Trelleborg seals advance for high-speed EV motors

Trelleborg, Sweden - Trelleborg Sealing Solutions (TSS) has introduced a new FKM elastomer-based radial shaft-seal designed for high-speed electric vehicle (EV) motors.

The Stefa HiSpin EV40 is claimed to set a new standard in providing “superior low-friction sealing while offering exceptional performance and durability for EV applications.”

Engineered to perform at shaft speeds over 20,000 rpm, the seal features Trelleborg’s patented 'phase-shifted-wave' hydrodynamic technology, TSS said 15 April.

The technology, it stated, actively pumps fluid back to the oil side during shaft rotation to maintain sealing efficiency in highly lubricated environments.

The patented hydrodynamic feature consists of multiple grooves with single-sided 'waviness', separated by static bands, said Nino Dakov, manager technology engineering at TSS.

“The shifted waviness between neighbouring grooves enables gradual back-pumping from the air to the oil side,” Dakov explained.

The design, according to the TSS expert, was developed through finite element analysis and optimising the seal assembly across different sizes.

The seal was tested under high-speed conditions of up to 20,130 rpm for 240 hours without leakage or wear, the Trelleborg release continued.

The component, it reported, withstood “extreme speeds and temperatures” in a separate 1,000-hour test for durability without compromising integrity.

Furthermore, the seal is made with “specially formulated” FKM material, which according to TSS is compatible with various electric axle fluids.