Filled grades, linings and finished parts differ; confirm limits for your application. Issued 2026.