The 15% graphite PTFE rod for seal applications is engineered to bridge the gap between standard PTFE and high-performance filled polymers. This grade uses a controlled 15% graphite dispersion to improve thermal conductivity, reduce wear, and lower dynamic friction in rotary and reciprocating seal systems. It starts from the same high-density process used for our graphite filled PTFE round bar range, but with tighter dimensional control for seal machining. In dry-running pumps and mixers, it functions as an effective low friction graphite PTFE rod by developing a self-lubricating transfer film on mating metal surfaces. As a dedicated 15% graphite PTFE rod manufacturer, we certify graphite content, density, and tensile properties on every production lot. The material also serves as a direct PTFE rod with graphite lubrication replacement for unlubricated PTFE seal components that are prone to scoring, heat checking, or early leakage. Typical seal applications include valve stem packings, agitator seals, hydraulic cylinder rings, and rotary shaft lip seals.
| Property | Test Method | Typical Value |
|---|---|---|
| Graphite content | Internal QC | 15% ± 1% |
| Density | ASTM D792 | 2.10–2.15 g/cm³ |
| Tensile strength | ASTM D4894 | 14–18 MPa |
| Elongation at break | ASTM D4894 | 150–220% |
| Hardness | ASTM D2240 | 60–65 Shore D |
| Compressive strength at 1% strain | ASTM D695 | 6–8 MPa |
| Dynamic coefficient of friction | ASTM D1894 | 0.05–0.10 |
| Thermal conductivity | ASTM E1461 | 0.45–0.60 W/m·K |
| Continuous service temperature | — | -200°C to +260°C |
| Creep resistance | ASTM D621 | Improved vs. virgin PTFE |
| Static seal pressure limit | — | up to 25 MPa |
When machining the 15% Graphite PTFE Rod into seal components, the graphite filler provides several measurable benefits. It reduces the coefficient of friction under boundary lubrication, improves load-bearing capacity by resisting creep, and dissipates frictional heat before it can soften the PTFE matrix. The rod is supplied in stress-relieved condition to minimize ovality and internal stress after machining. For seal rings, pre-machining the rod to a rough oversize and then annealing at 120°C to 150°C for 2–3 hours helps stabilize dimensions before final cutting. The rod is compatible with most acids, alkalis, solvents, and oxidizing media, making it suitable for chemical processing, food-grade equipment, and pharmaceutical sealing. Because graphite is electrically conductive, avoid specifying this grade in applications where high dielectric strength is required. It performs best in contact with hardened stainless steel, ceramic-coated shafts, or chrome-plated rods. For high-cycle pneumatic and hydraulic sealing, pairing the rod with proper gland design and avoiding sharp corners will extend service life.
