Trelleborg Sealing Solutions launches Turcon® MC1 and Turcon® MC2 materials, the only polytetrafluoroethylene (PTFE) based electrically conductive materials suited for use in spring and elastomer-energized seals. Engineered for dynamic applications, seals and bearings from the materials will provide a reliable electric connection between moving parts.
Virgin PTFE is an excellent insulator with resistivity around 2×10+17 Ohm-cm. For PTFE composites to be able to conduct electricity, conductive fillers must be added, and these need to interconnect within the PTFE matrix. Historically, the only conductive PTFE-based materials were compounds with carbon filling above a “threshold value”.
The fact that electrical conductivity was achieved in these original carbon-filled PTFE-based materials was accidental and electrical resistance was not the primary engineering requirement. Turcon® MC1 and Turcon® MC2 differ though, in that they have been specifically developed for electrical conductivity in dynamic sealing applications and therefore sealing performance is optimized in these situations.
To prove the electrical conductivity of Turcon® MC1 and Turcon® MC2, the compounds underwent significant testing in the Trelleborg’s in-house labs, including in a specialized test rig that simulated real-life conditions. Results showed that Turcon® MC1 and Turcon® MC2 had a dry contact resistance that was negligible (highly conductive) even with low contact pressure and when running in oil, resistance was also low and thereby, conductivity was high.
Turcon® MC1 is a medium-filled material for dynamic applications requiring medium to high conductivity, while Turcon® MC2 is a high-filled material for dynamic applications requiring high conductivity.