Marking EPDM Rubber

EPDM (Ethylene Propylene Diene Monomer) rubber has many uses where resistance to weathering, ultraviolet radiation, and heat are important factors. Commonly used for decades as a low-slope industrial roofing material, EPDM is also making substantial inroads in the automotive industry because its high heat resistance outperforms natural rubber in engine bay and chassis applications requiring durable boots and seals.

This application trial involved marking an easily readable identification code (with the potential to outlast the lifetime of the part) on an EPDM roofing gasket. Because the CO2 laser interaction with the EPDM provides an engraved mark with a metallic-like contrast, you can obtain similar marks on other EPDM rubber products where identification, tracking, or part numbers must appear on the part itself.

The marking set-up included a Synrad sealed CO2 laser, an FH Series marking head equipped with a 200-mm focusing lens, and a copy of the Synrad WinMark Pro laser marking software. The 200 mm lens provides a 290-micron (0.011”) spot with a 5 mm (0.196”) depth of focus. In WinMark Pro, a seven-character identification string was created using WinMark’s built in ‘Simple’ stroke font and set a Text Height of 7.6 mm (0.3”). On the Marking tab, a Power (duty cycle percentage) was set corresponding to 10 watts, set Velocity to 381 millimetres per second (15 inches/sec), and entered a Resolution value of 300. With these settings, the mark shown was obtained in a cycle time of 0.36 seconds per part.

This EPDM roofing gasket was marked using10 watts of power at a speed of 15 IPS in a cycle time of 0.36 seconds and exhibits a permanent, easily readable mark.

Laser Lines Ltd
Beaumont Close
Banbury
Oxon
OX16 1TH

Tel: +44 (0) 1295 672500
Fax: +44 (0) 1295 672550
Email: info@laserlines.co.uk
Website: www.laserlines.co.uk