Hella KG Hueck & Co, which makes headlights for General Motors Europe’s Astra line, has replaced the original EPDM thermoset rubber seal used in the light units with Santoprene thermoplastic vulcanisate (TPV) supplied by Advanced Elastomer Systems (AES).

The application was developed by Beckenbach GmbH, which builds injection moulds and manufactures thermoplastic elastomer and thermoset rubber products, systems and parts.

AES claims the Santoprene TPV 121-50 M100 grade chosen offers stable dimensional tolerances over the vehicle’s lifetime while excellent sealing properties are achieved thanks to good stress relaxation and compression set characteristics.

Benefits from the change include reduced part cost and while moulding tolerance control, essential for consistent production, was maintained without any flash – a task not possible with thermoset rubber.

AES further claims that Santoprene TPV 121-50 M100 provides significant benefits compared to EPDM thermoset rubber, such as excellent heat ageing/low temperature flexibility, easy injection moulding in thin wall sections, lower part processing cost, fast cycles/less labour (with no part post-treatment), greater design potential for complex-shaped parts and is 100% recyclable.